Why exactly is a bit/radix reverse required when calculating the fft?

1. Why is bit reversal needed for FFT?
2. What is the purpose of bit reversal?
3. What is bit reversal in FFT?
4. How is bit reverse addressing used in FFT computations?

Why is bit reversal needed for FFT?

FFT and IFFT Blocks Data Order

The FFT block enables you to output the frequency indices in linear or bit-reversed order. Because linear ordering of the frequency indices requires a bit-reversal operation, the FFT block may run more quickly when the output frequencies are in bit-reversed order.

What is the purpose of bit reversal?

There are two extensions of the bit-reversal permutation to sequences of arbitrary length. These extensions coincide with bit-reversal for sequences whose length is a power of 2, and their purpose is to separate adjacent items in a sequence for the efficient operation of the Kaczmarz algorithm.

What is bit reversal in FFT?

“Bit reversal” is just what it sounds like: reversing the bits in a binary word from left to right. Therefore the MSBs become LSBs and the LSBs become MSBs.

How is bit reverse addressing used in FFT computations?

Bit-reversed addressing is a special feature provided in the dsPIC^® architecture to support efficient implementation of FFT algorithms. Given the address of a particular element in the array, the dsPIC hardware automatically computes the address of the next element in the bit-reversed sequence.