MULTIPLE ACCESS INTERFERENCE REDUCTION FOR DS-CDMA IN THE PRESENCE OF RAYLEIGH FADING

Abstract

This paper proposes an alternative transmission structure to the existing direct-sequence code division multiple access (DSCDMA) technique in order to alleviate the decision variable from a substantial portion of the multiple access interference (MAI) incurred over an asynchronous slow varying Rayleigh fading channel. The proposed technique uses a dual frequency switching system that shifts lagging interference components to an alternative frequency band thus reducing the degree ofMAI incurred in the considered symbol-by-symbol matched _lter recovery. Bit-error rate (BER) performance comparisons are offered for the use of both Gold andWalsh-Hadamard (WH) codes. The proposed technique successfully reduces the amount of MAI experienced, however, this reduction comes at the cost of an increased bandwidth.