RSSI-based maximum likelihood localization of passive RFID tags using a mobile cart

Summarization: In this paper a maximum likelihood estimator of the locations of passive RFID tags is presented, exploiting the Received Signal Strength Information (RSSI) collected at the reader. The reader-antenna is fixed on a moving cart and collects RFID data in the area of interest. Locations of the reader-antenna and of the target-objects are obtained by the RSSI of reference tags placed at known positions. The proposed method can be applied using commercial RFID equipment. Measurements were conducted in an office environment; mean error of 25cm with standard deviation equal to 12,4cm is recorded. Localization accuracy can be further improved by increasing the density of the reference tags and the number of reader antennas. Presented on