Code covered by the BSD License

FFT analysis of Rectified sine waves

by

Arun GK (view profile)

Fourier analysis of simple sine wave of 10Hz with Half and full wave Rectification

HW_FW_FFT_analysis.m
```clc
clear
close
%%%%%%%%%% Creating a time vector from 0 to 1 sampled at 100 Hz
fs=100
t=0:1/fs:1;

%%%%%%%Create a sine wave of frequency 10 Hz
f=10
y=sin(f*2*pi*t);
subplot(6,1,1)
plot(t,y)
title('10Hz sine wave')
grid
N=1024;
%%%%%%%%% Compute the N point FFT of the signal
Y=abs(fft(y,N));
%%%%%%%%%%%%%%%Centre at zero
Y=fftshift(Y);
F=[-N/2:N/2-1];
subplot(6,1,2)
F=F/f
plot(F,Y)
title('FFT of the 10Hz signal sampled at 100Hz')
grid
%%%%%%Full-Wave Rectified
n=sin(10*2*pi*t);
%%%%%%%%%%%% Rectifying the 10Hz signal
x=y.*(y>=0)-n.*(n<=0);
subplot(6,1,3)
plot(t,x)
grid
title('Full-Wave Rectified signal')
X=abs(fft(x,N));
X=fftshift(X);
subplot(6,1,4)
plot(F,X)
grid
title('FFT of Full-Wave Rectified signal')
grid
x=y.*(y>=0);
subplot(6,1,5)
plot(t,x)
grid
title('Half-Wave Rectified signal')
X=abs(fft(x,N));
X=fftshift(X);
subplot(6,1,6)
plot(F,X)
title('FFT of Half-Wave Rectified signal')
grid

```