Composite fading in non-line-of-sight off-body communications channels

In this paper, we investigate the characteristics of the composite fading observed in non-line-of-sight (NLOS) off-body communications channels using the η-μ/inverse gamma distribution. We use a number of different datasets obtained from NLOS off-body measurements which have been performed in a range of different environments at 5.8 GHz and 60 GHz. In all cases, the bodyworn node was positioned on the front-central chest region of an adult male. It is shown that the η-μ/inverse gamma model provides an excellent fit to the measurement data for all of the considered cases. Using the Akaike information criterion (AIC), we have compared the η-μ/inverse gamma model with other composite and non-composite fading models associated with the NLOS channel conditions. The AIC results confirm that the η-μ/inverse gamma model was the most likely model to have been responsible for generating the channel data from the set of candidates which were considered.