38 lines
712 B
Matlab
38 lines
712 B
Matlab
close all;
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clear all;
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% PARAMS
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Fs = 1000; % Sampling frequency
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T = 1/Fs; % Sampling period
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L = 1500; % Length of signal
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t = (0:L-1)*T; % Time vector
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% SIGNAL
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S = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t);
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% FINAL SIGNAL
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%X = S + 2*randn(size(t));
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X = S;
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% PLOT TIME DOMAIN
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figure(1)
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plot(1000*t(1:50),X(1:50))
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title('Signal Corrupted with Zero-Mean Random Noise')
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xlabel('t (milliseconds)')
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ylabel('X(t)')
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% CALCULATE FFT
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Y = fft(X);
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P2 = abs(Y/L);
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P1 = P2(1:L/2+1);
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P1(2:end-1) = 2*P1(2:end-1);
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f = Fs*(0:(L/2))/L;
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% PLOT FREQ DOMAIN
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figure(2)
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plot(f,P1)
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title('Single-Sided Amplitude Spectrum of X(t)')
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xlabel('f (Hz)')
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ylabel('|P1(f)|') |