| Sensor networks constitute a special kind of ad hoc network. Fostered by recent advances in Micro-electro-mechanical system (MEMS) and wireless communication technology, sensor nodes can be made very inexpensively while maintaining certain calculation abilities. Deployed in a large numbers and through collaborative effort, these sensor nodes can complete many sensing tasks, data processing and communication of useful information. Because sensor nodes are typically very small and powered by irreplaceable batteries, energy control becomes the primary, and also the most challenging problem in designing sensor networks.; In this thesis, the preliminary frame work of a Directed Optimal Energy-efficiency Routing protocol (DOER) is established, its goal is to develop a global energy control protocol that finally prolongs network lifetime while achieving energy balance among sensor nodes. DOER synthesizes factors of residual energy and state switching and reaches a tradeoff between path optimization and global energy balance.; DOER protocol includes four parts which are respectively: DOER-NS (Neighbour Searching), DOER-NIT (Neighbour Information Table maintenance), DOER-SS (State Switching) and DOER-RS (Route Selection).; The theory analysis and experiments of DOER protocol are finished by Matlab and simulated on OPNET Modeler 10.0, experiments are designed under different network topologies and different network salabilities. Observations are presented and analyzed. |
