隨著室內無線通訊設備日益增加，傳統射頻波段逐漸不敷使用，於是研究人員將目光轉向可見光，而發展出可見光通訊 (VLC)。可見光通訊有著比射頻網路 (RF) 更大的頻寬，且頻段是不需驗證，任何人皆可使用。由於可見光不可穿透物體的特性，可見光網路有著更高的安全性，但同時也意味著可見光容易使得被物體遮擋而導致連線中斷，且相比於射頻網路的可傳輸範圍的數十、數百公尺，可見光網路的傳輸範圍僅為數公尺，因此傳輸範圍以及容易被遮擋為目前需克服的議題。智慧反射平面用於射頻網路是為了增強波束成形，使訊號可以更好的集中，而應用在可見光通訊，則是可以透過可控的被動反射元件，來調整傳送端與接收端的通道狀況，即使傳送端與接收端之前有障礙物阻擋，也能透過智慧反射平面建立通道。
功率分配在使用非正交多重存取技術下是一個重要的議題，需要遵循著此多重存取下的要求，並同時取得更好的效能。然而，目前多數的研究都以系統的角度去考量，甚少研究會考量環境中使用者的需求，提升系統效益的背後，是用戶之間的資源分配不均，使得用戶的網路速率之間落差甚大。本文在基於用戶對於無線網路環境下的不同網路速率需求，設計了功率分配方法，以最大化滿足網路速率需求的用戶人數，並在此前提下，考量用戶對於網路的需求，設計智慧反射平面元件的分配方法，改善各個用戶的通道條件，儘管是通道條件比較差的用戶，也有機會與有著較好通道條件的用戶競爭資源。

As the number of indoor wireless communication devices continues to increase, the traditional radio frequency (RF) spectrum is gradually becoming insufficient. Researchers have turned their attention to visible light, leading to the development of visible light communication (VLC). VLC offers a much larger bandwidth compared to RF networks, and this bandwidth is license-free, allowing anyone to use it. Due to the fact that visible light cannot penetrate objects, VLC provides higher security. However, this also means that visible light is blocked by objects easily, causing connection interruptions. Additionally, unlike the hundreds of meters transmission range of RF networks, the transmission range of VLC is only a few meters. Therefore, limited transmission range and susceptibility to obstruction are current challenges. Intelligent reflecting surfaces (IRS) are used in RF networks to enhance beamforming, concentrating the signal more effectively. When applied to VLC, controllable passive reflecting elements can adjust the channel conditions between the transmitter and receiver, allowing the establishment of a channel even if there are obstacles between them.
Power allocation is a crucial issue under the adoption of non-orthogonal multiple access (NOMA) technology, following this multiple access principle while achieving better performance. However, most current research focuses on the system perspective, with little consideration given to the needs of users within the environment. The improvement in system efficiency often comes at the expense of uneven resource allocation among users, resulting in significant disparities in network speeds. This thesis designs a power allocation method based on users’ different data rate requirements in a wireless network environment, aiming at maximizing the number of users whose data rate requirements are satisfied. Under this premise, it considers the users’ rate requirements and designs an IRS assignment method to improve the channel conditions for each user. Even users with relatively poor channel conditions have the opportunity to compete for resources with those having better channel conditions.

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