On the shadowing distribution for ultra wideband in-body communication path loss modeling

Current path loss models for ultra wideband in-body communication are usually based on finite-difference time-domain simulations. Due to the computational complexity they include only a limited number of transmitter-receiver pairs. We propose a new channel modeling approach based on a plane wave propagating through a multi-layered dielectric. With this approach it is possible to calculate the path loss of many more transmitter-receiver pairs. Hence, the statistical distribution of the path loss can be evaluated better. Our results show that the standard deviation of the path loss increases in fact drastically with distance between transmitter and receiver. For distances of more than 100mm it gets much larger than the standard deviation proposed in literature. That means the variation in path loss might in reality be much higher than current models indicate.