VNA Calibration - 12 Error Term model

Hello, I have an Advantest R3762 VNA which has an annoying feature of requiring the calibration data to be reloaded from a floppy each time the thing is started. I have decided that I wish to use an excel macro to calibrate the machine and store the results in an SQL database. I am currently in the process of writing the VBA logic but the attached extract from "Microwave Component Measurements" troubles me.

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Page 132, states that all VNAs have in built models for the reflection standards, Short, Open, Load. Basically I measure the standards, then the VNA compares the measured values with its inbuilt models to determine what sort of correction is required.


I will require these models if I am to write the calibration logic. Does anyone know where I can find the models?

What if I measure the standards attached directly to the VNA ports and take these values as the Actual reflection standards. Then I attach the cables and VNA reflection standards and determine the Measured reflections. From these measurements I can then determine the calibration error terms. What do you think? Would this be accurate?

Any better ideas?



Thank you

Maybe look for "Applying Error Correction to NWA Measurements" from Agilent. Maybe it will help!

This application note will definitely help you:
"Specifying Calibration Standards and Kits for Agilent Vector Network Analyzers"

I assume you have the formulas for performing the 12 error-term calculations?