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107 lines
3.0 KiB
C++
107 lines
3.0 KiB
C++
///////////////////////////////////////////////////////////////////////////////////
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// Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany //
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// written by Christian Daniel //
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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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// (at your option) any later version. //
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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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#include <QtGlobal>
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#include <cstdio>
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#include <cmath>
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#include "dsp/nco.h"
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Real NCO::m_table[NCO::TableSize];
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bool NCO::m_tableInitialized = false;
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void NCO::initTable()
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{
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if(m_tableInitialized)
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return;
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for(int i = 0; i < TableSize; i++)
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m_table[i] = cos((2.0 * M_PI * i) / TableSize);
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m_tableInitialized = true;
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}
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NCO::NCO()
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{
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initTable();
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m_phase = 0;
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m_phaseIncrement = 0;
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}
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void NCO::setFreq(Real freq, Real sampleRate)
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{
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m_phaseIncrement = (freq * TableSize) / sampleRate;
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qDebug("NCO freq: %f phase inc %d", freq, m_phaseIncrement);
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}
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float NCO::next()
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{
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nextPhase();
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return m_table[m_phase];
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}
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Complex NCO::nextIQ()
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{
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nextPhase();
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return Complex(m_table[m_phase], -m_table[(m_phase + TableSize / 4) % TableSize]);
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}
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Complex NCO::nextQI()
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{
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nextPhase();
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return Complex(-m_table[(m_phase + TableSize / 4) % TableSize], m_table[m_phase]);
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}
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void NCO::nextIQMul(Real& i, Real& q)
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{
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nextPhase();
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Real x = i;
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Real y = q;
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const Real& u = m_table[m_phase];
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const Real& v = -m_table[(m_phase + TableSize / 4) % TableSize];
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i = x*u - y*v;
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q = x*v + y*u;
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}
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float NCO::get()
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{
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return m_table[m_phase];
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}
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Complex NCO::getIQ()
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{
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return Complex(m_table[m_phase], -m_table[(m_phase + TableSize / 4) % TableSize]);
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}
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void NCO::getIQ(Complex& c)
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{
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c.real(m_table[m_phase]);
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c.imag(-m_table[(m_phase + TableSize / 4) % TableSize]);
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}
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Complex NCO::getQI()
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{
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return Complex(-m_table[(m_phase + TableSize / 4) % TableSize], m_table[m_phase]);
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}
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void NCO::getQI(Complex& c)
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{
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c.imag(m_table[m_phase]);
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c.real(-m_table[(m_phase + TableSize / 4) % TableSize]);
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}
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