High power microwave power amplifier measurement

[nccu1990]

Dear All:

I have a friend .He want to measure the s-parameter of S-band (2GHz - 4GHz) power amplifier under 100Watt.

But he afraid that any step which is incorrect , it will destroy the VNA.

I suggest that he use the high power attenuator to protect the VNA. But the VNA cal procedure have many issue which i don't know.

Can you share your experience and idea for high power amplifier measurement?

Thank you.

 

[RF-OM]

You need to do standard SOLT calibration with power attenuator included. This will put calibration planes on the ends of connectors and you may measure your amplifier.

 

[khouly]

yeah , i agree with RF-OM. this is the way to calibrate ur network analyzer

Khouly

 

[nccu1990]

I search some document from the google,
the VNA calibration setup is complex.

Some setup need to use the direct generator and receiver access at the VNA.

So I don't sure that my friend can do the correct high power amplifier measurement.

 

[RF-OM]

Yes, there are some more complicated methods, but I told you about the simplest one. The best is to search Agilent Application Notes. There you may find detailed description how to use VNA with power amplifier. Calibration procedure with attenuators is not absolutely perfect because it change the directivity for ports, but usually it provide good results and it is practically the same as standard SOLT calibration. The only difference is that now attenuator or attenuators included bee tween port(s) and calibration planes.