Filter Approximation Theory

Approximation Polynomials

Definitions

Definitions - 2

Filter Specification

Butterworth

Butterworth Continued

Butterworth Filter
|H(s)| for n=4

Chebyshev – Type 1

Chebyshev
|H(s)| for n=4, r=1 (Type 1)

Elliptic Function

Elliptic Function
H(s) for n=4, r_p=3, r_s=50

Bessel Filter

Practical Filter Design