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Design >> RF Design >> power match and conjugation match in pa design.
https://designers-guide.org/forum/YaBB.pl?num=1246435268

Message started by waseda-rfic on Jul 1^st, 2009, 1:01am

Title: power match and conjugation match in pa design.
Post by waseda-rfic on Jul 1^st, 2009, 1:01am

now, my pa output power and PAE is very good and high pass architecture is used for output match circuit . but the S22 is very bad, only -3. and if i optimize the S22, the output power and PAE become very bad. so how to solve this problems? should I change the output match architecture?

Title: Re: power match and conjugation match in pa design.
Post by waseda-rfic on Jul 1^st, 2009, 6:23pm

no one meet this problem before?

Title: Re: power match and conjugation match in pa design.
Post by pancho_hideboo on Jul 1^st, 2009, 8:23pm

Hi, meiji-rfic.

waseda-rfic wrote on Jul 1^st, 2009, 1:01am:

now, my pa output power and PAE is very good and high pass architecture is used for output match circuit.
but the S22 is very bad, only -3. and if i optimize the S22, the output power and PAE become very bad.
so how to solve this problems? should I change the output match architecture?

If feed line is short to next stage or antenna, we can accept bad S22, e.g. -3dB.
But if feed line is long, you have improve S22 or insert lossy matching pad after your PA.

More importanty rather you have to consider load stablity and load survivablity for your PA.

Title: Re: power match and conjugation match in pa design.
Post by waseda-rfic on Jul 2^nd, 2009, 1:15am

pancho_hideboo wrote on Jul 1^st, 2009, 8:23pm:

If feed line is short to next stage or antenna, we can accept bad S22, e.g. -3dB.

after the PA, usually, a filter or the antenna is connected with the PA. will the bad S22 deteriorates the characteristic of the filter or the antenna ?

pancho_hideboo wrote on Jul 1^st, 2009, 8:23pm:

But if feed line is long, you have improve S22 or insert lossy matching pad after your PA.

More importanty rather you have to consider load stablity and load survivablity for your PA.

i know how to see the load stablity circle,but for the load survivablity, how can i simulation in ADS or Cadence?
thank you for your help!!