Texas Instruments TRF1500 User Manual

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Evaluation Board Documentation

TRF1500 Integrated Dual-Band RF Receiver User’s Guide

APPLICATION BRIEF: SWRA004A

Wireless Communications Business Unit

Digital Signal Processing Solutions July 98

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Contents

Abstract.........................................................................................................................9

Product Support .........................................................................................................10

The TI Advantage Extends Beyond RF to Every Other Major Wireless System

Block.......................................................................................................................10

Related Documentation...........................................................................................11

World Wide Web.....................................................................................................11

Email.......................................................................................................................11

Introducti on.................................................................................................................12

Design Considerations...............................................................................................13

External Components..............................................................................................13

Board Design and Impedance Matching..................................................................13

TRF 1500 Dual-Band Receiver ...................................................................................14

TRF1500 Control State ...............................................................................................17

Low Band Cascaded Receiver Section: LNA, External SAW Filter, Mixer, and LO

Buffer Amplifier...........................................................................................................18

Low-Band LNA........................................................................................................19

Low-Band LNA Turn on Time..................................................................................19

Low-Band LNA Input...............................................................................................20

Low-Band LNA Output............................................................................................20

Surface Acoustic Wave (SAW) Filter.......................................................................21

Low-Band Mixer......................................................................................................22

Low-Band Mixer RF Input .......................................................................................22

Low-Band Mixer LO Input .......................................................................................23

Low-Band IF Output................................................................................................23

Low-Band LO Buffer Amplifier Output.....................................................................24

Low-Band Cascaded Test Guide ...............................................................................26

LOW-Band Cascaded: Power Conversion Gain......................................................26

Low-Band Cascaded: Power Conversion Gain Reduction.......................................27

Low-Band Cascaded: Noise Figure.........................................................................28

Low-Band Cascaded: RF Input Return Loss...........................................................30

Low-Band Cascaded: LO Input Return Loss...........................................................30

LOW BAND: LO Buffer Out pu t Power.....................................................................31

Low-Band: Power Leakage LO In to RF In..............................................................31

Low-Band Cascaded: Third Order Input Intercept Point (IIP3).................................32

Low-Band Cascaded: 1dB RF Input Compression Point.........................................33

Low-Band Cascaded: 1dB Blocking Point...............................................................34

High-Band Cascaded Receiver Section: LNA, Mixer, LO Buffer Amplifier .............35

Cascaded High-Band Receiver Section: LNA, Mixer, and LO Amplifier...................35

High-Band RF Input................................................................................................36

High-Band LO Input................................................................................................36

High-Band IF Output...............................................................................................38

High-Band LO Buffer Amplifier Output ....................................................................39

High-Band Cascaded Test Guide...............................................................................40

High-Band Cascaded: Power Conversion Gain.......................................................40

Contents

High-Band Cascaded: Power Conversion Gain Reduction......................................41

High-Band Cascaded: Image Rejection...................................................................42

High-Band Cascaded: Noise Figure........................................................................43

High-Band Cascaded: RF Input Return Loss ..........................................................44

High-Band : LO Bu ffer Out pu t Power.......................................................................45

High-Band Cascaded: Power Leakage LO In to RF In ............................................46

High-Band Cascaded: Third Order Input Intercept Point (IIP3)................................46

High-Band Cascaded: 1dB Input Compression Point..............................................47

High-Band Cascaded: 2X2 Spur Performance........................................................48

High Band: 3X3 Spur Performance.........................................................................49

Low-Band and High-Band Transmit ..........................................................................50

Low- and High-Band Transmit Mixer.......................................................................50

Low-Band and High-Band Transmit Mixer RF Input ................................................50

Low- and High-Band Transmit Mixer IF Output .......................................................51

Low-Band Transmit Mixer Test Guide.......................................................................52

Low-Band Transmit Mixer: Power Conversion Gain................................................52

Low-Band Transmit Mixer: Noise Figure .................................................................53

Low-Band Transmit Mixer: Input Return Loss..........................................................54

Low-Band Transmit Mixer: Power Leakage LO In to TX In......................................55

Low-Band Transmit Mixer: Power Leakage TX In to LO In......................................55

Low-Band Transmit Mixer: 1dB Input Compression Point .......................................56

Low-Band Transmit Mixer: Second Order Input Intercept Point (IIP2).....................57

Low-Band Transmit Mixer: Third Order Input Intercept Point (IIP3).........................58

High-Band Transmit Mixer Test Guide......................................................................59

Low-Band LNA Stand-Alone Test Guide...................................................................60

Low-Band LNA: Gain ..............................................................................................60

Low-Band LNA: Input Return Loss..........................................................................60

Low-Band LNA: Output Return Loss.......................................................................61

Low-Band LNA: Isolation.........................................................................................61

Low-Band LNA: 1dB Input Compression Point ........................................................61

Low-Band LNA: Noise Figure..................................................................................62

Low-Band LNA: Third Order Input Intercept Point (IIP3)..........................................63

Low-Band Receiver Mixer Stand-Alone Test Guide .................................................65

Low-Band Receiver Mixer: Power Conversion Gain................................................65

Low-Band Receiver Mixer: Input Return Loss.........................................................66

Low-Band Receiver Mixer: Power Leakage LO In to RF In......................................67

Low-Band Receiver Mixer: Noise Figure.................................................................67

Low-Band Receiver Mixer: 1dB RF Input Compression Point..................................69

Low-Band Receiver Mixer: Third Order Input Intercept Point (IIP3).........................70

Appendix A: Test Bench Configuration.....................................................................72

Figures

Figure 1. TRF1500 Dual-Band Receiver Block Diagram................................................14

Figure 2. Cascaded Block Diagram of the Low-Band Receiver Section.........................18

Figure 3. Voltage Divider at Low-Band LNA Input..........................................................19

Figure 4. Low- Ba nd LN A In pu t Co n figur ation...................................................................20

Figure 5. Low- Ba nd LN A Ou tp ut C onfi gur a ti o n.................................................................21

Figure 6. SA W Filter Inserti o n Loss..................................................................................21

Figure 7. Low-Band Mixer RF Input Configuration ............................................................22

Figure 8. Low-Band Mixer LO Input Configuration............................................................23

Figure 9. Low-Band IF Output Configuration....................................................................24

Figure 10. Low-Band Buffer Amplifier Output Configuration .............................................25

Figure 11. Block Diagram of the High-Band Receiver Section..........................................35

Figure 12. High-Band RF Input Configuration...................................................................36

Figure 13. High-Band LO Frequency Doubler Driven Configuration .................................37

Figure 14. High-Band LO Directly Driven Configuration....................................................37

Figure 15. High-Band IF Output Configuration..................................................................38

Figure 16. High-Band LO Buffer Amplifier Output Configuration.......................................39

Figure 17. Transmit Mixer Block Diagram.........................................................................50

Figure 18. Low- and High-Band Transmit Mixer RF Input Configuration...........................51

Figure 19. Low- and High-Band Transmit Mixer IF Output Configuration..........................51

Figure 20. Test Bench Setup: Power Conversion Gain, Power Conversion Gain

Reduction, 1dB RF Input Compression Point, Second Order Input Intercept Point (IIP2), 2x2 Spur Perform ance, 3x3 Spur Performance, Ima ge rej ec tion

and LO Buffer Output Power...........................................................................72

Figure 21. Test Bench Setup: Third Order Input Intercept Point (IIP3), 1dB Blocking

Point Measurements.......................................................................................72

Figure 22. Test Bench Setup: Noise Figure .....................................................................73

Figure 23. Test Bench Setup: Power Leakage LO In to RF In .........................................73

Figure 24. Test Bench Setup: Power Leakage RF In to LO In Measurements.................74

Figure 25. Test Bench Setup: LNA Noise Figure Measurements .....................................74

Figure 26. Test Bench Setup: LNA Third Order Input Intercept Point (IIP3) Measurement75

Figure 27. Test Bench Setup: LNA 1dB Input Compression Point...................................75

Tables

Table 1. Pin Descriptions.................................................................................................15

Table 2. Control State and the Corresponding Active Circuits.........................................17

Table 3. LB LNA, LB Mixer, SAW Filter, and LB IF Amp Parameters...............................26

Table 4. HB LNA, HB mixer, HB IF amp..........................................................................40

Table 5. Low-Band Transmit Performance Parameters...................................................52

Table 6. High-Band Transmit Mixer Performance Parameters.........................................59

Table 7. Low-Band LNA Parameters...............................................................................60

Table 8. Low-Band Receiver Mixer Parameters..............................................................65

TRF1500 Integrated Dual-Band RF

Abstract

Receiver User’s Guide

The dual-band handset market is expanding very rapidly due to the increase in customers requiring roaming capa bility. The customer also demands that handsets have an increase in features while keeping the size compact. These dual-band handset requirements put pressure on the integrated circuit manufacturer to be innovative while keeping costs low.

To meet this demand, Texas Instruments (TI) has developed the TRF1500 receiver. The TRF1500 is a fully-integrated dual-band receiver in a single package. The selection of the external components and the layout of the system board required to complete a tr ans ceiver des ign are cri ti c al t o achi eve maxim um perform ance.

This application report discusses the implementation and impedance matching of each section of the TRF1500 to keep the required board area to a minimum and minimizing external components while maximizing performance. It also discusses parameter measurement techniques.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 9

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Product Suppor t

The TI Advan ta ge E xt en ds Be yon d RF to E very Other Major Wireless System Block

Speaker

Audio

Interface

Microphone

SINGLE CHIP ANAL OG

BASEBAND

TMS320C54X

DSP Core

S/W

ASIC

TSC6000

SINGLE CHIP DIGIT AL BASE BAND

ARM7TDMIE

BACKPLANE

Microcontroller

ARM7TDMIE

(C470)

S/W

Interface

User Display

Keyboard

SIM Card

Receiver

TRF1xxx

Synthesizer

TRF2xxx

Modulator

Modulator TRF3xxx

TRF3xxx

RF SE CTION

Op Amps

Switches

Regulators

POW E R MGMT

Power A mp

TRF7xxx,

TRF8xxx

Digital Baseband

TI’s single-chip Digital Baseband Platform, combines two high-performance core processors – a digital signal processor tailored for digital wireless applications and a microcontroller designed specifically for low-power embedded systems. The customizable platform helps wireless digital telephone manufacturers lower component counts, save board space, reduce power consumption, introduce new features, save development costs and achieve faster time to market, at the same time giving them flexibility and performance to support any standard worldwide.

Analog Baseband

TI analog baseband components provide a Mixed-signal bridge between the real world of analog si g nal s an d di gi t al sig nal pr ocessors, the key en abli n g t ec hnology of the digital wireless industry. Using a seamless architecture for wireless communications technology, TI matches its baseband interfaces, radio frequency ICs and power managem en t I Cs to digital signal pr ocessing engines t o cre at e complete DSP Solutio ns for digital wireless systems.

Power Management

TI provides power management solutions with integration levels designed to meet the needs of a ran ge o f wireless applicatio ns . From di s cr et e LD Os an d v olt a ge supervisors to complete power supplies for the baseband section, TI power ma nagement solutions play an important role in increasing wireless battery life, time-to-market and system functionality.

For more information visit the Wireless Communications web site at www.ti.com/sc/docs/wireless/home.htm.

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Related Documentation

The following list specifies product names, part numbers, and literature numbers of corresponding TI documentation.

Dual-Band/Dual-Mode PCS Receiver

❑

SLWS041A

World Wide Web

Our World Wide Web site at www.ti.com contains the most up to date product information, revisions, and additions. Users registering with TI&ME can build custom information pages and receive new product updates automatically via email.

For technical issues or clarification on switching products, please send a detailed email to sc-infomaster@ti.com. Questions receive prompt attention and are usually answered within one business day.

, Literature number

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 11

Introduc ti on

SWRA004A

The TRF1500 is a dual-band/dual-mode Personal Communications Syste m (PCS) receiver for cellular telephones operating dual mode (a nalog and digital) in the 800 MHz band and single mode (digital) in the 1900 MHz band. The TRF1500 consists of a low noise amplifier (LNA) and mixer for each band. For image rejection, the low-ba nd receiver relies on an off-chip image rejection filter between the LNA and mixer while the highband receiver uses an image rejection mixer. The device operates from a single 3.75 volt supply and is controlled by six digital CMOS control lines. The digital control offers a wide range of control states, including a sleep mode where the device typically

draws less than 5µA. Additionally, the local o scillator (LO) inputs have buffered outputs

that can be used in either single-ended or differential mode for a phase-locked-loop (PLL) configuration. A state is also available that allows the low-band LO to serve as the high-band LO through a mode-selectable frequency doubler.

A wide-ba nd mix er is als o avai l a bl e for tr ansm i t loo p ar chi t ec t ur es which are commonly used in advanced mobile phone systems, global systems for mobile communications and other digital systems.

The TRF1500 is available in a 48-pin plastic thin quad flatpack package and is characterized for operation from -40C to 85C operatin g fr ee- ai r tem p er ature.

Please refer to the data sheet for the TRF1500 (TI literature number SLWS041A) for detailed information on the device specifications and refer to the users guide for test instructions (TI literature number SWRA004A).

12 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Design Conside ra ti ons

The successful integration of a TRF1500 receiver device into a design is dependent upon the performance of the external components and the quality of the board design and layout.

Ex ternal Componen ts

Componen t tolerance and Q specifications (where applicable) should be obs er ve d dur i n g the selecti o n o f any exte rnal components. The TRF1500 data sheet, TI literature number SLWS041A, includes a Bill of Mate rials (BOM) detailing components with proven performance, that are used on the evaluation board. The location and orientation of components should also be taken into consideration for maximum performance and manufacturability. For e xamp le, the lo w-ba nd imag e rejection is dependent on an external Surface Acoustic Wave (SAW) component. This filter is used to reject signal outside the band of the receiver and has bee n chosen to maximize the TR F1500 performance, while maintaining minimum size and cost.

Board Design and Impedance Matching

The quality of the board layout is also critical to the TRF1500 performance. Co rrect transmission line impedances must be maintained throughout the design to insure maximum performance. Co rrect transmission line impedances can be maintained by using proper line widths and board stack-up in relation to the dielectric constant of the board material.

Utilizing the correct external component to match the device impedance to board transmission line impedance is also very important.

For measurement simplicity, the e valuation board utilizes RF Balun transformers for impedance matching selected differential inputs and outputs to single-ended inpu ts and outputs. Please note that the Baluns are used only for evaluating the device on the evaluation board and do not have to be included in the end user’s application.

To minimize unwanted signal interference and coupling, digital lines should be routed around and away from the receiver. On a multi-layer board, running a separate plane for the digital lines is highly recommended. Power supply lines should be filtered and regulate d as clo se as poss ible at the device term i nal.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 13

TRF 1500 Dual-Band Receiver

A block diagram of the TRF1500 dual-band receiver front end down converter is shown in Figure 1. Pin names and descriptions are provided in Table 1. The device operates from a single 3.75 volt supply and its operation is controlled by 6 digital CMOS control lines the TRF1500 operates in 18 different states. The control codes and the corresponding active circuits are given in Table 2.

Figure 1. TRF1500 Dual-Band Receiver Block Diagram

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14 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Table 1. Pin Descriptions

Pin Number Name Description

1 Bias Adjust Bias adjust 2 TX IF + Transmit IF, noninverting output 3 TX IF - Transmit IF, inv er ting output 4 GND ground 5 MIX IN LOW BAND Low band mixer input 6 GND ground 7VCC Vcc 8 GND Ground

9 TX + Transmit, noninverting input 10 TX - Transmit, inverting input 11 GND Ground 12 IR ADJUST D Image rejection adjustment 13 HI/LO High band/low band select 14 SYN ON VCO power control 15 HIGH BAND IF + High band IF noninvert ing output 16 HIGH BAND IF - High band IF, inver ting output 17 LOW BAND IF + Low band IF noninverting output 18 LOW BAND IF - Low band IF, inverting output 19 GND ground 20 HIGH BAND LO + High band noninverting LO output 21 HIGH BAND LO - High band, inv erti ng LO out put 22 LOW BAND LO + Low band noninverting LO output 23 LOW BAND LO - Low band, inv er ting LO output 24 RX ON Low noise amplifier/mixer power control 25 VCC Vcc 26 TX ON Transmit mixer/driver power control 27 HIGH BAND LO IN -/RF GND High band LO inverting input/RF GND 28 HIGH BAND LO IN + High band LO noninverting input 29 GND ground 30 DOUDLER TANK Doubler output 31 VCC VCC 32 LOW BAND LO IN Low band LO input 33 GND ground 34 GND ground 35 X2 ON Doubler power control 36 IR ADJUST A Image rejection adjustm ent 37 IR ADJUST B Image rejection adjustm ent

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 15

38 STRONG SIGNAL Strong signal indication 39 GND ground 40 VCC VCC 41 GND ground 42 LNA IN HIGH BAND High band LNA input 43 LNA IN LOW BAND Low band LNA input 44 GND ground 45 LNA OUT LOW BAND Low band LNA output 46 GND ground 47 GND ground 48 IR ADJUST C Image rejection adjustment

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16 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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TRF1500 Control State

The TRF1500 operates in 18 different states: The control code and active circuits are given in Table 2.

Table 2. Control State and the Corresponding Active Circuits

Control Code

(HI/LO, SYN ON, RX ON, TX ON, STRONG SIGNAL, X2)

000000 Sleep Mode 010000 Low-Band LO Input Buffer On LB LO Buffer 011000 Low-Band Receive Normal LB LO Buffer, LB LNA, LB Mixer 011010 Low-Band Receive Strong Signal LB LO Buffer, LB Mixer 010100 Low-Band Transmit Mixer LB LO Buffer, LB TX Mixer 011100 Low-Band Receive and Transmit Mixer LB LO Buffer, LB LNA (On High), LB Mixer , LB TX

011110 Low-Band Transmit Mixer LB LO Buffer, LB LNA (On High), LB Mixer 010001 Doubler On LB LO Buffer, Frequency Doubler, HB LO Buffer 011001 Low-Band Receive Normal, Doubler On

011011 Low-Band Receive Strong Signal, DoublerOnLB LO Buffer, LB Mixer, Fr equenc y Doubler

011111 Low-Band Transmit, Doubler On LB LO Buffer, LB LNA (On High), LB Mixer, LB TX

111011 High-Band Receive Strong Signal, DoublerOnHB LO Buffer, HB Mixer, Fr equenc y Doubler

110000 High-Band LO Input B uff er On HB LO Buffer 111000 High-Band Receive Normal HB LO Buffer, HB LNA, HB Mixer 111010 High-Band Receive Strong Signal HB LO Buffer, HB Mixer 111001 High-Band Receive Frequency, Doubler On LB LO Buff er, HB LO Buffer, HB LNA, HB Mixer,

110100 High-Band Transmit Normal HB LO Buffer, HB TX Mixer 110101 High-Band Transmit Frequency, Doubler

Active Circuits

Mixer

LB LO Buffer, LB LNA, LB Mixer, F r equenc y Doubler

Mixer

Frequency Doubler

HB LO Buffer, HB TX Mixer, Frequency Doubler, LB LO Buffer

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 17

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Low Band Cascaded Receiver Section: LNA, External SAW Filter, Mixer, and LO Buffer Ampli f ier

The TRF1500 low-band receiver section, shown in Figure 2, is an integrated front-end down converter designed to operate in the 800 MHz frequency range. The low-band down converter consists of an LNA, mixer, LO buffer amplifier and an off-chip image reject filter. The digital control allows the low-band to operate in thre e different states to compensate for the environment in which the TRF1500 is operating. The device can be operated in the normal state, where the LNA, mixer and buffer amplifier are on, the strong signal state, where the LNA is off and the mixer and buffer amplifier are on, or the transmit state, where the LNA bias current is increased to prevent compression when the transmitter is on.

The low-band receiver has low typical current consumption of 21mA at 3.75V supply. The cascaded gain is typically 26dB while providing good dynamic range with approximately a -10dBm third order input intercept point (IIP3). The low-band receiver has a typical system noise figure of approximately 2.5 dB for excellent sensitivity.

Figure 2. Cascaded Block Diagram of the Low-Band Receiver Section

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Low-B an d LNA

In a typical down-conversion receiver, the LNA is usually placed directly after the antenna and a band-select filter. The purpose of the LNA is to amplify the desired signal being received while adding as little undesired noise and distortion as possible. The TRF1500 LNA is a common emitter amplifier, designed to operate on a single 3.75 volt supply. The LNA has two selectable gain states, normal state or strong signal state, which are controlled with the digital CMOS control lines. The strong signal state, which disables the LNA, is provided for operation in a high signal environment such as near the base station. Operating near the base station in the normal state could cause an increase in the intermodulation product levels and thus cause undesired noise and distortion in the receiver. Stand-alone LNA performance can be ascertained by reconfiguring the evaluation board as noted on the da tashee t.

Low-B an d LNA Turn on Tim e

The turn on time can be adjusted by changing the values of C10, R6 and R7, as shown in Figure 3 and Figure 4. The resistors form a voltage-divider network across the supply, Vcc. The function of this network is to provide a bias condition near the ideal operating region at the base of the common emitter amplifier. By providing this bias condition, the charge time of the series capacitor, C10, can be ad justed. Changing the value of resistors should not affect gain, IIP3 or noise figure (NF) performance.

Figure 3. Voltage Divider at Low-Band LNA Input

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 19

Low-B an d LNA Input

Figure 4 details the lo w-band LNA input configuration. The LNA input impedance matching network primarily determines the cascaded gain, noise figure, and input return loss performance of the low-band receiver section. A simple high-pass shunt-L (L10) impedance matching network is used for optimum noise figure performance. The trade off for this optimization is a lower input return loss in the pass-band, but with sufficient attenuation in the stop-band. C10 has minimal effect on matching and is used mainly to optimize the turn-on time.

Figure 4. Low-Band LNA Input Configuration

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Low-B an d LNA Output

Figure 5 details the LNA output configuration. The LNA output impedance matching network has several functions. The matching network optimizes the third order input intercept point (IIP3) performance while also matching the LNA output impedance to the Surface Acoustic W a ve (SAW) filter input impedance. A shunt-C (C11) is used to match the LNA output to the SAW filter input. Increasing the value of the shunt capacito r will improve the gain and noise f igu re performance but will degrade the third order input intercept point. The end user can adjust the LNA input and output mat chi n g network to optimize a particular parameter of interest.

20 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Figure 5. Low-Band LNA Output Configuration

Surface Aco us tic Wave (SAW) Filter

The SAW filter is used primarily as an image-reject filter (IRF). The i m age frequency (f frequency (f

). The image frequency acts as an interferer to the system.

) plus two times the IF frequ ency (fIF); fIM = fCH + (2 x

During the down-conversion process, the image and the desired channel are both converted to a common IF. Left unfiltered, the image could completely mask the desired signal. The IRF rejects this image before the RF signal is introduced to the mixer.

) is located at the desired channel

By minimizing the image before it reaches the mixer, the sensitivity of the receiver is enhanced. To further minimize potential interferers, a band-select filter is typically used at the front of the receiver, before the LNA. The band-select filter passes only those frequencies that fall within the system receive band. In many TDMA systems, the duplexor acts as the band-select filter.

The off-c hip SAW image- r eject filter used on the TR F1 500 applications board has a 3dB nominal insertion loss and a 25 MHz bandwid th at a c en ter fr eq uency of 880 MHz as shown in Fi gur e 6.

Figure 6. SAW Filter Insertion Loss

SAW Filter Insertion Loss

-5

-10

-15

-20

-25

-30

-35

-40

Insertion Loss (dB)

-45

-50

-55

-60

860

Frequency (M Hz)

900

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 21

Low-Band Mixer

SWRA004A

The purpose of the mixer in a down-conversion receiver is to translate incoming signals from one frequency to another. The low-band mixer in the TRF1500 is a three port high-side injected circuit. The mixer takes two known input signals, a radio frequency (RF) signal and a local oscillator (LO) signal and mixes them together to create a sum and difference intermediate frequency (IF). High-side injection means the LO is higher in frequency than the RF by the IF frequency. The output of the mixer is the IF and contains the difference and the sum of the RF and LO signals.

The difference of the RF and LO signals is the desired IF frequency in a down-conversion receiver. The undesired signal, the sum of the RF and LO frequencies, can be attenuated by using a low pass filter. The low-band mixer section of the TRF1500 is a Gilbert cell design with open collector outputs. The Gilbert cell structure was used for its robust isolation and harmonic suppression characteristics.

The TRF1500 mixer typically achieves a noise figure of 7.5 dB with an input third order intercept point of 3.5 dBm. Stand-alone mixer performance can be ascertained by reconfiguring the evaluati on board as noted on the dat ash eet.

Low-Band Mixe r RF Input

Figure 7 details the mixer RF input configuration. The signal from the LNA passes through the external image-reject SAW filter and back into the device’s low-band mixer input terminal (MIX_IN_LOW_BAND). Minimal mixer input impedance matching is required. A high-pass shunt-L (L11) and series-C (C13) network are used for impedance matching the SAW filter output to the mixer RF input. The shunt inductor presents a short at the IF frequency. This configuration minimizes the IF leakage and prevents unwanted interfering signals at, or near, the IF frequency from degrading the mixer’s noise figure performance.

Figure 7. Low-Band Mixer RF Input Configuration

22 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Low-Band Mixer LO Input

Figure 8 details the low-band mixer LO input configuration. The input power range level for the LO buffer amplifier is flexible enough (-3 dBm to -7 dBm) to drive the mixer without entering compression. The LO signal is injected through an internal LO buffer amplifier and into the mixer. A high pass shunt-L (L14) and series-C (C17) network is used for impedance matching. The inductor also shunts to ground any un desired noise that could be injected to the mixer.

Figure 8. Low-Band Mixer LO Input Configuration

Low -Band IF Ou tput

Figure 9 details the low-band IF output configuration. The lowband mixer has a differential IF output with a 1kΩ differential

output impedance. For evaluation, a 16:1 transformer balun, with a insertion loss of 1.8 dB, is used to transform the 1kΩ differential output to a single-ended output which is then matched to 50Ω. In

the actual application, the IF output is usually connected to a narrow band channel select filter with a differential input and the transformer balun is not required.

The supply voltage (VCC) is applied to the IF pins with pull up inductors (L12, L13). A low-pass filter network is provided prior to the balun. The filter also acts as part of the impedance matching network. During optimization of the output matching network, it was found that mismatching the differential output, accomplished with C55, gives the best IIP3 performance with minimum effect on the gain and noi se figure performance. C5 5 als o hel ps to decouple the digital CMOS control line from the LO signal. The IF response is shaped by the shunt-L (L51) after the transformer balun. L51 is also used to block unwanted noise that could be reflect ed back to the mi xer . T he s eri es ca pac i t or (C51) ne ar t he LB_IF_OUT port is used as a dc block for evaluation purposes and does not have to be implemented in the end-users system.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 23

Figure 9. Low-Band IF Output Configuration

Low-B an d LO B uf fer Am pl i fie r Ou tp ut

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Figure 10 details the low-band LO buffer amplifier configuration. The low-band LO buffer amplifier can be used in either singleended or differential mode for a phase lock loop (PLL) configuration. The buffer is digitally controlled and requires a operating drive level ranging from -3 to -7 dBm. Fo r evaluation purposes, a 1:1 transformer balun, with an insertion loss of 2.7 dB, is used to convert the differential output to a single-ended output. The series capacitors at the buffer output are used for dc blocking.

The transmission line on the output of the buffer amplifier are used to convert the 100Ω differential to 50Ω differential.

The transmission lines on the output of the buffer amplifier can be modeled as microstrip lines. The values used for the calculations depend on the PCB substrate, the board stackup and the required impedance. The physical dimensions of the microstrip lines can be calculated using standard microstrip transmission line equations using the following values:

Frequency = 990 MHz ER = 4.400 (FR4), Height = 12.0000 m ils , Thickness = 1.5000

mils (Copper) Electrical Parameters: ZO = 35.350 Ohms, E_EFF = 90.000 Physical Parameters: Width = 37.777 mils , Length = 1613.305 mils

24 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Figure 10. Low-Band Buffer Amplifier Output Configuration

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 25

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Low-Band Cascaded Test Guide

This section involves measuring the cascaded performance of the Low Band LNA, Low Band MIXER and Low Band IF Amp. An external SAW filter is utilized to complete the RF receiver section.

All tests apply for an IF output terminated into a 1 kΩ differential load. To match the differential IF output to the 50 Ω test

equipmen t a transformer balun is used. All unused ports are terminated into 50 Ω.

Table 3. LB LNA, LB Mixer, SAW Filter, and LB IF Amp Parameters

PARAMETERS Min Typ Max UNIT

RF Frequency Range 869 881.5 894 MHz LO Frequency Range 979.52 992.02 1004.52 MHz IF Frequency 110.52 MHz RF Input Power -30 dB m LO Input Power -5 dBm Power Conversi on Gain 26.0 dB Power Conversi on Gain Reduction 19.0 dB Noise Figure 2.5 dB RF Input Return Loss 5.6 dB LO Input Return Loss 16.5 dB LO Buffer Output Power -10.3 dBm Power Leakage LO In to RF In -53.0 dBm Third Order Input Int er c ept Point (IIP3) -9. 7 dBm 1dB RF Input Compression Poi nt -21.0 dBm 1dB Blocking P oint -18.0 dBm

LOW-Band Cascaded: Power C onversion Gain

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The low band power conversion gain (dB) is the measured power

(dBm) at the IF frequency minus the RF source power (dBm). It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P (see Table 3). Connect the RF source to the EVM RF port, J10.

26 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

) and the desired frequency

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2) Set the LO source power (LO Pin) and the desired frequency (see Table 3). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see Table 3).

4) Connect the EVM IF output port, J11, to the spectrum analyzer.

out

5) Measure the IF output power (IF P

) at the IF fre qu ency with

the spectrum analyzer.

6) Calculate the Cascaded Gain as:

Gain = (IF P

t - RF Pin) + Transformer Loss. The

transformer loss is 1.8dB. Example: (-5dBm - (-30dBm)) + 1.8dB = 26.8 dB.

The turn on time can be adjusted by changing the values of C10, R6 and R7, as shown in Figure 21 and Figure 22. The resistors form a voltage-divider network across the supply, Vcc. The function of this network is to provide a bias condition near the ideal operating region at the base of the common emitter amplifier. By providing this bias condition, the charge time of the series capacitor, C10, can be adjusted. Changing the value of resistors should not affect gain, IIP3 or noise figure (NF) performance.

Low-Band Cascaded: Power Conversion Gain Reduction

Control state: 011010 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The Power conversion gain reduction is the delta between the

cascaded IF Pout and the strong signal IF Pout when the strong signal is enabled. Enabling the strong signal turns off the LNA. It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P

) and the desired frequency (see Table 3). Connect the RF source to the EVM RF input port, J10.

2) Set the LO source power (LO P

) and the desired frequency (see Table 3). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see Table 3).

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 27

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4) Connect the EVM IF output port, J11, to the spectrum analyzer.

out

5) Measure the output power at the IF frequency (IF P

) with the

spectrum analyzer.

6) Enable the strong signal. Measure the output power at the IF

out

frequency (SS IF P

) with the spectrum analyzer.

7) Calculate Power conversion gain reduction as:

Power Conversion Gain Reduction = (IF P

Low-Band Cascaded: Noise Figure

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 22 The cascaded Noise Figure (NF) is measured at the EVM Low

Band IF output port, J11. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transf ormer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.

Set up the nois e fi gur e met er as follows:

1) Special Function 1.4 sets the noise figure meter to measure variabl e I F and fixed LO frequenci es.

2) The IF start, stop, and step size frequencies are set to 100MHz, 120MHz, and 5MHz respectively.

out

- SS IF P

out

3) Set the smoothing to 16 or above.

4) Ensure that the Excess Noise Ratio (ENR) Table on the Noise Source head in use is entered on the NF meter.

a) On the fro nt pa nel , pre ss the EN R but to n. b) Check the ENR value by pressing the Enter button or enter

the ENR value for each frequency.

c) After enter ing the E NR for the desired frequency, press the

Frequency button on the front panel to exit.

5) To calibrate the NF Meter: a) Connect the Noise Source directly to the NF meter; press

the calibration twice

28 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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b) Next, press the Noise Figure and Gain Button. The

correcte d LED jus t ab ov e the bu tton shoul d be lit.

c) Calibration is complete. Enter the desired IF frequency to

measure.

Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator).

6) The losses are entered in the Noise Figure Meter by using special function 34.x.

a) Special Function 34.1 turns on the lo ss compensation

factor.

b) Special Function 34.2 is used to enter the loss before the

DUT.

c) Special Function 34.3 is used to enter the room

temperature in Kelvin (300°K).

d) Special Function 34.4 is used to enter the loss after the

DUT.

e) Special Function 34.0 is used to turn off the loss

compensation factor.

The noise fi gur e is me as ured as follows:

7) Connect the noise source directly to the EVM RF input port, J10.

a) A circulator between the noise source and RF input port

may help minimize any mismatches between the EVM board and t est eq ui pm e nt .

8) Connect the LO source to the EVM LO input port, J12. a) Set the LO source at the nominal power and frequency

(See Table 3).

b) Each LO frequency being tested is entered in the Noi se

figure meter by using Special function 3.1. If the source has excessive broad band noise, a filter at the LO port, J12, may be necessary to eliminate the broad band noise during testing.

9) Connect the EVM IF output port, J11, to the noise figure meter input port.

a) A bandp ass or low pass filter m ay be ne ces sary on the IF

port to eliminate the LO signal interference and get an accurate noise measurement.

10) Measure the Noise Figure.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 29

Low-Band Cascaded: RF Input Return Loss

Control state: 011000 The input return loss of the low band receiver is measured at the

EVM low band RF input port, J10. The measurement is performed using a network analyzer.

Set up the network analyzer as follows to measure the RF input return loss :

1) Set the network analyzer to measure the low band RF frequency (see Table 3).

2) Set the power range to -35 dBm th ro ugh -20 dBm, and then set the input power to -30 dBm.

3) Perform a full one-port calibration on port 1 of the ne twork analyzer.

4) Set the network analyzer to measure S11.

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5) Connect the EVM RF input, J10, to port 1 of the network analyzer.

6) Measure the RF input retu rn loss.

Low- Band Cascaded: LO Input Return Loss

Control state: 011000 The cascaded LO input return loss of the Low Band is measured

at the EVM low band LO input port, J12. The measurement is performed using a network analyzer.

1) Set the netwo rk analyzer to measure the low band LO frequency (see Table 3).

2) Set the power range to -35 dBm th ro ugh -20 dBm, and then set the input power to -30 dBm.

3) Perform a full one-port calibration on port 1 of the ne twork analyzer.

4) Set the network analyzer to measure S11.

5) Connect the EVM LO input port, J12, to port 1 of the network analyzer.

6) Measure the LO input return loss.

30 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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LOW BAND: LO Buffer Output Power

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 This section involves measuring the Low Band LO Buffer Output.

All unused ports will be terminated into 50 Ω. The LO buffer output power is measured at the EVM low band LO output port J13. A transformer balun is used to convert the differential output to a single ended output. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 3). Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency (see Table 3).

3) Connect the EVM LO buffer port, J13, to the spectrum analyzer.

4) Measure the LO buffer output power.

Low-Band: Power Leakage LO In to RF In

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO leakage at the RF port is measured at the low band RF

input port J10. Power leakage is a measure of power in dBm that couples to the RF port. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 3). Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency (see Table 3).

3) Connect the RF Port, J10, to the spectrum analyzer.

4) Measure the LO leakage power.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 31

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Low-Band Cascaded: Third Order Input Intercept Point (IIP3)

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21: The third order input intercept point is the level of the RF input

power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer.

1) Set the first RF source input power (RF P

) and frequency (F1)

(see Table 3).

2) Set the second RF source frequency to the first RF frequency plus 60kHz; F

3) Using a RF combiner, connect the RF sources to the EVM RF input port, J10.

4) Set the LO source frequency and input power (see Table 3). Connect the LO source to the EVM LO input port, J12.

5) Set the spectrum analyzer to measure at the IF frequency (F

(see Table 3).

6) Connect the EVM IF output port, J11 to the spectrum analyzer.

7) Measure the Fundamental output power at the IF frequency

Fund

8) Measure the Intermodulation products (2F2 - F1 or 2F1 - F2) at

60 kHz

9) Calculate the Intermodulation Suppression as:

Fund

Intermodulation Suppression = F

- Intermodulation

product

)

10) Calculate the Input Third -Order Intercept Point as:

Input Third-Orde r Intercept = ((Intermodulation Suppress ion/2) + (RF P

32 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

))

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Low-Band Cascaded: 1dB RF Input Compression Point

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The 1 dB input compressio n point is the RF input power at which

the gain compre sses 1 dB. Gain compression is when an increase

in P

causes no further increase in the output power (P measurement is performed using two RF sources and a spectrum analyzer.

1) Set the RF source frequency (see Table 3) and the input

power (P input port, J10.

2) Set the LO source frequency and input power (see Table 3).

Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the

IF frequency.

) to -35 dBm. Connect the RF source to the EVM RF

out

). The

4) Connect the EVM IF output port, J11, to the spectrum

analyzer.

5) Measure the output power (P

6) Calculate Gain as:

out

Gain = P

- P

7) To determine the 1 dB compression point, the RF P

increased in steps of 1 dBm unti l the gain compresses by 1 dB. Repeat step 4 and 5 until th e gain compre sses by 1dB.

RF P

-35 -10 25

-34 -9 25

-33 -8 25

-32 -7 25

-31 -6 25

-30 -5 25

-29 -4 25

-28 -3 25

-27 -2 25

-26 -1.2 24.8

-25 -0.4 24.6

out

Gain

out

) at the IF freq u ency

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 33

-24 0.4 24.4

-23 1.2 24.2

-22 2.2 24.2

-21 3.0

-20 3.0 23.0

24.0 ←1dB Compression Point

Low-Band Cascaded: 1dB Blocking Point

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The 1dB Blocking Point is a measurement of the power (dBm) of

the interfering signal, measured at the EVM IF output port J11. The measurement is performed using three sources and a spectrum analyzer.

1) Set the RF source frequency and input power (see Table 3).

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2) Set the RF Blocking source freq ue nc y to t he RF fre qu ency

minus 45 MHz at -30dBm input power.

3) Using a RF combiner, connect the RF sources to the EVM RF

port, J10.

4) Set the LO source frequency and input power (see Table 3).

Connect the LO source to the EVM LO input port, J12.

5) Set the spectrum analyzer to measure the output power at the

IF frequency.

6) Connect the EVM IF port, J11, to the spectrum analyzer.

7) To determine the 1dB Blocking Point, increase the RF

Blocking source input power until the output power at the IF freque ncy is decreased by 1dB.

8) Disconnect the Blocking source.

9) Connect the Blocking source directly to the spectrum analyzer,

and change the spectrum analyzer’s frequency to the frequency of the Blocking source.

10) Measure the power of the Blocking source.

34 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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High-Band Cascaded Receiver Section: LNA, Mixer, LO Buffer Ampli fi er

Cascaded High-Band Receiver Section:

The TRF1500 high-band receiver section, shown in Figure 11, is an integrated front-end down converter designed to operate in the 1900 MHz frequency ra nge. The high-band down converter consists of an LNA, an image-reject mixer, and LO buffer amplifier circuitry. Figure 11 details the cascaded block diagram with the image reject mixer detailed inside the dotted box.

The digital control allows the high-band receiver to operate in three different states to compensate for the environment in which the TRF1500 is operating. The high-band receiver can be operated in the normal state, where the LNA, mixer and buffer amplifier are on, the strong signal state, where the LNA is off and the mixer and buffer amplifier are on, or the transmit state, where the LNA bias current is increased to prevent compression when the transmitter is on.

The high- ba nd rec ei v er has a ty pi cal nominal gain of 26 dB , an IIP3 of -17.7 dBm and a noise figure of 4.66 dB when the receiver LO doubler is used and 4.35 dB when the high-band LO is directly driven.

LNA, Mixer, and LO Amplifier

Figure 11. Block Diagram of the High-Band Receiver Section

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 35

High-Band RF Input

Figure 12 details the high-band RF input configuration. The cascaded noise figure and input return loss performance of the high-band receiver section is determined primarily by the input matching network. The input matching network is designed for optimum noise figure performance, while maintaining good input return loss. A lo w-pass shunt-C (C20) series-L (L20) network is used for the input impedance matching. The series capacitor (C29) on the input port is used for dc blocking purposes. The enduser can optimize the input matching network for better input return loss but obtaining a be tter input match may degrade the overall c ascaded noise figure per form a nce.

Figure 12. High-Band RF Input Configuration

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High-B an d LO I n pu t

The high-band LO signal is fed through a buffer amplifier into a differential quadrature generator, which is realized using a polyphase network. The signals generated by the polyphase network are used to drive two mixers which are injected with a common RF signal. The IF signals out of these mixers will have a

180° phase shift of the image frequency as compared to the wanted RF frequency. As a result of this 180° phase shift, the IF signals at the image frequency will cancel in the quadrature combiner. The IF signal at the desired frequency will add in the quadrature combiner.

The TRF1500 offers several methods for providing high-band LO drive. The high-band LO terminal may be directly driven either single-ended or differentially. Alternately, the high-band LO terminal may be driven by using the low-band LO output and the integrat ed fr equency doubler.

36 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Figure 13 details the TRF1500 configured to utilize the low-ban d LO input and doubler as the high-band LO. The high-band LO signal is injected into the low-band LO input. The buffered signal is then routed through the doubler. The output of the doubler is routed through an external capacitor (C40) and into the singleended high-band LO input.

Figure 14 details the TRF1500 configured to utilize the high -band LO. The signal is directly injected into the high-band LO input which dir ectl y dr iv es the high-b and down converter.

Note:

L40, and change the value of C41 to 1pF and populate C24.

To use the high-band LO input, remove C40 and

Figure 13. High-Band LO Frequency Doubler Driven Configuration

Figure 14. High-Band LO Directly Driven Configuration

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 37

High-Band IF Output

Figure 15 details the high-band mixer IF output configuration. The high-band mixer has a differential IF output with a 1kΩ differen ti al output impedance. For evaluation purposes, a 16:1 transformer balun, with an insertion loss of 1.8 dB, is used to transform the 1kΩ differential output to a single-ended output which is then matched to 50Ω. In the actual application, the IF output is usually connected to a narrow band channel select filter with a differential input and the transformer balun is not required.

The supply voltage (VCC) is applied to the IF terminals with pullup inductors (L21, L22). A low-pass filter network is provided prior to the balun. The filter also acts as part of the impedance matching network. The IF response is shaped by the shunt-L (L52) after the transformer balun. L52 is also used to block unwanted noise that could be reflected back to the mixer. The series capacitor (C51) near the HB_IF_OUT port is used as a dc block for evaluation purpos es an d does not have to be implemented in the end-users system.

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Figure 15. High-Band IF Output Configuration

38 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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High-B an d LO B uf fer Am plifier Ou tpu t

Figure 16 details the high-band LO buffer amplifier configuration. The high-band LO buffer can be used in either single-ended or differential mode for a phase lock loop (PLL) configuration. The buffer is digitally controlled and requires an operating drive level ranging from -3 to -7dBm. For evaluation purposes, a 1:1 transformer balun, with an insertion loss of 2.7 dB, is used to convert the differential output to a single-ended output. The series capacitors at the buffer output are for dc blocking.

The transmission line on the output of the buffer amplifier are used to convert the 100Ω differential to 50Ω differential.

The transmission lines on the output of the buffer amplifier can be modeled as microstrip lines. The values used for the calculations depend on the PCB substrate, the board stackup and the required impedance. The physical dimensions of the microstip lines can be calculated with standard transmission line equations using the following values:

The following information are used to calculate the microstrip transmission lines:

Frequency = 2.070 GHz ER = 4.400 (FR4), Height = 12.0000 mils, Thickness = 1.5000 mils

(Copper) Electrical Parameters: ZO = 35.350, E_EFF = 90 .000 Results: Physical Parameters: Width = 37.777, Length = 771.149

Figure 16. High-Band LO Buffer Amplifier Output Configuration

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 39

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High-Band Cascaded Test Guide

This section involves measuring the cascaded performance of the High Band LNA, High Ba nd Mixer and High Band IF Amp using the Frequency Doubler. All tests apply for an IF output terminated

into a 1 kΩ differential load. A transformer balun is used to match the IF output to the 50 Ω test equipment. All unused ports are terminated into 50 Ω.

Table 4. HB LNA, HB mixer, HB IF amp

PARAMETERS Min Typ Max UNIT

RF Input Frequency Range 1930 1960 1990 MHz Direct Drive LO Frequency Range 2040.52 2070.52 2100.52 MHz Doubler Driv e LO Frequenc y Range 1020.26 1035. 26 1050.26 MHz IF Frequency 110.52 MHz RF Input Power -30 dBm LO Input Power -5 dBm Power Conversi on Gain 26.3 dB Power Conversi on Gain Reduction 43.5 dB Image Rejecti on 22.5 dB Noise Figure 4.66 dB RF Input Return Loss 14.2 dB LO Buffer Output Power -14 dB m Power Leakage LO In to RF In -50 dBm Third Order Input Intercept Point(IIP3) -17.7 dBm 1dB RF Input Compression Poi nt -23.7 dBm 2X2 Spur Performance 69 dBc 3X3 Spur Performance 81 dBc

High-Ban d C asc a de d: Pow er Con ver sion Gain

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The high band power conversion gain (dB) is the measured power

(dBm) at the IF frequency minus the RF source power (dBm). It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P

(see Table 4). Connect the RF source to the EVM RF port, J20.

40 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

) and the desired frequency

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2) Set the LO source power (LO Pin) and the desired frequency

(see Table 4). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see

Table 4).

4) Connect the EVM IF output port, J21, to the spectrum

analyzer.

out

5) Measure the IF output power (IF P

) at the IF fre qu ency with

the spectrum analyzer.

6) Calculate the Cascaded Gain as:

Gain = (IF P

out

- RF Pin) + Transformer Loss. The

transformer loss is 1.8dB.

High-B an d Casc a de d: Pow er Con ver sion Gain Re du cti on

Control state: 111011 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The Power conversion gain reduction is the delta between the

cascaded IF Pout and the strong signal IF Pout when the strong signal is enabled. Enabling the strong signal turns off the LNA. It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P

(see Table 4). Connect the RF source to the EVM RF input port, J20.

2) Set the LO source power (LO P

(see Table 4). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see

Table 4).

) and the desired frequency

4) Connect the EVM IF output port, J21, to the spectrum

analyzer.

out

5) Measure the output power at the IF frequency (IF P

) with the

spectrum analyzer.

6) Enable the strong signal. Measure the output power at the IF

out

frequency (SS IF P

) with the spectrum analyzer.

7) Calculate Power conversion gain reduction as:

out

Power Conversion Gain Reduction = (IF P

- SS IF P

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 41

out

High-Band Cascaded: Image Rejection

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 Image Rejection is a signal that appears at twice the IF distance

from the desired RF signal, located on the opposite side of the LO frequency from the desired RF signal. The measurement is performed using two RF sources and a spectrum analyzer.

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1) Set the RF source power (RF P

frequency (F

) (see Table 4). Connect the RF source to the

) and the desi r ed RF

EVM RF input port, J20.

2) Set the LO source power (LO P

frequency (F

)(see Table 4). Connect the LO source to the

) and the desi r ed LO

EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency

)(see Table 4).

4) Connect the EVM IF output port, J21, to the spectrum

analyzer.

out

5) Measure the output power at the IF frequency (IF P

) with the

spectrum analyzer.

6) Set the RF Frequency to F

7) Measure the output power at the IF frequency (IF P

+ 2 F

IF.

out

) with the

spectrum analyzer

8) Calculate the Image Rejection as

Image Rejection = ∆ between the IF output power at ( F and the IF output power at F

+ 2 F

)

42 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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High-Band Cascaded: Noise Figure

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 22 The cascaded Noise Figure (NF) is measured at the EVM Low

Band IF output port, J21. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transf ormer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.

Set up the nois e fi gur e met er as follows:

1) Special Function 1.4 sets the noise figure meter to measure

variabl e I F and fixed LO frequenci es.

2) The IF start, stop, and step size frequencies are set to

100MHz, 120MHz, and 5MHz respectively.

3) Set the smoothing to 16 or above.

4) Ensure that the Excess Noise Ratio (ENR) Table on the Noise

Source head in use is entered on the NF meter. a) On the fro nt pa nel , pre ss the EN R but to n. b) Check the ENR value by pressing the Enter button or enter

the ENR value for each frequency.

c) After enter ing the E NR for the desired frequency, press the

Frequency button on the front panel to exit.

5) To calibrate the NF Meter:

a) Connect the Noise Source directly to the NF meter; press

the calibration button twice.

b) Next, press the Noise Figure and Gain Button. The

correcte d LED jus t ab ov e the bu tton shoul d be lit.

c) Calibration is complete. Enter the desired IF frequency to

measure.

Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator).

6) The losses are entered in the Noise Figure Meter by using

special function 34.x.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 43

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a) Special Function 34.1 turns on the lo ss compensation

factor.

b) Special Function 34.2 is used to enter the loss before the

DUT.

c) Special Function 34.3 is used to enter the room

temperature in Kelvin (300°K).

d) Special Function 34.4 is used to enter the loss after the

DUT.

e) Special Function 34.0 is used to turn off the loss

compensation factor.

The noise fi gur e is me as ured as follows:

7) Connect the noise source directly to the EVM RF input port,

J20. a) A circulator between the noise source and RF input port

may help minimize any mismatches between the EVM board and t est eq ui pm e nt .

8) Connect the LO source to the EVM LO input port, J12.

a) Set the LO source at the nominal power and frequency

(See Table 4).

b) Each LO frequency being tested is entered in the Noi se

figure meter by using Special function 3.1. If the source has excessive broad band noise, a filter at the LO port, J12, may be necessary to eliminate the broad band noise during testing.

9) Connect the EVM IF output port, J21, to the noise figure meter

input port. a) A bandp ass or low pass filter m ay be ne ces sary on the IF

port to eliminate the LO signal interference and get an accurate noise measurement.

10) Measure the Noise Figure.

High-Band Cascaded: RF Input Return Loss

Control state: 111001 The cascaded input return loss of the high band is measured at

the high band RF input port, J20. The measurement is performed using a network analyzer.

Set up the network analyzer as follows to measure the RF input return loss :

44 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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1) Set the network analyzer to measure the low band RF

frequency (see Table 4).

2) Set the power range to -35 dBm th ro ugh -20 dBm, and then

set the input power to -30 dBm.

3) Perform a full one-port calibration on port 1 of the ne twork

analyzer.

4) Set the network analyzer to measure S11.

5) Connect the EVM RF input, J20, to port 1 of the network

analyzer.

6) Measure the RF input retu rn loss.

High-Band: LO Buffer Output Power

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 This section involves measuring the Low Band LO Buffer Output.

All unused ports will be terminated into 50 Ω. The LO buffer output power is measured at the EVM low band LO output port J23. A transformer balun is used to convert the differential output to a single ended output. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 4).

Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency

(see Table 4).

3) Connect the EVM LO buffer port, J23, to the spectrum

analyzer.

4) Measure the LO buffer output power.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 45

High-Band Cascaded: Power Leakage LO In to RF In

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO leakage at the RF port is measured at the low band RF

input port J20. Power leakage is a measure of power in dBm that couples to the RF port. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 4).

Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency

(see Table 4).

3) Connect the RF Port, J20, to the spectrum analyzer.

4) Measure the LO leakage power.

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High-Band Cascaded: Third Order Input Intercept Point (IIP3)

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The third order input intercept point is the level of the RF input

power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer.

1) Set the first RF source input power (RF P

(see Table 4).

2) Set the second RF source frequency to the first RF frequency

plus 120kHz; F

3) Using a RF combiner, connect the RF sources to the EVM RF

input port, J20.

4) Set the LO source frequency and input power (see Table 4).

Connect the LO source to the EVM LO input port, J12.

) and frequency (F1)

5) Set the spectrum analyzer to measure at the IF frequency (F

(see Table 4).

46 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

)

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6) Connect the EVM IF output port, J21 to the spectrum analyzer.

7) Measure the Fundamental output power at the IF frequency

Fund

8) Measure the Intermodulation products (2F

120 kHz

- F1 or 2F1 - F2) at

9) Calculate the Intermodulation Suppression as:

Fund

Intermodulation Suppression = F

- Intermodulation

product

10) Calculate the Input Third -Order Intercept Point as:

Input Third-Orde r Intercept = ((Intermodulation Suppress ion/2) + (RF P

))

High-Band Cascaded: 1dB Input Compress ion Point

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The 1 dB input compressio n point is the RF input power at which

the gain compre sses 1 dB. Gain compression is when an increase

in P

causes no further increase in the output power (P measurement is performed using two RF sources and a spectrum analyzer.

out

). The

1) Set the RF source frequency (see Table 4) and the input

power (P

) to -35 dBm. Connect the RF source to the EVM RF

input port, J20.

2) Set the LO source frequency and input power (see Table 4).

Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the

IF frequency.

4) Connect the EVM IF output port, J21, to the spectrum

analyzer.

out

5) Measure the output power (P

) at the IF freq u ency

6) Calculate Gain as:

out

Gain = P

7) To determine the 1 dB compression point, the RF P

- P

is increased in steps of 1 dBm unti l the gain compresses by 1 dB. Repeat step 4 and 5 until th e gain compre sses by 1dB.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 47

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RF P

out

Gain

-35 -10 25

-34 -9 25

-33 -8 25

-32 -7 25

-31 -6 25

-30 -5 25

-29 -4 25

-28 -3 25

-27 -2 25

-26 -1.2 24.8

-25 -0.4 24.6

-24 0.4 24.4

-23 1.2 24.2

-22 2.2 24.2

-21 3.0

24.0 ←1dB Compression Point

-20 3.0 23.0

High-Band Cascaded: 2X2 Spur Performance

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 2X2 Spur Performance is measured at IF output port J21. The

measurement is performed using two sources and a spectrum analyzer.

1) Set the RF source frequency (F

RF)

and input power (see Table

4). Connect the RF source to the EVM RF input port, J20.

2) Set the LO source frequency and input power (see Table 4). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the IF frequency; F

4) Connect the EVM IF output port, J21, to the spectrum analyzer.

out

5) Measure the output power (1 P

6) Set the RF source Frequency to (F

) at the IF freq uen cy .

+ ½ FIF) and Pin to -

50dBm.

out

7) Measure the output power (2 P

) at the IF freq uen cy .

48 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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8) Calculate 2 X 2 spur performance as 2 X 2 spur performance = 1 P

out

- 2 P

out.

High Band: 3X3 Spur Performance

Control state: 111001 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 3X3 Spur Performance is measured at IF output port J21. The

measurement is performed using two sources and a spectrum analyzer.

1) Set the RF source frequency (F

RF)

and input power (see Table

4). Connect the RF source to the EVM RF input port, J20.

2) Set the LO source frequency and input power (see Table 4). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the IF frequency; F

4) Connect the EVM IF output port, J21, to the spectrum analyzer.

out

5) Measure the output power (1 P

6) Set the RF source Frequency to (F

) at the IF freq uen cy .

+ 2/3 FIF) and the source

power to -50dBm.

out

7) Measure the output power (2 P

) at the IF freq uen cy .

8) Calculate 3 x 3 spur per for m ance as:

3 x 3 spur performance = 1 P

out

- 2 P

out.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 49

Low-Band and High-Ba nd Transmit

Low- and High-Band Transmit Mixer

Figure 17 details the block diagram of the transmit mixer. The TRF1500 provides a transmit mixer for down converting the system transmit signal (low-band or high-band) to a common IF for loop-back testing. The LO input for this mixer can be selected from either the low-band LO input or the high-band LO input by means of the digital control. The RF input of the transmit mixer

provides a broad-band 200Ω differential input impedance over a band of 800 MHz to 2GHz and thus requires minimal external matching.

The mixer is a double-balanced G ilbert cell design with open collector outputs. The Gilbert cell structure was implemented for its robust isolation and harmonic suppression characteristics.

Figure 17. Transmit Mixer Block Diagram

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Low-Band and High-Band Transmit Mixer RF Input

Figure 18 details the transmit mixer RF input configuration. The transmit mixer can be either driven single-ended or differentially. For evaluation purposes, a 4:1 transformer balun is used on the EVM to drive the transmit mixer single-ended. The input requires very little external matching. A shunt capacitor (C35) near the input port (J30) and a shunt capacitor (C36) near the transformer balun (T30) are the only input impedance matching components required.

50 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Figure 18. Low- and High-Band Transmit Mixer RF Input Configuration

Low- and High-Band Transmit Mixer IF Output

Figure 19 details the transmit mixer IF output configuration. The transmit mixer has a differential IF output with a 1kΩ differen ti al impedance. For evaluation purposes, a 16:1 transformer balun, with an insertion loss of 1.8 dB, is used to transform the 1k differential output to a single-ended output which is then matched to 50Ω.

Ω

The supply voltage (VCC) is applied to the IF pins with pull up inductors (L30, L31). A low-pass filter network is provided prior to the balun. This filter also acts as part of the impedance matching network. The IF response is shaped by the shunt inductor (L50) after the transformer balun. L50 is also used to block unwanted noise that could be reflected back to the mixer. The series capacitor (C50), near the TX_IF_OUT port, is used as a dc block for evaluation purposes and does not have to be implemented in the end-users system.

Figure 19. Low- and High-Band Transmit Mixer IF Output Configuration

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 51

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Low-Band Transmit M ixer Test Guide

This section involves measuring the Transmit Mixer perf ormance. All tests apply for an IF output terminated into a 1 kΩ differential load. To match the IF output to the 50 Ω test equipment a transformer balun is used. All unused ports are terminated into 50

Ω

Table 5. Low-Band Transmit Performance Parameters

PARAMETERS Min Typ Max UNIT

Tx Mixer Input Frequenc y Range 824 836. 5 849 MHz LO Input Frequency Range 941 953. 5 966 MHz Tx Mixer IF Frequency 117 MHz RF Input Power -30 dBm LO Input Power -5 dBm Power Conversi on Gain 19 dB Noise Figure 7.8 dB Input Return Loss 9.8 dB Power Leakage LO In to Tx In -49 dB Power Leakage Tx I n to LO In -70.6 dB 1dB Input Compression Point -20 dBm Second Order Input intercept Point (IIP2) 29.5 dBm Third Order Input Intercept Point(IIP3) -11.5 dBm

Low-Band Transmit Mixer: Power Conversion Gain

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The low band transmit mixer power conversion gain (dB) is the

measured power (dBm) at the IF frequency minus the RF source power (dBm). It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P (see Table 5). Connect the RF source to the EVM RF port, J30.

2) Set the LO source power (LO P (see Table 5). Connect the LO source to the EVM LO input port, J12.

52 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

) and the desired frequency

SWRA004A

3) Set the spectrum analyzer to measure at the IF frequency (see Table 5).

4) Connect the EVM IF output port, J31, to the spectrum analyzer.

5) Measure the IF output power (IF P the spectrum analyzer.

6) Calculate the Cascaded Gain as:

out

Gain = (IF P

- RF Pin) + Transformer Loss. The

transformer loss is 1.8dB.

Low-Band Transmit Mixer: Noise Figure

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 22 The cascaded Noise Figure (NF) is measured at the EVM Low

Band IF output port, J31. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transf ormer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.

out

) at the IF fre qu ency with

Set up the nois e fi gur e met er as follows:

1) Special Function 1.4 sets the noise figure meter to measure variabl e I F and fixed LO frequenci es.

2) The IF start, stop, and step size frequencies are set to 114MHz, 120MHz, and 3MHz respectively.

3) Set the smoothing to 16 or above.

4) Ensure that the Excess Noise Ratio (ENR) Table on the Noise Source head in use is entered on the NF meter.

a) On the fro nt pa nel , pre ss the EN R but to n. b) Check the ENR value by pressing the Enter button or enter

the ENR value for each frequency.

c) After enter ing the E NR for the desired frequency, press the

Frequency button on the front panel to exit.

5) To calibrate the NF Meter: a) Connect the Noise Source directly to the NF meter; press

the calibration button twice.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 53

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b) Next, press the Noise Figure and Gain Button. The

correcte d LED jus t ab ov e the bu tton shoul d be lit.

c) Calibration is complete. Enter the desired IF frequency to

measure.

Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator).

6) The losses are entered in the Noise Figure Meter by using special function 34.x.

a) Special Function 34.1 turns on the lo ss compensation

factor.

b) Special Function 34.2 is used to enter the loss before the

DUT.

c) Special Function 34.3 is used to enter the room

temperature in Kelvin (300°K).

d) Special Function 34.4 is used to enter the loss after the

DUT.

e) Special Function 34.0 is used to turn off the loss

compensation factor.

The noise fi gur e is me as ured as follows:

7) Connect the noise source directly to the EVM RF input port, J30.

8) Connect the LO source to the EVM LO input port, J12. a) Set the LO source at the nominal power and frequency

(See Table 5).

b) Each LO frequency being tested is entered in the Noi se

figure meter by using Special function 3.1.

9) Connect the EVM IF output port, J31, to the noise figure meter input port.

10) Measure the Noise Figure.

Low-Band Transmit Mixer: Input Return Loss

Control state: 010100 The cascaded input return loss of the low band transmit mixer is

measured at the EVM low band RF input port, J30. The measurement is performed using a network analyzer.

Set up the network analyzer as follows to measure the RF input return loss :

54 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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1) Set the network analyzer to measure the low band RF frequency (see Table 5).

2) Set the power range to -35 dBm th ro ugh -20 dBm, and then set the input power to -30 dBm.

3) Perform a full one-port calibration on port 1 of the ne twork analyzer.

4) Set the network analyzer to measure S11.

5) Connect the EVM RF input, J30, to port 1 of the network analyzer.

6) Measure the RF input retu rn loss.

Low-Band Transmit Mixer: Power Leakage LO In to TX In

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO In leakage at the TX In port is measured at the low band

TX input port J30. Power leakage is a measure of power (in dBm) that couples to the TX port. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 5). Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency (see Table 5).

3) Connect the TX In Port, J30, to the spectrum analyzer.

4) Measure the LO leakage power.

Low-Band Transmit Mixer: Power Leakage TX In to LO In

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUP Test setup Figure 24 The Power leakage from TX IN to LO IN is measured at the LO in

port, J12. A leakage is a measure of power (in dBm) that couples to the LO IN port. The measurement is performed using a RF source and a spectrum analyzer.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 55

1) Set the TX source frequency and input power (see Table 5). Connect the TX source to the EVM TX input port, J30.

2) Set the spectrum analyzer to measure at the T X frequency (see Table 5).

3) Connect the LO In Port, J12, to the spectrum analyzer.

4) Measure the TX leakage power.

Low-Ban d Tran sm it Mixer : 1dB Inp ut Compressi on Point

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The 1 dB input compression point is the TX RF input power at

which the gain compresses 1 dB. Gain compressio n is when an

increase in P

out

). The measurement is performed using two RF sources and a

(P spectrum analyzer.

causes no further increase in the output power

SWRA004A

1) Set the TX RF source frequency (see Table 5) and the input power (P

) to -35 dBm. Connect the RF source to the EVM RF

input port, J30.

2) Set the LO source frequency and input power (see Table 5). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the IF frequency.

4) Connect The EVM TX IF output port, J31, to the spectrum analyzer.

5) Measure the output power (P

6) To determine the 1 dB compression point, the TX RF P increased in steps of 1 dBm unti l the gain compresses by 1 dB. Repeat step 4 and 5 until th e gain compre sses by 1dB.

7) Calculate Gain as:

out

Gain = P

RF P

-35 -16 19

-34 -15 19

-33 -14 19

-32 -13 19

out

- P

Gain

out

) at the IF freq u ency

56 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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-31 -12 19

-30 -11.2 18. 8

-29 -10.2 18. 8

-28 -9.2 18.8

-27 -8.4. 18.6

-26 -7.6 18.4

-25 -7.8 18.2

-24 -6.0

-23 -5.5 17.5

18.0←1dB Compression Point

Low-Band Tra n smit Mixer: Second Order Input Intercept Point (IIP2)

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 Input intercept point is the level of input RF power at which the

output power levels of the undesired intermodulation products and IF products are equal. The second order intercept point is measured at the IF output port, J31.

1) Set the RF source input power (RF P

) and frequency (see

Table 5).

2) Set the LO source input power and frequency (see Table 5). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see Table 5).

4) Connect the EVM IF output port, J31 to the spectrum analyzer.

5) Measure the IF output power (IF 1P

out

) at the IF frequency.

6) Increase the RF freq ue nc y by half the IF frequency.

in +

out

) at the IF Frequency.

[IF 1P

out

- IF 2P

out

]

7) Measure the IF output power (IF 2P

8) Calculate IIP2 as: IIP2 = RF P

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 57

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Low-Band Transmit Mixer: Third Order Inpu t Intercept Point (IIP3)

Control state: 010100 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The third order input intercept point is the level of the RF input

power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer.

1) Set the first RF source input power (RF P

) and frequency

(F1) (see Table 5).

2) Set the second RF source frequency to the first RF frequency plus 60kHz; F

3) Using a RF combiner, connect the RF sources to the EVM RF input port, J30.

4) Set the LO source frequency and input power (see Table 5). Connect the LO source to the EVM LO input port, J12.

5) Set the spectrum analyzer to measure at the IF frequency (F

(see Table 5).

6) Connect the EVM IF output port, J31 to the spectrum analyzer.

7) Measure the Fundamental output power at the IF frequency

Fund

8) Measure the Intermodulation products (2F

60 kHz

- F1 or 2F1 - F2) at

9) Calculate the Intermodulation Suppression as:

Fund

Intermodulation Suppression = F

- Intermodulation

product

)

10) Calculate the Input Third -Order Intercept Point as:

Input Third-Orde r Intercept = ((Intermodulation Suppress ion/2) + (RF P

58 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

))

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High-Band Transmit Mixer Test Guide

This section involves measuring the High Band Transmit Mixer performance. All tests apply for an IF output terminated into a 1

kΩ differential load. To match the IF output to the 50 Ω test equipmen t a transformer balun is used. All unused ports are

terminated into 50 Ω. Testing the performance of the high transmit mixer can be performed two ways. One being the LO Doubler driven, no EVM modification needed. Two LO is directly driven, before measuring the high band transmit mixer performance the EVM board must be modified as follows: Remove L40 and C41, add C24. This enables the high band transmit to be directly driven by an LO source.

Table 6. High-Band Transmit Mixer Performance Parameters

PARAMETERS Min Typ Max U NIT

Tx Mixer Input Frequenc y 1850 1880 1910 MHz LO Frequency Directly Driven 1733 1763 1793 MHz LO Frequency Doubler Driven 983.5 998.5 1013.5 MHz Tx Mixer Output Frequency 117 MHz LO Input Power -5.0 dBm RF Input Power -30 dBm Power Conversi on Gain 9.9 dB Noise Figure 12.7 dB RF Input Return Loss 16.6 dB Power Leakage Tx I n to LO In -55.5 dB Power Leakage LO In to Tx In -69.5 dB 1dB Input Compression Point -15.7 dBm Second Order Input Intercept point (IIP2) 27 dBm Third Order Input Intercept Point(IIP3) -6.7 dBm

To test the High Band Transmit Mixer parameters use the procedure for the Low Band Transmit Mixer, with the following exception: Control state mode 110100 and when testing the Third order intercept point the RF signal separation is 120kHz.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 59

Low-Band LNA Stand-Alone Test Guide

This section involves measuring the Low Band LNA by itself. All unused ports are terminated into 50Ω. Before measuring the low band LNA by itself the EVM board must be modified as follows: Remove C12 and place C53. The EVM board is now modified to use J15 as the output port of the LNA.

Table 7. Low-Band LNA Parameters

Parameters Min Typ Max Units

RF Frequency Range 869 881.5 894 MHz RF Input Power -30 dBm Gain 15.5 dB RF Input Return Loss -6.5 dB RF Output return loss -14 dB Isolation -17.2 dB Noise Figure 1.8 dB Third Order Input Intercept Point(IIP3) -3 dBm 1dB Input compression P oint -13.5 dBm

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Low-Band LNA: Gain

Control state: 011000 The LNA gain is measured from the input port J10 through the

output port J15. The measurement is performed using a network analyzer.

1) Set up the network analyzer to measure the low band RF frequency range (see Table 7).

2) Set the power range to -35 dBm to -20 dBm, a) Set the input power to -30 dBm.

3) Perform a full two-port calibration.

4) Connect the low band LNA input port J10 and output port J15 to the S11 and S22 port of the network analyzer respectively.

5) Set the network analyzer to measure S21.

6) Measure the gain

Low-Band LNA: Input Return Loss

Control state: 011000

60 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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The LNA input return loss is measured at the input Port J10. Using the calibration performed above, set the network analyzer to measure S11.

Low-B an d LN A: Output Return Loss

Control state: 011000 The LNA output return loss is measured at the output port J15.

Using the calibration performed above, set the network analyzer to measure S22.

Low-B an d LNA: Isola tion

Control state: 011000 The isolation of the Low Band LNA is a measur e of the attenuation

between the outp ut o f the LN A an d the input o f the LN A. . Use the calibration performed above; set the network analyzer to measure S12.

Low-Band LNA: 1dB Input Compression Point

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 27 The 1 dB input compressio n point is the RF input power at which

the gain compresses 1 dB and when an increase in P further increase in the output power (P performed using two RF sources and a spectrum analyzer.

1) Set the RF source frequency (see Table 7) and the input

power (P

) to -35 dBm. Connect the RF source to the EVM RF

input port, J10.

2) Set the spectrum analyzer to measure the output power at the desired LNA frequency.

3) Connect The EVM LNA output port, J15, to the spectrum analyzer.

4) Measure the output power (P

5) Calculate Gain as:

out

) at the LNA fr eq uen c y

caus es no

). The measurement is

out

Gain = P

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 61

- P

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6) To determine the 1 dB compression point, the RF P increased in steps of 1 dBm unti l the gain compresses by 1 dB. Repeat step 4 and 5 until th e gain compre sses by 1dB.

RF P

-35 -20 15

-34 -19 15

-33 -18 15

-32 -17 15

-31 -16 15

-30 -15 15

-29 -14 15

-28 -13 15

-27 -12 15

-26 -11 14.8

-25 -10.4 14.6

-24 -9.4 14.6

-23 -8.8 14.2

-22 -7.8 14.2

-21 -7.0

-20 -7.0 13.0

out

Gain

14.0 ←1dB Compression Point

Low-Band LNA: Noise Figure

Control state: 011000

SEE APPENDIX A: TEST BENCH SETUPS

Test setup Figure 25 The LNA Noise Figure (NF) is measured at the LNA output port

J15. The measurement is performed using an HP8970B Noise Figure Meter.

1) Set up the Noise figure meter as follows:

2) Set start; stop frequency (see Table 7) and the step size to

12.5 MHz.

3) Set the smoothing to 16 or above.

4) Insure that the Excess Noise Ratio (ENR) Table on the Noise Source head in use is entered on the NF meter.

a) On the front panel press ENR button. b) Check the ENR value by pressing the Enter button or enter

the ENR value for each frequency.

62 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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c) After enter ing the E NR for the desired frequency, press the

Frequency button on the front panel to exit.

5) To calibrate the NF Meter:

a) Connect the Noise Source directly to the NF meter; press

the calibration button twice.

b) Next, press the Noise Figure and Gain Button. The

correcte d LED jus t ab ov e the bu tton shoul d be lit.

c) Calibration is complete.

Next the external equipment loss is considered (RF cable, Transmission line).

6) The Losses are entered in the Noise Figure Meter by using special function 34.x.

a) Special Function 34.1 turns on the Loss compensation

factor.

b) Special Function 34.2 is used to enter the loss before the

DUT.

c) Special Function 34.3 is used to enter the room

temperature in Kelvin (300°K).

d) Finally Special Function 34.4 is used to enter the loss after

the DUT.

e) Special Function 34.0 is used to turn off the loss

compensation factor.

The noise fi gur e is me as ured as follows:

7) Connecting the noise source directly to the Low Band LNA input port, J10.

8) Connect the EVM LNA output port, J15, to the noise figure meter input port.

9) Measure the nois e fi gure for each frequency.

Low-Band LNA: Th ird Order Input Inte rcept Point (IIP3)

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 26

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 63

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The third order input intercept point is the level of the RF input power at which the output power levels of the undesired intermodulation products and the desired products are equal. The measurement is performed using two RF sources and a spectrum analyzer.

1) Set the first RF source input power (RF P

) and frequency

(F1) (see Table 7).

2) Set the second RF source frequency to the first RF frequency plus 60kHz; F

3) Using a RF combiner, connect the RF sources to the EVM RF input port, J10.

4) Set the spectrum analyzer to measure at the RF frequency

(see Table 7).

(F1

)

5) Connect the EVM IF output port, J11 to the spectrum analyzer.

6) Measure the Fundamental output power at the RF frequency

Fund

7) Measure the Intermodulation products (2F

60 kHz

- F1 or 2F1 - F2) at

8) Calculate the Intermodulation Suppression as:

Fund

Intermodulation Suppression = F

- Intermodulation

product

9) Calculate the Inpu t Third -Order Intercept Point as:

Input Third-Orde r Intercept = ((Intermodulation Suppress ion/2) + (RF P

64 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

))

SWRA004A

Low-Band Recei v er Mixer Sta nd- Alone Test Guide

This section involves measuring the Low Band Receiver Mixer. All unused ports will be terminated into 50 Ω. Before measuring the low band Mixer separately, the EVM board must be modified as follows: Remove C12 and place C54. The EVM board is now modified to use J15 as the input port of the Receiver Mixer.

Table 8. Low-Band Receiver Mixer Parameters

PARAMETERS Min Typ Max UNIT

Rx Mixer Input Frequency 869 881.5 894 MHz LO frequency 979.52 992.02 1004.52 MHz Rx Mixer Output Frequency 110.52 MHz RF Input Power -30 dBm LO Input Power -5 dBm Power Conversi on Gain 12 dB RF Input Return Loss 9 dB Power Leakage LO In at RF In -50 dB Noise Figure 7.5 dB 1dB Input Compression Point -6 dBm Third Order Input Intercept Point(IIP3) 3.5 dBm

Low-Band Receiver Mixer: Power Conversion Gain

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The receiver mixer conversion gain (dB) is the measured power

(dBm) at the IF frequency minus the RF source power (dBm). It is measured using a RF source and a spectrum analyzer.

1) Set the RF source power (RF P (see Table 8). Connect the RF source to the EVM RF port, J15.

2) Set the LO source power (LO P (see Table 8). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure at the IF frequency (see Table 8).

4) Connect the EVM IF output port, J11, to the spectrum analyzer.

) and the desired frequency

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 65

SWRA004A

5) Measure the IF output power (IF P the spectrum analyzer.

6) Calculate the Cascaded Gain as:

out

Gain = (IF P

- RF Pin) + Transformer Loss. The

transformer loss is 1.8dB.

Low-Band Receiver Mixer: Input Return Loss

Control state: 011000 The input return loss of the low band receiver mixer is measured

at the low band RF input port J15. The measurement is performed using a network analyzer. The network analyzer is set up to measure the low band receiver frequency range (see Table

8). The network analyzer power range is set to 35 dBm to -20

dBm; the input power is set to -30 dBm. Perform a full one-port or two-port calibration. Set the network analyzer to measure S11. To measure the receiver mixer input return loss, connect the RF input port J15 to S11 port of the network analyzer.

The input return loss of the low band mixer is measured at the low band mixer input port, J15. The measurement is performed using a network analyzer.

out

) at the IF fre qu ency with

Set up the network analyzer as follows to measure the RF input return loss :

1) Set the network analyzer to measure the low band RF frequency (see Table 8).

2) Set the power range to -35 dBm th ro ugh -20 dBm, and then set the input power to -30 dBm.

3) Perform a full one-port calibration on port 1 of the ne twork analyzer.

4) Set the network analyzer to measure S11.

5) Connect the EVM RF input, J15, to port 1 of the network analyzer.

6) Measure the RF input retu rn loss.

66 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

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Low-Band Receiver Mixer: Power Leakage LO In to RF In

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 23 The LO leakage at the RF port is measured at the low band mixer

RF input port, J15. Powe r leakage is a measure of power in dBm that couples to the RF port. The measurement is performed using a RF source and a spectrum analyzer.

1) Set the LO source frequency and input power (see Table 8). Connect the LO source to the EVM LO input port, J12.

2) Set the spectrum analyzer to measure at the LO frequency (see Table 8).

3) Connect the RF Port, J15, to the spectrum analyzer.

4) Measure the LO leakage power.

Low-Band Receiver Mixer: Noise Figure

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 22: The low band mixer Noise Figure (NF) is measured at the EVM

Low Band IF output port, J11. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transformer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.

Set up the nois e fi gur e met er as follows:

1) Special Function 1.4 sets the noise figure meter to measure variabl e I F and fixed LO frequenci es.

2) The IF start, stop, and step size frequencies are set to 100MHz, 120MHz, and 5MHz respectively.

3) Set the smoothing to 16 or above.

4) Ensure that the Excess Noise Ratio (ENR) Table on the Noise Source head in use is entered on the NF meter.

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 67

SWRA004A

a) On the fro nt pa nel , pre ss the EN R but to n. b) Check the ENR value by pressing the Enter button or enter

the ENR value for each frequency.

c) After enter ing the E NR for the desired frequency, press the

Frequency button on the front panel to exit.

5) To calibrate the NF Meter: a) Connect the Noise Source directly to the NF meter; press

the calibration button twice.

b) Next, press the Noise Figure and Gain Button. The

correcte d LED jus t ab ov e the bu tton shoul d be lit.

c) Calibration is complete. Enter the desired IF frequency to

measure.

Next, the external equipment Loss is considered (RF cable, Transmission line, filter and circulator).

6) The losses are entered in the Noise Figure Meter by using special function 34.x.

a) Special Function 34.1 turns on the lo ss compensation

factor.

b) Special Function 34.2 is used to enter the loss before the

DUT.

c) Special Function 34.3 is used to enter the room

temperature in Kelvin (300°K).

d) Special Function 34.4 is used to enter the loss after the

DUT.

e) Special Function 34.0 is used to turn off the loss

compensation factor.

The noise fi gur e is me as ured as follows:

7) Connect the noise source directly to the EVM RF input port, J15.

a) A circulator between the noise source and RF input port

may help minimize any mismatches between the EVM board and t est eq ui pm e nt .

8) Connect the LO source to the EVM LO input port, J12. a) Set the LO source at the nominal power and frequency

(See Table 8).

b) Each LO frequency being tested is entered in the Noi se

figure meter by using Special function 3.1. If the source has excessive broad band noise, a filter at the LO port,

68 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

SWRA004A

J12, may be necessary to eliminate the broad band noise during testing.

9) Connect the EVM IF output port, J11, to the noise figure meter input port.

a) A bandp ass or low pass filter m ay be ne ces sary on the IF

port to eliminate the LO signal interference and get an accurate noise measurement.

10) Measure the Noise Figure.

Low-Band Receiver Mixer: 1dB RF Input Compression Point

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 20 The 1 dB input compression point is the TX RF input power at

which the gain compresses 1 dB. Gain compressio n is when an

increase in P

out

). The measurement is performed using two RF sources and a

(P spectrum analyzer.

causes no further increase in the output power

1) Set the Mixer RF source frequency (see Table 8) and the input power (P

) to -35 dBm. Connect the RF source to the EVM RF

input port, J15.

2) Set the LO source frequency and input power (see Table 8). Connect the LO source to the EVM LO input port, J12.

3) Set the spectrum analyzer to measure the output power at the IF frequency.

4) Connect The EVM Mixer IF output port, J11, to the spectrum analyzer.

5) Measure the output power (P

6) Calculate Gain as:

out

Gain = P

- P

7) To determine the 1 dB compression point, the mixer RF P increased in steps of 1 dBm unti l the gain compresses by 1 dB. Repeat step 4 and 5 until th e gain compre sses by 1dB.

RF P

-25 -15 10

-24 -14 10

out

Gain

out

) at the IF freq u ency

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 69

SWRA004A

-23 -13 10

-22 -12. 2 9. 8

-21 -11. 4 9. 6

-20 -10. 4 9. 6

-19 -9.6 9.4

-18 -8.7 9.3

-17 -7.8 9.2

-16 -6.8 9.2

-15 -6.0

-14 -5.5 8.5

9.0 ←1dB Compression Point

Low-Band Receiver Mixer: Third Order Input Intercept Point (IIP3)

Control state: 011000 SEE APPENDIX A: TEST BENCH SETUPS Test setup Figure 21 The third order input intercept point is the level of the RF input

power at which the output power levels of the undesired intermodulation products and the desired IF products are equal. The measurement is performed using three RF sources and a spectrum analyzer.

1) Set the first RF source input power (RF P

) and frequency

(F1) (see Table 8).

2) Set the second RF source frequency to the first RF frequency plus 60kHz; F

3) Using a RF combiner, connect the RF sources to the EVM RF input port, J15.

4) Set the LO source frequency and input power (see Table 8). Connect the LO source to the EVM LO input port, J12.

5) Set the spectrum analyzer to measure at the IF frequency (F

(see Table 8).

6) Connect the EVM IF output port, J11 to the spectrum analyzer.

7) Measure the Fundamental output power at the IF frequency

Fund

)

8) Measure the Intermodulation products (2F

60 kHz

- F1 or 2F1 - F2) at

9) Calculate the Intermodulation Suppression as:

70 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

SWRA004A

Intermodulation Suppression = F

Fund

- Intermodulation

product

10) Calculate the Input Third -Order Intercept Point as:

Input Third-Orde r Intercept = ((Intermodulation Suppress ion/2) + (RF P

))

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 71

SWRA004A

Appendix A: Te s t Bench Conf iguration

Figure 20. Test Bench Setup: Power Conversion Gain, Power Conversion Gain

Reduction, 1dB RF Input Compression Point, Second Order Input

Intercept Point (IIP2), 2x2 Spur Performance, 3x3 Spur Performance,

Image rejection and LO Buffer Output Power

RF SIGNAL

SOURCE

DC POWER

SUPPLY

RF IN

DUT

DC POWER

METER

IF OUT

LO IN

SPECTRUM

ANALYZER

LO SIGNAL

SOURCE

Figure 21. Test Bench Setup: Third Order Input Intercept Point (IIP3), 1dB

Blocking Point Measurements

RF SIGNAL

SOURCE

DC POWER

SUPPLY

DC POWER

METER

RF IN

RF SIGNAL

SOURCE

DUT

72 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

IF OUT

LO IN

SPECTRUM ANALYZER

LO SIGNAL

SOURCE

SWRA004A

Figure 22. Test Bench Setup: Noise Figure

NOISE FIGURE

METER

NOISE

SOURCE

DC POWER

SUPPLY

RF IN

DC POWER

METER

IF OUT

LO IN

DUT

Figure 23. Test Bench Setup: Power Leakage LO In to RF In

DC POWER

SUPPLY

DC POWER

METER

LO SIGNAL

SOURCE

SPECTRUM ANALYZER

RF IN

DUT

IF OUT

LO IN

Ω

LO SIGNAL

SOURCE

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 73

SWRA004A

Figure 24. Test Bench Setup: Power Leakage RF In to LO In Measurements

RF SIGNAL

SOURCE

DC POWER

SUPPLY

RF IN

DUT

DC POWER

METER

IF OUT

LO IN

Ω

Figure 25. Test Bench Setup: LNA Noise Figure Measurements

DC POWER

SUPPLY

DC POWER

METER

SPECTRUM

ANALYZER

NOISE FIGURE

METER

NOISE

SOURCE

RF IN

RF OUT

DUT

74 TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide

SWRA004A

Figure 26. Test Bench Setup: LNA Third Order Input Intercept Point (IIP3)

Measurement

RF SIGNAL

SOURCE

RF SIGNAL

SOURCE

DC POWER

SUPPLY

RF IN

DUT

DC POWER

METER

RF OUT

Figure 27. Test Bench Setup: LNA 1dB Input Compression Point

DC POWER

SUPLLY

DC POWER

METER

SPECTRUM ANALYZER

RF SIGNAL

SOURCE

RF IN

DUT

RF OUT

SPECTRUM

ANALYZER

TRF1500 Integrat ed Dual- B and RF Receiver User’s Guide 75

Texas Instruments TRF1500 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual