Transceiver52M/radioInterface.cpp

/*
* Copyright 2008, 2009 Free Software Foundation, Inc.
*
* This software is distributed under the terms of the GNU Affero 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 Affero 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 Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.

*/

#include "radioInterface.h"
#include <Logger.h>

RadioInterface::RadioInterface(RadioDevice *wRadio,
                               int wReceiveOffset,
			       int wRadioOversampling,
			       int wTransceiverOversampling,
			       GSM::Time wStartTime)

{
  underrun = false;
 
  sendCursor = 0; 
  rcvCursor = 0;
  mOn = false;
  
  mRadio = wRadio;
  receiveOffset = wReceiveOffset;
  samplesPerSymbol = wRadioOversampling;
  mClock.set(wStartTime);
  loadTest = false;
  powerScaling = 1.0;
}

RadioInterface::~RadioInterface(void) {
  if (rcvBuffer!=NULL) delete rcvBuffer;
  //mReceiveFIFO.clear();
}

double RadioInterface::fullScaleInputValue(void) {
  return mRadio->fullScaleInputValue();
}

double RadioInterface::fullScaleOutputValue(void) {
  return mRadio->fullScaleOutputValue();
}


void RadioInterface::setPowerAttenuation(double atten)
{
  double rfGain, digAtten;

  rfGain = mRadio->setTxGain(mRadio->maxTxGain() - atten);
  digAtten = atten - mRadio->maxTxGain() + rfGain;

  if (digAtten < 1.0)
    powerScaling = 1.0;
  else
    powerScaling = 1.0/sqrt(pow(10, (digAtten/10.0)));
}

short *RadioInterface::radioifyVector(signalVector &wVector,
                                      short *retVector,
                                      float scale,
                                      bool zeroOut)
{
  signalVector::iterator itr = wVector.begin();
  short *shortItr = retVector;
  if (zeroOut) {
    while (itr < wVector.end()) {
      *shortItr++ = 0;
      *shortItr++ = 0;
      itr++;
    }
  } else if (scale != 1.0) { 
    while (itr < wVector.end()) {
      *shortItr++ = (short) (itr->real() * scale);
      *shortItr++ = (short) (itr->imag() * scale);
      itr++;
    }
  } else {
    while (itr < wVector.end()) {
      *shortItr++ = (short) (itr->real());
      *shortItr++ = (short) (itr->imag());
      itr++;
    }
  }

  return retVector;
}

void RadioInterface::unRadioifyVector(short *shortVector, signalVector& newVector)
{
  
  signalVector::iterator itr = newVector.begin();
  short *shortItr = shortVector;
  while (itr < newVector.end()) {
    *itr++ = Complex<float>(*shortItr,*(shortItr+1));
    shortItr += 2;
  }

}


bool started = false;

void RadioInterface::pushBuffer(void) {

  if (sendCursor < 2*INCHUNK*samplesPerSymbol) return;

  // send resampleVector
  int samplesWritten = mRadio->writeSamples(sendBuffer,
					  INCHUNK*samplesPerSymbol,
					  &underrun,
					  writeTimestamp); 
   
  writeTimestamp += (TIMESTAMP) samplesWritten;

  if (sendCursor > 2*samplesWritten) 
    memcpy(sendBuffer,sendBuffer+samplesWritten*2,sizeof(short)*2*(sendCursor-2*samplesWritten));
  sendCursor = sendCursor - 2*samplesWritten;
}


void RadioInterface::pullBuffer(void)
{
   
  bool localUnderrun;

   // receive receiveVector
  short* shortVector = rcvBuffer+rcvCursor;  
  //LOG(DEBUG) << "Reading USRP samples at timestamp " << readTimestamp;
  int samplesRead = mRadio->readSamples(shortVector,OUTCHUNK*samplesPerSymbol,&overrun,readTimestamp,&localUnderrun);
  underrun |= localUnderrun;
  readTimestamp += (TIMESTAMP) samplesRead;
  while (samplesRead < OUTCHUNK*samplesPerSymbol) {
    int oldSamplesRead = samplesRead;
    samplesRead += mRadio->readSamples(shortVector+2*samplesRead,
				     OUTCHUNK*samplesPerSymbol-samplesRead,
				     &overrun,
				     readTimestamp,
				     &localUnderrun);
    underrun |= localUnderrun;
    readTimestamp += (TIMESTAMP) (samplesRead - oldSamplesRead);
  }
  //LOG(DEBUG) << "samplesRead " << samplesRead;

  rcvCursor += samplesRead*2;

}

bool RadioInterface::tuneTx(double freq)
{
  return mRadio->setTxFreq(freq);
}

bool RadioInterface::tuneRx(double freq)
{
  return mRadio->setRxFreq(freq);
}


void RadioInterface::start()
{
  LOG(INFO) << "starting radio interface...";
  mAlignRadioServiceLoopThread.start((void * (*)(void*))AlignRadioServiceLoopAdapter,
                                     (void*)this);
  writeTimestamp = mRadio->initialWriteTimestamp();
  readTimestamp = mRadio->initialReadTimestamp();
  mRadio->start(); 
  LOG(DEBUG) << "Radio started";
  mRadio->updateAlignment(writeTimestamp-10000); 
  mRadio->updateAlignment(writeTimestamp-10000);

  sendBuffer = new short[2*2*INCHUNK*samplesPerSymbol];
  rcvBuffer = new short[2*2*OUTCHUNK*samplesPerSymbol];
 
  mOn = true;

}

void *AlignRadioServiceLoopAdapter(RadioInterface *radioInterface)
{
  while (1) {
    radioInterface->alignRadio();
    pthread_testcancel();
  }
  return NULL;
}

void RadioInterface::alignRadio() {
  sleep(60);
  mRadio->updateAlignment(writeTimestamp+ (TIMESTAMP) 10000);
}

void RadioInterface::driveTransmitRadio(signalVector &radioBurst, bool zeroBurst) {

  if (!mOn) return;

  radioifyVector(radioBurst, sendBuffer+sendCursor, powerScaling, zeroBurst);

  sendCursor += (radioBurst.size()*2);

  pushBuffer();
}

void RadioInterface::driveReceiveRadio() {

  if (!mOn) return;

  if (mReceiveFIFO.size() > 8) return;

  pullBuffer();

  GSM::Time rcvClock = mClock.get();
  rcvClock.decTN(receiveOffset);
  unsigned tN = rcvClock.TN();
  int rcvSz = rcvCursor/2;
  int readSz = 0;
  const int symbolsPerSlot = gSlotLen + 8;

  // while there's enough data in receive buffer, form received 
  //    GSM bursts and pass up to Transceiver
  // Using the 157-156-156-156 symbols per timeslot format.
  while (rcvSz > (symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol) {
    signalVector rxVector((symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol);
    unRadioifyVector(rcvBuffer+readSz*2,rxVector);
    GSM::Time tmpTime = rcvClock;
    if (rcvClock.FN() >= 0) {
      //LOG(DEBUG) << "FN: " << rcvClock.FN();
      radioVector *rxBurst = NULL;
      if (!loadTest)
        rxBurst = new radioVector(rxVector,tmpTime);
      else {
	if (tN % 4 == 0)
	  rxBurst = new radioVector(*finalVec9,tmpTime);
        else
          rxBurst = new radioVector(*finalVec,tmpTime); 
      }
      mReceiveFIFO.put(rxBurst); 
    }
    mClock.incTN(); 
    rcvClock.incTN();
    //if (mReceiveFIFO.size() >= 16) mReceiveFIFO.wait(8);
    //LOG(DEBUG) << "receiveFIFO: wrote radio vector at time: " << mClock.get() << ", new size: " << mReceiveFIFO.size() ;
    readSz += (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
    rcvSz -= (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;

    tN = rcvClock.TN();
  }

  if (readSz > 0) { 
    memcpy(rcvBuffer,rcvBuffer+2*readSz,sizeof(short)*2*(rcvCursor-readSz));
    rcvCursor = rcvCursor-2*readSz;
  }
}