encoderm.m

迭代多用户检测的MATLAB详细实现,非常全面,主要基于Vincent Poor和王晓东提出的算法实现,绝对的好东西.

function en_output = encoderm( x, g, alpha, puncture )
% Copyright Nov. 1998 Yufei Wu
% MPRG lab, Virginia Tech.
% for academic use only

% uses interleaver map 'alpha'
% if puncture = 1, unpunctured, produces a rate 1/3 output of fixed length
% if puncture = 0, punctured, produces a rate 1/2 output 
% multiplexer chooses odd check bits from RSC1 
% and even check bits from RSC2

% determine the constraint length (K), memory (m) 
% and number of information bits plus tail bits.

[n,K] = size(g); 
m = K - 1;
L_info = length(x); 
L_total = L_info + m;  

% generate the codeword corresponding to the 1st RSC coder
% end = 1, perfectly terminated;
input = x;
en_output = rsc_encode(g,input,1);

% make a matrix with first row corresponing to info sequence
% second row corresponsing to RSC #1's check bits.
% third row corresponsing to RSC #2's check bits.


% interleave input to second encoder


% paralell to serial multiplex to get output vector
% puncture = 0: rate increase from 1/3 to 1/2;
% puncture = 1; unpunctured, rate = 1/3;



% antipodal modulation: +1/-1
en_output = 2 * en_output - ones(size(en_output));