Check the cutoff frequency and transition frequency on the rx filter. That's not what you want, and it's unlikely your computer can run a filter that tight at 8MS/s in real time.
On Wed, Apr 19, 2023, 12:03 יותם זיס <[email protected]> wrote: > Hello, we're students trying to build an S-Band BPSK modem. > Transmitting using UHD-USRP b200 and receiving with Lime-SDR Mini. > > We have a problem when working with a high bitrate, 1Mbps with 8 sps: > Only one point is showing up in the constellation. When we worked in > 9600bps it worked just fine. > In addition we're also using gr-lfast blocks to make it possible to run > our program without maxing out the CPU. > > Attached screenshots of our uplink and downlink flowgraphs and the GUI. > > Thanks and 73 >
