A digital-phase window processing technique for fast acquisition of phase-shift keyed signals

This paper deals with the problem of fast carrier synchronization for phase shift keyed TDMA communication systems. A new variable sample digital phase window processing technique and maximum likelihood detection are presented as means to improve acquisition time. The new method reduces the average probability of error of single bit acquisition at a SNR of 14 dB better than 50% compared to the original adaptive phase tracking (APT) technique. Combined with maximal likelihood phase detection, the number of preamble bits may be reduced by two-thirds for an error rate of less than 10/sup -3/ and SNR of 14 dB. The statistics and theoretical limits of the acquisition probabilities and SNR degradation are calculated for various sample rates and preamble lengths in an additive white Gaussian noise (AWGN) channel. The analysis shows the substantial robustness of this means to acquire the carrier phase within fewer preamble bits, and provides an analytical means to evaluate various digital phase synchronization methods.