Efficient Approximation to Rician and Hoyt Product Distributions With Applications to Wireless Communication Channels
Emílio C. G. Wille · IEEE Wireless Communications Letters · 2025
In wireless communications, fading refers to fluctuations in the strength of the received signal. In recent years, the cascaded fading approach has gained increased attention. This method expresses the signal strength as the product of multiple random components. This letter presents closed-form approximations for the probability density function (pdf) and the cumulative distribution function (cdf) of the product of independent and identically distributed Rician and Hoyt random variables. The inspiration for this approach came from the importance of these statistical models in describing several realistic wireless transmission scenarios. Unlike previous works, the approximation relies on a generalized gamma pdf and does not require nested infinite series or numerical integration. As an application, closed-form expressions for the outage probability (OP) and average symbol and bit error rates (AERs) for M-QAM digital modulations over cascaded fading channels are derived. The accuracy of the numerical results is extensively validated through Monte-Carlo simulation.