Research Of Multiple-channel MAC Protocols Based On Power Control For Wireless Sensor Network

Wireless sensor networks can be perceived by a large number, as well as send andreceive data processing micro-sensors, self-organizing network topology. In order toachieve the object of monitoring real-time monitoring, sensing and transmission ofinformation to the task management platform. Compared to the traditional network,WSN (wireless sensor networks) to improve the area and performance monitoring,defense, environment, health, disaster relief and other fields has been widely used.MAC layer protocol is responsible for the access and distribution of wireless media,the communication process is one of the core support technology. In practice, thewireless sensor network limited from node energy, resources of bandwidth and thecommunication environment conditions, then, when the MAC protocol are designed,how energy efficiency and bandwidth utilization for data transmitted from the sourcenode to the base station becomes the main objective. Although there have been manyscholars are studied the multi-channel MAC protocol of large-scale networks, andachieved remarkable results, but still there are some problems. Although multi-channelMAC protocol has great advantages in network throughput, but channel switchingfrequently and control packet overhead heavy caused great waste of energy and causethe packet can not be transmitted timely; Furthermore, the limited energy of the wirelesssensor node, and the node will consume excessive energy premature death, therebyaffecting the entire network connectivity. How to ensure lower energy consumption ofnodes in the network, while the performance of data transfer is one of the key issues inwireless sensor networks. Therefore, finding an efficient multi-channel distributionpolicy and network of the power control is necessary.In this paper, combined with current development of wireless sensor networks,network throughput, latency and energy efficiency, and several other performanceindicators, in-depth study on the MAC algorithm, the main work is:Access existingliterature and related reference materials at home and abroad, analysis the performance in terms of energy consumption, network throughput and transmission delay, discussesthe large-scale wireless sensor networks, the advantage of multi-channel MACalgorithm in network capacity and identify shortcomings and needs further problemsexisting in MAC algorithms;Channel allocation stage, there is the problem ofconversion channel frequently in multi-channel MAC protocol, causing waste of energy.In response to this situation, we improve a multi-channel distribution mechanism ofreceiving node select the data channel. Receiving node compares the using list ofchannel received with local channel usage list after receives the RTS request from thesending node, select an idle channel for data transmission, and then the sending node isconverted into the data channel; Channel selection stage, if the receiving node not in thecontrol channel, the sending node will not receive the response packet, and the RTShandshake negotiation is fails, thus resulting in energy waste. For this situation,proposed strategy of neighbor notification can be alleviate this situation sent NCTS byneighbors after received RTS packet to notify the sending node where the receivingnode is;Improves a reliable power control algorithm. Receiving node according to theirsignal to noise ratio, the thermal noise power, interfering of neighbor nodes and QoSrequirements to calculate the optimal transmit power. At the high load network, nodescan reduce interference while saving energy consumption.