Research on relay node placement algorithm based on its capacity limitation in WSN

Energy consumption problem is one of the key issues in Wireless Sensor Network (WSN). Usually sensor nodes are far from one or more sink nodes. In such a case, it calls for deploying some relay nodes as the interval nodes to transmit data from sensor nodes to sink nodes. A relay node placement algorithm in two-tiered WSN model is proposed in this thesis. This algorithm first constructs an optimum spanning tree for unlimited number of relay nodes. Then, a greedy strategy was put forward to remove some relay nodes from the tree. Under the restriction that each relay node must satisfy its communication capacity limitation, the greedy strategy aims to minimize the total energy consumption to prolong the lifetime of whole network.