Dear All,

I am using the pfb_clock_sync to estimate the timing offset in my QPSK
receiver and I have a problem that I would like to ask about.

Basically if the amplitude of the incoming signal is set relatively high
(havent checked what actual threshold is) the flowgraph just hangs. After
the process of elimination I discovered that it is actually the
pfb_clock_sync block that causes this. Then I put some printf statements in
the code and found out that the d_k (phase) value becomes -NaN when signal
amplitude becomes high. The same thing is with the d_error from
here d_error = (error_i + error_r) / 2.0.

I suspect it is due to some filtering (either the RC or diff filter).

Do you have any suggestions on where this might be coming from?

Any comments will be highly appreciated.

Many thanks,

Kind Regards
Discuss-gnuradio mailing list

Reply via email to