The effects of human body shadowing in RF-based indoor localization

Abstract

In radio frequency based indoor human localization systems with body mounted sensors, the human body can cause non-line-of-sight (NLOS) effects which might result in severe range estimation and localization errors. However, previous studies on the impact of the human body only conducted static experiments in controlled environments. We confirm known effects and conduct real-world experiments in a typical indoor human tracking scenario using 2.4 GHz time of flight (TOF) range measurements. We analyze the effect on the raw measurements and on the localization results using the localization algorithms Centroid, NLLS, MD-Min-Max, and Geo-n. The experiment design is focused on incident management, where an infrastructure might only be installed in front of the building. We show that these effects have considerable impact on the localization accuracy of the person.