Depolarisation Model for a BAN Indoor Scenario

In this paper, an analysis of depolarisation in Body Area Networks for Body-to-Infrastructure communications based on a measurement campaign in the 5.8 GHz band in an indoor environment is performed. Measurements were made with an off-body antenna transmitting linearly polarised signals and dual-polarised receiving antennas carried by the user on the body. A Normal Distribution with a mean of 2.0 dB and a standard deviation of 4.3 dB is found to be the best fit for modelling cross-polarisation discrimination. The average correlation between the signals received by the orthogonally polarised antennas is below 0.5, showing that polarisation diversity can be used. A model is proposed for the average value of the standard deviation of the cross-polarisation discrimination ratio as a function of the transmitted polarisation, the mobility of users and link dynamics.