Research On Routing Protocol Of WSN In Sewage Monitoring System

With the development of economy,the discharge of municipal sewage is increasing,which requires the efficiency of sewage treatment higher and higher.Compared with traditional monitoring technology,the sewage monitoring system based on wireless sensor network has lower cost and better real-time performance.Routing protocol is one of key issues in wireless sensor network research,which directly affects network performance and monitoring quality.Through extensive literature investigation and comparison,we focus on the suitable wireless clustering routing and opportunistic routing in depth,and design the corresponding improvement strategies in this paper.The main research contents and contributions of this paper are as follows:In order to extend the life of the network and monitor the conventional water quality parameters for a long time,a novel clustering routing protocol based on firefly algorithm is designed to solve the problems of unreasonable clustering and random cluster head selection in traditional LEACH protocol.This protocol introduces the idea of centralized clustering,and applies firefly algorithm to optimize clustering of all sensor nodes.At the same time,a new cluster head selection scheme is proposed overall considering the node position and residual energy.These works improve the rationality of network clustering and cluster head selection efficiently.Experimental simulation results show that the network life of the novel clustering protocol is nearly 6 times longer than that of the traditional LEACH clustering protocol.The inherent clustering characteristic of LEACH protocol leads to slow data response and transmission efficiency,which makes it unsuitable for large data traffic and high real-time requirements.On the other hand,opportunistic routing can make full use of the features of wireless channel broadcasting and effectively improve the performance of data transmission through reactive multi-path algorithm.But the traditional opportunistic routing has the problem of unreasonable selection of candidate forwarding nodes.Therefore,energy-first opportunistic routing(EFOR)and low delay opportunistic routing(LDOR)are designed respectively in this paper.In the EFOR protocol,the energy consumption model under the non-ideal data link layer is constructed firstly,and the expected energy consumption of packet transmission from each node to the destination node can be calculated and obtained.Then,a new candidate forwarding node selection algorithm based on optimal energy consumption is proposed.Finally,the candidate forwarding nodes are prioritized and ranked according to the expected energy consumption and remaining energy.In the LDOR protocol,we construct the end-to-end delay model firstly,according to the opportunity forwarding framework,and calculate the expected delay for each sensor node in network.A delaybased candidate forwarding node selection scheme is then proposed.Finally,the priority ranking is performed according to the expected delay and the transmission success rate.Simulation results demonstrate that the opportunistic routing protocol can effectively balance the energy consumption of each sensor node in the network,prolong the network life,and reduce the network transmission delay obviously.Microorganisms in sewage play an important role in indicating the quality of sewage treatment.In order to use the limited wireless bandwidth reasonably and ensure the real-time and reliability in water quality monitoring on-line system,an image content-associated opportunity routing protocol is designed in this paper.Firstly,a fast moving target detection algorithm is proposed to extract the indicative microorganisms in the video image.Then,a ranking strategy for detection results is presented,which reduces the network data flow and operation load.Finally,the low-delay opportunistic forwarding strategy is adopted for high-priority data packets;and the energy-first opportunistic forwarding strategy is adopted for low-priority data packets.Simulation results show that by using of this routing protocol,network survival time increased by nearly 50% and transmission delay reduced by 20% of important data,compared with traditional and improved opportunistic routing ones.