Re: [Discuss-gnuradio] CPM timing recovery

[Robert McGwier]

Since the signal will not really have infinite bandwidth (instantaneous 
transitions from one state to the next),  the envelope will not be of 
constant modulus.  The signal will be amplitude modulated with a 
component due to the data transitions.  Looking at the modulus or 
modulus squared will reveal a line in the fft due to this amplitude 
modulation.

Bob



David Scaperoth wrote:
> hey all,
>  
> I am trying to demodulate a CPM (for now I'm doing it with 4-CPFSK 
> signal with Raised Cosine pusle shaping) signal without knowing the 
> symbol rate (i.e. the samples per symbol).  does anyone know if this is 
> possible?  Papers that I have read on timing recovery for CPM assume 
> that the symbol period is known. 
>  
> thanks,
>  
> David
>
>
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