odd_even_interleaver.m

通信中常用的卷积码信道译码源码程序

function alpha_rsc = odd_even_interleaver(DLength,TerminateF,NEncoders,m);

%------------------------------------------------------------------------------
% Create odd-even interleaver of length 'DLength'
%
% Format:
% -------
%
% alpha_rsc = odd_even_interleaver(DLength, TerminateF, NEncoders, m)
% 
% Author: MVe
% Date:   05.07.2002
%------------------------------------------------------------------------------

rand('state',sum(100*clock));

if TerminateF
  index_odd = [1:2:DLength+m];
  index_even = [2:2:DLength+m];
else 
  index_odd = [1:2:DLength];
  index_even = [2:2:DLength];
end % if TerminateF
Lodd = length(index_odd);
Leven = length(index_even);
for i1 = 1:NEncoders-1
  [dummy, alpha_tmp1(1,:)] = sort(rand(1,Lodd));
  [dummy, alpha_tmp2(1,:)] = sort(rand(1,Leven));
  if (Lodd>Leven)
    alpha_rsc(i1,:) = ...
	reshape([index_odd(alpha_tmp1);index_even(alpha_tmp2), 0], ...
		1,2*Lodd);
  else
    alpha_rsc(i1,:) = ...
	reshape([index_odd(alpha_tmp1);index_even(alpha_tmp2)],1,2*Lodd);
  end % if (Lodd>Leven)	
end % for i1 = 1:NEncoders-1