在第五代行動網路中，毫米波通訊透過高頻段的傳輸，能為網路系統提供更充裕的頻寬資源並提升網路容量，然而，高頻的毫米波通訊伴隨的是高路徑損耗及繞射能力低落導致長距離傳輸受到限制。近年來， 第六代行動網路的關鍵技術智能反射面正被熱烈地討論，通過使用大量低成本無源的反射元件，對訊號進行智能微調實踐可控制的反射，為毫米波訊號創建虛擬可視距的傳輸路徑。鑒於智能反射面的功能，本研究將以智能反射面的佈建問題為主軸，發展佈建策略以符合超密集網路之高速傳輸需求，並進一步地探討網路容量以及佈建成本，驗證佈建策略的有效性，奠定未來智能反射面佈建情境之基礎。基於智能反射面無源反射之特性，反射過程將會面臨兩段路徑損耗，為此，本論文採取近使用者端的佈建方法，縮短智能反射面與使用者之間的反射路徑長度，此外，更考量佈建位置的分佈以縮短基地台與智能反射面的傳輸距離，避免整體疊加的路徑損耗過大，影響訊號品質，同時，為減少智能反射面之反射面向導致服務人數下降的可能，佈建過程同時調整反射面向以提升單位成本貢獻的效能。實驗結果顯示，本論文提出的環式權重支配演算法能佈建出較好的反射路徑，與其他佈建演算法相比，可提升20.5%的平均可達率以及20.2%的網路容量，有效地提升行動網路的通訊品質。

In the fifth-generation (5G) mobile networks, millimeter wave (mmWave) communication provides sufficient bandwidth resources for the network system and enhances network capacity by operating on high-frequency bands. However, mmWave communication with high-frequency band results in severer path loss and worse diffraction capability that restricted to short-distance transmission. In recent years, a novel technology called intelligent reflecting surface (IRS) has emerged in sixth-generation (6G) wireless communications. By incorporating with multitudes of low-cost passive reflective metasurfaces, IRS enables precise signal manipulation through controllable reflection, thereby establishes virtual line-of-sight paths for mmWave signal. The focus of this thesis is the deployment problem and strategy of IRS to tally with the high-speed transmission requirement of ultra-dense networks. Then, the thesis further investigates network capacity and deployment cost to validate the proposed deployment strategy and algorithm. Based on the passive reflection characteristic of IRS, the communication path suffers from two cascading path losses. Therefore, the thesis adopts the user-side deployment method to minimize the distance between IRS and user for mitigating one of unavoidable path losses. The distribution of deployment locations is also considered to minimize the distance between macrocell and IRS for avoiding excessive cascading path losses. In addition, the proposed deployment algorithm considers the orientation of IRS to serve more users with high cost-efficiency. Experimental results showed that the proposed Ring-weight Dominating algorithm establishes better reflection paths. Compared to other algorithms, it improves 20.5% achievable rate and increases 20.2% network capacity. In conclusion, the deployment strategy and proposed algorithm improves communication quality effectively.

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