Modeling indoor TOA ranging error for body mounted sensors

In Time of arrival (TOA) based indoor human tracking system, the human body mounted with the target sensor can cause non-line of sight (NLOS) scenario and result in significant ranging error. However, the previous studies on the behavior of indoor TOA ranging did not take the effects of human body into account. In this paper, we introduce a statistical TOA ranging error model for body mounted sensors based on the measurements in a typical office building. This model separates the ranging error into multipath error cased multipath combination and undetectable direct path (UDP) error derives from the body-caused NLOS. Both multipath error and UDP error are modeled as a Gaussian variable. The distribution of multipath error is relative to the bandwidth of the system and the distribution of UDP error is relative to the angle between the face direction and the direction of TX-RX, SNR and bandwidth of the system, clearly shows the effects of human body on TOA ranging.