Please tell me is this correct.. To add precoding block in between interleaver and modulator in OFDM? Serial to parallel transmission in OFDM?

Question

Koshy 2015-9-15

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/243163-please-tell-me-is-this-correct-to-add-precoding-block-in-between-interleaver-and-modulator-in-ofdm

编辑： Walter Roberson 2015-9-15

This is the code. I have tried to do linear precoding...

%input
msg = round(rand(1,nBitPerSym*nSym));
% trellis 
trel = poly2trellis(3,[7 5]);
% % % convolution encoder
code = convenc(message,trel);
% state 
st2 = 4831;
inter1 = randintrlv(code,st2);
%precoding
N=nSym ;
x = zeros(2,N);
x1 = reshape(inter1,2,length(inter1)/2); 
x2 =[conj(double(x1(2,:))); conj(double(x1(1,:)))]; 
x=[x1;x2]
[rowSize, colSize] = size(x);
% Converting two rows into one concatenated row. 
p_Data = reshape(x,rowSize*colSize,1);
p_Data = sqrt(2) * p_Data;
y1=inter1./p_Data';
Then this y1 is QAM modulated and further OFDM is done...
Please tell me whether this is correct
Also  serial to parallel conversion in ofdm is 
for ii = 1:length(EbN0dB) 
      % Transmitter 
     %    MODULATE 
      h1 = modem.qammod(16);
      qm1 = modulate(h1, inter);
     %ipBit1 = inter1(1:length(msg)) ; 
  %    MODULATE 
     %ipMod1 = 2*ipBit1-1; 
     h2 = modem.qammod(16);
      qm = modulate(h2, inter1);
  % %    combine
     ipMod1=qm;
     ipMod = reshape(ipMod1,nBitPerSym,2*nSym).'; % group into multiple streams
  .
  .
  end