Question

Decimation-in frequency FFT algorithm is used to compute H(k).

(a) True

(b) False

The question was asked by my college director while I was bunking the class.

This intriguing question comes from Applications of FFT Algorithms topic in portion DFT Efficient Computation – Fast Fourier Transform Algorithms of Digital Signal Processing

Answer 1

Correct choice is (a) True

To explain I would say: The N-point DFT of h(n), which is padded by L-1 zeros, is denoted as H(k). This computation is performed once via the FFT and resulting N complex numbers are stored. To be specific we assume that the decimation-in frequency FFT algorithm is used to compute H(k). This yields H(k) in the bit-reversed order, which is the way it is stored in the memory.