【正文】 LineWidth39。 mod=[]。title(39。隨機(jī)信源 39。④還有就是一定要仔細(xì)，仔細(xì)，再仔細(xì)。 for i=1:len if(codeout(i)~=decodeAMI(i)) errornum=errornum+1。 Dr( 1+length(t) ) = 0。title(39。 Ak=fft1.*Hk。ws=2*pi*3500。)。 figure(4) subplot(2,1,1)。 cp=[]。由 “ 0”和“ 1”表示的二進(jìn)制調(diào)制信號通過 電平 轉(zhuǎn)換后，變成由“ – 1”和“ 1”表示的雙極性 NRZ（不歸零）信號，然后與 載波 相乘，即可形成 2PSK 信號， 在 MPSK 中，最常用的是四相相移鍵控，即 QPSK（ Quadrature Phase Shift Keying），在衛(wèi)星 信道 中傳送數(shù)字電視信號時采用的就是 QPSK 調(diào)制方式。漢明碼編碼 39。 for k=1:length(yn) if xn(k) == 1 num = num + 1。)。加性噪聲：疊加在信號上的一種噪聲，通常記為 n(t)，而且無論有無信號，噪聲 n(t)都是始終存在的。但這種方法比簡單重傳協(xié)議的成本要高。 信源調(diào)制 DM 調(diào)制 對模擬信號采樣，并用每個樣值與它的預(yù)測值的差值對周期脈沖序列進(jìn)行 調(diào)制 ，簡稱 △ M 或 DM。 關(guān)鍵字： MATLAB 編碼 調(diào)制 解調(diào) 譯碼 通信系統(tǒng) 武漢理工大學(xué)《 學(xué)科基礎(chǔ)課群綜合訓(xùn)練 》 報(bào)告 II Abstract Communication is through some of the information transmission media, the purpose is to transmit information, munication system is used to plete the process of information transmission technology system body, the function is the information from the source sent to one or more of the destination. Modulation and demodulation in information transmission process plays an important role, is indispensable, so the system of modulation and demodulatio n process is extremely important. MATLAB is set numerical calculation, graphics, image processing and system simulation and powerful function in the integration of scientific puting language, its powerful matrix operation and graphics visual function and rich toolbox, as the munication system of the modulation and demodulation process analysis provides a great convenience. Modulation in a munication system has a very important role. Through the modulation, can not only move the modulation signal spectrum, and the spectrum of the move to want the position, and the modulation signal into suitable for transmission of the modulated signal, and it to the system transmission efficiency and the reliability of the transmission often determines a munication system performance. MATLAB software is widely used in digital signal analysis, system identification, time series analysis and modeling, neural works, dynamic simulation for such applications. This topic using MATLAB software simulation signal P CM coding, Manchester coding, hamming code and ASK modulation, through AWGN channel, and demodulation, decoding the integrity of the munication system simulation,. Key words： MATLAB， Coding, modulation and demodulation, decoding, munication system 武漢理工大學(xué)《 學(xué)科基礎(chǔ)課群綜合訓(xùn)練 》 報(bào)告 1 1 原理分析與方案論證 通信系統(tǒng)架構(gòu) 通信的目的是傳輸信息。 指導(dǎo)教師簽名： 2021 年 12 月 4 日 系主任（或責(zé)任教師）簽名： 2021 年 12 月 4 日 武漢理工大學(xué)《 學(xué)科基礎(chǔ)課群綜合訓(xùn)練 》 報(bào)告 目錄 摘要 ................................................................................................................................. I 1 原理分析與方案論證 ...................................................................................................1 通信系統(tǒng)架構(gòu) ...................................................................................................1 信 源調(diào)制 —— DM調(diào)制 ......................................................................................2 基帶碼 —— AMI 碼 ...........................................................................................2 AMI 碼編碼規(guī)則 .......................................................................................2 AMI 解調(diào)原理 ...........................................................................................3 信道碼 —— 漢明碼 ............................................................................................3 噪聲信道 —— AWGN.........................................................................................5 2 各模塊的 MATLAB 實(shí)現(xiàn) ..............................................................................................5 信號源的實(shí)現(xiàn) ...................................................................................................5 信源編碼 —— DM增量調(diào)制 ...............................................................................6 DM 編碼簡介 .........................................................................................6 DM 編碼的實(shí)現(xiàn) .....................................................................................6 基帶編碼 —— AMI 編碼 ....................................................................................7 信道編碼 —— 漢明碼編碼 ..................................................................................8 漢明碼編碼分析 .....................................................................................8 漢明碼的 MATLAB 實(shí)現(xiàn) ........................................................................9 PSK調(diào)制 ....................................................................