MGF-based Analysis of Maximum Ratio Combining Receiver over Fisher-Snedecor Composite Fading Channel

Fisher Snedecor composite fading model is the combination of Nakagami-m and inverse Nakagami-m distribution. The Nakagami-m is used to characterize the small scale fading, whereas shadowing is modeled by inverse Nakagami-m distribution. In this paper, the closed-form expression for moment generating function (MGF) of instantaneous signal to noise ratio (SNR) over independent identically distributed (i.i.d) Fisher-Snedecor composite fading channel using maximum ratio combining (MRC) diversity technique is derived. By using newly derived MGF expression, we derive the closed-form expressions of average bit error rate (ABER) or average symbol error rate (ASER) for different binary and multilevel modulation schemes. The expressions for average channel capacity (ACC) under two adaptive transmission protocols like optimum rate adaption (ORA) and channel inversion with fixed rate (CIFR) are also derived using proposed MGF. Further, the numerical results of newly derived expression are presented and compared with the results of Rayleigh and Nakagami-m distribution which is the special case of Fisher Snedecor composite fading model.