From e832b09166547e380972f48b2317d96a25d3d0e5 Mon Sep 17 00:00:00 2001 From: Tom Rondeau Date: Sat, 5 May 2012 14:41:03 -0400 Subject: filter: added Parks-McClellen algorithm. Renamed gr_remez to pm_remez here. Added QA code and fixed coding style. --- gr-filter/include/filter/CMakeLists.txt | 1 + gr-filter/include/filter/pm_remez.h | 72 +++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+) create mode 100644 gr-filter/include/filter/pm_remez.h (limited to 'gr-filter/include') diff --git a/gr-filter/include/filter/CMakeLists.txt b/gr-filter/include/filter/CMakeLists.txt index 108509e9a..cdb07b2f9 100644 --- a/gr-filter/include/filter/CMakeLists.txt +++ b/gr-filter/include/filter/CMakeLists.txt @@ -76,6 +76,7 @@ add_custom_target(filter_generated_includes DEPENDS install(FILES api.h firdes.h + pm_remez.h fir_filter.h fft_filter.h ${generated_includes} diff --git a/gr-filter/include/filter/pm_remez.h b/gr-filter/include/filter/pm_remez.h new file mode 100644 index 000000000..a57e9e276 --- /dev/null +++ b/gr-filter/include/filter/pm_remez.h @@ -0,0 +1,72 @@ +/* -*- c++ -*- */ +/* + * Copyright 2004,2012 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_FILTER_PM_REMEZ_H +#define INCLUDED_FILTER_PM_REMEZ_H + +#include +#include +#include +#include + +namespace gr { + namespace filter { + /*! + * \brief Parks-McClellan FIR filter design using Remez algorithm. + * + * \ingroup filter_design + * + * Calculates the optimal (in the Chebyshev/minimax sense) FIR + * filter inpulse reponse given a set of band edges, the desired + * reponse on those bands, and the weight given to the error in + * those bands. + * + * \param order filter order (number of taps in the returned filter - 1) + * \param bands frequency at the band edges [ b1 e1 b2 e2 b3 e3 ...] + * \param ampl desired amplitude at the band edges [ a(b1) a(e1) a(b2) a(e2) ...] + * \param error_weight weighting applied to each band (usually 1) + * \param filter_type one of "bandpass", "hilbert" or "differentiator" + * \param grid_density determines how accurately the filter will be constructed. \ + * The minimum value is 16; higher values are slower to compute. + * + * Frequency is in the range [0, 1], with 1 being the Nyquist + * frequency (Fs/2) + * + * \returns vector of computed taps + * + * \throws std::runtime_error if args are invalid or calculation + * fails to converge. + */ + + FILTER_API std::vector + pm_remez(int order, + const std::vector &bands, + const std::vector &l, + const std::vector &error_weight, + const std::string filter_type = "bandpass", + int grid_density = 16 + ) throw (std::runtime_error); + + } /* namespace filter */ +} /* namespace gr */ + +#endif /* INCLUDED_FILTER_PM_REMEZ_H */ -- cgit