Improvement Of The Priority Level Of The S-MAC Protocol Based Of The Number And Energy

The WSN(Wireless Sensor Network) is a multi-hop self-organized network systems, including sensors, perception of the object and the observer. Wireless sensor network works by the deployment of a large number of sensors in the monitoring region nodes using wireless communication and perception, acquisition and processing of information sent to the observer.In WSN, according to certain mechanisms, the data in the source node is divided into different priorities, with priority information and data encapsulated in the data frame transmission between network nodes, in order to achieve whether it is the source node or in the node to quickly transfer important data. In wireless sensor networks, MAC protocol in sensor network protocol underlying part, responsible for the management, coordination, users share the channel resources, thence, have a greater impact on the performance of sensor networks. Thesis IEEE 802.11 data frames combined data priority and energy priority on the S-MAC protocol has been improved to solve the data priority carryover problem. When data is transmitted, the node may adjust the contention window based on the priority of transmission data and energy, combined with the network load conditions, so that the high priority data priority transmission network, so as to achieve the dispersion competitive pressures to reduce the number of collisions of the purpose.The experimental simulation platform NS2, the performance test for the improvements proposed in this thesis. The experimental results show that the improved protocol during the transmission of high priority data, the transmission delay significantly reduces balance the network load to a certain extent, extending the network lifetime.