Analytical Investigation of Body-Centric Communication Links Based on Path Loss in Indoor Environment

Abstract

In this paper, a detailed analysis has been carried out related to body-to-body communication links in an indoor office environment using compact ultra-wideband wearable antennas. The links have been analysed on the basis of path loss magnitude variation and statistical information which are dependent on the orientation and distance. Four orientations of the transmitter and receiver are chosen, namely facing front, back, side right, and side left. The distance between the links is varied up to 5 m to consider the effect of separation between the Tx and Rx. The path loss magnitude has been classified into three ranges, which mainly represent direct path propagation (R1:40–55 dB), partially obstructed/high multipath links (R2:55–60 dB), and totally obstructed links (R3 > 60 dB). The presence of path loss in the range R1 is highest (35%) for the case when the Tx is facing front for B-to-B links due to the high chance of direct line-of-sight propagation between the Tx and Rx. The percentage of occurrence of PL (>60 dB) is highest (95 %) for the scenario in which the Tx is facing back for B-to-B links which is due to the obstruction caused for all the orientations of the receiver. The difference in PL statistics and modelling is observed for various B-to-B links that are attributed to the fact of the presence of two human subjects and the corresponding orientations. This leads to variation in the antenna radiation pattern which in turn affects the propagation characteristics and the channel parameters.