Suppose s c (t) is a speech signal with the continuous-time Fourier transform S c (j) shown

Suppose s_c(t) is a speech signal with the continuous-time Fourier transform S_c(jΩ) shown in Figure. We obtain a discrete-time sequence s_r[n] from the system shown in Figure, where H(e^jω) is an ideal discrete-time lowpass filter with cutoff frequency ω_c and a gain of unity throughout the passband, as shown in Figure. The signal s_r[n] will be used as an input to a speech coder, which operates correctly only on discrete-time samples representing speech sampled at an 8-kHz rate, Choose values of L, M, and ω_c that produce the correct input signal s_r[n] for the speech coder.

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| S,(jN) -2п . 4000 2т 4000 0(гаd/s) | sy[n] Не) s[n] м [4]"s s,[r] s(t) C/D T = (1/44.1) ms