Comparison of correlator configurations for FSK demodulation

A new theoretical approach is presented to calculate the error performance of correlator receivers for noncoherent frequency shift keying (FSK) demodulation, which takes arbitrary IF bandlimiting into account and which does not involve any computations beyond a few numerical integrations and the calculation of a few FFTs. This approach is used to compare the performances of different types of correlator configurations. For an optimum choice of IF bandwidth (B=1/T) and deviation ratio (0.7), it is shown that the performance of all the types considered is almost identical to that of the ideal limiter-discriminator. For other choices of the deviation ratio and IF bandwidth, it is shown that some of the correlator configurations perform better than the ideal limiter-discriminator. This approach can also be used to predict the degradation of the probability of error due to nonoptimal sampling times