Performance Analysis Of MAC Protocol Based On Improved Backoff Algorithm

The MAC protocol(Media Access Control)for wireless networks is used to allocate limited communication resources among the nodes connected to the network,so that multiple nodes can share channel resources efficiently and without conflicts.Therefore,it plays an important role in the data transmission among the network nodes.Under CSMA/CA mechanism(collision avoidance based carrier sense multiple access),the node needs to transmit data in a competitive manner to seize the channel actively.This moment the node will collide with other nodes that seize the channel at the same time and.Moreover,as the number of users connected to the wireless network increases,the load of the network increases and the number of collisions also increases when the nodes transmit the data packets,which lead to the degradation of the system performance and the direct interruption of the data transmission in serious situations.According to above-mentioned problems in the process of data transmission,an improved adaptive backoff algorithm is proposed to solve the optimization of system performance in this paper when the number of users is large.The main works of this paper is as follows:Through the improvement of the classical binary exponential backoff mechanism,an improved adaptive backoff mechanism is proposed so that this mechanism can sense the changes of network environment adaptively when adjusting the backoff window.The mechanism takes into account three crucial elements.The idea of window partition is introduced,so that the value of competitive window is limited to the non-overlapping interval of different backoff stages.Freezing probability is added to make the model more consistent with the process of actual transmission in wireless channel.Parameters related to channel utilization are set to control the range of backoff window to reduce the number of collisions.The feasibility of the improved adaptive backoff algorithm is theoretically analyzed by establishing the two-dimensional Markov model and the model is evaluated by numerical simulations.The results show that the improved adaptive backoff algorithm proposed in this paper is better under high load network conditions.Secondly,in traditional networks,the nodes can continuously obtain energy supplement,or can replenish energy at any time in the case of interruptions,and the topology of the network is more stable.Therefore,the research of the MAC protocolis usually carried out in the ideal conditions,especially considering the performance of data transmission,improving the utilization of bandwidth and increasing the real-time performance of the network.However,the energy of the nodes in the energy-consuming network is limited and the topology of the network is dynamic.Therefore,the differences of the network structures make it necessary to design the suitable MAC protocol to control the data transmission process.Hence,based on the adaptive backoff mechanism,the energy loss in the network is also analyzed in detail in this paper.The energy consumed by each stage is analyzed separately based on the S-MAC mechanism of the energy-consuming network,and finally the energy consumed per second of each node is obtained.