近年來，因為混合型陣列設計有減少成本昂貴的射頻元件的優點，因此在巨量多輸出多輸入系統中越來越受到重視。混合型陣列是由數個類比子陣列、類比數位轉換鏈和數位類比轉換鏈所構成，所以，混合型陣列的設計主要在最佳化類比陣列和數位陣列。然而，因為最佳化問題不是凸函數的型式，導致此問題難以解決。因此在本篇論文中，我們提出了兩個設計混合型陣列的方法，利用投影的概念設計混合型陣列搭配粒子群聚演算法解出本地解。為了完成最佳化之目標式，我們採用最小均方機制來設計最佳的類比和數位子陣列。由於最佳化式子並非凸函數，我們針對投影的目標物提出利用疊帶的方式，交替地最佳化數位以及類比子陣列。接著，我們提出最大化投影量的目標式搭配粒子群聚演算法取代最小均方誤差的目標式來得到類比子陣列，數位子陣列也就能透過偽逆矩陣得到。最後，有數個結果可以印證提出方法的效能，並且證明提出的方法比前人的方法還要優越。

Hybrid array designs have recently gotten much attention in massive multiple-input multiple-output (MIMO) systems due to alleviation of the burden of radio frequency chains and reduction of implementation cost. The hybrid arrays are constructed by several analog sub-arrays connecting to few A/D or D/A chains. Therefore, the hybrid array design aims at optimizing a composite array containing both the analog and digital arrays. However, the problem is difficult to solve due to non-convex formulation. In this thesis, we proposed two hybrid array schemes, the hybrid array with direct projection and the hybrid array via particle swam optimization, to search the local minimum solution. For the former method, we adopt the LS criterion to jointly optimize the analog and digital sub-arrays. Owing to the non-convex formulation, we then propose an alternating optimization to optimize the digital and analog sub-arrays with the proposed projection iteratively. For the later method, instead of using LS criterion, we propose utilizing maximum projection criterion with particle swam optimization to design the analog sub-array. The digital subarray can then be obtained directly with pseudo inverse. Numeral results show that the effectiveness of the proposed design and the superiority over the existing methods.

論文審定書………………………………………………………………..……………i
中文摘要………………………………………………………………..……………….ii
英文摘要……………………………………………………………………...………...iii
目錄……………………………………………………………….…………………….iv
圖次……………………………………………………………….……………………..v
第1章 導論……………………………………………………………………………..1
第2章 系統模型………………………………………………………..…………........9
第2.1節 混合型陣列天線模型……………………………………………………9
第3章 最佳全數位預編碼設計………………………………………………………14
第3.1節 最佳化問題描述………………………………………………………….14
第4章 混合型預編碼設計……………………………………………………………20
第4.1節 Nelder Mead Simplex逐個元素演算法之設計……………………….24
第4.2節 利用分子粒群演算法投影設計………………………………………….34
第4.3節 低複雜度之設計………………………………………………………….37
第5章 系統模擬及探討………………………………………………………………38
第6章 結論與未來展望………………………………………………………………45
參考文獻……………………………………………………………………………….46
附錄A…………………………………………………………………………………..49
附錄B…………………………………………………………………………………..51

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