0
1.7kviews
Write a note on frequency sampling realization of FIR filter.
1 Answer
written 6.5 years ago by |
We know that,
DFT of h(n) is given by:
H(k)=∑N−1n=0h(n)e−j2πknN …………………(1)
From the equation of IDFT we have,
h(n)=1N∑N−1k=0H(k)ej2πknN…………………(2)
By the definition of Z transform we have,
$H(z)=∑_{n=0}^{N-1}h(n) z^{-n}$…………………(3)
Put the value of h(n) from equation (2) to equation (3), we get
H(z)=∑N−1n=01N∑N−1k=0H(k)ej2πknNz−n
H(z)=1N∑N−1k=0H(k)∑N−1n=0ej2πknNz−n
Now by sum of finite GP series we have;
We know that, ej2πk=1
H(z)=(1−z−N)N∑N−1k=0[H(k)(1−ej2πkNz−1)]
H(z)=(1−z−N)N[H(0)(1−z−1)+H(1)(1−ej2πNz−1)+H(2)(1−ej4πNz−1)+⋯………………+H(N−1)(1−e(j2π(N−1))Nz−1)]
Frequency Sampling Realization;