Design And Implementation Of Energy-saving And Power Control In Wireless Sensor Networks

In recent years, with its important scientific and practical values, wireless sensor network (WSN) attracted wide range attention of domestic and foreign research institutions and government organizations; it is considered one of the most influential technologies in the 21st century. In many sensor networks applications such as in monitoring the ecological environment and forest fire, nodes are deployed in a large scale, with limited battery power, while environmental constraints, and other factors lead to the replacement of the battery very difficult, so energy efficiency in wireless sensor networks is one of the most crucial technologies. In addition, dense distribution lead to the increase of packet collision, bit error rate, which results in reduction of the communications efficiency between nodes, network throughput and connectivity, therefore efficient power control technology in WSN is of great significance in part of ensuring the network coverage, reducing the power consumption of the nodes, and optimizing network performance.This thesis is supported by The National Natural Science Foundation of China. An energy-saving and power control design and implementation for wireless sensor networks is proposed in this thesis. It extends the lifetime of network and improves overall network performance.This thesis first discusses the research background and status of energy saving and power control home and abroad, indicates the significance of this thesis, and then following the protocol stack of node, the energy-saving and power control mechanism for WSN are designed and implemented considering characteristics of WSN and the hardware development Environment. When considering the energy-saving fraction, this thesis bases its study on energy-saving methods and analysis of energy consumption in each module of the sensor node, to reduce unwanted devices consuming energy, and to achieve longer sleep times controlled by MCU for each single node, and through network synchronization mechanism, realize synchronous sleep of the entire network. In the power control part, a power control mechanism in the MAC layer is built with the help of routing protocol, based on deep analysis of Ad Hoc network and wireless sensor networks power control mechanism. It calculates different transmitting power according to the distance between nodes. A table including optimal transmitting power and address of nodes is established. The transmitting power can be adjusted according to the address of next hop in data transmission. Through the analysis and evaluation of experimental data, it confirms the energy-saving and power control mechanisms are feasible and effective. Finally, the thesis summarizes the work conducted, guidelines for future research and work prospects.