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			109 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			109 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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| //                                                                               //
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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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| 
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| #include <QtGlobal>
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| #include <stdio.h>
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| #define _USE_MATH_DEFINES
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| #include <math.h>
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| #include "dsp/nco.h"
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| 
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| #undef M_PI
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| #define M_PI		3.14159265358979323846
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| 
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| Real NCO::m_table[NCO::TableSize];
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| bool NCO::m_tableInitialized = false;
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| 
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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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| 
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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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| 
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| 	m_tableInitialized = true;
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| }
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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