Statistics and system performance metrics for the Two Wave with Diffuse Power fading model

The Two Wave with Diffuse Power (TWDP) fading model was proposed by Durgin, Rappaport and de Wolf as a generalization of the Rayleigh and Rician fading models. This model can characterize a large range of fading behavior and has a geometric justification in terms of two dominant line of sight components in the presence of a diffuse component. The fact that the pdf of the TWDP model is not in closed-form has hindered the analytical characterization of this otherwise intuitive model. We show that any metric which is a linear function of the envelope statistics of the TWDP fading model can be computed as a finite integral of the corresponding metric for the Rice model. Employing this approach, we obtain simple expressions for some performance metrics for this fading model hitherto not found in the literature, such as the Amount of Fading, the Level Crossing Rate and the Moment Generating Function, by leveraging existing results for Rician fading.