一种改进的IEEE 802.11节能协议

针对IEEE 802．11DCF协议节能模式(802．11PSM)节能性能受网络中流数目影响严重的缺点，提出了一种改进的802．11PSM 节能协议。通过采用一种时间-报文混合驱动的分布式无线网卡(NIC)动态关闭机制，使802．11PSM协议中那些在beacon周期内一直处于活跃状态的节点在当前通信与自己无关时进入睡眠状态来节省能耗，从而大大降低了流数目对协议节能性能的影响。近似分析和仿真表明，当业务流数目较多且负荷较大时，802．11PSM 与802．11PSM相比有明显的节能效果。802．11PSM 的吞吐率性能和时延性能仍与802．11PSM大体相当。

A Modified Version of IEEE 802.11 Power-Saving Protocol

To overcome the flaw in IEEE 802.11DCF protocol with Power Save Mode (802.11PSM), whose power-saving performance is severely affected by the flow numbers in the network, proposes a modified protocol called 802.11PSM+. The new protocol uses a time-packet hybrid-driven distributed dynamic switching-off mechanism on wireless network interface card (NIC). It makes those active nodes in the beacon interval go into sleep mode to save power whenever the current transmissions on the channel are irrelevant to them, whereas they will always be active in 802.11PSM. 802.11PSM+ dramatically reduces the negative effects of flows on its power-saving performance. Approximation analysis and simulation results show that when the network load is rather heavy and the numbers of active flows are high, 802.11PSM+ has much better power-saving performance than that of 802.11PSM. The throughput and delay performance of 802.11PSM+ is still almost the same as that of 802.11PSM.