An audio signal s (t) generated by a loudspeaker is reflected at two different walls wit...

An audio signal s (t) generated by a loudspeaker is reflected at two different walls with reflection coefficients r₁ and r₂. The signal x(t) recorded by a microphone close to the loudspeaker, after sampling, is

where k₁ and k₂ are the delays of the two echoes.

(a) Determine the autocorrelation r_xx(l) of the signal x(n).

(b) Can we obtain n , r₂, k_l, and k₂ by observing r_xx (1) ?

(c) What happens if r₂ = 0?