本論文研究了時延約束自動重複請求（ARQ）協議的性能。特別是，我們提出了一種快速 ARQ 協議，其中，為了增加端到端吞吐量，省略了一些 ARQ 反饋信號和連續消息解碼。我們用單用戶延遲信道狀態信息（CSI）來描述雙用戶廣播擦除信道（BEC）的容量區域。我們假設一個接收器不向其他兩個節點（另一個接收器和發送器）提供其通道狀態，而另一個接收器以單位延遲全局顯示其狀態。在上述情況下，我們使用雙階段網絡編碼作為優化方法，並將快速 ARQ 協議與第二階段相結合。我們首先利用先前在具有單用戶延遲 CSI 的 BEC 上的工作推導出具有反饋的機會性三相網絡編碼的速率對。然後，我們設計了用於兩階段機會網絡編碼中間歇性反饋的快速 ARQ。在這項工作中，我們假設傳輸概率是固定的，並調整反饋概率。推導結果與上限進行比較並且非常接近。結果表明，間歇性反饋可以減少反饋延遲，並且提高網絡容量。

This thesis studies the performance of delay constrained automatic repeat request (ARQ) protocols.
Particularly, we propose a fast ARQ protocol where, to increase the end-to-end throughput, some ARQ
feedback signals and successive message decodings are omitted. We characterize the capacity region
of the two-user broadcast erasure channel (BEC) with single-user delayed channel state information
(CSI). We assume one receiver does not provide its channel state to the other two nodes (the other
receiver and the transmitter), while the other receiver reveals its state globally with unit delay. In the
above case, we use two-phase network coding as the optimized method and combine the fast ARQ
protocol with the second phase.We first derive rate pair of the opportunistic three-phase network coding
with feedback with previous works on BEC with single-user delayed CSI.Then,we design the fast ARQ
for intermittent feedback in two-phase opportunistic network coding.In this work,we assume that the
transmission probability is fixed and adjust the feedback probability.The result is compared with the
upper bound and very closed it.According to the result,intermittent feedback can reduce the feedback
delay and improve network capacity.

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