Outage probability for maximal ratio combining receivers in asynchronous CDMA channels

Abstract

Direct sequence code division multiple access (DS-CDMA) receivers typically use maximal ratio combining (MRC) to favorably combine the energies of distinct multipath components from diversity branches. There have been a large number of studies on DS-CDMA and MRC receivers, respectively, but there have been a comparatively small number of papers analyzing MRC for DS-CDMA. Prior work does not accurately analyze the outage probability using the actual random characteristics of the cross correlations, instead, equality has been assumed. The contribution of this paper is to provide a general and accurate analysis of the outage probability of the diversity receiver in CDMA systems without compromising approximations. From the analytical and numerical results, it is shown that the analysis provides an accurate closed-form solution.