120 Int. J. Sensor Networks, Vol. 14, No. 2, 2013 Copyright © 2013 Inderscience Enterprises Ltd. Energy-aware utility optimisation for joint multi-path routing and MAC layer retransmission control in TDMA-based wireless sensor networks Meng Zheng, Wei Liang* and Haibin Yu Lab of Industrial Control Network and System, Shenyang Institute of Automation, Chinese Academy of Sciences, 114 Nanta Street, Shenhe District, Shenyang, Liaoning Province, 110016, China Email: zhengmeng_6@sia.cn Email: weiliang@sia.cn Email: yhb@sia.cn *Corresponding author Yang Xiao Department of Computer Science, The University of Alabama, 101 Houser Hall, Box 870290, Tuscaloosa, AL 35487-0290, USA Email: yangxiao@ieee.org Jianda Han State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, 114 Nanta Street, Shenhe District, Shenyang, Liaoning Province, 110016, China Email: jdhan@sia.cn Abstract: 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 energy- efficient 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. Keywords: wireless sensor networks; multi-path routing; retransmission control; convex optimisation. Reference to this paper should be made as follows: Zheng, M., Liang, W., Yu, H., Xiao, Y. and Han, J. (2013) ‘Energy-aware utility optimisation for joint multi-path routing and MAC layer retransmission control in TDMA-based wireless sensor networks’, Int. J. Sensor Networks, Vol. 14, No. 2, pp.120–129. Biographical notes: Meng Zheng holds a PhD degree in Mechatronic Engineering from Shenyang Institute of Automation, Chinese Academy of Sciences. He is currently an Assistant Professor at the Lab of Industrial Control Network and System, Shenyang Institute of Automation, Chinese Academy of Sciences. His research interests are wireless ad hoc & sensor networks.