Joint node selection, flow routing, and cell coverage optimisation for network sum-rate maximisation in wireless sensor networks

In this study, the problems of joint node selection, flow routing, and cell coverage optimisation in energy-constrained wireless sensor networks (WSNs) are considered. Due to the energy constraints on network nodes, maximising network sum-rate under target network lifetime, flow routing, cell coverage, and minimum rate constraints is of paramount importance in WSNs. To this end, a mixed-integer non-linear programming problem is formulated, where the aim is to optimally select which network nodes to act as sensors or relays while ensuring connectivity to the fusion centre optimised network flows, and full network coverage. The formulated problem happens to be NP-hard (i.e. computationally prohibitive). In turn, a solution procedure based on the branch and bound with the reformulation-linearisation technique (BB-RLT) is devised to provide a (1 − ϵ)-optimal solution to the formulated problem. Simulation results are presented to validate the efficacy of the devised BB-RLT solution procedure. This work provides significant theoretical results on network sum-rate maximisation for WSNs under a variety of practical constraints.