[Discuss-gnuradio] BPSK/QPSK transmission using GNURadio Companion with

Hello everyone,

I am trying to implement a BPSK/QPSK transmission chain using GNURadio Companion. I have succeeded to make it work well in simulation, but now I am having some trouble when using the AD9361/ZC706 boards.

As a first try, I just connected a loopback cable between TX1A and RX1A. I am using GRC 3.7.13.4 with IIO support, and I use the FMComms2/3/4 Source and FMComms2/3/4 Sink to communicate with the boards.

When I am doing a transmission, the receiver side has some « glitches » : It stops receiving for a short time, and then restarts receiving the sent signal. I have linked four screenshots about the block configurations (fm_sink.PNG,fm_source.PNG) and the issue (reset_tx.PNG,reset_rx.PNG). I think it is linked to GNURadio since I don’t observe this behaviour when I transmit a single CW tone using IIO-Oscilloscope.

Normally, I should use a larger bandwidth (around 4 MHz) and a higher sampling rate (around 16 Msps), but the problem occurs more likely when I increase the sampling rate.

Does someone have any idea about something I could have badly or not configured ?

Thank you in advance,

François DSM

From:	Francois De Saint Moulin
Subject:	[Discuss-gnuradio] BPSK/QPSK transmission using GNURadio Companion with AD9361/ZC706 boards
Date:	Wed, 7 Aug 2019 09:08:46 +0000