Energy-aware utility optimisation for joint multi-path routing and MAC layer retransmission control in TDMA-based wireless sensor networks

This paper formulates a novel energy-aware utility optimisation (EUO) problem for joint multi-path routing and medium access control (MAC) layer retransmission control in time division multiple access (TDMA)-based wireless sensor networks (WSNs). As the EUO problem is non-convex and inseparable, we propose a heuristic method called Successive Alternating Convex Approximation (SACA) to approximately solve the problem. More precisely, we decompose the EUO problem into two alternating convex sub-problems, namely energy-aware multi-path routing and retransmission control. On one hand, given the time slot allocation, the multi-path routing balances the energy consumption within WSNs. On the other hand, provided the traffic distribution, retransmission control enhances the data reliability in the most energyefficient way. These two sub-problems are solved recursively by means of dual decomposition. The sequence of optimal solutions to these two sub-problems is shown to converge to some steady-state point that approximates a solution to the EUO problem.