PN correlator stucks when degree larger than 6?

General Discussion
1

I am running a simple flowgraph, just to learn how to use “PN correlator”. If the degree of GLSFR and PN correlator is no larger than 6 the system works and quickly displays results.. But if I set degree=7, GNURadio never shows results and freezes.

The problem seems to be due to PN correlator block, because if I disable it everything works.

I am running GRC 3.10.12.0 (Python 3.12.3).

Any help?

Regards

Piero

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2

I think the problem might be that you are sending different rate streams into the same “Time sink” block.
PN correlator decimates the input by (1 << degree), so you end up with one stream of 100k samples, and the PN correlator output of 100000 / (1 << 6) = ~1500 samples. Resulting in Time sink block freezing while waiting for equal amount of data for both inputs.
You should use separate time sinks just like in the example: PN Correlator - GNU Radio

3

Thank you very much! Following your suggestion I was able to run my example without problems, as you can see from the screenshot below.

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