交織分址接入技術是第四代行動通信系統的新技術方案，其基礎在於分碼多工(Code Division Multiple Access, CDMA)系統上，在交織分址接入(Interleave Division Multiple Access, IDMA)系統中，不同用户的訊號是通過不同的交織器(Interleaver)來區分。IDMA作為一種寬頻的技術，不僅繼承了CDMA的許多特性，如：CDMA中的抵抗衰減效益和降低其他用户間的干擾，而且系統複雜度低。正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)傳輸技術是通過互相正交的多載波傳輸信息，加入護衛區間(Guard Interval, GI)的放置，能够有效地對抗符元間干擾(Inter-Symbol Interference, ISI)，提高系统容量，因此我們將IDMA與OFDM技術互相结合，並且為了使該系統更加接近於分址接入的通道系統容量，結合了低密度同位檢查碼(Low Density Parity Check code, LDPC)當作編碼，架構出新的系統模型，在接收端利用多重用戶遞迴偵測(Iterative Multi-User Detection, IMUD)方式有效的消除多重用戶間的干擾，所提出的架構可以讓大量用戶在高效能下同步傳輸，並且高效能可以維持在多重路徑的環境下。

Recently, a novel technique for multi-user spread-spectrum mobile systems, the called interleave-division multiple-access (IDMA) scheme, was proposed by L. Ping etc. The advantage of IDMA is that it inherits many special features from code-division multiple-access (CDMA) such as diversity against fading and mitigation of the other-cell user interference. Moreover, it’s capable of employing a very simple chip-by-chip iterative multi-user detection strategy. In this thesis, we investigate the performance of combining IDMA and orthogonal frequency-division multiplexing (OFDM) scheme. In order to improve the bit error rate performance, we applied low-density parity-check (LDPC) coding to the proposed scheme, named by LDPC Coded OFDM-IDMA Systems. Based on the aid of iterative multi-user detection algorithm, the multiple-access interference (MAI) and inter-symbol interference (ISI) could be canceling efficiently. In short, the proposed scheme provides an efficient solution to high-rate multiuser communications over multipath fading channels.

第一章　導論................................................................................................................1
1.1 背景與研究動機............................................................................................1
1.2 論文架構........................................................................................................2
第二章 系統模型........................................................................................................4
2.0 引言................................................................................................................4
2.1 正交分頻多工系統........................................................................................4
2.2 低密度同位檢查碼…....................................................................................7
第三章 交織分址接入系統......................................................................................12
3.0 引言..............................................................................................................12
3.1 傳送端架構..................................................................................................12
3.2 接收端架構…..............................................................................................14
3.3 多重路徑衰減通道下接收端架構…..........................................................17
第四章 提出的系統架構..........................................................................................19
4.0 引言..............................................................................................................19
4.1 傳送端架構..................................................................................................20
4.2 接收端架構…..............................................................................................22
第五章 提出的系統架構下加入載波頻率誤差之探討..........................................27
5.0 引言..............................................................................................................27
5.1 已知接收端各用戶之載波頻率誤差..........................................................27
5.2 應用自身干擾消除於提出的架構中..........................................................30
第六章 效能模擬分析..............................................................................................34
第七章 結論..............................................................................................................42
中英對照表..................................................................................................................43
全名縮寫對照表..........................................................................................................46
參考文獻......................................................................................................................48

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