A Performance Study of a Fast-Rate WLAN Fingerprint Measurement Collection Method

Indoor positioning systems exploiting wireless local area network (WLAN) signal measurements, such as received signal strength (RSS), are gaining popularity due to high accuracy of the results. Sets of RSS and other measurements at designated locations from available WLAN access points are conventionally called fingerprints and typically retrieved from network cards at a 1-Hz rate. Such measurement collection is needed for the offline radio map surveying stage which assigns fingerprints to locations, and for online navigation stage when collected measurements are associated with the radio map for positioning. As WLAN networks are not originally designed for localization, the network cards occasionally miss the fingerprints, measurement fluctuations necessitate statistical signal processing, and the surveying process is very time consuming. This paper describes a fast measurement collection approach that addresses the mentioned problems-higher probability of measurement acquisition, more data for statistical processing, and faster surveying. The approach is further analyzed for practical setting applications.