Hi everyone, how are you? Hope you’re doing fine. I’m working to use the LimeSDR to perform (time varying) phase measurements. I would like to ask the community and also the LimeSDR team (@andrewback, @Zack, @joshblum, etc.) what are the considerations that I have to take into account about the LimeSDR configuration to do such a task.
Let’s suppose the concept shown in this figure:
Ideally, In the Tx side, the lime transmits (for example) a pure sinusoid with a frequency , so the signal that enters in the Rx side will be:
The first thing I tried to do is to transmit the sinusoid with the test signal (DC Source in TxTSP) in TDD Mode. Here (if i’m not mistaken), the PLL that synthetize the Tx Signal is the same at the Rx side, trying to make coherent detection. In this case, the samples retrieved by the lime will be, Q(t)+j I(t). I can obtain the phase doing atan[I(t)/Q(t)] or another DSP. This is not working and I don’t know what i’m missing. I’m only obtaining noise.
Thanks in advance,
Lucas.