Sensor Localization Using Radio and Acoustic Transmissions from a Mobile Access Point

Abstract : We consider the problem of sensor node localization in a randomly deployed sensor network, using a mobile access point (AP). The mobile AP can be used to localize many sensors simultaneously in a broadcast mode, without a preestablished sensor network. We consider a multi-modal approach, combining radio and acoustics. The radio broadcasts timing, location information, and acoustic signal parameters. The acoustic emission may be used at the sensor to measure Doppler stretch, time delay, received signal strength, or angle of arrival. We focus on the case of narrowband Doppler shift in this paper, and we present a maximum likelihood estimator for sensor localization and show that its performance achieves the Cramer-Rao bound.