在室內終端設備與物聯網（IoT）的應用場景中，除了追求高資訊傳輸率外，如何提供足夠的電力以維持設備持續運作，亦是近年來的核心課題。在傳統的射頻（RF）無線通訊系統中，頻譜擁擠與電磁干擾問題日益嚴重，使得科學家開始將目光轉向可見光通訊（VLC）系統。VLC 技術不僅能運作於廣闊的免授權頻譜，還具備抗電磁干擾的特性，因而被視為兼具前景的解決方案。
為了兼顧設備的通訊與供電需求，現已有諸多研究指出，在 VLC 系統中導入同時光波資訊與能量傳輸（SLIPT）技術能取得優異的表現。然而，目前多數文獻過於聚焦在最小化系統的能量消耗，我們認為在特定場景下，過度壓低能耗將會大幅犧牲系統的資訊傳輸率。因此，本文轉而以能同時兼顧資訊傳輸率與能量消耗的能量效率（Energy Efficiency）作為優化目標。
本文在基於 SLIPT 的可見光通訊架構下，進一步結合了光學智慧反射面（OIRS）與非正交多重進接（NOMA）技術。我們以滿足終端設備的最低電力需求與最低訊號傳輸率為約束條件，提出了一個基於區塊座標下降（BCD）的優化演算法。針對該系統模型的非凸（Non-convex）優化難題，我們將其拆解為發射功率分配以及OIRS分配兩個子問題，並透過疊代演算法尋求最佳解。

In indoor environments and Internet of Things (IoT) applications, keeping devices running with enough power is a key challenge, along with getting high data rates. In traditional radio frequency (RF) wireless systems, spectrum crowding and signal interference are getting worse. This has made researchers look into visible light communication (VLC) systems. VLC uses a large, free spectrum and does not suffer from radio interference, making it a very promising solution.
To meet both communication and power needs, many studies show that putting simultaneous lightwave information and power transfer (SLIPT) into VLC systems works very well. However, most existing papers focus too much on cutting down system energy use. We believe that in some cases, pushing energy use too low will restrict the data rate. Therefore, this paper focuses on maximizing energy efficiency, which balances both data rate and energy consumption.
Specifically, we bring optical intelligent reflecting surfaces (OIRS) and non-orthogonal multiple access (NOMA) technologies into a SLIPT-based VLC setup. Under the constraints of the devices' minimum power and data rate needs, we set up an optimization problem and propose a Block Coordinate Descent (BCD)-based algorithm. To solve this difficult non-convex problem, we break the original problem into two simpler subproblems—power allocation and OIRS allocation—and solve them step by step until the results converges.

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