Influence of the human activity on the propagation characteristics of 60 GHz indoor channels

The 60 GHz frequency band appears to be very promising for wireless multimedia services in the next years. The 60 GHz propagation channel has to be accurately characterized for an appropriate design of high data rate systems (>100Mb/s). In this paper, our interest is to be determine the influence of the human activity on the propagation characteristics at 60 GHz. This influence is hardly ever taking into account in the published studies on the 60 GHz channel characterization. However, the human activity is a determining factor at millimeter-waves. Channel sounding campaigns have been conducted. The measurement results highlight the strong disruptions caused by a person shadowing the direct path between two antennas. These disruptions make the channel unavailable for durations greater than 100 ms. Long-term measurements are analyzed in order to evaluate the "unavailability rate" of 60 GHz radio links. From these results, some solutions are suggested in order to reduce the shadowing problems.