Complete Coverage of Mobile Targets in Backscatter-Aided IoT Networks

This article considers the problem of monitoring one or more mobile targets over a given planning horizon. Unlike previous works, it leverages ambient backscatter communication to reduce the energy expenditure of sensor nodes in order to prolong coverage lifetime. We outline a mixed integer linear program (MILP) that aims to maximize the number of time slots in which all mobile targets are monitored by a sensor node; a.k.a. complete mobile targets coverage. For a given targets trajectory, it outputs the activation time of sensor nodes to ensure all targets are monitored by at least one sensor node. Further, we propose an algorithm called maximum energy opportunity selection (MEOS), which uses the energy level of sensor nodes to set their operation mode. The simulation results show that the complete mobile targets coverage lifetime of MILP and MEOS algorithms improves when nodes employ backscatter communications. Specifically, it leads to a 79% improvement in complete mobile targets coverage lifetime.