We address channel characterization and modeling for medical wireless body-area networks (WBANs) based on the optical wireless technology. We focus on the intra-WBAN communication links, i.e., between a set of medical sensors and a coordination node, placed on the patient's body. We consider a realistic mobility model, e.g., inside a hospital room, which takes into account the effect of shadowing due to body parts movements and the variations of the underlying channels. To take into account the global and local user mobility, we consider a dynamic model based on a three-dimensional animation of a walk cycle, as well as walk trajectories based on an improved random way-point mobility model. Then, Monte Carlo ray-tracing simulations are performed to obtain the channel impulse responses for different link configurations at different instants of the walk scenarios. We then derive first-and second-order statistics of the channel parameters such as the channel DC gain, delay spread, and coherence time, and furthermore, propose best fit statistical models to describe the distribution of these parameters for a general scenario.

The increasing percentage of aging population and chronic diseases on one hand, and the advances in the development of integrated short range wireless technologies on the other hand, have created a growing interest in the development of medical telemonitoring and telecare systems through the use of medical on-body sensor networks, also known as medical wireless body area networks (WBANs). This paper provides an overview of the main wireless technologies that can be used for WBANs in the medical domain and discusses the major requirements in such applications. While radio frequency technologies are well established solutions for interconnecting WBANs, the high risk of interference in such networks motivates the use of alternative or complementary technologies including optical wireless communications.Index Terms-Wireless sensor networks; body area networks; medical on-body networks; optical wireless communications.