國際電信聯盟(International Telecommunication Union, ITU)於2015年6月提出IMT-2020計畫，計畫中明確定義了5G的三大方向為：增強型行動寬頻通訊(Enhanced Mobile Broadband, eMBB)、大規模機器型通訊(Massive Machine Type Communications, mMTC)和超可靠度和低延遲通訊(Ultra-reliable and Low Latency Communications, URLLC)。本論文主要是針對URLLC方向中，對軟體實體層(Physical Layer, PHY)中對時間敏感之RU(Radio Unit)架構設計。
首先，針對HARQ的回傳訊號時間提出新的架構設計。因為在4G之下，當急需回傳訊號時只能等到4個subframe後才能進行回傳HARQ，此時已延遲多時。因此，藉由將每個使用者的回傳時間優先順序進行排程，依照每位使用者不同的要求為其量身訂做回傳時間，讓每位使用者都能夠擁有最好的使用者體驗。 然而，在4G LTE時，RU與L1組合僅能最多同時服務16個使用者裝置，如此數量不足以支撐5G龐大的使用者數量。因此，我們針對這個問題提出了新的RU與L1架構設計。本研究實現了5G NR軟體實體層中對時間敏感之RU架構設計，並且其滿足了URLLC的低延遲需求。

International Telecommunication Union (ITU) proposed the IMT-2020 project in June 2015. The plan clearly defines three directions of 5G: Enhanced Mobile Broadband (eMBB), large-scale Massive Machine Type Communications (mMTC), and Ultra-reliable and Low Latency Communications (URLLC). This thesis is mainly to design the Soft-PHY (software-defined Physical Layer) time-sensitive Radio Unit (RU) Architecture for the URLLC.
First, a new architecture design is proposed for HARQ's backhaul signal time. Under 4G, when it is urgent to return the signal, it can only wait for 4 subframes before returning HARQ. This will result in the delay for 5G application. Therefore, by scheduling each user's return time priority and tailoring the return time according to the different requirements of each user, each user can have the best user experience. Moreover, in 4G LTE, the combination of RU and L1 can only serve up to 16 user devices at the same time, so the number is not enough to support the huge number of 5G users. Therefore, we propose a new RU and L1 architecture design for this problem. This study physically implements the Soft-PHY time-sensitive RU architecture for the URLLC and it satisfies the requirement of low latency for URLLC.

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