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Matlab implementation of fast fourier transform
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MATLAB IMPLEMENTATION OF FFT PROF. RAKESH K. JHA CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION MATLAB IMPLEMENTATION OF FAST FOURIER TRANSFORM % fft of 10 hz and 20 hz signal clear all; clc; close all; fs= 100; f1=10 ; f2= 20 ; nfft=1024; %plot 10 hz signal t=-1:1/fs:1; y1= sin(2*pi*f1*t); figure; plot(t,y1) xlabel('----->t'); ylabel('sin(2*pi*f1*t)'); title('10 hz ferquency signal'); %plot 20 hz signal t=-1:1/fs:1; y2= sin(2*pi*f2*t); figure; plot(t,y2) xlabel('----->t'); ylabel('sin(2*pi*f2*t)'); title('20 hz ferquency signal'); %addition of two signals y3= y1+y2; figure; plot(t,y3) xlabel('----->t'); ylabel('sin(2*pi*f1*t)+sin(2*pi*f2*t)'); title(' addition of two signal'); % appended signal y4=[y1,y2]; figure plot(y4); xlabel('---->t'); ylabel('appended signal'); title(' plot appending of two signals'); %fft of y1 x1= fft(y1,nfft) x1= x1(1:nfft/2) mx1= abs(x1); f=(1:nfft/2)*fs/nfft; figure plot(f,mx1); xlabel(' frequency in hz'); ylabel('power'); title('fft of 10 hz signal'); %fft of y2 x2= fft(y2,nfft); x2=x2(1:nfft/2); mx2= abs(x2); f=(0:nfft/2-1)*fs/nfft; figure plot(f,mx2);
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Transcript of Matlab implementation of fast fourier transform
MATLAB IMPLEMENTATION OF FFT PROF. RAKESH K. JHA
CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
MATLAB IMPLEMENTATION OF FAST FOURIER TRANSFORM % fft of 10 hz and 20 hz signal clear all; clc; close all; fs= 100; f1=10 ; f2= 20 ; nfft=1024; %plot 10 hz signal t=-1:1/fs:1; y1= sin(2*pi*f1*t); figure; plot(t,y1) xlabel('----->t'); ylabel('sin(2*pi*f1*t)'); title('10 hz ferquency signal'); %plot 20 hz signal t=-1:1/fs:1; y2= sin(2*pi*f2*t); figure; plot(t,y2) xlabel('----->t'); ylabel('sin(2*pi*f2*t)'); title('20 hz ferquency signal'); %addition of two signals y3= y1+y2; figure; plot(t,y3) xlabel('----->t'); ylabel('sin(2*pi*f1*t)+sin(2*pi*f2*t)'); title(' addition of two signal'); % appended signal y4=[y1,y2]; figure plot(y4); xlabel('---->t'); ylabel('appended signal'); title(' plot appending of two signals'); %fft of y1 x1= fft(y1,nfft) x1= x1(1:nfft/2) mx1= abs(x1); f=(1:nfft/2)*fs/nfft; figure plot(f,mx1); xlabel(' frequency in hz'); ylabel('power'); title('fft of 10 hz signal'); %fft of y2 x2= fft(y2,nfft); x2=x2(1:nfft/2); mx2= abs(x2); f=(0:nfft/2-1)*fs/nfft; figure plot(f,mx2);
MATLAB IMPLEMENTATION OF FFT PROF. RAKESH K. JHA
CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
xlabel(' frequency in hz'); ylabel('power'); title('fft of 20 hz signal'); % fft of added signal y3 x3= fft(y3,nfft); x3=x3(1:nfft/2); mx3= abs(x3); f=(0:nfft/2-1)*fs/nfft; figure plot(f,mx3); xlabel(' frequency in hz'); ylabel('power'); title('fft of added signal'); %fft of appended signal x4= fft(y4,nfft); x4=x4(1:nfft/2); mx4=abs(x4); f=(0:nfft/2-1)*fs/nfft; figure plot(f,mx4); xlabel(' frequency in hz'); ylabel('power'); title('fft of appended signal');
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MATLAB IMPLEMENTATION OF FFT PROF. RAKESH K. JHA
CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
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MATLAB IMPLEMENTATION OF FFT PROF. RAKESH K. JHA
CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
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CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
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CORPORATE INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL ( INDIA) DEPARTMENT OF ELECTRONICS & COMMUNICATION
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