Wireless Sensor Networks Forwarding Priority And Adaptive Backoff Algorithm

Many small size nodes compose wireless sensor. Currently there are more and moreareas have started using wireless network sensors, this technology not only makes our dailylives a relatively big change, but also an important outcome of the current scientific andtechnological development. This research bases on the working principle of wireless sensor，the backoff algorithm principle of wireless sensor networks and the NS and MATLABsimulation and design an improved backoff algorithm.First of all, a simple Markov chain model is quoted to analyze the back-off mechanism inS-MAC protocol, analyze the deficiencies of the S-MAC, point out the main parameterswhich affect the system throughput by formula.Secondly,For wireless sensor networks treat different nodes with different principle, bothin order to protect communication forwarding and the real-time multimedia data’stransmission, you need to give a competitive advantage to the forwarding node, give thedifferent priority of competition window to different nodes, introduce priority factor for eachnode to measure the priority level of the nodes, the priority factor of the node depends on thetraffic load and type.Simulation results show that the algorithm protects the transmission ofthe real-time multimedia data.Finally,in order to reduce the conflict, latency and energy consumption, improve systemthroughput, first analyze the traditional energy classification algorithms, and then analyze theadaptive backoff algorithm, that the former listens to the idle times and the times of the nodessending fails, dynamically reduces or increases the contention window, but in the busysystem, the contention window can not be changed, can not adapt to the network, the latteradaptive backoff algorithm bases on the probability of conflict and adjust the contentionwindow, but the incident is not even appear sensing, often with some unexpected, so thenetwork traffic is not in a stable long-term targets, the algorithm does not bring the idlelistening energy loss into account, when the network is idle, the algorithm will cause energywasting, when the network is busy, the probability of conflict will lead to larger, so weproposed an adaptive combines energy classification algorithm, dynamic and static adjust thecontention window to meet the busy network, increase throughput, reduce latency, reduceenergy consumption, reduce the number of nodes in conflict.By considering energyefficiency, this paper introduces the alert factor, when the node energy consumption is morethan the warning line, excessive consumption of nodes at this time obtain competitivedisadvantage to access channel, making the residual energy increasing.Simulation resultsshow that the algorithm increases the successful rate of transmission,increases the systemthroughput,reduces energy consumption and prolongs the network lifetime.