Research And Implementation Of Routing Technology In Wireless Sensor Networks

This thesis is based on the project of the National Development and Reform Commission—Node of IPv6 Wireless Sensor Networks, focusing on the routing technology and the issues of sleeping schedule in wireless sensor networks.The first part of this article gives an overview of research on wireless sensor networks, including the origin, the development, the character and the application of wireless sensor networks. The key issues of routing protocols and sleeping algorithms in wireless sensor networks, such as the factors which affect the design are discussed with emphasis, and some current typical routing protocols and sleeping algorithms are analyzed.In the second part, aiming at the issue of sensing coverage and connectivity in wireless sensor networks, a complete new algorithm is proposed, on the premise of sensors' position aware. The algorithm adopts a clustering method and a decentralized sleeping method to reduce the energy consumption of wireless sensor networks and to prolong the lifetime of wireless sensor networks furthest. The fully connected clustering method ensures that all nodes in a cluster can communicate with each other within one hop. The result of simulation indicates that the algorithm can maintain sensing coverage and connectivity in wireless sensor networks, while the energy consumption of sensor networks is small.In the third part, basing on the actual requirements of the project, a tree based energy efficient routing protocol TREES is designed. This protocol constructs a tree based network rooted from the sink node, and the nodes decide whether to active or not, according to two qualifications. One is if the nodes have any following nodes. The other is the effect on the coverage of the networks when the nodes sleep. The result of simulation shows that TREES lowers the energy consumption as well as guarantees transmission and conserves needed coverage ratio so that lengthens the network lifetime effectively.The last two parts of this article emphasize on the design and the implementation of the routing protocol S_TREES, which is a part of the project named Node of IPv6 Wireless Sensor Networks. In STREES some mechanism of TREES is simplified. S_TREES exits as a module in the system, using interfaces to exchange information with application module, SingleHopManager module, power control module and MAC module. The debugging of routing module on PC, Mica2dot node and self-designed node, the interfaces testing among routing module, application module and lower layer module, as well as the system testing between the routing module and the other modules have been accomplished. The testing results shows that the routing module functions well.