% Theoretical output for comparison with gpstk acquisition program.

G1 = [1,1,1,1,1,1,1,1,1,1];
G2 = [1,1,1,1,1,1,1,1,1,1];
PRN = zeros(1,2046);
count = 1;
while count <= 2046
  newBit1 = xor(G1(3),G1(10));
  newBit2 = xor(G2(2),G2(3));
  newBit2 = xor(newBit2,G2(6));
  newBit2 = xor(newBit2,G2(8));
  newBit2 = xor(newBit2,G2(9));
  newBit2 = xor(newBit2,G2(10));
  G2i = xor(G2(5),G2(9));
  PRN(count) = xor(G2i,G1(10));
  G1 = [newBit1 G1(1:9)];
  G2 = [newBit2 G2(1:9)];
  count = count + 1;  
  end
PRNtwo = (PRN == 0)*(1)+(PRN==1)*(-1); %changed to -1 and 1 from binary

x1 = PRNtwo([(end-173:end) (1:end-173)]);
 
for n = 1:1023
  sum = 0;
  for k = 1:1023
    sum = sum + PRNtwo(k) * x1(k+n);
  end
  RX(n) = (abs(sum)/1023)*130;        %/1023;  % divide to get normalized graph
end
n = 1:1023;
plot(n,RX,'r');