Simple approach for passive RFID-based trilateration without offline training stage

Abstract

This work presents a modified trilateration method for use in passive radio-frequency identification (RFID) indoor localization systems. The modification allows to eliminate the preliminary stage of collecting measurement data from RFID tags without significant localization accuracy degradation (the experiments showed the increase of the mean error by only 0.4 cm). The approach is based on using a simple linear model for the function of distance vs. measurement data, taking into account the possible ellipticity of RFID tag position figures, and processing measurements of different types-namely, received signal strength (RSS) and read rate (RR).