Performance Evaluation of Wireless Body Sensors in the Presence of Slow and Fast Fading Effects

A theoretical method for analyzing the performance of wireless body sensors in terms of channel capacity and bit-error-rate (BER) in the presence of slow and fast fading effects is presented. Analytical closed-form expressions for the channel capacity and BER for implant-to-implant, implant-to-body-surface, and body-surface-to-body-surface propagation scenarios are developed. Numerical results of the channel capacities and the BERs are presented utilizing realistic channel models for wireless body area networks (WBANs). The results indicated high system outage probability and degraded channel capacity caused by the complex propagation mechanisms of radio frequency signals on the surface and inside the human body. The communication links of WBANs should thus be optimized using fade mitigation techniques suitable for miniature wireless electronic devices to achieve the targeted high quality-of-service requirements of biomedical systems. In general, the results give an insight into the effect of the propagation channel on system performance, and may allow service providers to evaluate the technical feasibility of biomedical systems for various propagation scenarios.