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OPNET
Technologies OPNET is a
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Geographic and Energy-Aware Routing in Wireless Sensor Networks Energy efficiency is crucial for large scale sensor networks due to the intrinsic resource constraints of the wireless sensors and the infeasibility to change depleted batteries that may reside in hostile environments. This work proposes an energy efficient routing algorithm based on a two-layer wireless sensor network (WSN) architecture to maximize the lifetime. The proposed scheme takes advantage of the geographic deployment knowledge to build routing protocols. Linear programming formulations are developed to maximize the lifetime of WSNs. A hybrid energy-efficient routing scheme (HERS) is proposed to incorporate both max-min residual energy and min-max communication energy consumption information. Simulation results show that the proposed routing algorithms can prolong the lifetime of a WSN compared to the existing algorithms. In this work, we conduct a series of experiments with a relatively larger network size. We build the simulation environment by choosing a 50m*50m target area and vary the number of sensors in the network, excluding the cluster heads, from 40, 60, 80, to 100 respectively. Each group contains 10 non-cluster head sensor nodes and 3 cluster heads. Each sensor (including non-cluster heads or cluster heads) has an initial energy of 1 unit and generates packets of size 1000 bits per round. For the lower layer, each group has an optimal path whose information source is a non-cluster-head sensor node, and destination a cluster head. For the other nodes and cluster heads within this group, they all act as information relay units and just forward the whole packets they receive to the next hop. If the next hop is a cluster head which acts as the destination, it will process these packets and extract key information and then forward them to the base station via other cluster heads. This is the top layer's communication scheme, see next paragraph. Here we assume the extraction ratio is 1:10, which means in each round, a cluster head receives 1000 bits from the source node, and the key information 100 bits are extracted and forwarded to the next hop. In this series experiments, we adopt D-HERS scheme since D-HERS has a better performance than S-HERS in large scale networks. The results show that D-HERS has a stable lifetime level about 7200, which is about 1.1-2.0 times longer than that of CMLDA, and about 2.50 times longer than that of LRS. Publication using OPNET [1] Dengfeng Yang, Xueping Li, Rapinder Sawhney and Xiaorui Wang, "Geographic and Energy-Aware Routing in Wireless Sensor Networks", International Journal of Ad Hoc nd Ubiquitous Computing, 2007. |
