find_freq

Arguments

epsilon

passband ripple

A

stopband attenuation

n

filter order

m

frequency needed for construction of elliptic filter

Description

Search for m such that n=K(1-m1)K(m)/(K(m1)K(1-m)) with

m1=(epsilon*epsilon)/(A*A-1);

If m = omegar^2/omegac^2, the parameters epsilon,A,omegac,omegar and n are then compatible for defining a prototype elliptic filter. Here, K=%k(m) is the complete elliptic integral with parameter m.

See also

• %k — Jacobi's complete elliptic integral of the first kind (vectorized)