In the gmsk.py, the gr.clock_recovery_mm_ff is used.
I want to use gr.clock_recovery_mm_cc (float omega, float gain_omega, float mu, float gain_mu) (which implements Mueller and Müller (M&M) based clock recovery block with complex input, complex output) to replace the gr.clock_recovery_mm_ff
I have done these in two steps:
1. use the same parameters (used to init gr.clock_recovery_mm_ff) to init gr.clock_recovery_mm_cc.
omege=2.000000, gain_omega=0.000625, mu=0.050000, gain_mu=0.050000, omega_relative_limit=0.005000
2. move the clock recovery block forward before demod block
self.connect(self, self.clock_recovery, self.fmdemod, self.slicer, self)
Before modification, if I run the benchmark program using gmsk, receive rate is almost 100%, but after my modification, receive rate drops to 0%.
Does my method have problem, any help is appreciated!