【正文】 WLAN)、數(shù)字音 /視頻廣播 (DAB/DVB)等系統(tǒng)中，并很有可能成為第四代移動通信的核心技術(shù)。其中一個主要原因就在 于它能夠很好地對抗頻率選擇性衰落或窄帶干擾。穩(wěn)健的移動無線通信系統(tǒng)不僅要有具備克服大的路徑損耗和非常嚴重的信號衰落的能力，而且還要有抗大的多徑時延擴展所引起的符號干擾 (InterSymbol Interference， ISI)的能力。 關(guān)鍵字 ： 正交頻分復用，峰值平均功率比，部分傳輸序列， 迭代翻轉(zhuǎn)法 東北大學秦皇島分校畢業(yè)設(shè)計（論文） 第 II 頁 The Simulation of the Reduction of PAPR in OFDM system Author： Li Hui Tutor： Huang Liqun Abstract OFDM (orthogonal frequency division multiplexing) is regarded as the core technology of 4G wireless munication system in the future. It transmits information through orthogonal multiple subcarriers. It is also adaptive to highrate data transmission and multimedia data transmission. However, it has high peaktoaverage power ratio (PAPR), which is its inherent disadvantage. OFDM technique is introduced in this paper which used to produce the purpose and significance, and its development today. Focus on analysis of the current used to reduce the PAPR of OFDM signal four ways, namely, the signal predistortion technology, block coding technique, highspeed coding and matrix transformation, it also analyzes the highrate coding method, partial transmit sequence (PTS) and selective mapping (SLM) these two methods. Through its simulation and parison which has been the plexity of PTS is a high PAPR reduced OFDM system, the conclusions of the method. A method of reducing the plexity of PTSm sequence of PTS method is presented in this paper. Through the theoretical analysis and the design of MATLAB simulation of four methods to reduce the advantages and disadvantages of OFDM system, Final analysis of a proposed reduction method of PTSm plex sequence of PTS method. Simulation results show m sequence PTS method can not only reduce the plexity, but also reduce the PAPR system. Key Words: OFDM (orthogonal frequency division multiplexing), PAPR (peakaverage power ratio), partial transmit sequence, msequence 東北大學秦皇島分校畢業(yè)設(shè)計（論文） 第 III 頁 目 錄 1 緒 論 ............................................................................................................................. 1 課題背景 ..................................................................................................................... 1 OFDM 系統(tǒng)的主要優(yōu)缺點 ........................................................................................ 2 降低 OFDM 系統(tǒng)峰均比的研究現(xiàn)狀 ....................................................................... 3 本章小結(jié) ..................................................................................................................... 4 2 OFDM 系統(tǒng) 的原理及其 峰均比的定義 ............................................................................. 5 OFDM 系統(tǒng)的基本原理 ...... ......................................................................................5 峰均比（ PAPR）的定義 ........................................................................................... 8 OFDM 系統(tǒng)中 PAPR 的分布 .................................................................................... 9 本章 小結(jié) ...................................................................................................................11 3 降低 OFDM 系統(tǒng) PAPR 值 的四種方法及其仿真 ........................................................... 12 信號預畸變技術(shù) ........................................................................................................ 12 限幅方法 ............................................................................................................ 12 壓擴變換 ............................................................................................................ 13 編碼 類技術(shù) ................................................................................................................ 14 編碼效率 ............................................................................................................ 14 格雷互補序列降低 PAPR 的方法 .................................................................. 155 概率類技術(shù) ................................................................................................................ 17 矩陣變換方法 ............................................................................................................ 17 系統(tǒng)模型 ............................................................................................................ 17 變換矩陣 ............................................................................................................ 18 本章小結(jié) .................................................................................................................... 19 4 概率類技術(shù) ........................................................................................................................ 21 選擇性映射（ SLM） ................................................................................................ 21 選擇性映射簡介 ................................................................................................ 21 SLM 方法性能分析 ........................................................................................... 22 部分傳輸序列（ PTS） ............................................................................................. 23 PTS 方法原理 .................................................................................................... 23 子序列分割方法 .................................................................. 錯誤 !未定義書簽。然后分析了 OFDM 系統(tǒng)的基本原理及其關(guān)鍵技術(shù)，重點分析目前用于降低 OFDM信號 PAPR的四種方法，即信號預畸變技術(shù)、編碼類技術(shù)、概率類技術(shù)和矩陣變換法，著重分析了概率類技術(shù)中部分傳輸序列 (PTS)和選擇性映射 (SLM)這兩種方法。 涉密論文按學校規(guī)定處理。對本文的研究做出重要貢獻的個人和集體，均已在文中以明確方式標明。對本研究提供過幫助和做出過貢獻的個人或集體，均已在文中作了明確的說明并表示了謝意。盡我所知，除文中特別加以標注和致謝的地方外，不包含其他人或組織已經(jīng)發(fā)表或公布過的研究成果，也不包含我為獲得 及其它教育機構(gòu)的學位或?qū)W歷而使用過的材料。除了文中特別加以標注引用的內(nèi)容外，本論 文不包含任何其他個人或集體已經(jīng)發(fā)表或撰寫的成果作品。本人授權(quán) 大學可以將本學位論文的全部或部分內(nèi)容編入有關(guān)數(shù)據(jù)庫進行檢索，可以采用影印、縮印或掃描等復制手段保存和匯編 本學位論文。 本論文首先介紹了