zmapping.m

the file contain many matlab signal source code and many example .

function [bz,az]=zmapping(bZ,aZ,Nz,Dz)
% Frequency band Transformation from Z-domain to z-domain 
% --------------------------
% [bz,az]=zmapping(bZ,aZ,Nz,Dz)
% performs:
%   b(z)       b(Z) |
%  ------ = --------|       N(z)
%   a(z)       a(Z)  |  Z=-----
%                            |     D(z)
bzord=(length(bZ)-1)*(length(Nz)-1);
azord=(length(aZ)-1)*(length(Dz)-1);
bz=zeros(1,bzord+1);
for k=0:bzord
    pln=[1];
    for l=0:k-1;
        pln=conv(pln,Nz);
    end
    pld=[1];
    for l=0:bzord-k-1
        pld=conv(pld,Dz);
    end
    bz=bz+bZ(k+1)*conv(pln,pld);
end
az=zeros(1,azord+1);
for k=0:azord
    pln=[1];
    for l=0:k-1
        pln=conv(pln,Nz);
    end
    pld=[1];
    for l=0:azord-k-1
        pld=conv(pld,Dz);
    end
    az=az+aZ(k+1)*conv(pln,pld);
end
az1=az(1);az=az/az1;bz=bz/az1;