A Timing False Lock Detector for M-ary Partial-Response CPM

We consider a timing false lock detector for continuous phase modulation (CPM), which is needed for M-ary partial-response CPM schemes. Our approach maintains a running count of successive, simple, short-term false lock decisions, rather than conducting a single, long-term decision. Using a Markov chain model, we show that our scheme can provide accurate and rapid synchronization for capacity-approaching CPMs that operate at very low signal-to-noise ratios.