Added timestamping of bursts in the gsm receiver
diff --git a/lib/receiver/time_sample_ref.cc b/lib/receiver/time_sample_ref.cc
new file mode 100644
index 0000000..0cf85ed
--- /dev/null
+++ b/lib/receiver/time_sample_ref.cc
@@ -0,0 +1,60 @@
+/* -*- c++ -*- */
+/*
+ * @file
+ * @author (C) 2017 by Piotr Krysik <ptrkrysik@gmail.com>
+ * @section LICENSE
+ *
+ * Gr-gsm is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ *
+ * Gr-gsm is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with gr-gsm; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include <math.h>
+#include "time_sample_ref.h"
+
+namespace gr {
+ namespace gsm {
+ time_sample_ref::time_sample_ref(double samp_rate): d_samp_rate(samp_rate)
+ {
+ }
+
+ time_sample_ref::~time_sample_ref()
+ {
+ }
+
+ void time_sample_ref::update(time_spec_t last_rx_time, uint64_t current_start_offset)
+ {
+ d_last_rx_time = last_rx_time;
+ d_current_start_offset = current_start_offset;
+ }
+
+ time_spec_t time_sample_ref::offset_to_time(uint64_t offset)
+ {
+ uint64_t samples_from_last_rx_time = offset - d_current_start_offset;
+ time_spec_t time = time_spec_t(static_cast<double>(samples_from_last_rx_time)/d_samp_rate) + d_last_rx_time;
+
+ return time;
+ }
+
+ uint64_t time_sample_ref::time_to_offset(time_spec_t time)
+ {
+ double samples_since_last_rx_time_tag = (time-d_last_rx_time).get_real_secs()*d_samp_rate;
+// double fractional_part = round(samples_since_last_rx_time_tag) - samples_since_last_rx_time_tag;
+ uint64_t offset = static_cast<uint64_t>(round(samples_since_last_rx_time_tag)) + d_current_start_offset;
+
+ return offset;
+ }
+ } // namespace gsm
+} // namespace gr
+