designing the following band stop filters:

please can someone help me answer the below question on MATLAB .i am really struggling to do so.help will be APPRECIATED.THANKS.

Design the following band stop filters and plot and compare their magnitude responses. The specifications for the filters are: 20π < fc < 40π, Pass band ripple (Rp) = 0.2, Stop band ripple (Rs) = 30 i. 4th order Butterworth ii. 4th order Chebychev Type 1 iii. 4th order Chebychev Type 2 iv. 4th order Elliptic

i would prefer the coding with explanation on MATLAB.I hope you will help me out.i am a novice at matlab.

[Jan]

Please read http://www.mathworks.com/matlabcentral/answers/8626-how-do-i-get-help-on-homework-questions-on-matlab-answers

Answer 1

[santz]

thanks @jan simon. you were the best help in the world.loved your sarcastic answers. to others who really wish to help i had a go at making the 4th order butterworth bandstop filter.this is how my code looks and i get a graph but i dont know if it is correct for a butterworth bandstop. I know that the butterworth filter does not have any ripples( but thats all i know about butterworth filters) my graph does not look like a bandstop filter.it looks like a high pass filter(with the signal magnitude increasing(y axis) as the frequency increases(x axis).this is how my code looks

fp=20*pi;

fs=40*pi;

Fc=[fp fs];

N=4;

[b,a]=butter(N,Fc,'stop','s');

fvtool(b,a);

Answer 2

[santz]

am i on the right lines?? for doing part a.