Re: No filters in the receive path on FMCOMMs1?

Hi, Charly

    In my project, FMCOMMs1 will capture the signal from air, the target bandwidth for use is 600MHz~3.0GHz. The Rx Frequency will change from 2.97GHz, to 2.91GHz, 2.85GHz, 2.79GHz, 2.73GHz, ... 690MHz, 630MHz. For each time, FPGA will storage 60MHz bandwidth spectrum data around RX Frequency. After 40 times capture, FPGA get 40*60MHz = 2.4GHz bandwidth spectrum signal from 3GHz to 600MHz.

     I do the test as below:

     step1: I use a USRP to keep sending a 18MHz bandwidth OFDM signal to the air whose Center Frequency is 1.3GHz. And I use a spectrum analyzer to check it that there is only a 18MHz bandwidth signal in 1.3GHz in the range of 1.0GHz ~ 1.6GHz.

     step2: The attachment is part of the data within the range of 600MHz ~ 3GHz, which is about 1.0GHz~1.6GHz, resulting from my project.

     We can see that there are many harmonics, the distance between harmonics is about 81.92MHz. By the way, the sampling rate is 81.92Msps in my project.

     Thanks.

Zhonghua