Limesdr Mini Receiver problem

General Discussion
5

Hi @jpatel197,

I’m not sure, but it seems an expected result.

Since you use the same frequency for Tx and Rx and operate with a continuous wave, the received signal most likely is removed by the Rx DC canceler: https://wiki.myriadrf.org/LimeMicro:LMS7002M_Datasheet#RX_DC_correction .

I have the same result on my LimeSDR USB and I did the following tests to prove my assumption:

  1. Instead of the CW signal I transmit a pulse one with a period about 1ms and a various duty cycle, and I can see the signal until a duty cycle is greater or equal about 99%.
  2. I set a slightly different frequency for the Rx channel (-/+ about 1kHz) and in this case, I also can see the signal (with a beating frequency: https://en.wikipedia.org/wiki/Beat_(acoustics) ).
  3. I was going to disable the Rx DC canceler and check an input signal, but so far I don’t know how to do it.

Also, I found a topic with a similar issue: Easiest way to transmit CW frequency and measure received IQ? .