在論文中我們提出了兩種動態調整競爭週期與免競爭週期交替的方式：碰撞導向與工作站數量導向的工作模式。碰撞導向的方式是利用擷取點內部的計時器來估算頻道碰撞的次數，當擷取點內部的計數器為零，則擷取點將主動介入並發起免競爭模式；而工作站數量導向主要是讓DCF的競爭時間可以依照工作站數量的多寡而有所調整。希望藉由這兩種方式使得網路資源在分配上可以擁有較大的彈性，並提供不同等級需求的工作站所需要的效能。在模擬結果中可以發現當工作站的數量越多的時候，使用工作站數量導向的方式可以讓工作站得到較好的效能；而碰撞導向的方式若單獨使用時效果並不明顯，但是若與目前802.11現有的模式搭配時，可以使得系統資源使用的更有效率，並且可以增加具優先權工作站的效能。

This paper proposes two kinds of schemes to adjust the IEEE 802.11 DCF (Distributed Coordination Function) and PCF (Point Coordination Function) period dynamically ：Collision oriented and Mobile Node oriented . The Collision oriented scheme employ a counter which in AP (Access Point) to estimate the collision times. When then counter count down to zero , AP will broadcast the beacon frame and begin the PCF. The Mobile node oriented scheme can adjust the DCF period dynamically according to the number of mobile nodes. In this paper we will simulate these schemes and discuss the result.

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