在本論文中，我們針對非完美通道資訊情境探討適用於下行多輸入多輸出
( 非正交多重接取 ( 系統的 預編碼器和解碼器設計問題，此系統包
含 一個基地台和兩個 使用者。 首先，我們設置 一個 初始預編碼 矩陣並 求出一個最
佳功率分配係數以最小化所有解碼過程 的 最大 均方誤差；然後，針對兩個使用者
分別設計解碼器以最小化各自解碼訊號的均方誤差；接著，在固定傳輸功率的條
件下， 以 最小化 兩個 使用者 的解碼訊號之均方誤差總和 為設計準則， 更新預編碼
器 ；上述過 程可經由迭代方式重複多次以進一步改善效能。電腦 模擬結果 顯示
在 合理的 通道估測誤差情境下， 所提 出的 聯合預編碼器和解碼器設計 方法 皆 有良
好的效 能表現。

In this
thesis , we investigate precoder and decoder designs for a downlink multiple
input multiple output (MIMO) non o rthogona l multiple access (NOMA) system with a
base station an d two users under a scenario of imperfect channel sta te information. A n
initial precoding matrix is set and an optimal power allocation factor is calculated to
minimize the maximum mean squared error (MSE) for all the decoding processes. Then,
t he corresponding decoders are designed for t he two users to minimize the MSE of the
decoded signals for each decoder Subsequently, the precoder is updated by formulating
an optimization problem to minimiz e the sum of MSEs for the two user’s decoded
signals under a transmit power constraint The above procedure can be repeated for a
specified number of iterations for further performance improvement Simulation resul ts
show that the proposed joint precoder a nd decoder design achieve s good performnace
for reasonable channel MSE scenarios.

Contents
Absrtract i
Contents ii
List of Figures iii
I.Introduction.................................................1
II.System Model................................................5
III.Proposed Precoder And Decoder Design.......................6
A.Initial Precoder Design......................................6
B.Decoder Design...............................................6
C.Precoder and Decoder with Imperfect CSI......................8
IV.Simulation Results..........................................15
V.Conclusion...................................................20
References.....................................................21

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