cheb2mag - response of type 2 Chebyshev filter

Calling Sequence

[h2]=cheb2mag(n,omegar,A,sample)

Parameters

• n : integer ; filter order
• omegar : real scalar : cut-off frequency
• A : attenuation in stop band
• sample : vector of frequencies where cheb2mag is evaluated
• h2 : vector of Chebyshev II filter values at sample points

Description

Square magnitude response of a type 2 Chebyshev filter.

omegar = stopband edge, sample = vector of frequencies where the square magnitude h2 is desired.

Examples

//Chebyshev; ripple in the stopband
n=10;omegar=6;A=1/0.2;sample=0.0001:0.05:10;
h2=cheb2mag(n,omegar,A,sample);
plot(sample,log(h2)/log(10),'frequencies','magnitude in dB')
//Plotting of frequency edges
minval=(-maxi(-log(h2)))/log(10);
plot2d([omegar;omegar],[minval;0],[2],"000");
//Computation of the attenuation in dB at the stopband edge
attenuation=-log(A*A)/log(10);
plot2d(sample',attenuation*ones(sample)',[5],"000")
 

See Also

cheb1mag