Time-of-arrival estimation through WLAN physical layer systems
Time-of-arrival (ToA) has been the most popular measurement parameter when estimating distance between two nodes, i.e., ranging. Several localization-only systems such as radar systems, satellite positioning systems, ultra-wideband systems provide their accurate ToA estimation methodologies for the ranging in their physical layer. In contrast to the localization-only systems, wireless LAN (WLAN) has no standard rule for accurate ranging method. Delay and channel uncertainty is the major problem of the ToA estimation. In this paper, delay characteristic of WLAN system is analyzed and how accurate ranging is possible using ToA estimation through WLAN physical layer round-trip time measurement. Experimental results of indoor/outdoor ranging and positioning are also provided.
wlan toa localization los/nlos identification experiment