Slide 1 Fixture Measurements Doug Rytting. Slide 2 Agenda Agilent Network Analysis Applying the 8510 TRL Calibration for Non-Coaxial Measurements Product.

Slide 1

Fixture Measurements

Doug Rytting

Slide 2

Agenda

Agilent Network Analysis Applying the 8510 TRL Calibration for Non-Coaxial Measurements

Product Note 8510-8A

Agilent De-embedding and Embedding S-Parameter Networks Using a Vector Network Analyzer

Product Note 8510-8A

In-Fixture Measurements Using Vector Network Analyzers

Agilent AN 1287-9

OtherAsymmetrical Reciprocal OptimizationTwo-Tier Calibration and Simplified Error Models

Slide 3

Content of Application Note

TRL Calibration in Fixture

TRL Calibration on PC Board

Slide 4

Microstrip Test Fixture

Slide 5

Microstrip DUT in Fixture

Slide 6

Calibration Model

Slide 7

TRL Calibration Process

Slide 8

TRL Calibration Process Steps

Slide 9

Calibration Comparison

Slide 10

Calibration Comparison

Slide 11

PC Board TRL Calibration

Slide 12

PC Board vs Fixture

Slide 13

Time Domain of Launch and DUT

Slide 14

Agenda

Agilent Network Analysis Applying the 8510 TRL Calibration for Non-Coaxial Measurements

Product Note 8510-8A

Agilent De-embedding and Embedding S-Parameter Networks Using a Vector Network Analyzer

Product Note 8510-8A

In-Fixture Measurements Using Vector Network Analyzers

Agilent AN 1287-9

OtherAsymmetrical Reciprocal OptimizationTwo-Tier Calibration and Simplified Error Models

Slide 15

Content of Application Note

De-embed Process

De-embed using ADS models

Slide 16

Text Fixture

Slide 17

Fixture Model

Slide 18

Definition of T-Parameters

Slide 19

S-Parameters and T-Parameters

Slide 20

Combine Fixture and NA ModelsCombing a Two-Tier Calibration

Slide 21

Definition of Error Terms

Slide 22

Definition of Error Terms

Slide 23

Fixture Model Using:Lossy Transmission Lines

Slide 24

Model of Coax to Microstrip Transition

Slide 25

Complete ADS Model of Test Fixture

Slide 26

Measured vs Modeled FixtureOptimize until Modeled Matches Measured

Slide 27

S11: De-embedded vs Coax CalibrationSurface Mount Amplifier

Slide 28

S21: De-embedded vs Coax CalibrationSurface Mount Amplifier

Slide 29

Agenda

Agilent Network Analysis Applying the 8510 TRL Calibration for Non-Coaxial Measurements

Product Note 8510-8A

Agilent De-embedding and Embedding S-Parameter Networks Using a Vector Network Analyzer

Product Note 8510-8A

In-Fixture Measurements Using Vector Network Analyzers

Agilent AN 1287-9

OtherAsymmetrical Reciprocal OptimizationTwo-Tier Calibration and Simplified Error Models

Slide 30

Content of Application Note

Practical Considerations for Fixture Calibrations.

Time Domain Used to Reduce Errors.

Slide 31

Typical R&D Fixture

Slide 32

Direct Measurement Using Calibration

Slide 33

Two-Port Calibration

Slide 34

Determining Open Capacitance

Slide 35

Load Standard

Slide 36

Thru Standard

Slide 37

TDR Basics

Slide 38

TDR Basics

Slide 39

GatingThe gating may include the launches by mistake.

Slide 40

Optimizing Load

Slide 41

Connectors on Fixtures

Slide 42

Connector Performance

Slide 43

Agenda

Agilent Network Analysis Applying the 8510 TRL Calibration for Non-Coaxial Measurements

Product Note 8510-8A

Agilent De-embedding and Embedding S-Parameter Networks Using a Vector Network Analyzer

Product Note 8510-8A

In-Fixture Measurements Using Vector Network Analyzers

Agilent AN 1287-9

OtherAsymmetrical Reciprocal OptimizationTwo-Tier CalibrationSimplified Error Models

Slide 44

Asymmetrical Reciprocal Optimization

A passive asymmetrical reciprocal device is used in addition to short, open, load, and thru standards.The errors in calibration kit parameters can be reduced through numerical optimization to minimize asymmetry after correction. There are some potential convergence issues.

Slide 45

Asymmetrical Device

Slide 46

Before and After Optimization

Slide 47

Transmission Line Optimized Calibration

Measure S21m of a long transmission line.

Calculate S11c=S21mS21m of the transmission line.

Measure S11m of the transmission line with short connected to the end.

Subtract S11c from S11m for comparison.Adjust capacitance of open to minimize ripple.Adjust inductance of load and short to match the calculated S11c and measured S11m of the transmission line.

If possible, connect the load on the end of the long transmission line and adjust inductance of the load model for best performance. Then adjust the open and short models using a short connected to the end of the long transmission line.

Slide 48

Transmission Line Optimized Calibration

Coax example using a 10 cm verification airline with a short on the end.

Before and after optimizing the calibration standard’s models.

Same approach can be used for fixture and on wafer measurementsusing a long verification transmission line.

Slide 49

Two-Tier CalibrationFirst tier calibration stored in network analyzer.

Second tier calibration performed with first tier calibration turned on.

First tier could be SOLT and second tier TRL. This method enables TRL calibration on a 3 receiver NA.

First tier could be at coax port of NA and second tier at ports of a fixture This process will characterize the fixture.

Slide 50

Simplified Error Model for FixtureUsing Two-Tier Technique

Allows simpler second tier calibrations since number of error terms reduced from 7 to 6 due to reciprocity of the fixture.For example, SOLT can be simplified to SOL since no thru is required.Once fixture is characterized the data can be stored and used in future calibrations. Many other simplified fixture calibrations are available.