LEGR: A Load-Balanced and Energy-Efficient Geographic Routing for Lossy Wireless Sensor Network

Geographic routing is attractive in wireless sensor networks due to its efficiency and scalability. Previously proposed geographic routing protocols commonly employ a maximum- distance greedy forwarding technique. However, recent experiments also have shown that wireless link can be extremely unreliable. Simple greedy forwarding will cause high packet drop rate in realistic link environment. Scarce sensor energy is dissipated, and the lifetime of the network is shortened. Therefore, improve the energy efficiency and load balance to prolong the network lifetime has become the important design considerations for sensor network geographic routing in lossy wireless link. In this paper, we propose LEGR protocol, which use energy aware metrics together with geographical information and packets reception rate to make routing decisions. A novel link estimator and real time energy estimation scheme is designed in the sub layer of the LEGR protocol to get the neighbour nodes' PRR value and current energy level. To evaluate the efficiency and the effectiveness of the proposed protocol, we define several performance metrics. In terms of theses metrics, our comprehensive simulation results show that, compared with PRR*distance forwarding scheme, LEGR extend the lifetime of the sensor network about 20% with approximate delivery rate and energy efficiency. Compared with GEAR and GPSR, LEGR performs better in terms of almost all the performance metrics.