前幾年因為疫情大爆發促使了物聯網設備需求大幅度成長，迫切增加支持廣泛連接並提供靈活頻譜服務的網絡結構的需求。為了滿足這一需求，研究人員在頻譜上找尋另外一種可用資源，有發展前景的可見光通訊，它可以同時提供照明以及通訊功能。可見光通訊不僅可以增加資料流的傳輸量，而且還顯著降低無線系統的功耗和相關碳足跡。本論文採用了一種在多蜂巢VLC及RF混合系統中，使用協同式非正交多重存取技術的新型傳輸框架，旨在提高整體系統的能源效率和降低中斷機率。儘管VLC提供前景廣闊的高速率數據傳輸，但位於AP覆蓋範圍邊緣的用戶仍面臨嚴重的干擾問題。因此我們提出了一種對用戶的新定義，目的在引入多個用戶間的合作，使不受干擾影響的用戶成為中繼點，協助傳送訊號至坐落在重疊區域的用戶，因為中繼點發射出的訊號是使用RF，與VLC頻代不同所以不會產生干擾，大大增進了頻譜效率。除此之外，在多蜂巢的架構下，探討選擇連接AP的問題，並考慮每個用戶的需求，進行資源分配，在傳輸功率的限制之下，盡可能地提升網路服務質量。
最後，使用ns-3.25模擬工具來模擬我們的網路環境，模擬結果顯示我們提出的兩種方法在有效能源效率、中斷機率、總資料傳輸量以及執行時間上，比起傳統非正交多重接取技術皆有所改進。

The COVID-19 pandemic has catalyzed a significant surge in IoT devices, underscoring the urgent necessity for network structures capable of supporting extensive connections and delivering flexible spectrum services. To address this need, Visible Light Communication (VLC) emerges as a promising solution, ingeniously merging illumination and communication functionalities. Not only does VLC offer the capacity for managing the increased traffic, but it also significantly reduces power consumption and the associated carbon footprint of wireless systems, further enhancing its appeal in the current context. This paper explores and assesses a novel transmission framework employing cooperative non-orthogonal multiple access (Co-NOMA) within hybrid VLC/radio-frequency (RF) systems, aiming to enhance overall system energy efficiency as well as outage probability. Although VLC offers promising high-data rate capabilities, users situated at the cell-edge grapple with significant interference issues in the multi-cell network. This work focus on a network architecture encompassing VLC Access Points (APs) and multiple strong and weak users, with a variable user distribution that redefines the notion of strong and weak users. The paper aims to optimize energy efficiency, achieved by collectively determining the pairings of strong-weak users, establishing the process of AP selection (which includes SSS and Non-Discriminative Strategy (NDS) for user to decide their respective AP), and configuring the power for each user message. All these measures adhere to constraints pertaining to user connectivity and transmission power. Subsequently, this paper proposes two methods, CQB and NCS, for pre-sorting weak users prior to initiating user pairing. These methods are compared with the Hungarian algorithm, and the results demonstrate that not only is the execution time reduced, but the overall performance is also improved. Finally, we introduce a residual power allocation under Quality of Service (QoS) consideration scheme. This strategy leads to the more effective use of network resources, resulting in enhanced overall network performance.

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