Add chirp corrector class

BatchDrake · May 5, 2023 · f39e084 · f39e084
1 parent 36b751a
commit f39e084
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Showing 3 changed files with 217 additions and 0 deletions.
diff --git a/AmateurDSN.pro b/AmateurDSN.pro
@@ -32,6 +32,7 @@ isEmpty(SIGDIGGER_PREFIX) {
 #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
 
 SOURCES += \
+    ChirpCorrector.cpp \
     ExternalTool.cpp \
     ExternalToolFactory.cpp \
     ForwarderWidget.cpp \
@@ -60,6 +61,7 @@ FORMS += \
   SNRTool.ui
 
 HEADERS += \
+  ChirpCorrector.h \
   ExternalTool.h \
   ExternalToolFactory.h \
   ForwarderWidget.h \

diff --git a/ChirpCorrector.cpp b/ChirpCorrector.cpp
@@ -0,0 +1,143 @@
+//
+//    ChirpCorrector.cpp: Chirp corrector
+//    Copyright (C) 2023 Gonzalo José Carracedo Carballal
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Lesser General Public License as
+//    published by the Free Software Foundation, either 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 Lesser General Public License for more details.
+//
+//    You should have received a copy of the GNU Lesser General Public
+//    License along with this program.  If not, see
+//    <http://www.gnu.org/licenses/>
+//
+#include "ChirpCorrector.h"
+#include <SuWidgetsHelpers.h>
+
+using namespace SigDigger;
+
+SUBOOL
+onChirpCorrectorBaseBandData(
+    void *privdata,
+    suscan_analyzer_t *,
+    SUCOMPLEX *samples,
+    SUSCOUNT length)
+{
+  ChirpCorrector *corrector = reinterpret_cast<ChirpCorrector *>(privdata);
+
+  corrector->process(samples, length);
+
+  return SU_TRUE;
+}
+
+ChirpCorrector::ChirpCorrector()
+{
+  su_ncqo_init(&m_ncqo, 0);
+}
+
+void
+ChirpCorrector::refreshCorrector()
+{
+  if (m_doReset) {
+    m_currOmega = 0;
+    m_doReset = false;
+  }
+
+  if (m_doNewRate) {
+    SUDOUBLE chirpRatePerSample;
+    SUDOUBLE sampRate = SCAST(SUDOUBLE, m_analyzer->getSampleRate());
+    m_chirpRate = m_desiredRate;
+
+    chirpRatePerSample = m_chirpRate / sampRate;
+    m_deltaOmega =  -SCAST(
+          SUDOUBLE,
+          SU_NORM2ANG_FREQ(SU_ABS2NORM_FREQ(sampRate, chirpRatePerSample)));
+
+    m_doNewRate = false;
+  }
+}
+
+void
+ChirpCorrector::process(SUCOMPLEX *samples, SUSCOUNT length)
+{
+  if (m_enabled) {
+    SUSCOUNT i;
+    SUDOUBLE currOmega, deltaOmega;
+
+    refreshCorrector();
+
+    currOmega  = m_currOmega;
+    deltaOmega = m_deltaOmega;
+
+    for (i = 0; i < length; ++i) {
+      currOmega += deltaOmega;
+      if (currOmega > M_PI)
+        currOmega -= 2 * M_PI;
+      else if (currOmega < -M_PI)
+        currOmega += 2 * M_PI;
+
+      su_ncqo_set_angfreq(&m_ncqo, SU_ASFLOAT(currOmega));
+      samples[i] *= su_ncqo_read(&m_ncqo);
+    }
+
+    m_currOmega = currOmega;
+  }
+}
+
+void
+ChirpCorrector::ensureCorrector()
+{
+  if (m_analyzer != nullptr) {
+    if (m_enabled && !m_installed) {
+      m_doNewRate = true;
+      m_doReset = true;
+      m_analyzer->registerBaseBandFilter(
+            onChirpCorrectorBaseBandData,
+            this,
+            AMATEUR_DSN_CHIRP_CORRECTOR_PRIO);
+      m_installed = true;
+    }
+  }
+}
+
+void
+ChirpCorrector::setAnalyzer(Suscan::Analyzer *analyzer)
+{
+  if (analyzer != m_analyzer)
+    m_installed = false;
+
+  m_analyzer = analyzer;
+
+  ensureCorrector();
+}
+
+void
+ChirpCorrector::setEnabled(bool enabled)
+{
+  m_enabled = enabled;
+  ensureCorrector();
+}
+
+void
+ChirpCorrector::setChirpRate(SUDOUBLE rate)
+{
+  m_desiredRate = rate;
+  m_doNewRate = true;
+
+}
+
+void
+ChirpCorrector::reset()
+{
+  m_doReset = true;
+}
+
+ChirpCorrector::~ChirpCorrector()
+{
+  // We do not need this for now
+}
diff --git a/ChirpCorrector.h b/ChirpCorrector.h
@@ -0,0 +1,72 @@
+//
+//    ChirpCorrector.h: Chirp corrector
+//    Copyright (C) 2023 Gonzalo José Carracedo Carballal
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Lesser General Public License as
+//    published by the Free Software Foundation, either 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 Lesser General Public License for more details.
+//
+//    You should have received a copy of the GNU Lesser General Public
+//    License along with this program.  If not, see
+//    <http://www.gnu.org/licenses/>
+//
+#ifndef CHIRPCORRECTOR_H
+#define CHIRPCORRECTOR_H
+
+#include <Suscan/Library.h>
+#include <Suscan/Analyzer.h>
+
+#define AMATEUR_DSN_CHIRP_CORRECTOR_PRIO -0x1000
+
+SUBOOL onChirpCorrectorBaseBandData(
+    void *privdata,
+    suscan_analyzer_t *,
+    SUCOMPLEX *samples,
+    SUSCOUNT length);
+
+namespace SigDigger {
+  class ChirpCorrector
+  {
+    Suscan::Analyzer *m_analyzer = nullptr;
+    SUDOUBLE  m_chirpRate = 0;
+    SUDOUBLE  m_deltaOmega = 0;
+    SUDOUBLE  m_currOmega = 0;
+    SUSCOUNT  m_sampCount = 0;
+
+    bool      m_doNewRate = false;
+    bool      m_doReset = false;
+
+    SUDOUBLE  m_desiredRate = 0;
+    bool      m_enabled = false;
+    bool      m_installed = false;
+    su_ncqo_t m_ncqo;
+
+    void ensureCorrector();
+    void refreshCorrector();
+    void process(SUCOMPLEX *samples, SUSCOUNT length);
+
+    friend SUBOOL
+    ::onChirpCorrectorBaseBandData(
+        void *privdata,
+        suscan_analyzer_t *,
+        SUCOMPLEX *samples,
+        SUSCOUNT length);
+
+  public:
+    ChirpCorrector();
+    ~ChirpCorrector();
+
+    void setAnalyzer(Suscan::Analyzer *);
+    void setEnabled(bool);
+    void setChirpRate(SUDOUBLE rate);
+    void reset();
+  };
+}
+
+#endif // CHIRPCORRECTOR_H