how to measure the AM to PM characteristic of RF PA?

dear all.

Who can tell me how to measure the AM to PM characteristic of the RF power amplfier? which test equipment is needed for this ?

I know the AM to AM characteristic is the PA's gain.

loverrf

Hi.

Using Tektronix RSA3408, you can evaluate AM/AM and AM/PM characteristics for actual modulation signal.

See following datasheet.

http://www.tek.com/Measurement/App_N...7W_18526_0.pdf

You can use a Vector Network Analyzer using Power Sweep for input power and read the phase change at the output of the PA.
Do not forget to place an attenuator at the output of the PA to don?t damage the input of the VNA.

Calibrate the power before frequency(full two ports)