The Fisher–Snedecor $\mathcal {F}$ Distribution: A Simple and Accurate Composite Fading Model

Abstract

We consider the use of the Fisher-Snedecor F distribution, which is defined as the ratio of two chi-squared variates, to model composite fading channels. In this context, the root-mean-square power of a Nakagami-m signal is assumed to be subject to variations induced by an inverse Nakagamim random variable. Comparisons with physical channel data demonstrate that the proposed composite fading model provides as good, and in most cases better, fit to the data compared to the generalized-K composite fading model. Motivated by this result, simple novel expressions are derived for the key statistical metrics and performance measures of interest.