Receiver Design in Downlink MC-CDMA Communication System with Antenna Array 陳樵榕、武維疆
E-mail: [email protected]
ABSTRACT
In this paper, we exploit transmit diversity in downlink multicarrier CDMA (MC-CDMA) system to provide a receiving scheme. Our first emphasis is on designing a blind (without knowing the undesired users’ signatures) MC-CDMA receiver in the mobile station that can suppress the multiple access interference (MAI) and combine the desired signal stemmed from all the transmitting antennas.
Three blind receivers are proposed in this paper. The first one is the conventional single-user matched filter (MF) receiver and the second one is designed to meet the minimum-output-energy (MOE) criterion. Since both receivers premise on accurate knowledge of the vector channel impulse responses (VCIR), hence we develop a subspace-based blind (without requiring training sequences) algorithm to estimate the VCIR of downlink antenna array MC-CDMA system. The third receiver is referred to as the
Decorrelating-RAKE (D-RAKE) receiver which is designed without knowing the desired users channel parameters. Furthermore, we present a spreading codes selection rule that enables the simple MF receiver to achieve the performance of the MOE and optimum linear receiver. Simulation results demonstrate not only the significant gain by employing the proposed codes selection rule but also the MAI resistant.
Keywords : Multicarrier CDMA (MC-CDMA), Matched filter (MF), Minimum-Output-Energy (MOE), Vector channel impulse responses (VCIR), Subspace, Decorrelating-RAKE (D-RAKE)
Table of Contents
封面內頁 簽名頁 授權書．．．．．．．．．．．．．．．．．．．．．．．．．．．．iii 中文摘要．．．．．．．．．
．．．．．．．．．．．．．．．．．．iv 英文摘要．．．．．．．．．．．．．．．．．．．．．．．．．．．v 誌謝
．．．．．．．．．．．．．．．．．．．．．．．．．．．．．vi 目錄．．．．．．．．．．．．．．．．．．．．．
．．．．．．．．vii 圖目錄．．．．．．．．．．．．．．．．．．．．．．．．．．．．ix 第一章 緒論．．．．．．
．．．．．．．．．．．．．．．．．．．．1 1.1 研究動機．．．．．．．．．．．．．．．．．．．．．．．．．．1 1.2 研究方法．．．．．．．．．．．．．．．．．．．．．．．．．．2 1.3 內容大綱．．．．．．．．．．．．．．．
．．．．．．．．．．．3 第二章 MC-CDMA系統．．．．．．．．．．．．．．．．．．．．．．4 2.1 MC-CDMA基 本架構．．．．．．．．．．．．．．．．．．．．．．4 2.2 MC-CDMA接收信號模型．．．．．．．．．．．．．．
．．．．．．9 2.3 耙式接收器(Rake receiver)．．．．．．．．．．．．．．．．12 2.4 解相關檢測器(Decorrelating Detector)．．．．．．．．．．15 2.5 信號處理技術．．．．．．．．．．．．．．．．．．．．．．．．18 2.5.1 MPDR 演算法．．．．．．．．．．．．．．．．．．．．．18 2.5.2 MUSIC演算法．．．．．．．．．．．．．．．．．．．
．20 第三章 下鏈MC-CDMA系統之盲蔽式接收器設計．．．．．．．．．．．23 3.1 信號模型．．．．．．．．．．．
．．．．．．．．．．．．．．23 3.2 盲蔽式接收器設計．．．．．．．．．．．．．．．．．．．．．28 3.2.1
Matched-filter (MF)接收器．．．．．．．．．．．．．．29 3.2.2 Minimum-Output-Energy (MOE)接收器．．．．．．．．
．30 3.3 在MC-CDMA系統中最佳碼選擇定．．．．．．．．．．．．．．．33 3.3.1原理一．．．．．．．．．．．．
．．．．．．．．．．．33 3.3.2原理二．．．．．．．．．．．．．．．．．．．．．．．40 3.3.3 Optimum(OPT)接收 器．．．．．．．．．．．．．．．．41 3.4 通道估計．．．．．．．．．．．．．．．．．．．．．．．．．41 3.5 實 際情況．．．．．．．．．．．．．．．．．．．．．．．．．45 3.6 數值分析與效能評估．．．．．．．．．．．．．
．．．．．．．47 3.6.1 數值設定．．．．．．．．．．．．．．．．．．．．．．47 3.6.2 數值分析結果．．．．．．．
．．．．．．．．．．．．．48 附錄A．．．．．．．．．．．．．．．．．．．．．．．．．．．．．58 第四章 下鏈 多MC-CDMA系統之D-RAKE接收器設計．．．．．．．．．60 4.1 Decorrelating-RAKE(D-RAKE)接收器架構．．．．．
．．．．60 4.2 實際情況．．．．．．．．．．．．．．．．．．．．．．．．．66 4.3 數值分析與效能評估．．．．．
．．．．．．．．．．．．．．．67 4.3.1 數值設定．．．．．．．．．．．．．．．．．67 4.3.2 數值分析結果．．．．
．．．．．．．．．．．67 附錄B．．．．．．．．．．．．．．．．．．．．．．．．．．．．．77 第五章結論．．．
．．．．．．．．．．．．．．．．．．．．．．．80 參考文獻．．．．．．．．．．．．．．．．．．．．．．．．．
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