Agilent E4416A Programming Guide

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Errata

This manual may contain references to HP or Hewlett-Packard. Please note that Hewlett-Packard's former test and measurement, semiconductor products and chemical analysis businesses are now part of Agilent Technologies. To reduce potential confusion, the only change to product numbers and names has been in the company name prefix: where a product number/name was HP XXXX the current name/number is now Agilent XXXX. For example, model number HP8648 is now model number Agilent 8648.

Ce manuel peut contenir des références à <<HP>> ou <<Hewlett-Packard.>> Veuillez noter que les produits de test et mesure, de semi-conducteur et d'analyse chimique qui avaient fait partie de la société Hewlett-Packard sont maintenent une partie de la société Agilent Technologies. Pour reduire la confusion potentielle, le seul changement aux noms de reference a été dans le préfixe de nom de société : là où un nom de référence était HP XXXX, le nouveau nom de référence est maintenant Agilent XXXX. Par example, le HP 8648 s'appelle maintenent Agilent 8648.

Diese Gebrauchsanweiseung kann Bezug nehmen auf die Namen HP oder Hewlett-Packard. Bitte beachten Sie, dass ehemalige Betriebsbereiche von Hewlett-Packard wie HP-Halbleiterprodukte, HP-chemische Analysen oder HP-Test- und Messwesen nun zu der Firma Agilent Technology gehören. Um Verwirrung zu vermeiden wurde lediglich bei Produktname und - Nummer der vo laufende Firmenname geändert: Produkte mit dem Namen/Nummer HP XXXX lauten nun mehr Agilent XXXX. Z.B, das Modell HP 8648 heißt nun Agilent 8648.

Questo manuale potrebbe contenere riferimenti ad HP o Hewlett-Packard. Si noti che le attività precedentemente gestite da Hewlett-Packard nel campo di Test & Misura, Semiconduttori, ed Analisi Chimica sono ora diventate parte di Agilent Technologies. Al fine di ridurre il rischio di confusione, l'unica modifica effettuata sui numeri di prodotto e sui nomi ha riguardato il prefisso con il nome dell'azienda : dove precedentemente compariva "HP XXXX" compare ora "Agilent XXXX". Ad esempio: il modello HP8648 è ora indicato come Agilent 8648.

Este manual puede hacer referencias a HP o Hewlett Packard. Las organizaciones de Prueba y Medición (Test and Measurement), Semiconductores (Semiconductor Products) y Análisis Químico (Chemical Analysis) que pertenecían a Hewlett Packard, ahora forman parte de Agilent Technologies. Para reducir una potencial confusión, el único cambio en el número de producto y nombre, es el prefijo de la compañía: Si el producto solía ser HP XXXX, ahora pasa a ser Agilent XXXX. Por ejemplo, el modelo HP8648 es ahora Agilent 8648.

Document Part Number 5971-2668 Printed in the UK September 2004

A

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マニュアル・チェンジ

変更

本文中の「HP（YHP）」、または「(横河)ヒューレット・パッカード株式会社」とい

う語句を、「Agilent」、または「アジレント・テクノロジー株式会社」と変更して

ください。

ヒューレット・パッカード社の電子計測、半導体製品、化学分析ビジネス部門は分

離独立し、アジレント・テクノロジー社となりました。

社名変更に伴うお客様の混乱を避けるため、製品番号の接頭部のみ変更しておりま

す。

（例: 旧製品名 HP 4294A は、現在 Agilent 4294A として販売いたしておりま

す。）

Page 3

Programming Guide

Agilent Technologies

EPM-P Series Power Meters

Agilent Technologies Part no. E4416-90029

June 2001

Page 4

written permission is prohibited, except as allowed under the copyright laws.

Printed in t he UK.

ii EPM-P Series Power Meters Programming Guide

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Equipment Operation

Warnings and Cautions

This guide uses warnings and cautions to denote hazards.

WARNING A warning calls attention to a procedure, practice or the

like, which, if not correctly performed or adhered to, could result in injury or the loss of life. Do not proceed beyond a warning until the indicated conditions are fully understood and met.

Caution A caution calls attention to a procedure, practice or the like which,

if not correctly performed or adhered to, could result in damage to or the destruction of part or all of the equipment. Do not proceed beyond a caution until the indicated conditions are fully understood and met.

Personal Safety Considerations

WARNING This is a Safety Class I pro duct (provided with a protecti ve

earthing ground incorporated in the power cord). The mains plug shall only be inserted in a socket outlet provided with a protective earth contact. Any interruption of the protective conductor, inside or outside the instrument, is likely to make the instrument dangerous. Intentional interruption is prohibited. If this instrument is not used as specified, the protection provided by the equipment could be impaired. This instrument must be used in a normal condition (in which all means of protection are intact) only. No operator serviceable parts inside. Refer servicing to qualified personnel. To prevent electrical shock, do not remove covers. For continued protection against fire hazard, replace the line fuse (s ) o n l y w ith fuses o f th e same type a n d r ating (for example, normal blow, time delay, etc.). The use of other fuses or material is prohibited.

EPM-P Series Power Meters Programming Guide iii

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General Safety Considerations

WARNING Before this instrument is switched on, make sure it has

been properly grounded through the protective conductor of the ac power cable to a socket outlet provided with protective earth contact. Any interruption of the protective (grounding) conductor, inside or outside the instrument, or disconnection of the protective earth terminal can result in personal injury.

Caution Any adjustments or service procedures that require operation of

the instrument with protective covers removed should be performed only by trained service personnel.

User Environment

The product is suitable for indoor use only.

iv EPM-P Series Power Meters Programming Guide

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About this Guide

Chapter 1: Power Meter Remote Operation

This chapter describes the parameters which configure the power meter and helps you determine settings to optimize performance.

Chapter 2: MEASurement Instructions

This chapter explains how to use the MEASure group of instructions to acquire data using a set of high level instructions.

Chapter 3: CALCulate Subsystem

This chapter explains how to use the CALCulate subsystem to perform post acquisition data processing.

Chapter 4: CALibration Subsystem

This chapter explains how to use the CALibration command subsystem to zero and calibrate the power meter.

Chapter 5: DISPlay Subsystem

This chapter explains how the DISPlay subsystem is used to control the

the selection and presentation of the windows used on the power meter’s display.

Chapter 6: FORMat Subsystem

This chapter explains how the FORMat subsystem is used to set a data format for transferring numeric information.

Chapter 7: MEMory Subsystem

This chapter explains how the MEMory command subsystem is used to create, edit and review sensor calibration tables.

Chapter 8: OUTput Subsystem

This chapter explains how the OUTput command subsystem is used to switch the POWER REF output on and off.

EPM-P Series Power Meters Programming Guide v

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About this Guide

Chapter 9: SENSe Subsystem

This chapter explains how the SENSe command subsystem directly affects device specific settings used to make measurements.

Chapter 10: ST ATus Subsystem

This chapter explains how the STATus command subsystem enables you

to examine the status of the power meter by monitoring the “Device Status Register”, “Operation Status Register” and the “Questionable Status Register”.

Chapter 11: SYSTem Subsystem

This chapter explains how to use the SYSTem command subsystem to return error numbers and messages from the power meter, preset the power meter, set the GPIB address, set the command language and query the SCPI version.

Chapter 12: TRACe Subsystem

This chapter explains how to use the TRACe command subsystem to configure and read back the measured power trace.

Chapter 13: TRIGger Subsystem

This chapter explains how the TRIGger command subsystem is used synchronize device actions with events.

Chapter 14: UNIT Subsystem

This chapter explains how to use the UNIT command subsystem to se t the power meter measurement units to Watts and % (linear), or dBm and dB (logarithmic).

Chapter 15: SERVice Subsystem

This chapter explains how to use the SERVice command subsystem to obtain and set information useful for servicing the power meter.

Chapter 16: IEEE488.2 Command Reference

This chapter contains information about the IEEE488.2 Common Commands that the power meter supports.

vi EPM-P Series Power Meters Programming Guide

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About this Guide

Appendix A

This appendix contains information about the calibration factor block layout.

EPM-P Series Power Meters Programming Guide vii

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Related Publications

The EPM-P Series Power Meters User’ s Guide is available on the CD-ROM and in the following languages:

• English Language User’s Guide - Standard

• German Language User’s Guide - Option ABD

• Spanish Language User’s Guide - Option ABE

• French Language User’ s Guide - Option ABF

• Italian Language User’s Guide - Option ABZ

• Japanese Language User’s Guide - Option ABJ

Useful information on SCPI (Standard Commands for Programmable Instruments) can be found in:

• A Beginner’s Guide to SCPI, which is available by ordering

Agilent Part Number 5010-7166.

• The SCPI reference manuals which are available from: SCPI Consortium, 8380 Hercules Drive, Suite P3, La Mesa, CA 91942, USA. Telephone: 619-697-4301 Fax: 619-697-5955

viii EPM-P Series Power Meters Programming Guide

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Table of Conten ts

Page

Equipment Operation..................................................................iii

Personal Safety Considerations............................................iii

General Safety Considerations.................................................... iv

User Environment................................................................. iv

About this Guide ........................................................................... v

Related Publications..................................................................viii

Power Meter Remote Operation...................................................... 1-1

Introduction................................................................................... 1-2

Configuring the Remote Interface................................................ 1-3

Interface election .................................................................... 1-3

GPIB Address ......................................................................... 1-3

RS232/RS422 Configuration .................................................. 1-4

Zeroing and Calibrating the Power Meter .................................. 1-5

Zeroing .................................................................................... 1-5

Calibration.............................................................................. 1-5

Setting the Reference Calibration Factor ............................ 1-7

Making Measurements ................................................................ 1-8

Using MEASure? ................................................................... 1-9

Using the CONFigure Command ......................................... 1-14

Using the Lower Level Commands........................................ 1-23

Making Measurements on Wireless Communication Standards 1-24

Measuring GSM...................................................................... 1-24

Measuring EDGE .................................................................. 1-26

Measuring NADC .................................................................. 1-28

Measuring iDEN .................................................................... 1-31

Measuring Bluetooth.............................................................. 1-33

Measuring cdmaOne .............................................................. 1-35

Measuring W-CDMA.............................................................. 1-37

Measuring cdma2000 ............................................................ 1-39

Using Sensor Calibration Tables ................................................ 1-41

Overview ................................................................................. 1-41

Editing Sensor Calibration Tables ....................................... 1-44

................................................................................................. 1-48

Selecting a Sensor Calibration Table ................................... 1-49

Enabling the Sensor Calibration Table System ................... 1-49

EPM-P Series Power Meters Programming Guide Contents-9

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Making the Measurement...................................................... 1-50

Using Frequency Dependent Offset Tables ................................ 1-51

Overview ................................................................................ 1-51

Editing Frequency Dependent Offset Tables ....................... 1-53

Selecting a Frequency Dependent Offset Table ................... 1-56

Enabling A Frequency Dependent Offset Table .................. 1-56

Making The Measurement .................................................... 1-57

Setting the Range, Resolution and Averaging ........................... 1-58

Range ...................................................................................... 1-58

Resolution .............................................................................. 1-59

Averaging ...................... .................................................... ..... 1-59

Setting Offsets .............................................................................. 1-62

Channel Offsets ..................................................................... 1-62

Display Offsets ..................... ...... ....... ...... ...... ....... ...... ....... ..... 1-62

Example ................................ ...... ....... ...... ...... ....... ...... ....... ..... 1-63

Setting Measurement Limits ..................................................... 1-64

Setting Limits......................................................................... 1-65

Checking for Limit Failures .................................................. 1-66

Example .................................................................................. 1-67

Measuring Pulsed Signals .......................................................... 1-68

Using Duty Cycle ................................................................... 1-68

Making the Measurement...................................................... 1-68

Getting the Best Speed Performance ......................................... 1-71

Measurement Rate ................................. ...... ....... ...... ....... ..... 1-71

Sensor.......... ....................................... ...... ...... ....... ...... ....... ..... 1-72

Trigger Mode .......................................................................... 1-72

Output Format ....................................................................... 1-73

Units .............................. .................... ................... .................. 1-74

Command Used ...................................................................... 1-74

Fast Mode ............................................................................... 1-74

How Measurements are Calculated............................................. 1-75

Status Reporting .......................................................................... 1-76

The General Status Register Model ..................................... 1-77

How to Use Registers ............................................................. 1-79

Status Registers .................................................................... 1-84

Using the Operation Complete Commands ......................... 1-94

Saving and Recalling Power Meter Configurations ................... 1-96

How to Save and Recall a Configuration .............................. 1-96

Example Program................................................................... 1-96

Using Device Clear to Halt Measurements ................................ 1-97

An Introduction to the SCPI Language ...................................... 1-98

Syntax Conventions................................................................ 1-100

SCPI Data Types .................................................................... 1-100

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Input Message Terminators................................................... 1-106

Summary Of Commands ............................................................. 1-107

MEASurement Commands .................................................. 1-108

CALCulate Subsystem .......................................................... 1-109

CALibration Subsystem ........................................................ 1-110

DISPlay Subsystem ............................................................... 1-110

FORMat Subsystem .............................................................. 1-110

MEMory Subsystem .............................................................. 1-112

OUTPut Subsystem ............................................................... 1-112

[SENSe] Subsystem ............................................................... 1-114

STATus Subsystem ............................................................... 1-116

SYSTem Subsystem .............................................................. 1-117

TRACe Subsystem .. ...... ....... ...... ...... ....... ...... ....... ...... ....... ..... 1-117

TRIGger Subsystem ............................................................... 1-118

UNIT Subsystem ................................................................... 1- 118

SERVice Subsystem ............................................................. 1-119

................................................................................................. 1-119

SCPI Compliance Information .................................................... 1-120

Measurement Commands.................................................................. 2-1

Measurement Commands........................................................ ..... 2-2

CONFigure[1]|2|3|4?... ...... ....... ...... ...... ....... ...... ....... .................. 2-6

CONFigure[1]|2|3|4 Commands ............................................... 2-8

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-9

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]:RELative

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-12

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-14

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence

:RELative[<expected_value>[,<resolution>[,<source list>]]] ..... 2-16

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]:RATio

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-18

CONFigure[1]|2|3|4[:SCALar][:POWer:AC]:RATio:RELative

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-20

FETCh[1]|2|3|4 Queries ............................................................ 2-22

FETCh[1]|2|3|4[:SCALar][:POWer:AC]? [<expected_value>

[,<resolution>[,<source list>]]] ..................................................... 2-23

FETCh[1]|2|3|4[:SCALar][:POWer:AC]:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-25

FETCh[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-28

EPM-P Series Power Meters Programming Guide Contents-11

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FETCh[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-30

FETCh[1]|2|3|4[:SCALar][:POWer:AC]:RATio?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-33

FETCh[1]|2|3|4[:SCALar][:POWer:AC]:RATio:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-35

READ[1]|2|3|4 Commands ........................................................ 2-38

READ[1]|2|3|4[:SCALar][:POWer:AC]? [<expected_value>

[,<resolution>[,<source list>]]]..................................................... 2-39

READ[1]|2|3|4[:SCALar][:POWer:AC]:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-41

READ[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-44

READ[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-47

READ[1]|2|3|4[:SCALar][:POWer:AC]:RATio?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-50

READ[1]|2|3|4[:SCALar][:POWer:AC]:RATio:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-52

MEASure[1]|2|3|4 Commands .................................................. 2-55

MEASure[1]|2|3|4[:SCALar][:POWer:AC]?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-56

MEASure[1]|2|3|4[:SCALar][:POWer:AC]:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-58

MEASure[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-60

MEASure[1]|2|3|4[:SCALar][:POWer:AC]:DIFFerence :RELative? [<expected_value>[,<resolution>[,<source list>]]]... 2-62 MEASure[1]|2|3|4[:SCALar][:POWer:AC]:RATio?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-64

MEASure[1]|2|3|4[:SCALar][:POWer:AC]:RATio:RELative?

[<expected_value>[,<resolution>[,<source list>]]] ...................... 2-66

CALCulate Subsystem........................................................................ 3-1

CALCulate Subsystem ................................................................. 3-2

CALCulate[1]|2|3|4:FEED[1]|2 <string> ................................ 3-4

CALCulate[1]|2|3|4:GAIN Commands ............ ....... ...... ....... ..... 3-7

CALCulate[1]|2|3|4:GAIN[:MAGNitude] <numeric_value> .. 3-8

CALCulate[1]|2|3|4:GAIN:STATe <boolean> ......................... 3-10

CALCulate[1]|2|3|4:LIMit C ommands .................. .................. 3-12

CALCulate[1]|2|3|4:LIMit:CLEar:AUTo <boolean>|ONCE .. 3-13

CALCulate[1]|2|3|4:Limit:CLEar[:IMMediate] ...................... 3-15

CALCulate[1]|2|3|4LIMit:FAIL? .............................................. 3-16

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CALCulate[1]|2|3|4:LIMit:FCO unt? ........................................ 3-17

CALCulate[1]|2|3|4:LIMit:LOWer[:DATA] <numeric_value> 3-19 CALCulate[1]|2|3|4:LIMit:UPPer[:DATA] <numeric_value> 3-21

CALCulate[1]|2|3|4:LIMit:STATe <boolean> ......................... 3-23

CALCulate[1]|2|3|4:MATH C ommands........... ....... ...... ....... ..... 3-25

CALCulate[1]|2|3|4:MATH[:EXPRession] <string> ................ 3-26

CALCulate[1]|2|3|4:MATH[:EXPRessi on]:CATalog? .. ............ 3-28

CALCulate[1]|2|3|4:PHOLd :CLEar ......................................... 3-29

CALCulate[1]|2|3|4:RELative Commands ............................... 3-30

CALCulate[1]|2|3|4:RELative[:MAGNitude]:AUTO

<boolean>|ONCE ........................................................................ 3-31

CALCulate[1]|2|3|4:RELative:STATe <boolean> ................... 3-33

CALibration Subsystem..................................................................... 4-1

CALibration Subsystem ............................................................... 4-2

CALibration[1]|2[:ALL] ............................................................... 4-3

CALibration[1]|2[:ALL]?.............................................................. 4-5

CALibration[1]|2:AUTO <boolean> ............................................ 4-7

CALibration[1]|2:ECONtrol:STATe <boolean> ......................... 4-9

CALibration[1]|2:RCALi bration <bo o lea n> ................... ............ 4-10

CALibration[1]|2:RCFactor <numeric_value> .......................... 4-12

CALibration[1]|2:ZERO:AUTO <boolean> ................................ 4-14

CALibration[1]|2:ZERO:NORMal:AUTO <boolean> ................ 4-15

DISPlay Subsystem............................................................................. 5-1

DISPlay Subsystem ...................................................................... 5-2

DISPlay:CONTrast <numeric_value> ........................................ 5-3

DISPlay:ENABle <boolean> ........................................................ 5-5

DISPlay:SCReen:FORMat <character_data> ............................ 5-6

DISPlay[:WINDow[1]|2] Commands .......................................... 5-8

DISPlay[:WINDow[1]|2]:ANALog Commands ........................... 5-9

DISPlay[:WINDow[1]|2]:ANALog:LOWer <numeric_value> ... 5-10

DISPlay[:WINDow[1]|2]:ANALog:UPPer <numeric_value> .... 5-12

DISPlay[:WINDow[1]|2]:FORMat <character_data> ............... 5-14

DISPlay[:WINDow[1]|2]:METer Commands.............................. 5-16

DISPlay[:WINDow[1]|2]:METer:LOWer <numeric_value> ..... 5-17

DISPlay[:WINDow[1]|2]:METer:UPPer <numeric_value> ...... 5-19

DISPlay[:WINDow[1]|2][:NUMeric[1]|2]:RESolution

<numeric_value> .............................. ...... ....... ...... ....... ...... ....... ..... 5-21

DISPlay[:WINDow[1]|2]:SELect[1]|2 .. ....... ...... ....... .................. 5-23

DISPlay[:WINDow[1]|2][:STATe] <boolean> ............................ 5-24

DISPlay[:WINDow[1]|2]:TRACe:FEED <character_data> ....... 5-26

DISPlay[:WINDow[1]|2]:TRACe:LOWer <numeric_value>...... 5-28

DISPlay[:WINDow[1]|2]:TRACe:UPPer <numeric_value>....... 5-30

EPM-P Series Power Meters Programming Guide Contents-13

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FORMat Subsystem ............................................................................ 6-1

FORMat Subsystem...................................................................... 6-2

FORMat[:READings]:BORDer <character_data> ..................... 6-3

FORMat[:READings][:DATA] <character_data> ....................... 6-4

MEMory Subsystem............................................................................ 7-1

MEMory Subsystem ..................................................................... 7-2

MEMory:CATalog Commands.... ...... ....... ...... ...... ......................... 7-4

MEMory:CATalog[:ALL]? .......... .................................................. 7-5

MEMory:CATalog:STATe? .......................................................... 7-7

MEMory:CATalog:TABLe? ..................................................... ..... 7-8

MEMory:CLEar Commands......................................................... 7-10

MEMory:CLEar[:NAME] <character_data> .............................. 7-11

MEMory:CLEar:TABle . ............................................................... 7-12

The MEMory:FREE Commands .................................................. 7-13

MEMory:FREE[:ALL]? ................................................................ 7-14

MEMory:FREE:STATe? .............................................................. 7-15

MEMory:FREE:TABLe? .............................................................. 7-16

MEMory:NSTates? ........ .......................... ......................... ............ 7-17

The MEMory:STATe Commands................................................. 7-18

MEMory:STATe:CATalog? .......................................................... 7-19

MEMory:STATe:DEFine <character_data>,<numeric_value> . 7-20

MEMory:TABLe Commands ........................................................ 7-22

MEMory:TABLe:FREQuency <numeric_value>

{,<numeric_value>} ...................................................................... 7-23

MEMory:TABLe:FREQ uency :POI Nts? .. ...... ...... ....... ...... ....... ..... 7-26

MEMory:TABLe:GAIN[:MAGNitude]

<numeric_value>{,<numeric_value>} ......................................... 7-27

MEMory:TABLe:GAIN[:MAGNitude]:POINts? ......................... 7-29

MEMory:TABLe:MOVE <character_data>,<character_data> .. 7-30

MEMory:TABLe:SELect <character_data> ............................... 7-31

OUTput Subsystem............................................................................. 8-1

OUTPut Subsystem ..................................................................... 8-2

OUTPut:RECorder[1]|2:FEED <data_handle> ......................... 8-3

OUTPut:RECorder[1]|2:LIMit:LOWer <numeric_value> ........ 8-5

OUTPut:RECorder[1]|2:LIMit:UPPer <numeric_value> ......... 8-7

OUTPut:RECorder[1]|2:STATe <boolean> ................................ 8-9

OUTPut:ROSCillator[:STATe] <boolean> .................................. 8-10

OUTPut:TRIGger[:STATe] <boolean> ........................................ 8-11

OUTPut:TTL[1]|2:ACTive HIGH|LOW .................................... 8-12

OUTPut:TTL[1]|2:FEED <string> ............................................. 8-14

OUTPut:TTL[1|2]:STATe <boolean> ......................................... 8-16

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SENSe Subsystem................................................................................ 9-1

[SENSe] Subsystem ..................................................................... 9-2

[SENSe[1]]|SENSe2:AVERage Commands ............................... 9-5

[SENSe[1]]|SENSe2:AVERage:COUNt <numeric_value> ....... 9-6

[SENSe[1]]|SENSe2:AVERage:COUNt:AUTO <boolean> ....... 9-8

[SENSe[1]]|SENSe2:AVERage:SDETect <boolean> ................. 9-11

[SENSe[1]]|SENSe2:AVERage[:STATe] <boolean> ............. ..... 9-13

[SENSe[1]]|SENSe2:AVERage2 Commands.............................. 9-14

[SENSe[1]]|SENSe2:AVERage2:COUNt <numeric_value> ..... 9-15

SENSe[1]]|SENSe2:AVERage2[:STATe] <boolean> ................. 9-17

[SENSe[1]]|SENSe2:BANDwidth|BWIDth:VIDeo

<character_data> ......................................................................... 9-19

[SENSe[1]]|SENSe2:CORRection Commands ............... ....... ..... 9-21

SENSe[1]]|SENSe2:CORRection:CFACtor|GAIN[1][:INPut]

[:MAGNitude] <numeric_value> ................................................. 9-22

[SENSe[1]]|SENSe2:CORRection:CSET[1]|CSET2 Commands9-24 [SENSe[1]]|SENSe2:CORRection:CSET[1]|CSET2[:SELect]

<string> ........................................................................................ 9-25

[SENSe[1]]|SENSe2:CORRection:CSET[1]|CSET2:STATe

<boolean> ..................................................................................... 9-27

[SENSe[1]]|SENSe2:CORRection:DCYCle|GAIN3 Commands 9-29 [SENSe[1]]|SENSe2:CORRection:DCYCle|GAIN3[:INPut]

[:MAGNitude] <numeric_value> ................................................. 9-30

[SENSe[1]]|SENSe2:CORRection:DCYCle|GAIN3:STATe

<boolean> ..................................................................................... 9-33

[SENSe[1]]|SENSe2:CORRection:FDOFfset|GAIN4[:INPut]

[:MAGNitude]? ............................................................................. 9-35

[SENSe[1]]|SENSe2:CORRection:GAIN2 Commands .............. 9-36

[SENSe[1]]|SENSe2:CORRection:GAIN2:STATe <boolean> ... 9-37 [SENSe[1]]|SENSe2:CORRection:GAIN2[:INPut]

[:MAGNitude] <numeric_value> ................................................. 9-39

[SENSe[1]]|SENSe2:DETector:F UNCtion <character_data> .. 9-41 [SENSe[1]]|SENSe2:FREQuency[:CW|:FIXed]

numeric_value> ...................................... ...................................... 9-43

[SENSe[1]]|SENSe2:MRATe <character_data> ........................ 9-45

[SENSe[1]]|SENSe2:POWer:AC:RANGe <numeric_value> ..... 9-47

[SENSe[1]]|SENSe2:POWer:AC:RANGe:AUTO <boolean> ..... 9-48

[SENSe[1]]|SENSe2:SPEed <numeric_value> .......................... 9-50

SENSe[1]]|SENSe2:SWEep[1]|2|3|4 Commands ................... 9-52

[SENSe[1]]|SENSe2:SWEep[1]|2|3|4:OFFSet:TIME

<numeric_value> .............................. ...... ....... ...... ......................... 9-53

EPM-P Series Power Meters Programming Guide Contents-15

Page 18

[SENSe[1]]|SENSe2:SWEep[1]|2|3|4:TIME <numeric_value>

................................. ...................................................................... 9-55

SENSe[1]]|SENSe2:TRACe Commands ..................................... 9-57

SENSe[1]|2:TRACe:LIMit:LOWer <numeric_value> ................ 9-58

SENSe[1]|2:TRACe:LIMit:UPPer <numeric_value> ................. 9-60

[SENSe[1]]|SENSe2:TRACe:OFFSet:TIME <numeric_value>. 9-62

[SENSe[1]]|SENSe2:TRACe:TIME <numeric_value> .............. 9-64

[SENSe[1]]|SENSe2:TRACe:UNIT <character_data> .............. 9-66

[SENSe[1]]|SENSe2:V2P ATYPe|DTYPe ................................. 9-67

STATus Subsystem ........................................................................... 10-1

STATus Subsystem .................................................................... 10-2

Status Register Set Commands ................................................. 10-4

Device Status Register Sets ...................................................... 10-8

Operation Register Sets ............................................................. 10-10

STATus:OPERation.................................................................... 10-11

STATus:OPERation:CALibrating[:SUMMary]......................... 10-12

STATus:OPERation:LLFail[:SUMMary]................................... 10-13

STATus:OPERation:MEASuring[:SUMMary].......................... 10-14

STATus:OPERation:SENSe[:SUMMary] .................................. 10-15

STATus:OPERation:TRIGger[:SUMMary] ............................... 10-16

STATus:OPERation:ULFail[:SUMMary].................................. 10-17

STATus:PRESet.......................................................................... 10-18

Questionable Register Sets .................... ...... ...... ....... ...... .......... 1 0-19

STATus:QUEStionable . .......................................................... ... 10-20

STATus:QUEStionable:CALibration[:SUMMary] ................... 10-21

STATus:QUEStionable:PO Wer[:SUMMary] ............................ 10-22

SYSTem Subsystem........................................................................... 11-1

SYSTem Subsystem ................................................................... 11-2

SYSTem:COMMunicate:GPIB[:SELF]:ADDRess

<numeric_value> ....................................................................... 11-4

SYStem:COMMunicate:Seri al C omma nds ........ ....... ................ 11-6

SYSTem:COMMunicate:SERial:CONTrol:DTR <boolean> ..... 11-7

SYSTem:COMMunicate:SERial:CONTrol:RTS <boolean> ..... 11-8

SYSTem:COMMunicate:SERial[:RECeive]:BAUD

<numeric_value> ....................................................................... 11-9

SYSTem:COMMunicate:SERial[:RECeive]:BITs

<numeric_value> ....................................................................... 11-11

SYSTem:COMMunicate:SERial[:RECeive]:PACE XON

|NONE ....................................................................................... 11-13

SYSTem:COMMunicate:SERial[:RECeive]:PARity[:TYPE]

EVEN|ODD|ZERO|ONE|NONE ........................... ................ 11-14

Contents-16 EPM-P Series Power Meters Programming Guide

Page 19

SYSTem:COMMunicate:SERial[:RECeive]:SBITs

<numeric_value> .............................. ...... ....... ...... ....... ...... ....... ... 11-16

SYSTem:COMMunicate:SERial:T RANsmit:AUTO? ................ 11-17

SYSTem:COMMunicate:SERial:T RANsmit:BAUD

<numeric_value> .............................. ...... ....... ...... ....... ...... ....... ... 11-18

SYSTem:COMMunicate:SERial:T RANsmit:BITs

<numeric_value> ........................................................................ 11-20

SYSTem:COMMunicate:SERial:TRANsmit:ECHO <boolean> 11-21 SYSTem:COMMunicate:SERial:TRANsmit:PACE XON

|NONE ....................................................................................... 11-23

SYSTem:COMMunicate:SERial:TRANsmit:PARity[:TYPE]

EVEN|ODD|ZERO|ONE|NONE ........................... ................ 11-24

SYSTem:COMMunicate:SERial:T RANsmit:SBITs

<numeric_value> ........................................................................ 11-26

SYSTem:HELP:HEADers? ........................................................ 11-28

SYStem:LOCal ........................................................................... 11-29

SYSTem:PRESet <character_data>........................................... 11-30

Preset Values........................................................................ 11-32

SYSTem:REMote ........................................................................ 11-60

SYSTem:RINTerface GPIB|RS232|RS422 ............................. 11-61

SYSTem:RWLock .......... ............................................................. 11-62

SYSTem:VERSion? .................................................................... 11-63

TRACe Subsystem............................................................................. 12-1

TRACe Subsystem . ....... ...... ....... ...... ...... ....... ............................. 12-2

TRACe[1]|2[:DATA]? <character_data> .................................. 12-3

TRACe[1]|2:STATe <boolean> ................................................. 12-5

TRACe[1]|2:UNIT <character_data> ... ....... ...... ....... ...... ....... ... 12-6

TRIGger Subsystem.......................................................................... 13-1

TRIGger Subsystem ................................................................... 13-2

ABORt[1]|2] ........................ ................................ ....................... 13-3

INITiate Commands .................................................................. 13-4

INITiate[1]|2:CONTinuous <boolean> ..................................... 13-5

INITiate[1]|2[:IMMediate] ....................................................... 13-7

INITiate:CONTinuous:ALL <boolean> .................................... 13-8

INITiate:CONTinuous:SEQuence[1]|2 <bo o lean> .................. 13-10

INITiate[:IMMediate]:ALL . .......................... .......................... ... 1 3-12

INITiate[:IMMediate]:SEQuence[1]|2 ..................................... 13-13

TRIGger Commands .................................................................. 13-14

TRIGger[1]|2:DELay:AUTO <boolean> ................................... 13-15

TRIGger[1]|2[:IMMediate] ....................................................... 13-17

TRIGger[1]|2:SOURce BUS|EXTernal|HOLD|IMMediate

|INTernal[[1]|2] ........................ ............................................. ... 13-18

EPM-P Series Power Meters Programming Guide Contents-17

Page 20

TRIGger[:SEQuence]:DELay <numeric_value> ....................... 13-20

TRIGger[:SEQuence]:HOLDoff <numeric_value> ... ...... ....... ... 13-22

TRIGger[:SEQuence]:HYSTeresis <numeric_value> .............. 13-24

TRIGger[:SEQuence]:LEVel <numeric_value> ........................ 13-26

TRIGger[:SEQuence]:LEVel:AUTO <boolean> ........................ 13-28

TRIGger[:SEQuence]:SLOPe <character_data> ...................... 13-30

TRIGger[:SEQuence[1]|2]:COUNt <numeric_value> ... ....... ... 13-32

TRIGger[:SEQuence[1]|2]:DELay:AUTO <boolean> .............. 13-34

TRIGger[:SEQuence[1]|2]:IMMediate ..................................... 13-36

TRIGger[:SEQuence[1]|2]:SOURce BUS|EXTernal|HOLD

|IMMediate|INTernal[[1]|2] ................................................... 13-37

UNIT Subsystem................................................................................ 14-1

UNIT Subsystem ........................................................................ 14-2

UNIT[1]|2|3|4:POWer <amplitude_unit> .............................. 14-3

UNIT[1]|2|3|4:POWer:RATio <ratio_unit> ........................... 14-6

SERVice Subsystem................... ....................................................... 15-1

SERVice Subsystem ................................................................... 15-2

SERVice:BIST:CALibrator <boolean>....................................... 15-3

SERVice:BIST:FPATH[1]|2:MEASure?.................................... 15-4

SERVice:BIST:FPATH[1]|2:REFerence <numeric_value> ..... 15-5

SERVice:BIST:FPATH[1]|2:STATe <boolean> ........................ 15-6

SERVice:BIST:TBASe:STAT e <boo lea n>.................................. 15-7

SERVice:BIST:TRIGger:LE Vel :ST ATe............................ ....... ... 15-8

SERVice:BIST:TRIGger:TE ST ? ................................................. 1 5-9

SERVice:OPTion <character_data> .......................................... 15-10

SERVice:SENSor[1]|2:CALFactor <cal_factor_data> ............. 15-11

SERVice:SENSor[1]|2:CDATe? ................................................ 15-13

SERVice:SENSor[1]|2:CORRections:STATe <boolean>.......... 15-14

SERVice:SENSor[1]|2:CPLace? ............................................... 15-16

SERVice:SENSor[1]|2:FREQuency:MAXimum? ..................... 15-17

SERVice:SENSor[1]|2:FREQuency:MINimum? ...................... 15-18

SERVice:SENSor[1]|2:PCALFactor <cal_factor_data> .......... 15-19

SERVice:SENSor[1]|2:POWer:AVERage:MAXimum? .. .......... 15-20

SERVice:SENSor[1]|2:POWer:PEAK:MAXimum? ................. 15-21

SERVice:SENSor[1]|2:POWer:USABle:MAXimum? ..... ....... ... 15-22

SERVice:SENSor[1]|2:POWer:USABle:MINimum? ............... 15-23

SERVice:SENSor[1]|2:RADC? ............... ................... ................ 15-24

SERVice:SENSor[1]|2:SNUMber? ........................................... 15-25

SERVice:SENSor[1]|2:TNUMber? ........................................... 15-26

SERVice:SENSor[1]|2:TYPE? .................................................. 15-27

SERVice:SNUMber <character_data> ...................................... 15-28

SERVice:VERSion:PROCessor <character_data> ................... 15-29

Contents-18 EPM-P Series Power Meters Programming Guide

Page 21

SERVice:VERSion:SYSTem <character_ dat a> ..................... ... 15-30

IEEE488.2 Command Reference.................................................... 16-1

IEEE-488 Compliance Information ........................................... 16-2

Universal Commands ................................................................. 16-3

DCL ...................................................................................... 16-3

GET ...................................................................................... 16-3

GTL ...................................................................................... 16-3

LLO ...................................................................................... 16-3

PPC ................................ ................... .................... ................ 16-4

PPD ...................................................................................... 16-4

PPE ................................ ................... .................... ................ 16-4

PPU ...................................................................................... 16-5

SDC ....................................................................................... 16-5

SPD........................................................................................ 16-5

SPE........................................................................................ 16-6

*CLS ........................................................................................... 16-7

*DDT <arbitrary block program data>

|<string program data> ............................................................ 16-8

*ESE <NRf> ............................................................................... 16-10

*ESR? ............................. ................... ................... .................... ... 16-11

*IDN? ............................. .......................................................... ... 16-12

*OPC .............................. .......................................................... ... 16-13

*OPT? ......................................................................................... 16-14

*RCL <NRf> ............................................................................... 16-15

*RST ........................................................................................... 16-16

*SAV <NRf> ............................................................................... 16-17

*SRE <NRf> ............................................................................... 16-18

*STB? ...................... ............................................. ....................... 16-20

*TRG .............................. .......................................................... ... 16-22

*TST? ............................. ............................................................. 16-23

*WAI ........................................................................................... 16-24

Calibration Factor Block Layout ...................................................A-1

Calibration Factor Block Layout..................................................A-2

EPM-P Series Power Meters Programming Guide Contents-19

Page 22

Contents-20 EPM-P Series Power Meters Programming Guide

Page 23

List of Tables

Page

1-1 MEASure? and CONFigure Preset States ............................... 1-8

1-2 Range of Values for Window Limits ......................................... 1-65

1-3 Bit Definitions - Status Byte Register...................................... 1-85

1-4 Bit Definitions - Standard Event Register............................... 1-87

3-1 Measurement Units.................................... ...... ....... ...... ....... ..... 3-19

3-2 Measurement Units.................................... ...... ....... ...... ....... ..... 3-21

5-1 Measurement Units.................................... ...... ....... ...... ....... ..... 5-10

5-2 Measurement Units.................................... ...... ....... ...... ....... ..... 5-12

5-3 Measurement Units.................................... ...... ....... ...... ....... ..... 5-17

5-4 Measurement Units.................................... ...... ....... ...... ....... ..... 5-19

5-5 Measurement Units.................................... ...... ....... ...... ....... ..... 5-28

5-6 Measurement Units.................................... ...... ....... ...... ....... ..... 5-30

9-1 Measurement Units.................................... ...... ....... ...... ....... ..... 9-58

9-2 Measurement Units.................................... ...... ....... ...... ....... ..... 9-60

10-1 Commands and events affecting Status Registers ............... 10-2

11-1 DEFault: Power Meter Presets............................................... 11-32

11-2 GSM900: Power Meter Presets............................................... 11-36

11-3 GSM900: Power Meter Presets: Window/

Measurement Settings ............................................................ 11-37

11-4 GSM900: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-38

11-5 EDGE: Power Meter Presets................................................... 11-39

11-6 EDGE: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-40

11-7 EDGE: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-41

11-8 NADC: Power Meter Presets................................................... 11-42

11-9 NADC: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-43

11-10 NADC: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-44

11-11 BLUetooth: Power Meter Presets ........................................... 11-45

11-12 BLUetooth: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-46

EPM-P Series Power Meters Programming Guide Contents-21

Page 24

11-13 BLUetooth: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-47

11-14 CDMAone: Power Meter Presets ............................................ 11-48

11-15 CDMAone: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-49

11-16 CDMAone: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-50

11-17 WCDMA: Power Meter Presets............................................... 11-51

11-18 WCDMA: Power Meter Prese ts: Window/Measurement

Settings .................................................................................... 11-52

11-19 WCDMA: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-53

11-20 CDMA2000: Power Meter Presets.......................................... 11-54

11-21 CDMA2000: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-55

11-22 CDMA2000: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-56

11-23 iDEN: Power Meter Presets.................................................... 11-57

11-24 iDEN: Power Meter Presets: Window/Measurement

Settings .................................................................................... 11-58

11-25 iDEN: Power Meter Presets For Secondary Channel

Sensors ..................................................................................... 11-59

16-1 PPD Mapping........................................................................... 16-4

16-2 PPE Mapping........................................................................... 16-4

16-3 *ESE Mapping......................................................................... 16-10

16-4 *ESR? Mapping........................................................................ 16-11

16-5 *SRE Mapping......................................................................... 16-18

16-6 *STB? Mapping........................................................................ 16-20

Contents-22 EPM-P Series Power Meters Programming Guide

Page 25

List of Figures

Page

1-1 Sensor Calibration Tables......................................................... 1-42

1-2 Frequency Dependent Offset Tables......................................... 1-52

1-3 Averaged Readings.................................................................... 1-60

1-4 Averaging Range Hysteresis..................................................... 1-60

1-5 Limits Checking Application..................................................... 1-64

1-6 Limits Checking Results ........................................................... 1-65

1-7 Pulsed Signal ............................................................................. 1-69

1-8 How Measurements are Calculated.......................................... 1-75

1-9 Generalized Status Register Model.......................................... 1-77

1-10 Typical Status Register Bit Changes........................................ 1-78

1-11 Status System............................................................................ 1-84

3-1 CALCulate Block ....................................................................... 3-2

9-1 Averaged Readings.................................................................... 9-8

11-1 A Trace Display Of The Active Timeslots ............................. 11-42

EPM-P Series Power Meters Programming Guide Contents-23

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Contents-24 EPM-P Series Power Meters Programming Guide

Page 27

Power Meter Remote Operation

Page 28

Power Meter Remote Operation

Introduction

This chapter describes the parameters which configure the power meter and help you determine settings to optimize performance. It contains the following sections:

“Configuring the Remote Interface”, on page 1-3. “Zeroing and Calibrating the Power Meter”, on page 1-5. “Making Measurements”, on page 1-8. “Making Measurements on Wireless Communication Standards”, on

page 1-24 “Using Sensor Calibration Tables”, on page 1-41. “Using Frequency Dependent Offset Tables”, on page 1-51 “Setting the Range, Resolution and Averaging”, on page 1-58. “Setting Offsets”, on page 1-62. “Setting Measurement Limits”, on page 1-64. “Measuring Pulsed Signals”, on page 1-68. “END”, on page 1-70. “Getting the Best Speed Performance”, on page 1-71. “How Measurements are Calculated”, on page 1-75. “Status Reporting”, on page 1-76. “Saving and Recalling Power Meter Configurations”, on page 1-96. “Using Device Clear to Halt Measurements”, on page 1-97. “An Introduction to the SCPI Language”, on page 1-98. “Summary Of Commands”, on page 1-107. “SCPI Compliance Information”, on page 1-120.

1-2 EPM-P Series Power Meters Programming Guide

Page 29

Pow er Meter Remote Operatio n

Configuring the Remote Interface

This section describes how to configure the GPIB, RS232 and RS422 remote interfaces.

Interface el ection

You can choose to control the power meter remotely using either the GPIB , RS232 or RS422 standard interfaces.

For information on selecting the remote interface manually from the front panel, refer to the EPM-P Series Power Meters User’s Guide.

To select the interface remotely use the:

• SYSTem:RINTerface command To query the current remote interface selection use the:

• SYSTem:RINTerface? command

GPIB Address

Each device on the GPIB (IEEE-488) interface must have a unique address. You can set the power meter’s address to any value between 0 and 30. The address is set to 13 when the power meter is shipped from the factory.

The address is stored in non-volatile memory, and does not change when the power meter is switched off, or after a remote interface reset.

Your GPIB bus controller has its own address. Avoid using the bus controller’s address for any instrument on the interface bus. Agilent controllers generally use address 21.

For information on setting the GPIB address manually from the front panel, refer to the EPM-P Series Power Meters User’s Guide.

To set the GPIB address fr om the remote interface use the:

• SYSTem:COMMunicate:GPIB:ADDRess command. To query the GPIB address from the remote interface use the;

• SYSTem:COMMunicate:GPIB:ADDRess? query.

EPM-P Series Power Meters Programming Guide 1-3

Page 30

Power Meter Remote Operation

Configuring the Remote Interface

RS232/RS422 Configuration

The RS232/RS422 serial port on the rear panel is a nine pin D-type connector configured as a DTE (Data Terminal Equipment). For pin-ou t information and cable length restrictions refer to the EPM-P Series P ower Meters User’s Guide.

You can set the baud rate, word length, parity, number of stop bits, software and hardware pacing, either remotely or from the front panel. For front panel operation refer to the EPM-P Series Power Meter User’s Guide. For remote operation use the following commands:

SYSTem:COMMunicate:SERial:CONTrol:DTR SYSTem:COMMunicate:SERial:CONTrol:RTS SYSTem:COMMunicate:SERial[:RECeive]:BAUD SYSTem:COMMunicate:SERial[:RECeive]:BITs SYSTem:COMMunicate:SERial[:RECeive]:PACE SYSTem:COMMunicate:SERial[:RECeive]:PARity[:TYPE] SYSTem:COMMunicate:SERial[:RECeive]:SBITs SYSTem:COMMunicate:SERIal:TRANsmit:AUTO? SYSTem:COMMunicate:SERial:TRANsmit:BAUD SYSTem:COMMunicate:SERial:TRANsmit:BITs SYSTem:COMMunicate:SERial:TRANsmit:ECHO SYSTem:COMMunicate:SERial:TRANsmit:PACE SYSTem:COMMunicate:SERial:TRANsmit:PARity[:TYPE] SYSTem:COMMunicate:SERial:TRANsmit:SBITs

1-4 EPM-P Series Power Meters Programming Guide

Page 31

Pow er Meter Remote Operatio n

Zeroing and Calibrating the Power Meter

This section describes how to zero and calibrate the power meter. The calibration and zeroing commands are overlapped commands refer to

“Using the Operation Complete Commands”, on page 1-94 to determine when the commands are complete.

Zeroing

Zeroing adjusts the power meter’s specified channel for a zero power reading with no power applied to the power sensor.

The command used to zero the power meter is:

CALibration[1|2]:ZERO:AUTO ONCE

The command assumes that there is no power being applied to the sensor. It turns the power reference oscillator off, then after zeroing, returns the power reference oscillator to the same state it was in prior to the command being received.

When to Zero?

Zeroing of the power meter is recommended:

•when a 5

• when you change the power sensor.

• every 24 hours.

• prior to measuring low level signals. For example, 10 dB above the

lowest specified power for your power sensor.

C change in temperature occurs.

Calibration

Calibration sets the gain of the power meter using a 50 MHz 1 mW calibrator as a traceable power reference. The power meter’s POWER REF output or a suitable external reference is used as the signal source for calibration. An essential part of calibrating is setting the correct reference calibration factor for the power sensor you are using. The 8480 series power sensors require you to set the reference calibration factor. All E-series power sensors set the reference calibration factor automatically. Offset, relative and duty cycle settings are ignored during calibration.

EPM-P Series Power Meters Programming Guide 1-5

Page 32

Power Meter Remote Operation

Zeroing and Calibrating the Power Meter

The command used to calibrate the power meter is:

CALibration[1|2]:AUTO ONCE

The command assumes that the power sensor is connected to a 1 mW reference signal. It turns the power reference oscillator on, then after calibrating, returns the power reference oscillator to the same state it was in prior to the command being received. It is recommended that you zero the power meter before calibrating.

Calibration Sequence

This feature allows you to perform a complete calibration sequence with a single query. The query is:

CALibration[1|2][:ALL]?

The query assumes that the power sensor is connected to the power reference oscillator. It turns the power reference oscillator on, then after calibrating, returns the power reference oscillator to the same state it was in prior to the command being received. The calibration sequence consists of:

• Zeroing the power meter (CALibration[1|2]:ZERO:AUTO ONCE), and

• calibrating the power meter (CALibration[1|2]:AUTO ONCE). The query enters a number into the output buffer when the sequence is

complete. If the result is 0 the sequence was successful . If the result is 1 the sequence failed. Refer to CALibration[1]|2[:ALL]? on page 4-5 for further information.

Note The CALibration[1|2][:ALL] command is identical to the

CALibration[1|2][:ALL]? query except that no number is

returned to indicate th e outcome of the seq uence . You can examine the Questionable Status Register or the error queue to discover if the sequence has passed or failed. Refer to “Status Reporting”, on page 1-76 for further information.

1-6 EPM-P Series Power Meters Programming Guide

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Pow er Meter Remote Operatio n

Zeroing and Calibrating the Power Meter

Setting the Reference Calibration Factor

All the 8480 series power sensors require you to set the reference calibration factor. The reference calibration factor can be set by:

• entering the value into the power meter using the

CALibrate[1|2]:RCFactor command.

• selecting and enabling the sensor calibration table. The reference

calibration factor is automatically set by the power meter using the reference calibration factor stored in the sensor calibration table. See “Using Sensor Calibration Tables”, on page 1-41 for further information.

Examples

a) To enter a reference calibration factor of 98.7% for channel A, you

should use the following command:

CAL:RCF 98.7PCT

This overrides any RCF previously set by selecting a sensor

calibration table.

b) To automatically set the reference calibration factor, you have to

use a sensor calibration table as described in “Using Sensor

Calibration Tables”, on page 1-41. To select and enable the table

use the following commands:

[SENSe[1]]|SENSe2:CORRection:CSET1:SELect <string>

[SENSe[1]]|SENSe2:CORRection:CSET1:STATe ON

When the sensor calibration table is selected the RCF from the

table overrides any value previously set.

Querying the Reference Calibration Factor

To determine the current reference calibration factor, use the following command:

CALibration[1|2]:RCFactor?

EPM-P Series Power Meters Programming Guide 1-7

Page 34

Power Meter Remote Operation

Making Measurements

The MEASure? and CONFigure commands provide the most straight-forward method to program the power meter for measurement s.

You can select the measurement’s expected power level, resolution and with the E4417A the measurement type (that is single channel, difference or ratio measurements) all in one command. The power meter automatically preset s other measuremen t parameters to default valu es as shown in Table 1-1.

Table 1-1: MEASure? and CONFigure Preset States

Command

Trigger source (TRIGger:SOURce)

Filter (SENSe:AVERage:COUNt:AUTO)

Filter state (SENSe:AVERage:STATe)

Trigger cycle (INITiate:CONTinuous)

Trigger Delay (TRIGger:DELay:AUTO)

An alternative method to program the power meter is to use the lower level commands. The advantage of using the lower level commands over the CONFigure command is that they give you more precise control of the power meter. As shown in Table 1-1 the CONFigure command presets various states in the power mete r. It may be likely that you do not want to preset these states. Refer to “Using the Lower Level Commands”, on page 1-23 for further information.

MEASure? and CONFigure

Setting

Immediate

Off

1-8 EPM-P Series Power Meters Programming Guide

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Pow er Meter Remote Operatio n

Making Measurements

Using MEASure?

The simplest way to program the power meter for measurements is by using the MEASure? query. However, this command does not offer much flexibility. When you execute the command, the power meter selects the best settings for the requested configuration and immediately performs the measurement. You cannot change any settings (other than the expected power value, resolution and with the E4417A the measurement type) before the measurement is taken. This means you cannot fine tune the measurement, for example, you cannot change the filter length. To make more flexible and accurate measurements use the CONFIGure command. The measurement results are sent to the output buffer. MEASure? is a compound command which is equivalent to an ABORT, followed by a CONFigure, followed by a READ?.

MEASure? Examples

The following commands show a few examples of how to use the MEASure? query to make a measurement. It is advisable to read through these examples in order as they become increasingly more detailed. These examples configure the power meter for a measurement (as described in each individual example), automatically place the power meter in the

“wait-for-trigger” state, internally trigger the power meter to take one reading, and then sends the reading to the output buffer.

These examples give an overview of the MEASure? query. For further information on the MEASure? commands refer to the section “MEASure[1]|2|3|4 Commands” starting on page 2-55.

Example 1 - The Simplest Method

The following commands show the simplest method of making single channel (for example A or B) measurements. Using MEAS1? will result in an upper window measurement, and MEAS2? in a lower window measurement. The channel associated with the window can be set using the source list parameter (see example 2), or will default as in this example (See also page 1-12).

specifies window

MEAS1? MEAS2?

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Example 2 - Specifying the Source List Parameter

The MEASure command has three optional parameters, an expe cted power value, a resolution and a source list. These parameters must be entered in the specified order. If parameters are omitted, they will default from the right. The parameter DEFault is used as a place holder.

The following example uses the source list parameter to specify the measurement channel as channel A. The e xpected power and resolution parameters are defaulted, leaving them at their current settings. The measurement is carried out on the upper window.

specifies window specifies channel

MEAS1? DEF,DEF,(@1)

The operation of the MEAS1? command when the source list parameter is defaulted is described in the no te on page 1-12.

Note For the E4416A it is not necessary to specify a channel as only one

channel is available.

Example 3 - Specifying the Expected Power Parameter

The previous example details the three optional parameters which can be used with the MEASure? command. The first optional parameter is used to enter an expected power value. Entering this parameter is only relev ant if you are using an E-series power sensor. The value entered determin es

which of the power sensor’ s two range s is used for the measure ment. If the current setting of the power sensor’s range is no longer valid for the new measurement, specifying the expected power value decreases the time taken to obtain a result.

The following example uses the expected value parameter to specify a value of -50 dBm. This selects the power sensor’s lower range (refer to “Range”, on page 1-58 for details of the range breaks). The resolution parameter is defaulted, leaving it at its current setting. The source list parameter specifies a channel B measurement. The measurement is displayed on the lower window.

specifies expe cted power value

specifies window specifies channel

MEAS2? -50,DEF,(@2)

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Example 4 - Specifying the Resolution Parameter

The previous examples detailed the use of the expected value and source list parameters. The resolution parameter is used to set the resolution of the specified window. This parameter does not affect the resolution of the GPIB data, however it does affect the auto averaging setting (refer to Figure 1-3 on page 1-60).

Since the filter length used for a channel with auto-averaging enabled is dependent on the window resolution setting, a conflict arises when a given channel is set up in both windows and the resolution settings are different. In this case, the higher resolution setting is used to determine the filter length.

The following example uses the resolution parameter to specify a resolution setting of 3. This setting represents 3 significant digits if the measurement suffix is W or %, and 0.01 dB if the suffix is dB or dBm.

Refer to Chapter 2, “Measurement Commands” for further details on the resolution parameter. The expected power and source list parameters are defaulted in the example . The expect ed power val ue will be left uncha nged at its current setting. The source list parameter will be defaulted as described in the note on page 1-12. Note that as the source list parameter is the last specified parameter you do not have to specify DEF. The measurement is carried out on the upper window.

specifies window

specifies resolution setting

MEAS1? DEF,3

Example 5 - Making a Difference Measurement

The following command can only be carried out on the EPM-442A. It queries the lower window to make a difference measurement of channel B - channel A. The expected power and resolution parameters are defaulted, leaving them at their current settings.

specifies between which channels

specifies window

the difference is calculated

MEAS2:POW:AC:DIFF? DEF,DEF,(@2),(@1)

Channel B - A

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Example 6 - Making a Ratio Measurement

The following command can only be carried out on the E4417A. It queries the upper window to make a ratio measurement of channel A/B. The expected power and resolution parameters are defaulted, leaving them at their current settings.

specifies window

Note E4417A only.

The operation of the MEASure? command when the source list parameter is defaulted depends on the current setup of the window concerned (for example, A, B, A/B, A-B etc.) and on the particular command used (for example, MEAS[:POW][:AC]? and MEAS:POW:AC:RAT?).

This means that when the source list parameter is defaulted, there are a number of possibilities.

Command Current Window Setup Measurement

MEAS1[:POW][AC]? Upper Window: A A

specifies the relationship of the channels in the ratio

MEAS1:POW:AC:RAT? DEF,DEF,(@1),(@2)

Channel A / B

BB Any Other A

MEAS2[:POW][AC]? Lower Window: A A

BB Any Other B

MEAS1:POW:AC:RAT Upper Window: A/B A/B

B/A B/A Any Other A/B

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Command Current Window Setup Measurement

MEAS2:POW:AC:RAT Lower Window: A/B

B/A Any Other

MEAS1:POW:AC:DIFF? Upper Window: A-B

B-A Any Other

MEAS2:POW:AC:DIFF? Lower Window: A-B

B-A Any Other

A/B B/A A/B A-B B-A A-B A-B B-A A-B

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Using the CONFigure Command

When you execute this command, the po wer meter presets the best settings for the requested configuration (like the MEASure? query). However, the measurement is not automatically started and you can change measurement parameters before making measurements. This

allows you to incrementally change the power meter’s configuration from the preset conditions. The power meter offers a variety of low-level commands in the SENSe, CALCulate, and TRIGger subsystems. For example, if you want to change the averaging use the [SENSe[1]]|SENSe2:AVERage:COUNt command.

Use the INITiate or READ? query to initiate the measurement.

Using READ?

CONFigure does not take the measurement. One method of obtaining a result is to use the READ? query. The READ? query takes the measurement using the parameters set by the CONFigure command then se nds the reading to the output buffer. Using the READ? query will obtain new data.

Using INITiate and FETCh?

CONFigure does not take the measurement. One method of obtaining the result is to use the INITiate and FETCh? commands. The INITiate command causes the measurement to be taken. The FETCh? query retrieves a reading when the measurement is complete, and sends the reading to the output buffer. FETCh? can be used to display the measurement results in a number of different formats (for example, A/B and B/A) without taking fresh data for each measurement.

CONFigure Examples

The following program segments show how to use the READ? command and the INITiate and FETCh? commands with CONFigure to make measurements.

It is advisable to read through these examples in order as they become increasingly more detailed.

These examples g ive an ov erview of th e CONFigure command. F or f urther information on the CONFigure commands refer to Chapter 2, “Measurement Commands”.

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Example 1 - The Simplest Method

The following program segments show the simplest method of querying

the upper and lower window’s measurement re sults respectively.

Using READ?

*RST Reset instrument CONF1 Configure upper window - defaults to a channel A

measurement

READ1? Take upper window (channel A) measurement *RST Reset instrument

CONF2 Configure the lower window - defaults to channel A

(E4416A), Channel B (E4417A) measurement

READ2? Take lower window measurement (channel A on

E4416A, B on E4417A)

Using INITiate and FETCh?

*RST Reset instrument CONF1 Configure upper window - defaults to a channel A

measurement

INIT1 Causes channel A to make a measurement FETC1? Retrieves the upper window’s measurement

For the E4416A only:

*RST Reset instrument CONF2 Configure lower window - E4416A defaults to

channel A

INIT1? Causes channel A to make measurement FETC2? Retrieves the lower window’s measurement

For the E4417A only:

*RST Reset instrument CONF2 Configure lower window INIT2? Causes channel B to make measurement FETC2? Retrieves the lower window’s measurement

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Example 2 - Specifying the Source List Parameter

The CONFigure and READ? commands have three optional parameters, an expected power value, a resolution and a source list. Thes e parameters must be entered in the specified order . If parameters are omitted, they will default from the right. The parameter DEFault is used as a place holder.

The following examples use the source list parameter to specify the measurement channel as channel A. The e xpected power and resolution parameters are defaulted, leaving them at their current settings. The measurement is carried out on the upper window.

Although the READ? and FETCh? queries have three optional parameters it is not necessary t o define them as shown in these examples. If they are defined they must be identical to those defined in the CONFigure command otherwise an error occurs.

Note For the EPM-441A it is not necessary to specify a channel as only

one channel is available.

Using READ?

ABOR1 Aborts channel A CONF1 DEF,DEF,(@1) Configures the upper window to

make a channel A measurement using the current expected power and resolution settings.

READ1? Takes the upper window’s

measurement.

Using INITiate and FETCh?

ABOR1 Aborts channel A CONF1 DEF,DEF,(@1) Configures the upper window to

make a channel A measurement using the current expected power and resolution settings.

INIT1 Causes channel A to make a

measurement.

FETC1? Retrieves the upper window’s

measurement.

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Example 3 - Specifying the Expected Power Parameter

The previous example details the three optional parameters which can be used with the CONFigure and READ? commands. The first optional parameter is used to enter an expected power value. Entering this parameter is only relevant if you are using an E-series power sensor. The

value entered determines which of the power sensor’s two ranges is used for the measurement. If the current setting of the power sensor’s range is no longer valid for the new measurement, specifying the expected power value decreases the time taken to obtain a result.

The following example uses the expected value parameter to specify a value of -50 dBm. This selects the power meter’s lower range (refe r to “Range”, on page 1-58 for details of the range breaks). The resolution parameter is defaulted, leaving it at its current setting. The source list parameter specifies a channel B measurement. The measurement is carried out on the upper window.

Using READ?

ABOR2 Aborts channel B CONF1 -50,DEF,(@2) Configures the upper window to

make a channel B measurement using an expected power of

-50 dBm and the current resolution setting.

READ1? Takes the upper window’s

measurement.

Some fine tuning of measurements can be carried out using the CONFigure and READ? commands. For example, in the above program segment some fine tuning can be carried out by setting the filter length to 1024 and the trigger delay off.

ABOR2 CONF1 -50,DEF,(@2) SENS2:AVER:COUN 1024 TRIG2:DEL:AUTO OFF READ1?

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Using INITiate and FETCh?

ABOR2 Aborts channel B CONF1 -50,DEF,(@2) Configures the upper window to

make a channel B measurement using an expected power of

-50 dBm and the current resolution setting.

INIT2 Causes channel B to make a

measurement.

FETC1? Retrieves the upper window’s

measurement.

Some fine tuning of measurements can be carried out using the CONFigure command and INITiate and FETCh? commands. F or example, in the above program segment some fine tuning can be carried out by setting the filter length to 1024 and the trigger delay off.

ABOR2 CONF1 -50,DEF,(@2) SENS2:AVER:COUN 1024 TRIG2:DEL:AUTO OFF INIT2 FETC1?

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Example 4 - Specifying the Resolution Parameter

Chapter 2, “Measurement Commands”). Also, in this example the expected power and source list parameters are defaulted. The expected power value will be left unchanged at its current setting. The source list parameter will be defaulted as described in the note on page 1-12. Note that as the source list parameter is the last specified parameter you do not have to specify DEF.

Using READ?

ABOR1 Aborts channel A. CONF1 DEF,3 Configures the upper window to make a

measurement using the current setting of the expected power and source list and a resolution setting of 3.

READ1? Takes the upper window’ s measurement. This will be

a channel A or B measurement depending on current window setup

Some fine tuning of the above program segment can be carried out for example, by setting the trigger delay off. The following program segment assumes that channel A is currently being measured on the upper window .

ABOR1 CONF1 DEF,3 TRIG1:DEL:AUTO OFF READ1?

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Using INITiate and FETCh?

The following program segment assumes that channel A is currently being measured on the upper window.

ABOR1 Aborts channel A. CONF1 DEF,3 Configures the upper window to

make a measurement using the current setting of the expected power and source list and a resolution setting of 3.

INIT1 Causes channel A to make a

measurement.

FETC1? Retrieves the upper window’s

measurement.

Some fine tuning of the above program segment can be carried out for example, by setting the trigger delay off.

ABOR1 CONF1 DEF,3 TRIG1:DEL:AUTO OFF INIT1:IMM FETC1?

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Example 5 - Making a Difference Measurement

The following program segment can be carried out on the EPM-442A. It queries the lower window to make a difference measurement of channel A - channel B. The expected power level and resolution parameters are defaulted, leaving them at their current settings. Some fine tuning of the measurement is carried out by setting the averaging, and the trigger delay to off.

Using READ?

ABOR1 ABOR2 CONF2:POW:AC:DIFF DEF,DEF,(@1),(@2) SENS1:AVER:COUN 1024 SENS2:AVER:COUN 1024 TRIG1:DEL:AUTO OFF TRIG2:DEL:AUTO OFF READ2:POW:AC:DIFF?

READ?

READ2:POW:AC:DIFF? DEF,DEF,(@2),(@1)(A second

query is sent to make a channel B - channel A measurement using fresh measurement data.)

Using INITiate and FETCh?

ABOR1 ABOR2 CONF2:POW:AC:DIFF DEF,DEF,(@1),(@2) SENS1:AVER:COUN 1024 SENS2:AVER:COUN 1024 TRIG1:DEL:AUTO OFF TRIG2:DEL:AUTO OFF INIT1:IMM INIT2:IMM FETC2:POW:AC:DIFF? FETC2:POW:AC:DIFF? DEF,DEF,(@2),(@1) (A second FETCh? query is

sent to make a channel B - channel A measurement using the current measurement data.)

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Example 6 - Making a Ratio Measurement

The following program segment can be carried out on the EPM-442A. It queries the lower window t o make a rati o meas urement of c ha nnel A/B. The expected power level and resolution parame ters are defaulted, leaving them at their current settings. Some fine tuning of the measurement is carried out by setting the averaging.

Using READ?

ABOR1 ABOR2 CONF2:POW:AC:RAT DEF,DEF,(@1),(@2) SENS1:AVER:COUN 512 SENS2:AVER:COUN 256 READ2:POW:AC:RAT?

READ?

READ2:POW:AC:RAT? DEF,DEF,(@2),(@1) (A second

query is sent to make a channel B - channel A ratio measurement using fresh measurement data.)

Using INITiate and FETCh?

ABOR1 ABOR2 CONF2:POW:AC:RAT DEF,DEF,(@1),(@2) SENS1:AVER:COUN 512 SENS2:AVER:COUN 256 INIT1:IMM INIT2:IMM FETC2:POW:AC:RAT? FETC2:POW:AC:RAT? DEF,DEF,(@2),(@1) (A second FETCh? query is

sent to make a channel B - channel A measurement using the current measurement data.)

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Using the Lower Level Commands

An alternative method of making measurements is to use the lower level commands to set up the expected range and resolution. This can be done using the following commands:

[SENSe[1]]|SENSe2:POWER:AC:RANGe DISPlay[:WINDow[1|2]]:RESolution

The measurement type can be set using the following commands in the

CALCulate subsystem: CALCulate[1|2]:MATH[:EXPRession]

CALCulate[1|2]:RELative[:MAGNitude]

The advantage of using the lower level commands over the CONFigure command is that they give you more precise control of the power meter . As shown in Table 1-1 on page 1-8 the CONFigure command presets various states in the power meter. It may be likely that you do not want to preset these states.

Example

The following example sets the expected power value to -50 dBm and the resolution setting to 3 using the lower level commands. The measurement is a single channel A measurement carried out on the lower window.

ABOR1 Aborts channel A. CALC2:MATH:EXPR "(SENS1)" Displays channel A on lower

window.

SENS1:POW:AC:RANG 0 Sets lower range (E-series sensors

only).

DISP:WIND2:RES 3 Sets the lower window’s resolution

to setting 3.

INIT1 Causes channel A to make a

measurement.

FETC2? Retrieves the lower window’s

measurement.

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Making Measurements on Wireless Communication Standards

The following sections describe typical measurements you may want to

make. They are also described, for front panel operation, in the User’s Guide.

Measuring GSM

The following shows you how to measure the average power in a GSM RF burst. Triggering is achieved using the rising edge of the burst. The ‘useful’ part of the GSM burst lasts for 542.8µs with a rise time of 28µs. As the power meter triggers during the rising power transition, the measurement gate is configured to measure the average powe r in a 520µs period, 20 µs after triggering. The trigger is configured for the a power level of -20 dBm on a rising edge. A trigger hold off is also setup for 4275µs, disabling the trigger for 7.5 GSM time slots, ensuring the same time slot is measured at the next GSM frame . The single nume ric wind ow is configured to display the average power in gate 1. The trace window is configured to show the RF burst from 20µs ahead of the trigger for a duration of 700µs.

Note The E9321A and E9325A sensors are best suited as they have the

optimum dynamic range and low-level stability in the 300 kHz bandwidth.

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9321A|E9322A|E9323A| E9325A|E9326A|E9327A

The GSM setup is onl y valid with these sensors

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SENS:FREQ:900MHZ Sets the measurement

frequency to 900 MHz

SENS:BW:VID:HIGH Only send this command if

using an E9321A or E9325A

SENS:BW:VID:LOW Only send this command if

using an E9323A or E9327A

SENS:SWE1:OFFS:TIME:0.00002 Sets gate1 start point to

20µs after the trigger

SENS:SWE1:TIME0.00052 Sets gate1 length to 520µs INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger TRIG:LEV:AUTO OFF Turn off auto leveli n g for

trigger

TRIG:LEV -20.00DBM Sets trigger level to

-20.0 dBm

TRIG:DEL 0.00002 Actual trigger to occur 20µs

after trig level detected

TRIG:HOLD 0.004275 Sets trigger hold-off to

4.275 ms

DISP:WIND1:TRACE:LOW -35 Sets trace display minimum

power to -35 dBm

DISP:WIND1:TRACE:UPP 20 Sets trace display maximum

power to +20 dBm

SENS:TRAC:OFFS:TIME -0.00004 Trace starts 40µs before

trigger point

SENS:TRAC:TIME 0.0007 Trace span set to 700µs DISP:WIND1:FORM TRACE Assigns upper window to a

trace display

DISP:WIND2:FORM SNUM Assigns lower window to a

single numeric display

CALC2:FEED1 “POW:AVER ON SWEEP1” Lower window to show

average power using timing defined by gate1

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Measuring EDGE

Enhanced Data for Global Evolution or Enhanced Data for GSM Evolution is an enhancement of the GSM standard. The modulation scheme is 8PSK. As Edge does not have constant amplitude GMSK modulation like GSM, peak-to-average ratio may be of interest.

The following procedure shows you how to mea sure the average pow er in a GSM RF burst. Triggering is achieved using the rising edge of the burst.

The ‘useful’ part of the GSM burst lasts for 542.8µs with a rise time of 28µs. Also, trigger hysteresis is included to prevent small power transitions during the burst causing re-triggering. As the power meter triggers during the rising power transition, the measurement gate is configured to measure the average power in a 520µs period, 20 µs after triggering. The display is configured to show the peak and peak-to-average results in the lower window in numeric format while the upper window shows the power trace starting 40µs before the trigger.

Note The E9321A and E9325A sensors are best suited as they have the

optimum dynamic range and low-level stability in the 300 kHz bandwidth.

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9321A|E9322A|E9323A| E9325A|E9326A|E9327A

The EDGE setup is only valid with these sensors

SENS:FREQ:900MHZ Sets the measurement

frequency to 900 MHz

SENS:BW:VID:HIGH Only send this command if

using an E9321A or E9325A

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SENS:BW:VID:LOW Only send this command if

using an E9323A or E9327A

SENS:SWE1:OFFS:TIME:0.00002 Sets gate1 start point to

20µs after the trigger

SENS:SWE1:TIME0.00052 Sets gate1 length to 520µs INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger TRIG:LEV:AUTO OFF Turn off auto leveli n g for

trigger

TRIG:LEV -20.00DBM Sets trigger level to

-20.0 dBm

TRIG:DEL 0.00002 Actual trigger to occur 20µs

after trig level detected

TRIG:HOLD 0.004275 Sets trigger hold-off to

4.275 ms

TRIG:HYST 3.0 Sets Hysteresis to 3 dB DISP:WIND1:TRACE:LOW -55 Sets trace display minimum

power to -55 dBm

DISP:WIND1:TRACE:UPP 20 Sets trace display maximum

power to +20 dBm

SENS:TRAC:OFFS:TIME -0.00004 Trace starts 40µs before

trigger point

SENS:TRAC:TIME 0.0007 Trace span set to 700µs DISP:WIND1:FORM TRACE Assigns upper window to a

trace display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC2:FEED1 “POW:AVER ON SWEEP1” Lower window upper

display line to show average power using timing defined by gate1

CALC4:FEED1 “POW:PTAV ON SWEEP1” Lower window lower

display line to show peak-to-average ratio using timing defined by gate1

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Measuring NADC

The following procedure shows you how to measure the average power of

both active time slots in NADC or IS-136 ‘full rate’ transmission. This assumes that there are two time slots in each frame to be measured, for example, time slots 0.

IS-136 full rate frame

Triggering is achieved using the rising edge of the burst. The measurement gates ar e configured to measure the average power in two NADC time slots, separated by two inactive time slots. The rise time of an NADC TDMA burst is approximately 123.5µs (6bits) and the ‘useful’ part of the burst lasts approximately 6.4 ms. Gate 1 is configured to measure the average power in a 6.4ms period, 123.5 µs after triggering. Gate 2 is configured to measure the average power in a 6.4ms period, 20.123 ms (3 time slots plus rise times) after triggering.

The display is configured to show the Gate 1 and Gate 2 average results in the lower window in numeric format, while the upper window shows the power trace starting 2 ms before the trigger.

Note The narrow bandwidth of the NADC signal requires only the 30 kHz

bandwidth of the E9321A and E9325A sensors in the Low setting and these are best suited. Other E9320 sensors may be used in their lowest setting but they provide less dynamic range and low-level stability.

*CLS Clears error queue *RST Resets meter settings to their

:SYST:ERR? <read string> The system error query

1 2 0 1 2

default states

should return “0: No Error”

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SERV:SENS:TYPE? The sensor type query

should return one of the following: E9321A|E9322A|E9323A| E9325A|E9326A|E9327A

The NADC setup is only valid with these sensors

SENS:FREQ:800MHZ Sets the measurement

frequency to 800 MHz

SENS:BW:VID:LOW Select low video bandwidth SENS:SWE1:OFFS:TIME:0.0001235 Sets gate1 start point to

123.5µs after the trigger

SENS:SWE1:TIME0.0064 Sets gate1 length to 6.4 ms SENS:SWE2:OFFS:TIME:0.020123 Sets gate2 start point to

20.123 ms after the trigger

SENS:SWE2:TIME0.0064 Sets gate2 length to 6.4 ms INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger TRIG:LEV:AUTO OFF Turn off auto leveli n g for

trigger

TRIG:LEV -20.00DBM Sets trigger level to

-20.0 dBm

TRIG:HOLD 0.03 Sets trigger hold-off to

30 ms

DISP:WIND1:TRACE:LOW -35 Sets trace display minimum

power to -35 dBm

DISP:WIND1:TRACE:UPP 20 Sets trace display maximum

power to +20 dBm

SENS:TRAC:OFFS:TIME -0.0002 Trace starts 200µs before

trigger point

SENS:TRAC:TIME 0.028 Trace span set to 28 ms DISP:WIND1:FORM TRACE Assigns upper window to a

trace display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

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CALC2:FEED1 “POW:AVER ON SWEEP1” Lower window upper

display line to show average power using timing defined by gate1

CALC4:FEED1 “POW:PTAV ON SWEEP2” Lower window lower

display line to show peak-to-average ratio using timing defined by gate2

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Making Measurements on Wireless Communication Standards

Measuring iDEN

The following proced ure shows yo u how to meas ure the ave rage power, the peak-to-average powe r ra tio in o ne i DEN tra ining a nd data pu ls e , and the average power in a 90 ms iDEN frame. Triggering is achieved using the rising edge of the training burst. The trigger is configured for a power level of -30 dBm on a rising edge. Auto-level triggering may also be used. A trigger hold off is also set up to ensure the power meter is not re-triggered by the data pulse following the training pulse. Time gating is used to measure the average power in the following 15 ms pulse. The display is configured to show the peak-to-average ratio within the data pulse and the average power in the entire 90 ms frame on two display lines in the lower window while the upper window shows the average power in a 15 ms data pulse. All displays are numeric.

Note The narrow bandwidth of the iDEN signal requires only the 30 kHz

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9321A|E9322A|E9323A| E9325A|E9326A|E9327A

The iDEN setup is only valid with these sensors

SENS:FREQ:800MHZ Sets the measurement

frequency to 800 MHz

SENS:BW:VID:LOW Select low video bandwidth SENS:SWE1:OFFS:TIME:0.00001 Sets gate1 start point to

10 µs after the trigger

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SENS:SWE1:TIME0.015 Sets gate1 length to 15 ms SENS:SWE2:TIME0.090 Sets gate2 length to 90 ms INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger TRIG:LEV:AUTO OFF Turn off auto leveling for

trigger

TRIG:LEV -20.00DBM Sets trigger level to

-20.0 dBm

TRIG:HOLD 0.02 Sets trigger hold-off to

20 ms

DISP:WIND1:FORM SNUM Assigns upper window to a

single numeric display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC1:FEED1 “POW:AVER ON SWEEP1” Upper window to show

average power using timing defined by gate1

CALC2:FEED1 “POW:PTAV ON SWEEP1” Lower window upper

display line to show peak-to-average ratio using timing defined by gate1

CALC4:FEED1 “POW:PTAV ON SWEEP2” Lower window lower

display line to show peak power ratio using timing defined by gate2

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Measuring Bluetooth

The following procedure shows you how to measure the peak and average power in a single Bluetooth DH1 data burst. Triggering is achieved using the rising edge of the burst. The trigger is configured for a power level of

-20 dBm on a rising edge. A trigger hold off is also setup for 650µs, disabling the trigger until the current time slot is measured. The measurement gate is configured to measure the peak and average power in a 366µs period, 0.2µs after the trigger. The display is configured to show the peak and average power in the lower window in numeric format, while the upper window shows the power trace over 6 time slots starting 50µs before the trigger.

Note The E9321A and E9325A sensors are best suited. The E9321A and

E9325A are not recommended due to lack of bandwidth.

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9322A|E9323A| E9326A|E9327A

The Bluetooth setup is only valid with these sensors

SENS:FREQ:2400MHZ Sets the measurement

frequency to 2400 MHz

SENS:BW:VID:HIGH Only send this command if

using an E9322A or E9326A

SENS:SWE1:OFFS:TIME:0.0000002 Sets gate1 start point to

200 ns after the trigger

SENS:SWE1:TIME0.000366 Sets gate1 length to 366 µs INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger

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TRIG:LEV:AUTO OFF Turn off auto leveling for

trigger

TRIG:LEV -20.00DBM Sets trigger level to

-20.0 dBm

TRIG:HOLD 0.00065 Sets trigger hold-off to

4650µs

TRIG:HYST 3.0 Sets Hysteresis to 3 dB DISP:WIND1:TRACE:LOW -35 Sets trace display minimum

power to -35 dBm

DISP:WIND1:TRACE:UPP 20 Sets trace display maximum

power to +20 dBm

SENS:TRAC:OFFS:TIME -0.00001 Trace starts 10µs before

trigger point

SENS:TRAC:TIME 0.00065 Trace span set to 650µs DISP:WIND1:FORM TRACE Assigns upper window to a

trace display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC2:FEED1 “POW:AVER ON SWEEP1” Lower window upper

display line to show average power using timing defined by gate1

CALC4:FEED1 “POW:PEAK ON SWEEP1” Lower window lower

display line to show peak power using timing defined by gate1

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Measuring cdmaOne

The following procedure shows you how to make a continuous measurement on a cdmaOne signal. Peak an d peak-to-average power measurements are made over a defined and statistically valid number of samples. With gated 10 ms measurements, corresponding to 200,000 samples, there is less than a 0.01% probability that there are no peaks above the measured peak value. The trigger is configured for continuous triggering on a rising edge at -10 dBm. This results in continuously updated results based on a 10 ms period relating to a position beyond

0.01% on the CCDF curve, responding to any changes in signal or DUT.

Note The E9322A and E9326A sensors are best suited due to their 1.5 MHz

bandwidth. The E9321A and E9325A are not recommended due to their lack of bandwidth.

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9322A|E9323A| E9326A|E9327A

The cdmaOne setup is only valid with these sensors

SENS:FREQ:850MHZ Sets the measurement

frequency to 850 MHz

SENS:BW:VID:HIGH Only send this command if

using an E9322A or an E9326A

SENS:SWE1:OFFS:TIME:0 Sets gate1 start point to the

trigger point

SENS:SWE1:TIME 10E-3 Sets gate time to 10 ms INIT:CONT ON Puts meter in “wait for

trigger” state

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TRIG:SOUR INT Selects internal trigger TRIG:LEV:AUTO OFF Turn off auto leveling for

trigger

TRIG:LEV -10.00DBM Sets trigger level to

-10.0 dBm

DISP:WIND1:FORM SNUM Assigns upper window to a

single numeric display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC1:FEED1 “POW:AVER” Upper window to show

average power

CALC2:FEED1 “POW:PEAK” Lower window upper

display line to show peak power

CALC4:FEED1 “POW:PTAV” Lower window lower

display line to show peak-to-average ratio

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Measuring W-CDMA

The following procedure shows you how to make a continuous measurement on a W-CDMA signal. Peak and peak-to-average power measurements are made over a defined and statistically valid number of samples. With gated 10 ms measurements, corresponding to 200,000 samples, there is less than a 0.01% probability that there are no peaks above the measured peak value.The trigger is configured for continuous triggering on a rising edge at -10 dBm. This results in continuously updated results based on a 10 ms period relating to a position beyond

0.01% on the CCDF curve, responding to any changes in signal or DUT.

Note The E9323A and E9327A sensors are best suited due to their 5 MHz

bandwidth. The E9321A, E9322A, E9325A, and E9326A sensors are not recommended due to their lack of bandwidth (5 MHz required).

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9323A| E9327A

The W-CDMA setup is only valid with these sensors

SENS:FREQ:1900MHZ Sets the measurement

frequency to 1900 MHz

SENS:BW:VID:HIGH Sets the sensor bandwidth

to high

SENS:SWE1:OFFS:TIME:0 Sets gate1 start point to the

trigger point

SENS:SWE1:TIME 10E-3 Sets gate time to 10 ms INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger

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TRIG:LEV:AUTO OFF Turn off auto leveling for

trigger

TRIG:LEV -10.00DBM Sets trigger level to

-10.0 dBm

DISP:WIND1:FORM SNUM Assigns upper window to a

single numeric display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC1:FEED1 “POW:AVER” Upper window to show

average power

CALC2:FEED1 “POW:PEAK” Lower window upper

display line to show peak power

CALC4:FEED1 “POW:PTAV” Lower window lower

display line to show peak-to-average ratio

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Measuring cdma2000

The following procedure shows you how to make a continuous measurement on a cdma2000 signal. Peak and peak-to-average power measurements are made over a defined and statistically valid number of samples. With gated 10 ms measurements, corresponding to 200,000 samples, there is less than a 0.01% probability that there are no peaks above the measured peak value. The trigger is configured for continuous triggering on a rising edge at -10 dBm. This results in continuously updated results based on a 10 ms period relating to a position beyond

0.01% on the CCDF curve, responding to any changes in signal or DUT.

Note The E9323A and E9327A sensors are best suited due to their 5 MHz

bandwidth. The E9321A, E9322A, E9325A, and E9326A sensors are not recommended due to their lack of bandwidth (5 MHz required).

*CLS Clears error queue *RST Resets meter settings to their

default states

:SYST:ERR? <read string> The system error query

should return “0: No Error”

SERV:SENS:TYPE? The sensor type query

should return one of the following: E9323A| E9327A

The cdma2000 setup is only valid with these sensors

SENS:FREQ:1900MHZ Sets the measurement

frequency to 1900 MHz

SENS:BW:VID:HIGH Sets the sensor bandwidth

to high

SENS:SWE1:OFFS:TIME:0E-6 Sets gate1 start point to the

trigger point

SENS:SWE1:TIME 10E-3 Sets gate time to 10 ms INIT:CONT ON Puts meter in “wait for

trigger” state

TRIG:SOUR INT Selects internal trigger

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TRIG:LEV:AUTO OFF Turn off auto leveling for

trigger

TRIG:LEV -10.00DBM Sets trigger level to

-10.0 dBm

DISP:WIND1:FORM SNUM Assigns upper window to a

single numeric display

DISP:WIND2:FORM DNUM Assigns lower window to a

dual numeric display

CALC1:FEED1 “POW:AVER” Upper window to show

average power

CALC2:FEED1 “POW:PEAK” Lower window upper

display line to show peak power

CALC4:FEED1 “POW:PTAV” Lower window lower

display line to show peak-to-average ratio

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Using Sensor Calibration Tables

This section applies to all 8480 series power sensors. It does not apply to the E-series power sensors. All E-series power sensors have their sensor calibration tables stored in EEPROM which allows frequency and calibration factor data to be downloaded by the power meter automatically.

This section describes how to use sensor calibration tables. Sensor calibration tables are used to store the measurement calibration factors, supplied with each power sensor, in the power meter. These calibration factors are used to correct measurement results.

Overview

For the 8480 series power sensors there are two methods of providing correction data to the power meter depending on the setting of the

[SENSe[1]]|SENSe2:CORRection:CSET1:STATe command. If [SENSe[1]]|SENSe2:CORRection:CSET1:STATe is OFF the sensor

calibration tables are not used. To make a calibrated power measurement when [SENSe[1]]|SENSe2:CORRection:CSET1:STATe is OFF, perform the following steps:

1. Zero and calibrate the power meter. Before carrying out the calibration set the reference calibration factor for the power meter you are using.

2. Set the calibration factor to the value for the frequency of the signal you want to measure.

3. Make the measurement.

When [SENSe[1]]|SENSe2:CORRection:CSET1:STATe is ON, the sensor calibration tables are used, providing you with a quick and convenient method for making power measurements at a range of frequencies using one or more power sensors. Note that with the sensor calibration table selected, the RCF from the table overrides any value previously set. The power meter is capable of storing 20 sensor calibration tables of 80 frequency points each.

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Figure 1-1 illustrates how sensor calibration tables operate.

Figure 1-1: Sensor Calibration Tables

TABLE 1

RCF

FREQ

CFAC = Calibration Factor

RCF = Reference Calibration Factor

Frequency of the signal you want to measure

CFAC

2 . .

. . . . . . . . .

CFAC

2 . .

. . . . . . . . .

CFAC

TABLE N

FREQ

2 . .

. . . . . . . . .

FREQ

TABLE SELECTED

FREQ

2 . .

. . . . . . . . .

FREQ

RCF CFAC

CFAC

2 . .

. . . . . . . . .

CFAC

RCF

CFAC

2 . .

. . . . . . . . .

CFAC

TABL E 20

RCF

FREQ

CFAC

2 . .

. . . . . . . . .

Reference Calibration Factor used for Power Meter Calibration.

Calibration Factor used to make Measu re me n t . Calculated by the Power Meter using linear interpolation

CFAC

2 . .

. . . . . . . . .

CFAC

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To use sensor calibration tables you:

1. Edit a sensor calibration table if necessary.

2. Select the sensor calibration table.

3. Enable the sensor calibration table.

4. Zero and calibrate the power meter. The reference calibration factor used during the calibration is automatically set by the power meter from the sensor calibration table.

5. Specify the frequency of the signal you want to measure. The calibration factor is automatically set by the power meter from the sensor calibration table.

6. Make the measurement.

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Editing Sensor Calibration Tables

It is not possible to create any additional sensor calibration tables. However, the 20 existing ones can be edited using the MEMory subsystem. To do this:

1. Select one of the existing tables using: MEMory:TABle:SELect <string>.

For information on naming sensor calibration tables see “Naming Sensor Calibration Tables”, on page 1-47. For information on the current names which you can select refer to “Listing Sensor Calibration Table Names”, on page 1-45.

2. Enter the frequency data using:

MEMory:TABle:FREQuency <numeric_value> {,<numeric_value>}

3. Enter the calibration factors using:

MEMory:TABle:GAIN <numeric_value> {,<numeric_value>}. The first parameter you enter should be

the reference calibration factor, each subsequent parameter is a calibration factor in the sensor calibration table. This means that entries in the frequency list correspond as shown with entries in the calibration factor list.

Frequency Calibration Factor

Reference Calibration

Factor Frequency 1 Calibration Factor 1 Frequency 2 Calibration Factor 2

Frequency n Calibration Factor n

4. If required, rename the sensor calibration table using: MEMory:TABLe:MOVE <string>,<string>. The first <string> parameter identifies the existing table name, and the second identifies the new table name.

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Note The legal frequency suffix multipliers are any of the IEEE suffix

multipliers, for example, KHZ, MHZ and GHZ. If no units are specified the power meter assumes the data is Hz.

PCT is the only legal unit for calibration factors and can be omitted. The frequency and calibration data must be within range. Refer to the

individual commands in Chapter 4 for their specified ranges. The number of calibration factor points must be one more than the

number of frequency points. This is verified when the sensor calibration table is selected using

[SENSe[1]]|SENSe2:CORRection:CSET1[:SELect] <string>

Ensure that the frequency points you use cover the frequency range of the signals you want to measure. If you measure a signal with a frequency outside the frequency range defined in the sensor calibration table, then the power meter uses the highest or lowest frequency point in the sensor calibration table to calculate the calibration factor.

To make subsequent editing of a sensor calibration table simpler, it is recommended that you retain a copy of your data in a program.

Listing Sensor Calibration Table Names

To list the tables currently stored in the power meter, use the following command:

MEMory:CATalog:TABLe?

Note that all tables are listed, including frequency dependent offset tables.

The power meter returns the data in the form of two numeric parameters and a string list representing all the stored tables.

• <numeric_value>,<numeric_value>{,<string>}

The first numeric parameter indicates the amount of memory, in bytes, used for storage of tables. The second parameter indicates the memory, in bytes, available for tables.

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Each string parameter returned indicates the name, type and size of a stored sensor calibration table:

• <string>,<type>,<size> The <string>, <type> and <size> are all character data. The <type> is always TABL. The <size> is displayed in bytes.

For example, a sample of the response may look like:

560,8020,“Sensor_1,TABL,220”,”Sensor_2,TABL,340” ....

The power meter is shipped with a set of predefined sensor calibration tables. The data in these sensor calibration tables is based on statistical averages for a range of Agi lent Technologies power sensors. These power sensors are:

•DEFAULT

• 8481A

• 8482A

• 8483A

• 8481D

• 8485A

• R8486A

• Q8486A

• R8486D

• 8487A

For further information on naming sensor calibration tables see “Naming Sensor Calibration Tables”, on page 1-47.

1. DEFAULT is a sensor calibration table in which the reference calibration

factor and calibration factors are 100%. This sensor calibration table can be used during the performance testing of the power meter.

2. The 8482B and 8482H power sensors use the same data as the 8482A.

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Naming Sensor Calibration Tables

To rename a sensor calibration table use:

MEMory:TABLe:MOVE <string>,<string>

The first <string> parameter identifies the existing table name, and the second identifies the new table name.

The following rules apply to sensor calibration table names:

a) The sensor calibration table must consist of no more than 12

characters.

b) All characters must be upper or lower case alphabetic characters,

or numeric (0-9), or an underscore (_).

c) No spaces are allowed in the name.

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Reviewing Table Data

To review the data stored in a sensor calibration table, use the following commands:

• MEMory:TABLe:SELect "Sense1"

Select the sensor calibration table named “Sense1”.

• MEMory:TABLe:SELect?

Query command which returns the name of the currently selected table.

• MEMory:TABLe:FREQuency:POINTs?

Query command which returns the number of stored frequency points.

• MEMory:TABLe:FREQuency?

Query command which returns the frequencies stored in the sensor calibration table (in Hz).

• MEMory:TABLe:GAIN[:MAGNitude]:POINTs?

Query command which returns the number of calibration factor points stored in the sensor calibration table.

• MEMory:TABLe:GAIN[:MAGNitude]?

Query command which returns the calibration factors stored in the sensor calibration table. The first point returned is the reference calibration factor.

Modifying Data

If you need to modify the frequency and calibration factor data stored in a sensor calibration table you need to resend the complete data lists. There are two ways to do this:

1. If you have retained the original data in a program, edit the program and resend the data.

2. Use the query commands shown in “Reviewing Table Data”, on page 1-48 to enter the data into your computer. Edit this data, then resend it.

Selecting a Sensor Calibration Table

After you have created the sensor calibration table, you can select it using the following command:

[SENSe[1]]|SENSe2:CORRection:CSET1[:SELect] <string>

When the table is selected, the power meter verifies the number of calibration factor points defined in the sensor calibration table is one

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Using Sensor Calibration Tables

parameter greater than the number of frequency points. If this is not the case an error occurs.

To find out which sensor calibration table is currently selected, use the query:

[SENSe[1]]|SENSe2:CORRection:CSET1[:SELect]?

Enabling the Sensor Calibration Table System

To enable the sensor calibration table, use the following command:

[SENSe[1]]|SENSe2:CORRection:CSET1:STATe ON If you set [SENSe[1]]|SENSe2:CORRection:CSET1:STATe to ON and

no sensor calibration table is selected error -221, “Settings conflict” occurs .

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Making the Measurement

To make the power me asurement, se t the power me ter for the f requency of the signal you want to measure . The power meter automatically sets the calibration factor. Use either the INITiate,FETCh? or the READ? query to initiate the measurement as shown in the following program segments:

INITiate Example

ABORt1 CONFigure1:POWer:AC DEF,1,(@1) SENS1:CORR:CSET1:SEL "HP8481A" SENS1:CORR:CSET1:STAT ON SENSe1:FREQuency 500KHZ INITiate1:IMMediate FETCh1?

READ? Example

ABORt1 CONFigure1:POWer:AC DEF,2,(@1) SENS1:CORR:CSET1:SEL "HP8481A" SENS1:CORR:CSET1:STAT ON SENSe1:FREQuency 500KHZ READ1?

Note If the measurement frequency does not correspond directly to a

frequency in the sensor calibration table, the power meter calculates the calibration factor using linear interpolation.

If you enter a frequency outside the frequency range defined in the sensor calibration table, then the power meter uses the highest or lowest frequency point in the sensor calibration table to set the calibration factor.

To find out the value of the calibration factor being used by the power meter to make a measurement, use the query command: [SENSe[1]]|SENSe2:CORRection:CFAC? The response may be an interpolated value.

To find out the value of the reference ca libration fa ctor being use d, use the commands:

CALibration[1|2]:RCFactor?

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Using Frequency Dependent Offset Tables

This section describes how to use frequency dependent offset tables. Frequency dependent offset tables give you the ability to compensate for frequency effects in your test setup.

Overview

If the [SENSe[1]]|SENSe2:CORRection:CSET2:STATe command is OFF, the frequency dependent offset tables are not used. When [SENSe[1]]|SENSe2:CORRection:CSET2:STATe is ON, the frequency

dependent offset tables are used, providing you with a quick and convenient method of compensating for your external test setup over a range of frequencies. Note that when selected, freque ncy dependent offset correction is IN ADDITION to any correction applied for sensor freque ncy response. The power meter is capable of storing 10 frequency dependent offset tables of 8 0 frequency points each.

To u se frequency dependent offset tables you:

1. Edit a freq uency depend ent offset tab le if necessary.

2. Select the frequency dependent offset table.

3. Enabl e the freque ncy dep ende nt offs et table.

4. Zero and calibrate the power meter. The reference calibration factor used during the calibration will be automatically set by the power meter from a sensor calibration table, if enabled; otherwise it should be entered manually.

5. Specify the frequency of the signal you want to measure. The required offset is automatically set by the power meter from the frequency dependent offset ta ble.

6. Make the measurement.

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Figure 1-2 illustrates how frequency dependent offset tables operate.

Figure 1-2: Frequency Dependent Offset Tables

TABLE 1

FREQ

OFFSET

FREQ

OFFSET 2 . .

. . . . . . . . .

FREQ

OFFSET = Frequency Dependent Offset

Frequency of the signal you want to measure

2 . .

. . . . . . . . .

OFFSET

TABLE SELECTED

TABLE N

FREQ

2 . .

. . . . . . . . .

FREQ

OFFSET

2 . .

. . . . . . . . .

OFFSET

. .

. . . . . . . . .

OFFSET

. .

. . . . . . . . .

OFFSET

TABL E 10

FREQ

OFFSET

FREQ

Frequency dependent offset used to make Measurement. Calculated by the Power Meter using linear interpolation.

2 . .

. . . . . . . . .

. .

. . . . . . . . .

OFFSET

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Editing Frequency Dependent Offset Tables

It is not possible to create any additional frequency dependent offset tables. However, the 10 existing ones can be edited using the MEMory subsystem. To do this:

1. Select one of the existing tables using: MEMory:TABle:SELect <string>. For information on naming frequency dependent offset tables see

“Naming Frequency Dependent Offset Tables”, on page 1-55. For information on the current names which you can select refer to “Listing the Frequency Dependent Offset Table Names”, on page 1-54.

2. Enter the frequency data using:

MEMory:TABle:FREQuency <numeric_value> {,<numeric_value>}

3. Enter the offset factors as shown in the table below using:

MEMory:TABle:GAIN <numeric_value> {,<numeric_value>}

Frequency Offset

Frequency 1 Offset 1 Frequency 2 Offset 2

Frequency n Offset n

4. If required, rename the frequency dependent offset table using: MEMory:TABLe:MOVE <string>,<string>. The first <string> parameter identifies the existing table name, and the second identifies the new table name.

Note The legal frequency suffix multipliers are any of the IEEE suffix

multipliers, for example, KHZ, MHZ and GHZ. If no units are specified the power meter assumes the data is Hz.

PCT is the only legal unit for offset factors and can be omitted. The frequency and offset data must be within range. Refer to the

individual commands in Chapter 4 for their specified ranges.

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Any offset values ente red into the table sho uld exclude th e effect of the sensor. Characterization of the test setup independently of the sensor allows the same table to be used with any sensor.

Ensure that the frequency points you use cover the freque ncy range of the signals you want to measure. If you measure a signal with a frequency outside the frequency range defined in the frequency dependent offset table, then the power meter uses the highest or lowest frequency point in the table to calculate the offset.

To make subsequent editing of a frequency dependent offset table simpler, it is recommended that you retain a copy of your data in a program.

Listing the Frequency Dependent Offset Table Names

To li st the f req uency de pend ent o ffs et t a bles cu rrent ly s to red in the po wer meter, use the following command:

MEMory:CATalog:TABLe?

Note that all tables are listed; including sensor calibration tables. The power meter returns the data in the form of two numeric parameters

and a string list representing all stored tables.

• <numeric_value>,<numeric_value>{,<string>} The first numeric parameter indicates the amount of memory, in bytes, used for storage of tables. The second parameter indicates the memory, in bytes, available for tables.

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Using Frequency Dependent Offset Tables

Each string parameter returned indicates the name, type and size of a stored frequency dependent offset table:

• <string>,<type>,<size> The <string>, <type> and <size> are all character data. The <type> is always TABL. The <size> is displayed in bytes.

For example, a sample of the response may look like:

560,8020,“Offset_1,TABL,220”,”Offset_2,TABL,340” ....

Naming Frequency Dependent Offset Tables

To rename a fr equency dependent offset table use:

MEMory:TABLe:MOVE <string>,<string>

The first <string> parameter identifies the existing table name, and the second identifies the new table name.

The following rules apply to frequency dependent offset table names:

a) Table names use a maximum of 12 characters. b) All characters must be upper or lower case alphabetic characters,

or numeric (0-9), or an underscore (_).

c) No spaces are allowed in the name.

Reviewing Table Data

To review the data stored in a frequency dependent offset table, use the following commands:

• MEMory:TABLe:SELect "Offset1"

Select the sensor calibration table named “Offset1”.

• MEMory:TABLe:SELect?

Query command which returns the name of the currently selected table.

• MEMory:TABLe:FREQuency:POINTs?

Query command which returns the number of stored frequency points.

• MEMory:TABLe:FREQuency?

Query command which returns the frequencies stored in the frequency dependent offset table (in Hz).

• MEMory:TABLe:GAIN[:MAGNitude]:POINTs?

Query command which returns the number of offset factor points stored in the frequency dependent offset table.

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Using Frequency Dependent Offset Tables

• MEMory:TABLe:GAIN[:MAGNitude]?

Query command which returns the offset factors stored in the frequency dependent offset table.

Modifying Data

If you need to modify the frequency and offset factor data stored in a frequency dependent offset tab le you need to resend t he complete data lis ts. There are two ways to do this:

1. If you have retained the original data in a program, edit the program and resend the data.

2. Use the query commands shown in “Reviewing Table Data”, on page 1-48 to enter the data into your computer. Edit this data, then resend it.

Selecting a Frequency Dependent Offset Table

After you have created the frequency dependent offset table, you can select it using the following command:

[SENSe[1]]|SENSe2:CORRection:CSET2[:SELect] <string>

To find out which frequency dependent offset table is currently selected, use the query:

[SENSe[1]]|SENSe2:CORRection:CSET2[:SELect]?

Enabling A Frequency Dependent Offset Table

To enable the freque ncy dep endent offse t table , use th e following command :

[SENSe[1]]|SENSe2:CORRection:CSET2:STATe ON

If you set [SENSe[1]]|SENSe2:CORRection:CSET2:STATe to ON and no frequency dependent offset table is selected error -221, “Settings conflict” occurs.

Making The Measurement

To make the power measurement, set the power meter for the frequency of the signal you want to measure. The power meter automatically sets the

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Using Frequency Dependent Offset Tables

calibration factor. Use either the INITiate,FETCh? or the READ? query to initiate the measurement as shown in the following program segments:

INITiate Example

ABORt1 CONFigure1:POWer:AC DEF,1,(@1) SENS1:CORR:CSET2:SEL "Offset1" SENS1:CORR:CSET2:STAT ON SENSe1:FREQuency 500KHZ INITiate1:IMMediate FETCh1?

READ? Example

ABORt1 CONFigure1:POWer:AC DEF,2,(@1) SENS1:CORR:CSET2:SEL "Offset1" SENS1:CORR:CSET2:STAT ON SENSe1:FREQuency 500KHZ READ1?

Note If the measurement frequency does not correspond directly to a

frequency in the frequency dependent offset table, the power meter calculates the offset using linear interpolation.

If you enter a frequency outside the frequency range defined in the frequency dependent offset ta ble, then the power meter uses the highest or lowest frequency point in the table to set the offset.

To find out the value of the offset being used by the power meter to make a measurement, use the query command: SENSe:CORRection:GAIN4|FDOFfset[:INPut][MAGNITUDE]? The response may be an interpolated value.

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Power Meter Remote Operation

Setting the Range, Resolution and Averaging

This section provides an overview of setting the range, resolution and averaging. F or more detailed information about these features refer to the individual commands in Chapter 9.

Range

The power meter has no internal ranges which can be set. The only ranges that can be set are those of the E-series power sensors. With an E-series power sensor the range can be set either automatically or manually. Use autoranging when you are not sure of the power level you will be measuring.

Setting the Range

To set the rang e manually us e the following command:

[SENSe[1]]|SENSe2:POWer:AC:RANGe <numeric_value> If the <numeric_value> is set to:

• 0, the sensor’s lower range is selected. (For example, this range is -70 to

-13.5 dBm for the E4412A power sensor.)

• 1, the sensor’s upper range is selected. (For example, this range is -14.5 to +20 dBm for the E4412A power sensor.)

For details on the range limits of other E-se ries power se nso rs refer to the appropriate power sensor manual.

For further information on this command refer to page 9-47. To enable autoranging use the following command:

[SENSe[1]]|SENSe2:POWer:AC:RANGe:AUTO ON

Use autoranging when you are not sure of the power level you will be measuring.

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Setting the Range, Resolution and Averaging

Resolution

You can set the window’s resolution using the following command:

DISPlay[:WINDow[1]|2][:NUMeric[1]|2] :RESolution <numeric_value>

There are four levels of resolution available (1 through 4). When the measurement suffix is W or % this parameter represents the

number of significant digits. When the measurement suffix is dB or dBM, 1 through 4 represents 1, 0.1, 0.01, and 0.001 dB respectively.

For further inf ormation refe r to the :RESolution command on page 5-21.

Averaging

The power meter has a digital filter to average power readings. The number of readings averaged can range from 1 to 1024. This filter is used to reduce noise, obtain the desired resolution and to reduce the jitter in the measurement results. However, the time to take the measurement is increased. You can select the filter length or you can set the power meter to auto filter mode. To enable and disable averaging use the following command:

[SENSe[1]]|SENSe2:AVERage[:STATe] <boolean>

Auto Averaging Mode

To enable and disable auto filter mode, use the following command:

[SENSe[1]]|SENSe2:AVERage:COUNt:AUTO <boolean>

When the auto filter mode is enabled, the power meter automatically sets the number of readings averaged together to satisfy the filtering requirements for most power measurements. The number of readings averaged together depends on the re solution and the po wer level currently being measured. Figure 1-3 lists the number of readings averaged for each range and resolution when the power meter is in auto filter mode.

Note Figure 1-3 applies to 8480 series sensors only.

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Setting the Range, Resolution and Averaging

Figure 1-3: Averaged Readings

Minimum Sensor Power

10 dB

Dynamic Range

10 dB

Power Sensor

1234 8 8 128 128

1 1 16 256

11232

11116

1118

Maximum Sensor Power

Figure 1-4 illustrates part of the power sensor dynamic range hysteresis.

Figure 1-4: Averaging Range Hysteresis

Range Hysteresis

Resolution Setting

Number of Averages

10.5 dB9.5 dB

Minimum Sensor Power Minimum Sensor Power + 10 dB

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Setting the Range, Resolution and Averaging

Filter Length

You specify the filter length using the following command:

[SENSe[1]]|SENSe2:AVERage:COUNt <numeric_value>

The range of values for the filter length is 1 to 1024. Specifying this command disables automatic filter length selection. Increasing the value of the filter length reduces measurement noise. However, the time to take the measurement is increased.

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Power Meter Remote Operation

Setting Offsets

Channel Offsets

The power meter can be configured to compensate for signal los s or gain in your test setup (for example, to compensate for the loss of a 10 dB attenuator). You use the SENSe command subsystem to configure the power meter. Gain and loss correction are a coupled system. This means that a gain set by [SENSe[1]]|SENSe2:CORRection:GAIN2 is represented in the [SENSe[1]]|SENSe2:CORRection:LOSS2? command. If you enter an offset value the state is automatically enabled. However it can be enabled and disabled using either the

[SENSe[1]]|SENSe2:CORRection:GAIN2:STATe or [SENSe[1]]|SENSe2:CORRection:LOSS2:STATe commands.

LOSS2 is coupled to GAIN2 by the equation when the default

Loss

-------------=

Gain

unit is linear, and when the default is logarithmic.

Note You can only use LOSS2 and GAIN2 for external losses and gains.

LOSS1 and GAIN1 are specifically for calibration factors.

Gain Loss–=

Display Offsets

Display offset values can be entered using the

CALCulate[1|2]:GAIN[:MAGNitude] command. CALCulate[1|2]:GAIN:STATe must be set to ON to enable the offset

value. If you enter an offset value the state is automatically enabled. On the EPM-442A this offset is applied after any math calculations (refer to Figure1-8 on page 1-75).

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Setting Offsets

Example

The following example program, in HP Basic, details how to use the channel and display offsets on an E4417A making a channel A/B ratio measurement. The final result will be:



------------------------- --



dBm dBm

10–

20–

10–

10 !Create I/O path name 20 ASSIGN @POWER TO 713 30 !Clear the power meter’s interface

40 CLEAR @POWER 50 !Set the power meter to a known state 60 OUTPUT @POWER;"*RST" 70 !Configure the Power Meter to make the measurement 80 OUTPUT @Power;"CONF:POW:AC:RAT 20DBM,2,(@1),(@2)" 90 !Set the measurement units to dBm 100 OUTPUT @POWER;"UNIT:POW DBM" 110 !Set the power meter for channel offsets of -10 dB 120 OUTPUT @POWER;"SENS1:CORR:GAIN2 -10" 130 OUTPUT @POWER;"SENS2:CORR:GAIN2 -10" 140 !Enable the gain correction 150 OUTPUT @POWER;"SENS:CORR:GAIN2:STATe ON" 160 OUTPUT @POWER;"SENS2:CORR:GAIN2:STATe ON" 170 !Set the power meter for a display offset of -20 dB 180 OUTPUT @POWER;"CALC1:GAIN -20 DB" 190 PRINT "MAKING THE MEASUREMENT" 200 !Initiate the measurement 210 OUTPUT @Power;"INIT1:IMM" 220 OUTPUT @Power;"INIT2:IMM" 230 ! ... and get the result 240 OUTPUT @Power;"FETC:POW:AC:RAT? 20DBM,2,(@1),(@2)" 250 ENTER @Power;Reading 260 ! 270 PRINT "The measurement result is ";Reading;"dB." 280 END

For further information on channel offsets refer to page 9-35. For further information on display offsets refer to page 3-7.

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Power Meter Remote Operation

Setting Measurement Limits

You can configure the power meter to detect when a measurement is outside of a predefined upper and/or lower limit value.

Limits are window or measurement display line based and can be applied to power, ratio or difference measurements. In addition, the limits can be set to output a TTL logic level at the rear panel Rmt I/O port when the predefined limits are exceeded.

Setting Li mi ts

The power meter can be configured to verify the power being measured against an upper and/or lower limit value. The range of values that can be set for lower and upper limits is -150.00 dBm to +230.00 dBm. The default upper limit is +90.00 dBm and the default lower limit is -90.00 dBm.

A typical application for this feature is shown in Figure 1-5.

Figure 1-5: Limits Checking Application

Power Meter

Swept Source

Device Under T est

OUT

CHANNEL A INPUT

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Amplitude

Pow er Meter Remote Operatio n

Setting Measurement Limits

Figure 1-6: Limits Checking Results

+10 dBm

4 dBm

Fail o

o Fail

Frequency

Setting Limits

The power meter can be configured to verify the current measurement in any measurement line against predefined upper and/or lower limit values. The range of values that can be set for the upper and lower limits and the default values depends on the measurement units in the currently measurement line - see Table 1-2.

Table 1-2: Range of Values for Window Limits

Window

Units

Max Min

Default

Max Min

dB +200 dB -180 dB 60 dB -120 dB

dBm +230 dBm -150 dBm 90 dBm -90 dBm

% 999.9 X% 100.0 a% 100.0 M% 100.0 p%

W 100.000 XW 1.000 aW 1.000 MW 1.000 pW

The limits can also be set to output a TTL logic level at the rear panel Rmt I/O port when the predefined limits are exceeded. You can switch the rear panel TTL outputs on or off; set the TTL output level to active high or low; and determine whether the TTL output represents an over limit condition,

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Setting Measurement Limits

under limit condition or both. Refer to Chapter 8 “OUTput Subsystem” for TTL output programming commands and to the EPM-P Series Power Meters User’s Guide for connector and pin-out information.

Checking for Li mit Failures

There are two ways to check for limit failures:

1. Use the SENSe:LIMit:FAIL? and SENSe:LIMit:FCOunt? commands for channel limits or the

CALCulate[1|2]:LIMit:FAIL? and the CALCulate[1|2]:LIMit:FCOunt? for window limits.

2. Use the STATus command subsystem.

Using SENSe and CALCulate

Using SENSe to check the channel limit failures in Figure 1-6 would return the following results:

SENSe:LIMit:FAIL? Returns 1 if there has been 1 or

more limit failures or 0 if there have been no limit failures. In this case 1 is returned.

SENSe:LIMit:FCOunt? Returns the total number of

limit failures, in this case 2.

Use the equivalent CALCulate commands for checking window limit failures.

Note If TRIGger:DELay:AUTO is set to ON, then the number of failures

returned by SENSe:LIMit:FCOunt? or CALCulate[1|2]:LIMit:FCOunt?will be affected by the current filter settings.

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Setting Measurement Limits

Using STATus

You can use the STATus subsystem to generate an SRQ to interrupt your program when a limit failure occurs. This is a more efficient method than using SENSe or CALCulate, since you do not need to check the limit failures after every power measurement.

Refer to “Status Reporting”, on page 1-76 and “STATus Subsystem”, on page 10-1 for further information.

Configuring the TTL Outputs

The TTL Outputs on the rear pane l Rmt I/O port can be used to de termine when a predefined limit in either, or both, windows has been exceeded.

Example

The following program segm ent shows how to use TTL ou tput 1 to indicate when a measurement is outside the range -30 dBm to -10 dBm. It is assumed that the measurement has already been set up in the upper window (window 1).

CALC1:LIM:LOW -30 Sets the lower limit for the upper

window to -30 dBm.

CALC1:LIM:UPP -10 Sets the upper limit for the

upper window to -10 dBm.

CALC1:LIM:STAT ON Turns the limits on. OUTP:TTL1:FEED

“CALC1:LIM:LOW,CALC1:LIM:UPP”

OUTP:TTL1:ACT HIGH Specifies that TTL output 1

OUTP:TTL1:STAT ON Activates TTL output 1

EPM-P Series Power Meters Programming Guide 1-67

Specifies that TTL output 1 should be asserted when the upper or lower limit fails on the upper window.

should be act ive-high.

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Power Meter Remote Operation

Measuring Pulsed Signals

Note The E-series E9320 power sensors are best suited for peak and pulse

power measurement However, the E-series E9300 or 8480 series power sensors can be used. Pulse measurements are not recommended using E-series E4410 power sensors.

Using Duty Cycle

The following method describes pulse measurement without the use of an E-series E9320 power sensor. The measurement result is a mathematical representation of the pulse power rather than an actual measurement. The power meter measures the average power of the pulsed input signal and then divides th e measureme nt resul t by t he duty cycle value to obtai n the pulse power reading. The allowable range of values is 0.001% to

99.999%. The default is 1.000%. A duty cycle value can be set using the following command:

[SENSe[1]]|SENSe2:CORRection:DCYCle|GAIN3 <numeric_value>

Making the Measurement

An example of a pulsed signal is shown in Figure 1-7.

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Pow er Meter Remote Operatio n

Power

Figure 1-7: Pulsed Signal

Measuring Pulsed Signals

Duty Cycle = A

Duty Cycle (%) = A x 100

Time

You use the SENSe command subsystem to configure the power meter to measure a pulsed signal. The following example program, in HP Basic, shows how to measure the signal for the 8480 series power sensors.

Note Pulse power averages out any aberrations in the pulse such as

overshooting or ringing. For this reason it is called pulse power and not peak power or peak pulse power.

In order to ensure accurate pulse power readings, the input signal must be pulsed with a rectangular pulse. Other pulse shapes (such as triangle, chirp or Gaussian) will cause erroneous results.

The pulse power on/off rati o must be much g reater tha n the duty cyc le ratio.

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Power Meter Remote Operation

Measuring Pulsed Signals

10 !Create I/O path name 20 ASSIGN @Power TO 713

30 !Clear the Power Meter’s Interface 40 CLEAR @Power 50 !Set the Power Meter to a known state 60 OUTPUT @Power;"*RST" 70 !Configure the Power Meter to make the measurement 80 OUTPUT @Power;"CONF:POW:AC 20DBM,2,(@1)" 90 !Set the reference calibration factor for the sensor 100 OUTPUT @Power;"CAL:RCF 98.7PCT" 110 !Zero and calibrate the power meter 120 OUTPUT @Power;"CAL?" 130 PRINT "ZEROING AND CALIBRATING THE POWER METER" 140 !Verify the outcome 150 ENTER @Power;Success 160 IF Success=0 THEN 170 !Calibration cycle was successful 180 !

190 !Set the measurement units to Watts 200 OUTPUT @Power;"UNIT:POW WATT" 210 ! 220 !Set the measurement calibration factor for the

sensor 230 OUTPUT @Power;"SENS:CORR:CFAC 97.5PCT" 240 !Set the power meter for a duty cycle of 16PCT 250 OUTPUT @Power;"SENS1:CORR:DCYC 16PCT" 260 ! 270 !Enable the duty cycle correction 280 OUTPUT @Power;"SENS:CORR:DCYC:STAT ON 290 PRINT "MAKING THE MEASUREMENT" 300 !Initiate the measurement 310 OUTPUT @Power;"INIT1:IMM" 320 !... and get the result 330 OUTPUT @Power;"FETC?" 340 ENTER @Power;Reading 350 ! 360 PRINT "The result is ";Reading*1000;"mW" 370 ! 380 ELSE 390 PRINT "THERE WAS A CALIBRATION ERROR!" 400 END IF 410 PRINT "PROGRAM COMPLETED" 420 END

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Pow er Meter Remote Operatio n

Getting the Best Speed Performance

This section discusses the factors that influence the speed of operation (number of readings/sec) of an EPM-P series power meter.

The following factors are those which have the greatest effect upon measurement speed (in no particular order):

• The selected measurement rate, i.e. NORMal, DOUBle, FAST.

• The sensor being used.

• The trigger mode (for example, free run, trigger with delay etc.).

• The output format: ASCii or REAL.

• The units used for the measurement.

• The command used to take a measurement. In addition, in FAST mode there are other influences which are described

in “Fast Mode”, on page 1-74. The following paragraphs give a brief description of the above factors and

how they are controlled from SCPI.

Measurement Rate

There are three possible speed settings NORMal, DOUBle and FAST. These are set using the SENSe:MRATe command and can be applied to each channel independently (E4417A only).

In NORMal and DOUBle modes, full instrument functionality is available and these settings can be used with all sensors. FAST mode is available only for E-series sensors and averaging, limits and ratio/difference math functions are di sabled.

Refer to “Specifications” in the EPM-P Series Power Meters User’s Guide to

see the influence of these speed settings on the accura cy and noise performance of the power meter.

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Power Meter Remote Operation

Getting the Best Speed Performance

Sensor

Different measurement rates are achievable depending on the sensor type being used:

Measurement Rate

Sensor

NORMal DOUBle FAST

8480 series 50 ms 25 ms NA E-series E4410 and E9300 50 ms 25 ms Up to 400 E-series E9320,

AVERage only mode E-series E9320,

NORMal mode

50 ms 25 ms Up to 400

50 ms 25 ms Up to 1000

Trigger Mode

The power meter has a very flexible triggering system. For simplicity, it can be described as having three modes:

• Free Run: When a channel is in Free Run, it continuously takes

measurements on this channel. A channel is in free run when

INITiate:CONTinuous is set to ON and TRIGger:SOURce is set to IMMediate.

• Triggered Free Run: When a channel is in Triggered Free Run

Continuous Trigger, it takes a new measurement each time a trigger even is detected. A channel is in Triggered Free Run Continuous Trigger when INITiate:CONTinuous is set to ON and TRIGger:SOURce is not set to IMMediate.

• Single Shot: When a channel is in Single Shot, it takes a new

measurement when a trigger event is detected and then returns to the idle state. A channel is in Single Shot when INITiate:CONTinuous is set to OFF. Note that a measurement can take several INT/EXT triggers depending on the filter settings. Refer to TRIGger[1]|2:DELay:AUTO <boolean> in Chapter 13 for further information.

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Getting the Best Speed Performance

Note A trigger event can be any of the following:

• The input signal meeting the trigger level criteria.

• Auto-level triggering being used.

• A TRIGger GET or *TRG command being sent.

• An external TTL level trigger being detected.

Trigger with delay

This can be achieved using the same sequences above (apart from the second) with TRIG:DEL:AUTO set to ON. Also, the MEAS? command operates in trigger with delay mode.

In trigger with delay mode, a measurement is not completed until the power meter filter is full. In this way, the reading returned is guaranteed to be settled. In all other modes, the result returned is simply the current result from the filter and may or may not be settled. This depends on the current length of the filter and the number of readings that have been taken since a change in power level.

Pow er Meter Remote Operatio n

With trigger with delay enabled, the measurement speed can be calculated roughly using the following equation:

readings/sec = speed (as set by SENSe:SPEed) / filter length For example, with a filter length of 4 and SENS:SPE set to 20,

approximately 5 readings/sec will be calculated by the power meter. In general, free run mode will provide the best speed performance from

the power meter (especially in 200 readings/sec mode).

Output Format

The power meter has two out put forma ts fo r mea su rement resu lts : ASCii and REAL. These formats can be selected using the FORMat command. When FORMat is set to REAL, the result returned is in IEEE 754 floating-point format (note that the byte order can be changed using FORMat:BORDer) plus <LF> as an end sentinel of the block.

The REAL format is likely to be required only for FAST mode as a means to reduce bus traffic.

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Getting the Best Speed Performance

Units

The power meter can output results in either linear or log units. The internal units are linear and therefore optimal performance will be achieved when the results output are also in linear units (since the overhead of performing a log function is removed).

Command Used

In Free Run mode, FETCh? must be used to return a result. In other trigger modes, there are a number of commands which can be

used, for example, MEASure?, READ?, FETCh? Not e that the MEAS? and

READ? commands are compound commands—they perform a combination of other lower level commands. In general, the best speed performance is achieved using the low level commands directly.

Trigger Count

To get the fastest measuremen t sp e ed the a TRIG:COUNT must be set to return multiple measurements for each FETCh command. For average only measurements a count of 4 is required but 10 is recommended. In normal mode (peak measurements) a count of 50 is required to attain 1000 readings per second.

Fast Mode

In the highest speed setting, the limiting factor tends to be the speed of the controller being used to retrieve results from the power meter, and to a certain extent, the volume of GPIB traffic. The latter can be reduced using the FORMat REAL command to return results in binary format. The former is a combination of two factors:

• the hardware platform being used.

• the programming environment being used.

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Agilent E4416A Programming Guide

Specifications and Main Features

Frequently Asked Questions

User Manual