Tema semnal

3)Sa se genereze 3 perioade de semnal triunghiular avand zgomot de 5%.Sa se calculeze valoarea medie a semnalului si sa se reprezinte graphic variatia acestei valori in functie de numarul N=300,600,900,1200,1500.

N=[300 600 900 1200 1500];for j=1:length(N) n=N(j)fi=1:n; for i=1:n/6tr(i)=i;end for i=n/6:n/3tr(i)=-i+n/3;end for i=n/3:3*n/6tr(i)=i-n/3;end for i=3*n/6:2*n/3tr(i)=-i+2*n/3;end for i=2*n/3:5*n/6tr(i)=i-2*n/3;end for i=5*n/6:ntr(i)=-i+n;end for i=1:ns(i)=n/10*sin(6*pi/n*i);endm=max(s); for i=1:nif s(i)>0tr(i)=tr(i)+rand*m/5;elsetr(i)=tr(i)+rand*m/5;end

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endvmed(j)=sum(tr)/nend

plot(fi,tr)

vmed =[ 545.9560 268.7972 162.3842 143.1483 132.6033]

4)Sa se traseze curbele de eroare pentru valoarea medie si valoarea efectiva ale unui semnal sinusoidal avand un zgomot de 5% din amplitudine pentru un numar de esantioane N=10,20,40,80,160,320,640,1280,2560,5120,10240.

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n=[10 20 40 80 160 320 640 1280 2560 5120 10240];for j=1:length(n) m=n(j);fi=1:m;for i=1:ms(i)=sin(2*pi/m*i)+0.05*rand;endumin=min(s);umax=max(s);umed(j)=sum(s)/m;uef(j)=(umax-umin)/2;end x=1:length(n);figure;subplot(2,1,1) plot(x,umed);subplot(2,1,2)plot(x,uef);

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