pr7_35.m

Spread Spectrum and CDMA Principles and Applications 书籍和代码

%Problem 7.35;
%Ross-Taylor-Paavola-Ipatov oversaturation;

clear all;
H=[1,1,1,1;-1,-1,1,1;1,-1,1,-1;1,-1,-1,1]; %initial hadamard matrix;
l=input('input l='); %inputting power of 4 in signature length;
N=4^l; %signature length;
H1=H; %initializing Kronecker degree;
for k=1:l-1
    H1=kron(H1,H);
end; %primary signatures ready;
H1=H1/(2^l); %normalization;
Sp=[]; Spk=H1; n=N; %initializing recurrency of supplementary signatures;
for k=1:l
    n=n/4; 
    Sp2=[]; %template of supplementary signatures;
    for s=0:n-1
        a=Spk(4*s+1,:)+Spk(4*s+2,:)+Spk(4*s+3,:)+Spk(4*s+4,:);
        Sp2=[Sp2;a];
    end; %finish s-th supplementary signatures of k-th level
    Spk=Sp2/2; %normalization;
    Sp=[Sp;Spk]; %finish all supplementary signatures on k-th level;
end; %finish all supplementary signatures;
S=[H1;Sp]'; %the complete signature matrix, signatures are columns;
Snn=(2^l)*S; %non-normalized signatures;