Power Allocation for Target Positioning in Asynchronous Wireless Radar Sensor Networks

Target detection and positioning in harsh environments plays a main role in wireless radar sensor networks (WRSNs). Due to the difficulties in high accuracy clock synchronization among multiple sensor nodes, a novel asynchronous measurement model based on a combination of round trip measurements (RTM) and time difference of arrival (TDOA) is presented in this paper. We then investigate the fundamental accuracy limits of target localization based on the RTM-TDOA model. In order to achieve the tradeoff between the target localization accuracy and energy consumption, an optimal power allocation framework among the sensor nodes is thus presented. Furthermore, a corresponding robust power allocation strategy is also given to deal with the position uncertainty of the target. Both power allocation problems are proved to be convex and can be solved efficiently. We validate the analysis, and evaluate the performance of the proposed strategies through numerical results. Meaningful performance benchmarks can also be achieved by the presented frameworks in this paper.