"Impedence matching methods" for power amplifier

Thee are different methods of impedance matching for the power amplifier.

PA impedance matching techniques
a. Load pull methods
b. Cripps method

1. I know Load pull method, by varying output load impedance I check that "Delivered power" or "Power added efficiency" to get maximum based on my goal. remember that in ADS or some definitions it is mentioned that for each load, input matching is also performed to maximize power delivery from input to output.
2. Cripps method: I don't get it even I search the Google or check the book "RF power amplifier for wireless communication".

What I understood from cripps method?
By load line I calculate R_opt then by varying "X" in this formula : Z_L = R_opt ± j*X

we check which value is the best for maximum "power delivered" or "PAE".

Am I right?

P.s
Do we have other methods for impedance matching?

"Load Pull Method" has been accepted by industry and RF Engineering.

Transformers
Transformers are sometimes used to match the impedances of circuits.


Filters
Filters are frequently used to achieve impedance matching in telecommunications and radio engineering. In general, it is not theoretically possible to achieve perfect impedance matching at all frequencies with a network of discrete components.


L-section
A simple electrical impedance-matching network requires one capacitor and one inductor. One reactance is in parallel with the source (or load), and the other is in series with the load (or source). If a reactance is in parallel with the source, the effective network matches from high to low impedance. The L-section is inherently a narrowband matching network.

Thanks for replies but anyone answered the main question.
How is the Cripps method for impedance matching?

Is the following description about Cripps method true?
"By load line I calculate R_opt then by varying "X" in this formula : Z_L = R_opt ± j*X
we check which value is the best for maximum "power delivered" or "PAE"."
is it Cripps method?
and 2nd question: in Cripps method when input match is done? do we first do input match then output match or vice verse? (Obviously I am assuming transistor is to be bilateral)

MamadJun said:

Thanks for replies but anyone answered the main question.
How is the Cripps method for impedance matching?

Is the following description about Cripps method true?
"By load line I calculate R_opt then by varying "X" in this formula : Z_L = R_opt ± j*X
we check which value is the best for maximum "power delivered" or "PAE"."
is it Cripps method?
and 2nd question: in Cripps method when input match is done? do we first do input match then output match or vice verse? (Obviously I am assuming transistor is to be bilateral)

Click to expand...

There are different needs for Power Amps, so you can match them in different ways to achieve you deign requirements.

i.e. If you are doing FSK, FM, or PSK you can use a Class C amp and intend to drive it to it's -1dB compression point.
For this you can use a load pull test to find the best match to get Max Pout.

But,
If you want to use the same PA to be used in it's linear region (Class A or A/B) then you would want to do more of a
Conjugate Match.