在現行標準中的領航信號有著較緩慢衰落的頻譜旁波衰落速度，進而使得鄰近的通道產生干擾，對此有些文章提出相對應的解決方法，來讓領航信號具有快速旁波衰減的特性，然而這些方法會受限於一些條件而使得應用範圍不廣泛，像是旁波衰減速度會受限於領航序列長度的2的因數個數，又或者是會受限於各種的系統參數。為了克服這項困難，在此篇文章中提出兩個新的設計方法，能將過去適用的情況被更加的擴展，同時又能確保兩種新方法所建構出來的領航信號，具備高頻譜緊密度與最佳通道估測的能力。

The pilot waveform that can suppress power spectral sidelobes while achieving accurate channel estimation is desirable for orthogonal frequency division multiplexing systems and standards. However, the conventional pilot waveforms either suffer large power spectral sidelobes or can suppress sidelobe power effectively only when the number of pilot subcarriers has a large positive integer power of two as a factor. To overcome the problem, two design procedures are proposed in the paper to construct spectrally compact pilot waveforms with optimal channel estimation even when the number of pilot subcarriers does not have a large positive integer power of two as a factor.

論文口試委員申請書
誌謝
中文摘要 i
英文摘要 ii
圖目錄 v
表目錄 vi
符號 vii
第一章 緒論 1
第1.1節 正交分頻多工簡介 1
第1.2節 頻域旁頻抑制技術簡介 2
第1.3節 通道估測簡介 4
第1.4節 掏頻寬效益前導與領航信號簡介 6
第1.5節 論文動機 7
第二章 信號模型與快速旁波衰減 9
第2.1節 信號模型 9
第2.2節 功率譜密度 11
第2.3節 快速旁波衰減條件 12
第2.4節 頻譜主導項次 15
第三章 高頻譜緊密度領航信號設計 17
第3.1節 概述 17
第3.2節 Generalized Cascading Construction 18
第3.2.1節 在Condition A下的設計步驟 18
第3.2.2節 在Condition B下的設計步驟 20
第3.3節 Interleaving Construction 21
第3.3.1節 在Condition A下的設計步驟 22
第3.3.2節 在Condition B下的設計步驟 22
第3.4節 高頻譜緊密度領航序列範例 23
第3.5節 快速旁波衰落之比較 25
第3.6節 多階旁波衰落之條件 29
第四章 性能結果 33
第4.1節 頻譜緊密度 33
第4.2節 峰均功率比 33
第4.3節 模擬結果 34
第五章 結論 43
參考文獻 44
附錄 49

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