臺灣博碩士論文加值系統

在本論文中，我們探討在已知通道統計訊息情境下之非正交多重接取(non-orthogonal multiple acces；NOMA)下行系統的使用者選擇與功率分配問題，此系統包含一個基地台和多個使用者。我們首先推導出每一個NOMA使用者近似的期望通訊容量表示式，接著形成一個NOMA使用者間功率分配的最佳化問題，企圖在總功率限制和服務品質要求的條件下最大化所有NOMA使用者的期望通訊容量總和；然後提出一個最佳功率分配的閉合解，再據以發展一個具有低複雜度的使用者選擇演算法，以在連續干擾消除成功機率的限制條件下，最大化每一次NOMA傳輸的使用者個數。電腦模擬結果顯示，所提出的使用者選擇與功率分配方法在期望通訊容量總和、每一次傳輸的平均使用者個數以及平均位元錯誤率方面皆有相當優異的表現。

In this thesis, we investigate user selection and power allocation issues of a downlink non-orthogonal multiple access (NOMA) system with statistical channel state information, where a base station provides services to multiple users. An approximated expected capacity expression is first derived for each of NOMA users, and then a power allocation optimization problem among all NOMA users is formulated for maximizing the expected sum capacity under a total power constraint and a quality-of-service condition. A closed-form power allocation solution is derived and subsequently used to develop a low-complexity user selection method that can maximize the NOMA cluster size subject to a constraint in terms of the probability of successful successive interference cancellation for NOMA transmission. Computer simulation results demonstrate that the proposed user selection and power allocation scheme achieves excellent performance in terms of the expected sum capacity, the average cluster size for each transmission, and the average bit error rate.

Contents
Abstract----------i
Contents----------ii
List of Figures---iii
I. Introduction----------------------------1
II. System Model----------------------------4
III.Proposed Power Allocation Method---------------6
A. Problem Formulation----------------------------6
B. A Closed-Form Power Allocation Solution--------6
IV. Proposed User Selection Method-----------------------------11
A. An SIC Constraint------------------------------------------11
B. A User Selection Algorithm with the SIC Constraint---------13
V. Simulation Results----------18
VI. Conclusion------------------25
References----------------------26

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