由於非正交多重接取系統(NOMA)日益重要，本論文針對該系統在不同環境下進行效能分析，而此系統為多輸入多輸出系統，其中，假設接收端的基地台則有N根天線，而傳送端的2N位使用者則各只有一根發射天線。本論文主要利用兩種不同的波束成形矩陣來分析在完美與非完美通道訊息估測下的性能，分別為強制歸零波束技術(ZF)和最小均方誤差波束技術(MMSE)。本論文將先計算不同環境下訊號與干擾加雜訊比(SINR)，接著再探討其效能。其中，完美的連續干擾消除(SIC)可實現在完美通道狀態訊息(CSI)的情況下，但若存在通道估測誤差則無法實現。而效能的探討將會以模擬圖進行比較，比較結果顯示，在上行NOMA系統中MMSE波束技術相對於ZF波束技術，在不完美的通道狀態資訊情況下可以提供較好的系統容量(Capacity)和錯誤率(BER)。

This paper analyzes the performance of Non-orthogonal multiple access (NOMA) in the presence of channel estimation error for an uplink Multiple Input Multiple Output (MIMO) system with N antennas at base station (BS) and one transmit antenna per 2N users. We investigate the performance of perfect and imperfect channel estimation by utilizing two different beamforming weight matrices methods, which are zero-forcing (ZF) and minimum mean square error (MMSE). In each situation, the calculation of capacity is derived from the signal to interference plus noise ratio (SINR), and then we examine the performance through those data. Furthermore, the perfect successive interference cancellation (SIC) can be utilized when the channel state information (CSI) is perfect, but it cannot be achieved in the presence of channel estimation error. By comparing the performance of simulation results, we notice that without perfect CSI, the MMSE beamforming is a better choice in the uplink NOMA system since MMSE offers better sum capacity and bit error rate.

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