Investigation of short-range, broadband, on-body electromagnetic wave propagations

Electromagnetic wave propagation over a broad frequency band (300 MHz – 3 GHz) and within short ranges (<40 cm) was investigated for on-body wireless channel communications. Experimental and modelling methods were used to examine two scenarios: along the body surface [line-of-sight (LOS)] and around the body torso [non-LOS (NLOS)]. The LOS scenario was modelled simply as an infinitely-large ground plane, and the NLOS scenario as a finite-height cylinder. Homogeneous muscle tissue properties were assumed for both models. The propagation characteristics were extracted using signal-processing techniques. The results show that the space wave is the dominant wave for the LOS scenario and the creeping wave for the NLOS scenario over the short ranges of the body's surface. The analytical models based on the ground wave theories of Bannister and Wait were derived and shown to agree well with the experimental and simulation data.