1 files changed, 264 insertions, 0 deletions
diff --git a/Transceiver52M/DriveLoop.cpp b/Transceiver52M/DriveLoop.cpp
new file mode 100644
index 0000000..997d009
--- /dev/null
+++ b/Transceiver52M/DriveLoop.cpp
@@ -0,0 +1,264 @@
+/*
+* Copyright 2008, 2009, 2010, 2012 Free Software Foundation, Inc.
+*
+* This software is distributed under the terms of the GNU Public License.
+* See the COPYING file in the main directory for details.
+*
+* This use of this software may be subject to additional restrictions.
+* See the LEGAL file in the main directory for details.
+
+    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, 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 General Public License 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 <stdio.h>
+#include "DriveLoop.h"
+#include <Logger.h>
+
+DriveLoop::DriveLoop(int wSamplesPerSymbol,
+                     GSM::Time wTransmitLatency,
+                     RadioInterface *wRadioInterface)
+{
+  mRadioDriveLoopThread = new Thread(32768);
+
+  mSamplesPerSymbol = wSamplesPerSymbol;
+  mRadioInterface = wRadioInterface;
+
+  GSM::Time startTime(random() % gHyperframe, 0);
+  mTransmitDeadlineClock = startTime;
+  mLatencyUpdateTime = startTime;
+  mTransmitLatency = wTransmitLatency;
+
+  mRadioInterface->getClock()->set(startTime);
+
+  // generate pulse and setup up signal processing library
+  gsmPulse = generateGSMPulse(2, mSamplesPerSymbol);
+  LOG(DEBUG) << "gsmPulse: " << *gsmPulse;
+  sigProcLibSetup(mSamplesPerSymbol);
+
+  txFullScale = mRadioInterface->fullScaleInputValue();
+
+  // initialize filler tables with dummy bursts, initialize other per-timeslot variables
+  for (int i = 0; i < 8; i++) {
+    signalVector* modBurst = modulateBurst(gDummyBurst, *gsmPulse,
+                                           8 + (i % 4 == 0), mSamplesPerSymbol);
+    scaleVector(*modBurst, txFullScale);
+    for (int j = 0; j < 102; j++) {
+      for (int n = 0; n < CHAN_M; n++)
+        fillerTable[n][j][i] = new signalVector(*modBurst);
+    }
+    delete modBurst;
+
+    for (int n = 0; n < CHAN_M; n++) {
+      fillerModulus[n][i] = 26;
+      mChanType[n][i] = NONE;
+    }
+  }
+
+  mOn = false;
+}
+
+DriveLoop::~DriveLoop()
+{
+  delete gsmPulse;
+  sigProcLibDestroy();
+}
+
+void DriveLoop::start()
+{
+  mOn = true;
+  mRadioDriveLoopThread->start((void * (*)(void*))RadioDriveLoopAdapter, (void*) this);
+}
+
+void DriveLoop::pushRadioVector(GSM::Time &nowTime)
+{
+  int i;
+  radioVector *staleBurst;
+  radioVector *next;
+
+  for (i = 0; i < CHAN_M; i++) {
+    // dump stale bursts, if any
+    while (staleBurst = mTransmitPriorityQueue[i].getStaleBurst(nowTime)) {
+      // Even if the burst is stale, put it in the fillter table.
+      // (It might be an idle pattern.)
+      LOG(NOTICE) << "dumping STALE burst in TRX->USRP interface";
+      const GSM::Time& nextTime = staleBurst->getTime();
+      int TN = nextTime.TN();
+      int modFN = nextTime.FN() % fillerModulus[i][TN];
+      delete fillerTable[i][modFN][TN];
+      fillerTable[i][modFN][TN] = staleBurst;
+    }
+
+    int TN = nowTime.TN();
+    int modFN = nowTime.FN() % fillerModulus[i][nowTime.TN()];
+
+    mTxBursts[i] = fillerTable[i][modFN][TN];
+    mIsFiller[i] = true;
+    mIsZero[i] = (mChanType[i][TN] == NONE);
+
+    // if queue contains data at the desired timestamp, stick it into FIFO
+    if (next = (radioVector*) mTransmitPriorityQueue[i].getCurrentBurst(nowTime)) {
+      LOG(DEBUG) << "transmitFIFO: wrote burst " << next << " at time: " << nowTime;
+      delete fillerTable[i][modFN][TN];
+      fillerTable[i][modFN][TN] = new signalVector(*(next));
+      mTxBursts[i] = next;
+      mIsFiller[i] = false;
+    }
+  }
+
+  mRadioInterface->driveTransmitRadio(mTxBursts, mIsZero);
+
+  for (i = 0; i < CHAN_M; i++) {
+    if (!mIsFiller[i])
+      delete mTxBursts[i];
+  }
+}
+
+void DriveLoop::setModulus(int channel, int timeslot)
+{
+  switch (mChanType[channel][timeslot]) {
+  case NONE:
+  case I:
+  case II:
+  case III:
+  case FILL:
+    fillerModulus[channel][timeslot] = 26;
+    break;
+  case IV:
+  case VI:
+  case V:
+    fillerModulus[channel][timeslot] = 51;
+    break;
+    //case V: 
+  case VII:
+    fillerModulus[channel][timeslot] = 102;
+    break;
+  default:
+    break;
+  }
+}
+
+DriveLoop::CorrType DriveLoop::expectedCorrType(int channel, GSM::Time currTime)
+{
+  unsigned burstTN = currTime.TN();
+  unsigned burstFN = currTime.FN();
+
+  switch (mChanType[channel][burstTN]) {
+  case NONE:
+    return OFF;
+    break;
+  case FILL:
+    return IDLE;
+    break;
+  case I:
+    return TSC;
+    /*if (burstFN % 26 == 25) 
+      return IDLE;
+    else
+      return TSC;*/
+    break;
+  case II:
+    if (burstFN % 2 == 1)
+      return IDLE;
+    else
+      return TSC;
+    break;
+  case III:
+    return TSC;
+    break;
+  case IV:
+  case VI:
+    return RACH;
+    break;
+  case V: {
+    int mod51 = burstFN % 51;
+    if ((mod51 <= 36) && (mod51 >= 14))
+      return RACH;
+    else if ((mod51 == 4) || (mod51 == 5))
+      return RACH;
+    else if ((mod51 == 45) || (mod51 == 46))
+      return RACH;
+    else
+      return TSC;
+    break;
+  }
+  case VII:
+    if ((burstFN % 51 <= 14) && (burstFN % 51 >= 12))
+      return IDLE;
+    else
+      return TSC;
+    break;
+  case LOOPBACK:
+    if ((burstFN % 51 <= 50) && (burstFN % 51 >=48))
+      return IDLE;
+    else
+      return TSC;
+    break;
+  default:
+    return OFF;
+    break;
+  }
+}
+   
+void DriveLoop::reset()
+{
+}
+  
+void DriveLoop::driveReceiveFIFO() 
+{
+  SoftVector *rxBurst = NULL;
+  int RSSI;
+  int TOA;  // in 1/256 of a symbol
+  GSM::Time burstTime;
+
+  mRadioInterface->driveReceiveRadio();
+}
+
+/*
+ *  Features a carefully controlled latency mechanism, to
+ *  assure that transmit packets arrive at the radio/USRP
+ *  before they need to be transmitted.
+ *  
+ *  Deadline clock indicates the burst that needs to be
+ *  pushed into the FIFO right NOW.  If transmit queue does
+ *  not have a burst, stick in filler data.
+ */
+void DriveLoop::driveTransmitFIFO() 
+{
+  int i;
+
+  if (!mOn)
+    return;
+
+  RadioClock *radioClock = (mRadioInterface->getClock());
+  while (radioClock->get() + mTransmitLatency > mTransmitDeadlineClock) {
+    pushRadioVector(mTransmitDeadlineClock);
+    mTransmitDeadlineClock.incTN();
+  }
+
+  // FIXME -- This should not be a hard spin.
+  // But any delay here causes us to throw omni_thread_fatal.
+  //else radioClock->wait();
+}
+
+void *RadioDriveLoopAdapter(DriveLoop *transceiver)
+{
+  transceiver->setPriority();
+
+  while (1) {
+    transceiver->driveReceiveFIFO();
+    transceiver->driveTransmitFIFO();
+    pthread_testcancel();
+  }
+  return NULL;
+}