An audio signal s(t) generated by a loudspeaker is reflectedat two different walls with reflection coefficientsr1 and r2. The signal x(t)recorded by a microphone close to the loudspeaker, after sampling,is:
x(n) = s(n) + r1s(n-k1) +r2s(n-k2)
Where k1 and k2 are the delays of thetwo echoes.
a.) Determine the autocorrelation rxx(l) of thesignal x(n).
b.) Can we obtain r1, r2, k1and k2 by observing rxx(l)?
c.) What happens if r2 = 0?