Performance of Pre-and Post Equalization for FSK Signals in Multipath Environments

This paper characterizes the performance of adaptive filters positioned after the FM-discriminator for minimum-shift keyed (MSK) signals received in multipath environments. Previous work presented a new receiver architecture based on equalizing the signal after the FM discriminator, rather than before it. Simulation results using measurements recorded from actual multipath channels showed superior performance for some channels when compared to a more traditional CMA pre-discriminator equalizer. A recent theoretical analysis of the post-discriminator filter was limited to channels with very mild multipath. This paper uses simulation studies to systematically investigate the performance of pre- and post-detection filters as a function of filter parameters for a multipath channel with a single reflection.