Use of FFT to compute frequency response [duplicate]

1. What is the FFT used for?
2. How do you find the frequency of data using FFT?
3. What is the main advantage of FFT?
4. What the FFT analysis of a signal tells us about the signal?

What is the FFT used for?

The FFT is used to process data throughout today's highly networked, digital world. It allows computers to efficiently calculate the different frequency components in time-varying signals—and also to reconstruct such signals from a set of frequency components.

How do you find the frequency of data using FFT?

Let X = fft(x) . Both x and X have length N . Suppose X has two peaks at n0 and N-n0 . Then the sinusoid frequency is f0 = fs*n0/N Hertz.

What is the main advantage of FFT?

The main advantage of an FFT is speed, which it gets by decreasing the number of calculations needed to analyze a waveform.

What the FFT analysis of a signal tells us about the signal?

The output of the FFT is a complex vector containing information about the frequency content of the signal. The magnitude tells you the strength of the frequency components relative to other components. The phase tells you how all the frequency components align in time.