由於科技的蓬勃發展，未來我們對無線通訊系統的容量需求漸趨嚴苛，這使得非正交多重存取 (Non-Orthogonal Multiple Access, NOMA) 開始受到重視。NOMA技術不同於正交多從存取(Orthogonal Multiple Access, OMA)，能在同一個頻段上輸出資料給多個用戶，因此增加頻譜效率，而接收端透過連續干擾消除(Successive Interference Cancellation, SIC)的方式將訊號解回。然而連續干擾消除的方式受限於傳送端分配給不同用戶資料的功率差，因此本篇論文將探討另一種方式，在傳送端傳送訊號時將訊號透過聯合調變，使傳送的訊號符合格雷映射(Gray Mapping)，在接收端採用聯合偵測(Joint Detection)的方式解回訊號，最後在比較兩種方法的差異。;Due to the rapid development of technology, the capacity demand for wireless communication systems is becoming more and more important in the future. Therefore ,Non-Orthogonal Multiple Access (NOMA) begin to receive attention. Compared with orthogonal multi-slave access(OMA), NOMA technology can output data to multiple users in the same frequency band, thus increasing spectral efficiency. And the receiver decodes the signal by Successive Interference Cancellation(SIC). However, the way of Successive Interference Cancellation is limited by the power difference allocated by the transmitter to different user’s data. Therefore, this paper will introduce another way to transmit the signal through the joint modulation, so that the transmitted signal conforms to Gray Mapping. And the Joint Detection is used at the receivr to decode signal. Finally, compare the differences between the two methods.
