Wireless Sensor Networks, Energy-sensitive Technology Research

Wireless sensor network (WSN), which is a composition of sensor, MEMS and networks technologies, is a brand-new technology about information acquiring and processing. Due to its flexibility, robustness and intelligence, it will be used in a variety of applications such as environmental monitoring, military, medical, and public safety systems.A key challenge in wireless sensor network is using the limited energy in a reasonable way in order to maximize the network lifetime. Based on the view of energy-aware computing, this thesis makes the following contributions:(1) Energy awareness of WSN is overviewed from both nodes layer and network layer, then the application of energy-aware technologies for sensor hardware, topology control, network clustering, routing and data aggregation are respectively introduced.(2) An energy efficient topology control protocol named EEASNT is proposed, which extends the scheme of elicitation to hierarchical sensor network topology. By transiting from three states: active, sleep and listening, sensor nodes can maintain the connectivity of sensor net in a self-adaptive and energy efficient way. The simulation results prove the performance of EEASNT.(3) A network flow based model of network lifetime for WSN is built. By analysis of the model, energy-aware routing and data aggregating are proved to be the two crucial factors to save energy on network layer. Finally, a network-based comprehensive energy-aware solution is presented, the performance of which is also proved by simulations.(4) An application example of battlefield surveillance system is designed, which verifies the effectiveness of the above proposed WSN energy-aware technologies.