基于信标同步触发的机械振动WSNs传输休眠时序调度方法

Transmission-sleep timing scheduling method based on the beacon synchronous trigger for machine vibration wireless sensor networks

针对IEEE 802. 15. 4协议中载波侦听多路访问/冲突避免机制(CSMA-CA)在机械振动无线传感器网络大量原始数据传输需求下存在多次载波侦听导致高侦听能耗、隐藏节点问题导致高重传能耗等问题,提出一种基于信标同步触发的机械振动无线传感器网络传输休眠时序调度方法。首先利用在信标网络中广播信标帧具有全网周期性同步的特点,对超帧结构进行设计,为物理上具有分散性的各节点接收时序调度信息提供基本的时间同步条件;然后以各节点网络短地址为调度信息并利用信标可携带负载的特点,将调度信息载入信标进行广播,实现低开销的调度信息通知机制;最后,各节点根据调度信息进行数据传输、休眠时序调度,改善并优化CSMA-CA在传输大量原始数据时存在无谓的传输能耗浪费缺陷。较之CSMA-CA,实验结果表明所提方法能有效降低机械振动无线传感器网络数据传输能耗。

Aiming at the problems in the carrier sense multiple access with collision avoidance （CSMA-CA） in IEEE 802.15.4 under the mass raw data transmission requirement in mechanical vibration wireless sensor networks（WSNs）, such as the multiple carrier sense caused high listening energy consumption and hidden node caused high retransmission energy consumption, a transmission-sleep timing scheduling method was proposed based on the beacon synchronous trigger for machine vibration wireless sensor networks. The feature of whole network periodic synchronization in beacon-enabled networks was utilized to provide the basic time synchronization condition for distributed nodes, and to design a super frame structure, ensuring the time consistency of each node for receiving the scheduling information. Using the network short address at each node as the scheduling information and utilizing the ability of carrying payload of beacons to broadcast the scheduling information with beacons, the low consumption overhead scheduling information notification mechanism was realized. Finally, at each node the decision of whether transmitting data or sleeping was made according to the scheduling information to improve and optimize unnecessary high transmission energy consumption defects for the CSMA-CA during transmitting large amounts of raw data. Comparative experiments on the CSMA-CA were carried out and the experiment results indicate that the data transmission energy consumption of the machine vibration wireless sensor networks can be reduced effectively by the method.