無線中繼網路(wireless relay networks)由於採用多中繼點傳輸(multi-hop transmission)因此可提供傳統單點傳輸(single-hop transmission)網路所沒有的特性，例如大範圍的訊號涵蓋面積(signal coverage)和傳輸效能(throughput)的提升。但是無線中繼網路中也存在著許多問題，例如較長的封包延遲(packet delay)及不必要的重新傳輸(retransmission)。有一些研究提出一些方法來使得無線轉送網路的傳輸更加順利，但是這些方法卻會產生其它的問題，例如效能受限等。本篇論文提出一個基於點對點(hop-by-hop)傳輸的轉送方法，此方法可以同時降低封包延遲並且提升效能。為了使此方法不產生其他的問題，我們另外提出了兩個機制來協助它，分別是流量控制(flow control)以及資料轉送(data forwarding)。藉由此方法的落實，無線中繼網路便可以在低成本的前提下產生最高的效能。

Wireless relay networks which adopt multi-hop transmissions can provide additional attributes to benefit traditional single-hop transmission, such as coverage extension and throughput enhancement. But some overheads, such as feckless retransmission and longer transmission delay caused by multi-hop radio links, need to be addressed in the relay networks. There are some mechanisms proposed to reduce packet delay and improve throughput of multi-hop relay transmission, but these schemes causes other problems, e.g. lower throughput. This study proposes a novel relay transmission scheme to shorten the transmission delay without problems caused by the other proposed mechanisms. There are also two assistant mechanisms proposed in this study to solve system problems in the relay networks. Then the proposed scheme can make the relay networks achieve high throughput and low cost at the same time.

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