TDoA localization for wireless networks with imperfect clock synchronization

With the advent of an ubiquitous computing environment, the need to capture location information and incorporate it into applications has become urgent. In particular, time difference-of-arrival (TDoA) localization is considered to be a cost effective and accurate localization technique. However, the local clocks of the access points (APs) are required to be fully synchronized with each other. If clock offsets exist, TDoA localization can yield a poor localization performance. In this paper, we propose a TDoA-based localization technique that simultaneously estimates the client location and clock offsets of the APs. The simulation and experimental results show that the proposed localization algorithm alleviates the impact of imperfect clock synchronization among APs, thereby improving the localization accuracy.

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