Research On MAC Protocol For Application Of Traffic Monitoring Based On Fuzzy Clustering In WSN

Wireless Sensor Network(WSN)is composed of a large number of distributed sensor nodes in a specific area,and transmit data to Sink through the form of wireless sensor.Because of its unique advantages,WSN has been widely applied in military defense,environmental monitoring,industrial technology and intelligent transportation system,etc.With the development of traffic in today's society,the demand for traffic monitoring is also increasing by reason of vehicle rapidly increase.Wireless sensor network,with its own characteristics,which has been developed rapidly in application of traffic monitoring.The MAC protocol is the important technology of wireless sensor network.So,designing a MAC protocol for traffic monitoring has great significance.In order to solve the real-time issue of bursting data in traffic monitoring,a Medium Access Control(MAC)protocol based on fuzzy clustering called FC-MAC is proposed in this paper.The contents of FC-MAC protocol can be divided into the following several aspects.Firstly,this protocol works by alternating between TDMA and CSMA/CA,which not only ensures periodic data transmission,but also enhances the real-time property of bursting data.The method of fuzzy clustering is introduced in the phase of CSMA/CA.Cluster heads assign different levels of priority according to vectors through fuzzy clustering,and nodes decide access parameters by category.So,it can dynamically divide access priority,decrease the collision probability,make bursting data with higher priority are transmitted earlier.In the meantime,it ensures the real-time performance of the whole network.Secondly,designing a kind of frequency multiplication algorithm,which realize the different frequency in different clusters.It uses to eliminate communication interference between different clusters.In addition,according to the timing slot allocation strategy and the parameters of the frequency multiplication algorithm,a method of hierarchical random delay(HRD)is presented.It makes the cluster headrandom delay several time block in initial stage of network and divides the stage of SEND hierarchically,which reduces the number of nodes accessing to Sink node simultaneously and decreases the data delay caused by backoff mechanism.Finally,simulating crossroad through NS-2 platform environment,and setting parameters of simulation based on the situation of crossroad.Simulation results showed that FC-MAC performed excellently on the delay of bursting data and the throughput of network,respectively,was more adaptive to the change of network traffic.