Some new results on the asymptotic analysis for diversity receivers

This article derives a new class of closed-form asymptotic expressions for computing the average symbol error rate (ASER) and outage probability/capacity performance measures of digital communications with diversity transceivers. Specifically, we study the efficacy of our recently proposed normalized asymptotic probability density function (PDF) of signal-to-noise ratio (SNR) method to both unify and simplify the analyses of selection diversity combining (SDC), maximal ratio combining (MRC) and equal gain combining (EGC) diversity techniques in different multipath fading environments and modulation schemes. Our approach requires only the knowledge of the first non-zero term of Poincare/Taylor series expansion of the PDF of diversity combiner output SNR (thereby circumventing the difficulties involved in computing coefficients of higher order approximations) while yielding significantly better predictions than the traditional high-SNR approximation, especially in the low and medium mean SNR regions.