Question

What is the general system function of an FIR system?

(a) \(\sum_{k=0}^{M-1}b_k x(n-k)\)

(b) \(\sum_{k=0}^M b_k z^{-k}\)

(c) \(\sum_{k=0}^{M-1}b_k z^{-k}\)

(d) None of the mentioned

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This interesting question is from Structures for FIR Systems in portion Discrete Time Systems Implementation of Digital Signal Processing

Answer 1

Right answer is (c) \(\sum_{k=0}^{M-1}b_k z^{-k}\)

Explanation: We know that the difference equation of an FIR system is given by y(n)=\(\sum_{k=0}^{M-1}b_k x(n-k)\).

=>h(n)=bk=>\(\sum_{k=0}^{M-1}b_k z^{-k}\).