AnsweredAssumed Answered

Why strange spectrum occurs when Input frequency=LO frequency

Question asked by CDRFT Employee on Mar 28, 2016
Latest reply on Mar 29, 2016 by CDRFT

Hi, My friend

When I tested the demo board of AD9361, I found a strange issue:

When input signal frequency = LO frequency:

1. For AGC mode, if BB DC tracking=ON, some times the noramal spectrum become strange one;

2. For AGC mode, if BB DC tracking=OFF, the strange spectrum never happen;

3. For MGC mode, no matter BB DC tracking=ON/OFF, the strange spectrum never happen;

 

My question is :

Why BB DC tracking enbale will cause such strange spectrum when the frequency of input signal=LO frequency in AGC mode?

 

Thanks~

 

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