About digital predistortion(DPD) power amplifier!

[zhl_gs1980]

Hi:

Anyone knows how to extract the PA's model and how to build LUT from PA model?

Thanks in advance!!

 

[zhl_gs1980]

HELP!!

 

[radiohead]

It depends on the modulation you're using. Typically you can start from a simplified measurement model based on the AM/AM and AM/PM curves of the amplifier. For example if you know that you loose 0.5 dB for the bigger amplitude from the constellation, you compensate that by driving the amplifier with 0,5 dB extra. Same goes for phase distortion.

For some modulation formats both AM/AM and AM/PM are important (eg 64-QAM), for other only phase distortion is important (GMSK e.g.).

 

[zhl_gs1980]

Thanks, radiohead!

If I know the PA's model (eg: Saleh's model) and its detailed parameters, and how I bulid LUT(Complex-gain based)?

 

[zhl_gs1980]

up!!!

 

[ahmain]

Hi everybody.
I have a question about DPD. Is knowing adaptive filter necessary for do DPD? or we can just use final result of adaptive filter? how about parameter estimation
of model? how can I estimate parameter of model? please help me. Thank you for your thought about this subject.