藉由減少HARQ RTT來增進TCP在LTE中的表現

Abstract

在科技的進步下，伴隨著智慧型手機和平板電腦的推陳出新，行動網路已經如同固網般，是大多數人不可或缺的生活必需品，而網路的品質更是使用者在意的重點。 近年來由3GPP推行的LTE架構，已經在世界各地如北美、南韓、日本鋪設，新一代可連接LTE的3C產品更已開始量產銷售，可以看出LTE已成為新一代行動通訊技術的主導者。 儘管LTE在通訊架構與天線技術上有所進展，但在終端設備與基地台上仍需要大量時間做資料處理。對於TCP使用者來說，不僅增加了RTT同時也減少了傳輸速率，是使用者不樂於見到的。 關於這點，我們提出了一個以原架構為基礎的辦法，試圖減去LTE中的HARQ所帶來的RTT，藉以增加傳輸速率。研究成果也顯示了新架構在特定環境下，對於傳輸速率是有益處的。

As the progress of technology, with rapid substitution of smart phone and pad devices, the role of mobile communication network almost equals to the cable network, and becomes necessary in citizen’s daily life. The network quality is the factor that users care about mostly. In recent years, LTE telecommunication system propelled by 3GPP is spread over North America, South Korea and Japan, and the new generations of 3C products are also equipped with LTE chips. We can know that LTE has become the leader of new telecommunication technology. Although LTE has made progress in communication architecture and antenna technology, it still needs time to process data in terminal devices and base stations. For TCP data user, the processing time not only increases TCP RTT but also decreases transmission throughput, which users don’t expect for. For this point, we propose an idea based on the original architecture, trying to eliminate the RTT brought by HARQ in LTE for increasing transmission throughput. The research results do show that in some constraint environments, the idea has benefits on transmission throughput.