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The total number of complex multiplications required to compute N point DFT by radix-2 FFT is?

The total number of complex multiplications required to compute N point DFT by radix-2 FFT is? Correct Answer (N/2)log2N

The decimation of the data sequence should be repeated again and again until the resulting sequences are reduced to one point sequences. For N=2v, this decimation can be performed v=log2N times. Thus the total number of complex multiplications is reduced to (N/2)log2N.

Related Questions

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