Measurement of Local Enviromental Effects in UWB Channels

Abstract

The effects of local objects and in particular, human body shadowing in and around radio link on the UWB channels have been studied. In outdoor environments, human body blockage causes deep fades, and is perceptible. In indoor environments, since there are objects nearby the radio link, radio waves diffracting around the body and reflecting from nearby objects would contribute to the received signal, and fades margin is relatively smaller than the outdoor case. When the radio link is blocked by human body, the duration and depth of fades are correlated with the blocking rate of the person, and at full blockage fades of 10-15 dB or even more are observed at different frequencies. When the link is obstructed by a wall (or other objects) in addition to human body, fades due to human body blockage becomes imperceptible at some frequencies.