Energy-efficient joint routing and power allocation optimisation in bit error rate constrained multihop wireless networks

Energy efficiency is a crucial design issue in energy-constrained wireless networks to ensure uninterrupted information exchange. With the requirement of average end-to-end bit error rate (BER), the problem of joint routing and power allocation optimisation in multihop wireless network is studied here for two network power management policies: one is to minimise overall transmit power and the other is to maximise network lifetime. The proposed minimum total power strategy is optimal for minimising the overall transmit power consumption in the network and is preferable in network with tethered energy resources. To maximise the lifetime of a network with battery-operated nodes, the authors have developed two residual energy-aware joint routing and power allocation strategies: path lifetime maximisation (PLM) strategy and minimum weighted total power (MWTP) strategy. A distributed implementation for these strategies is also presented. Simulation results demonstrate that the proposed strategies achieve significant power saving and prolong network lifetime considerably over traditional routing algorithm with individual link BER constraint. It has also been shown that at reasonably low route refresh interval, the MWTP strategy performs best in terms of network lifetime, whereas at very high route refresh interval, the PLM strategy is optimal for network lifetime maximisation.