Hi, I recently triy to receive ibeacon signal whose modulation scheme is GFSK, so I use the /gfsk_demod/ block in gnuradio and succeed to demodulate ibeacon signal. Yet I don't understand the meaning of some of its parameters and why these parameters are assigned to some certain values. For example, the parameter /gain_mu/ is set to 0.175 as default.
I then read the codes of /gfsk_demod/ and find that there is actually one step of clock recovery there. Then I read the papers cited by the documentation of /gfsk_demod/ block and learn the principle of the digital clock recovery algorithm used in it. As far as I know, the Mueller and Muller algorithm uses linear combination of samples to estimate the timing error, which is then used to adjust the sampling phase. So the parameter /omega/ is the estimate of timing shift caused by carrier frequency shift, the parameter /mu/ is the estimate of final timing shift, and /gain_omega/ and /gain_mu/ are weights of estimate of timing error when adjust respective parameters, is it correct? Then the last question is how are these parameters assigned? For example, /gain_mu/ is set to be 0.175 and /gain_omega/ is set to be 0.25*/gain_mu/*/gain_mu/. Are these assignment related to any previous works or derivatives or some experiments or simulations? Do these values have any special meaning? Thanks, Kun Qian -- View this message in context: http://gnuradio.4.n7.nabble.com/How-are-parameters-of-gfsk-demod-block-assigned-tp49734.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
