golaydecode.m

以bpsk为平台的golay编码解码功能,及其误码曲线分析

function [out]=golaydecode(demodata1)
B=[1 1 0 1 1 1 0 0 0 1 0 1;    
   1 0 1 1 1 0 0 0 1 0 1 1;    
   0 1 1 1 0 0 0 1 0 1 1 1;   
   1 1 1 0 0 0 1 0 1 1 0 1;   
   1 1 0 0 0 1 0 1 1 0 1 1;   
   1 0 0 0 1 0 1 1 0 1 1 1;   
   0 0 0 1 0 1 1 0 1 1 1 1;   
   0 0 1 0 1 1 0 1 1 1 0 1;   
   0 1 0 1 1 0 1 1 1 0 0 1;   
   1 0 1 1 0 1 1 1 0 0 0 1;   
   0 1 1 0 1 1 1 0 0 0 1 1;   
   1 1 1 1 1 1 1 1 1 1 1 0];
H=[eye(12);B];  
s=demodata1*H-floor((demodata1*H)./2).*2; %矩阵乘中，是模2加。
u=zeros(1,24);
weight1=nnz(s);  %s的汉明重量
if weight1<=3,    %Case 1
    u=[s,zeros(1,12)];
else
    for ii=1:12,
        weight2(ii)=nnz(B(ii,:)+s); %weight2(ii)记录 B(ii,:)+s 的重量
    end
    wnum=find(weight2<=2); % 重量<=2的下标值，wnum对应B的行标
    if ~isempty(wnum), % Case 2 
        ematrix=[zeros(1,wnum(1)-1),1,zeros(1,12-wnum(1))];%取满足条件的第一个B的行数
        u=[s+B(wnum(1),:),ematrix];
    else
        s2=s*B-floor((s*B)./2).*2;
        weight3=nnz(s2);
        if weight3<=3,  % Case 3
            u=[zeros(1,12),s2];
        else
            for ii1=1:12,
                weight4(ii1)=nnz(B(ii1,:)+s2);
            end
            wnum2=find(weight4<=2);
            if ~isempty(wnum2),  % Case 4
                ematrix2=[zeros(1,wnum2(1)-1),1,zeros(1,12-wnum2(1))];
                u=[ematrix2,s2+B(wnum2(1),:)];
            end
        end
    end
end
out=demodata1+u-floor((demodata1+u)./2).*2;% 模2加