%close all;clear all; more off; set (0,"defaultaxesfontname","Helvetica")
tic

% 1. case of ishort datasets
% d=dir('./150719_gn3s_ishort.bin');    % case of ishort
%  x=read_short_binary(d(1).name,5e5);x=x(1:2:end)+i*x(2:2:end);     % ishort

% 2. case of interleaved char datasets
% d=dir('./150719_gn3s_ichar.bin');     % case of interleaved char
% f=fopen(d(1).name);x=fread(f,5e5,'int8');x=i*x(1:2:end)+x(2:2:end); % char
% notice that since I put imag on top, the odd values are imag and even
% are real

% 3. case of 1-bit datasets
d=dir('output_bit.bin');
f=fopen('output_bit.bin');x=fread(f,5e5,'ubit1');
k=find(x==0);x(k)=-1;x=x(1:2:end)+i*x(2:2:end);

  fs=8.183800; % MHz
  freq0=[28.3e3:500:48.4e3];
  
  x=x(1:2e5);
  time=[0:1/fs/1e6:length(x)/fs/1e6]';time=time(1:end-1);
  for m=[1:31]
   a=cacode(m,fs/1.023); a=a-mean(a);
   l=1;
   m
   for freq=freq0               % run through possible frequency offsets
    mysine=exp(j*2*pi*(freq)*time); 
    xx=x.*mysine;                     % frequency shift the signal
    xx=xx-mean(xx);
    [u(l,m),v(l,m)]=max(abs(xcorr(a,xx))); % check for cross correlation max.
    l=l+1;
   end
  end
 % figure
  imagesc([1:31],freq0/1e3,abs(u))
  xlabel('PRN')
  ylabel('frequency (kHz)')
  title(d(1).name)
  eval(['print -depsc ',d(1).name,'.eps']);
%plot(freq0,abs(u(:,m)))