A Tractable Fading Channel Model With Two-Sided Bimodality

This paper presents the alternate Rician shadowed (ARS) fading model, a new statistical channel model that consists of two fluctuating specular components of which only one is active at a time. When a diffuse component is added, it can be regarded as a mixture of two Rician shadowed fading models. The ARS model has the advantage of providing either left-sided or right-sided bimodality (i.e., two-sided bimodality), depending on its shape parameters. This characteristic is not found in classical fading models, or even in more recent ones such as the two wave with diffuse power (TWDP) and the fluctuating two ray (FTR) models. This makes it suitable for fitting the bimodal fading distributions measured in systems, such as body-centric wireless links or land mobile satellite. To yield a mathematically tractable model, this research derives exact closed-form expressions for the following chief probability functions: 1) probability density function (PDF); 2) cumulative density function (CDF); and 3) moment generating function (MGF). The results obtained are used to analyze the performance of wireless communication systems subject to the ARS fading in terms of outage probability, ergodic capacity, and bit error rate. In addition, we show that the model provides a better fit for experimental measurements in body-centric scenarios than those reported in the literature.