diff options
Diffstat (limited to 'gr-analog/lib')
| -rw-r--r-- | gr-analog/lib/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | gr-analog/lib/simple_squelch_cc_impl.cc | 106 | ||||
| -rw-r--r-- | gr-analog/lib/simple_squelch_cc_impl.h | 59 |
3 files changed, 166 insertions, 0 deletions
diff --git a/gr-analog/lib/CMakeLists.txt b/gr-analog/lib/CMakeLists.txt index 6b64c019d..0aed18405 100644 --- a/gr-analog/lib/CMakeLists.txt +++ b/gr-analog/lib/CMakeLists.txt @@ -126,6 +126,7 @@ list(APPEND analog_sources probe_avg_mag_sqrd_c_impl.cc probe_avg_mag_sqrd_cf_impl.cc probe_avg_mag_sqrd_f_impl.cc + simple_squelch_cc_impl.cc ) list(APPEND analog_libs diff --git a/gr-analog/lib/simple_squelch_cc_impl.cc b/gr-analog/lib/simple_squelch_cc_impl.cc new file mode 100644 index 000000000..02ccc535d --- /dev/null +++ b/gr-analog/lib/simple_squelch_cc_impl.cc @@ -0,0 +1,106 @@ +/* -*- c++ -*- */ +/* + * Copyright 2005,2010,2012 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. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "simple_squelch_cc_impl.h" +#include <gr_io_signature.h> +#include <cmath> + +namespace gr { + namespace analog { + + simple_squelch_cc::sptr + simple_squelch_cc::make(double threshold_db, double alpha) + { + return gnuradio::get_initial_sptr + (new simple_squelch_cc_impl(threshold_db, alpha)); + } + + simple_squelch_cc_impl::simple_squelch_cc_impl(double threshold_db, double alpha) + : gr_sync_block("simple_squelch_cc", + gr_make_io_signature(1, 1, sizeof(gr_complex)), + gr_make_io_signature(1, 1, sizeof(gr_complex))), + d_unmuted(false), d_iir(alpha) + { + set_threshold(threshold_db); + } + + simple_squelch_cc_impl::~simple_squelch_cc_impl() + { + } + + void + simple_squelch_cc_impl::set_threshold(double decibels) + { + // convert to absolute threshold (mag squared) + d_threshold = std::pow(10.0, decibels/10); + } + + double + simple_squelch_cc_impl::threshold() const + { + return 10 * log10(d_threshold); + } + + void + simple_squelch_cc_impl::set_alpha(double alpha) + { + d_iir.set_taps(alpha); + } + + std::vector<float> + simple_squelch_cc_impl::squelch_range() const + { + std::vector<float> r(3); + r[0] = -50.0; // min FIXME + r[1] = +50.0; // max FIXME + r[2] = (r[1] - r[0]) / 100; // step size + + return r; + } + + int + simple_squelch_cc_impl::work(int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) + { + const gr_complex *in = (const gr_complex*)input_items[0]; + gr_complex *out = (gr_complex*)output_items[0]; + + for(int i = 0; i < noutput_items; i++) { + double mag_sqrd = in[i].real()*in[i].real() + in[i].imag()*in[i].imag(); + double f = d_iir.filter(mag_sqrd); + if(f >= d_threshold) + out[i] = in[i]; + else + out[i] = 0; + } + + d_unmuted = d_iir.prev_output() >= d_threshold; + return noutput_items; + } + + } /* namespace analog */ +} /* namespace gr */ diff --git a/gr-analog/lib/simple_squelch_cc_impl.h b/gr-analog/lib/simple_squelch_cc_impl.h new file mode 100644 index 000000000..ba11de91e --- /dev/null +++ b/gr-analog/lib/simple_squelch_cc_impl.h @@ -0,0 +1,59 @@ +/* -*- c++ -*- */ +/* + * Copyright 2005,2012 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_ANALOG_SIMPLE_SQUELCH_CC_IMPL_H +#define INCLUDED_ANALOG_SIMPLE_SQUELCH_CC_IMPL_H + +#include <analog/simple_squelch_cc.h> +#include <filter/single_pole_iir.h> + +namespace gr { + namespace analog { + + class simple_squelch_cc_impl : public simple_squelch_cc + { + private: + double d_threshold; + bool d_unmuted; + filter::single_pole_iir<double,double,double> d_iir; + + public: + simple_squelch_cc_impl(double threshold_db, double alpha); + ~simple_squelch_cc_impl(); + + bool unmuted() const { return d_unmuted; } + + void set_alpha(double alpha); + void set_threshold(double decibels); + + double threshold() const; + std::vector<float> squelch_range() const; + + int work(int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items); + }; + + } /* namespace analog */ +} /* namespace gr */ + +#endif /* INCLUDED_ANALOG_SIMPLE_SQUELCH_CC_IMPL_H */ |