Continuous space estimation for WLAN location determination systems

WLAN location determination systems add to the value of a wireless network by providing the user location without using any extra hardware. Current systems return the estimated user location from a set of discrete locations in the area of interest, which limits the accuracy of such systems to how far apart the selected points are. In this paper, we present two techniques to estimate the user location in the continuous physical space, namely the center of mass technique and time averaging technique. We test the performance of the two techniques in the context of the Horus WLAN location determination system under two different testbeds. Using the center of mass technique, the performance of the Horus system is enhanced by more than 13% for the first testbed and more than 6% for the second testbed. The time-averaging technique enhances the performance of the Horus system by more than 24% for the first testbed and more than 15% for the second testbed. The techniques are general and can be applied to any of the current WLAN location determination systems to enhance their accuracy. Moreover, the two techniques are independent and can be applied together to further enhance the accuracy of the current WLAN location determination systems

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