Hi everybody, I am implementing a GMSK demodulator. To achieve coherent demodulation, I recovered the frequency with the power of 4 of the signal. How can I recover then the phase? Can anybody give me any clue? Thanks mj
phase recovery
Started by ●September 3, 2008
Reply by ●September 3, 20082008-09-03
On Sep 4, 1:10 am, "m" <stuttbr...@hotmail.com> wrote:> Hi everybody, > > I am implementing a GMSK demodulator. To achieve coherent demodulation, I > recovered the frequency with the power of 4 of the signal. How can I > recover then the phase? Can anybody give me any clue? > > Thanks > mjI am rusty on this but I think you need a power of 4 and then a phase- locked loop. You then divide down by 4 the recovered frequency. Will be a bit noisy.
Reply by ●September 4, 20082008-09-04
>On Sep 4, 1:10 am, "m" <stuttbr...@hotmail.com> wrote: >> Hi everybody, >> >> I am implementing a GMSK demodulator. To achieve coherent demodulation,I>> recovered the frequency with the power of 4 of the signal. How can I >> recover then the phase? Can anybody give me any clue? >> >> Thanks >> mj > >I am rusty on this but I think you need a power of 4 and then a phase- >locked loop. You then divide down by 4 the recovered frequency. Will >be a bit noisy. >Thank you for your answer, I tried what you suggest but the peak that should happen at 4 times the frequency is very weak and, as there is doppler, maybe the PLL could lock to a wrong frequency. Any other ideas? Thansk a lot mj