通信原理課程設(shè)計(jì)報(bào)告2(1)

1、in 26 cases, long-term measures to implement the rate is 77% deployed 40 couples free pre-pregnancy health checks. -Balanced development of education. I attach great importance to control fits and starts work, to ensure that school-age children to school on time, hope dream poor students go to schoo

2、l to help poor students, help students complete nine years of compulsory education. Township school-age children enrollment rate up to 100%. -Home to poverty alleviation work in order. Complete the rural minimum living standard security system and the effective connection between pro-poor developmen

3、t policies, establish the Township poor electronic records and paper file documentation work, and cooperate with the superior unit holders, such as the statistical work of the poor masses. As of now, I enjoy the low 94 families, a total of 305, 44310 rural minimum living standard security issued org

4、anization 7 operational training full-time staff with disabilities participated in the County Federation organized 15 disabled people to participate in free training in farming skills; organization of 14 patients with cataract receiving free checks, participate in the examination will now undergo su

5、rgery had been successful. -Waste management policy in place. Seriously implement the subsidy policies such as direct subsidies for grain, returning farmland to forests this year agriculture agricultural policy subsidies total 554940, of which: farmers direct subsidies for grain 389880; reforestatio

6、n subsidies 165060. -Comprehensive management of public security work steadily. Full implementation of the measures for comprehensive management of social security, increasing crackdown on all illegal and criminal activities. As of now, my alarm 30 received, 7 all kinds of disputes, mediation succes

7、sfully 6; State criminal case 3, case 7, has been investigating the 7. -Stabilisation work of letters and calls for further strengthening. Received mass petitions from 10 successful mediation, 8, investigation 1, collective skipping appeal event does not occur. Meanwhile, further strengthen publicit

8、y and mobilization work, carried out in schools, kindergartens and surrounding environment group woven fire safety and food safety 6 times, 1 traffic safety publicity and education, legal literacy, drug pictures and materials via issuing 600 and guard against cult of special publicity activities 2 a

9、ttended by 300 people, mixture of anti-evil propaganda 70. Advancing the law of six thematic activities, through the easy way, with the film projectionist the village broadcast education 44, 3600 people returning to watch. -Further development of spiritual civilization construction work. Evening lei

10、sure time, organizations in the elderly in the rural culture of Hui Xiang Hui fitness dance square, greatly enriched the lives of the masses. Use of Arbor Day, 51 labor day, May Fourth youth day festivals, organize the education campaign for the festive, educational guide people to foster patriotism

11、, socialism, collectivism and strengthen love and loyalty to the party, firmly follow the party go . Implementation of the one gang double responsibility established number one responsibility, team member management works. Five are team building. Open-minded, innovative ways to meet the actual needs

12、 of target, combining education and political education in party lecture, unified planning, unified plan, take active measures to enhance cadres quality and ability. (B) a solid foundation steadily promoting the construction of通信原理課程設(shè)計(jì)報(bào)告專 業(yè)： 通信工程2009級 班 級： 學(xué) 號： 姓 名： 指導(dǎo)教師： 王玲 陳黎霞 二012年 06月30 日目 錄1.課程

13、設(shè)計(jì)的目的和作用12.課程設(shè)計(jì)題目內(nèi)容和要求13.課程設(shè)計(jì)的基本原理14.課程設(shè)計(jì)系統(tǒng)框圖及設(shè)計(jì)主要步驟35.利用MATLAB語言實(shí)現(xiàn)課程設(shè)計(jì)的源程序代碼46.源程序執(zhí)行結(jié)果57.設(shè)計(jì)總結(jié)98、參考書目10一、課程設(shè)計(jì)目的和作用：通信原理課程設(shè)計(jì)的目的是：使學(xué)生加深對所學(xué)的通信原理知識理解，培養(yǎng)學(xué)生專業(yè)素質(zhì)，提高利用通信原理知識處理通信系統(tǒng)問題的能力，為今后的專業(yè)課程的學(xué)習(xí)、畢業(yè)設(shè)計(jì)和工作打下良好的基礎(chǔ)。使學(xué)生能比較扎實(shí)地掌握本專業(yè)的基礎(chǔ)知識和基本理論，掌握數(shù)字通信系統(tǒng)及有關(guān)設(shè)備的分析、開發(fā)等基本技能，受到必要工程訓(xùn)練和初步的科學(xué)研究方法和實(shí)踐訓(xùn)練，增強(qiáng)分析和解決問題的能力，了解本通信專業(yè)的新

14、發(fā)展。二、課程設(shè)計(jì)內(nèi)容及要求：題目1：2ASK系統(tǒng)的設(shè)計(jì)目標(biāo)：（1）系統(tǒng)工作原理（2）設(shè)計(jì)系統(tǒng)（3）設(shè)定參數(shù)（碼速率，仿真時(shí)間，抽樣頻率，載頻，信噪比等），利用Matlab仿真 報(bào)告要求：（1）概述所作題目的意義、本人所做的工作及系統(tǒng)的主要功能； （2）調(diào)制解調(diào)原理及系統(tǒng)性能的描述；（3）軟件設(shè)計(jì)流程及描述；（4）源程序代碼（要有注釋）；（5）用matlab軟件仿真系統(tǒng)的各個(gè)部分的波形和頻譜圖。三、課程設(shè)計(jì)的基本原理1、通信的基本概念通信就是克服距離上的障礙，實(shí)現(xiàn)信息的傳輸與交換。通信系統(tǒng)是傳輸信息所需的一切技術(shù)設(shè)備的總稱。所有的消息必須轉(zhuǎn)換成電信號后才可以在通信系統(tǒng)中進(jìn)行傳輸。因此，信號是信

15、息的載體。相應(yīng)的信號可以分為模擬信號和數(shù)字信號。模擬信號的自變量可以是連續(xù)的或離散的，但是幅度是連續(xù)的。數(shù)字信號的自變量可以是連續(xù)多大或離散的，但是幅度是離散的。通信的目的是傳遞信息，但是對受信者有用的是信息中包含的有效內(nèi)容，也即信息。消息是具體的、表面的，而信息是抽象的、本質(zhì)的，且消息中包含的信息的多少可以用信息量來量度。通信技術(shù)，特別是數(shù)字通信技術(shù)近年來發(fā)展非常迅速，應(yīng)用也越來越廣泛。通信從本質(zhì)上講就是實(shí)現(xiàn)信息傳遞功能的一門學(xué)科，它要將大量有用的信息無失真、高效率地傳輸，同時(shí)還要在傳輸過程中將無用信息和有害信息抑制掉。當(dāng)今的通信不僅要有效地傳遞信息，而且還有儲存、處理、采集及顯示等功能，通

16、信已經(jīng)成為信息科學(xué)技術(shù)的一個(gè)重要的組成部分。通信系統(tǒng)可分為數(shù)字通信系統(tǒng)和模擬通信系統(tǒng)。數(shù)字通信系統(tǒng)是利用數(shù)字信號來傳遞消息的通信系統(tǒng)，模擬通信系統(tǒng)是利用模擬信號來傳遞消息的通信系統(tǒng)。數(shù)字通信系統(tǒng)與模擬通信系統(tǒng)相比有明顯的優(yōu)越性：抗干擾性強(qiáng)，且噪聲不積累；傳輸差錯(cuò)可控；便于用現(xiàn)代數(shù)字處理技術(shù)對數(shù)字進(jìn)行處理、變換、存儲；易于集成，使通信設(shè)備微型化，重量輕；易于加密處理，且保密性好。2、 數(shù)字帶通傳輸系統(tǒng)數(shù)字信號的傳輸方式分為基帶傳輸和帶通傳輸。然而實(shí)際中的大多數(shù)信道因具有帶通特性而不能直接傳輸基帶信號，這是因?yàn)閿?shù)字基帶信號往往有豐富的低頻分量。為使數(shù)字信號在帶通信道中傳輸，必須用數(shù)字基帶信號對載波

17、進(jìn)行調(diào)制，以使其相匹配，即為數(shù)字調(diào)制。調(diào)制信號是二進(jìn)制數(shù)字基帶信號時(shí)，這種調(diào)制稱為二進(jìn)制數(shù)字調(diào)制。在二進(jìn)制調(diào)制中，載波的振幅、頻率和相位只有兩種變化狀態(tài)。相應(yīng)的調(diào)制方式有二進(jìn)制振幅鍵控（2ASK）、二進(jìn)制頻移鍵控（2FSK）和二進(jìn)制相移鍵控（2PSK）。本次課程設(shè)計(jì)采用的是2ASK。其基本原理是：利用載波的幅度變化來傳遞數(shù)字信息，而頻率和初始相位保持不變。在2ASK中，載波的幅度只有兩種狀態(tài)，分別對應(yīng)二進(jìn)制信息的“0”或“1”。2ASK信號的產(chǎn)生方法通常有兩種：模擬調(diào)制法和鍵控法；解調(diào)方法為：非相干解調(diào)（包絡(luò)檢波法）和相干解調(diào)（同步檢測法）。解調(diào)的時(shí)候，添加一個(gè)抽樣判決器，是為了提高數(shù)字信號的

18、接受性能。3、2ASK的功率譜密度 由于2ASK是隨機(jī)的功率信號，故研究它的頻譜特性時(shí)，應(yīng)該討論它的功率譜密度。2ASK信號的功率譜由連續(xù)譜和離散譜兩部分組成；連續(xù)譜取決于經(jīng)線性調(diào)制后的雙邊帶譜，而離散譜由載波分量決定。2ASK信號的傳輸帶寬是碼元速率的2倍。四、課程設(shè)計(jì)的系統(tǒng)框圖及設(shè)計(jì)步驟1、課程設(shè)計(jì)按照以下系統(tǒng)框圖進(jìn)行設(shè)計(jì)：（1）發(fā)送端采用模擬法產(chǎn)生已調(diào)信號：若要產(chǎn)生2ASK信號，則基帶信號s(t)是單極性波形，若要產(chǎn)生2PSK信號，則基帶信號s(t)是雙極性波形；（2）將已調(diào)信號送入信道進(jìn)行傳輸：由于信道中常見的噪聲是高斯白噪聲，因而，假設(shè)信道是高斯白噪聲信道。已調(diào)信號在送入信道傳輸?shù)倪^

19、程中，疊加上高斯白噪聲。（3）信道輸出端信號的解調(diào)：這里采用同步解調(diào)法進(jìn)行解調(diào)，嚴(yán)格要求函數(shù)同頻同相；（4）基帶信號的恢復(fù)：對解調(diào)器的輸出進(jìn)行抽樣判決恢復(fù)基帶信號。2、下面對設(shè)計(jì)的各個(gè)步驟進(jìn)行簡要說明：（1）消息代碼的產(chǎn)生：本次設(shè)計(jì)，可以通過malab軟件的以下命令產(chǎn)生一串隨機(jī)的“0”、“1”消息代碼序列；（2）基帶信號的產(chǎn)生；（3）已調(diào)信號的產(chǎn)生；（4）已調(diào)信號通過白噪聲信道；（5）對信道輸出端混合信號中的噪聲進(jìn)行抑制；（6）信號的解調(diào)：信號先與同步載波相乘，再進(jìn)行低通濾波，這里濾波器還是以巴特沃斯為例，（7）基帶信號的恢復(fù)基帶信號的恢復(fù)需要三個(gè)步驟：抽樣、判決和碼元再生。（8） 系統(tǒng)性能分

20、析(選做)5、 利用MATLAB語言實(shí)現(xiàn)課程設(shè)計(jì)的源程序代碼%消息代碼的產(chǎn)生s=randint(1,10);xo=ones(1,100);s=kron(s,xo);figure(1)subplot(2,1,1);plot(s);title(2ASK基帶信號的時(shí)域波形);grid;subplot(2,1,2);plot(abs(fft(s);title(2ASK基帶信號的頻域波形);grid;%調(diào)制信號的產(chǎn)生t=1:1000;x=cos(2*pi*t/100);e=2*s.*x;figure(2)subplot(2,1,1);plot(e);title(2ASK已調(diào)制信號的時(shí)域波形);grid;

21、subplot(2,1,2);plot(abs(fft(e);title(2ASK已調(diào)制信號的頻域波形);grid;%加入高斯白噪聲后的調(diào)制信號n=awgn(e,20);figure(3)subplot(2,1,1);plot(n);title(加高斯白噪聲后的已調(diào)制信號的時(shí)域波形);grid;subplot(2,1,2);plot(abs(fft(n);title(加高斯白噪聲后的已調(diào)制信號的頻域波形);grid;%信號的解調(diào)z=x.*n; figure(4);subplot(2,1,1);plot(z);title(通過數(shù)字低通濾波器前的時(shí)域波形);grid;subplot(2,1,2);

22、plot(abs(fft(z);title(通過數(shù)字低通濾波器前的頻域波形);grid;wp=2*pi*6;ws=2*pi*40; N,wc=buttord(wp,ws,3,30,s);b1,a1=butter(N,wc,s);b1,a1=bilinear(b1,a1,1000);l=filter(b1,a1,z);figure(5);subplot(2,1,1);plot(l);title(通過數(shù)字低通濾波器后的時(shí)域波形);grid;subplot(2,1,2);plot(abs(fft(l);title(通過數(shù)字低通濾波器前的頻域波形);grid;%使函數(shù)通過抽樣判決器y1=1*(l0.5

23、); figure(6); %抽樣判決，門值為0.5subplot(2,1,1);plot(y1);title(通過抽樣判決器的時(shí)域波形);grid;subplot(2,1,2);plot(abs(fft(y1);title(通過抽樣判決器的頻域波形);grid; 六、源程序執(zhí)行結(jié)果七、 設(shè)計(jì)總結(jié)通過本次通信原理課程設(shè)計(jì)，再次溫習(xí)了數(shù)字通信系統(tǒng)的基本組成，同時(shí)也熟悉了數(shù)字通信涉及的技術(shù)問題，其中主要的有信源編碼與譯碼、信道編碼與譯碼、數(shù)字調(diào)制與解調(diào)、同步以及加密與解密等。本次課程設(shè)計(jì)雖然有的技術(shù)沒有用到，但是因此而忽視他們的這些技術(shù)的重要性。數(shù)字通信在通信系統(tǒng)中占有舉足輕重的地位。此外，在本次

24、的課程設(shè)計(jì)中，我們再一次運(yùn)用的MATLAB這個(gè)仿真工具，并利用這個(gè)它設(shè)計(jì)與實(shí)驗(yàn)相關(guān)的濾波器。我深深地感覺到MATLAB對于通信學(xué)子的重要性。總之，通過本次課程設(shè)計(jì)，我加深了對通信原理知識的理解，提高了處理自身通信系統(tǒng)問題的能力。參考書目：1 通信原理 樊昌信等編著 國防工業(yè)出版社2 現(xiàn)代通信系統(tǒng)-使用Matlab 劉樹棠譯 西安交通大學(xué)出版社3 通信原理基于matlab的計(jì)算機(jī)仿真 郭文斌等編著 北京郵電大學(xué)出版社grass-roots party organizations is focus of new party members. Further strengthening the pa

25、rty education campaign, party organization to more excellent talents absorbed, constantly enhance the partys vitality and vigor, a solid job discovery, training activists. The initiative to broaden the scope of training, at the village level organization of young cadres, wealth experts and other per

26、sonnel in the discovery, selection, training, and guide them to move closer to the party and injected fresh vitality to the building of rural grass-roots party organizations. Second is to further improve the site present situation of grass-roots party branches. With an emphasis on construction of vi

27、llage-level activities, comprehensive corrosion activities of grass-roots party organization construction in various fields, with village-level party organization function setting, achieving more efficient use of venues, activities for grass-roots party organizations and party members, and create go

28、od conditions for serving the masses, by using village-level activities. Third is to conscientiously implement the village group living subsidy distribution work. In strict accordance with the parent document, fully according to the actual situation, further improve the village cadres of the group r

29、egistration through the one card uniform forms, living subsidies timely payment on time each month to the hands of village cadres of the group, to ensure, without delay, not in arrears, and to ensure that earmarks. Four village election preparations are made. Organization survey and the Xiang villag

30、e cadres, a comprehensive understanding of the village Committee. Using visited members, and masses representative and village group cadres of form, understand masses by wants to, and by needed, and by hope; through held members will, and masses will and village group cadres will, understand village

31、 level organization status, and exists highlight problem and future development direction; visited understand complex back soldiers, and workers returned young personnel and masses recommended of rich capable, full reserve cadres team, for village two Board general election lay solid based. (C) to s

32、peed up the pace of the adjustment of industrial structure and increase farmers income through various channels. One is to strengthen its efforts to readjust the industrial structure. At the same time accelerate the process of industrialization in rural areas, and actively promote the development of industries with lo