Modeling the effect of human body on TOA ranging for indoor human tracking with wrist mounted sensor

In TOA based indoor human tracking system, target sensors are often mounted to the surface of human body which may raise non-line-of-sight (NLOS) issues and give raise to significant ranging error. However, analysis on the influence of human body on TOA ranging result has never been seen from previous researches. In this paper, we focus on geometrical information, effect of system bandwidth and signal to noise ratio and provide a detailed analysis on the effect of human body on TOA ranging. Perspective of creeping wave around the surface of human body has been taken into consideration and a statistical TOA ranging error model has been built based on measurements in office environment. The wrist model in this paper separates the ranging error caused by multi path phenomenon and ranging error caused by blockage of human body by partitioning the measurement scenario into line-of-sight (LOS) and NLOS scenario. Comparison has been made between wrist model and chest model in our previous work and the performance of this wrist model has been validated.