digital: converted over constellation and related blocks.

Possibly still a work-in-progress. Need to convert over some more before QA can be run.
author: Tom Rondeau <trondeau@vt.edu> 2012-08-11 11:04:03 -0400
committer: Tom Rondeau <trondeau@vt.edu> 2012-08-11 11:04:03 -0400
commit: a6e56683cf74054fad6774138bea9f844c76be09 (patch)
tree: 1749031397ac4ebdc117b05a753c82976e8aca62 /gr-digital/include/digital
parent: af0a5780201c71c8f2d682cdab2274942e5771d5 (diff)
4 files changed, 568 insertions, 3 deletions
diff --git a/gr-digital/include/digital/CMakeLists.txt b/gr-digital/include/digital/CMakeLists.txt
index 0f009f1fa8..0fdc0dd008 100644
--- a/gr-digital/include/digital/CMakeLists.txt
+++ b/gr-digital/include/digital/CMakeLists.txt
@@ -84,9 +84,9 @@ install(FILES
     clock_recovery_mm_ff.h
     cma_equalizer_cc.h
 #    cpmmod_bc.h
-#    constellation.h
-#    constellation_receiver_cb.h
-#    constellation_decoder_cb.h
+    constellation.h
+    constellation_receiver_cb.h
+    constellation_decoder_cb.h
 #    correlate_access_code_bb.h
 #    correlate_access_code_tag_bb.h
 #    costas_loop_cc.h
diff --git a/gr-digital/include/digital/constellation.h b/gr-digital/include/digital/constellation.h
new file mode 100644
index 0000000000..49da76f70d
--- /dev/null
+++ b/gr-digital/include/digital/constellation.h
@@ -0,0 +1,417 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2010-2012 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio 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.
+ *
+ * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_DIGITAL_CONSTELLATION_H
+#define	INCLUDED_DIGITAL_CONSTELLATION_H
+
+#include <digital/api.h>
+#include <digital_metric_type.h>
+#include <boost/enable_shared_from_this.hpp>
+#include <gr_complex.h>
+#include <vector>
+
+namespace gr {
+  namespace digital {
+
+    /************************************************************/
+    /* constellation                                            */
+    /*                                                          */
+    /* Base class defining interface.                           */
+    /************************************************************/
+    
+    class constellation;
+    typedef boost::shared_ptr<constellation> constellation_sptr;
+
+    /*!
+     * \brief An abstracted constellation object
+     * \ingroup digital
+     *
+     * The constellation objects hold the necessary information to pass
+     * around constellation information for modulators and
+     * demodulators. These objects contain the mapping between the bits
+     * and the constellation points used to represent them as well as
+     * methods for slicing the symbol space. Various implementations are
+     * possible for efficiency and ease of use.
+     *
+     * Standard constellations (BPSK, QPSK, QAM, etc) can be inherited
+     * from this class and overloaded to perform optimized slicing and
+     * constellation mappings.
+     */
+    class DIGITAL_API constellation
+      : public boost::enable_shared_from_this<constellation>
+    {
+    public:
+      constellation(std::vector<gr_complex> constell,
+		    std::vector<unsigned int> pre_diff_code,
+		    unsigned int rotational_symmetry,
+		    unsigned int dimensionality);
+      constellation();
+      ~constellation();
+
+      //! Returns the constellation points for a symbol value
+      void map_to_points(unsigned int value, gr_complex *points);
+      std::vector<gr_complex> map_to_points_v(unsigned int value);
+
+      //! Returns the constellation point that matches best.
+      virtual unsigned int decision_maker(const gr_complex *sample) = 0;
+      //! Takes a vector rather than a pointer.  Better for SWIG wrapping.
+      unsigned int decision_maker_v(std::vector<gr_complex> sample);
+      //! Also calculates the phase error.
+      unsigned int decision_maker_pe(const gr_complex *sample, float *phase_error);
+      //! Calculates distance.
+      //unsigned int decision_maker_e(const gr_complex *sample, float *error);
+  
+      //! Calculates metrics for all points in the constellation.
+      //! For use with the viterbi algorithm.
+      virtual void calc_metric(const gr_complex *sample, float *metric, trellis_metric_type_t type);
+      virtual void calc_euclidean_metric(const gr_complex *sample, float *metric);
+      virtual void calc_hard_symbol_metric(const gr_complex *sample, float *metric);
+  
+      //! Returns the set of points in this constellation.
+      std::vector<gr_complex> points() { return d_constellation;}
+      //! Returns the vector of points in this constellation.
+      //! Raise error if dimensionality is not one.
+      std::vector<gr_complex> s_points();
+      //! Returns a vector of vectors of points.
+      std::vector<std::vector<gr_complex> > v_points();
+      //! Whether to apply an encoding before doing differential encoding. (e.g. gray coding)
+      bool apply_pre_diff_code() { return d_apply_pre_diff_code;}
+      //! Whether to apply an encoding before doing differential encoding. (e.g. gray coding)
+      void set_pre_diff_code(bool a) { d_apply_pre_diff_code = a;}
+      //! Returns the encoding to apply before differential encoding.
+      std::vector<unsigned int> pre_diff_code() { return d_pre_diff_code;}
+      //! Returns the order of rotational symmetry.
+      unsigned int rotational_symmetry() { return d_rotational_symmetry;}
+      //! Returns the number of complex numbers in a single symbol.
+      unsigned int dimensionality() {return d_dimensionality;}
+
+      unsigned int bits_per_symbol()
+      {
+	return floor(log(double(d_constellation.size()))/d_dimensionality/log(2.0));
+      }
+  
+      unsigned int arity()
+      {
+	return d_arity;
+      }
+
+      constellation_sptr base()
+      {
+	return shared_from_this();
+      }  
+
+    protected:
+      std::vector<gr_complex> d_constellation;
+      std::vector<unsigned int> d_pre_diff_code; 
+      bool d_apply_pre_diff_code;
+      unsigned int d_rotational_symmetry;
+      unsigned int d_dimensionality;
+      unsigned int d_arity;
+
+      float get_distance(unsigned int index, const gr_complex *sample);
+      unsigned int get_closest_point(const gr_complex *sample);
+      void calc_arity();
+    };
+
+    /************************************************************/
+    /* constellation_calcdist                                   */
+    /*                                                          */
+    /************************************************************/
+
+    /*! \brief Calculate Euclidian distance for any constellation
+     *  \ingroup digital
+     *
+     * Constellation which calculates the distance to each point in the
+     * constellation for decision making. Inefficient for large
+     * constellations.
+     */
+    class DIGITAL_API constellation_calcdist
+      : public constellation
+    {
+    public:
+      typedef boost::shared_ptr<constellation_calcdist> sptr;
+
+      // public constructor
+      static sptr make(std::vector<gr_complex> constell,
+		       std::vector<unsigned int> pre_diff_code,
+		       unsigned int rotational_symmetry,
+		       unsigned int dimensionality);
+
+      unsigned int decision_maker(const gr_complex *sample);
+      // void calc_metric(gr_complex *sample, float *metric, trellis_metric_type_t type);
+      // void calc_euclidean_metric(gr_complex *sample, float *metric);
+      // void calc_hard_symbol_metric(gr_complex *sample, float *metric);
+
+    private:
+      constellation_calcdist(std::vector<gr_complex> constell,
+			     std::vector<unsigned int> pre_diff_code,
+			     unsigned int rotational_symmetry,
+			     unsigned int dimensionality);
+    };
+
+
+    /************************************************************/
+    /*! constellation_sector                                    */
+    /************************************************************/
+
+    /*!
+     * \brief Sectorized digital constellation
+     * \ingroup digital
+     *
+     * Constellation space is divided into sectors. Each sector is
+     * associated with the nearest constellation point.
+     *
+     */
+    class DIGITAL_API constellation_sector : public constellation
+    {
+    public:
+
+      constellation_sector(std::vector<gr_complex> constell,
+			   std::vector<unsigned int> pre_diff_code,
+			   unsigned int rotational_symmetry,
+			   unsigned int dimensionality,
+			   unsigned int n_sectors);
+
+      unsigned int decision_maker(const gr_complex *sample);
+
+    protected:
+      virtual unsigned int get_sector(const gr_complex *sample) = 0;
+      virtual unsigned int calc_sector_value(unsigned int sector) = 0;
+      void find_sector_values();
+
+      unsigned int n_sectors;
+
+    private:
+      std::vector<unsigned int> sector_values;
+    };
+
+    /************************************************************/
+    /* constellation_rect                                       */
+    /************************************************************/
+
+    /*!
+     * \brief Rectangular digital constellation
+     * \ingroup digital
+     *
+     * Only implemented for 1-(complex)dimensional constellation.
+     *
+     * Constellation space is divided into rectangular sectors. Each
+     * sector is associated with the nearest constellation point.
+     *
+     * Works well for square QAM.
+     *
+     * Works for any generic constellation provided sectors are not
+     * too large.
+     */
+
+
+    class DIGITAL_API constellation_rect
+      : public constellation_sector
+    {
+    public:
+      typedef boost::shared_ptr<constellation_rect> sptr;
+
+      // public constructor
+      static constellation_rect::sptr make(std::vector<gr_complex> constell,
+					   std::vector<unsigned int> pre_diff_code,
+					   unsigned int rotational_symmetry,
+					   unsigned int real_sectors,
+					   unsigned int imag_sectors,
+					   float width_real_sectors,
+					   float width_imag_sectors);
+
+    protected:
+      unsigned int get_sector(const gr_complex *sample);
+  
+      unsigned int calc_sector_value(unsigned int sector);
+
+    private:
+      unsigned int n_real_sectors;
+      unsigned int n_imag_sectors;
+      float d_width_real_sectors;
+      float d_width_imag_sectors;
+
+      constellation_rect(std::vector<gr_complex> constell,
+			 std::vector<unsigned int> pre_diff_code,
+			 unsigned int rotational_symmetry,
+			 unsigned int real_sectors,
+			 unsigned int imag_sectors,
+			 float width_real_sectors,
+			 float width_imag_sectors);
+    };
+
+
+    /************************************************************/
+    /* constellation_psk                                        */
+    /************************************************************/
+
+    /*! 
+     * \brief constellation_psk
+     * \ingroup digital
+     *
+     * Constellation space is divided into pie slices sectors.
+     *
+     * Each slice is associated with the nearest constellation point. 
+     *
+     * Works well for PSK but nothing else.  
+     *
+     * Assumes that there is a constellation point at 1.x 
+     */
+    class DIGITAL_API constellation_psk : public constellation_sector
+    {
+    public:
+      typedef boost::shared_ptr<constellation_psk> sptr;
+
+      // public constructor
+      static sptr make(std::vector<gr_complex> constell,
+		       std::vector<unsigned int> pre_diff_code,
+		       unsigned int n_sectors);
+
+      ~constellation_psk();
+
+    protected:
+      unsigned int get_sector(const gr_complex *sample);
+  
+      unsigned int calc_sector_value(unsigned int sector);
+
+    private:
+      constellation_psk(std::vector<gr_complex> constell,
+			std::vector<unsigned int> pre_diff_code,
+			unsigned int n_sectors);
+    };
+
+
+    /************************************************************/
+    /* constellation_bpsk                                       */
+    /*                                                          */
+    /* Only works for BPSK.                                     */
+    /*                                                          */
+    /************************************************************/
+
+    /*! 
+     * \brief Digital constellation for BPSK 
+     * \ingroup digital
+     */
+    class DIGITAL_API constellation_bpsk : public constellation
+    {
+    public:
+      typedef boost::shared_ptr<constellation_bpsk> sptr;
+
+      // public constructor
+      static sptr make();
+
+      ~constellation_bpsk();
+
+      unsigned int decision_maker(const gr_complex *sample);
+
+    private:
+      constellation_bpsk();
+    };
+
+
+    /************************************************************/
+    /* constellation_qpsk                                       */
+    /*                                                          */
+    /* Only works for QPSK.                                     */
+    /*                                                          */
+    /************************************************************/
+
+    /*! 
+     * \brief Digital constellation for QPSK
+     * \ingroup digital
+     */
+    class DIGITAL_API constellation_qpsk : public constellation
+    {
+    public:
+      typedef boost::shared_ptr<constellation_qpsk> sptr;
+
+      // public constructor
+      static sptr make();
+
+      ~constellation_qpsk();
+
+      unsigned int decision_maker(const gr_complex *sample);
+
+    private:
+      constellation_qpsk();
+    };
+
+
+    /************************************************************/
+    /* constellation_dqpsk                                      */
+    /*                                                          */
+    /* Works with differential encoding; slower decisions.      */
+    /*                                                          */
+    /************************************************************/
+
+    /*!
+     * \brief Digital constellation for DQPSK
+     * \ingroup digital
+     */
+    class DIGITAL_API constellation_dqpsk : public constellation
+    {
+    public:
+      typedef boost::shared_ptr<constellation_dqpsk> sptr;
+
+      // public constructor
+      static sptr make();
+
+      ~constellation_dqpsk();
+
+      unsigned int decision_maker(const gr_complex *sample);
+
+    private:
+      constellation_dqpsk();
+    };
+
+
+    /************************************************************/
+    /* constellation_8psk                                       */
+    /*                                                          */
+    /* Only works for 8PSK.                                     */
+    /*                                                          */
+    /************************************************************/
+
+    /*! 
+     * \brief Digital constellation for 8PSK
+     * \ingroup digital
+     */
+    class DIGITAL_API constellation_8psk : public constellation
+    {
+    public:
+      typedef boost::shared_ptr<constellation_8psk> sptr;
+
+      // public constructor
+      static sptr make();
+
+      ~constellation_8psk();
+
+      unsigned int decision_maker(const gr_complex *sample);
+
+    private:
+      constellation_8psk();
+    };
+
+  } /* namespace digital */
+} /* namespace gr */
+
+#endif /* INCLUDED_DIGITAL_CONSTELLATION_H */
diff --git a/gr-digital/include/digital/constellation_decoder_cb.h b/gr-digital/include/digital/constellation_decoder_cb.h
new file mode 100644
index 0000000000..2a98cae643
--- /dev/null
+++ b/gr-digital/include/digital/constellation_decoder_cb.h
@@ -0,0 +1,55 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2011,2012 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio 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.
+ * 
+ * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_DIGITAL_CONSTELLATION_DECODER_CB_H
+#define INCLUDED_DIGITAL_CONSTELLATION_DECODER_CB_H
+
+#include <digital/api.h>
+#include <digital/constellation.h>
+#include <gr_block.h>
+
+namespace gr {
+  namespace digital {
+
+    /*!
+     * \brief Constellation Decoder
+     * \ingroup coding_blk
+     * \ingroup digital
+     *
+     */
+    class DIGITAL_API constellation_decoder_cb
+      : virtual public gr_block
+    {
+    public:
+      // gr::digital::constellation_decoder_cb::sptr
+      typedef boost::shared_ptr<constellation_decoder_cb> sptr;
+
+      /*!
+       * \brief Make constellation decoder block.
+       */
+      static sptr make(constellation_sptr constellation);
+    };
+
+  } /* namespace digital */
+} /* namespace gr */
+
+#endif /* INCLUDED_DIGITAL_CONSTELLATION_DECODER_CB_H */
diff --git a/gr-digital/include/digital/constellation_receiver_cb.h b/gr-digital/include/digital/constellation_receiver_cb.h
new file mode 100644
index 0000000000..b1c415ea09
--- /dev/null
+++ b/gr-digital/include/digital/constellation_receiver_cb.h
@@ -0,0 +1,93 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2011,2012 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio 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.
+ *
+ * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H
+#define	INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H
+
+#include <digital/api.h>
+#include <digital/constellation.h>
+#include <gr_block.h>
+
+namespace gr {
+  namespace digital {
+
+    /*!
+     * \brief This block takes care of receiving generic modulated signals
+     * through phase, frequency, and symbol synchronization.
+     * \ingroup sync_blk
+     * \ingroup demod_blk
+     * \ingroup digital
+     *
+     * This block takes care of receiving generic modulated signals
+     * through phase, frequency, and symbol synchronization. It
+     * performs carrier frequency and phase locking as well as symbol
+     * timing recovery.
+     *
+     * The phase and frequency synchronization are based on a Costas
+     * loop that finds the error of the incoming signal point compared
+     * to its nearest constellation point. The frequency and phase of
+     * the NCO are updated according to this error.
+     *
+     * The symbol synchronization is done using a modified Mueller and
+     * Muller circuit from the paper:
+     * 
+     * "G. R. Danesfahani, T.G. Jeans, "Optimisation of modified
+     * Mueller and Muller algorithm," Electronics Letters, Vol. 31,
+     * no. 13, 22 June 1995, pp. 1032 - 1033."
+     *
+     * This circuit interpolates the downconverted sample (using the
+     * NCO developed by the Costas loop) every mu samples, then it
+     * finds the sampling error based on this and the past symbols and
+     * the decision made on the samples. Like the phase error
+     * detector, there are optimized decision algorithms for BPSK and
+     * QPKS, but 8PSK uses another brute force computation against all
+     * possible symbols. The modifications to the M&M used here reduce
+     * self-noise.
+     */
+    class DIGITAL_API constellation_receiver_cb
+      : virtual public gr_block
+    {
+    public:
+      // gr::digital::constellation_receiver_cb::sptr
+      typedef boost::shared_ptr<constellation_receiver_cb> sptr;
+
+      /*!
+       * \brief Constructor to synchronize incoming M-PSK symbols
+       *
+       * \param constellation constellation of points for generic modulation
+       * \param loop_bw	Loop  bandwidth of the Costas Loop (~ 2pi/100)
+       * \param fmin          minimum normalized frequency value the loop can achieve
+       * \param fmax          maximum normalized frequency value the loop can achieve
+       *
+       * The constructor chooses which phase detector and decision
+       * maker to use in the work loop based on the value of M.
+       */
+      static sptr make(constellation_sptr constellation, 
+		       float loop_bw, float fmin, float fmax);
+
+      virtual void phase_error_tracking(float phase_error) = 0;
+    };
+
+  } /* namespace digital */
+} /* namespace gr */
+
+#endif /* INCLUDED_DIGITAL_CONSTELLATION_RECEIVER_CB_H */
author	Tom Rondeau <trondeau@vt.edu>	2012-08-11 11:04:03 -0400
committer	Tom Rondeau <trondeau@vt.edu>	2012-08-11 11:04:03 -0400
commit	a6e56683cf74054fad6774138bea9f844c76be09 (patch)
tree	1749031397ac4ebdc117b05a753c82976e8aca62 /gr-digital/include/digital
parent	af0a5780201c71c8f2d682cdab2274942e5771d5 (diff)