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Diffstat (limited to 'gr-digital/lib/digital_mpsk_receiver_cc.h')
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diff --git a/gr-digital/lib/digital_mpsk_receiver_cc.h b/gr-digital/lib/digital_mpsk_receiver_cc.h deleted file mode 100644 index f8aa4e341..000000000 --- a/gr-digital/lib/digital_mpsk_receiver_cc.h +++ /dev/null @@ -1,301 +0,0 @@ -/* -*- c++ -*- */ -/* - * Copyright 2004,2007,2011 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_MPSK_RECEIVER_CC_H -#define INCLUDED_DIGITAL_MPSK_RECEIVER_CC_H - -#include <gruel/attributes.h> -#include <gri_control_loop.h> -#include <gr_block.h> -#include <gr_complex.h> -#include <fstream> - -class gri_mmse_fir_interpolator_cc; - -class digital_mpsk_receiver_cc; -typedef boost::shared_ptr<digital_mpsk_receiver_cc> digital_mpsk_receiver_cc_sptr; - -// public constructor -digital_mpsk_receiver_cc_sptr -digital_make_mpsk_receiver_cc (unsigned int M, float theta, - float loop_bw, - float fmin, float fmax, - float mu, float gain_mu, - float omega, float gain_omega, float omega_rel); - -/*! - * \brief This block takes care of receiving M-PSK modulated signals - * through phase, frequency, and symbol synchronization. - * \ingroup sync_blk - * \ingroup demod_blk - * - * This block takes care of receiving M-PSK modulated signals through - * phase, frequency, and symbol synchronization. It performs carrier - * frequency and phase locking as well as symbol timing recovery. It - * works with (D)BPSK, (D)QPSK, and (D)8PSK as tested currently. It - * should also work for OQPSK and PI/4 DQPSK. - * - * 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. There are optimized phase error - * detectors for BPSK and QPSK, but 8PSK is done using a brute-force - * computation of the constellation points to find the minimum. - * - * 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_mpsk_receiver_cc : public gr_block, public gri_control_loop -{ - public: - ~digital_mpsk_receiver_cc (); - void forecast(int noutput_items, gr_vector_int &ninput_items_required); - int general_work (int noutput_items, - gr_vector_int &ninput_items, - gr_vector_const_void_star &input_items, - gr_vector_void_star &output_items); - - - // Member functions related to the symbol tracking portion of the receiver - //! (M&M) Returns current value of mu - float mu() const { return d_mu;} - - //! (M&M) Returns current value of omega - float omega() const { return d_omega;} - - //! (M&M) Returns mu gain factor - float gain_mu() const { return d_gain_mu;} - - //! (M&M) Returns omega gain factor - float gain_omega() const { return d_gain_omega;} - - //! (M&M) Sets value of mu - void set_mu (float mu) { d_mu = mu; } - - //! (M&M) Sets value of omega and its min and max values - void set_omega (float omega) { - d_omega = omega; - d_min_omega = omega*(1.0 - d_omega_rel); - d_max_omega = omega*(1.0 + d_omega_rel); - d_omega_mid = 0.5*(d_min_omega+d_max_omega); - } - - //! (M&M) Sets value for mu gain factor - void set_gain_mu (float gain_mu) { d_gain_mu = gain_mu; } - - //! (M&M) Sets value for omega gain factor - void set_gain_omega (float gain_omega) { d_gain_omega = gain_omega; } - -protected: - - /*! - * \brief Constructor to synchronize incoming M-PSK symbols - * - * \param M modulation order of the M-PSK modulation - * \param theta any constant phase rotation from the real axis of the constellation - * \param loop_bw Loop bandwidth to set gains of phase/freq tracking loop - * \param fmin minimum normalized frequency value the loop can achieve - * \param fmax maximum normalized frequency value the loop can achieve - * \param mu initial parameter for the interpolator [0,1] - * \param gain_mu gain parameter of the M&M error signal to adjust mu (~0.05) - * \param omega initial value for the number of symbols between samples (~number of samples/symbol) - * \param gain_omega gain parameter to adjust omega based on the error (~omega^2/4) - * \param omega_rel sets the maximum (omega*(1+omega_rel)) and minimum (omega*(1+omega_rel)) omega (~0.005) - * - * The constructor also chooses which phase detector and decision maker to use in the work loop based on the - * value of M. - */ - digital_mpsk_receiver_cc (unsigned int M, float theta, - float loop_bw, - float fmin, float fmax, - float mu, float gain_mu, - float omega, float gain_omega, float omega_rel); - - void make_constellation(); - void mm_sampler(const gr_complex symbol); - void mm_error_tracking(gr_complex sample); - void phase_error_tracking(gr_complex sample); - - - /*! - * \brief Phase error detector for MPSK modulations. - * - * \param sample the I&Q sample from which to determine the phase error - * - * This function determines the phase error for any MPSK signal by - * creating a set of PSK constellation points and doing a - * brute-force search to see which point minimizes the Euclidean - * distance. This point is then used to derotate the sample to the - * real-axis and a atan (using the fast approximation function) to - * determine the phase difference between the incoming sample and - * the real constellation point - * - * This should be cleaned up and made more efficient. - * - * \returns the approximated phase error. - */ - float phase_error_detector_generic(gr_complex sample) const; // generic for M but more costly - - /*! - * \brief Phase error detector for BPSK modulation. - * - * \param sample the I&Q sample from which to determine the phase error - * - * This function determines the phase error using a simple BPSK - * phase error detector by multiplying the real and imaginary (the - * error signal) components together. As the imaginary part goes to - * 0, so does this error. - * - * \returns the approximated phase error. - */ - float phase_error_detector_bpsk(gr_complex sample) const; // optimized for BPSK - - /*! - * \brief Phase error detector for QPSK modulation. - * - * \param sample the I&Q sample from which to determine the phase error - * - * This function determines the phase error using the limiter - * approach in a standard 4th order Costas loop - * - * \returns the approximated phase error. - */ - float phase_error_detector_qpsk(gr_complex sample) const; - - - - /*! - * \brief Decision maker for a generic MPSK constellation. - * - * \param sample the baseband I&Q sample from which to make the decision - * - * This decision maker is a generic implementation that does a - * brute-force search for the constellation point that minimizes the - * error between it and the incoming signal. - * - * \returns the index to d_constellation that minimizes the error/ - */ - unsigned int decision_generic(gr_complex sample) const; - - - /*! - * \brief Decision maker for BPSK constellation. - * - * \param sample the baseband I&Q sample from which to make the decision - * - * This decision maker is a simple slicer function that makes a - * decision on the symbol based on its placement on the real axis of - * greater than 0 or less than 0; the quadrature component is always - * 0. - * - * \returns the index to d_constellation that minimizes the error/ - */ - unsigned int decision_bpsk(gr_complex sample) const; - - - /*! - * \brief Decision maker for QPSK constellation. - * - * \param sample the baseband I&Q sample from which to make the decision - * - * This decision maker is a simple slicer function that makes a - * decision on the symbol based on its placement versus both axes - * and returns which quadrant the symbol is in. - * - * \returns the index to d_constellation that minimizes the error/ - */ - unsigned int decision_qpsk(gr_complex sample) const; - -private: - unsigned int d_M; - float d_theta; - - /*! - * \brief Decision maker function pointer - * - * \param sample the baseband I&Q sample from which to make the decision - * - * This is a function pointer that is set in the constructor to - * point to the proper decision function for the specified - * constellation order. - * - * \return index into d_constellation point that is the closest to the recieved sample - */ - unsigned int (digital_mpsk_receiver_cc::*d_decision)(gr_complex sample) const; // pointer to decision function - - - std::vector<gr_complex> d_constellation; - unsigned int d_current_const_point; - - // Members related to symbol timing - float d_mu, d_gain_mu; - float d_omega, d_gain_omega, d_omega_rel, d_max_omega, d_min_omega, d_omega_mid; - gr_complex d_p_2T, d_p_1T, d_p_0T; - gr_complex d_c_2T, d_c_1T, d_c_0T; - - /*! - * \brief Phase error detector function pointer - * - * \param sample the I&Q sample from which to determine the phase error - * - * This is a function pointer that is set in the constructor to - * point to the proper phase error detector function for the - * specified constellation order. - */ - float (digital_mpsk_receiver_cc::*d_phase_error_detector)(gr_complex sample) const; - - - //! get interpolated value - gri_mmse_fir_interpolator_cc *d_interp; - - //! delay line length. - static const unsigned int DLLEN = 8; - - //! delay line plus some length for overflow protection - __GR_ATTR_ALIGNED(8) gr_complex d_dl[2*DLLEN]; - - //! index to delay line - unsigned int d_dl_idx; - - friend digital_mpsk_receiver_cc_sptr - digital_make_mpsk_receiver_cc (unsigned int M, float theta, - float loop_bw, - float fmin, float fmax, - float mu, float gain_mu, - float omega, float gain_omega, float omega_rel); -}; - -#endif |