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[Discuss-gnuradio] frequent phase slip with the new digital.costas_loop_
[Discuss-gnuradio] frequent phase slip with the new digital.costas_loop_cc
Thu, 20 Sep 2012 23:56:00 +1000
I adapted my codes from gnuradio-3.3 to the new 3.6 version.
One of the changes is the new digital.costas_loop_cc is now implemented based
The costas loop is used for phase recovery of a QPSK signal.
But I noticed that with the new version, the output experiences a lot of phase
To be exact, the phase at the output rotate 90 degree from time to time.
I changed it back to the old gr.costas_loop_cc and this did not happen.
The setting for the old loop is alpha=0.01, beta=alpha*alpha/4,
The setting for the new loop is loop bandwidth = 2*pi/100
The new version is only good when SNR is very high, say 13dB+
Any has encountered the same problem? or am I doing something wrong?
- [Discuss-gnuradio] frequent phase slip with the new digital.costas_loop_cc,
Kyle Zhou <=