Opportunistic Indoor Localization and Navigation Using Wireless LAN (802.11a/g) Signals

Huilin Xu and Liuqing Yang

Abstract:	The Global Positioning System (GPS) has been the main method for wireless localization and navigation. However, its application is constrained when the GPS signals is unavailable in indoor, metropolitan and heavyfoliage scenarios. Therefore, we need to exploit the terrestrial wireless signal for positioning and navigation. In this paper, we apply the wireless local area network (WLAN) IEEE 802.11a/g signals for time-difference-ofarrival (TDoA) based ranging and localization. We propose a simple model-based time-of-arrival (ToA) estimation approach. In this approach, the channel impulse response (CIR) is recovered with a simple equally-spaced model. Then, the delay of channel path is estimated by minimizing the energy leakage from the first path. Compared with the widely adopted space alternating generalized expectation maximization (SAGE) algorithm, the model-based approach has the advantage of lower complexity. Simulation results show that the model-based approach can achieve similar performance as the SAGE algorithm. Based on this ToA estimator, we realize the TDoA-based and TDoA-Doppler hybrid localization algorithms. Simulations are also carried out to corroborate our theoretical analysis.
Published in:	Proceedings of the 20th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2007) September 25 - 28, 2007 Fort Worth Convention Center Fort Worth, TX
Pages:	1839 - 1844
Cite this article:	Xu, Huilin, Yang, Liuqing, "Opportunistic Indoor Localization and Navigation Using Wireless LAN (802.11a/g) Signals," Proceedings of the 20th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2007), Fort Worth, TX, September 2007, pp. 1839-1844.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In