在能量有限的无线传感器网络中，节点睡眠与节点间的数据快速转发是一对矛盾.星型网络既节能又容易控制，但网络面积太小.该文提出了一种无需专用路由器的节能中转法，将星型网络扩展为内外二层的结构，控制面积是星型的4倍.主要采用了以下措施：1）拓扑结构控制算法将网络节点以控制器为圆心分为内外二层，外层节点以内层节点作为中转点，从而简化了路由，优化了路由能耗；2）节能时序控制.首先，节点从睡眠到苏醒过程中采用了时间分段的顺序，减少了监听时间和消耗的电流；其次，内层节点的短时间监听与外层节点的发送序列协调配合，既实现了常态下的低能耗通信，又解决了应急状态下的快速同步.经测试和仿真结果表明，所提出的二层低功耗无线网络及其控制方法是可行的，节点低功耗和网络延时特性满足设计要求.
In a wireless sensor network with limited energy, node sleep and data forwarding between nodes are a pair of contradictions. Wireless star network is both energy efcient and easy to control, but the network size is small. This paper presents an energy-efcient transfer method without a special router, the star network is extended into an internal and external two layer structure. So the control area increases to four times that of the star type. The following methods are used: 1) The topology control algorithm divides the network nodes into internal and external two layers with the center of the controller as the center. Inner layer nodes are used as routers by outer layer nodes. It simplifes routing and optimizes routing energy consumption. 2) Energy saving timing control. First, the nodes use the sequence of time segments from sleep to revival, reducing the listening time and the consumption of the current. Secondly, the short time monitoring of the inner node is coordinated with the transmission sequence of the outer node. It can not only realize the low energy communication in the normal state, but also solve the fast response in the emergency state. Test and simulation results show that the two level low power wireless network and its control method proposed in this paper are feasible, and its low power consumption and network delay characteristics meet the design requirements.
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