From 32b853134a47904f37586c7cb097c1cdb5e6da80 Mon Sep 17 00:00:00 2001
From: Manolis Surligas <surligas@csd.uoc.gr>
Date: Tue, 22 Nov 2016 11:49:42 +0200
Subject: [PATCH] Fix Doppler shift direction (#43)

---
 lib/coarse_doppler_correction_cc_impl.cc | 3 ++-
 lib/doppler_correction_cc_impl.cc        | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/coarse_doppler_correction_cc_impl.cc b/lib/coarse_doppler_correction_cc_impl.cc
index 025fbc9..345df41 100644
--- a/lib/coarse_doppler_correction_cc_impl.cc
+++ b/lib/coarse_doppler_correction_cc_impl.cc
@@ -25,6 +25,7 @@
 #include <gnuradio/io_signature.h>
 #include "coarse_doppler_correction_cc_impl.h"
 #include <volk/volk.h>
+#include <satnogs/log.h>
 
 namespace gr
 {
@@ -86,7 +87,7 @@ namespace gr
       boost::mutex::scoped_lock lock (d_mutex);
       double new_freq;
       new_freq = pmt::to_double (msg);
-      d_freq_diff = d_target_freq - new_freq;
+      d_freq_diff = new_freq - d_target_freq;
       d_nco.set_freq ((2 * M_PI * (-d_freq_diff)) / d_samp_rate);
     }
 
diff --git a/lib/doppler_correction_cc_impl.cc b/lib/doppler_correction_cc_impl.cc
index 2d1525b..36aebf9 100644
--- a/lib/doppler_correction_cc_impl.cc
+++ b/lib/doppler_correction_cc_impl.cc
@@ -102,7 +102,7 @@ namespace gr
       boost::mutex::scoped_lock lock (d_mutex);
       double new_freq;
       new_freq = pmt::to_double (msg);
-      d_freq_diff = d_target_freq - new_freq;
+      d_freq_diff = new_freq - d_target_freq;
       if (!d_have_est) {
 	d_freq_est_num++;
 	d_doppler_freqs.push_back (