【正文】 基于 matlab 的信道編碼仿真 1 海 南 大 學 畢 業(yè) 論 文（設計） 題 目： 基于 matlab 的信道編碼仿真 學 號： 姓 名： 年 級： 學 院： 信息科學技術學院 系 別： 電子信息工程 專 業(yè)： 電子信息工程 指導教師： 完成日期： 基于 matlab 的信道編碼仿真 1 摘 要 通 信技術的飛速發(fā)展，信道編碼已經成功地應用于各種通信系統(tǒng)中。以及各種傳輸方式對可靠性要求的不斷提高，信道編碼技術作為抗干擾技術的一種重要的手段，在數(shù)字通信技術領域和數(shù)字傳輸系統(tǒng)中顯示出越來越重要的作用。 信道編碼的目的是為了改善通信系統(tǒng)的傳輸質量。由于實際信道存在噪聲和干擾，使發(fā)送的碼字與信道傳輸后所接收的碼字之間存在差異，稱這種差異為差錯。一般情況下，信道噪聲、干擾越大，碼字產生差錯的概率也就越大。 本文利 用 matlab 對二進制對稱信道 (BSC)，高斯白噪聲信道 (AWGN)兩種信道的仿真， （ 7,4） Hamming 碼對信道的仿真，通過誤碼率的曲線圖來了解信道的編碼。并利用 matlab 的 simulink 模塊仿真，運用 simulink 里的卷積碼 viterbi 譯碼器來對二進制對稱信道和高斯白噪聲信道的仿真，觀察誤碼率的曲線圖來了解 2 個信道的不同。 關鍵字 ： matlab，信道，編碼，譯碼， Simulink。 基于 matlab 的信道編碼仿真 2 Abstract With the rapid development of munication technology, channel coding has been successfully applied to various munications systems. And a variety of transmission of the continuous improvement of reliability requirements, antijamming channel coding technology as an important means of technology in the field of digital munications technology and digital transmission systems in a more and more important role. The purpose of channel coding is to improve the transmission quality of munications systems. As the actual existence of the channel noise and interference, the transmitted codewords and channel transmission received after the difference between code words, said this difference is wrong. Under normal circumstances, channel noise, the greater the interference, the code word generated the greater the probability of error. In this paper, matlab binary symmetric channel (BSC), Gaussian white noise channel (AWGN) two channel simulation, (7,4) Hamming code simulation of the channel, through the bit error rate curve to understand the channel coding. Using matlab to simulink block simulation, using simulink in the viterbi decoder to convolutional codes on the binary symmetric channel and Gaussian white noise channel simulation, observation error rate graphs to understand the two different channels Keywords: matlab, channel, coding, decoding, Simulink. 基于 matlab 的信道編碼仿真 3 目錄 1 引言 .................................................................................................................................... 1 選題的目的和意義 ......................................................................................................... 1 本選題的理論依據(jù)、研究內容 ..................................................................................... 1 MATLAB 的介紹 ..................................................................... 2 信道編碼的概念及分類 ................................................................................................ 2 信道編碼定理及信道編碼中所包含的各種碼類的簡介 ............................................ 2 卷積碼 .......................................................................................................................... 2 線性分組碼 .................................................................................................................. 3 循環(huán)碼 .......................................................................................................................... 3 MATLAB 語言的簡介 ....................................................................................................... 4 Simulink ........................................................................................................................... 5 .................................................................................................................................... 5 二進制對稱信道（ BSC） ............................................................................................... 5 二進制刪除信道（ BEC） ............................................................................................... 6 高斯白噪聲信道 (AWGN) ................................................................................................ 6 4. Hamming 碼 ....................................................................................................................... 7 漢明碼 ............................................................................................................................. 7 校驗方法 ......................................................................................................................... 7 漢明碼編碼 ..................................................................................................................... 9 漢明碼對高斯白噪聲 信道 .......................................................................................... 9 漢明碼對二進制對稱信道的仿真 ............................................................................ 11 .............................................................................................................................. 15 卷積碼定義與原理 ....................................................................................................... 15 維特比譯碼原理 ........................................................................................................... 15 卷積碼譯碼器對高斯白噪聲信道的設計與仿真 ....................................................... 18 卷積碼譯碼器的設計與仿真 .................................................................................... 19 基于 matlab 的信道編碼仿真 4 簡化維特比譯碼器的仿真 ........................................................................................ 22 卷積碼譯碼器的誤碼率分析 .................................................................................... 24 卷積編碼器在二進制對稱信道（ BSC）中的性能 ..................................................... 25 .................................. 30 .................................................................................................................................. 31 致謝 .................................................