ldpc_linetime_encode.m

用Matlab实现的LDPC编码程序

%function y=ldpc_linetime_encode(x,H,inv_phi1,g);
%WITH THE PARAMETER PROCEDUARE WE CAN GET H,inv_phi1,GAP;
%H IS PARITY CHECK MATRIX,g IS GAP BETWEEN H AND REAL DOWNDIAGNAL 
%MATRIX DISTANCE,INV_PHI1 SHOULD BE INVERTIBLE;
%x IS A INPUT MESSAGE BIT VECTOR,y IS A OUTPUT CODEWORD;
%rand('state',123);

%load regularHmatrix_N20_K15_j3_k4.mat%%HforOFDM222.mat%
%H=Hsparse;
%[m,n]=size(H);flag=0;
%gap=max(find(H(:,1)));g=gap-1;
%load invmodifield inv_phi1

 load HmodifiedforOFDM H;
   
% load gmodifield g
   

[m,n]=size(H);
%gap=max(find(H(:,1)));g=gap-1;
%x=[0 1 0 1 0];
x=(sign(rand(1,n-m)-0.5)+1)/2;
%x=sparse(randint(1,n-m));
A=H(1:m-g,1:n-m);
B=H(1:m-g,n-m+1:n-m+g);
C=H(m-g+1:m,1:n-m);
T=H(1:m-g,n-m+g+1:n);
E=H(m-g+1:m,n-m+g+1:n);
p1=mod(A*x',2);
p1=mod(T\p1,2);
p1=mod(inv_phi1'*(E*p1+C*x'),2);%p1=mod(inv_phi1*p1,2);
p2=mod(A*x'+B*p1,2);
p2=mod(T\p2,2);
y=[x,p1',p2'];%CHECK COMMAND:sparse(mod(H*y',2))