www.pudn.com > nsct_toolbox.rar > ldfilter.m, change:2003-11-05,size:662b


function f = ldfilter(fname) 
% LDFILTER	Generate filter for the ladder structure network 
% 
%	f = ldfilter(fname) 
% 
% Input: 
%	fname:  Available 'fname' are: 
%           'pkvaN': length N filter from Phoong, Kim, Vaidyanathan and Ansari 
 
switch fname 
    case {'pkva12', 'pkva'} 
        v = [0.6300   -0.1930    0.0972   -0.0526    0.0272   -0.0144]; 
         
    case {'pkva8'} 
        v = [0.6302   -0.1924    0.0930   -0.0403]; 
         
    case {'pkva6'} 
        v = [0.6261   -0.1794    0.0688]; 
         
    otherwise 
        error('Unrecognized ladder structure filter name'); 
end 
 
% Symmetric impulse response 
f = [v(end:-1:1), v];