diff options
Diffstat (limited to 'gr-analog/lib/probe_avg_mag_sqrd_c_impl.cc')
-rw-r--r-- | gr-analog/lib/probe_avg_mag_sqrd_c_impl.cc | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/gr-analog/lib/probe_avg_mag_sqrd_c_impl.cc b/gr-analog/lib/probe_avg_mag_sqrd_c_impl.cc new file mode 100644 index 000000000..291809bb2 --- /dev/null +++ b/gr-analog/lib/probe_avg_mag_sqrd_c_impl.cc @@ -0,0 +1,91 @@ +/* -*- 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 "probe_avg_mag_sqrd_c_impl.h" +#include <gr_io_signature.h> +#include <cmath> + +namespace gr { + namespace analog { + + probe_avg_mag_sqrd_c::sptr + probe_avg_mag_sqrd_c::make(double threshold_db, double alpha) + { + return gnuradio::get_initial_sptr + (new probe_avg_mag_sqrd_c_impl(threshold_db, alpha)); + } + + probe_avg_mag_sqrd_c_impl::probe_avg_mag_sqrd_c_impl(double threshold_db, double alpha) + : gr_sync_block("probe_avg_mag_sqrd_c", + gr_make_io_signature(1, 1, sizeof(gr_complex)), + gr_make_io_signature(0, 0, 0)), + d_unmuted(false), d_level(0), d_iir(alpha) + { + set_threshold(threshold_db); + } + + probe_avg_mag_sqrd_c_impl::~probe_avg_mag_sqrd_c_impl() + { + } + + int + probe_avg_mag_sqrd_c_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]; + + for(int i = 0; i < noutput_items; i++) { + double mag_sqrd = in[i].real()*in[i].real() + in[i].imag()*in[i].imag(); + d_iir.filter(mag_sqrd); // computed for side effect: prev_output() + } + + d_unmuted = d_iir.prev_output() >= d_threshold; + d_level = d_iir.prev_output(); + return noutput_items; + } + + double + probe_avg_mag_sqrd_c_impl::threshold() const + { + return 10 * std::log10(d_threshold); + } + + void + probe_avg_mag_sqrd_c_impl::set_threshold(double decibels) + { + // convert to absolute threshold (mag squared) + d_threshold = std::pow(10.0, decibels/10); + } + + void + probe_avg_mag_sqrd_c_impl::set_alpha(double alpha) + { + d_iir.set_taps(alpha); + } + + } /* namespace analog */ +} /* namespace gr */ |