人体局域网MAC层节能机制研究

Research on Energy-saving Mechanism of MAC Layer in Body Area Networks

近年来,随着无线传感技术的快速发展和人们对医疗服务需求的增加,人体局域网(BAN)逐渐成为国内外研究的热点。在人体局域网中,各种体征信号采集节点要求植入体内或置于体表,并长时间对人的体征信号进行采集,这需要节点有足够长的生命周期。因此人体局域网节能机制研究是人体局域网研究中的重点之一。人体局域网MAC层决定着无线信道的使用,因此对MAC层协议的研究与优化是功耗控制的重点。本文系统地介绍了MAC层节能机制的原理,重点研究了通过降低数据包冲突降低功耗的方法,提出了一种基于预约机制的MAC协议,在IEEE 802.15.6标准基础上,新定义了预约类型帧,调整了超帧结构。仿真结果证明在节点数目较多或数据量较大的情况下,能有效避免数据包冲突,节能效果明显。

In recent years, with the rapid development of wireless sensor technology and people to increase the demand for medical services, body area network （BAN） has become a hot research at home and abroad. Various of human vital signs acquisition nodes, which in the vicinity of, or inside, a human body, must have long lifetime so that they can acquire the vital signs for a long time. Therefore, research on energy-saving mechanism in BAN is one of the key points in body area network research. BAN MAC layer determines the use of radio channel, so the study and optimization of the MAC layer protocol is the focus of power control. This paper systematically introduces the principle of the energy-saving mechanism of MAC layer, focusing on the method that reducing power consumption by reducing packet conflict and proposes a new reservation strategy- based MAC protocol which defines new reservation frame type, adjusts the superframe structure basing on the IEEE 802.15.6 standard. Simulation results show that it can effectively avoid packet collisions when the number of nodes or data is large and energy-saving effect is obvious