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Slide 1 Network Analyzers From Small Signal To Large Signal Measurements Doug Rytting

Network Analyzers From Small Signal To Large Signal Measurements

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Network Analyzers From Small Signal To Large Signal Measurements. Doug Rytting. Agenda. Small Signal Measurements & Error Correction Compression and AM to PM Hot S22 Measurements Load Pull Measurements Pulse Measurements Large Signal Network Analyzer Measurements. - PowerPoint PPT Presentation

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Page 1: Network Analyzers From Small Signal To Large Signal Measurements

Slide 1

Network AnalyzersFrom Small Signal

To Large Signal Measurements

Doug Rytting

Page 2: Network Analyzers From Small Signal To Large Signal Measurements

Slide 2

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 3: Network Analyzers From Small Signal To Large Signal Measurements

Slide 3

RFSource

LOSource

a0

b0 b3

Port - 1 Port - 2

a3

DUTa2

a1

b1

b2Cable Cable

IF

IF

IF

IF

Network Analyzer Block Diagram

Page 4: Network Analyzers From Small Signal To Large Signal Measurements

Slide 4

ERRORS REMOVED ERRORS REMAINING

Noise and Residuals

Receiver Linearity

Drift after Error-Correction

Stability after Error-Correction

Repeatability of Connectors, etc

Lower Lever Leakage Paths

Errors of Calibration Standards

Port Match

Directivity

Tracking

Main Leakage Paths

Improvements with Correction

Page 5: Network Analyzers From Small Signal To Large Signal Measurements

Slide 5

Improvements with Correction

Page 6: Network Analyzers From Small Signal To Large Signal Measurements

Slide 6

TRL & LRL

TRM & LRM

TraditionalTOSL

(Overdetermined)

LRRM

UXYZUnknown Thru

TXYZ & LXYZ

Thru (T) or Line (L) withknown S-parameters

[4 conditions]

Unknown Line (U) withS 12 = S 21

[1 condition]

Line (L) with knownS 11 and S 22

[2 conditions]

Known Match (M)on port-1 and port-2

[2 conditions]

3 known Reflects (XYZ)on port-1 or port-2

[3 conditions]

3 known Reflects (OSL)on port-1

[3 conditions]

Known match (M)on port-1

[1 condition]

3 known Reflects (XYZ)on port-1

[3 conditions]

2 unknown equal Reflects(RR) on port-1 and port-2

[2 conditions]

3 known Reflect (OSL)on port-2

[3 condition]

Unknown equal Reflect (R)on port-1 and port-2

[1 condition]

Seven or more independent known conditions must be measuredA known impedance (Z 0) and a port-1 to port-2 connection are required

Line (L) with knownS-parameters[4 conditions]

Thru (T) or Line (L) withknown S-parameters

[4 conditions]

Thru (T) or Line (L) withknown S-parameters

[4 conditions]

Thru (T) withknown S-parameters

[4 conditions]

Unknown equal Reflect (R)on port-1 and port-2

[1 condition]

3 known Reflects (XYZ)on port-2

[3 conditions]

Calibration Examples – 8 Term Model

Page 7: Network Analyzers From Small Signal To Large Signal Measurements

Slide 7

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 8: Network Analyzers From Small Signal To Large Signal Measurements

Slide 8

Saturated output power

Outp

ut

Pow

er

(dB

m)

Input Power (dBm)

Compression region

Linear region (slope = small-signal gain)

Power Sweep - Compression

Page 9: Network Analyzers From Small Signal To Large Signal Measurements

Slide 9

0

CH1 S21 1og MAG 1 dB/ REF 32 dB 30.991 dB 12.3 dBmC2

IF BW 3 kHz SWP 420 msecSTART 10 dBm CW 902.7 MHz STOP 15 dBm

0

1 dB compression: input power resulting in 1 dB drop in gain

Ratioed measurement Output power available (non-

ratioed measurement)

Power Sweep -Gain Compression

Page 10: Network Analyzers From Small Signal To Large Signal Measurements

Slide 10

1:Transmission Log Mag 1.0 dB/ Ref 21.50 dB

Use transmission setup with a power sweep Display phase of S21 AM - PM = 0.86 deg/dB

Start -10.00 dBm Stop 0.00 dBmCW 900.000 MHzStart -10.00 dBm Stop 0.00 dBmCW 900.000 MHz

2:Transmission /M Phase 5.0 deg/ Ref -115.7 deg

1

2

1

1

2

Ch1:Mkr1 -4.50 dBm 20.48 dB

Ch2:Mkr2 1.00 dB 0.86 deg

Power Sweep - AM to PM Conversion

Page 11: Network Analyzers From Small Signal To Large Signal Measurements

Slide 11

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 12: Network Analyzers From Small Signal To Large Signal Measurements

Slide 12

Hot S22 Measurement System

Small signal S-parameters of a nonlinear device in the presence of a high power drive signal f away from test frequency.

Osc

b 1

a 1 b 2

a 2

a3

b3

a b0 0

DUT[A]

High Power Load

High Power

Osc

High Power

Combine

Page 13: Network Analyzers From Small Signal To Large Signal Measurements

Slide 13

Hot S22 Measurement System

S-parameters of a nonlinear device at a defined input or output power.

OSCb 1

a 1 b 2

a 2

a3

b3

a b0 0

DUT[A]

A

B

Page 14: Network Analyzers From Small Signal To Large Signal Measurements

Slide 14

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 15: Network Analyzers From Small Signal To Large Signal Measurements

Slide 15

Need to measure nonlinear device behavior under actual operating conditions

Low power

High power

S 22

Constant output power contours versusoutput load impedance

Pmax

-1 dB

-2 dB

-3 dB

Parameter changes vesusoutput power level

Load Pull Measurement

Page 16: Network Analyzers From Small Signal To Large Signal Measurements

Slide 16

DUTX XX X

INPUTIMPEDANCE

ANDPOWER

MEASUREMENTSYSTEM

OUTPUTIMPEDANCE

ANDPOWER

MEASUREMENTSYSTEM

INPUTTUNER

OUTPUTTUNER

Load Pull System

Page 17: Network Analyzers From Small Signal To Large Signal Measurements

Slide 17

Harmonic load-pullPassive load-pull Active load-pull

Simultaneous Drive

OSC

DUT

Types of Output Tuners

Page 18: Network Analyzers From Small Signal To Large Signal Measurements

Slide 18

Harmonic Load Pull System

DUT

Four Channel Frequency ConverterHP 8510C/85110A

b 2a 1 a 2b 1

LO SynthesizerHP 8360

1 - 50 GHz

Port 1InputProbe

Port 2Output Probe

ReflectometerMounted on

Prober

T

T

Tfo 2fo 3fo

T

Source SynthesizerHP 8360

1 - 50 GHz

Port DrivePIN Switch

Input Amplifier 1 - 50 GHz TWA

Port 3Coaxial andpower cals.

LO SynthesizerCan be Tunedto Harmonics

Page 19: Network Analyzers From Small Signal To Large Signal Measurements

Slide 19

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 20: Network Analyzers From Small Signal To Large Signal Measurements

Slide 20

High Power Device Pulse Measurements

Control DUT TemperatureEliminate temperature as a variableTest high power devices on-wafer at full power Measure devices in "unsafe" DC operating area

Test "pulsed" devices in a pulsed environmentTest environment = final application (GSM) Pulsed radars/phased array antennas/high power MMIC's

Improve device characterization dataModel power FET's at full power levelMeasure IV curves without temperature effectsInvestigate trapping effects in GaAs

Page 21: Network Analyzers From Small Signal To Large Signal Measurements

Slide 21

Pulse System Capabilities

Synchronization of pulses

IV plane characterization

Point in pulse vs Frequency or Pulse profile vs Time

Gate/Base

Drain/Collector

RF

RF PW

T1

T2

ID

VD

Q1

Q2

DC Safe Operating Limit

Page 22: Network Analyzers From Small Signal To Large Signal Measurements

Slide 22

Pulsed Bias/RF Meas System

Network Analyzer MeasurementController

Drain / CollectorBias Pulser

Gate / BaseBias Pulser

DC Power Supply

Pulse Generator

Digital Multimeter

Pulsed-RFTest Set

RF Synthesizer

LO Synthesizer

Bias Network

T

Trigger

T

T

T

T

T

Page 23: Network Analyzers From Small Signal To Large Signal Measurements

Slide 23

Agenda

Small Signal Measurements & Error Correction

Compression and AM to PM

Hot S22 Measurements

Load Pull Measurements

Pulse Measurements

Large Signal Network Analyzer Measurements

Page 24: Network Analyzers From Small Signal To Large Signal Measurements

Slide 24

Complete SpectrumWaveforms

Harmonics and Modulation

Large Signal Network Analyzer

Acquisition (LSNA)

Stimulus

Response

ESG 50 Ohmor

Tuner

Page 25: Network Analyzers From Small Signal To Large Signal Measurements

Slide 25

Large Signal Network Analyzer

Measures magnitude and phase of incident and reflected waves at fundamental, harmonic, and modulation frequencies.Calibrated for relative and absolute measurements for both linear and nonlinear components at the device under test.Calculate calibrated voltage and current in both the time and frequency domains.

Combination of a vector network analyzer, sampling scope, spectrum analyzer and power meter.

Page 26: Network Analyzers From Small Signal To Large Signal Measurements

Slide 26

LSNA System Block DiagramSampler Front End

Requires high BW IFRequires Harmonic LO

Page 27: Network Analyzers From Small Signal To Large Signal Measurements

Slide 27

Sampling Converter Fundamentals

LP

Freq. (GHz)1 2 3

50 fLO 100 fLO 150 fLO

Freq. (MHz)1 2 3

RF

IF

fLO=19.98 MHz = (1GHz-1MHz)/50

IF Bandwidth: 4 MHz

Page 28: Network Analyzers From Small Signal To Large Signal Measurements

Slide 28

LSNA System Block DiagramMixer Front End

Requires harmonic syncCan use high BW IF for modulationOr low BW IF if no modulation

Page 29: Network Analyzers From Small Signal To Large Signal Measurements

Slide 29

Nonlinear Calibration - Model

Measured wavesActual waves at DUT

7 relative error termssame as a VNAAbsolute magnitude

and phase error term

50 Ohmor

Tuner

AcquisitionStimulus

Response

ModulationSource

0a 0b 3a 3b

1a 2a

1b 2b

Page 30: Network Analyzers From Small Signal To Large Signal Measurements

Slide 30

Nonlinear Calibration

Relative calibration at the fundamental and harmonic frequencies determines the 7 normal error terms.

Power calibration at the fundamental and harmonic frequencies determines the magnitude of K.

Phase reference generator calibration determines the phase of K relative to the fundamental frequency.

Reference generator is an impulse that must be accurately modeled or measured.

Page 31: Network Analyzers From Small Signal To Large Signal Measurements

Slide 31

Example # 1

Complete device measurement capability using a Large Signal Network Analyzer (LSNA).

Page 32: Network Analyzers From Small Signal To Large Signal Measurements

Slide 32

Device Measurement

)(1 ta )(1 tb

)(2 ta )(2 tb

)(1 tv

)(1 ti

)(2 tv

)(2 ti dsv

dsi

-1.2 V

-0.2 V

MHzf 9000

50 Ohm loadOpen port

gv

Page 33: Network Analyzers From Small Signal To Large Signal Measurements

Slide 33

Example # 2

Device measurement verification and measurement-based model improvement.

Page 34: Network Analyzers From Small Signal To Large Signal Measurements

Slide 34

MODEL TO BE OPTIMIZED

generators apply LSNA measured waveforms

“Chalmers Model”

“Power swept measurements under mismatched conditions”

GaAs pseudomorphic HEMTgate l=0.2 um w=100 um

Parameter Boundaries

Model Verification & Improvement

Page 35: Network Analyzers From Small Signal To Large Signal Measurements

Slide 35

During OPTIMIZATION

Time domain waveforms Frequency domaingate drain

voltage

current

gate drain

Voltage - Current State Space

Model Verification & Improvement

Page 36: Network Analyzers From Small Signal To Large Signal Measurements

Slide 36

Model Verification & Improvement

Time domain waveforms Frequency domaingate drain

voltage

current

gate drain

Voltage - Current State Space

After OPTIMIZATION

Page 37: Network Analyzers From Small Signal To Large Signal Measurements

Slide 37

Vector Network AnalyzerReferences

Page 38: Network Analyzers From Small Signal To Large Signal Measurements

Slide 38

Large Signal Network Analyzer References