A simple and accurate analysis of digital communication systems with diversity reception in different fading environments

Abstract

This paper surveys some of the diversity techniques commonly used in cellular radio and satellite communication systems to mitigate the detrimental effects of signal fading. Subsequently, an analytical technique well suited to numerical analysis is presented for computing the average symbol error probability (SER) of a wide class of coherent, differentially coherent and noncoherent communication systems with microdiversity reception under a myriad of fading scenarios. We restrict our analysis to a predetection maximal-ratio combining (MRC) scheme, although this method applies to other diversity combining techniques as well. Our novel derivation relies upon the properties of the moment generating function (MGF) of the fading channels, the use of an alternative exponential form of the complementary error function, and the application of Gauss-Chebychev quadrature (GCQ) rules. The closed-form expressions obtained are sufficiently general to allow for arbitrary fading parameters as well as dissimilar mean signal strengths across the diversity branches. Moreover, this method is computationally stable and approximates the true value of average SER within any degree of accuracy.