cnc_trellis.m

这是一个vblast程序

% function [nxt_s,nxt_o,nxt_s_c1,nxt_s_c2,lst_s_c1,lst_s_c2] = cnc_trellis(code_g);
function [nxt_s,nxt_o] = cnc_trellis(code_g);
% 只适应于 1/2 码率的二进制非递归卷积码

[n,K] = size(code_g);
M=2^(K-1);
code_g_oct=zeros(1,2);
%这一步的目的：将二进制转换成八进制
%这一步的意义：poly2trellis的需要
for j1=1:2
    sum_dec=0;
    for i1=1:K
        sum_dec=sum_dec+code_g(j1,K+1-i1).*(2^(i1-1));  %二进制转换成十进制
    end
    code_g_oct(1,j1)=str2num(dec2base(sum_dec,8));    %十进制转换成八进制
end


nxt_s_c1=-1*ones(M,2);
nxt_s_c2=-1*ones(M,2);


trellis=poly2trellis(K,code_g_oct);
nxt_o_dec=trellis.outputs;
nxt_s=trellis.nextStates;
nxt_o_0=nxt_o_dec(:,1);
nxt_o_1=nxt_o_dec(:,2);
temp1_0=de2bi(nxt_o_0,2,'left-msb');
temp1_1=de2bi(nxt_o_1,2,'left-msb');
nxt_o(:,1:2)=temp1_0;
nxt_o(:,3:4)=temp1_1;

% temp1_0_c1=temp1_0(:,1);
% temp1_1_c1=temp1_1(:,1);
% nxt_s_0=nxt_s(:,1);
% nxt_s_1=nxt_s(:,2);
% Index1=find(temp1_0_c1==0);
% Index2=find(temp1_1_c1==0);
% nxt_s_c1(Index1,1)=nxt_s_0(Index1);
% nxt_s_c1(Index2,1)=nxt_s_1(Index2);
% Index1=find(temp1_0_c1==1);
% Index2=find(temp1_1_c1==1);
% nxt_s_c1(Index1,2)=nxt_s_0(Index1);
% nxt_s_c1(Index2,2)=nxt_s_1(Index2);
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% temp1_0_c2=temp1_0(:,2);
% temp1_1_c2=temp1_1(:,2);
% Index1=find(temp1_0_c2==0);
% Index2=find(temp1_1_c2==0);
% nxt_s_c2(Index1,1)=nxt_s_0(Index1);
% nxt_s_c2(Index2,1)=nxt_s_1(Index2);
% Index1=find(temp1_0_c2==1);
% Index2=find(temp1_1_c2==1);
% nxt_s_c2(Index1,2)=nxt_s_0(Index1);
% nxt_s_c2(Index2,2)=nxt_s_1(Index2);
% 
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 
% [value,lst_s_c1]=sort(nxt_s_c1);
% lst_s_c1=lst_s_c1-1;
% [value,lst_s_c2]=sort(nxt_s_c2);
% lst_s_c2=lst_s_c2-1;