Abstract: IEEE802.16 system uses Power-Saving Mechanism（PSM） to extend the battery life of mobile devices. However, existing PSMs adopted by IEEE802.16e/m employ exponentially growing sleep window, which sacrifice a lot of packet response time in exchange for energy efficiency. As a solution, this paper proposes a novel power saving mechanism namely nPSM, which adjusts the sleep cycle according to the average packet inter-arrival time. Whenever there is a packet arrives, the Base Station（BS） calculates the average packet inter-arrival time, and the information of measured inter-packet time is piggybacked on downlink packet sent to MS during the next communication between the BS and the MS, as the length of the subsequent sleep cycle. Combining numerical analysis and simulation experiments, the paper verifies that, under low traffic load, nPSM can achieve better energy efficiency while reducing the latency of packets compared to other PSMs for non-real-time services.

Key words: IEEE802.16m, sleep mode, non-real-time service, response time, energy efficiency

摘要： IEEE802.16系统中采用节能机制（PSM）来延长移动设备的电池使用寿命。针对非实时业务，IEEE802.16e和IEEE802.16m中的节能机制，通过令睡眠窗口指数倍增长来进行休眠，牺牲了大量的数据包响应时间来换取节能效果。为此，根据数据包到达的平均时间间隔，提出了一种动态设定移动终端（MS）睡眠周期的休眠算法nPSM。由基站（BS）在数据包到达时计算数据包平均到达间隔，并在下一次与移动终端通信过程中，通过下行数据包以捎带的方式将该信息传递给移动终端，作为后续休眠周期的长度。结合数学分析和仿真实验，验证了所提休眠算法相比现有针对非实时业务的节能算法，在低通信负载下，在减少数据包响应延时的同时提高了节能效果。

关键词: IEEE802.16m, 休眠模式, 非实时业务, 响应时间, 节能效率