A Routing Protocol Based On Leach Protocol In Wireless Sensor Network

Wireless sensor network (WSN) technology is one of the most advanced technologies in current sensory monitor research area. The WSN can monitor a target area through wireless network receiving signals from thousands of sensor nodes previously laid in the target regions. Besides, the WSN is also a self-organizing network. These advantages let the WSN has the ability of both controlling a large territory, and also can process the data at the first time. Therefore, the WSN technology is highly applied in both mercantile and military area. Besides, the advantages of the WSN’s monitoring ability also let itself get lots of attention in the biomedical and environmental research areas. Currently, both China and the other developed countries, such as American and Russia have investigated lots of research resource on the development of the WSN technology.The WSN technology can be further divided into several sub-technologies such as:the routing protocols programming, the data synchronization, the data emerge, source localization,etc. This thesis is aimed to develop an "energy conserving" routing protocols meet the application requirements. Energy conservation is a very important issue for the WSN, because the energy resource of the sensory node is always limited. Once the energy is exhausted, the certain node will out of work, and let "dead node" emerge in the whole monitor network under the WSN. Therefore, the research about the developing an "energy conserving" routing protocol becomes a crucial issue for the developing and utilization of the WSN technology.Several kinds of routing protocols can write for WSN, such as the hierarchical routing protocols. My thesis chose to optimize the LEACH (Low-Energy Adaptive Clustering Hierarchy) protocols. It is a typical kind of hierarchical routing protocol. The advantage of the LEACH is that it is relative energy-efficiency and signal stable. The disadvantage of the LEACH is that it is uneven distributed, and the LEACH does not take into consideration about the residual energy and distance-related issues when it is clustering. Therefore these disadvantages of the LEACH protocols seriously hampered the utilization of the WSN. In my current thesis, I try to optimize the traditional LEACH algorithm, and provide a possibility for adapting the WSN technique into special circumstances, such as roadways, and forests.My updated LEACH was revised majorly in two aspects:the cluster head selection and the signal transmission scheme optimize. The longer distance of the node head located from the base station is, the more the energy will be consumed on the signal transmission. Because the energy resource is limited, the more remote node head is more likely to exhaust into "dead node". Traditionally, the LEACH did not take the distance into consideration. It is necessary to comparing the random number of cluster heads with a certain thresholds, and therefore traditionally the WSN use a homogeneous head node for all area. However, This paper designed to use heterogeneous head node:the larger head node used for the near location, while the smaller one used for the more remote places. In this way, the whole network can reduce the chance about the "dead node", and also can be more energy effective. At the same time, it will re-election the cluster heads after finished select cluster head nodes. It will change cluster heads which is less than the average energy cluster and make the node of low remaining energy does not become a cluster head. Secondly, I tried to use "multi-hop" to substitute the traditional "single-hop" transmission scheme to deliver the signals between clusters. Comparing with the traditional LEACH protocol, my updated LEACH significantly save more energy for the signal communication between the remote nodes and sink nodes, and also significantly enlarged the control transmission range of the WSN. All the simulation results show that the updated LEACH protocol in this thesis under the MATLAB software, has advantages as:energy conservation, prolong the working time, high stability. These advantages of the updated LEACH protocol may further help the WSN technique further developing and utilizing in a wide circumstance.