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Accuracy Performance Analysis between War Driving and War Walking in Metropolitan Wi-Fi Localization
November 2010 (vol. 9 no. 11)
pp. 1551-1562
Arvin Wen Tsui, National Taiwan University
Wei-Cheng Lin, National Taiwan University
Wei-Ju Chen, National Taiwan University
Polly Huang, National Taiwan University
Hao-Hua Chu, National Taiwan University
Wi-Fi ingerprint-based localization is currently the most promising approach to building metropolitan-scale localization systems for both indoor and outdoor environments. A Wi-Fi fingerprint localization system makes use of a radio map that contains Wi-Fi signals received at various locations, and uses the map for location estimation. Thus, the accuracy of a Wi-Fi fingerprint localization system greatly depends on the quality of its radio map. This paper explores various properties of a metropolitan radio map that may affect the accuracy of Wi-Fi fingerprint localization systems. In this study, metropolitan-scale radio maps are obtained using war walking and war driving. These maps contain hundreds of thousands of access points and signal samples. A detailed comparison analysis of selected radio map properties reveals how different map properties affect the difference between the positional accuracies of the driving and walking radio maps in Wi-Fi fingerprint-based localization.

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Index Terms:
Metropolitan-scale Wi-Fi localization, radio maps, war driving.
Arvin Wen Tsui, Wei-Cheng Lin, Wei-Ju Chen, Polly Huang, Hao-Hua Chu, "Accuracy Performance Analysis between War Driving and War Walking in Metropolitan Wi-Fi Localization," IEEE Transactions on Mobile Computing, vol. 9, no. 11, pp. 1551-1562, Nov. 2010, doi:10.1109/TMC.2010.121
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