Reliable indoor location sensing technique using active RFID

This paper aims to locate multiple tags in the indoor environment by using low cost devices, active Radio Frequency Identification (RFID). A more reliable positioning algorithm using Mahalanobis distance based on Received Signal Strength Indication (RSSI) is proposed to improve location accuracy, since in this method covariance is taken into account to avoid unnecessary mistakes. Reference tags and readers with known location, which is proposed in LANDMARC system, are used to estimate target tag location. The results from conducting extensive simulations demonstrate that the proposed algorithm can achieve more reliable and higher performance than LANDMARC algorithm without using any additional optimal methods.