code_block_generation.m

i hope use every file i put here to evry one and thank >

function [code_block,f_comp] = code_block_generation(ofdm_block)

global H

% get AMP
s = get(H.edit18,'String');
AMP = st2de(s);
AMP = round(AMP);

% get B
s = get(H.edit21,'String');
B = st2de(s);
B = round(B);

s = get(H.edit12,'String');
M = st2de(s);
M = round(M);

% convert ofdm_block into frequency domain
% this information will be used to produce binary code
f = fft(ofdm_block);

f_real = real(f);
f_imag = imag(f);

% create dc(direct current) and fc(carrier frequency) information
dc = 1;
fc = length(f) + 1;

% fix phase shift by comparing phase shift of adjacent frequencies to
% our frequencies
if get(H.checkbox1,'Value') == 1
    for k = 1:4,
        [mag1,phase_change] = r2p(f(dc + (k * M) + B));
        
        mag_factor = mag1 / (AMP / 3);
   
        [mag2,phase] = r2p(f(dc + (k * M)));
   
        new_mag = mag2 / mag_factor;
   
        new_phase = phase - phase_change;
   
        f(dc + (k * M)) = p2r(new_mag,new_phase);
        f(fc - (k * M)) = conj(f(dc + (k * M)));
   
        f(dc + (k * M) + B) = 0;
        f(fc - (k * M) - B) = 0;
    end
end

f_comp = f;

% initialize code_block and index
code_block = [0 0 0 0 0 0 0 0];
index = 1;

% loop to produce code from ofdm_block
for n = 1:4;
   
   % find real and imaginary parts of frequency components (left is sideband of dc, right is sideband of fc)
   real_f = real(f(dc + (n * M)));
   %right_real = real(f(fc - (n * M)));
   imag_f = imag(f(dc + (n * M)));
   %right_imag = imag(f(fc - (n * M)));
   
   % locate frequency spikes representing sine wave
   if real_f > (AMP - 100) & real_f < (AMP + 100) & imag_f > (-AMP - 100) & imag_f < (-AMP + 100)
      
      % sine wave represents [0 0]
      code_block(index:index + 1) = [0 0];
   end
   
   % locate frequency spikes representing -sine wave
   if real_f > (-AMP - 100) & real_f < (-AMP + 100) & imag_f > (-AMP - 100) & imag_f < (-AMP + 100) 
      
      % -sine wave represents [0 1]
      code_block(index:index + 1) = [0 1];
   end
   
   % locate frequency spikes representing cosine wave
   if real_f > (-AMP - 100) & real_f < (-AMP + 100) & imag_f > (AMP - 100) & imag_f < (AMP + 100) 
      
      % cosine wave represents [1 0]
      code_block(index:index + 1) = [1 0];
   end
   
   % locate frequency spikes representing -cosine wave
   if real_f > (AMP - 100) & real_f < (AMP + 100) & imag_f > (AMP - 100) & imag_f < (AMP + 100)
      
      % -cosine wave represents [1 1]
      code_block(index:index + 1) = [1 1];
   end
   
   % update code index
   index = index + 2;
end