turbo_encode.m

turbo码BPSK仿真

% x ------信息源0 1 行向量
% g ------生成矩阵   g= 1 1 1
%                       1 0 1   等
%    [n,k]=size(g)
%    m=k-1
% Alpha ---交织器   (交织器大小为 length(x)+m)
% puncture----是否凿孔 0--凿孔，码率1/2
%                      1--不凿孔，码率1/3
% 程序最终输出en_output 为1 0行向量

function x_code_msg = turbo_encode( x_msg,g,Alpha,puncture)
[n,k] = size(g); 
m = k - 1;
L_info = length(x_msg); 
L_total = L_info + m;  


input = x_msg;
output1 = rsc_encode(g,input,1);


y(1,:) = output1(1:2:2*L_total);
y(2,:) = output1(2:2:2*L_total);


for i = 1:L_total
   input1(1,i) = y(1,Alpha(i)); 
end
output2 = rsc_encode(g, input1(1,1:L_total), -1 );
y(3,:) = output2(2:2:2*L_total);



if puncture > 0		
   for i = 1:L_total
       for j = 1:3
           en_output(1,3*(i-1)+j) = y(j,i);
       end
   end
else		
   for i=1:L_total
       en_output(1,n*(i-1)+1) = y(1,i);
       if rem(i,2)
      
          en_output(1,n*i) = y(2,i);
       else
     
          en_output(1,n*i) = y(3,i);
       end 
    end  
end
x_code_msg=en_output;