UWB ranging with antenna proximity to the human head

Time-of-arrival (ToA) estimation used with ultra-wideband (UWB) technology has become the most popular technique for accurate indoor localization. Much work has been done on UWB ToA estimation in general. However, the effect of the radiation patterns of antennas used in localization applications have not been considered. This paper investigates the effect of user terminal (UT) antenna pattern on the detection of the direct path. The paper aims at presenting the ranging error in a practical scenario considering the fact that antenna pattern of UT are distorted by human body and the user orientation is random. The results are obtained in a typical industrial indoor environment for line-of-sight (LoS) scenario and are based on the ToA-based ranging technique. Moreover, this paper introduces a technique to synthesize the desired antenna patterns for the purpose of this study by employing spherical wave expansion (SWE) tool.