diff options
| author | Tom Rondeau <trondeau@vt.edu> | 2012-08-14 19:23:41 -0400 |
|---|---|---|
| committer | Tom Rondeau <trondeau@vt.edu> | 2012-08-14 19:23:41 -0400 |
| commit | ab479e3d5b5d77eb4133dd06ea3ffc51551fccd6 (patch) | |
| tree | aadbda22cf4c7dc3ff808948dc6dea8d9da4b983 /gr-digital/include/digital | |
| parent | 48a95b3469febf4929c74f41beac6b33ab77566e (diff) | |
digital: converted mpsk_receiver to new style.
Diffstat (limited to 'gr-digital/include/digital')
| -rw-r--r-- | gr-digital/include/digital/CMakeLists.txt | 2 | ||||
| -rw-r--r-- | gr-digital/include/digital/mpsk_receiver_cc.h | 147 |
2 files changed, 148 insertions, 1 deletions
diff --git a/gr-digital/include/digital/CMakeLists.txt b/gr-digital/include/digital/CMakeLists.txt index 2445a6fe37..27e151e0a5 100644 --- a/gr-digital/include/digital/CMakeLists.txt +++ b/gr-digital/include/digital/CMakeLists.txt @@ -104,7 +104,7 @@ install(FILES # kurtotic_equalizer_cc.h map_bb.h # metric_type.h -# mpsk_receiver_cc.h + mpsk_receiver_cc.h mpsk_snr_est_cc.h # ofdm_cyclic_prefixer.h # ofdm_frame_acquisition.h diff --git a/gr-digital/include/digital/mpsk_receiver_cc.h b/gr-digital/include/digital/mpsk_receiver_cc.h new file mode 100644 index 0000000000..14094e25b7 --- /dev/null +++ b/gr-digital/include/digital/mpsk_receiver_cc.h @@ -0,0 +1,147 @@ +/* -*- c++ -*- */ +/* + * Copyright 2004,2007,2011,2012 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_MPSK_RECEIVER_CC_H +#define INCLUDED_DIGITAL_MPSK_RECEIVER_CC_H + +#include <digital/api.h> +#include <gr_block.h> + +namespace gr { + namespace digital { + + /*! + * \brief This block takes care of receiving M-PSK modulated + * signals through phase, frequency, and symbol synchronization. + * \ingroup sync_blk + * \ingroup demod_blk + * \ingroup digital + * + * 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_API mpsk_receiver_cc : virtual public gr_block + { + public: + // gr::digital::mpsk_receiver_cc::sptr + typedef boost::shared_ptr<mpsk_receiver_cc> sptr; + + /*! + * \brief Buil M-PSK receiver block. + * + * \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. + */ + static sptr make(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); + + //! Returns the modulation order (M) currently set + virtual float modulation_order() const = 0; + + //! Returns current value of theta + virtual float theta() const = 0; + + //! Returns current value of mu + virtual float mu() const = 0; + + //! Returns current value of omega + virtual float omega() const = 0; + + //! Returns mu gain factor + virtual float gain_mu() const = 0; + + //! Returns omega gain factor + virtual float gain_omega() const = 0; + + //! Returns the relative omega limit + virtual float gain_omega_rel() const = 0; + + //! Sets the modulation order (M) currently + virtual void set_modulation_order(unsigned int M) = 0; + + //! Sets value of theta + virtual void set_theta(float theta) = 0; + + //! Sets value of mu + virtual void set_mu(float mu) = 0; + + //! Sets value of omega and its min and max values + virtual void set_omega(float omega) = 0; + + //! Sets value for mu gain factor + virtual void set_gain_mu(float gain_mu) = 0; + + //! Sets value for omega gain factor + virtual void set_gain_omega(float gain_omega) = 0; + + //! Sets the relative omega limit and resets omega min/max values + virtual void set_gain_omega_rel(float omega_rel) = 0; + }; + + } /* namespace digital */ +} /* namespace gr */ + +#endif /* INCLUDED_DIGITAL_MPSK_RECEIVER_CC_H */ |