FFT calculation problem

1. How do you calculate FFT?
2. Why do we calculate FFT?
3. What is 1024 point FFT?
4. How many computations are in a FFT?

How do you calculate FFT?

Signal Processing, Digital

In the FFT formula, the DFT equation X(k) = ∑x(n)W_N^nk is decomposed into a number of short transforms and then recombined. The basic FFT formulas are called radix-2 or radix-4 although other radix-r forms can be found for r = 2^k, r > 4.

Why do we calculate FFT?

The "Fast Fourier Transform" (FFT) is an important measurement method in the science of audio and acoustics measurement. It converts a signal into individual spectral components and thereby provides frequency information about the signal.

What is 1024 point FFT?

A 1024-point, 32-bit, fixed, complex FFT processor is designed based on a field programmable gate array (FPGA) by using the radix-2 decimation in frequency (DIF) algorithm and the pipeline structure in the butterfly module and the ping-pone operation in data storage unit.

How many computations are in a FFT?

Each pair requires 4 additions and 4 multiplications, giving a total number of computations equaling 8N4=N2. This number of computations does not change from stage to stage. Because the number of stages, the number of times the length can be divided by two, equals log2N, the complexity of the FFT is O(NlogN).