Research On Energy-efficient Clustering Routing Protocol For Wireless Sensor Network

Since the seventies of the 20 th century, wireless sensor network has been increasingly recognized and applied. In recent years, at the rise of “Internet of things”, wireless sensor network has penetrated into all fields, such as industry, agriculture, military, medical, daily life and so on. However, due to the energy constraint of sensor nodes, energy efficiency becomes the most important factor to limit the development of wireless sensor network.Therefore, it is very necessary to design energy efficient routing protocols.In order to solve the “hot spot” problem caused by unbalanced energy consumption of wireless sensor network, a unequal clustering routing protocol based on energy consumption balance(ECBUC) is proposed, considering residual energy and location information of each sensor node. An energy factor is introduced into the selection of candidate cluster heads,which makes the nodes with higher residual energy become cluster heads. In the process of clustering, the distance between cluster head and sink node controls the cluster radius, so as to achieve unequal clustering. In the process of routing between clusters, a path factor is put forward, considering the cluster head’s residual energy and location information. The path is established by selecting clusters with higher path factor, which ensures that the energy consumption of the route is balanced, and the network lifetime is prolonged. Simulations show that ECBUC protocol balances the energy consumption of each phase of the network.Compared with EEUC protocol, the network lifetime has been prolonged by 22.29%. This protocol’s performance is stable, and it can well adapt to the complex environment.Aiming at improving data transmission reliability and energy efficiency of wireless sensor networks, an energy efficient unequal clustering routing protocol based on network coding(UCBNC) is proposed. This protocol is based on ECBUC protocol, combined with random linear network coding and multi-path routing. Firstly, a complete random network coding scheme is proposed, combining random network coding with the unequal clustering routing. The cluster heads encode packets from member nodes after data fusion. Multiple encoding packets generated by the cluster head are transmitted to multiple paths. Each intermediate node recodes data packets and puts them forward, until sink node can decode and get the raw data. In the reference of ECBUC protocol, the network retains ECBUC’s clustering scheme. The original single path routing is developed as a multi-path routing,which can increase the coding opportunities and balance energy consumption of each node,so that the data can be reliably and efficiently transmitted in the network. UCBNC protocol takes the advantages of network coding and unequal clustering routing to improve reliability and energy efficiency of the data transmission. In simulation experiments, UCBNC protocol is compared with ECBUC protocol and the multi-path routing protocol based on ECBUCprotocol. The comparison of successful delivery rate, normalized redundancy,standardization of energy consumption and network lifetime indicate that UCBNC protocol can improve the network reliability. In the data transmission process, energy is used more effective. The energy efficiency of network is improved.The three main innovations of this thesis are as follows:(1) In the process of clustering, firstly, an energy factor is introduced into the selection of candidate cluster heads, which makes the nodes with higher residual energy become cluster heads. Then the competition algorithm divides the network into unequal areas to solve the “hot spots” problem and balance the energy consumption.(2) In the process of routing between clusters, a path factor is put forward, considering the cluster head’s residual energy and location information. It coordinates the communication cost between clusters and the energy distribution of the network.(3) A random network coding scheme is proposed combining the random network coding with the unequal clustering routing, to implement network coding in data transmission. Based on the structure of clustering wireless sensor network, a partial network coding routing scheme is designed to make data transmission more reliably and more efficiently, finally, to improve the reliability and energy efficiency of network.