Agilent 86032A User Manual

User’s Guide

Agilent 86030A Lightwave Component Analyzer System

© Copyright Agilent Technologies, Inc. 2000, 2002 All Rights Reserved. Reproduction, adaptation, or translation without prior written permission is prohibit ed , except as allowed under copyright laws.

Agilent Technologies Part No. 86030-90023 Printed in USA March 2002

Agilent Technologies, Inc. Lightwave Division 3910 Brickway Boulevard Santa Rosa, CA 95403, USA

Notice.

The information contained in this document is subject to change without notice. Companies, names, and data used in examples herein are fictitious unless otherwise noted. Agilent Technologies makes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Restricte d Ri ghts Legend.

Use, duplication, or disclosure by the U.S. Government is subject to res tric tion s as se t forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS 2 52.227-7013 for DOD agencies, and subparagraphs (c) (1) and (c) (2) of the Commercial Computer Software Restricted Rights clause at FAR 52.227-19 for other agencies.

Warranty.

This Agilent Technologies instrument product is warranted against defects in material and workmanship for a period of one year from date of shipment. During the warranty period, Agilent Technologies Company will, at its option, either repair or replace products which prove to be defective. For warranty service or repair, this product must be returned to a service facility designated by Agilent Technologies. Buyer shall prepay shipping charges to Agilent Technologies and Agilent Technologies shall pay shipping charges to return the product to Buyer. However, Buyer shall pay all shipping charges, duties, and taxes for products returned to Agilent Technologies from another country.

Agilent Technologies warrants that its software and firmware designated by Agilent Technologies for use with an instrument will execute its programming instructions when properly installed on that instrument. Agilent Technologies does not warrant that the operation of the instrument, or software, or firmware will be uninterrupted or errorfree.

Limitation of Warranty.

The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by Buyer, Buyersupplied software or interfacing, unauthorized modification or misuse, ope ra tio n outside of the environmental specifications for the product, or improper site preparation or maintenance.

No other warranty is expressed or implied. Agilent Technologies specifically disclaims the implied warranties of merchantability and fitness for a particular purpose.

Exclusive Remedies.

The remedies provided herein are buyer's sole and exclusive remedies. Agilent Technologies shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contract, tort, or any other legal theory.

Safety Symbols.

CAUTION

The caution sign denotes a hazard. It calls attenti on to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the product. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met.

WARNING

The warning sign denotes a hazard. It calls attenti on to a procedure which, if not correctly performed or adhered to, could result in injury or loss of life. Do not proceed beyond a warning sign until the indicated conditions are fully understood and met.

The instruction manual symbol. The product is marked wit h this warning symbol when it is necessary for the user to refer to the instructions in the manual.

The laser radiation symbol. This warning symbol is marked on products which have a laser output.

The AC symbol is used to indicate the required nature of the line module input power.

| The ON symbols are

used to mark the positions of the instrum ent power line switch.

❍ The OFF symbols

are used to mark the positions of the instrument power line switch.

The CE mark is a registered trademark of the European Community.

The CSA mark is a registered trademark of the Canadian Standards Association.

The C-Tick mark is a registered trademark of the Australian Spectrum Management Agency.

This text denotes the

ISM1-A

instrument is an Industrial Scientific and Medical Group 1 Class A product.

Software License

The following License Terms govern your use of the accompanying Software unless you have a separate signed agreement with Agilent.

License Grant. Agilent grants you a license to Use one copy of the Software. “Use” means storing, loading, installing, executing or displaying the Software. You may not modify the Software or disable any licensing or control features of the Software. If the Software is licensed for “concurrent use,” you may not allow more than the maximum numb e r of authorized users to Use the Software concurrently.

Ownership. The Software is owned and copyrighted by Agilent or its third party suppliers. Your license confers no title to, or ownership in, the Software and is not a sale of any rights in the Software. Agilent’s third party suppliers may protect their rights in the event of any violation of these License Terms.

Copies and Adaptations. You may only make copies or adaptations of the Software for archival purposes or when copying or adaptation is an essential step in the authorized Use of the Software. You must reproduce all copyright notices in the original Software on all copies or adaptations. You may not copy the Software onto any public network.

No Disassembly or Decryption. Y ou may not disassemble or decompile the Software unless Agilent’s prior written consent is obtained. In some jurisdictions, Agilent’s consent may not be required for limited disassembly or decompi-

lation. Upon request, you will provide Agilent with reasonably detailed information regarding any disassembly or decompilation. You may not decrypt the Software unless decryption is a necessary part of the operation of the Software.

Transfer. Your license will automatically terminate upon any transfer of the Software. Upon transfer, you must deliver the Software, including any copies and related documentation, to the transferee. The transferee must accept these License Terms as a condition of the transfer.

Termination. Agilent may terminate your license upon notice for failure to comply with any of these License Terms. Upon termination, you must immediately destroy the Software, together with all copies, adaptations and merged portions in any form.

Export Requirements. You may not export or re-expor t the Software or any copies or adaptation in violation of any applicable laws or regu lat io ns.

U.S. Government Restricted Rights. The Software and Documentation have been developed entirely at private expense. They are delivered and licensed as “commercial computer software” as defined in DFARS 252.227-7013 (Oct

1988), DFARS 252.211-7015 (May 1991) or DFARS

252.227-7014 (J u n 19 95) , as a “commercial item” as defined in FAR 2.101(a), or as “Restricted computer software” as defined in FAR

52.227-19 (Jun 1987) (or any equivalent agency regulation or contract clause), whichever is applicable. You have those

rights provided for such Software and Documentation by the applicable FAR or DFARS clause or the Agilent standard software agreement for the product involved.

Limited Software Warranty

Software. Agilent Technologies warrants for a period of one year from the date of purchase that the software product will execute its programming instructions when properly installed on the instrument indicated on this package. Agilent Technologies does not warrant that the operation of the software will be uninterrupted or error free. In the event that this software product fails to execute its programming instructions during the warranty period, Customer’s remedy shall be to return the media to Agilent Technologies for replacement. Should Agilent Technologies be unable to replace the media within a reasonable amount of time, Customer’s alternate remedy shall be a refund of the purchase price upon return of the product and all copies.

Media. Agilent Technologies warrants the media upon which this product is recorded to be free from defects in materials and workmanship under normal use for a period of one year from the date of purchase. In the event any media prove to be defective during the warranty period, Customer’s remedy shall be to return the media to Agilent Technologies for replacement. Should Agilent Technologies be unable to replace the media within a reasonable amount of time, Customer’s alternate remedy shall be a

refund of the purchase price upon return of the product and all copies.

Notice of Warranty Claims. Customer must notify Agilent Technologies in writing of any warranty claim not later than thirty (30) days after the expiration of the warranty period.

Limitation of Warranty. Agilent Technologies makes no other express warranty, whether written or oral, with respect to this product. Any implied warranty of merchantability or fitness is limited to the one year duration of this written warranty.

This warranty gives specific legal rights, and Customer may also have other rights which vary from state to state, or province to province.

Exclusive Remedies. The remedies provided above are Customer’s sole and exclusive remedies. In no event shall Agilent Technologies be liable for any direct, indirect, special, incidental, or consequential damages (including lost profit) whether based on warranty, contract, tort, or any other legal theory.

Warranty Service. Warranty service may be obtained from the neares t Agilent Technologies sales office or other location indicated in the owner’s manual or service booklet.

iii

General Safety Considerations

This product has been designed and tested in accordance with IEC Publi cation 1010, Safety Requirements for El ectronic Measuring Apparatus, and ha s been supplied in a safe condition. The instruction docum entation contains information and warnings which must be followed by the user to ensure safe operation and to ma intain the product in a safe condition.

WARNI NG If this product is not used as specified, the protection provided by the

equipment could be impaired. This product must be used in a normal condition (in which all means for protection are intact) only.

WARNI NG No operator serviceable parts inside. Refer servicing to qualified

personnel. To prevent electrical shock, do not remove covers.

General Safety Considerations iv

1 Installation

Installation 1-2 Step 1. Prepare the Site 1-4 Step 2. Install the Monitor Mount Assembly 1-6 Step 3. Install the Keyboard/Mouse Transmitter and the Work Surface 1-8 Step 4. Confirm Front and Rear Panel Connections 1-9 Step 5. Turn the System On 1-11 Step 6. Configure for Remote Operation 1-12

2 Getting Started

Configuration Options 2-6 Front Panel Featu r es 2- 8 Rear Panel Features 2-11 Software Overview 2-12 File Menu 2-13 Options Me nu 2-20 Tools Menu 2-27 Laser Safety Considera tions 2-30 Accurate Measurements 2 -3 3 Electrostatic Discharge Information 2-44 Quick Start 2-47

3 Measurement Techniques

The Calibrati o ns 3-2 Saving and Reusing 86030A Calibration Sets 3-5 O/O Response and Isola tion Bandwid th Calibration 3-8 O/E Response and Isolation Bandwidth Calibration 3-11 O/E Response a nd Match Bandwid th Calibrati on 3-14 E/O Response and Isolation Bandwidth Calibration 3-23 Agilent 86030A System Example Measurements 3-28 Electrical Mismatch Ripple and its Effects on Measure m e nts 3-29 Magnitude Response and Deviation From Linear Phase of a Lightwave Receiver 3-41 O/E RF Overload Detection Measurement 3-51

Contents-1

Contents

4 Remote Operation

86030A Remote Operation Overview 4-3 COM Fundamentals 4-5 Getting a Handle to the Server Object 4-9 Configuring for DCOM Pro gr amming 4-12 COM Data Types 4-15 Tutorial Using 86030A Remote Operation 4- 18 List of Available Commands 4-25 System Properties 4-29 System Methods 4-32 Data Methods 4-34 Network Analyzer Metho ds 4-39 Calibration Methods 4-41 86032A Testset Methods 4-77 Enumerated Values 4-80 System Messages 4-82 Optical Test Set Error and Action Messages with Descriptions 4-84 System Error and Action Messages with Descriptions 4-86 Network Analyzer Error and Action Messages with Descriptions 4-91 Error Codes and Error Handling 4-94

5 Theory of Operation

System Opera tion 5-2 Lightwave Test Set Operation 5-3 Measurement Calibration 5-6 O/O Measurement Cal ibration 5-7 O/E Measurement Calibration 5-9 E/O Measurement Calibration 5-11 Electrical Measurement Calibration 5-14 O/E Display Sca ling Calculatio ns 5-16 E/O Display Sca ling Calculatio ns 5-17 O/O Display Sc a l ing Calculations 5- 1 8

6System Verification

Lightwave Verification 6-3

Contents-2

If the Lightwave Verification Test Fails 6-7

7 Maintenance

86032A Test Set T roubleshooting Diagnostics 7-7 Modulator Troubleshooting Tips 7-16 Agilent Technologies Support and Maintenance 7-17 Electrostatic Discharge Information 7-19 Returning the System for Service 7-22 Agilent Technologies Servic e Offices 7-25 After Repair 7-26

8 Specifications and Regulatory Information

General Specifications 8-3 Electrical Specifications 8-4 Optical to Optical (O/O) Specifications 8-6 Optical to Electrical (O/E) Specifications 8-7 Electrical to Optical (E/O) Specifications 8-12 Characteristics 8-16 Optical to Electrical (O/E) Characteristics 8-18 Electrical to Optical (E/O) Characteristics 8-21 Regulatory Information 8-24 Declaration of Conformity 8-25

Contents

Contents-3

Step 1. Prepare the Site 1-4 Step 2. Install the Monitor Mount Assembly 1-6 Step 3. Install the Keyboard/Mouse Transmitter and the Work Surface 1-8 Step 4. Confirm Front and Rear Panel Connections 1-9 Step 5. Turn the System On 1-11 Step 6. Configure for Remote Operation 1-12

Installation

The instructions in this chapter show you how to i nst all the 86030A 50 GHz LCA. For overseas sales, the product is shipped without an ac power connector. You should have a local electrician provide and install an ac connector that meets the stand ards for the region. Al so, be sure to set all i nstruments to use the local line vo ltage.

WARNI NG This system is a Safety Class I Product (provided with a protective

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 int erruption of the protective conduc tor inside or outside of the produc t is likely to make the product dangerous. Intentional interruption is prohibited.

WARNI NG To prevent electric shoc k, disconnect the system fro m mains before

cleaning. Use a dry cloth or one slightly dampened with water to clean the external case parts. Do not attempt to clean internally.

WARNI NG HP/Agilent 86032A: No operator serviceable parts inside. Refer

servicing to qualified personnel. To prevent electrical shock, do not remove covers.

WARNI NG HP/Agilent 86032A: For continued protection against fire hazard,

replace line fuse only with same type and ratings. Use a 6.3A 250V fuse. The use of other fuses or materials is prohibited.

WARNI NG HP/Agilent 86032A and HP/Agile nt 86030A: If the syst em and t est set

products are not use d as specified, the protection provided by the equipment could be impaired. These products must be use d i n a normal condition (in w hich all means for protectio n are intact) only.

CAUTION Do not load any software on the 86030A system computer.

1-2

Installation

CAUTION HP/Agilent 86032A and HP/Ag i lent 86030A: This system and test set are

designed for use in INSTALLA TION CATEGORY II and POLLUTION DEGREE 2, per IEC 1010 and 664 respectively.

CAUTION HP/Agilent 86030A: Ventilation Requirements. When instal li ng the produ c t in

a cabinet, the con v ection into and out of t he product must not be restricted. The ambient temperature (outside the cabinet) must be less than the maximum operating temperature of the product by 4°C for every 100 watts dissipated in the cabinet. If the total power dissipated in the cabinet is greater than 800 watts, then forced convection must be used.

CAUTION The warranty and ca l ibration will be voided on systems wh ere the individual

instruments, including fiber-optic cables, RF cables, or GPIB cables are removed by the customer. The system should only be disassembled by an Agilent Customer Engineer. Instruments should not be swapped or removed by non-Agilent personnel.

1-3

Installation

Step 1. Prepare the Site

Your site should accommodate the dimensions, weight s, and powe r cons umption limits shown in the following fig ure.

WARNI NG This system weighs approximately 600 lbs (270 kg). To avoid inj uries,

use proper moving equipment and use extreme car e when installing.

WARNI NG Install the system so the power cords are readily identifiable and are

easily reached by the operator. The power cords are the disconnecting device. They disconnect the mains circuits from the mains supply

1-4

Installation

Step 1. Prepare the Site

before other parts of the system. Alternately, an externally installed switch or circuit breaker (which is readily identifiable and is easily reached by the operator) may be used as a disconnecting device.

CAUTION HP/Agilent 86030A and HP/Agi le nt 86032A: Install the system and tes t se t

according to the enclosure protection provided. This system and test set do not protect against the ingre s s of water. The system and test set protects against finger access to hazardous parts within the enclosure.

CAUTION Before switching on this system, make sure the line voltage selector switch on

the HP/Agilent 86032A lightwave test set’s rear panel is se t to the voltage o f the mains supply, that the correc t fuse is instal led, and t hat the s upply v oltage is in the specified range.

1-5

Installation

Step 2. Install the Monitor Mount Assembly

1 Remove the black end cap from the top of the extrusion. 2 Slide the star knob o nto the lower part of the ex trusion and tighten. 3 Loosen the two black levers on the friction plate and slide it onto the extrusion. 4 Move the friction plate to the desired height and tighten the two black levers. 5 Loosen the star k nob and raise it unti l it stops below the fric tion plate, then

tighten the knob securely to prevent the friction plate, arm, and monitor mount assembly from falling.

WARNI NG If the star knob is not installed properly, the friction plate, arm, and

monitor mount assembly may fall, causing injur y to the user or damage to the monitor and mounting components.

6 Attach the keyboard tray to the monitor mount assembly using the six provided

mounting screws. Tighten with a 1/8” Allen wrench.

7 Attach the LCD monitor to the monitor mount assembly with the pro v id ed

mounting screw. Tighten with a 7/32” Allen wrench. Make sure the moni to r is properly oriented with the alignment pin, then tighte n with a 7/32” Allen wrench.

CAUTION Tighten all hardware on the arm and monitor mount assembly as necessary to

prevent the monitor and keyboard from ti pping unexpectedly.

CAUTION Be careful when swinging the arm around in front of the system to avoid

striking the 8510C and other sys te m components.

8 Replace the black end cap on the extrusion. 9 Connect the monito r cabl e s to the LCD monitor and secure the cabl es to the

bottom of the arm using tie wraps.

1-6

Installation

Step 2. Install the Monitor Mount Assembly

1-7

Installation

Step 3. Install the Keybo a r d/M ouse Transmitter and the Work Surface

Step 3. Install the Keyboard/Mouse Transmitter and the Work Surface

1 Slide the keyboard/mouse transmitter into the plastic holder on the bottom

side of the work surface. Use the cable clamps on the bottom of the work surface to secure the cables.

2 Attach the wor k su rface rails to the rack using a T-25 torx dr iver. 3 Slide the work surface over the rails and secure it using the hardware provided. 4 Route the transmitter cables through the rack and attach to the appropriate

computer connectors using extension cables, if necessary . The Connect button on the transmitter should be towards the plastic holder.

1-8

Installation

Step 4. Confirm Front and Rear Panel Connections

1 Connect the jumper betw een t he L ASER OUTPUT and LASER INPUT on the 86032A

front panel. Refer to Figure 1-1. You must clean the connectors every time the jumper is connected. Refer to

“Cleaning Connectors” on page 2-40.

2 Confirm the cabling of the Agilent/HP 86030A system. Refer to Figure 1-2.

Figure 1-1. Location of the PMF Jumper

1-9

Installation

Step 4. Confirm Front and Rear Panel Connections

Figure 1-2. Agilent 86030A Cabling Configuration

1-10

Installation

Step 5. Turn the System On

1 Plug in the Power Distribution Units (PDU). 2 Turn on the system , and allow it to warm up fo r two hours. 3 When prompted for the password, enter Agilent. 4 Make certain that the laser key is in th e ON position. 5 From the Windows Start menu on the 86030A computer, select Programs,

Agilent, 86030A Main to open the software. A splash screen will appear displaying the software title followed by the appli-

cation screen shown in the following figure.

NOTE Do NOT attempt to close the analyzer appl i cation until the 86030A system

status window says “System Ready .”

6 Perform a system verification. Refer to “Lightwave Verification” on page 6-3.

1-11

Step 6. Configure for Remote Operation

This step provides instructions for configuring and installing the 86030A controller software on a client PC, which is external to the analyzer system. This step is only necessary if you will be opera tin g the 86030A remotely. For information on available commands and remote operation, refer to Chapter 4,

“Remote Operation”.

Client PC Minimum Requirements

Configure the Client PC for a Private LAN Interface

• Windows NT 4.0 Service Pack 6

• LAN Card

These instructions assume that your computer already has a second ne twork adapter (LAN card) and a TCP/IP protocol installed. The first LAN card must have a static IP to work on your public LAN in the presence of the second card.

1 On the client PC, click Start, Settings, Control Panel. 2 Double-clic k Ne tw ork. 3 Select the Protocols tag and click Properties. 4 In the list displayed, select the type of LAN adapter card that you have installed

in the client PC.

5 Click Adpater and select the second LAN card. 6 Click Specify, IP Ad dress and enter the fol lowing settings.

• For IP Address, enter 192.168.000. 001

• For Subnet Mask, enter 255.255.255.0

• For Default Gateway: enter 192.168.000.001

7 Click Apply.

Installation

Step 6. Config ure for Remote Operat ion

NOTE If you get an error at least twice, indicating the adap te r card has an empty

primary window address, click Yes.

8 For the TCP/IP Properties window, click OK. 9 On the Network window, click Close.

10 Restart the PC.

Install the Controller Software

1 Insert the disk labled “Agilent 86030A Controller Software” into the client

conputer CDROM drive.

2 Locate the file “86030A_Inst.exe” on the disk. 3 Double-click the file to start the installation process. 4 The window below will appear, indicating the setup process has begun.

• If a window appears stating that the Windows installer is an old er versio n, click OK to allow the setup to upgrade the installer. It may take a few moments for the Welc o m e sc reen to appear.

• Restart the computer after the installer is upgraded so the setup may continue.

5 When the InstallShield window appears, the installation process has begun.

Click Next.

6 Enter the User Nam e and Organization, then click Next. 7 Select Complete setup, and cli c k Ne x t. 8 Click Install. The installation may take a few minutes. 9 Click Finish to complete the installation.

1-13

Installation

Step 6. Configure for Re m ote Ope ration

1-14

System Overview 2-2 Configuration Options 2-6 Front Panel Featu r es 2-8 Rear Panel Features 2-11 Software Overview 2-12 File Menu 2-13 Options Menu 2-20 Tools Menu 2-27 Laser Safety Considera tions 2-30 Accurate Measurements 2-33 Electrostatic Discharge Infor m ati on 2-44 Quick Start 2-47

Getting Started

System Overview

The Agilent 86030A 50 GHz lightwave component analyzer provides accurate and repeatable characterization of electro-optical , opt ical, and electri cal components.

You can characterize components such as O/E photodiode receivers, E/O photodiodes, lightwave modulators, and other opti cal and electrical components used in 40 Gb/s lightwave systems.

The Agilent 860 30 A system consists o f the following item s:

• 85107B vector network analyzer system

• 86032A 50 GHz lightwave test set

• system softwar e

• personal comput er, serving as the system c on t roller

• controller software for a client computer

NOTE You can control the 86030A directl y us in g the sy stem computer, or remotely

using the controller software on a client computer.

2-2

Getting Started

System Overview

2-3

Getting Started

System Overview

Calibrated Measurements

One of the key benefits of the 50 GHz lightwave component analyzer is its ability to perform calibrated measurements of optical component s. The system contains an O/E receiver that has been factory calibrated in magnit ude , and characterized in phase. The ability to make calibrated measure men ts assures accuracy , reliability, and confidence in the components being measured. Additionally, the laser source, optical modulator, and calibrated O/E receiver are temperature stabilized which also improves the accuracy and repeatability of measurements.

Verification Device

A verification device is included with the N1012A Lightwave Verification Kit. The device is an O/E photodetector and includes associated amplitude and phase data. You can use this verification device at any time to verify the measurement integrity of your system. The 86030A system provides a guided verification routine that measures the verific ati on de vice , and displ ays a graph of its response versus acceptable tolerances. The verif icat ion device allows yo u to periodically monitor system calibration, and detect when the optical test set needs to be recalibrated. You can also use the device to resolve uncertainty if unexpected results are obtained from a test device. This verification capability provides confi dence in the measurem ent integrity of the sy stem.

Measurement Software

Guided measurement software provides an easy-to-use operator interface. It provides pictorial diagrams of interconnections for configuration, calibration, and measurements. On-screen prompts also guide you through the entire measurement pr oc ess, from the calibra tion to the measure m ent.

Data Management

Display, analysis, and archiving of data is easy and straightforward with the system. The measured data is displayed on the Agilent 8510C network analyzer. Full use of the analyzer’s func tions such as markers , data formats, and data scaling features are available. Data can be archived to disk in either ASCII text or Microsoft

Excel formats. The included Excel software allows data to be displayed and analyzed using standard Excel features and formats. Data connectivity to a local area network (LAN) is provided via a LAN card in the system’s PC.

1. Microsoft and Excel are registered U.S. trademarks of Microsoft Corporation.

2-4

System Overview

System Accessories

The accessories described below may be shipped with your system.

Table 2-1.System Accessories

Description Agilent Model/Part Number

Verification Kit N1012A 86030A User’s Guide 86030-90023

2.4 mm 8510C Calibration Kit 85056A

2.4 mm Flexible Cables 85133F Controller (Client) Software CDROM 86030-10004 86030A Operating System Software CDROM 86030-10002 86032A Calibration Coeff icients Floppy Disk Unique to 86032A Test Set Bias Network 0.045 - 50 GHz (2.4 mm)

11612B

Getting Started

a. The bias network is not part of the 86030A shipment, yet it may be helpful when

measuring modul ators.

2-5

Getting Started

Configuration Option s

Configuration Options

The standard Agilent/HP 86030 A sy stem is supplied with FC/PC optical connectors. If other optical connectors are desired, ordering one of the following connector options will replace the FC/PC connectors with the desired opti cal connectors.

Table 2-2. Available Options for the 86030A System

Option Number Description Part Number

011 Diamond HMS-10 connector interface 08154-61701 013 DIN 47256 connector interface 08154-61703 014 ST optical connector int erface 08154-61704 017 SC optical connector interface 08154-61708 230 220-240 VAC operation

WARNI NG During measurements, laser light emits from the front-panel OPTICAL

OUTPUT connector and the LASER OUTPUT connector. This light

originates from the system ’s laser source. Always keep these connectors covered when not in use.

NOTE If you would like to change the optical connectors to a different type, you can

order a quantity of seven of the replac em ent part number, shown above.

2-6

Getting Started

Configuration Options

CAUTION The warranty and ca l ibration will be voided on systems wh ere the individual

instruments are removed by the customer. The system should only be disassembled by a Agilent Technologies Cust o mer Engineer. Instruments should not be replaced by non-Agi lent Technologies personnel.

Measuremen t ac curacy—it’s up to you!

Fiber-optic connectors are easily damaged when connected to dirty or damaged cables and accessories. The 86030A’s front-panel SOURCE OUTPUT and RECEIVER INPUT con- nectors, 86032A Laser Output and External Laser Input are no exception. When you use improper cleaning and handling techniques, you risk expensive instrument repairs, damaged cables, and compromised measurements. Before you connect any electrical cable to the 86030A, refer to “Electrostatic Discharge Information” on page 7-19.

2-7

Getting Started

Front Panel Features

Figure 2-3. 86032A Front Panel

2-8

Getting Started

Front Panel Features

1. LASER Key Turns the laser on and off. Note that the laser is not operational until it is activated by the 86030A software program. You can turn on the laser manually from the Diagnostic software. From the Windows Start menu, select Programs, Agilent Technologies 50 GHz LCA, 50 GHz Diagnostics. From the Laser menu, click Laser ON. Make sure the laser key on the 86032A is i n th e on position.

WARNI NG Do NOT, under any c ircums tances, look in to the op tical ou tput or a ny

fiber/device attached to the output while the laser is in operation.

Refer to “Laser Safety Considerations” on page 2-30.

2. Laser LED Indicates the state of the laser. When the LED is lit, the laser is on. Note that the laser is not operational until it is activated by the 86030A software program. You can turn on the laser manually from the Diagnostic software. From the Windows Start menu, select Programs, Agilent Technol ogies 50 GHz LCA, 50 GHz Diagnostics. From the Laser menu, click Laser ON.

3. E/O LED When on, indicates the internal measurement path is selected for an E/O (electrical-to-optical) device.

4. E/E LED When on, the internal measurement path is selected for an E/E (electrical-to-el ect rical) device. The test set is in a bypass mode for E/E device selection and the laser is shut down. The test set will need to be in the ON position for use in E/E mode.

5. O/E LED When on, the internal measurement pat h is selected for an (optical-to-electrical) O/E device.

6. O/O LED When on, the internal measurement path is selected for an (optical- t o -optical) O/O dev i c e .

7. DIRECTIONAL COU PLER

INPUT

8. DIRECTIONAL COU PLER

COUPLED

9. DIRECTIONAL COU PLER

TEST PORT

10. Grounding Receptacle Ground path that is provided to connect a static strap.

11. RF OUTPUT RF output that provides RF drive power for E/O devices.

12. OPTICAL RECEIVER RF

OUTPUT

Input for the optical direction coupler. This port is usually connected to the OPTICAL OUTPUT.

Port for the coupler output. This port is usually connected to the OPTICAL RECEIVER INPUT.

Coupler output port (transmission) or test port (reflection).

Test set optical receiver output.

2-9

Getting Started

Front Panel Features

13.OPTICAL RECEIVER INPUT

14. OPTICAL OUTPUT Modulato r output.

15. LASER INPUT External laser input.

16. LASER OUTPUT Output of internal laser.

17. POWER Switch Turns the instrument power on.

Test set optical receiver input.

CAUTION Use care in handling optical connectors. Damage to an optical te st port

connector can require a costly repair and lost productivity for the system. Keep optical cables connected to the te st ports to protect the connectors from damage. Also, make sure to clean the connectors before each use. Refer to

“Accurate Measurements” on page 2-33.

2-10

Rear Panel Features

Getting Started

Rear Panel Features

Figure 2-4. 86032A Rear Panel

1. Remote Programming

Connector

2. Laser Remote Shutdown Turns the laser on or off. When the BN C short is connected, the

3. Line Module This assembly houses the line cord connector.

4. RF REF OUTPUT RF output of the test set that is used to route the 8517B electrical

5. EXT ALC DC output from the leveling detector on the internal ALC circuit.

6. RF INPUT RF input port from the source output of the network analyzer.

Allows for remote control of the instrument’s front panel via the 86030A software installed on the system PC.

laser is enabled. When removed, the laser is disabled.

test set for phase locking.

This output is routed to the EXT ALC port of the network analyzer source.

2-11

Getting Started

Software Overview

The 86030A software sets up instrument states on the network analyze r and lightwave test set, and guides you through the measurement calibration and measurement pro c e dures. The program combines the measur ement calibration traces with the calibration data response of the lightwave receiver, and loads the result back into the network analyzer to provide calibrated lightwave measurements. You can save and view trace data using Microsoft Excel, and manually control the 86032A test se t operation.

2-12

Getting Started

File Menu

The File menu is used to save data as either an ASCII text file or an Excel worksheet. Using Graph Excel Data allows you to automatically view saved data in an Excel worksheet as tabular data, or as graphical data in log magnitude, phase or delay formats. The File menu is also used to exit the application.

Save Data

Text File Text File allows you to save data as an ASCII text file in four different formats:

• Raw Data

• Log Magnitude

• Phase

• Delay

2-13

Getting Started

File Menu

Raw Data saves trace data in a ASCII text format (.txt) known as a CITIFile (common instrumentation trans fer and interchange file). The CITIFile format is useful when data will be exchanged with another network analyzer. The data file saves both real and imaginary pairs independent of the format of the active screen. However, any trace smoothing that was applied to the measurement will not be saved (that is, Smoothing On is activated from the 8510C Response menu).

Formatted Data, Log Mag, Phase, Delay saves trace data with any trace smoothing tha t w as a pp lied t o t he m easu remen t (t ha t is , Smoo th ing On i s acti vated from the 8510C Response menu), but only retains the values of the format that was selected for saving (that is, Log Magnitude, Phase, or Delay).

Excel File Excel File allows you to save the trace display as a Microsoft Excel workbook

(.xls extension). The Ex cel f orma t is usef ul when you want t o vi ew or ed it th e data in an Excel spreadsheet.

Raw Data saves both re al and imaginary pairs independent of the format of the active screen. This data can later b e v iewed in either Log Ma gnitude or Phase format from the File, Graph Excel Data menu. Any trace smoothing that was applied to the measurement will not be saved (that is, if Smoothing On is activated from the 8510C Response menu).

Formatted Data saves trace data and any trace smoothing that was applied to the measurement, bu t only viewed using the format that the data was originally saved (that is, Log Magnitude, Phase, or Delay).

2-14

Getting Started

File Menu

Log Mag saves the log magnitude format. This is the standard Cartesian format used to display magnitude-onl y m ea surements of insertion loss, return loss, or absolute power in dB versus frequency.

Phase saves the phase of data versus frequen c y in a Cartesian forma t. Delay saves the group delay format, with marker values given in seconds.

Group delay is the measurement of signal transmission time through a test device. It is defined as the derivative of the phase char acte ri st ic wi th re sp ect to frequency. Since the derivative is basically the instantaneous slope (or rate of change of phase with frequency), a perfectly l inear phase shift results in a constant slope, and therefore a constant gro up delay.

Graph Excel Data

Raw Data Data allows you to view trace data in either Log Magnitude o r P ha se format.

However, any trace smoothing that was applied to the measurement will not be captured. (that is, if Smoothing On was activated from the 8510C Response menu).

Log Magnitude displays the trace data in Cartesian format as logarithmic (dB) magnitude versus frequency.

Phase displays the trace data in Cartesian format as phase versus frequency.

Formatted Data, Formatted Data allows you to view trace data in the format that it was saved

(that is, Log Magnitu de, Phase, or Delay) includ in g an y t ra c e smo o thing that was applied to the measurement

Log Mag displays the log magnitude format. This is the standard Cartesian format used to display magnitude-only measurements of insertion loss, return loss, or absolute power in dB versus frequency.

2-15

Getting Started

File Menu

Phase displays the phase shift of data versus frequency in a Cartesian for m a t. Delay displays the group del a y for mat, with marker values given in seconds.

Group delay is the measurement of signal transmission time through a test device. It is defined as the derivative of the phase char acte ri st ic wi th re sp ect to frequency. Since the derivative is basically the instantaneous slope (or rate of change of phas e w i th frequency), a perfe c tly linear phase shif t re sults in a constant slope, and therefore a constant group delay. See Figure 2-5.

Figure 2-5.

Note, however, that the phase characteristic typically consists of both linear and higher order (deviations from linear) components. The linear component can be attributed to the electrical length of the test device, and represents the average signal tra nsit time. The higher order componen ts are interpreted as variations in transit time for diff erent frequencies, and represent a source of signal distort ion. See Figure 2-6.

2-16

Figure 2-6.

Getting Started

File Menu

Group Delay τ

dφ–

-------- -==

dω

in Radians in Radians

1–

dφ

----------- -

------

360°

⋅=

φ in Degrees

f in Hz (ω 2πf)=

The analyzer compu tes group delay from th e phase slope. Phase data is used to find the phase change, ∆φ, over a specified frequency aperture, ∆ƒ, to obtain an approximation for the rate of change of phase with frequency (Figure 2-7). This value, τ

, represents the group delay in seconds a ss uming

linear phase change over ∆ƒ. It is important that ∆φ be ≤180°, or errors will result in the group de lay data. These errors c a n be significant for l ong delay devices.

Figure 2-7.

2-17

Getting Started

File Menu

When deviations fr om linear phase are pres ent, changing the frequency step can result in different values for group delay. Note that in this case the computed slope var ies as the aperture ∆ƒ is increased (Figure 2-8). A wider aper- ture results in loss of the fine grain variations in group delay. This loss of detail is the reason tha t in a n y comparison of group delay data it is important to know the aperture use d t o mak e th e mea su rement.

Figure 2-8.

In determining the group delay aperture, there is a trade-off between resolution of fine detai l a nd ra pid variations in g ro u p delay, which can look like a noisy trace. Th es e rapid va ria tio ns can be red uc ed by incre asi ng the a per tur e, but this will tend to smooth out the fine detail. More detail will become visible as the aperture is decreased, but the varia ti ons will als o incr e ase , possi b ly to the point of obscuring the detail. A good practice is to use a smaller aperture to assure that small variations are not missed, then incre a s e the ape rture to smooth the trace.

2-18

Exit

Exit closes the 86030A software application.

Getting Started

File Menu

2-19

Getting Started

Options Menu

The Options menu allows you to set and monitor system functions.

Auto Bias

Auto Bias allows you to bias the modulator to operate at quadrature or at maximum optical power. Under typical circumstances the lightwave modulator is biased to operate at qu adrature. Quadrature is the point where the slope of the optical power versus voltage is maximally positive. Refer to Figure 2-9.

2-20

Getting Started

Options Menu

Power at Quadrature (1)

Voltage at Quadrature (2)

Figure 2-9. Effect of Bias V oltage on Modulat ed Optical Power

The point midway between the max im um and mini m um optical power points, on the positive slope of the bias curve. The quadrature point allows maximum optical power variations versus modulation vol tag e.

The voltage where the optical power is at the quadrature point. The auto-biasing routine sele c t s this voltage to bias the internal optic al modulator.

2-21

Getting Started

Options Menu

Voltage at Maximum Optical Power (3)

Voltage at Minimum Op tical Power (4)

Maximum Optical Power (5)

Minimum Op tical Power (6)

The voltage at which the maximum output power occurs (V

The voltage at which the minimum output power occurs (V

min

max

The maximum optical output power.

The minimum optical output power.

How to Determine if Auto Bias Values are Reasonable

The following formulas will help you to determine if the modula tor auto bias settings are val id. R efe r to Figure 2-9 on page 2-21

Voltage at Maximum Optical Power – Voltage at Minimum Optical Power should between 3 and 6 volts.

Vmax Vmin+

Voltage at Quadrature should be approximately Maximum Optical Power should be > 3 dBm

Power at Quadrature should be > 0 dBm Tip: You can set this value manually. From the Tools menu, click on Mo nitor

T es t Set. I n th e Mo dif y Bia s Voltage text box, ent er t he de si re d v alu e an d th en click Set Modulator Bias Voltage to.

Refer to “Modulator Troubleshooting Tips” on page 7-16 for more informatio n.

----------------------------------

2-22

Getting Started

Options Menu

Auto Bias At Cal

Auto Bias At Cal when selected, an auto bias is performed before each calibration. The auto bias is performed after you click either Resp Cal or Resp-Isol Cal.

Customize

Customize allows you to set and monitor certain parameters that affect the operation of the system.

Standard The Standard Settings dialog box allows you to set and monitor certain param-

eters controll ed by the network anal yz e r.

2-23

Getting Started

Options Menu

GPIB Address displays the current address setting for the ana l yzer. This value must correspond to the actual address on the 8510 GPIB address bus. Failure of these two numbers to match will prevent operation.

Average Factor is used to improve the sensitivity of the measurement. For the Step Mode of operation for e ach m odulation frequency point, mu lt iple data point samples (equ a l to the number of averages) are mea s ured by the system, and averaged together to provide a single averag e value . Averaging multiple data poi nts together reduces the effects of noise on the measurement. The improvement in sensitivity is equ a l to:

dB 10log10number of averages()=

Note the 8510C network analyzer only averages with powers of 2 (that is, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, and so on). Therefore, if an averaging factor of 500 is set on the analyzer, the analyzer will default to 256 averages.

Bias Interval, mins corresponds to the number of minutes before prompting you to perform another modulator auto bias.

Refl Standard % corresponds to the percent of refl ection of the Reflection Standard used in the system. This is useful for O/O reflection modes.

Averaging when selected, the network analyzer will perform averaging at each data point.

Split Screen E/O when selected, th e ne tw ork analyzer displays both the bandwidth and reflection measurement on the display. This function is only valid with an E/O Bandwidth and Reflection measurement. Bandwidth is

2-24

Getting Started

Options Menu

displayed on c ha n nel 1 and Reflection is displayed on chan nel 2. When this function is cleare d, use the network anal y z er front panel channel buttons to select between the two measurements.

Time Date Stamp when selected, the time and date st a m p is applied to the trace on the network analyzer.

Scale Excel Chart when selected, the trace data save d fr om the netw ork analyzer will be auto-scaled to fit into an Excel chart.

Step Sweep/Ramp Sweep toggles between st ep sw eep and ramp sweep modes.

Step Sweep is a digital sweep beginning at the start frequency and ending at the stop frequency with the so urce phase locked and the data measured at a frequency interval determined by the number of points selected on the network analyzer (STIMULUS MENU, STEP). An up arrow on the trace identifies the data point just measured. The step mode is recommended when you need the best modulation frequency acc uracy and re pe atab ility.

Dwell time prior to measurement a t ea c h frequency point is controlled by th e sweep time setting. Measurement time at each point is determined by the averaging factor.

NOTE System specifications are only warranted when using the Step Sweep mode of

operation. Ramp Sweep selects continuous linear analog sweeps beginning at the start

frequency and ending at th e stop frequency. The rate is determined by the sweep time, measuring data at frequency intervals set by the number of points. (8510 access, STIMULUS MENU, RAMP)

Advanced The Advanced Settings dialog box allows changing of default power values.

2-25

Getting Started

Options Menu

External Leveling when checked, the system uses external leveling. Whe n cleared, the system uses internal leveling. Normal system operation uses external leveling.

Src Pwr, E to X, dBV for E/O mode and E/ E mode, dis plays the 83651A external leveling source power.

Src Pwr, O to X, dBV for O/E mode and O/O mode, displays the 83651A external leveling source power.

Default Settings when selected, resets the source power to its factory default values.

Setting the Power at the RF Output Port

CAUTION Do not exceed -3 to +5 dBm at the 8510 RF output port. Due to variations in

The power at the 860 30 A RF output port is set at the fa cto ry for a nominal 0 dBm. You can change the RF output power level by followin g these steps:

1 Connect a power meter to the R F ou tput po rt. 2 On the 8510, press Span, 0, Hz, Center Frequency, 25, GHz. 3 In the 86030A Options menu, click Customize, Advanced. 4 In the Src Pwr, EtoO, dBV box, enter the power value and click OK. Make the

changes to the power level in small deviations from the default state.

amplifier gain, error messages may appear on the analyzer screen. Reduce or increase the power setting to remove the error mes sages.

System Verification

A System Verification performs a measurement on the verification device over the entire frequenc y range. The verifica tion device is the 83440D Option 050 lightwave detector supplied in the N1012A verification kit. Once the verification is completed, the results are displayed in an Excel wor ksh eet alo ng with the error bars that were computed from the factory measurement of the verification device. For the system to pass the verification test, the verification device trace must fit within the error bars. A pass or fail indicator is displayed at the bottom of the worksh eet. Refer to “Lightwave Verification” on page 6-3 for more informatio n .

2-26

Getting Started

Tools Menu

The Tools menu is used to monitor and modify 86032A test set param ete rs.

Modify Test Set

Curent Laser Output Power (dBm) displays the valu e of the laser power coming from the LASER OUTPUT port of the test set.

Set Laser Output Power to:(dBm), when Modify Power is selected, the value will be updated to the value specified in this text box.

2-27

Getting Started

Tools Menu

Modify Power sets the internal laser of the 86030A test set to the power specified in the Modify Power text box. This value will be used until you restart the 86030 A so ftware. Valid settings are from 0 dBm to 10 dB m .

Set Optical O utput Pwr to Nominal Setting sets the laser to its factory default setting. When the software is start ed , the power always defaults back to the factory setting.

Current Modulator Bias Voltage (V) displays the value last applied to the internal modulator bias tee attached to the optical modula tor.

Set Modulator Bias Voltage to: (V), when Mo di fy Bias Voltage is selected, the bias voltage will be updated to the value specified in this te xt box . The range is –10 to +10 volts.

Modify Bias Volt age sets the bias voltage to the va lue entered in the Set Modulator Bias Voltage text box.

Turn Laser On turns on the laser inside the 86032A test set. This command does not change the power of the laser. This function is useful in E/O mode when you may want to use the internal high power laser as a stimulus for testing optical mo dul a tors. The optical po w e r is normally off in the E / O m o de .

Turn Laser Off turns off the laser inside the 86032A test set. This command does not change power of the laser. If the laser is turned off and then turned back on again, the original power of the laser will be used.

Set Mod. Bias to Quadrature when clicked, performs an auto bias on the modulator and sets the mod ul a tor bias voltage to the midpoint of the mo dulated optical power curve. Biasing at quadrature maximizes the modulation response and minimize s dis tortion of the modulated sig nal .

The power of the laser is assumed to have been previously set. If the laser power is too low or if the laser is turned of f, the auto bias routi ne will fail and display a message indicating that a bias point could not be found. For this command to func tio n p rop erly, the laser po wer sho uld be lef t a t it s defa ult set ting or set to a reasonable power value (between 3 and 12 dBm) prior to performing this function.

Set Mod Bias to Maximum when selected, performs an auto bias on the modulator and sets the modulator at maximum optical output power.

The power of the laser is assumed to have been previously set. If the laser power is too low or if the laser is turned of f, the auto bias routi ne will fail and display a message indicating that a bias point could not be found. For this command to function properly , the laser power should be left to its default setting or set to a reasonable power value (between 3 and 12 dBm) prior to performing this function.

2-28

Getting Started

Tools Menu

E/X when selected, puts the 86032A test set into electrical excitation mode . The RF signal coming in to the optical test set will be routed out of the front panel connector marked “RF OUTPUT.” Therefore, the RF signal will not be routed to the optical modulator in the test set.

O/X when selected, puts the 86032A test set into optical excitation mode. The RF signal comin g into the test set will be routed to the optical modulator, rather than out the front pane l connector marked “RF OUTPUT.”

Monitor Test Set

The Monitor Test Set dialog box is used to monitor and update the power and voltage levels of the 86032A test set.

Optical Output Power (dBm) displays the current optical power coming from the 86032A OPTICAL OUTPUT port.

Optical Receiver Input (dBm) displays the current optical power coming into the 86032A OPTICAL RECEIVER INPUT por t.

Current Modulator Bias Setting (V) displays the current value of the 86032A bias voltage on the modulator.

2-29

Getting Started

Laser Safety Co nsiderations

Laser Safety Considerations

Laser Safety Laser ra diation in the ultraviolet and fa r infrared parts of the spectrum c an

cause damage primarily to the cornea and lens of the eye. Laser radiation in the visible and near infrared regions of the spectrum can cause damage to the retina of the eye.

The CW laser sources use a laser from which the greatest dangers to exposure are:

1 To the eyes, where aqueous flare, cataract formation, and/or corneal burn are

possible.

2 To the skin, where burning is possible.

WARNI NG Do NOT, under any c ircums tances, look in to the op tical ou tput or a ny

fiber/device attached to the output while t he laser is in operation.

This system should be serviced onl y b y au thorized personne l. Do not enable the laser unless fiber or an equivalent device is attached to the

optical output connector.

CAUTION Use of controls or adjustments or performance of procedures other than those

specified herein can re s ult in hazardous radiation exposu re.

Laser Classifications

United States-FDA Laser Class IIIb. The system is rated USFDA (United States Food and Drug Administration) Laser Class IIIb according to Part 1040, Performance Standards fo r L igh t Em i tting Products, from the Cente r for Devices and Radiological Health.

Internationa l -IEC Lase r Class 3B. Th e syst em is rat ed IEC (Int ern ati ona l El ectrotechnical Commission) Laser Class 3B laser products according to Publication 825.

International-IEC 825. The sy st em helps satisfy the I nt ernational (IEC8 2 5) safety requirements with the use of a REMOTE SHUTDOWN and a KEY SWITCH.

2-30

Getting Started

Laser Safety Consideratio ns

Laser Warning Labels

The 86030A is shipped with the followi ng war ni ng l abel s. For syste m s us ed outside of the USA, both laser aperture and laser warning label s wi ll be included with the shipment ( The labels are lo c a ted in the same bo x a s this manual). Place th ese labels direc tly over the USA laser w a rning and aperture labels.

Figure 2-10. Laser safety label locations

Electrical Safety The electrical safety considerations are documented in the section “General

Safety Considerations ” on page iv. Familiarize yourself with the saf ety mark-

ings and instru c tions before operating this system.

Service Limited service may be performed on this system in accordance with informa-

tion provided in Chapter 7, “Maintenance”. For all othe r repairs the system must be returned to Agilent Technologies.

Maintenance On a daily basis, practice the techniques for proper connector use and care.

Refer to the Lightwave Connection Techniques for Better Measurements booklet. If you should ever need to clean the cabinet, use a damp cloth only.

CAUTION Exposure to tempera tu res above 55°C may cause the front panel fiber to

retract. In this case a matching compound can be used to temporarily improve return loss. However, the system sho uld be returned to Agilent Technologies for repair.

CAUTION This product i s designed for use in INSTA L LATION CATEGORY II and

POLLUTION DEGREE 2, per IEC 1010 and 664 respectively.

2-31

Getting Started

Laser Safety Co nsiderations

Learn proper connector care

When you use improper cleaning and handling techniques, you risk expensive system repairs, damaged cables, and compromised measurements. Repair of damaged connectors due to improper use is not covered under warranty.

Clean all cables before applying to any connector. Refer to the Lightwave Connections Techniques for Better Measurements booklet.

2-32

Getting Started

Accurate Measu rem e nts

Accurate Measurements

Today, advances in measurement capabilities make connectors and connection techniques more important than ever. Damage to the connectors on calibration and verification devices, test ports, cables , and ot her device s can degrade measurement accuracy and damage instruments. Replacing a damaged connector can cost thousands of dollars, not to mention lost time! This expense can be avoided by observing the simple precautions presented in this book. This book also contains a brief list of tips for caring for electrical connectors.

Choosing the Right Connector

A critical but often overlooked factor in making a good lightwave measure ment is the selection of the fiber-optic connector. The differences in connector types are mainly in the mechanic a l assembly that holds the ferrule in position against another identical ferrule. Connectors also vary in the polish, curve, and conce ntricity of the core w ithin the cladding . Mating one style o f cable to another requires an adapter. Agilent Technologies offers adapters for most instruments to allow testing with many different cables. The Figure 2-11

on page 2-34 shows the basic components of a typical connector.

The system tole ranc e for reflection and in se rtion loss must be kno wn w hen selecting a connector from the wide variety of currently available connectors. Some items to consider when selecting a connector are:

• How much insertion loss can be allowed?

• Will the connector need to make multiple connecti ons ? Some con ne ctors are

better than others, and some are very poor for making repeate d connections.

• What is the reflection tolerance? Can the system take reflection degradation?

• Is an instrument-grade connector with a pre ci si on core alig nmen t re qu ir ed ?

• Is repeatability tolerance for reflection and loss important? Do your specifica-

2-33

Getting Started

Accurate Measurements

tions take repeatability uncertain ty into account?

• Will a connector degrade the return loss too much, or will a fusion splice be required? For example, many DFB lasers cannot operate with reflections from connectors. Often as much as 90 dB isolation is needed.

Figure 2-11. Basic components of a connector.

Over the last few ye a rs, the FC/PC style co nnector has emerged a s the most popular connector for fiber-optic applications. While not the highest performing connector, it represents a good compromise between performance, reliability, and cost. If properly maintained and cleaned, this connector can withstand many repeated connections.

However, many instrument specifications require tighter tolerances than most connectors, including the FC/PC style, can deliver. These instruments cannot tolerate connectors with the l arge non-concentricities of the f ibe r com m o n with ceramic style ferrules. When tighter alignme n t is required, Agilent instrument s ty pically use a connector such as the Di am ond H MS- 10, which has concentric tolerances within a few tenths of a micron. Agilent then uses a special universal adapter, which allows other cable types to mate with this precisio n connector. See Figure 2-12 on page 2-35.

2-34

Getting Started

Accurate Measu rem e nts

Figure 2-12. Universal adapters

The HMS-10 enca se s the fiber within a soft nickel silver (Cu/ Ni/Zn) center which is surrounded by a tough tungsten carbide casing, as shown in

Figure 2-13.

Figure 2-13. Cross-section of the Diamond HMS-10 connector.

The nickel silver allows an active centering process that permits the glass fiber to be moved to the desired positi on. This process first stakes the soft nicke l silver to fix the fiber in a near-center location, then uses a post-active staking to shift the fiber into the desired position within 0.2 µm. This process, plus the keyed axis, allo ws very precise core-to-core alignm ents. This connecto r is found on most Agilent lightwave instruments.

2-35

Getting Started

Accurate Measurements

The soft core, wh ile allowing precis e ce n tering, is also the c h ief liability of the connector. The soft material is easily damaged. Care must be taken to minimize excessive scratching and wear. While minor wear is not a problem if the glass face is not affected, scratches or grit can cause the glass fiber to move out of alig nment. Also, if unkeye d co nnecto rs ar e used , the nicke l sil ver ca n be pushed onto the glass surface. Scratches, fiber movement, or glass contamination will cause lo s s of sign al and increa sed re flect ion s, resu ltin g in p oor retu rn loss.

Inspecting Connectors

Because fiber-optic connectors are susceptible to damage that is not immediately obvious to the naked eye, bad measurements can be made without the user even being aware of a connector problem. Although microscopic examination and return loss measurements are the best way to ensure good connections, they are not always practical. An awareness of potential problems, along with good cleaning practices, can ensure that optimum conne ctor performance is maintained. With glass-to-glass interfac es, it is clear that any degradation of a ferrule or the end of the fiber, any stray particles, or finger oil can have a significant effect on connector performance.

Figure 2-14 shows the end of a clean fiber-optic cable. The dark circle in the

center of the micrograph is the fiber’s 125 µm core and cladding which carries the light. The surrounding area is the soft nickel-silver ferrule. Figure 2-15 shows a dirty fiber end from neglect or perhaps improper cleaning. Material is smeared and gr ou nd i nto t he end o f t he f ib er cau si ng l igh t sc att erin g an d po or reflection. Not only is the precision polish lost, but this action can grind off the glass face and destroy the connector.

Figure 2-16 shows physical damage to the glas s fib er end caused by either

repeated connections made without removing loose particles or using improper cleaning tools. When severe, the damage on one connector end can be transferred to another good connecto r that comes in contact with it.

The cure for these p roblems is discipline d c onnector care as desc ribed in the following list and in “Cleaning Connectors” on page 2-40.

Use the following guidelines to achieve the best possible performance when making measurements on a fiber-optic system:

• Never use metal or sharp objects to clean a connector and never scr a pe the connector.

• Avoid matching gel and oils.

2-36

Figure 2-14. Clean, problem-free fiber end and ferrule.

Getting Started

Accurate Measu rem e nts

Figure 2-15. Dirty fiber end and ferrule from poo r cl eaning.

Figure 2-16. Damage from improper cleaning .

2-37

Getting Started

Accurate Measurements

While these often work well on first insertion, they are great dirt magnets. The oil or gel grabs and holds grit that is then ground into the end of the fiber. Also, some early ge ls were designed for use with the FC, non-contacting connectors, using small glass spheres. When used with contacting connectors, these glass balls can scratch and pit the fiber. If an index matching gel or oil must be used, apply it to a freshly cleaned connector, make the measurement, and then immed ia tely clean it o ff. Never use a gel for lo n ger-term connections and never use it to improve a damaged connector. The gel can mask the extent of damage and continued use of a damaged fiber can trans fer damage to the instrument.

• When inserting a fiber-optic c able into a connector, gently insert it in as straight a line as possible. Tipping and inserting at an angle can scrape material off the inside of the connector or even break the inside sleeve of connectors made with ceramic material.

• When inserting a fiber-optic connector into a connector, make sure that the fiber end does not touch the outside of the mating connec tor or adapter.

• Avoid over tightening connections. Unlike common electrical connections, tighte r is not better. The purpose of

the connector is to bring two fiber ends together. Once they touch, tightening only causes a greater force to be applied to the delicate fibers. With connectors that have a convex fiber end, the end can be pushed off-axis resulting in misalignmen t a nd e xc essive return lo ss. Many measurements are actuall y improved by backing off the connector pressure. Also, if a piece o f grit does happen to get by the cleaning procedure, the tighter connection is more likely to damage the glass. Tighten the connectors just until the two fibers to uch.

• Keep connectors covered when not in use.

• Use fusion splices on the more permanent critical nodes. Choose the best con-

nector possible. Replace connecting cables regularly. Frequently measure the return loss of the connector to check for degradation, and clean every connector, every time.

All connectors should be treated like the high-quality lens of a good camera. The weak link in instrument and syste m reliability is often the inappropriate use and care of the connector. Because current connectors are so easy to use, there tends to be reduced vigilance in connector care and cleaning. It takes only one missed cle a ning for a piece of grit to perm a nently damage the glass and ruin the conne c to r.

2-38

Getting Started

Accurate Measu rem e nts

Measuring insertion loss and return loss

Consistent measurements with your lightwave equipme nt are a good indication that you have good connections. Since return loss and insertion loss are key factors in determining optical connector performance they can be used to determine connector degradation. A smooth, polished fiber end should produce a good return- l o ss measurement. The qual ity of the polish estab lishes the difference bet w een the “PC” (physical contact) and the “Super PC” connectors. Most connectors today are physical contact which make glass-to-glass connections, therefore it is critical that the area around the glass core be clean and free of scratches. Altho ug h the major area of a connector, excluding the glass, may show scra tc hes and wear, if the glass has maintai n e d its polished smoothness, the connector can st ill provide a good low level return loss co nnection.

If you test your cables and acces so ries for insertion loss and re tur n loss upon receipt, and retain the measured data for comparison, you will be able to tell in the future if any degradation has occurred. Typical values are less than 0.5 dB of loss, and somet im es as little as 0.1 dB of loss with high performa nc e co nnectors. Return loss is a measure of reflection: the le ss reflection the better (the larger the return loss, the smaller the reflection). The best physically contacting connectors have return losses better than 50 dB, although 30 to 40 dB is more common.

To Test Insertion Loss

Use an appropriate lightwave source and a compatible lightwave receiver to test insertion loss. Examples of test equipment configurations include the following equipment:

• 71450A or 71451A Optical Spectrum Analyzers with Option 002 built-in white light source.

• 8702 or 8703 Lightwave Component Analyzer system.

• 83420 Chromatic Dispersion Test Set with an 8510 Network Analyzer.

• 8153 Lightwave Multimeter with a source and power se ns or module.

To Test Return Loss

Use an appropriate lightwave source, lightwave receiver, and lightwave coupler to test return loss. Examples of test equipment configurations include the following equipm ent:

• Agilent 8703 Lightwave Component Analyzer.

• Agilent 8702 Lightwave Component Analyzer with the appropriate source,

receiver, and lightwave coupler.

• Agilent 8504 Precision Reflectometer.

• Agilent 8153 Lightwave Multimeter with a source and power sensor module in

2-39

Getting Started

Accurate Measurements

conjunction with a lightwave coupler.

• Agilent 81554SM Dual Source and Agilent 81534A Return Loss Module.

Visual inspection of fiber ends

Visual inspection of fiber ends can be helpful. Contamination or imperfections on the cable end face can be detected as well as cracks or chips in the fiber itself. Use a microscope (100X to 200X magni fi cati on) to in spect the entire end face for contam ina tion, raised meta l , or dents in the metal as we ll as any other imperfections. Inspect the fiber for cracks and chips. Visible imperfections not touching the fibe r cor e m ay no t affe ct pe rformance (unless the imperfections keep the fibers from contacting).

WARNI NG Always remove both ends of fiber-optic cables from any instrument,

system, or device before visually inspecting the fiber ends. Disable all optical sources before disconnecting fiber-optic cables. Failure to do so may result in permanent injury to your eyes.

Cleaning Connectors

The procedures in this section provide the proper steps for cleaning fiberoptic cables and Agilent univers a l a da p ters. The initial cl ea ning, using the alcohol as a solvent, gently removes any grit and oil. If a caked-on layer of material is still present, (this can happen if the beryllium-copper sides of the ferrule retainer get scraped and deposited on the end of the fiber during insertion of the cable), a second cleaning should be performed. It is not uncommon for a cable or connector to require more than one cleaning.

CAUTION Agilent strongly recommends that index matching compounds not be applied

to their instruments and accessories. Some compounds, such as gels, may be difficult to remove and can contain damaging particulates. If you think the use of such compounds is necessary, refer to the compound manufacturer for information on applica tion and cleaning procedure s.

2-40

Accurate Measu rem e nts

Table 2-3. Cleaning Accessories

Item Agilent Part Number

Pure isopropyl alcohol — Cotton swabs 8520-0023 Small foam swabs 9300-1223 Compressed dust remover (non-residue) 8500-5262

Table 2-4. Dust Caps Provided with Lightwave Inst rume nts

Item Agilent Part Number

Laser shutter cap 08145-64521 FC/PC dust cap 08154-44102

Getting Started

Biconic dust cap 08154-44105 DIN dust cap 5040-9364 HMS10/Agilent dust cap 5040-9361 ST dust cap 5040-9366

To clean a non-lensed connector

CAUTION Do not use any type of foam swab to clean optical fiber ends. Foam swabs can

leave filmy deposits on fiber e nds that can degrade performance.

1 Apply pure isoprop yl alcoh ol to a clean lint-free cotton swab or len s pape r.

Cotton swabs can be used as long as no cotton fibers remain on the fiber end after cleaning.

2 Clean the ferrules and o the r parts of the connector while avoidi ng the end of

the fiber.

3 Apply isopropyl alcohol to a new clean lint-free cotton swab or lens paper. 4 Clean the fiber end with the swab or lens paper.

2-41

Getting Started

Accurate Measurements

Do not scrub during this initial cleaning because grit ca n be caught in the swab and become a gouging element.

5 Immediately dry the fiber end with a clean, dry, lint-free cotton swab or lens

paper.

6 Blow across the connector end face from a distance of 6 to 8 inches using

filtered, dry, compressed air. Aim the compressed air at a shallow angle to the fiber end face.

Nitrogen gas or compressed dust remover can also be us ed.

CAUTION Do not shake, tip, or invert compressed air canisters, because this releases

particles in the can into the air. Refer to instructions provided on the compressed air canister.

Caring for Electrical Connections

The following list includes the basic principles of microwave connector care. For more information on microwave connectors and connector car e, consu lt the Connector Care Manual, part number 08510-90064.

Handling and Storage

• Keep connectors clean

• Extend sleeve or connector nut

• Use plastic endcaps during storage

• Do not touch mating plane surfaces

• Do not set connectors contact-end down

Visual Inspection

• Inspect all connectors carefully before every connection

• Look for metal particles, scratches, and dents

• Do not use damaged connectors

Cleaning

• Try cleaning with compressed air first

• Clean the connector th re ads

• Do not use abrasives

• Do not get liquid onto the plastic support beads

2-42

Making Connections

• Align connectors carefully

• Make preliminary connection lightly

• To tighten, turn connector nut only

• Do not apply bending force to connection

• Do not overtighten prelimi nary connection

• Do not twist or scr ew in connectors

• Do not tighten past the “break” point of the torque wrenc h

Getting Started

Accurate Measu rem e nts

2-43

Getting Started

Electrostatic Discharge Informa tio n

Electrostatic Discharge Information

Electrostatic dis c h a rge (ESD) can damage or destro y electronic components. All work on electronic assemblies should be performed at a static-safe work station. The following figure shows an example of a static-safe work station using two types of ESD protecti on:

• Conductive table-mat and wrist-strap combination.

NOTE For the 86030A 50 GHz LCA system, the static strap is attached to the 86032A

front panel grounding receptacle. Refer to “Front Panel Features” on page 2-8.

• Conductive floor-mat and heel-strap combination.

2-44

Getting Started

Electrostatic Discharge Information

Both types, when used together, provide a significant level of ESD protection. Of the two, only the table-mat and wrist-strap combination provides adequate ESD protection when used alone.

T o ensure user safety, the static-safe accessories must provide at least 1 MΩ of isolation from ground. Refer to Table 17 on page 2-46 for information on ordering static-safe accessories.

2-45

Getting Started

Electrostatic Discharge Informa tio n

WARNI NG These techniques for a static-safe work station should not be used

when working on circuitry with a voltage potential greater th an 500 volts.

Reducing ESD Damage

The following suggestions ma y he lp reduce ESD damag e t ha t o cc urs during testing and servic ing operations.

• Personnel should be grounded with a resistor-isolated wrist strap before removing any assembly from the unit.

• Be sure all instrument s are properly earth-grounde d to prevent a buildup of static charge.

Table 17. Static-Safe Accessories

Agilent Part Number

9300-0797

9300-0980 Wrist-strap cord 1.5 m (5 ft.) 9300-1383 Wrist-strap, color black, stai nless steel, without cord, has four adjustable

9300-1169 ESD heel-strap (reusable 6 to 12 months).

Description

Set includes: 3M static control mat 0.6 m ft.) ground wire. (The wrist-strap and wrist-strap cord are not included. They must be ordered separately.)

links and a 7 mm post-type connection.

× 1.2 m (2 ft. × 4 ft.) and 4.6 cm (15

2-46

Getting Started

Quick Start

This procedure steps y ou through the process of maki ng your first measurement. The verification kit supplied with your system contains a photo detector, which we will use to make an optical-to electrical (O/E) bandwidth response measureme nt.

Photodiode responsivity (amps/watt) refers to how a change in optical powe r is converted to a change in output electrical current. As the frequency of modulation increases, eventually the receiver responsivity will rolloff. Thus, the device has a limited modulation bandwidth. The measurement of modulation bandwidth consists of stim ulating the photodiode with a source of modulated light and measuring the output response current with an electrical receiver. The frequency of the modulation is swept to al low examination of the p ho todiode over a wide range of modulation frequencies.

1 From the Windows Start menu on the 86030A computer, select Programs,

Agilent, 86030A Main to open the software.

NOTE Do NOT attempt to close the analyzer appl i cation until the 86030A system

status window says “System Ready .”

2 Follow the instructions for the La ser power prompt, then press OK.

2-47

Getting Started

Quick Start

3 When the software is first opened, a modulator auto-bias will automatically be

performed, which takes approximately 2 minutes. The m odulator is automatically biased to the optimum (quadrature) performance condition.

An auto-bias does not need to be performed before each individual measurement but should be performed for any of the following conditions:

• at least once every eight hours

• if the temperature has drifted more than 3°C from the user calibration tem-

perature

• if the jumper between the 86032A LASER OUTPUT and LASER INPUT has

been removed and replaced. This routine takes approx im ately two minutes and the re sul ts will be displayed on the screen. Refer to “Auto Bias” on page 2-20.

2-48

Getting Started

Quick Start

4 When the auto bias is finished, click OK to close the Modulator Auto Bias

window. The system has finished setup procedures .

2-49

Getting Started

Quick Start

Making an Optical to Electrical Measurement

1 In the System Modes area, click on O/E (the default m ode ) to se t up for an

optical to electrical measurement.

2 In the Measurement Types area, click on BandWidth. 3 In the Control Options area, click on To Se tup, New User Cal. 4 The message, “Set 8510 to desired Start Frequency, Stop Freq uency, and the

Number of Points” appears. To do this: a On the 8510 analyzer under th e STIMULUS a rea, set t he Start freq uency and

the Stop Frequency to the frequency range required for your measurem ent.

b From the STIMULUS MENU, select NUMBER of POINTS, then 801. c From the RESPONSE MENU, select AVERAGING ON and set to 128 points.

5 Click OK in the application message box.

2-50

Getting Started

Quick Start

6 Follow the onscreen instructions to configure the test set for calibration, then

press OK.

7 In the Control Options area, click on Resp-Isol to perform a response plus

isolation calibration.

8 Follow the on-screen instructions for the Response portion of the calibration

procedure.

9 Follow the on-screen instructions for the Isolation portion of the calibration

procedure. The system first t ak e s a n uncorrected measur em e n t of the internal O/E co n-

verter in the 86032A test set. This raw data along with factory calibration data for the internal O/E are use d to cons truct a calibration file for the sys tem.

Y ou can monitor the System Status area as the calibration is in progress. Once the calibration is completed, you can view the calibration results in the Calibration Information area.

You are now ready to make a bandwidth response measurement.

10 Follow the on-screen instructions for the measurem ent setup. 11 From the 8510 RESPONSE menu, adjust the scale to best fit the trace on the

screen.

a Select REF VALUE and use the kn ob to center t he trace arou nd the display line. b Select SCALE and decrease the dB/div to expand the trace across the display

(approximately 2 dB/div).

c Repeat steps a and b to get th e best view. 12 Select the RESP ONSE MENU key, then SM OOTHING ON. 13 Save the trace data to an Excel file by selecting File, Save Data, Excel File, then,

Form Log Mag. 14 In the Save to Excel dialog box, enter quick_start as the trace file name

then click OK.

You can now view the trace by selecting File, Graph Excel Data, Form Log Mag and

then Open the Quick_Start file. Alternately, you can open a session of Excel

and view or manipula te the trace file from there.

Or, you can further analyze the trace data by using the cont rol s on th e 851 0C.

2-51

Getting Started

Quick Start

2-52

The Calibrati o ns 3-2

Saving and Reusing 86030A Calibration Sets 3-5

O/O Response and Isola tion Bandwid th Calibration 3-8

O/E Response and Isolation Bandwidth Calibration 3-11

O/E Response a nd Match Bandwid th Calibrati on 3-14

E/O Response and Isolation Bandwidth Calibration 3-23

Agilent 86030A System Example Measurements 3-28

Electrical Mismatch Ripple and its Effects on Measure m e nts 3-29

Magnitude Response and Deviation From Linear Phase of a Lightwave

Receiver 3-41

O/E RF Overload Detection Measurement 3-51

Measurement Techniques

The Calibrations

The 86030A software can perform m any diff er ent types of calibrations depending on your device ty pe and measurement needs. Fo l lowing is a list of all of the available calibrations.

• O/O

• Bandwidth Measurement Response Response/Isolation

• Reflection Measurement Response Response/Isolation

• O/E

• Bandwidth Response Response/Isolation Response/Match

• Reflection Response Response/Isolation

• Bandwidth & Reflection Response Response/Isolation

• E/O

• Bandwidth Response Response/Isolation

• Reflection Response

• Bandwidth & Reflection Response Response/Isolation

• Reflection Sensitivi ty Response

• E/E

Use the 8510C for electrical calibrations and me asurements.

3-2

Table 3-1. Purpose and Use of Different Calibration Procedures

Measurement Techniques

The Calibrat ions

Calibration Procedure

Response Transmission or reflection measurement

Response & Isolation

S11 1-port Reflection of any one-port devi ce or well

S22 1-port Reflection of any one-port devi ce or well

Full 2-port Transmission or reflection measurements of

Response Transmission or reflection measurement

Response & Isolation

Response Transmission measurement Frequency response Optical and/or electrical

Response & Isolation

Response & Match

Corresponding Measurement Errors Removed Standard Procedure

Electrical

Frequency response Thru for transmission, open

when the highest accuracy is not required. Transmission of high insertion loss devices or

reflection of high return loss devices. Not as accurate as 1-port or 2-por t ca libration.

terminated two-port devi ce.

highest accuracy for two-port dev ices.

Optical (O, O/O)

when the highest accuracy is not required.

Transmission of high insertion loss devices or reflection of high return loss devices.

Optical (O/E)

Transmission of high Insertio n loss devices Frequency response plus

Transmission measurement for devices wi th large electrical reflectivity.

Frequency response plus isolation in transmissio n or directivity in reflection.

Directivity, source match, frequency response

Directivity, source match, load match, isolation, frequency response, each in forward and reverse directions.

Frequency response Optical thru for

Frequency response, plus isolation in transmissio n or directivity in reflection.

isolation

Frequency response plus electrical mismatch

or short for reflection. Same as response plus

isolation std (load).

Short, open, and load(s).

Short, open, and load(s). Two loads needed for isolation.

transmission, Fresnel or Reflector for reflection.

Same as response plus disconnect cable or turn off laser.

thrus. Same as Response plus

disconnect cable or turn off laser.

Same as Response plus short, opens, and loads.

3-3

Measurement Techniques

The Calibrations

Table 3-1. Purpose and Use of Different C al ibration Procedures

Calibration Procedure

Response Transmission or reflection measur ements. Frequency response Optical and /or electrical

Response and Isolation

Corresponding Measurement Errors Removed Standard Procedure

Optical (E/O)

thrus for transmission, optical load for reflectio n sensitivity.

Transmission of high insertio n loss devices. Frequency response plus

isolation

Note: If cables, connectors, or adapters are removed from the measurement setup that were

used in the calibration, their effect must be accounted for by adding a port extension equivalent to the electrical length of the missing component(s).

Same as response plus disconnect the cable or turn off the laser.

Measurement Error Correction for Devi ces with V Connectors (1.85 mm)

To accurately measure devices with V connectors (1.8 5 mm), adapt the 2. 4 mm electrical cables that are part of the 86030A system, to a 1.85 mm connector. Then perform a measurement calibration on the 86030A sy stem with an 85058 D (1.85 mm) calibration kit. This process will remove the effects of the small reflections from the 2.41/1.85 mm interface.

3-4

Measurement Techniques

Saving and Reusing 86030A Calibration Sets

After you have performed a measurement calibration, the 86030A creates a calibration set that is applied to the measurement, reducing systematic errors. To save time with la ter measurement s, you may want to use a previously created calibration set rather than creating a ne w set.

The 86030A uses the 8510 calibration set registers 1, 2, and 3 to create new calibration sets. If you perform another measurement calibration, the previous calibration set would be overwritten. Therefore, if you want to reuse a calibration set, you mus t m o v e it out of calibration set registers 1 - 3 by do ing one of the following:

• Move the calibration set to 8510 calibration set register 4, 5, 6, 7, or 8.

• Store the calibration set to a floppy disk.

Each calibration set is calculated based on a particular measurement state. Therefore, the error reduction and resulting measurement accuracy from a calibration is o nly valid if you use the sa m e m easurement settings that were used to create the calibration set.

There are also other variables that can affect measurement accuracy when you are reusing calibration sets:

• Differences in the ambient temperature between when you pe rformed the

measurement calibration and when you measured the device unde r te st .

• Differences in the test port cables and accessories you used in the measure-

ment calibration and in the device measurements.

To Save and Reuse Calibration Sets

To save time, you may want to save and reuse a calibration set. Follow thes e general steps:

1 Either move the calibration set to 8510 calibrati on se t registers (4-8) or store

the set to a floppy disk.

2 Save the measurement settings as an instrument state.

3-5

Move or Store a Calibration Set

Measurement Techniques

Saving and Reusing 86030A Calibration Sets

3 Reload and/or recall the calibration set and measurement settings.

1 To move the calibration set from 8510 calibration set registers (1-3) to

calibration se t registers (4-8): a Make sure the calibration set is enabled on the 8510 by pressing CAL, COR-

RECTION ON, and press CAL SET (1-3).

b Press CAL, MORE, MODIFY CALSET, FREQUENCY SUBSET, CREATE &

SAVE, CAL SET (4-8).

c Repeat this step if you want to save more than one calibration set. For ex-

ample, if you have performed a response and match calibration, there would be a calibration set in CAL SET 1 and CAL SET 2.

2 To store a calibration set to a floppy dis k:

a On the 8510, press DISC, STORE, CAL SET 1-8, and select the calibration

set that you want to store. If you want to store all of the calibration sets, select CALSET ALL.

Save the Measurement Settings as an Instrument State

Recall the Calibration Set and Measurement Settings

b Press STORE FILE.

3 Press SAVE, INST STATE (1-7) to save the measurement settings in an

instrument state register.

4 If you want to store the instrument state on a floppy disk, press DISC, STORE,

INST STATE 1-8, the n se lect the state that you wa nt to store.

5 To recall the measurement settings and the associated calibration set from the

8510 registers: a Press RECALL, INST STATE 1-7 and se lec t th e instrument state you want

to recall.

3-6

Measurement Techniques

Saving and Reusing 86030A Calibration Sets

b Press CAL, CAL SET and select the calibration state that you want to recall.

6 To load the measurement settings and the associated calibration set files from

a floppy disk and recall them to the 8510: a Press DISC, LOAD, INST STATE 1-8, then select the state that you want to

load.

b Press RECALL, INST STAT E 1 - 7 an d select the instrument state you want

to recall.

c Press DISK, LOAD, CAL SET 1-7 , then select the set that you want to load. d Press CAL, CAL SET 1-8 and select the calibration state that you want to re-

call.

NOTE If you are recalling calibration sets for a response and match calibration, you

must return the sets to CAL SET 1, and CAL SET 2. The analyzer will apply the calibration sets from those two registers for error correction of a response and match measurement.

3-7

Measurement Techniques

O/O Response and I s ol ation Bandwidth Cal ibration

O/O Response and Isolation Bandwidth Calibration

The following pr o cedure shows you how to mak e a res p on s e and isolation bandwidth calibration.

1 In the System Modes area in the Setup Screen, click on O/O to setup for an

optical to optical measurement.

2 In the Measurement Types area, click on BandWidth. 3 In the Control Options area, click on New User Cal. 4 The message, “Set 8510 to desired Start Frequency, Stop Freq ue ncy,

Averaging, and the Number of Points” appears. To do this: a On the 8510 analyzer under th e STIMULUS a rea, set t he Start freq uency and

the Stop Frequency to the frequency range required for your measurem ent.

b From the STIMULUS MENU, select NUMBER of POINTS, then select the number

of data points, for exa m ple, 801 points.

c From the RESPONSE MENU, select A VERAGING ON/restart, then enter the

number of averages. For example, for 128 averages enter 128 x1.

5 In the Control Options area, click on Resp-Isol to perform a response plus

isolation calibration.

6 Follow the on-screen instructions to complete the calibration procedure.

3-8

Measurement Techniques

O/O Response and Isolatio n Bandwidth Calibration

3-9

Measurement Techniques

O/O Response and I s ol ation Bandwidth Cal ibration

The figure below shows the results of an optical to optical measurement of a through line with 0 dB loss. The magnitude of the trace (that is, the vertical axis) is measured in dBo. For more information, refe r to “O/O Display Scaling

Calculations” on page 5-18.

Figure 3-1. Measurement results of a through line

3-10

Measurement Techniques

O/E Response and Is olation Bandwidth Calibr a tio n

O/E Response and Isolation Bandwidth Calibration

The following pr o c e dure shows you how to make an Optical to Electr i c a l response and isolation bandwidth calibration.

1 In the System Modes area in the Setup Screen, click on O/E to setup for an

optical to electrical measurement.

2 In the Measurement Types area, click on BandWidth. 3 In the Control Options area, click on New User Cal. 4 The message, “Set 8510 to desired Start Frequency, Stop Freque ncy ,

Averaging, and the Number of Points” appears. To do this: a On the 8510 analyzer under th e STIMULUS a rea, set t he Start freq uency and

the Stop Frequency to the frequency range required for yo ur measurement.

b From the STIMULUS MENU, select NUMBER of POINTS, then select the number

of data points, for exa m ple, 801 points.

c From the RESPONSE ME N U , select AVERAGING ON/restart, then enter the

number of averages. For example, for 128 averages enter 128 x1.

5 In the Control Options area, click on Resp-Isol to perform a response plus

isolation calibration.

3-11

Measurement Techniques

O/E Response and Iso lation Bandwidth Calibr at i on

6 Follow the on-screen instructions for the response portion of the calibration

procedure. See figure below.

3-12

Measurement Techniques

O/E Response and Is olation Bandwidth Calibr a tio n

7 Follow the on-screen instructions for the isolation portion of the calibration

procedure. See figure belo w.

3-13

Measurement Techniques

O/E Response and Ma tch Bandwidth Calibrati on

O/E Response and Match Bandwidth Calibration

The 86030A is capable of reducing the mismatch measurement uncertainty of a device under test by utilizing a response and match calibration. The advantage of a response and match calibration is that it compensates for the mismatch of the device under test, providing a more accurate cal ibration and measurement. Significant reduction of ele ctri cal mismat ch er ror resul ts.

For this calibration, you will need to use some of the accessories supp li e d in the 85056A 2.4 mm Calibration Kit.

The following pr o c e dure shows you how to make an Optical to Electr i c a l response and match bandwidth calibration.

1 In the System Modes area in the Setup Screen, click on O/E to setup for an

optical to electrical measurement.

2 In the Measurement Types area, click on BandWidth. 3 In the Control Options area, click on New User Cal. 4 The message, “Set 8510 to desired Start Frequency, Stop Freq ue ncy,

Averaging, and the Number of Points” appears. To do this: a On the 8510 analyzer under th e STIMULUS a rea, set t he Start freq uency and

the Stop Frequency to the frequency range required for your measurem ent.

b From the STIMULUS MENU, select NUMBER of POINTS, then select the number

of data points, for exa m ple, 801 points.

c From the RESPONSE MENU, select A VERAGING ON/restart, then enter the

number of averages. For example, for 128 averages enter 128 x1.

3-14

Measurement Techniques

O/E Response and Match Bandwidth Calibration

5 When the following message appears, click OK to continue.

6 In the Control Opt ions area, click on Resp-Match to perform a response plus

impedance match calibration.

3-15

Measurement Techniques

O/E Response and Ma tch Bandwidth Calibrati on

One-Port Calibration on Port 2

7 Connect the equipment as shown on-screen, choosing an Open to connect to

the end of the 8517B Port 2 cable.

8 From the 8510C function keys, press Open.

3-16

Measurement Techniques

O/E Response and Match Bandwidth Calibration

Once a sweep of the trace is completed, the message “Connect STD then press key to Measure” appears, and you will notice that the Open func ti on

key on the 8510C is now underlined. This indicates that the Open portion of the calibration process is completed and you are ready to continue with a Short.

9 Connect the equipment as shown on the screen, choosing a Short to connect to

the end of the 8517B Port 1 cable.

10 From the 8510C function keys, press Short.

Once a sweep of the trace is completed, the message “Connect STD then press key to Measure” appears, and you will notice that the Short funct ion key on the 8510C is now underlined. This indi c a te s that the Short portio n of the calibration process is completed and you are ready to continue with a Load.

11 Connect the equipment as shown onscreen, choosing a 50 ohm load to connect

to the end of the 8517B Port 1 cable.

12 From the 8510C function keys, press Loads then Broadband.

Once a sweep of the trace is completed, you will notice that the Broadband function key on the 8510C is now underlin ed. Thi s i ndi cate s that the Load Broadband portion of the calibration process is completed.

13 From the 8510C function keys, press Done Loads. 14 From the 8510C function keys, press Save 1-Port Cal.

NOTE When the 8510C message “Select Calibration Set” appears, do not select a cal

set to save. This completes the Port 2 portion of the match calibration.

15 From the 86030A software, click OK to continue with th e Por t 1 porti on of th e

match calibration.

3-17

Measurement Techniques

O/E Response and Ma tch Bandwidth Calibrati on

One-Port Calibration on Port 1

16 Repeat Step 7 through Step 15 by attaching the Open, Short, and Load to the

8517B Port 2 instead of Port 1. Refer to Figure 3-2.

Figure 3-2.

3-18

Measurement Techniques

O/E Response and Match Bandwidth Calibration

Measurement of Port 1 Reflectivity

17 Connect the equipment as shown in Figure 3-3 then click OK.

Figure 3-3.

3-19

Measurement Techniques

O/E Response and Ma tch Bandwidth Calibrati on

Measurement of 86030A Internal O/E Response

18 Connect the equipment as shown in Figure 3-4 then click OK.

Figure 3-4.

3-20

Measurement Techniques

O/E Response and Match Bandwidth Calibration

Measurement of Device Under Test

19 Connect the equipment as shown in Figure 3-5 then click OK.

Figure 3-5.

Once the calibra tion is completed, the results will be displayed in the User Calibration Information area.

3-21

Measurement Techniques

O/E Response and Ma tch Bandwidth Calibrati on

New Device Under Test (DUT)

The disadvantages of a response plus match calibration is that it is a more complicated and lengthy procedure and it is only valid for a part icular DUT.

Using the New Dut function, in the Control Options area, repeats only the DUT reflecti vity p ortio n of the c alibrat ion. T his greatl y redu ces t he ca librat ion time when a measurement of a new test device is desired, or if the electrical port match has changed.

The 86030A also provides a capability to mathematically reduce the effects of electrical mismatch. In order to do this, the DUT response information is modified using meas urem en ts of the el ect ric al re fl ect ivi ty of the DUT and th e el ectrical reflectivity of the 86030A. Significant reducti on of e le ctrical mismatch error results.

3-22

Measurement Techniques

E/O Response and Is ola tio n Ba ndwidth Calibration

E/O Response and Isolation Bandwidth Calibration

The procedure below shows you how to make an Electrical to Op ti cal response and isolation bandwidth calibration.

E/O Measurement Considerations:

• Modulator me a surements requir e an external polariza tion controller connected in the test setup. However, the outputof the 86030A is keyed to the slow axis of PMF (polarizat io n ma in taining fiber), and if th e mod u la tor under test is similarly keyed and PMF is used from the laser output to the input of the modulator, the polarization controller may be eliminated. Otherwise setup the equipment as follows and shown in Figure 3-6 on page 3-26:

• Connect the 86030A LASER OUTPUT to the polarization controller.

• Connect the polarization controller to the modulator (DUT) input.

• Connect the modulator (DUT) output to the 86030A OPTICAL RECEIVER

INPUT.

• Connect the 86030A RF OUTPUT through a bias tee (if needed) to the mod-

ulator (DUT) RF input.

• Adjust the bias and the polarization controller for maximum output, as seen

on the analyzer screen.

• Modulator measurement response is dependent on both the RF drive level and the amplitude of th e signal at the modula to r output. To make compari so n s between modulators, both signal levels should be controlled.

• Set the RF drive level and the optical power at the modulator (DUT) output

to 1 mW.

• The RF drive lev e l to the modulator (DUT) should be ±0.5 m W a c ross the

band. If the drive varies more than ±0.5 mW, try shortening the RF cable or making a series of measurements over smaller ranges.

1 In the System Modes area in the Setup Screen, click on E/O to setup for an

electrical to optical measurement.

2 In the Measurement Types area, click on BandWidth. 3 In the Control Options area, click on New User Cal. 4 The message, “Set 8510 to desired Start Frequency, Stop Freque ncy ,

3-23

Measurement Techniques

E/O Response and Isolation Bandwidth Calibration

Averaging, and the Number of Points” appears. To do this: a On the 8510 analyzer under the STI MULUS area, set the Start frequency to

and the Stop Frequency to the frequency rang e required for your me a surement.

b From the STIMULUS MENU, select NUMBER of POINTS, then select the number

of data points, for exa m ple, 801 points.

c From the RESPONSE MENU, select A VERAGING ON/restart, then enter the

number of averages. For example, for 128 averages enter 128 x1.

5 In the Control Options area, click on Resp-Isol to perform a response plus

isolation calibration.

6 Follow the on-screen instructions to perform the Response portion of the

calibration pr oc edure. See figure be lo w.

3-24

Measurement Techniques

E/O Response and Is ola tio n Ba ndwidth Calibration

7 Follow the on-screen instructions to perform the Isolation portion of the

calibration pro c e d ure. See figure belo w.

3-25

Measurement Techniques

E/O Response and Isolation Bandwidth Calibration

8 The calibration is complete. Connect the E/O device under test. For exam ple,

the figure below shows the te st setup for a modulator measurem e n t.

Figure 3-6. Setup for a Modulator Measurement

3-26

Agilent 86032A User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Installation

Installation

Step 1. Prepare the Site

Step 2. Install the Monitor Mount Assembly

Step 3. Install the Keybo a r d/M ouse Transmitter and the Work Surface

Step 4. Confirm Front and Rear Panel Connections

Step 5. Turn the System On

Step 6. Configure for Remote Operation

Getting Started

Configuration Option s

Front Panel Features

Rear Panel Features

Software Overview

File Menu

Options Menu

Tools Menu

Laser Safety Co nsiderations

Accurate Measu rem e nts

Electrostatic Discharge Informa tio n

Quick Start

Measurement Techniques

The Calibrations

Saving and Reusing 86030A Calibration Sets

O/O Response and I s ol ation Bandwidth Cal ibration

O/E Response and Is olation Bandwidth Calibr a tio n

O/E Response and Ma tch Bandwidth Calibrati on

E/O Response and Is ola tio n Ba ndwidth Calibration