多重躍進網路使用 carries sense multiple access (CSMA)協定時，會因為嚴重的隱藏節點問題，使得多重躍進網路裡每個節點的傳輸率分配不平均，甚至有些節點傳輸率接近為零，造成傳輸效能低落的現象。為了解決這個問題，Benveniste提出快速遞送 (express forwarding, EF)協定來提升多重躍進網絡的傳輸效能。本篇論文的研究目的是提出一個適用於快速遞送協定的數學模型，文中以各節點之backoff counter剛開始倒數的時刻為觀察點，依據快速遞送協定的運作方式，定義出各節點觀察到的通道狀態，推導出狀態發生機率，再從各個節點的狀態發生機率來引出各節點傳輸率。文末以系統模擬來驗證分析的正確性，由數值分析結果可知，本論文提出的分析模型可以根據節點周圍干擾狀況，準確的估計使用快速遞送協定的多重躍進網路中各節點傳輸率。

The individual throughput of each node for a multihop wireless network is unfairness due to the serious hidden node problems. An express forwarding (EF) protocol has been proposed to enhance the throughput of the multihop wireless networks. In this paper, we propose an analytical model to analyze the individual throughput of each node employing EF protocol. Base on the concept of [9], the observation point is set at the moment of begging of a backoff counter. According to the observation point, the channel state and the state occurrence probability of the each node are then defined and computed. We use the state occurrence probability to derive the individual throughput of each node. Simulations are conducted by NS-2 to verify the accuracy of the analytical model. The results show good match between simulation and analysis.

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