Rename 'decoder' to 'blocks'.

git-svn-id: http://op25.osmocom.org/svn/trunk@283 65a5c917-d112-43f1-993d-58c26a4786be

1 files changed, 113 insertions, 0 deletions

diff --git a/blocks/src/lib/op25_fsk4_demod_ff.h b/blocks/src/lib/op25_fsk4_demod_ff.h
new file mode 100644
index 0000000..903b479
--- /dev/null
+++ b/blocks/src/lib/op25_fsk4_demod_ff.h
@@ -0,0 +1,113 @@
+/* -*- C++ -*- */
+
+/*
+ * Copyright 2006, 2007 Frank (Radio Rausch)
+ * Copyright 2011 Steve Glass
+ * 
+ * This file is part of OP25.
+ * 
+ * OP25 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.
+ * 
+ * OP25 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 OP25; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 51 Franklin Street, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_OP25_FSK4_DEMOD_FF_H
+#define INCLUDED_OP25_FSK4_DEMOD_FF_H
+
+#include <gr_block.h>
+#include <gr_msg_queue.h>
+
+#include <boost/scoped_array.hpp>
+
+typedef boost::shared_ptr<class op25_fsk4_demod_ff> op25_fsk4_demod_ff_sptr;
+
+op25_fsk4_demod_ff_sptr op25_make_fsk4_demod_ff(gr_msg_queue_sptr queue, float sample_rate, float symbol_rate);
+
+/**
+ * op25_fsk4_demod_ff is a GNU Radio block for demodulating APCO P25
+ * CF4M signals. This class expects its input to consist of a 4 level
+ * FSK modulated baseband signal. It produces a stream of symbols.
+ *
+ * All inputs are post FM demodulator and symbol shaping filter data
+ * is normalized before being sent to this block so these parameters
+ * should not need adjusting even when working on different signals.
+ *
+ * Nominal levels are -3, -1, +1, and +3.
+ */
+class op25_fsk4_demod_ff : public gr_block
+{
+public:
+
+   /**
+    * op25_fsk4_demod_ff (virtual) destructor.
+    */
+   virtual ~op25_fsk4_demod_ff();
+
+   /**
+    * Estimate nof_input_items_reqd for a given nof_output_items.
+    */
+   virtual void forecast(int noutput_items, gr_vector_int &inputs_required);
+
+   /**
+    * Process baseband into symbols.
+    */
+   virtual int general_work(int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items);
+
+private:
+
+   /**
+    * Expose class to public ctor. Create a new instance of
+    * op25_fsk4_demod_ff and wrap it in a shared_ptr. This is
+    * effectively the public constructor.
+    */
+   friend op25_fsk4_demod_ff_sptr op25_make_fsk4_demod_ff(gr_msg_queue_sptr queue, float sample_rate, float symbol_rate);
+
+   /**
+    * op25_fsk4_demod_ff private constructor.
+    */
+   op25_fsk4_demod_ff(gr_msg_queue_sptr queue, float sample_rate, float symbol_rate);
+
+   /**
+    * Called when we want the input frequency to be adjusted.
+    */
+   void send_frequency_correction();
+
+   /**
+    * Tracking loop.
+    */
+   bool tracking_loop_mmse(float input, float *output);
+
+private:
+
+   const float d_block_rate;
+
+   boost::scoped_array<float> d_history;
+
+   size_t d_history_last;
+
+   gr_msg_queue_sptr d_queue;
+
+   double d_symbol_clock;
+
+   double d_symbol_spread;
+
+   const float d_symbol_time;
+
+   double fine_frequency_correction;
+
+   double coarse_frequency_correction;
+
+};
+
+#endif /* INCLUDED_OP25_FSK4_DEMOD_FF_H */