Howtosignalprocessing
- What is the effect of increasing size of DFT on spectrum?
- Does zero padding increase resolution?
- How many points do you need for FFT?
- What is zero padding in FFT?
What is the effect of increasing size of DFT on spectrum?
The DFT of the window is what would convolve with our original frequencies. As the time length of the window increases, the width of the main lobe of its transform in frequency gets more narrow (the nulls are located at 1/T) and therefore the frequency resolution increases.
Does zero padding increase resolution?
Zero padding enables you to obtain more accurate amplitude estimates of resolvable signal components. On the other hand, zero padding does not improve the spectral (frequency) resolution of the DFT. The resolution is determined by the number of samples and the sample rate.
How many points do you need for FFT?
Because the FFT function uses a base 2 logarithm by definition, it requires that the range or length of the time series to be evaluated contains a total number of data points precisely equal to a 2-to-the-nth-power number (e.g., 512, 1024, 2048, etc.).
What is zero padding in FFT?
``Zero-padding'' means adding additional zeros to a sample of data (after the data has been windowed, if applicable). For example, you may have 1023 data points, but you might want to run a 1024 point FFT or even a 2048 point FFT.
