A 128-millisecond portion of an analog signal is sampled at a rate of 8 kHz and the resulting L samples are saved for further processing. What is L? The 256-point DFT of these samples is computed. What is the frequency spacing in Hz of the computed DFT values? What is the total number of required multiplications: (a) if the computations are done directly using the definition of the DFT, (b) if the L samples are first wrapped modulo 256 and then the 256-point DFT is computed, and (c) if a 256-point FFT is computed of the wrapped signal?
