On the scalability of a novel WLAN positioning system based on time of arrival measurements

TOA-based methods represent an interesting alternative to overcome important constraints of the existing fingerprinting solutions to locate WiFi devices indoors, especially in terms of accuracy, stability and quick deployment. However, in some situations the scalability of TOA-based methods to large number of users is expected to be degraded because of the traffic generated by the positioning process. This paper describes the architecture of a novel TOA-based WiFi location system and as main contribution presents an assessment of the system's scalability considering different location-based services and scenarios. Achieved results show that system is viable even in scenarios with a high density of terminals and allows reconsidering some system design issues in order to improve the quality of the positioning service.

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