I’m learning to implement a grc flow-graph with BPSK modulation to send and receive text/image file or send chat message via UDP socket. It’s working in simulation mode perfectly as I intended but with real hardware obviously lot of issues are happening.
Initially, I was receiving only garbled data with limesdr-mini but after further reading I found that’s due to phase ambiguity problem in the receiver. Then I used differential encoding to resolve the issue. If I sent a text file in repeat mode, I can receive it on file sink.
However, If I sent the file only once without repeat, I don’t get any data at all. I understand that the receiver perform clock, frequency, phase recovery on received data and when it sync, it decodes the data correctly.
TX and Rx constellation:
Can somebody shed some light what I’m missing here. In simulation, this flow graph works correctly with text/image transfer and chat messaging (UDP Source/Sink).
What measures I have to consider further to make it work the same way with LimeSDR.
Appreciate any suggestions