Ressurected old frequency correction function
diff --git a/lib/receiver/receiver_impl.cc b/lib/receiver/receiver_impl.cc
index f43f6e0..e69183f 100644
--- a/lib/receiver/receiver_impl.cc
+++ b/lib/receiver/receiver_impl.cc
@@ -26,7 +26,6 @@
#include <gnuradio/io_signature.h>
#include <gnuradio/math.h>
-#include <volk/volk.h>
#include <math.h>
#include <boost/circular_buffer.hpp>
#include <algorithm>
@@ -35,7 +34,6 @@
#include <viterbi_detector.h>
#include <string.h>
#include <iostream>
-#include <time.h> //!!!
//#include <iomanip>
#include <boost/scoped_ptr.hpp>
@@ -534,44 +532,22 @@
return result;
}
-double receiver_impl::estim_freq_norm(const gr_complex * input, unsigned first_sample, unsigned last_sample) //another frequency estimator
-{
-
- unsigned ii;
-
- double sum = 0;
-
- for (ii = first_sample; ii < last_sample-1; ii++)
- {
- sum += fast_atan2f(input[ii+1] * conj(input[ii]));
- }
- int N = last_sample-1-first_sample;
- return sum/(2*M_PI)/N * d_OSR;
-}
-
double receiver_impl::compute_freq_offset(const gr_complex * input, unsigned first_sample, unsigned last_sample)
{
- float freq_norm = estim_freq_norm(input, first_sample, last_sample);
- float freq_offset = (freq_norm - 0.25) * 1625000.0/6.0;
+ double phase_sum = 0;
+ unsigned ii;
+
+ for (ii = first_sample; ii < last_sample; ii++)
+ {
+ double phase_diff = compute_phase_diff(input[ii], input[ii-1]) - (M_PI / 2) / d_OSR;
+ phase_sum += phase_diff;
+ }
+
+ double phase_offset = phase_sum / (last_sample - first_sample);
+ double freq_offset = phase_offset * 1625000.0 / (12.0 * M_PI);
return freq_offset;
}
-//double receiver_impl::compute_freq_offset(const gr_complex * input, unsigned first_sample, unsigned last_sample)
-//{
-// double phase_sum = 0;
-// unsigned ii;
-
-// for (ii = first_sample; ii < last_sample; ii++)
-// {
-// double phase_diff = compute_phase_diff(input[ii], input[ii-1]) - (M_PI / 2) / d_OSR;
-// phase_sum += phase_diff;
-// }
-
-// double phase_offset = phase_sum / (last_sample - first_sample);
-// double freq_offset = phase_offset * 1625000.0 / (12.0 * M_PI);
-// return freq_offset;
-//}
-
inline float receiver_impl::compute_phase_diff(gr_complex val1, gr_complex val2)
{
gr_complex conjprod = val1 * conj(val2);
diff --git a/lib/receiver/receiver_impl.h b/lib/receiver/receiver_impl.h
index 251cf55..6074dd5 100644
--- a/lib/receiver/receiver_impl.h
+++ b/lib/receiver/receiver_impl.h
@@ -108,8 +108,6 @@
* @return true if frequency offset was faound
*/
double compute_freq_offset(const gr_complex * input, unsigned first_sample, unsigned last_sample);
-
- double estim_freq_norm(const gr_complex * input, unsigned first_sample, unsigned last_sample); //normalized frequency estimator
/** Computes angle between two complex numbers
*
* @param val1 first complex number