Hi Marcus and Adrian, Apologies for the incorrect link to the private image. You are correct, the diagram in the README.md is the proper one. Thanks a lot for your advice.
For now, I've tried the simplest solution — adding a "Simple Squelch" block to feed the "Polyphase Clock Sync" only when a signal is present. The updated schematic is now available in the README.md of the project on GitHub: https://github.com/yabool2001/BPSK_test_02_3 Unfortunately, it didn't help. In this configuration, the project only works with a continuous source, such as "Constant Source". If there is a better implementation for signal detection that could assist in burst transmission, I'd be grateful for your recommendation. Now, I will also try Adrian’s suggestion to implement the "Correlation Estimator" block. Thanks again for your support! Best regards, Yabool2001 pon., 12 maj 2025 o 14:51 Marcus Müller <mmuel...@gnuradio.org> napisał(a): > Hi Maciej, > > sadly, you attached a link to a picture on > https://private-user-images.githubusercontent.com… , which is > github-account-specific and > can't be used by anyone but you. But the raw URL in your Readme works, > > https://github.com/user-attachments/assets/3f9eee70-811e-41be-9d43-877b2dcbb078 > so I'm assuming that's the one. > > What I think is wrong here is that the Polyphase Clock Sync drifts off > during the pauses > between frames: it doesn't know whether it's looking at noise only or > signal, and so tries > to "wildly" guess what it should do during the "noise only" periods, just > to then be off > from the correct timing enough to not be able to catch up with it during > the first few > symbols of each frame. > > In a practical system, you'd need to first detect presence before you feed > it through the > clock synchronizer. > > Best regards, > Marcus > > On 5/12/25 10:47 AM, Maciej Zemło wrote: > > Hi everyone, > > > > I've developed a brief demonstration project in GRC that transmits a > single byte via Pluto > > using BPSK modulation. The project works well when using a "Constant > Source" block that > > continuously sends the byte, but it completely fails to function with > the "Message Strobe" > > block, which sends a byte every 0.5 seconds. > > > > The project is available on GitHub for further reference: > https://github.com/yabool2001/ > > BPSK_test_02_3 <https://github.com/yabool2001/BPSK_test_02_3> > > > > I've attached a screenshot illustrating the structure of the project, > available here > > <https://private-user- > > > images.githubusercontent.com/38382353/442661233-3f9eee70-811e-41be-9d43-877b2dcbb078.png? > > > > jwt=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.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.whxllXKHs55LV7wgcRfq7BPy3oQjAiGJWUoKc-J8en8>. > > > > Could someone point me in the right direction regarding what might be > going wrong here? > > > > Thanks in advance for your assistance! > > > > Best regards, > > Yabool2001 > > > > >
