A Study on Multipath Effect Mitigation using Trigger Signal in the 3D TDOA Positioning System

A study on the indoor positioning system has been active recently, and TDOA technique using acoustic signal has been used generally. The drawback of the TDOA is very weak against signal distortion due to multipath effect. Especially to estimate the smartphone position, the sound distortion is very severe, and the generated radio signal jitter when using WLAN or Bluetooth as a time reference signal makes the receiver difficult to estimate the position. In this paper, acoustic trigger signal for the receiver preparing the positioning signal reception is proposed, and the mitigation of the multipath effect is shown.