Low noise amplifier saturation

Thread Starter

musabfarooq

Joined Mar 22, 2017
38
Hi guys,

Suppose I feed two signals with different frequency and power to an amplifier.The power of one signal is high enough to make amplifier saturated. other signal is a low powered signal.
I am assuming that the amplifier will clip the high power signal and the low powered signal will remain unchanged. Am I right or both signal will be clipped ?

Regards
 

ericgibbs

Joined Jan 29, 2010
12,927
hi m,
With an ideal amplifier the high level signal will saturate the amp and the low level signal would not be visible on the output during the saturated periods.
E
What is the application.?
 

Thread Starter

musabfarooq

Joined Mar 22, 2017
38
hi m,
With an ideal amplifier the high level signal will saturate the amp and the low level signal would not be visible on the output during the saturated periods.
E
What is the application.?
We are working on the receiver of SDR. The problem we are trying to solve is adjacent channel rejection. Lets suppose the interferer signal is very strong and our valid signal is week. The strong interferer signal will saturate the LNA's in our receiver. What I am hoping is that after filtering the interferer at output, I get the unchanged valid signal.
 

danadak

Joined Mar 10, 2018
4,057
Filtering in the case of saturation will not work in this example.

Filtering has to take place at input of amp. Your filter, proposed at output,
has no knowledge of what the input signals look like because, as you say,
the amp has saturated. The filter cannot "predict" what the input conditions
in the signal chain look like because it is being fed a saturated signal that no
longer has signal properties of input. It is no longer an LTI system.


Regards, Dana.
 
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