AnsweredAssumed Answered

How to eliminate the out of bandwidth signal?

Question asked by RobertYJ on Jun 19, 2018
Latest reply on Jun 22, 2018 by srimoyi

Hi everyone,


I am using AD9361 FMCOMMS3 to sent a 9 MHz DDS signal, and baseband sample frequency is 20MHz.


Below is my settings.


Spectrum is as follow, you can see that there has a peak at -11 MHz from central frequency, I think this is due to my sample frequency is 20 MHz, so there has a peak at -20 MHz + 9 MHz = -11 MHz.


My question is how to eliminate that peak at -11 MHz, or how to decrease the power to less than -50 dB?


Thanks a lot.


p.s. Attachment is the spectrum diagram.