///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2019 F4EXB //
// written by Edouard Griffiths //
// //
// This program 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 as version 3 of the License, or //
// (at your option) any later version. //
// //
// This program 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 V3 for more details. //
// //
// You should have received a copy of the GNU General Public License //
// along with this program. If not, see <http://www.gnu.org/licenses/>. //
///////////////////////////////////////////////////////////////////////////////////
#include <QDebug>
#include "devicesamplestatic.h"
int64_t DeviceSampleStatic::calculateSourceDeviceCenterFrequency(
uint64_t centerFrequency,
int64_t transverterDeltaFrequency,
int log2Decim,
fcPos_t fcPos,
uint32_t devSampleRate,
FrequencyShiftScheme frequencyShiftScheme,
bool transverterMode)
{
int64_t deviceCenterFrequency = centerFrequency;
deviceCenterFrequency -= transverterMode ? transverterDeltaFrequency : 0;
deviceCenterFrequency = deviceCenterFrequency < 0 ? 0 : deviceCenterFrequency;
int64_t f_img = deviceCenterFrequency;
deviceCenterFrequency -= calculateSourceFrequencyShift(log2Decim, fcPos, devSampleRate, frequencyShiftScheme);
f_img -= 2*calculateSourceFrequencyShift(log2Decim, fcPos, devSampleRate, frequencyShiftScheme);
qDebug() << "DeviceSampleStatic::calculateSourceDeviceCenterFrequency:"
<< " frequencyShiftScheme: " << frequencyShiftScheme
<< " desired center freq: " << centerFrequency << " Hz"
<< " device center freq: " << deviceCenterFrequency << " Hz"
<< " device sample rate: " << devSampleRate << "S/s"
<< " Actual sample rate: " << devSampleRate/(1<<log2Decim) << "S/s"
<< " center freq position code: " << fcPos
<< " image frequency: " << f_img << "Hz";
return deviceCenterFrequency;
}
int64_t DeviceSampleStatic::calculateSourceCenterFrequency(
uint64_t deviceCenterFrequency,
int64_t transverterDeltaFrequency,
int log2Decim,
fcPos_t fcPos,
uint32_t devSampleRate,
FrequencyShiftScheme frequencyShiftScheme,
bool transverterMode)
{
qint64 centerFrequency = deviceCenterFrequency;
centerFrequency += calculateSourceFrequencyShift(log2Decim, fcPos, devSampleRate, frequencyShiftScheme);
centerFrequency += transverterMode ? transverterDeltaFrequency : 0;
centerFrequency = centerFrequency < 0 ? 0 : centerFrequency;
qDebug() << "DeviceSampleStatic::calculateSourceCenterFrequency:"
<< " frequencyShiftScheme: " << frequencyShiftScheme
<< " desired center freq: " << centerFrequency << " Hz"
<< " device center freq: " << deviceCenterFrequency << " Hz"
<< " device sample rate: " << devSampleRate << "S/s"
<< " Actual sample rate: " << devSampleRate/(1<<log2Decim) << "S/s"
<< " center freq position code: " << fcPos;
return centerFrequency;
}
/**
* log2Decim = 0: no shift
*
* n = log2Decim <= 2: fc = +/- 1/2^(n-1)
* center
* | ^ |
* | inf | sup |
* ^ ^
*
* n = log2Decim > 2: fc = +/- 1/2^n
* center
* | ^ |
* | |inf| | |sup| |
* ^ ^
*/
int DeviceSampleStatic::calculateSourceFrequencyShift(
int log2Decim,
fcPos_t fcPos,
uint32_t devSampleRate,
FrequencyShiftScheme frequencyShiftScheme)
{
if (frequencyShiftScheme == FSHIFT_STD)
{
if (log2Decim == 0) { // no shift at all
return 0;
} else if (log2Decim < 3) {
if (fcPos == FC_POS_INFRA) { // shift in the square next to center frequency
return -(devSampleRate / (1<<(log2Decim+1)));
} else if (fcPos == FC_POS_SUPRA) {
return devSampleRate / (1<<(log2Decim+1));
} else {
return 0;
}
} else {
if (fcPos == FC_POS_INFRA) { // shift centered in the square next to center frequency
return -(devSampleRate / (1<<(log2Decim)));
} else if (fcPos == FC_POS_SUPRA) {
return devSampleRate / (1<<(log2Decim));
} else {
return 0;
}
}
}
else // frequencyShiftScheme == FSHIFT_TXSYNC
{
if (fcPos == FC_POS_CENTER) {
return 0;
}
int sign = fcPos == FC_POS_INFRA ? -1 : 1;
int halfSampleRate = devSampleRate / 2; // fractions are relative to sideband thus based on half the sample rate
if (log2Decim == 0) {
return 0;
} else if (log2Decim == 1) {
return sign * (halfSampleRate / 2); // inf or sup: 1/2
} else if (log2Decim == 2) {
return sign * ((halfSampleRate * 3) / 4); // inf, inf or sup, sup: 1/2 + 1/4
} else if (log2Decim == 3) {
return sign * ((halfSampleRate * 5) / 8); // inf, inf, sup or sup, sup, inf: 1/2 + 1/4 - 1/8 = 5/8
} else if (log2Decim == 4) {
return sign * ((halfSampleRate * 11) / 16); // inf, inf, sup, inf or sup, sup, inf, sup: 1/2 + 1/4 - 1/8 + 1/16 = 11/16
} else if (log2Decim == 5) {
return sign * ((halfSampleRate * 21) / 32); // inf, inf, sup, inf, sup or sup, sup, inf, sup, inf: 1/2 + 1/4 - 1/8 + 1/16 - 1/32 = 21/32
} else if (log2Decim == 6) {
return sign * ((halfSampleRate * 21) / 64); // inf, sup, inf, sup, inf, sup or sup, inf, sup, inf, sup, inf: 1/2 - 1/4 + 1/8 -1/16 + 1/32 - 1/64 = 21/64
} else {
return 0;
}
}
}
int64_t DeviceSampleStatic::calculateSinkDeviceCenterFrequency(
uint64_t centerFrequency,
int64_t transverterDeltaFrequency,
int log2Interp,
fcPos_t fcPos,
uint32_t devSampleRate,
bool transverterMode)
{
int64_t deviceCenterFrequency = centerFrequency;
deviceCenterFrequency -= transverterMode ? transverterDeltaFrequency : 0;
deviceCenterFrequency = deviceCenterFrequency < 0 ? 0 : deviceCenterFrequency;
int64_t f_img = deviceCenterFrequency;
deviceCenterFrequency -= calculateSinkFrequencyShift(log2Interp, fcPos, devSampleRate);
f_img -= 2*calculateSinkFrequencyShift(log2Interp, fcPos, devSampleRate);
qDebug() << "DeviceSampleStatic::calculateSinkDeviceCenterFrequency:"
<< " desired center freq: " << centerFrequency << " Hz"
<< " device center freq: " << deviceCenterFrequency << " Hz"
<< " device sample rate: " << devSampleRate << "S/s"
<< " Actual sample rate: " << devSampleRate/(1<<log2Interp) << "S/s"
<< " center freq position code: " << fcPos
<< " image frequency: " << f_img << "Hz";
return deviceCenterFrequency;
}
int64_t DeviceSampleStatic::calculateSinkCenterFrequency(
uint64_t deviceCenterFrequency,
int64_t transverterDeltaFrequency,
int log2Interp,
fcPos_t fcPos,
uint32_t devSampleRate,
bool transverterMode)
{
int64_t centerFrequency = deviceCenterFrequency;
centerFrequency += calculateSinkFrequencyShift(log2Interp, fcPos, devSampleRate);
centerFrequency += transverterMode ? transverterDeltaFrequency : 0;
centerFrequency = centerFrequency < 0 ? 0 : centerFrequency;
qDebug() << "DeviceSampleStatic::calculateSinkCenterFrequency:"
<< " desired center freq: " << centerFrequency << " Hz"
<< " device center freq: " << deviceCenterFrequency << " Hz"
<< " device sample rate: " << devSampleRate << "S/s"
<< " Actual sample rate: " << devSampleRate/(1<<log2Interp) << "S/s"
<< " center freq position code: " << fcPos;
return centerFrequency;
}
/**
* log2Interp = 0: no shift
*
* log2Interp = 1: middle of side band (inf or sup: 1/2)
* ^ | ^
* | inf | inf | sup | sup |
*
* log2Interp = 2: middle of far side half side band (inf, inf or sup, sup: 1/2 + 1/4)
* ^ | ^
* | inf | inf | sup | sup |
*
* log2Interp = 3: inf, inf, sup or sup, sup, inf: 1/2 + 1/4 - 1/8 = 5/8
* log2Interp = 4: inf, inf, sup, inf or sup, sup, inf, sup: 1/2 + 1/4 - 1/8 + 1/16 = 11/16
* log2Interp = 5: inf, inf, sup, inf, sup or sup, sup, inf, sup, inf: 1/2 + 1/4 - 1/8 + 1/16 - 1/32 = 21/32
* log2Interp = 6: inf, sup, inf, sup, inf, sup or sup, inf, sup, inf, sup, inf: 1/2 - 1/4 + 1/8 -1/16 + 1/32 - 1/64 = 21/64
*
*/
int DeviceSampleStatic::calculateSinkFrequencyShift(
int log2Interp,
fcPos_t fcPos,
uint32_t devSampleRate)
{
if (fcPos == FC_POS_CENTER) {
return 0;
}
int sign = fcPos == FC_POS_INFRA ? -1 : 1;
int halfSampleRate = devSampleRate / 2; // fractions are relative to sideband thus based on half the sample rate
if (log2Interp == 0) {
return 0;
} else if (log2Interp == 1) {
return sign * (halfSampleRate / 2);
} else if (log2Interp == 2) {
return sign * ((halfSampleRate * 3) / 4);
} else if (log2Interp == 3) {
return sign * ((halfSampleRate * 5) / 8);
} else if (log2Interp == 4) {
return sign * ((halfSampleRate * 11) / 16);
} else if (log2Interp == 5) {
return sign * ((halfSampleRate * 21) / 32);
} else if (log2Interp == 6) {
return sign * ((halfSampleRate * 21) / 64);
} else {
return 0;
}
}