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sdrangel/plugins/channelrx/radioclock/radioclocksink.cpp
2024-04-11 23:31:34 +02:00

1038 lines
36 KiB
C++

///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2021-2022 Edouard Griffiths, F4EXB <f4exb06@gmail.com> //
// Copyright (C) 2021-2024 Jon Beniston, M7RCE <jon@beniston.com> //
// //
// 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 <complex.h>
#include "dsp/scopevis.h"
#include "util/db.h"
#include "radioclock.h"
#include "radioclocksink.h"
RadioClockSink::RadioClockSink(RadioClock *radioClock) :
m_scopeSink(nullptr),
m_radioClock(radioClock),
m_channelSampleRate(RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE),
m_channelFrequencyOffset(0),
m_magsq(0.0),
m_magsqSum(0.0),
m_magsqPeak(0.0),
m_magsqCount(0),
m_messageQueueToChannel(nullptr),
m_data(0),
m_prevData(0),
m_sample(0),
m_lowCount(0),
m_highCount(0),
m_periodCount(0),
m_gotMinuteMarker(false),
m_second(0),
m_dst(RadioClockSettings::UNKNOWN),
m_zeroCount(0),
m_sampleBufferIndex(0),
m_gotMarker(false)
{
m_phaseDiscri.setFMScaling(RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE / (2.0f * 20.0/M_PI));
applySettings(m_settings, true);
applyChannelSettings(m_channelSampleRate, m_channelFrequencyOffset, true);
for (int i = 0; i < RadioClockSettings::m_scopeStreams; i++) {
m_sampleBuffer[i].resize(m_sampleBufferSize);
}
}
RadioClockSink::~RadioClockSink()
{
}
void RadioClockSink::setScopeSink(ScopeVis* scopeSink)
{
m_scopeSink = scopeSink;
}
void RadioClockSink::sampleToScope(Complex sample)
{
if (m_scopeSink)
{
m_sampleBuffer[0][m_sampleBufferIndex] = sample;
m_sampleBuffer[1][m_sampleBufferIndex] = Complex(m_magsq, 0.0f);
m_sampleBuffer[2][m_sampleBufferIndex] = Complex(m_threshold, 0.0f);
m_sampleBuffer[3][m_sampleBufferIndex] = Complex(m_fmDemodMovingAverage.asDouble(), 0.0f);
m_sampleBuffer[4][m_sampleBufferIndex] = Complex(m_data, 0.0f);
m_sampleBuffer[5][m_sampleBufferIndex] = Complex(m_sample, 0.0f);
m_sampleBuffer[6][m_sampleBufferIndex] = Complex(m_gotMinuteMarker, 0.0f);
m_sampleBuffer[7][m_sampleBufferIndex] = Complex(m_gotMarker, 0.0f);
m_sampleBufferIndex++;
if (m_sampleBufferIndex == m_sampleBufferSize)
{
std::vector<ComplexVector::const_iterator> vbegin;
for (int i = 0; i < RadioClockSettings::m_scopeStreams; i++) {
vbegin.push_back(m_sampleBuffer[i].begin());
}
m_scopeSink->feed(vbegin, m_sampleBufferSize);
m_sampleBufferIndex = 0;
}
}
}
void RadioClockSink::feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end)
{
Complex ci;
for (SampleVector::const_iterator it = begin; it != end; ++it)
{
Complex c(it->real(), it->imag());
c *= m_nco.nextIQ();
if (m_interpolatorDistance < 1.0f) // interpolate
{
while (!m_interpolator.interpolate(&m_interpolatorDistanceRemain, c, &ci))
{
processOneSample(ci);
m_interpolatorDistanceRemain += m_interpolatorDistance;
}
}
else // decimate
{
if (m_interpolator.decimate(&m_interpolatorDistanceRemain, c, &ci))
{
processOneSample(ci);
m_interpolatorDistanceRemain += m_interpolatorDistance;
}
}
}
}
// Extract binary-coded decimal from time code - LSB first
int RadioClockSink::bcd(int firstBit, int lastBit)
{
const int vals[] = {1, 2, 4, 8, 10, 20, 40, 80};
int idx = 0;
int val = 0;
for (int i = firstBit; i <= lastBit; i++)
{
if (m_timeCode[i]) {
val += vals[idx];
}
idx++;
}
return val;
}
// Extract binary-coded decimal from time code - MSB first
int RadioClockSink::bcdMSB(int firstBit, int lastBit, int skipBit1, int skipBit2)
{
const int vals[] = {1, 2, 4, 8, 10, 20, 40, 80, 100, 200};
int idx = 0;
int val = 0;
for (int i = lastBit; i >= firstBit; i--)
{
if ((i != skipBit1) && (i != skipBit2)) {
if (m_timeCode[i]) {
val += vals[idx];
}
idx++;
}
}
return val;
}
// XOR bits together for parity check
int RadioClockSink::xorBits(int firstBit, int lastBit)
{
int x = 0;
for (int i = firstBit; i <= lastBit; i++)
{
x ^= m_timeCode[i];
}
return x;
}
bool RadioClockSink::evenParity(int firstBit, int lastBit, int parityBit)
{
return xorBits(firstBit, lastBit) == parityBit;
}
bool RadioClockSink::oddParity(int firstBit, int lastBit, int parityBit)
{
return xorBits(firstBit, lastBit) != parityBit;
}
// German DCF77
// https://en.wikipedia.org/wiki/DCF77
void RadioClockSink::dcf77()
{
// DCF77 reduces carrier by -16.5dB
m_threshold = m_thresholdMovingAverage.asDouble() * m_linearThreshold; // xdB below average
m_data = m_magsq > m_threshold;
// Look for minute marker - 59th second carrier is held high
if ((m_data == 0) && (m_prevData == 1))
{
if ( (m_highCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 2)
&& (m_highCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 1.6)
&& (m_lowCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.3)
&& (m_lowCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.1)
)
{
qDebug() << "RadioClockSink::dcf77 - Minute marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount;
if (getMessageQueueToChannel() && !m_gotMinuteMarker) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Got minute marker"));
}
m_periodCount = 0;
m_second = 0;
m_gotMinuteMarker = true;
m_secondMarkers = 1;
}
m_lowCount = 0;
}
else if ((m_data == 1) && (m_prevData == 0))
{
m_highCount = 0;
}
else if (m_data == 1)
{
m_highCount++;
}
else if (m_data == 0)
{
m_lowCount++;
}
m_sample = false;
if (m_gotMinuteMarker)
{
m_periodCount++;
if (m_periodCount == 50)
{
// Check we get second marker
m_secondMarkers += m_data == 0;
// If we see too many 1s instead of 0s, assume we've lost the signal
if ((m_second > 10) && (m_secondMarkers / m_second < 0.7))
{
qDebug() << "RadioClockSink::dcf77 - Lost lock: " << m_secondMarkers << m_second;
m_gotMinuteMarker = false;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
m_sample = true;
}
else if (m_periodCount == 150)
{
// Get data for timecode
m_timeCode[m_second] = !m_data; // No carrier = 1, carrier = 0
m_sample = true;
}
else if (m_periodCount == 950)
{
if (m_second == 59)
{
// Decode timecode to a time and date
int minute = bcd(21, 27);
int hour = bcd(29, 34);
int day = bcd(36, 41);
int month = bcd(45, 49);
int year = 2000 + bcd(50, 57);
QString parityError;
if (!evenParity(21, 27, m_timeCode[28])) {
parityError = "Minute parity error";
}
if (!evenParity(29, 34, m_timeCode[35])) {
parityError = "Hour parity error";
}
if (!evenParity(36, 57, m_timeCode[58])) {
parityError= "Data parity error";
}
// Daylight savings
if (m_timeCode[17] && m_timeCode[16]) {
m_dst = RadioClockSettings::ENDING;
} else if (m_timeCode[17]) {
m_dst = RadioClockSettings::IN_EFFECT;
} else if (m_timeCode[18] && m_timeCode[16]) {
m_dst = RadioClockSettings::STARTING;
} else if (m_timeCode[18]) {
m_dst = RadioClockSettings::NOT_IN_EFFECT;
} else {
m_dst = RadioClockSettings::UNKNOWN;
}
if (parityError.isEmpty())
{
// Bit 17 indicates CEST rather than CET
m_dateTime = QDateTime(QDate(year, month, day), QTime(hour, minute), Qt::OffsetFromUTC, m_timeCode[17] ? 2*3600 : 3600);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("OK"));
}
}
else
{
m_dateTime = m_dateTime.addSecs(1);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create(parityError));
}
}
m_second = 0;
}
else
{
m_second++;
m_dateTime = m_dateTime.addSecs(1);
}
if (getMessageQueueToChannel())
{
RadioClock::MsgDateTime *msg = RadioClock::MsgDateTime::create(m_dateTime, m_dst);
getMessageQueueToChannel()->push(msg);
}
}
else if (m_periodCount == 1000)
{
m_periodCount = 0;
}
}
m_prevData = m_data;
}
// French TDF 162kHz
// https://en.wikipedia.org/wiki/TDF_time_signal
// Uses phase modulation, rather than OOK
void RadioClockSink::tdf(Complex &ci)
{
// FM demodulation
double magsqRaw;
Real deviation;
Real fmDemod = m_phaseDiscri.phaseDiscriminatorDelta(ci, magsqRaw, deviation);
// Filter
m_fmDemodMovingAverage(fmDemod);
// Ternary encoding
Real avg = m_fmDemodMovingAverage.asDouble();
if (avg >= 0.5) {
m_data = 1;
} else if (avg <= -0.5) {
m_data = -1;
} else {
m_data = 0;
}
// Look for minute marker - 59th second is not phase modulated
if ((m_data == 1) && (m_prevData == 0))
{
if ( (m_zeroCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 2)
&& (m_zeroCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 1)
)
{
qDebug() << "RadioClockSink::tdf - Minute marker: (zero " << m_zeroCount << ") prev period " << m_periodCount;
if (getMessageQueueToChannel() && !m_gotMinuteMarker) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Got minute marker"));
}
m_periodCount = 0;
m_second = 0;
m_gotMinuteMarker = true;
m_secondMarkers = 1;
}
}
else if ((m_data == 0) && (m_prevData != 0))
{
m_zeroCount = 0;
}
else if (m_data == 0)
{
m_zeroCount++;
}
m_sample = false;
if (m_gotMinuteMarker)
{
m_periodCount++;
if (m_periodCount == 12)
{
m_bits[0] = m_data;
m_sample = true;
}
else if (m_periodCount == 12+50)
{
m_bits[1] = m_data;
m_sample = true;
}
else if (m_periodCount == 12+100)
{
m_bits[2] = m_data;
m_sample = true;
}
else if (m_periodCount == 12+150)
{
m_bits[3] = m_data;
m_sample = true;
// Check we got second marker
m_secondMarkers += ((m_bits[0] == 1) && (m_bits[1] == -1));
// If too many second markers are missing, assume we've lost the signal
if ((m_second > 10) && (m_secondMarkers / m_second < 0.7))
{
qDebug() << "RadioClockSink::tdf - Lost lock: " << m_secondMarkers << m_second;
m_gotMinuteMarker = false;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
// No phase modulation from 50ms to 150ms is 0, pos then neg is 1
if ((m_bits[2] == 0) && (m_bits[3] == 0)) {
m_timeCode[m_second] = 0;
} else if ((m_bits[2] == 1) && (m_bits[3] == -1)) {
m_timeCode[m_second] = 1;
} else {
//qDebug() << "Unexpected modulation " << m_second;
}
}
else if (m_periodCount == 950)
{
if (m_second == 59)
{
// Decode timecode to time and date
int minute = bcd(21, 27);
int hour = bcd(29, 34);
int day = bcd(36, 41);
int month = bcd(45, 49);
int year = 2000 + bcd(50, 57);
// Daylight savings
if (m_timeCode[17] && m_timeCode[16]) {
m_dst = RadioClockSettings::ENDING;
} else if (m_timeCode[17]) {
m_dst = RadioClockSettings::IN_EFFECT;
} else if (m_timeCode[18] && m_timeCode[16]) {
m_dst = RadioClockSettings::STARTING;
} else if (m_timeCode[18]) {
m_dst = RadioClockSettings::NOT_IN_EFFECT;
} else {
m_dst = RadioClockSettings::UNKNOWN;
}
QString parityError;
if (!evenParity(21, 27, m_timeCode[28])) {
parityError = "Minute parity error";
}
if (!evenParity(29, 34, m_timeCode[35])) {
parityError = "Hour parity error";
}
if (!evenParity(36, 57, m_timeCode[58])) {
parityError= "Data parity error";
}
if (parityError.isEmpty())
{
// Bit 17 indicates CEST rather than CET
m_dateTime = QDateTime(QDate(year, month, day), QTime(hour, minute), Qt::OffsetFromUTC, m_timeCode[17] ? 2*3600 : 3600);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("OK"));
}
}
else
{
m_dateTime = m_dateTime.addSecs(1);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create(parityError));
}
}
m_second = 0;
}
else
{
m_second++;
m_dateTime = m_dateTime.addSecs(1);
}
if (getMessageQueueToChannel())
{
RadioClock::MsgDateTime *msg = RadioClock::MsgDateTime::create(m_dateTime, m_dst);
getMessageQueueToChannel()->push(msg);
}
}
else if (m_periodCount == 1000)
{
m_periodCount = 0;
}
}
m_prevData = m_data;
}
// UK MSF 60kHz
// https://www.npl.co.uk/products-services/time-frequency/msf-radio-time-signal/msf_time_date_code
void RadioClockSink::msf60()
{
m_threshold = m_thresholdMovingAverage.asDouble() * m_linearThreshold; // xdB below average
m_data = m_magsq > m_threshold;
// Look for minute marker - 500ms low, then 500ms high
if ((m_data == 0) && (m_prevData == 1))
{
if ( (m_highCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.6)
&& (m_highCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.4)
&& (m_lowCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.6)
&& (m_lowCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.4)
)
{
qDebug() << "RadioClockSink::msf60 - Minute marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount;
if (getMessageQueueToChannel() && !m_gotMinuteMarker) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Got minute marker"));
}
m_periodCount = 0;
m_second = 1;
m_gotMinuteMarker = true;
m_secondMarkers = 1;
}
m_lowCount = 0;
}
else if ((m_data == 1) && (m_prevData == 0))
{
m_highCount = 0;
}
else if (m_data == 1)
{
m_highCount++;
}
else if (m_data == 0)
{
m_lowCount++;
}
m_sample = false;
if (m_gotMinuteMarker)
{
m_periodCount++;
if (m_periodCount == 50)
{
// Check we get second marker
m_secondMarkers += m_data == 0;
// If we see too many 1s instead of 0s, assume we've lost the signal
if ((m_second > 10) && (m_secondMarkers / m_second < 0.7))
{
qDebug() << "RadioClockSink::msf60 - Lost lock: " << m_secondMarkers << m_second;
m_gotMinuteMarker = false;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
m_sample = true;
}
else if (m_periodCount == 150)
{
// Get data bit A for timecode
m_timeCode[m_second] = !m_data; // No carrier = 1, carrier = 0
m_sample = true;
}
else if (m_periodCount == 250)
{
// Get data bit B for timecode
m_timeCodeB[m_second] = !m_data;
m_sample = true;
}
else if (m_periodCount == 950)
{
if (m_second == 59)
{
// Decode timecode to time and date
int minute = bcdMSB(45, 51);
int hour = bcdMSB(39, 44);
int day = bcdMSB(30, 35);
//int dayOfWeek = bcdMSB(36, 38);
int month = bcdMSB(25, 29);
int year = 2000 + bcdMSB(17, 24);
// Daylight savings
if (m_timeCodeB[58] && m_timeCodeB[53]) {
m_dst = RadioClockSettings::ENDING;
} else if (m_timeCodeB[58]) {
m_dst = RadioClockSettings::IN_EFFECT;
} else if (m_timeCodeB[53]) {
m_dst = RadioClockSettings::STARTING;
} else {
m_dst = RadioClockSettings::NOT_IN_EFFECT;
}
QString parityError;
if (!oddParity(39, 51, m_timeCodeB[57])) {
parityError = "Hour/minute parity error";
}
if (!oddParity(25, 35, m_timeCodeB[55])) {
parityError= "Day/month parity error";
}
if (!oddParity(17, 24, m_timeCodeB[54])) {
parityError = "Hour/minute parity error";
}
if (parityError.isEmpty())
{
// Bit 58B indicates BST rather than GMT
m_dateTime = QDateTime(QDate(year, month, day), QTime(hour, minute), Qt::OffsetFromUTC, m_timeCodeB[58] ? 1*3600 : 0);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("OK"));
}
}
else
{
m_dateTime = m_dateTime.addSecs(1);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create(parityError));
}
}
m_second = 0;
}
else
{
m_second++;
m_dateTime = m_dateTime.addSecs(1);
}
if (getMessageQueueToChannel())
{
RadioClock::MsgDateTime *msg = RadioClock::MsgDateTime::create(m_dateTime, m_dst);
getMessageQueueToChannel()->push(msg);
}
}
else if (m_periodCount == 1000)
{
m_periodCount = 0;
}
}
m_prevData = m_data;
}
// USA WWVB 60kHz
// https://en.wikipedia.org/wiki/WWVB
void RadioClockSink::wwvb()
{
// WWVB reduces carrier by -17dB
// 0.2s reduction is zero bit, 0.5s reduction is one bit
// 0.8s reduction is a marker. Seven markers per minute (0, 9, 19, 29, 39, 49, and 59s) and for leap second
m_threshold = m_thresholdMovingAverage.asDouble() * m_linearThreshold; // xdB below average
m_data = m_magsq > m_threshold;
// Look for minute marker - two consequtive markers
if ((m_data == 0) && (m_prevData == 1))
{
if ( (m_highCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.3)
&& (m_lowCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.7)
)
{
if (m_gotMarker && !m_gotMinuteMarker)
{
qDebug() << "RadioClockSink::wwvb - Minute marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount;
m_gotMinuteMarker = true;
m_second = 1;
m_secondMarkers = 1;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Got minute marker"));
}
}
else
{
qDebug() << "RadioClockSink::wwvb - Marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount << " second " << m_second;
}
m_gotMarker = true;
m_periodCount = 0;
}
else
{
m_gotMarker = false;
}
m_lowCount = 0;
}
else if ((m_data == 1) && (m_prevData == 0))
{
m_highCount = 0;
}
else if (m_data == 1)
{
m_highCount++;
}
else if (m_data == 0)
{
m_lowCount++;
}
m_sample = false;
if (m_gotMinuteMarker)
{
m_periodCount++;
if (m_periodCount == 100)
{
// Check we get second marker
m_secondMarkers += m_data == 0;
// If we see too many 1s instead of 0s, assume we've lost the signal
if ((m_second > 10) && (m_secondMarkers / m_second < 0.7))
{
qDebug() << "RadioClockSink::wwvb - Lost lock: " << m_secondMarkers << m_second;
m_gotMinuteMarker = false;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
m_sample = true;
}
else if (m_periodCount == 350)
{
// Get data bit A for timecode
m_timeCode[m_second] = !m_data; // No carrier = 1, carrier = 0
m_sample = true;
}
else if (m_periodCount == 950)
{
if (m_second == 59)
{
// Check markers are decoded as 1s
const QList<int> markerBits = {9, 19, 29, 39, 49, 59};
int missingMarkers = 0;
for (int i = 0; i < markerBits.size(); i++)
{
if (m_timeCode[markerBits[i]] != 1)
{
missingMarkers++;
qDebug() << "RadioClockSink::wwvb - Missing marker at bit " << markerBits[i];
}
}
if (missingMarkers >= 3)
{
m_gotMinuteMarker = false;
qDebug() << "RadioClockSink::wwvb - Lost lock: Missing markers: " << missingMarkers;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
// Check 0s where expected
const QList<int> zeroBits = {4, 10, 11, 14, 20, 21, 24, 34, 35, 44, 54};
for (int i = 0; i < zeroBits.size(); i++)
{
if (m_timeCode[zeroBits[i]] != 0) {
qDebug() << "RadioClockSink::wwvb - Unexpected 1 at bit " << zeroBits[i];
}
}
// Decode timecode to time and date
int minute = bcdMSB(1, 8, 4);
int hour = bcdMSB(12, 18, 14);
int dayOfYear = bcdMSB(22, 33, 24, 29);
int year = 2000 + bcdMSB(45, 53, 49);
// Daylight savings
int dst = (m_timeCode[57] << 1) | m_timeCode[58];
switch (dst)
{
case 0:
m_dst = RadioClockSettings::NOT_IN_EFFECT;
break;
case 1:
m_dst = RadioClockSettings::ENDING;
break;
case 2:
m_dst = RadioClockSettings::STARTING;
break;
case 3:
m_dst = RadioClockSettings::IN_EFFECT;
break;
}
// Time is UTC
QDate date(year, 1, 1);
date = date.addDays(dayOfYear - 1);
m_dateTime = QDateTime(date, QTime(hour, minute), Qt::OffsetFromUTC, 0);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("OK"));
}
m_second = 0;
}
else
{
m_second++;
m_dateTime = m_dateTime.addSecs(1);
}
if (getMessageQueueToChannel())
{
RadioClock::MsgDateTime *msg = RadioClock::MsgDateTime::create(m_dateTime, m_dst);
getMessageQueueToChannel()->push(msg);
}
}
else if (m_periodCount == 1000)
{
m_periodCount = 0;
}
}
m_prevData = m_data;
}
// Japan JJY 40kHz
// https://en.wikipedia.org/wiki/JJY
void RadioClockSink::jjy()
{
// JJY reduces carrier by -10dB
// Full power, then reduced power, which is the opposite of WWVB
// 0.8s full power is is zero bit, 0.5s full power is one bit
// 0.2s full power is a marker. Seven markers per minute (0, 9, 19, 29, 39, 49, and 59s) and for leap second
m_threshold = m_thresholdMovingAverage.asDouble() * m_linearThreshold; // xdB below average
m_data = m_magsq > m_threshold;
// Look for minute marker - two consequtive markers
if ((m_data == 1) && (m_prevData == 0))
{
if ( (m_highCount <= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.3)
&& (m_lowCount >= RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE * 0.7)
)
{
if (m_gotMarker && !m_gotMinuteMarker)
{
qDebug() << "RadioClockSink::jjy - Minute marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount;
m_gotMinuteMarker = true;
m_second = 1;
m_secondMarkers = 1;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Got minute marker"));
}
}
else
{
qDebug() << "RadioClockSink::jjy - Marker: (low " << m_lowCount << " high " << m_highCount << ") prev period " << m_periodCount << " second " << m_second;
}
m_gotMarker = true;
m_periodCount = 0;
}
else
{
m_gotMarker = false;
}
m_highCount = 0;
}
else if ((m_data == 0) && (m_prevData == 1))
{
m_lowCount = 0;
}
else if (m_data == 1)
{
m_highCount++;
}
else if (m_data == 0)
{
m_lowCount++;
}
m_sample = false;
if (m_gotMinuteMarker)
{
m_periodCount++;
if (m_periodCount == 100)
{
// Check we get second marker
m_secondMarkers += m_data == 1;
// If we see too many 0s instead of 1s, assume we've lost the signal
if ((m_second > 10) && (m_secondMarkers / m_second < 0.7))
{
qDebug() << "RadioClockSink::jjy - Lost lock: " << m_secondMarkers << m_second;
m_gotMinuteMarker = false;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
m_sample = true;
}
else if (m_periodCount == 650)
{
// Get data bit A for timecode
m_timeCode[m_second] = !m_data; // No carrier = 1, carrier = 0
m_sample = true;
}
else if (m_periodCount == 950)
{
if (m_second == 59)
{
// Check markers are decoded as 1s
const QList<int> markerBits = {9, 19, 29, 39, 49, 59};
int missingMarkers = 0;
for (int i = 0; i < markerBits.size(); i++)
{
if (m_timeCode[markerBits[i]] != 1)
{
missingMarkers++;
qDebug() << "RadioClockSink::jjy - Missing marker at bit " << markerBits[i];
}
}
if (missingMarkers >= 3)
{
m_gotMinuteMarker = false;
qDebug() << "RadioClockSink::jjy - Lost lock: Missing markers: " << missingMarkers;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
// Check 0s where expected
const QList<int> zeroBits = {4, 10, 11, 14, 20, 21, 24, 34, 35, 44, 55, 56, 57, 58};
for (int i = 0; i < zeroBits.size(); i++)
{
if (m_timeCode[zeroBits[i]] != 0) {
qDebug() << "RadioClockSink::jjy - Unexpected 1 at bit " << zeroBits[i];
}
}
// Decode timecode to time and date
int minute = bcdMSB(1, 8, 4);
int hour = bcdMSB(12, 18, 14);
int dayOfYear = bcdMSB(22, 33, 24, 29);
int year = 2000 + bcdMSB(41, 48);
// Japan doesn't have daylight savings
m_dst = RadioClockSettings::NOT_IN_EFFECT;
// Time is UTC
QDate date(year, 1, 1);
date = date.addDays(dayOfYear - 1);
m_dateTime = QDateTime(date, QTime(hour, minute), Qt::OffsetFromUTC, 0);
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("OK"));
}
m_second = 0;
}
else
{
m_second++;
m_dateTime = m_dateTime.addSecs(1);
}
if (getMessageQueueToChannel())
{
RadioClock::MsgDateTime *msg = RadioClock::MsgDateTime::create(m_dateTime, m_dst);
getMessageQueueToChannel()->push(msg);
}
}
else if (m_periodCount == 1000)
{
m_periodCount = 0;
}
}
m_prevData = m_data;
}
void RadioClockSink::processOneSample(Complex &ci)
{
// Calculate average and peak levels for level meter
Real re = ci.real() / SDR_RX_SCALEF;
Real im = ci.imag() / SDR_RX_SCALEF;
Real magsq = re*re + im*im;
m_movingAverage(magsq);
m_thresholdMovingAverage(magsq);
m_magsq = m_movingAverage.asDouble();
m_magsqSum += magsq;
if (magsq > m_magsqPeak)
{
m_magsqPeak = magsq;
}
m_magsqCount++;
// Demodulate
if (m_settings.m_modulation == RadioClockSettings::DCF77) {
dcf77();
} else if (m_settings.m_modulation == RadioClockSettings::TDF) {
tdf(ci);
} else if (m_settings.m_modulation == RadioClockSettings::WWVB) {
wwvb();
} else if (m_settings.m_modulation == RadioClockSettings::JJY) {
jjy();
} else {
msf60();
}
// Feed signals to scope
sampleToScope(Complex(re, im));
}
void RadioClockSink::applyChannelSettings(int channelSampleRate, int channelFrequencyOffset, bool force)
{
qDebug() << "RadioClockSink::applyChannelSettings:"
<< " channelSampleRate: " << channelSampleRate
<< " channelFrequencyOffset: " << channelFrequencyOffset;
if ((m_channelFrequencyOffset != channelFrequencyOffset) ||
(m_channelSampleRate != channelSampleRate) || force)
{
m_nco.setFreq(-channelFrequencyOffset, channelSampleRate);
}
if ((m_channelSampleRate != channelSampleRate) || force)
{
m_interpolator.create(16, channelSampleRate, m_settings.m_rfBandwidth / 2.2);
m_interpolatorDistance = (Real) channelSampleRate / (Real) RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE;
m_interpolatorDistanceRemain = m_interpolatorDistance;
}
m_channelSampleRate = channelSampleRate;
m_channelFrequencyOffset = channelFrequencyOffset;
}
void RadioClockSink::applySettings(const RadioClockSettings& settings, bool force)
{
qDebug() << "RadioClockSink::applySettings:"
<< " m_rfBandwidth: " << settings.m_rfBandwidth
<< " m_threshold: " << settings.m_threshold
<< " m_modulation: " << settings.m_modulation
<< " force: " << force;
if ((settings.m_rfBandwidth != m_settings.m_rfBandwidth) || force)
{
m_interpolator.create(16, m_channelSampleRate, settings.m_rfBandwidth / 2.2);
m_interpolatorDistance = (Real) m_channelSampleRate / (Real) RadioClockSettings::RADIOCLOCK_CHANNEL_SAMPLE_RATE;
m_interpolatorDistanceRemain = m_interpolatorDistance;
}
if ((settings.m_threshold != m_settings.m_threshold) || force)
{
m_linearThreshold = CalcDb::powerFromdB(-settings.m_threshold);
}
if ((settings.m_modulation != m_settings.m_modulation) || force)
{
m_gotMinuteMarker = false;
m_lowCount = 0;
m_highCount = 0;
m_zeroCount = 0;
m_second = 0;
m_dst = RadioClockSettings::UNKNOWN;
if (getMessageQueueToChannel()) {
getMessageQueueToChannel()->push(RadioClock::MsgStatus::create("Looking for minute marker"));
}
}
m_settings = settings;
}