大多數的無線系統都有支援省電模式，但在規格書中卻僅制定相關的訊息傳遞和運作流程，對於啟動與離開省電模式的切換機制並沒有明確的規範。本文將提出一個啟動與離開省電模式的切換技術，除了針對不同的連線類型採用不同的判斷方式，也同時考慮了連線的佇列狀態、資料封包的到期時間、整體資料的傳輸時間，以及用戶端的實際頻寬等環境變數，藉此找出最適當的模式切換時間點，以提升省電模式效益。

Power-Saving mode is supported in most wireless systems. However, only the control messages and operation flows of power-saving mode are clearly defined in the specification. There is no specific switching mechanism to activate and exit power-saving mode defined. In this paper, an operative power-saving switching method is proposed to identify the most ppropriate timing for mode switching. This novel method adopts different criteria for different connections. The operational parameters such as the status of queues, maximum packet latency, total data transmission time, and actual bandwidth granted are considered as well. Simulation results show that the proposed method enhances the efficiency of power-saving mode obviously.