The optimal backoff window size and contention window size are given, and the transmission efficiency is calculated by analyzing the collision probability of contention request. 通過(guò)對競爭請求的沖突概率進(jìn)行分析,推出了回退窗口和競爭窗口的最佳分配尺寸,并計算了不同業(yè)務(wù)流數量下系統可達到的最大傳輸效率。