Configurable hardware-based radio interferometric node localization

Wireless ad-hoc sensor networks are typically deployed randomly in space to gather information about the physical world. In these spatially random sensor networks, one of the fundamental problems is precise node localization along with the key requirement to keep node cost at minimum. Existing radio interferometry-based node localization techniques achieve cm resolution using only low-cost radio chips readily available on sensor nodes. This paper proposes an alternative hardware-based solution for the signal processing part of such a technique. We show that our approach tolerates a much wider range of interference frequencies while freeing up precious computational and storage resources on the sensor node. The proposed ranging functionality can eventually be included in current COTS radio transceiver chips, thus accurate localization will be available on the nodes, without a significant additional cost in computation or price.