/* -*- 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_PROBE_MPSK_SNR_EST_C_H #define INCLUDED_DIGITAL_PROBE_MPSK_SNR_EST_C_H #include <gnuradio/digital/api.h> #include <gnuradio/digital/mpsk_snr_est.h> #include <gnuradio/sync_block.h> namespace gr { namespace digital { /*! * \brief A probe for computing SNR of a PSK signal. * \ingroup measurement_tools_blk * * \details * This is a probe block (a sink) that can be used to monitor and * retrieve estimations of the signal SNR. This probe is designed * for use with M-PSK signals especially. The type of estimator is * specified as the \p type parameter in the constructor. The * estimators tend to trade off performance for accuracy, although * experimentation should be done to figure out the right approach * for a given implementation. Further, the current set of * estimators are designed and proven theoretically under AWGN * conditions; some amount of error should be assumed and/or * estimated for real channel conditions. * * The block has three output message ports that will emit a * message every msg_samples number of samples. These message * ports are: * \li snr: the current SNR estimate (in dB) * \li signal: the current signal power estimate (in dBx) * \li noise: the current noise power estimate (in dBx) * * Some calibration is required to convert dBx of the signal and * noise power estimates to real measurements, such as dBm. */ class DIGITAL_API probe_mpsk_snr_est_c : virtual public sync_block { public: // gr::digital::probe_mpsk_snr_est_c::sptr typedef boost::shared_ptr<probe_mpsk_snr_est_c> sptr; /*! Make an MPSK SNR probe. * * Parameters: * * \param type: the type of estimator to use see * gr::digital::snr_est_type_t for details about the types. * \param msg_nsamples: [not implemented yet] after this many * samples, a message containing the SNR (key='snr') will be sent * \param alpha: the update rate of internal running average * calculations. */ static sptr make(snr_est_type_t type, int msg_nsamples=10000, double alpha=0.001); //! Return the estimated signal-to-noise ratio in decibels virtual double snr() = 0; //! Return the estimated signal power in decibels virtual double signal() = 0; //! Return the estimated noise power in decibels virtual double noise() = 0; //! Return the type of estimator in use virtual snr_est_type_t type() const = 0; //! Return how many samples between SNR messages virtual int msg_nsample() const = 0; //! Get the running-average coefficient virtual double alpha() const = 0; //! Set type of estimator to use virtual void set_type(snr_est_type_t t) = 0; //! Set the number of samples between SNR messages virtual void set_msg_nsample(int n) = 0; //! Set the running-average coefficient virtual void set_alpha(double alpha) = 0; }; } /* namespace digital */ } /* namespace gr */ #endif /* INCLUDED_DIGITAL_PROBE_MPSK_SNR_EST_C_H */