Increase fft resolution

The most intuitive way to increase the frequency resolution of an FFT is to increase the size while keeping the sampling frequency constant. Doing this will increase the number of frequency bins that are created, decreasing the frequency difference between each.

1. Does zero padding improve FFT resolution?
2. How do you increase the resolution of a spectrum?
3. What is the resolution of the FFT?
4. How does sample rate affect FFT?

Does zero padding improve FFT 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 do you increase the resolution of a spectrum?

The way to increase your STFT's spectral resolution is to increase the duration of time that the transform covers, as you noted. If you truly need to be able to resolve frequencies that precisely (within a few Hz of one another), then you need to observe them for a long enough period of time to discern them.

What is the resolution of the FFT?

Frequency resolution is 10 Hz. The time waveform with length of 0.1 seconds is used for an FFT analysis. The spectrum values are obtained by performing FFT every 10 Hz. The spectrum cannot be obtained with the fractional frequency component values, such as 995, 1001 Hz.

How does sample rate affect FFT?

The amplitude of the DFT (FFT) is proportional to the number of samples. Therefore, if you sample for twice as long at the same sampling frequency, or if you sample for the same duraiton but twice as fast, you will have twice as many data points, and the DFT amplitude will be twice as large. See examples below.