在本論文中，我們 針對具有任意 針對具有任意 用戶數且採正交相移鍵控 用戶數且採正交相移鍵控 用戶數且採正交相移鍵控 (QPSK)調變的下行多 輸入多出 非正交多重接取 (MIMO-NOMA)系統，進行深入的位元錯誤率（ 系統，進行深入的位元錯誤率（ 系統，進行深入的位元錯誤率（ 系統，進行深入的位元錯誤率（ 系統，進行深入的位元錯誤率（ 系統，進行深入的位元錯誤率（ BER）效能 分析 ；我們 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 的分析別針對完美與不通道狀態資訊情境，且 同時考 量 MIMO-NOMA傳輸所造成的多重接取干擾、 傳輸所造成的多重接取干擾、 連續干擾消除 所產生的錯誤傳播 、傳輸 /接收天線 間的空相關性等因素影響 。首先， 首先， 在使用 傳統 格雷 編碼 的情況下，我們推導出單輸 的情況下，我們推導出單輸 的情況下，我們推導出單輸 入單輸出 (SISO) NOMA系統中個別用戶的一般 系統中個別用戶的一般 BER表示式，然後將之擴展至 表示式，然後將之擴展至 表示式，然後將之擴展至 MIMO情境，其中 情境，其中 情境，其中 每個數據流 可視為 包含多重接取干擾和 連續干擾消除 效應的一條 SISO鏈路； 鏈路； 基於 類似 的分析方法 ，我們進一步推導出在使用 聯合 格雷 編碼 情況 下之 MIMO-NOMA系統 的 BER表示式。電腦模擬 式。電腦模擬 式。電腦模擬 結果 證實 ，所 推導出的 BER表示式在各種考量的情況下 都具有 高度準確性 ，而 通道相關性和估 測誤差 則會導致明顯的 BER效能衰退 。

In this thesis, we perform a comprehensive analysis of the bit-error-rate (BER) performance for a downlink multiple-input multiple-output non-orthogonal multiple access (MIMO-NOMA) system with an arbitrary number of users and quadrature phase shift keying modulation. The multiple access interference (MAI) from MIMO-NOMA transmission, error propagation due to successive interference cancellation (SIC), and spatial correlation among transmit/receive antennas are considered under both perfect and imperfect channel state information scenarios. Initially, general BER expressions are derived for individual users in a single-input single-output (SISO) NOMA system with conventional Gray coding (GC). These are then extended to a MIMO scenario with conventional GC by treating each data stream as a separate SISO link with additional MAI and SIC effects. Similar BER expressions are further derived for a MIMO-NOMA system with joint GC. Extensive computer simulations demonstrate that the derived BER expressions have high accuracy for various considered cases. It is also observed that both channel correlation and channel estimation errors would cause a significant degradation on the BER performance.

Abstract
Contents
List of Figures
List of Tables
I. Introduction 1
II. System Model 4
A. Channel Model 4
B. Signal Model 5
III. BER Analysis for SISO-NOMA Systems under Conventional Gray Coding 8
A. BER Expressions for a Three-User SISO-NOMA System under Perfect CSI 8
B. BER Expressions for a SISO-NOMA System with an Arbitrary Number of Users under Perfect CSI 12
C. BER Expressions for a SISO-NOMA System with an Arbitrary Number of Users under Imperfect CSI 13
IV. BER Analysis for MIMO-NOMA Systems under Conventional Gray Coding 15
V. BER Analysis for SISO/MIMO-NOMA Systems under Joint Gray Coding 19
VI. Simulation Results 21
A. Simulation Arrangements 21
B. Validation of the Analytical BER Expressions 22
C. Impacts of Channel Correlation and Channel Estimation Errors 22
VII. Conclusions 33
References 34

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