2015-12-07 20:00:30 -05:00
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///////////////////////////////////////////////////////////////////////////////////
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// Copyright (C) 2015 F4EXB //
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// written by Edouard Griffiths //
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// //
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// This program is free software; you can redistribute it and/or modify //
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// it under the terms of the GNU General Public License as published by //
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// the Free Software Foundation as version 3 of the License, or //
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// //
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// This program is distributed in the hope that it will be useful, //
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// but WITHOUT ANY WARRANTY; without even the implied warranty of //
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
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// GNU General Public License V3 for more details. //
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// //
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// You should have received a copy of the GNU General Public License //
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// along with this program. If not, see <http://www.gnu.org/licenses/>. //
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///////////////////////////////////////////////////////////////////////////////////
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#ifndef INCLUDE_DSP_FILTERRC_H_
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#define INCLUDE_DSP_FILTERRC_H_
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#include "dsp/dsptypes.h"
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2018-03-20 08:49:21 -04:00
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#include "export.h"
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2015-12-07 20:00:30 -05:00
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/** First order low-pass IIR filter for real-valued signals. */
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2018-03-03 14:23:38 -05:00
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class SDRBASE_API LowPassFilterRC
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2015-12-07 20:00:30 -05:00
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{
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public:
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/**
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* Construct 1st order low-pass IIR filter.
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*
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* timeconst :: RC time constant in seconds (1 / (2 * PI * cutoff_freq)
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*/
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LowPassFilterRC(Real timeconst);
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/**
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* Reconfigure filter with new time constant
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*/
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void configure(Real timeout);
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/** Process samples. */
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void process(const Real& sample_in, Real& sample_out);
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private:
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Real m_timeconst;
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Real m_y1;
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Real m_a1;
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Real m_b0;
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};
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#endif /* INCLUDE_DSP_FILTERRC_H_ */
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