Channel Models for On-Body Communications

The need to find reliable and simultaneously simplistic propagation models in the majority of frequency bands, where wireless body area networks (WBANs) operate in, is the driving force leading to the appearance of many studies on that topic during recent years. Transmission in WBANS is significantly affected by human body tissues and is frequency dependent. Signals are attenuated and delayed to a large extent and reach the receiver as a sum of several components traveling in multiple paths. Shadowing phenomena are likely to appear due to human body movements and the variations in the surroundings of human body parts. Propagation paths can also experience fading due to energy absorption, reflection, and diffraction mechanisms, as well as due to multipath effects of the surrounding environments. All the above phenomena have a different degree of influence on the WBAN behavior according to the frequency band of operation. This chapter briefly summarizes the fundamental channel models for on-body communications launched by either the IEEE or other independent research and standardization efforts. The basic experiment setups are described in detail, while the presented results can be considered as a valuable tool for researchers and designers working in that area, who desire to build their own applications based on WBANs. © 2015 Elsevier Inc. All rights reserved