WidthSense: Wi-Fi Discovery via Distance-Based Correlation Analysis

Abstract

In this letter, we present a lightweight yet accurate scheme for mobile devices, called WidthSense, that identifies available Wi-Fi systems by using a collocated heterogeneous wireless personal area network (WPAN) radio such as Bluetooth or ZigBee. Motivated by the observation that Wi-Fi signals in a 2.4 GHz ISM band can be sensed by a WPAN radio over the frequency range of the corresponding Wi-Fi channel, WidthSense exploits the temporally correlated fluctuations in multiple narrowband WPAN-channels. To this end, we employ a distance-based similarity as a measurement of dependence between WPAN channels. We implement a prototype of WidthSense using a Bluetooth-compliant wireless transceiver, and demonstrate its efficiency. Experimental results show that WidthSense achieves high detection accuracy with a short delay (-500 ms).