Frequency tracking by MAP demodulation and by linear prediction techniques

Maximum posterior probability (MAP) demodulation with delay of an FM signal in the presence of noise is realized and compared with a) Griffiths´ linear prediction method, b) a complex-valued version of Griffiths´ method, c) three new modifications of Griffiths´ method which can improve the performance of this method, and d) maximum-likelihood (ML) frequency estimation. These first quantitative results on MAP demodulation with delay show an advantage of a few db in output SNR at high input CNR and much larger advantages at low input CNR, relative to the other techniques.