Question

If the arrangement is of the form in which the first row consists of the first M elements of x(n), the second row consists of the next M elements of x(n), and so on, then which of the following mapping represents the above arrangement?

(a) n=l+mL

(b) n=Ml+m

(c) n=ML+l

(d) none of the mentioned

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I'm obligated to ask this question of Efficient Computation of DFT FFT Algorithms topic in chapter DFT Efficient Computation – Fast Fourier Transform Algorithms of Digital Signal Processing

Answer 1

The correct choice is (b) n=Ml+m

Best explanation: If we consider the mapping n=Ml+m, then it leads to an arrangement in which the first row consists of the first M elements of x(n), the second row consists of the next M elements of x(n), and so on.