DFT of sine wave
14 views (last 30 days)
Show older comments
Hello,
I have to calculate the DFT of the following signals sampled at 32 kHz. Plot the magnitude, phase, real and imaginary parts of the DFT coefficients.
I know that to generate plots I have to use these functions: abs, angle, real, imag
I really could use some help.
The given signal is: x = sin(2pi*8000*t + pi/8), signal length: 8 samples
I am able to create function that would be without that 'pi/8' part, no idea how to add this to my function :/ ..
As far as I am concerned, the function without my problem looks like:
n=8
fs=32000
fsin=8000
A=1
df=(2*pi)
k=0: n-1;
x=A*sin((2*pi)*fsin.*k/fs + df);
X=fft(x);
fr=k*fs/n;
figure
subplot(312)
stem(fr, real(X))
title("real");
subplot(311)
stem(fr, imag(X))
title("imaginary")
But unfortunately I have no idea how to add the pi/8 part..
Thanks in advance for every hint..
1 Comment
Sindar
on 30 Apr 2020
It looks like you have added the pi/8, what's the problem? Are you trying to write an analytic expression for the fourier components?
Answers (1)
Raunak Gupta
on 3 May 2020
Hi,
It looks like ‘df’ in the above code can be set to ‘pi/8’ to represent time shift in original signal. Other than that everything looks fine.
0 Comments
See Also
Categories
Find more on Multirate Signal Processing in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!