Question

Question 2: (25 Marks) The Impulse response h(n) of a filter is non zero over the index range of n be [5,8]. The input signal x(n) to this filter is non zero over the index range of n be [7,12]. Consider the direct and LTI forms of convolution y(n)-Σh(m) x(-m)- Σχm)h (n -m) m a. Determine the overall index range n for the output y(n). For each n, determine the corresponding summation range over m, for both the direct and LTI forms. b. Assume h(n) = 0.4n and x(n)=1 over their respective index ranges. Calculate and sketch the output y(n). Identify (with an explanation) the input on/off transient and steady state parts of y(n).

Answer 1

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