针对IEEE 802.16系统中基于自适应多速率(AMR)语音编码器的IP语音(VoIP)业务，本文提出了一个自适应的功率节省策略。该策略周期性检测双向会话的语音帧信息，以此来判断上下行业务是否均进入语音静默期，然后自适应地调整功率节省模式参数。从能量节省、丢包率、系统信令开销方面分析了所提策略的性能，并且做了仿真实验。从理论分析和仿真结果可以看出，新策略在保证一定丢包率的基础上，可以比传统策略减少13.4%以上的能量损耗。

An adaptive scheme of power saving is proposed for the voice over IP (VoIP) services, which are based on the adaptive multirate (AMR) speech codec in the IEEE 802.16 systems. This scheme determines whether both of the uplink and downlink services enter the silence period through examining the information of speech frames in the twoway conversation periodically. Based on this, the parameters of the power saving mode are modified adaptively. Then the performance of the proposed scheme in terms of energy saving, drop rate and signaling overhead of system is analyzed. In addition, the simulation experiments are implemented. Through the theoretical analysis and simulation results, the new scheme shows that it reduces the energy consumption by more than 13.4% based on guaranteeing the drop rate of users compared with the conventional scheme.