diff --git a/SAR.mlx b/SAR.mlx new file mode 100644 index 0000000000000000000000000000000000000000..2c4568586c1cb040390f7301a24ff028c4ea2181 Binary files /dev/null and b/SAR.mlx differ diff --git a/question_21.asv b/question_21.asv deleted file mode 100644 index 39cb74bcb0ed337ae10e6e9513677697e6960aa7..0000000000000000000000000000000000000000 --- a/question_21.asv +++ /dev/null @@ -1,68 +0,0 @@ -fe = 10e3; % Fréquence d'échantillonnage -T = 1/10; -Te=1/fs; -t = -1:1/fs:1; % Durée du signal - - -x_1 =square(2*pi*t/T); - -%fft -X_1 = 10*log10(abs(fftshift(fft(x_1)))); -N =length(t) ; -freq = (-N/2:N/2-1)*(1/(Te*N)); - -figure; -stem(freq, X_1, '.') % Tracé du signal -xlabel('f (Hz)') -ylabel('10log(|X_1|)') -title('spectre du signal carré'); - - -x_2 = sawtooth(2*pi*t/T); -plot(t,x_2) -title('sawtooth') - -%fft -X_2 = 10*log10(abs(fftshift(fft(x_2)))); - -figure; -stem(freq, X_2, '.') -xlabel('f (Hz)') -ylabel('10log(|X_1|)') -title('spectre du signal en dent de scie'); - -%question 2.2------------------------------------------ - -% Filtrage : y(k) = 1/2 (x(k) + x(k-1)) -b=[1/2,1/2]; -a=1; -y = filter(a,b,x_1); - - -% FFT -X1 = 20*log10(abs(fftshift(fft(x_1)))); -Y = 20*log10(abs(fftshift(fft(y)))); -f = (-N/2:N/2-1)*(1/(Te/N)); % Axe fréquentiel -f_lin=linspace(-1/(2*Te),1/(2*Te),N); -disp(f_lin) - - -% Réponse théorique du filtre -H = (1/2*abs(1+exp(-2*1i*pi*f_lin*Te))).^2; - -% Affichage -figure; -subplot(3,1,1); -plot(t, x_1); title('Signal d''entrée x(k)'); - -subplot(3,1,2); -plot(t, y); title('Signal filtré y(k)'); - -subplot(3,1,3); -plot(f_lin, abs(Y), 'b', 'DisplayName', '|Y(f)|^2'); -hold on; -plot(f_lin, abs(X2).*H, 'r', 'DisplayName', '|X(f)|^2 × |H(f)|^2 (théorique)'); -legend; xlabel('Fréquence (Hz)'); -title('Spectre de sortie comparé à la théorie'); -xlim([-10 10]); -