近年來，可連網裝置的數量有著爆炸性的增長。對此，窄頻物聯網（NB-IoT）系統及相關規格應運而生。本篇論文將上行窄頻物聯網系統和非正交多重接取（NOMA）系統結合，並利用一套有效的資源分配演算法，進一步提升頻譜效率和同時可服務裝置的數量。本篇論文著重在頻段內（in-band）的部署模式，並與獨立（stand-alone）模式比較。由於頻譜洩漏，除了使用同一個子載波資源的兩個裝置會互相干擾外，不同子載波內的裝置也會互相干擾。而因為頻段內模式的窄頻物聯網系統是佔用一個長期演進技術（LTE）系統的一個實體資源區塊（PRB），因此窄頻物聯網系統和長期演進技術系統的訊號也會互相干擾。本論文的演算法分為兩個部分，分別是子載波分配及傳送功率控制。將模擬結果和現存之正交多重接取（OMA）窄頻物聯網系統比較，顯示窄頻物聯網系統在結合非正交多重接取系統後，頻譜效率有顯著的提升。

In recent years, there is a rapid increase in the number of network-connectable devices. In this regard, Narrowband Interference of Things (NB-IoT) systems and their specifications are developed. For improving the spectral efficiency and servicing more devices, we combine uplink NB-IoT systems and Non-Orthogonal Multiple Access (NOMA) systems with efficient resource allocation algorithms. In this thesis, we focus on the systems deployed as the in-band mode, then compare the results with the stand-alone mode. Due to spectral leakage, besides the mutual interference between two devices using the same subcarrier, the interference among different subcarriers exists as well. Furthermore, the signals from NB-IoT systems and Long-Term Evolution (LTE) systems would interfere to each other since NB-IoT systems occupy one LTE physical resource block (PRB) in the in-band mode. Our algorithm in this thesis contains two parts. The first part is to allocate subcarriers to UEs with maximum transmit power. The power control in the second part is implemented according to the subcarrier allocation result from the first part. Simulation results by comparison to the Orthogonal Multiple Access (OMA) NB-IoT systems show that the spectral efficiency is improved significantly in the proposed uplink NOMA NB-IoT systems.

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