ADAPTIVE SEQUENCE RECEIVERS FOR MPSK OVER THE RAYLEIGH FADING CHANNEL

Abstract

Rayleigh fading is a problem which commonly occurs in mobile radio communication channels such as the satellite channel. Essentially, the fading produces a random amplitude gain and a random phase shift. In this thesis, a study is made of the performance of various methods to compensate for the effects of Rayleigh fading. It was assumed that the fading was slow and non-frequency-selective. The conventional method of dealing with the problem is to differentially encode the information (ie. to use DPSK). It will be shown that symbol-by-symbol receivers using Kalman filters and adaptive filter can improve the BER performance of DPSK by up to 3dB. Sequence estimation with a Viterbi-type algorithm can further improve the performance of Kalman filters and adaptive filter receivers. Besides simulating the various types of receivers, a theoretical analysis of the sequence estimation receiver was done to verify the results obtained by simulation.