Interpolation of magnitude of discrete Fourier transform (DFT)

1. What is interpolation in DFT?
2. What is magnitude DFT?
3. What is FFT interpolation?
4. How do you plot magnitude of DFT in Matlab?

What is interpolation in DFT?

Based on the achieved expressions, the interpolated DFT algorithms are generalized and a novel frequency estimator with high image component interference rejection is proposed. Simulation results show that the frequency errors returned by the new algorithm are very small even though only one or two cycles are obtained.

What is magnitude DFT?

Thus, the output magnitude of the DFT is proved as AN . For a real sinusoid, sQ[n] s Q [ n ] is 0 and only the first term in I part of the above equation survives. Since cos2A=1/2(1+cos2A) ⁡ A = 1 / 2 ( 1 + cos ⁡ , the output magnitude of the DFT for a real sinusoid is AN/2 A N / 2 .

What is FFT interpolation?

FFT interpolation is based on adding zeros at higher frequencies of the Fourier coefficient vector. In such way, the inverse FFT will produce more output, using the same non-zero Fourier coefficients.

How do you plot magnitude of DFT in Matlab?

To plot the magnitude and phase in degrees, type the following commands: f = (0:length(y)-1)*100/length(y); % Frequency vector subplot(2,1,1) plot(f,m) title('Magnitude') ax = gca; ax. XTick = [15 40 60 85]; subplot(2,1,2) plot(f,p*180/pi) title('Phase') ax = gca; ax.