The Research On Low-energy MAC Protocols In Wireless Sensor Network

Wireless Sensor Network is increasingly concerned and accepted by the field, which has the ability of sensing and processing physical data. Wireless sensor networks have been used in environmental monitoring, logistics management, industrial control and many other fields. The node integrated communication module, data storage module and sensor function. Wireless sensor network contains a large number of nodes, which can sense data timely and transmit to the information processing center. Data transmission process is one of the key technologies of wireless sensor networks real-time monitoring data, which determine the validity and reliability of the network.It is difficult to maintain wireless sensor network, due to the complexity of the deployment environment. Sensor nodes use batteries to provide energy. So the issues of maintenance sensor nodes need to be solved. It is necessary to reduce the energy consumption of sensor node. Reducing energy consumption will affect other performance index of the network, so different communication protocols are proposed according to different deployment environment. In this paper, the MAC protocol of wireless sensor network and the problem of the data conflict are discussed firstly. The traditional MAC protocol is divided into synchronization protocol and asynchronous protocol base on low duty-cycle. With the deepening of the research, the MAC protocol is divided into three categories based on the different channel access method.This paper proposed two MAC protocols based on the analysis of the existing MAC protocols, P-MAC and I-MAC. Unlike CSMA/CA, P-MAC using the receiving node sends random packet and sending node determine priorities through the random packets. So the retreat time has been dramatically reduced. P-MAC can solve the problem of hidden terminal in CSMA/CA. In I-MAC, this paper increased the number of antennas on the hardware structure. Then, the real-time monitoring method of conflict is designed based on the new hardware structure,in which two antennas structure optimizes the traditional retreat algorithm in order to improve the channel utilization and the throughput of network.