Echo removal by linear filtering - impulse response of the echo removal system - analythical solution Consider an echo removal system defined by the difference equation y[n] + ay[n – N] = x[n] In the above system, x[n] is the input signal and y[n] is the output signal. This is an echo removal system, so the input siganl, x[n], is a signal that has an echo and the output, y[n], is the signal which has the echo removed. N = 10000 and a = 0.5. Part 1. Find the impulse response of the above echo removal system (analythical solution: hand- written or typed). Part 2. Does this impulse response have a finite length or an infinite length?