如何通过网络的多跳中继把传感器节点收集的信息快速、高效地传输至基站,是无线传感器网络的基本问题.研究发现,MAC(media access control)层的睡眠调度和无线信道的不规则性均会对路由协议的效率产生较大影响.虽然传统分层设计的网络协议有着模块化的优点,但各层之间的相互独立却导致网络的整体性能不能达到最优.此外,已有协议通常采用牺牲时延以提高能量效率的方法,会给时延敏感系统带来不能容忍的端到端时延.提出一种时延受限且能量高效的跨层路由协议(delay-constrained and energy-efficient cross-layer routing简称DECR),该协议在做出路由决定时考虑MAC层以及链路层的相关信息,其目标是在将端到端时延控制到低于预定上界的前提下最优化节点的能量效率.理论分析和实验结果表明,所提出的跨层路由协议具有较好的性能.
It is essential for wireless sensor networks (WSNs) to forward information collected by sensors to the sink quickly and efficiently through multi-hop relay. It is found that both duty cycle in the media access control (MAC) layer and the radio irregularity affect the efficiency of routing protocol greatly. Though traditional layered protocol has been proven to have the advantage of modularity, its whole performance cannot achieve its optimal performance since each layer works independently. Furthermore, most existing protocols that sacrifice time to improve energy-efficiency will bring unacceptable end-to-end delays to time-sensitive systems. This paper proposes a delay-constrained and energy-efficient cross-layer routing protocol (DECR), which takes into account related information of MAC and link layers when making routing decisions where the objective is to maximize the energy-efficiency of a node on the premise that end-to-end delay is restricted to the predefined upper bound. Both analysis and simulation results show that DECR performs well.