RSS-based Location and Transmit Power Estimation of Multiple Co-Channel Targets

In this paper we consider the problem of multitarget localization using sensor networks, where the received signal strength of targets are measured at sensor nodes and are processed at a fusion node to estimate the location as well as the transmit power of all targets. As we do not consider any kind of division multiplexing, e.g., TDMA or FDMA, targets cause each other co-channel interference. This is a very hard problem, especially because the transmit power of targets can be different. The classical methods in which the power of a single target cancels out by dividing the received power at different sensors, do not apply to our problem, as the received power of each sensor is the superposition of more than one term, each of which corresponding to one target. We tackle the problem by a grid based approach, i.e., discretizing the area, and proposing an adaptive scheme to refine the position of grid points. The proposed algorithms are based on mixed integer optimization approach.