INDOOR LOCATION BASED ON IEEE 802.11 ROUND-TRIP TIME MEASUREMENTS WITH TWO-STEP NLOS MITIGATION

Abstract

This paper presents a comprehensive location scheme in a rich multipath environment. It is based on the estimation of the distance between two wireless nodes in line-of-sight (LOS) from the best statistical estimator of the round-trip time (RTT), assuming a linear regression as the model that best relates this statistical estimator to the actual distance. As LOS cannot be guaranteed in an indoor environment, the efiect of non-line-of-sight (NLOS) is mitigated by a two-step correction scheme. At a flrst step, the severe NLOS error is corrected from distance estimates applying the prior NLOS