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%Matlab script for Illustrative Problem 9.5 产生GOLD序列 
echo on 
%First determine the maximal length shift-register sequences.首先确定最大长度移位寄存器序列 
%Assume the initial shift-register content as '00001'.假设移位寄存器的初始态是00001 
connections1=[1 0 1 0 0]; 
connections2=[1 1 1 0 1]; 
sequence1=ss_mlsrs(connections1); 
sequence2=ss_mlsrs(connections2); 
%Cyclically shift the second sequence and add it to the first one.对第二个序列循环移位，并最后加到第一个序列里 
L=2^length(connections1)-1; 
for shift_amount=0:L-1, 
    temp=[sequence2(shift_amount+1:L) sequence2(1:shift_amount)];  %对第二个序列循环移位 
    gold_seq(shift_amount+1,:)=(sequence1+temp)-floor((sequence1+temp)./2).*2; %循环后与第一个序列按模2相加 
    echo off; 
end; 
echo on; 
%Find the max value of the cross-correlation for these sequences.找到这些序列之间互相关函数最大值 
max_cross_corr=0; 
for i=1:L-1, 
    for j=i+1:L, 
        %equivalent sequences 等价的双极性序列 
        c1=2*gold_seq(i,:)-1; 
        c2=2*gold_seq(j,:)-1; 
        for m=0:L-1, 
            shifted_c2=[c2(m+1:L) c2(1:m)]; 
            corr=abs(sum(c1.*shifted_c2));%存放gold序列的互相关函数 
            if (corr>max_cross_corr), 
                max_cross_corr=corr;  %记录互相关函数的最大值 
            end; 
            echo off; 
        end; 
    end; 
end; 
%Note that max_cross_correlation turns out to be 9 in this example.