Suboptimal noncoherent detection of CPFSK

The article addresses the detection of binary, random phased CPFSK signals in the presence of white Gaussian noise. The proposed noncoherent suboptimal receiver is comprised of a pair of linear filters, an envelope detector and a decision unit. This receiver is practically attractive as it simplifies considerably the complexity when compared to the symbolwise optimal noncoherent receiver. First it is determined that the optimal filters are in the space spanned by the transmitted signals. This result is incorporated to find the best noncoherent suboptimal receiver in extreme cases, i.e., for high and low SNR values, which is equivalent to the determination of the filter coefficients that minimize the associated error probability. The asymptotic analytical evaluation of performance, displayed in the article, facilitates one to find efficient yet relatively simple receivers