function Hd = bandpass_filter_design(Fs)

%
% MATLAB Code
% Generated by MATLAB(R) 7.14 and the Signal Processing Toolbox 6.17.
%
% Generated on: 23-Apr-2013 18:34:23
%

% Fstop1 = 0.001;  % First Stopband Frequency
% Fpass1 = 5;      % First Passband Frequency
% Fpass2 = 35;     % Second Passband Frequency
% Fstop2 = 50;     % Second Stopband Frequency
% Astop1 = 20;     % First Stopband Attenuation (dB)
% Apass  = 1;      % Passband Ripple (dB)
% Astop2 = 20;     % Second Stopband Attenuation (dB)
% % Fs     = 1000;   % Sampling Frequency
% 
% h = fdesign.bandpass('fst1,fp1,fp2,fst2,ast1,ap,ast2', Fstop1, Fpass1, ...
%     Fpass2, Fstop2, Astop1, Apass, Astop2, Fs);
% 
% Hd = design(h, 'butter', ...
%     'MatchExactly', 'stopband');


N     = 100;  % Order
Fpass = 35;   % Passband Frequency
Fstop = 50;   % Stopband Frequency
Wpass = 1;    % Passband Weight
Wstop = 100;  % Stopband Weight

% Calculate the coefficients using the FIRLS function.
b  = firls(N, [0 Fpass Fstop Fs/2]/(Fs/2), [1 1 0 0], [Wpass Wstop]);
Hd1 = dfilt.dffir(b);

Fstop = 0.01;        % Stopband Frequency
Fpass = 1;           % Passband Frequency
Astop = 120;         % Stopband Attenuation (dB)
Apass = 1;           % Passband Ripple (dB)
match = 'stopband';  % Band to match exactly

% Construct an FDESIGN object and call its BUTTER method.
h  = fdesign.highpass(Fstop, Fpass, Astop, Apass, Fs);
Hd2 = design(h, 'butter', 'MatchExactly', match);

Hd = dfilt.cascade(Hd2,Hd2);

% [EOF]