Improved Antenna Mounting Method for UWB BAN Channel Measurements

In this paper, a mounting method is proposed for antennas used in ultra wideband (UWB) body area network (BAN) channel sounding, which reduces the antenna’s electromagnetic coupling to the human body. Coupling with the body is shown to distort the free space characteristics of the antenna. An antenna mount modification is proposed to reduce this distortion, and decrease the variation in antenna characteristics when mounted. The antennas reflection coefficient from 4 to 9 GHz is used to assess the coupling of two UWB BAN antennas when they are mounted at different distances from the skin and at several locations on the body. The free space characteristics of the modified antennas are also tested, showing a reduction of up to 4.7 dB of radiated power into the body. The modified antennas are tested in BAN measurement campaigns showing the fading depth and coherency time of the channels.