1. Communication optiqueCompte rendu TP1TOUATI KARIM / IMI 4 /Groupe E 2. compte renducommunication optiquemodulation d'amplitude>> fs=100;>> t=[0:2*fs+1]'/fs;>> fc=10;>> x=sin(2*pi*t);>> ydouble=ammod(x,fc,fs);>> zdouble=fft(ydouble);>> zdouble=abs(zdouble(1:length(zdouble)/2+1));>> subplot(2,1,1);>> frqdouble=[0:length(zdouble)-1]*fs/length(zdouble)/2;>> title('spectrum of double side-bandsignal');>> plot(frqdouble,zdouble);>> subplot(2,1,1);>> ydouble=ammod(x,fc,fs,0,1);>> plot(frqdouble,zdouble);>> subplot(2,1,1);>> ydouble=ammod(x,fc,fs,0,1);>> zdouble=fft(ydouble);>> zdouble=abs(zdouble(1:length(zdouble)/2+1));>> subplot(2,1,1);>> frqdouble=[0:length(zdouble)-1]*fs/length(zdouble)/2;>> title('spectrum of double side-bandsignal');>> plot(frqdouble,zdouble);>> ydouble=ssbmod(x,fc,fs);>> zdouble=fft(ydouble);>> zdouble=abs(zdouble(1:length(zdouble)/2+1));>> subplot(2,1,1);>> frqdouble=[0:length(zdouble)-1]*fs/length(zdouble)/2;>> plot(frqdouble,zdouble);>> ydouble=ssbmod(x,fc,fs,1,'upper');>> zdouble=fft(ydouble);>> zdouble=abs(zdouble(1:length(zdouble)/2+1));>> subplot(2,1,1);>> frqdouble=[0:length(zdouble)-1]*fs/length(zdouble)/2;>> plot(frqdouble,zdouble);2 3. Aprs la modulation le signal est translat autour de Fc:0 5 10 15 20 25 30 35 40 45 50100806040200plot(t,x,t,ydouble);0 0.5 1 1.5 2 2.510.50-0.5-1-1.53 4. modulation de frquence d'un signalfs=8000;>> fc=3000;>> t=[0:50:fs]'/fs;>> s1=sin(2*pi*300*t)+2*sin(2*pi*600*t);>> s2=sin(2*pi*150*t)+2*sin(2*pi*900*t);>> x=[s1,s2];>> dev=50;>> y=fmmod(x,fc,fs,dev);>> z=fmdemod(y,fc,fs,dev);>> figure(1),plot(y);title0 20 40 60 80 100 120 140 160 18010.50-0.5-14 5. figure(2),plot(z);tilte50-5-10-15-20-250 20 40 60 80 100 120 140 160 180m=16;>> k=log2(m);>> n=3e4;>> x=randint(n,1);>> stem(x(1:40),'filed');>> stem(x(1:40),'filled');>> title('random bits');>> xlabel('bit index');>> ylabel('binarg value');>> Nxsym=length(xsym);*>> xsym=bi2de(reshape(x,k,length(x)/k).','left-msb');>> Nxsym=length(xsym);>> title('random symbols');>> xlabel('symbol index')>> ylabel('integer value');>> xlabel('symbol index');5 6. 10.50random symbols0 5 10 15 20 25 30 35 40symbol indexinteger value6 7. 10.50random symbols0 5 10 15 20 25 30 35 40symbol indexinteger value6