Adding in the missing Transceiver52M directory

git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2307 19bc5d8c-e614-43d4-8b26-e1612bc8e597

1 files changed, 1486 insertions, 0 deletions

diff --git a/Transceiver52M/sigProcLib.cpp b/Transceiver52M/sigProcLib.cpp
new file mode 100644
index 0000000..fe09c16
--- /dev/null
+++ b/Transceiver52M/sigProcLib.cpp
@@ -0,0 +1,1486 @@
+/*
+* Copyright 2008 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/>.
+
+*/
+
+
+
+#define NDEBUG
+
+#include "sigProcLib.h"
+#include "GSMCommon.h"
+
+#include <Logger.h>
+
+#define TABLESIZE 1024
+
+/** Lookup tables for trigonometric approximation */
+float cosTable[TABLESIZE+1]; // add 1 element for wrap around
+float sinTable[TABLESIZE+1];
+
+/** Constants */
+static const float M_PI_F = (float)M_PI;
+static const float M_2PI_F = (float)(2.0*M_PI);
+static const float M_1_2PI_F = 1/M_2PI_F;
+
+/** Static vectors that contain a precomputed +/- f_b/4 sinusoid */ 
+signalVector *GMSKRotation = NULL;
+signalVector *GMSKReverseRotation = NULL;
+
+/** Static ideal RACH and midamble correlation waveforms */
+typedef struct {
+  signalVector *sequence;
+  signalVector *sequenceReversedConjugated;
+  float        TOA;
+  complex      gain;
+} CorrelationSequence;
+
+CorrelationSequence *gMidambles[] = {NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL};
+CorrelationSequence *gRACHSequence = NULL;
+
+void sigProcLibDestroy(void) {
+  if (GMSKRotation) {
+    delete GMSKRotation;
+    GMSKRotation = NULL;
+  }
+  if (GMSKReverseRotation) {
+    delete GMSKReverseRotation;
+    GMSKReverseRotation = NULL;
+  }
+  for (int i = 0; i < 8; i++) {
+    if (gMidambles[i]!=NULL) {
+      if (gMidambles[i]->sequence) delete gMidambles[i]->sequence;
+      if (gMidambles[i]->sequenceReversedConjugated) delete gMidambles[i]->sequenceReversedConjugated;
+      delete gMidambles[i];
+      gMidambles[i] = NULL;
+    }
+  }
+  if (gRACHSequence) {
+    if (gRACHSequence->sequence) delete gRACHSequence->sequence;
+    if (gRACHSequence->sequenceReversedConjugated) delete gRACHSequence->sequenceReversedConjugated;
+    delete gRACHSequence;
+    gRACHSequence = NULL;
+  }
+}
+
+
+
+// dB relative to 1.0.
+// if > 1.0, then return 0 dB
+float dB(float x) {
+  
+  float arg = 1.0F;
+  float dB = 0.0F;
+  
+  if (x >= 1.0F) return 0.0F;
+  if (x <= 0.0F) return -200.0F;
+
+  float prevArg = arg;
+  float prevdB = dB;
+  float stepSize = 16.0F;
+  float dBstepSize = 12.0F;
+  while (stepSize > 1.0F) {
+    do {
+      prevArg = arg;
+      prevdB = dB;
+      arg /= stepSize;
+      dB -= dBstepSize;
+    } while (arg > x);
+    arg = prevArg;
+    dB = prevdB;
+    stepSize *= 0.5F;
+    dBstepSize -= 3.0F;
+  }
+ return ((arg-x)*(dB-3.0F) + (x-arg*0.5F)*dB)/(arg - arg*0.5F);
+
+}
+
+// 10^(-dB/10), inverse of dB func.
+float dBinv(float x) {
+  
+  float arg = 1.0F;
+  float dB = 0.0F;
+  
+  if (x >= 0.0F) return 1.0F;
+  if (x <= -200.0F) return 0.0F;
+
+  float prevArg = arg;
+  float prevdB = dB;
+  float stepSize = 16.0F;
+  float dBstepSize = 12.0F;
+  while (stepSize > 1.0F) {
+    do {
+      prevArg = arg;
+      prevdB = dB;
+      arg /= stepSize;
+      dB -= dBstepSize;
+    } while (dB > x);
+    arg = prevArg;
+    dB = prevdB;
+    stepSize *= 0.5F;
+    dBstepSize -= 3.0F;
+  }
+
+  return ((dB-x)*(arg*0.5F)+(x-(dB-3.0F))*(arg))/3.0F;
+
+}
+
+float vectorNorm2(const signalVector &x) 
+{
+  signalVector::const_iterator xPtr = x.begin();
+  float Energy = 0.0;
+  for (;xPtr != x.end();xPtr++) {
+	Energy += xPtr->norm2();
+  }
+  return Energy;
+}
+
+
+float vectorPower(const signalVector &x) 
+{
+  return vectorNorm2(x)/x.size();
+}
+
+/** compute cosine via lookup table */
+float cosLookup(const float x)
+{
+  float arg = x*M_1_2PI_F;
+  while (arg > 1.0F) arg -= 1.0F;
+  while (arg < 0.0F) arg += 1.0F;
+
+  const float argT = arg*((float)TABLESIZE);
+  const int argI = (int)argT;
+  const float delta = argT-argI;
+  const float iDelta = 1.0F-delta;
+  return iDelta*cosTable[argI] + delta*cosTable[argI+1];
+}
+
+/** compute sine via lookup table */
+float sinLookup(const float x) 
+{
+  float arg = x*M_1_2PI_F;
+  while (arg > 1.0F) arg -= 1.0F;
+  while (arg < 0.0F) arg += 1.0F;
+
+  const float argT = arg*((float)TABLESIZE);
+  const int argI = (int)argT;
+  const float delta = argT-argI;
+  const float iDelta = 1.0F-delta;
+  return iDelta*sinTable[argI] + delta*sinTable[argI+1];
+}
+
+
+/** compute e^(-jx) via lookup table. */
+complex expjLookup(float x)
+{
+  float arg = x*M_1_2PI_F;
+  while (arg > 1.0F) arg -= 1.0F;
+  while (arg < 0.0F) arg += 1.0F;
+
+  const float argT = arg*((float)TABLESIZE);
+  const int argI = (int)argT;
+  const float delta = argT-argI;
+  const float iDelta = 1.0F-delta;
+   return complex(iDelta*cosTable[argI] + delta*cosTable[argI+1],
+		   iDelta*sinTable[argI] + delta*sinTable[argI+1]);
+}
+
+/** Library setup functions */
+void initTrigTables() {
+  for (int i = 0; i < TABLESIZE+1; i++) {
+    cosTable[i] = cos(2.0*M_PI*i/TABLESIZE);
+    sinTable[i] = sin(2.0*M_PI*i/TABLESIZE);
+  }
+}
+
+void initGMSKRotationTables(int samplesPerSymbol) {
+  GMSKRotation = new signalVector(157*samplesPerSymbol);
+  GMSKReverseRotation = new signalVector(157*samplesPerSymbol);
+  signalVector::iterator rotPtr = GMSKRotation->begin();
+  signalVector::iterator revPtr = GMSKReverseRotation->begin();
+  float phase = 0.0;
+  while (rotPtr != GMSKRotation->end()) {
+    *rotPtr++ = expjLookup(phase);
+    *revPtr++ = expjLookup(-phase);
+    phase += M_PI_F/2.0F/(float) samplesPerSymbol;
+  }
+}
+
+void sigProcLibSetup(int samplesPerSymbol) {
+  initTrigTables();
+  initGMSKRotationTables(samplesPerSymbol);
+}
+
+void GMSKRotate(signalVector &x) {
+  signalVector::iterator xPtr = x.begin();
+  signalVector::iterator rotPtr = GMSKRotation->begin();
+  if (x.isRealOnly()) {
+    while (xPtr < x.end()) {
+      *xPtr = *rotPtr++ * (xPtr->real());
+      xPtr++;
+    }
+  }
+  else {
+    while (xPtr < x.end()) {
+      *xPtr = *rotPtr++ * (*xPtr);
+      xPtr++;
+    }
+  }
+}
+
+void GMSKReverseRotate(signalVector &x) {
+  signalVector::iterator xPtr= x.begin();
+  signalVector::iterator rotPtr = GMSKReverseRotation->begin();
+  if (x.isRealOnly()) {
+    while (xPtr < x.end()) {
+      *xPtr = *rotPtr++ * (xPtr->real());
+      xPtr++;
+    }
+  }
+  else {
+    while (xPtr < x.end()) {
+      *xPtr = *rotPtr++ * (*xPtr);
+      xPtr++;
+    }
+  }
+}
+
+
+signalVector* convolve(const signalVector *a,
+		       const signalVector *b,
+		       signalVector *c,
+		       ConvType spanType,
+		       unsigned startIx,
+		       unsigned len)
+{
+  if ((a==NULL) || (b==NULL)) return NULL; 
+  int La = a->size();
+  int Lb = b->size();
+
+  int startIndex;
+  unsigned int outSize;
+  switch (spanType) {
+    case FULL_SPAN:
+      startIndex = 0;
+      outSize = La+Lb-1;
+      break;
+    case OVERLAP_ONLY:
+      startIndex = La;
+      outSize = abs(La-Lb)+1;
+      break;
+    case START_ONLY:
+      startIndex = 0;
+      outSize = La;
+      break;
+    case WITH_TAIL:
+      startIndex = Lb;
+      outSize = La;
+      break;
+    case NO_DELAY:
+      if (Lb % 2) 
+	startIndex = Lb/2;
+      else
+	startIndex = Lb/2-1;
+      outSize = La;
+      break;
+    case CUSTOM:
+      startIndex = startIx;
+      outSize = len;
+      break;
+    default:
+      return NULL;
+  }
+
+  
+  if (c==NULL)
+    c = new signalVector(outSize);
+  else if (c->size()!=outSize)
+    return NULL;
+
+  signalVector::const_iterator aStart = a->begin();
+  signalVector::const_iterator bStart = b->begin();
+  signalVector::const_iterator aEnd = a->end();
+  signalVector::const_iterator bEnd = b->end();
+  signalVector::iterator cPtr = c->begin();
+  int t = startIndex;
+  int stopIndex = startIndex + outSize;
+  switch (b->getSymmetry()) {
+  case NONE:
+    {
+      while (t < stopIndex) {
+	signalVector::const_iterator aP = aStart+t;
+	signalVector::const_iterator bP = bStart;
+	if (a->isRealOnly() && b->isRealOnly()) {
+	  float sum = 0.0;
+	  while (bP < bEnd) {
+	    if (aP < aStart) break;
+	    if (aP < aEnd) sum += (aP->real())*(bP->real());
+	    aP--;
+	    bP++;
+	  }
+	  *cPtr++ = sum;
+	}
+	else if (a->isRealOnly()) {
+	  complex sum = 0.0;
+	  while (bP < bEnd) {
+	    if (aP < aStart) break;
+	    if (aP < aEnd) sum += (*bP)*(aP->real());
+	    aP--;
+	    bP++;
+	  }
+	  *cPtr++ = sum;
+	}
+	else if (b->isRealOnly()) {
+	  complex sum = 0.0;
+	  while (bP < bEnd) {
+	    if (aP < aStart) break;
+	    if (aP < aEnd) sum += (*aP)*(bP->real());
+	    aP--;
+	    bP++;
+	  }
+	  *cPtr++ = sum;
+	}
+	else {
+	  complex sum = 0.0;
+	  while (bP < bEnd) {
+	    if (aP < aStart) break;
+	    if (aP < aEnd) sum += (*aP)*(*bP);
+	    aP--;
+	    bP++;
+	  }
+	  *cPtr++ = sum;
+	}
+	t++;
+      }
+    }
+    break;
+  case ABSSYM:
+    {
+      complex sum = 0.0;
+      bool isOdd = (bool) (Lb % 2);
+      if (isOdd) 
+	bEnd = bStart + (Lb+1)/2;
+      else 
+	bEnd = bStart + Lb/2;
+      while (t < stopIndex) {
+	signalVector::const_iterator aP = aStart+t;
+	signalVector::const_iterator aPsym = aP-Lb+1;
+	signalVector::const_iterator bP = bStart;
+	sum = 0.0;
+        if (!b->isRealOnly()) {
+	  while (bP < bEnd) {
+	    if (aP < aStart) break;
+	    if (aP == aPsym)
+	      sum+= (*aP)*(*bP);
+	    else if ((aP < aEnd) && (aPsym >= aStart)) 
+	      sum+= ((*aP)+(*aPsym))*(*bP);
+	    else if (aP < aEnd)
+	      sum += (*aP)*(*bP);
+	    else if (aPsym >= aStart)
+	      sum += (*aPsym)*(*bP);
+	    aP--;
+	    aPsym++;
+	    bP++;
+	  }
+        }
+        else {
+          while (bP < bEnd) {
+            if (aP < aStart) break;
+            if (aP == aPsym)
+              sum+= (*aP)*(bP->real());
+            else if ((aP < aEnd) && (aPsym >= aStart))
+              sum+= ((*aP)+(*aPsym))*(bP->real());
+            else if (aP < aEnd)
+              sum += (*aP)*(bP->real());
+            else if (aPsym >= aStart)
+              sum += (*aPsym)*(bP->real());
+            aP--;
+            aPsym++;
+            bP++;
+          }
+        }
+	*cPtr++ = sum;
+	t++;
+      }
+    }
+    break;
+  default:
+    return NULL;
+    break;
+  }
+    
+    
+  return c;
+}
+
+
+signalVector* generateGSMPulse(int symbolLength,
+			       int samplesPerSymbol)
+{
+
+  int numSamples = samplesPerSymbol*symbolLength + 1;
+  signalVector *x = new signalVector(numSamples);
+  signalVector::iterator xP = x->begin();
+  int centerPoint = (numSamples-1)/2;
+  for (int i = 0; i < numSamples; i++) {
+    float arg = (float) (i-centerPoint)/(float) samplesPerSymbol;
+    *xP++ = 0.96*exp(-1.1380*arg*arg-0.527*arg*arg*arg*arg); // GSM pulse approx.
+  }
+
+  float avgAbsval = sqrtf(vectorNorm2(*x)/samplesPerSymbol);
+  xP = x->begin();
+  for (int i = 0; i < numSamples; i++) 
+    *xP++ /= avgAbsval;
+  x->isRealOnly(true);
+  x->setSymmetry(ABSSYM);
+  return x;
+}
+
+signalVector* frequencyShift(signalVector *y,
+			     signalVector *x,
+			     float freq,
+			     float startPhase,
+			     float *finalPhase)
+{
+
+  if (!x) return NULL;
+ 
+  if (y==NULL) {
+    y = new signalVector(x->size());
+    y->isRealOnly(x->isRealOnly());
+    if (y==NULL) return NULL;
+  }
+
+  if (y->size() < x->size()) return NULL;
+
+  float phase = startPhase;
+  signalVector::iterator yP = y->begin();
+  signalVector::iterator xPEnd = x->end();
+  signalVector::iterator xP = x->begin();
+
+  if (x->isRealOnly()) {
+    while (xP < xPEnd) {
+      (*yP++) = expjLookup(phase)*( (xP++)->real() );
+      phase += freq;
+    }
+  }
+  else {
+    while (xP < xPEnd) {
+      (*yP++) = (*xP++)*expjLookup(phase);
+      phase += freq;
+    }
+  }
+
+
+  if (finalPhase) *finalPhase = phase;
+
+  return y;
+}
+
+signalVector* reverseConjugate(signalVector *b)
+{
+    signalVector *tmp = new signalVector(b->size());
+    tmp->isRealOnly(b->isRealOnly());
+    signalVector::iterator bP = b->begin();
+    signalVector::iterator bPEnd = b->end();
+    signalVector::iterator tmpP = tmp->end()-1;
+    if (!b->isRealOnly()) {
+      while (bP < bPEnd) {
+        *tmpP-- = bP->conj();
+        bP++;
+      }
+    }
+    else {
+      while (bP < bPEnd) {
+        *tmpP-- = bP->real();
+        bP++;
+      }
+    }
+
+    return tmp;
+}
+
+signalVector* correlate(signalVector *a,
+			signalVector *b,
+			signalVector *c,
+			ConvType spanType,
+			bool bReversedConjugated,
+		        unsigned startIx,
+			unsigned len)
+{
+  signalVector *tmp = NULL;
+
+  if (!bReversedConjugated) {
+    tmp = reverseConjugate(b);
+  }
+  else {
+    tmp = b;
+  }
+
+  c = convolve(a,tmp,c,spanType,startIx,len);
+
+  if (!bReversedConjugated) delete tmp;
+
+  return c;
+}
+
+
+/* soft output slicer */
+bool vectorSlicer(signalVector *x) 
+{
+
+  signalVector::iterator xP = x->begin();
+  signalVector::iterator xPEnd = x->end();
+  while (xP < xPEnd) {
+    *xP = (complex) (0.5*(xP->real()+1.0F));
+    if (xP->real() > 1.0) *xP = 1.0;
+    if (xP->real() < 0.0) *xP = 0.0;
+    xP++;
+  }
+  return true;
+}
+  
+signalVector *modulateBurst(const BitVector &wBurst,
+			    const signalVector &gsmPulse,
+			    int guardPeriodLength,
+			    int samplesPerSymbol)
+{
+
+  //static complex staticBurst[157];
+
+  int burstSize = samplesPerSymbol*(wBurst.size()+guardPeriodLength);
+  //signalVector modBurst((complex *) staticBurst,0,burstSize);
+  signalVector modBurst(burstSize);// = new signalVector(burstSize);
+  modBurst.isRealOnly(true);
+  //memset(staticBurst,0,sizeof(complex)*burstSize);
+  modBurst.fill(0.0);
+  signalVector::iterator modBurstItr = modBurst.begin();
+
+#if 0 
+  // if wBurst is already differentially decoded
+  *modBurstItr = 2.0*(wBurst[0] & 0x01)-1.0;
+  signalVector::iterator prevVal = modBurstItr;
+  for (unsigned int i = 1; i < wBurst.size(); i++) {
+    modBurstItr += samplesPerSymbol;
+    if (wBurst[i] & 0x01) 
+      *modBurstItr = *prevVal * complex(0.0,1.0);
+    else
+      *modBurstItr = *prevVal * complex(0.0,-1.0);
+    prevVal = modBurstItr;
+  }
+#else
+  // if wBurst are the raw bits
+  for (unsigned int i = 0; i < wBurst.size(); i++) {
+    *modBurstItr = 2.0*(wBurst[i] & 0x01)-1.0;
+    modBurstItr += samplesPerSymbol;
+  }
+
+  // shift up pi/2
+  // ignore starting phase, since spec allows for discontinuous phase
+  GMSKRotate(modBurst);
+#endif
+  modBurst.isRealOnly(false);
+
+  // filter w/ pulse shape
+  signalVector *shapedBurst = convolve(&modBurst,&gsmPulse,NULL,NO_DELAY);
+
+  //delete modBurst;
+  
+  return shapedBurst;
+
+}
+
+float sinc(float x) 
+{
+  if ((x >= 0.01F) || (x <= -0.01F)) return (sinLookup(x)/x);
+  return 1.0F;
+}
+
+void delayVector(signalVector &wBurst,
+		 float delay)
+{
+  
+  int   intOffset = (int) floor(delay);
+  float fracOffset = delay - intOffset;
+  
+  // do fractional shift first, only do it for reasonable offsets
+  if (fabs(fracOffset) > 1e-2) {
+    // create sinc function
+    signalVector sincVector(21); 
+    sincVector.isRealOnly(true);
+    signalVector::iterator sincBurstItr = sincVector.begin();
+    for (int i = 0; i < 21; i++) 
+      *sincBurstItr++ = (complex) sinc(M_PI_F*(i-10-fracOffset));
+  
+    signalVector shiftedBurst(wBurst.size());
+    convolve(&wBurst,&sincVector,&shiftedBurst,NO_DELAY);
+    wBurst.clone(shiftedBurst);
+  }
+
+  if (intOffset < 0) {
+    intOffset = -intOffset;
+    signalVector::iterator wBurstItr = wBurst.begin();
+    signalVector::iterator shiftedItr = wBurst.begin()+intOffset;
+    while (shiftedItr < wBurst.end())
+      *wBurstItr++ = *shiftedItr++;
+    while (wBurstItr < wBurst.end())
+      *wBurstItr++ = 0.0;
+  }
+  else {
+    signalVector::iterator wBurstItr = wBurst.end()-1;
+    signalVector::iterator shiftedItr = wBurst.end()-1-intOffset;
+    while (shiftedItr >= wBurst.begin())
+      *wBurstItr-- = *shiftedItr--;
+    while (wBurstItr >= wBurst.begin())
+      *wBurstItr-- = 0.0;
+  }
+}
+  
+signalVector *gaussianNoise(int length, 
+			    float variance, 
+			    complex mean)
+{
+
+  signalVector *noise = new signalVector(length);
+  signalVector::iterator nPtr = noise->begin();
+  float stddev = sqrtf(variance);
+  while (nPtr < noise->end()) {
+    float u1 = (float) rand()/ (float) RAND_MAX;
+    while (u1==0.0)
+      u1 = (float) rand()/ (float) RAND_MAX;
+    float u2 = (float) rand()/ (float) RAND_MAX;
+    float arg = 2.0*M_PI*u2;
+    *nPtr = mean + stddev*complex(cos(arg),sin(arg))*sqrtf(-2.0*log(u1));
+    nPtr++;
+  }
+
+  return noise;
+}
+
+complex interpolatePoint(const signalVector &inSig,
+			 float ix)
+{
+  
+  int start = (int) (floor(ix) - 10);
+  if (start < 0) start = 0;
+  int end = (int) (floor(ix) + 11);
+  if ((unsigned) end > inSig.size()-1) end = inSig.size()-1;
+  
+  complex pVal = 0.0;
+  if (!inSig.isRealOnly()) {
+    for (int i = start; i < end; i++) 
+      pVal += inSig[i] * sinc(M_PI_F*(i-ix));
+  }
+  else {
+    for (int i = start; i < end; i++) 
+      pVal += inSig[i].real() * sinc(M_PI_F*(i-ix));
+  }
+   
+  return pVal;
+}
+
+  
+ 
+complex peakDetect(const signalVector &rxBurst,
+		   float *peakIndex,
+		   float *avgPwr) 
+{
+  
+
+  complex maxVal = 0.0;
+  float maxIndex = -1;
+  float sumPower = 0.0;
+
+  for (unsigned int i = 0; i < rxBurst.size(); i++) {
+    float samplePower = rxBurst[i].norm2();
+    if (samplePower > maxVal.real()) {
+      maxVal = samplePower;
+      maxIndex = i;
+    }
+    sumPower += samplePower;
+  }
+
+  // interpolate around the peak
+  // to save computation, we'll use early-late balancing
+  float earlyIndex = maxIndex-1;
+  float lateIndex = maxIndex+1;
+  
+  float incr = 0.5;
+  while (incr > 1.0/1024.0) {
+    complex earlyP = interpolatePoint(rxBurst,earlyIndex);
+    complex lateP =  interpolatePoint(rxBurst,lateIndex);
+    if (earlyP < lateP) 
+      earlyIndex += incr;
+    else if (earlyP > lateP)
+      earlyIndex -= incr;
+    else break;
+    incr /= 2.0;
+    lateIndex = earlyIndex + 2.0;
+  }
+
+  maxIndex = earlyIndex + 1.0;
+  maxVal = interpolatePoint(rxBurst,maxIndex);
+
+  if (peakIndex!=NULL)
+    *peakIndex = maxIndex;
+
+  if (avgPwr!=NULL)
+    *avgPwr = (sumPower-maxVal.norm2()) / (rxBurst.size()-1);
+
+  return maxVal;
+
+}
+
+void scaleVector(signalVector &x,
+		 complex scale)
+{
+  signalVector::iterator xP = x.begin();
+  signalVector::iterator xPEnd = x.end();
+  if (!x.isRealOnly()) {
+    while (xP < xPEnd) {
+      *xP = *xP * scale;
+      xP++;
+    }
+  }
+  else {
+    while (xP < xPEnd) {
+      *xP = xP->real() * scale;
+      xP++;
+    }
+  }
+}
+
+/** in-place conjugation */
+void conjugateVector(signalVector &x)
+{
+  if (x.isRealOnly()) return;
+  signalVector::iterator xP = x.begin();
+  signalVector::iterator xPEnd = x.end();
+  while (xP < xPEnd) {
+    *xP = xP->conj();
+    xP++;
+  }
+}
+
+
+// in-place addition!!
+bool addVector(signalVector &x,
+	       signalVector &y)
+{
+  signalVector::iterator xP = x.begin();
+  signalVector::iterator yP = y.begin();
+  signalVector::iterator xPEnd = x.end();
+  signalVector::iterator yPEnd = y.end();
+  while ((xP < xPEnd) && (yP < yPEnd)) {
+    *xP = *xP + *yP;
+    xP++; yP++;
+  }
+  return true;
+}
+
+// in-place multiplication!!
+bool multVector(signalVector &x,
+                 signalVector &y)
+{
+  signalVector::iterator xP = x.begin();
+  signalVector::iterator yP = y.begin();
+  signalVector::iterator xPEnd = x.end();
+  signalVector::iterator yPEnd = y.end();
+  while ((xP < xPEnd) && (yP < yPEnd)) {
+    *xP = (*xP) * (*yP);
+    xP++; yP++;
+  }
+  return true;
+}
+
+
+void offsetVector(signalVector &x,
+		  complex offset)
+{
+  signalVector::iterator xP = x.begin();
+  signalVector::iterator xPEnd = x.end();
+  if (!x.isRealOnly()) {
+    while (xP < xPEnd) {
+      *xP += offset;
+      xP++;
+    }
+  }
+  else {
+    while (xP < xPEnd) {
+      *xP = xP->real() + offset;
+      xP++;
+    }      
+  }
+}
+
+bool generateMidamble(signalVector &gsmPulse,
+		      int samplesPerSymbol,
+		      int TSC)
+{
+
+  if ((TSC < 0) || (TSC > 7)) 
+    return false;
+
+  if (gMidambles[TSC]) {
+    if (gMidambles[TSC]->sequence!=NULL) delete gMidambles[TSC]->sequence;
+    if (gMidambles[TSC]->sequenceReversedConjugated!=NULL)  delete gMidambles[TSC]->sequenceReversedConjugated;
+  }
+
+  signalVector emptyPulse(1); 
+  *(emptyPulse.begin()) = 1.0;
+
+  // only use middle 16 bits of each TSC
+  signalVector *middleMidamble = modulateBurst(gTrainingSequence[TSC].segment(5,16),
+					 emptyPulse,
+					 0,
+					 samplesPerSymbol);
+  signalVector *midamble = modulateBurst(gTrainingSequence[TSC],
+                                         gsmPulse,
+                                         0,
+                                         samplesPerSymbol);
+  
+  if (midamble == NULL) return false;
+  if (middleMidamble == NULL) return false;
+
+  // NOTE: Because ideal TSC 16-bit midamble is 66 symbols into burst,
+  //       the ideal TSC has an + 180 degree phase shift,
+  //       due to the pi/2 frequency shift, that 
+  //       needs to be accounted for.
+  //       26-midamble is 61 symbols into burst, has +90 degree phase shift.
+  scaleVector(*middleMidamble,complex(-1.0,0.0));
+  scaleVector(*midamble,complex(0.0,1.0));
+
+  signalVector *autocorr = correlate(midamble,middleMidamble,NULL,NO_DELAY);
+  
+  if (autocorr == NULL) return false;
+
+  gMidambles[TSC] = new CorrelationSequence;
+  gMidambles[TSC]->sequence = middleMidamble;
+  gMidambles[TSC]->sequenceReversedConjugated = reverseConjugate(middleMidamble);
+  gMidambles[TSC]->gain = peakDetect(*autocorr,&gMidambles[TSC]->TOA,NULL);
+
+  LOG(DEBUG) << "midamble autocorr: " << *autocorr;
+
+  LOG(DEBUG) << "TOA: " << gMidambles[TSC]->TOA;
+
+  //gMidambles[TSC]->TOA -= 5*samplesPerSymbol;
+
+  delete autocorr;
+  delete midamble;
+
+  return true;
+}
+
+bool generateRACHSequence(signalVector &gsmPulse,
+			  int samplesPerSymbol)
+{
+  
+  if (gRACHSequence) {
+    if (gRACHSequence->sequence!=NULL) delete gRACHSequence->sequence;
+    if (gRACHSequence->sequenceReversedConjugated!=NULL) delete gRACHSequence->sequenceReversedConjugated;
+  }
+
+  signalVector *RACHSeq = modulateBurst(gRACHSynchSequence,
+					gsmPulse,
+					0,
+					samplesPerSymbol);
+
+  assert(RACHSeq);
+
+  signalVector *autocorr = correlate(RACHSeq,RACHSeq,NULL,NO_DELAY);
+
+  assert(autocorr);
+
+  gRACHSequence = new CorrelationSequence;
+  gRACHSequence->sequence = RACHSeq;
+  gRACHSequence->sequenceReversedConjugated = reverseConjugate(RACHSeq);
+  gRACHSequence->gain = peakDetect(*autocorr,&gRACHSequence->TOA,NULL);
+ 
+  delete autocorr;
+
+  return true;
+
+}
+
+				
+bool detectRACHBurst(signalVector &rxBurst,
+		     float detectThreshold,
+		     int samplesPerSymbol,
+		     complex *amplitude,
+		     float* TOA)
+{
+
+  //static complex staticData[500];
+ 
+  //signalVector correlatedRACH(staticData,0,rxBurst.size());
+  signalVector correlatedRACH(rxBurst.size());
+  correlate(&rxBurst,gRACHSequence->sequenceReversedConjugated,&correlatedRACH,NO_DELAY,true);
+
+  float meanPower;
+  complex peakAmpl = peakDetect(correlatedRACH,TOA,&meanPower);
+
+  float valleyPower = 0.0; 
+
+  // check for bogus results
+  if ((*TOA < 0.0) || (*TOA > correlatedRACH.size())) {
+        *amplitude = 0.0;
+	return false;
+  }
+  complex *peakPtr = correlatedRACH.begin() + (int) rint(*TOA);
+
+  LOG(DEBUG) << "RACH corr: " << correlatedRACH;
+
+  float numSamples = 0.0;
+  for (int i = 57*samplesPerSymbol; i <= 107*samplesPerSymbol;i++) {
+    if (peakPtr+i >= correlatedRACH.end())
+      break;
+    valleyPower += (peakPtr+i)->norm2();
+    numSamples++;
+  }
+
+  if (numSamples < 2) {
+        *amplitude = 0.0;
+        return false;
+  }
+
+  float RMS = sqrtf(valleyPower/(float) numSamples)+0.00001;
+  float peakToMean = peakAmpl.abs()/RMS;
+
+  LOG(DEBUG) << "RACH peakAmpl=" << peakAmpl << " RMS=" << RMS << " peakToMean=" << peakToMean;
+  *amplitude = peakAmpl/(gRACHSequence->gain);
+
+  *TOA = (*TOA) - gRACHSequence->TOA - 8*samplesPerSymbol;
+
+  LOG(DEBUG) << "RACH thresh: " << peakToMean;
+
+  return (peakToMean > detectThreshold);
+}
+
+bool energyDetect(signalVector &rxBurst,
+		  unsigned windowLength,
+		  float detectThreshold,
+                  float *avgPwr)
+{
+
+  signalVector::const_iterator windowItr = rxBurst.begin(); //+rxBurst.size()/2 - 5*windowLength/2;
+  float energy = 0.0;
+  if (windowLength < 0) windowLength = 20;
+  if (windowLength > rxBurst.size()) windowLength = rxBurst.size();
+  for (unsigned i = 0; i < windowLength; i++) {
+    energy += windowItr->norm2();
+    windowItr+=4;
+  }
+  if (avgPwr) *avgPwr = energy/windowLength;
+  LOG(DEBUG) << "detected energy: " << energy/windowLength;
+  return (energy/windowLength > detectThreshold*detectThreshold);
+}
+  
+
+bool analyzeTrafficBurst(signalVector &rxBurst,
+			 unsigned TSC,
+			 float detectThreshold,
+			 int samplesPerSymbol,
+			 complex *amplitude,
+			 float *TOA,
+			 unsigned maxTOA,
+                         bool requestChannel,
+                         signalVector **channelResponse,
+			 float *channelResponseOffset) 
+{
+
+  assert(TSC<8);
+  assert(amplitude);
+  assert(TOA);
+  assert(gMidambles[TSC]);
+
+  if (maxTOA < 3*samplesPerSymbol) maxTOA = 3*samplesPerSymbol;
+  unsigned spanTOA = maxTOA;
+  if (spanTOA < 5*samplesPerSymbol) spanTOA = 5*samplesPerSymbol;
+
+  unsigned startIx = (66-spanTOA)*samplesPerSymbol;
+  unsigned endIx = (66+16+spanTOA)*samplesPerSymbol;
+  unsigned windowLen = endIx - startIx;
+  unsigned corrLen = 2*maxTOA+1;
+
+  unsigned expectedTOAPeak = (unsigned) round(gMidambles[TSC]->TOA + (gMidambles[TSC]->sequenceReversedConjugated->size()-1)/2);
+
+  signalVector burstSegment(rxBurst.begin(),startIx,windowLen);
+
+  //static complex staticData[200];
+  //signalVector correlatedBurst(staticData,0,corrLen);
+  signalVector correlatedBurst(corrLen);
+  correlate(&burstSegment, gMidambles[TSC]->sequenceReversedConjugated,
+					    &correlatedBurst, CUSTOM,true,
+					    expectedTOAPeak-maxTOA,corrLen);
+
+  float meanPower;
+  *amplitude = peakDetect(correlatedBurst,TOA,&meanPower);
+  float valleyPower = 0.0; //amplitude->norm2();
+  complex *peakPtr = correlatedBurst.begin() + (int) rint(*TOA);
+
+  // check for bogus results
+  if ((*TOA < 0.0) || (*TOA > correlatedBurst.size())) {
+        *amplitude = 0.0;
+        return false;
+  }
+
+  int numRms = 0;
+  for (int i = 2*samplesPerSymbol; i <= 5*samplesPerSymbol;i++) {
+    if (peakPtr - i >= correlatedBurst.begin()) { 
+      valleyPower += (peakPtr-i)->norm2();
+      numRms++;
+    }
+    if (peakPtr + i < correlatedBurst.end()) {
+      valleyPower += (peakPtr+i)->norm2();
+      numRms++;
+    }
+  }
+
+  if (numRms < 2) {
+        // check for bogus results
+        *amplitude = 0.0;
+        return false;
+  }
+
+  float RMS = sqrtf(valleyPower/(float)numRms)+0.00001;
+  float peakToMean = (amplitude->abs())/RMS;
+
+  // NOTE: Because ideal TSC is 66 symbols into burst,
+  //       the ideal TSC has an +/- 180 degree phase shift,
+  //       due to the pi/4 frequency shift, that 
+  //       needs to be accounted for.
+  
+  *amplitude = (*amplitude)/gMidambles[TSC]->gain;
+  *TOA = (*TOA) - (maxTOA); 
+
+  LOG(DEBUG) << "TCH peakAmpl=" << amplitude->abs() << " RMS=" << RMS << " peakToMean=" << peakToMean << " TOA=" << *TOA;
+
+  LOG(DEBUG) << "autocorr: " << correlatedBurst;
+  
+  if (requestChannel && (peakToMean > detectThreshold)) {
+    float TOAoffset = maxTOA; //gMidambles[TSC]->TOA+(66*samplesPerSymbol-startIx);
+    delayVector(correlatedBurst,-(*TOA));
+    // midamble only allows estimation of a 6-tap channel
+    signalVector channelVector(6*samplesPerSymbol);
+    float maxEnergy = -1.0;
+    int maxI = -1;
+    for (int i = 0; i < 7; i++) {
+      if (TOAoffset+(i-5)*samplesPerSymbol + channelVector.size() > correlatedBurst.size()) continue;
+      if (TOAoffset+(i-5)*samplesPerSymbol < 0) continue;
+      correlatedBurst.segmentCopyTo(channelVector,(int) floor(TOAoffset+(i-5)*samplesPerSymbol),channelVector.size());
+      float energy = vectorNorm2(channelVector);
+      if (energy > 0.95*maxEnergy) {
+	maxI = i;
+	maxEnergy = energy;
+      }
+    }
+	
+    *channelResponse = new signalVector(channelVector.size());
+    correlatedBurst.segmentCopyTo(**channelResponse,(int) floor(TOAoffset+(maxI-5)*samplesPerSymbol),(*channelResponse)->size());
+    scaleVector(**channelResponse,complex(1.0,0.0)/gMidambles[TSC]->gain);
+    LOG(DEBUG) << "channelResponse: " << **channelResponse;
+    
+    if (channelResponseOffset) 
+      *channelResponseOffset = 5*samplesPerSymbol-maxI;
+      
+  }
+
+  return (peakToMean > detectThreshold);
+		  
+}
+
+signalVector *decimateVector(signalVector &wVector,
+			     int decimationFactor) 
+{
+  
+  if (decimationFactor <= 1) return NULL;
+
+  signalVector *decVector = new signalVector(wVector.size()/decimationFactor);
+  decVector->isRealOnly(wVector.isRealOnly());
+
+  signalVector::iterator vecItr = decVector->begin();
+  for (unsigned int i = 0; i < wVector.size();i+=decimationFactor) 
+    *vecItr++ = wVector[i];
+
+  return decVector;
+}
+
+
+SoftVector *demodulateBurst(signalVector &rxBurst,
+			 const signalVector &gsmPulse,
+			 int samplesPerSymbol,
+			 complex channel,
+			 float TOA) 
+
+{
+  scaleVector(rxBurst,((complex) 1.0)/channel);
+  delayVector(rxBurst,-TOA);
+
+  signalVector *shapedBurst = &rxBurst;
+
+  // shift up by a quarter of a frequency
+  // ignore starting phase, since spec allows for discontinuous phase
+  GMSKReverseRotate(*shapedBurst);
+
+  // run through slicer
+  if (samplesPerSymbol > 1) {
+     signalVector *decShapedBurst = decimateVector(*shapedBurst,samplesPerSymbol);
+     shapedBurst = decShapedBurst;
+  }
+
+  LOG(DEBUG) << "shapedBurst: " << *shapedBurst;
+
+  vectorSlicer(shapedBurst);
+
+  SoftVector *burstBits = new SoftVector(shapedBurst->size());
+
+  SoftVector::iterator burstItr = burstBits->begin();
+  signalVector::iterator shapedItr = shapedBurst->begin();
+  for (; shapedItr < shapedBurst->end(); shapedItr++) 
+    *burstItr++ = shapedItr->real();
+
+  if (samplesPerSymbol > 1) delete shapedBurst;
+
+  return burstBits;
+
+}
+
+
+// 1.0 is sampling frequency
+// must satisfy cutoffFreq > 1/filterLen
+signalVector *createLPF(float cutoffFreq,
+			int filterLen,
+			float gainDC)
+{
+  
+  signalVector *LPF = new signalVector(filterLen-1);
+  LPF->isRealOnly(true);
+  LPF->setSymmetry(ABSSYM);
+  signalVector::iterator itr = LPF->begin();
+  double sum = 0.0;
+  for (int i = 1; i < filterLen; i++) {
+    float ys = sinc(M_2PI_F*cutoffFreq*((float)i-(float)(filterLen)/2.0F));
+    float yg = 4.0F * cutoffFreq;
+    // Blackman -- less brickwall (sloping transition) but larger stopband attenuation
+    float yw = 0.42 - 0.5*cos(((float)i)*M_2PI_F/(float)(filterLen)) + 0.08*cos(((float)i)*2*M_2PI_F/(float)(filterLen));
+    // Hamming -- more brickwall with smaller stopband attenuation
+    //float yw = 0.53836F - 0.46164F * cos(((float)i)*M_2PI_F/(float)(filterLen+1));
+    *itr++ = (complex) ys*yg*yw;
+    sum += ys*yg*yw;
+  }
+  
+  float normFactor = gainDC/sum; //sqrtf(gainDC/vectorNorm2(*LPF));
+  // normalize power
+  itr = LPF->begin();
+  for (int i = 1; i < filterLen; i++) {
+    *itr = *itr*normFactor;
+    itr++;
+  }
+  return LPF;
+
+}
+    
+
+
+#define POLYPHASESPAN 10
+
+// assumes filter group delay is 0.5*(length of filter)
+signalVector *polyphaseResampleVector(signalVector &wVector,
+				      int P, int Q,
+				      signalVector *LPF)
+
+{
+ 
+  bool deleteLPF = false;
+ 
+  if (LPF==NULL) {
+    float cutoffFreq = (P < Q) ? (1.0/(float) Q) : (1.0/(float) P);
+    LPF = createLPF(cutoffFreq/3.0,100*POLYPHASESPAN+1,Q);
+    deleteLPF = true;
+  }
+
+  signalVector *resampledVector = new signalVector((int) ceil(wVector.size()*(float) P / (float) Q));
+  resampledVector->fill(0);
+  resampledVector->isRealOnly(wVector.isRealOnly());
+  signalVector::iterator newItr = resampledVector->begin();
+
+  //FIXME: need to update for real-only vectors
+  int outputIx = (LPF->size()+1)/2/Q; //((P > Q) ? P : Q); 
+  while (newItr < resampledVector->end()) {
+    int outputBranch = (outputIx*Q) % P; 
+    int inputOffset = (outputIx*Q - outputBranch)/P;
+    signalVector::const_iterator inputItr = wVector.begin() + inputOffset;
+    signalVector::const_iterator filtItr  = LPF->begin() + outputBranch;
+    while (inputItr >= wVector.end()) {
+      inputItr--;
+      filtItr+=P;
+    }
+    complex sum = 0.0;
+    if ((LPF->getSymmetry()!=ABSSYM) || (P>1)) {
+      if (!LPF->isRealOnly()) {
+        while ( (inputItr >= wVector.begin()) && (filtItr < LPF->end()) ) {
+	  sum += (*inputItr)*(*filtItr);
+	  inputItr--;
+	  filtItr += P;
+        }
+      }
+      else {
+        while ( (inputItr >= wVector.begin()) && (filtItr < LPF->end()) ) {
+	  sum += (*inputItr)*(filtItr->real());
+	  inputItr--;
+	  filtItr += P;
+        }
+      }
+    }
+    else {
+      signalVector::const_iterator revInputItr = inputItr- LPF->size() + 1;  
+      signalVector::const_iterator filtMidpoint = LPF->begin()+(LPF->size()-1)/2;
+      if (!LPF->isRealOnly()) {
+	while (filtItr <= filtMidpoint) {
+	  if (inputItr < revInputItr) break;
+	  if (inputItr == revInputItr) 
+	    sum += (*inputItr)*(*filtItr);
+          else if ( (inputItr < wVector.end()) && (revInputItr >= wVector.begin()) )
+            sum += (*inputItr + *revInputItr)*(*filtItr);
+          else if ( inputItr < wVector.end() ) 
+	    sum += (*inputItr)*(*filtItr);
+          else if ( revInputItr >= wVector.begin() )
+	    sum += (*revInputItr)*(*filtItr);
+          inputItr--;
+	  revInputItr++;
+          filtItr++;
+        }
+      }
+      else {
+        while (filtItr <= filtMidpoint) {
+          if (inputItr < revInputItr) break;
+          if (inputItr == revInputItr)
+            sum += (*inputItr)*(filtItr->real());
+          else if ( (inputItr < wVector.end()) && (revInputItr >= wVector.begin()) ) 
+            sum += (*inputItr + *revInputItr)*(filtItr->real());
+          else if ( inputItr < wVector.end() ) 
+            sum += (*inputItr)*(filtItr->real());
+          else if ( revInputItr >= wVector.begin() )
+            sum += (*revInputItr)*(filtItr->real());
+          inputItr--;
+          revInputItr++;
+          filtItr++;
+        }
+      }
+    }
+    *newItr = sum;
+    newItr++;
+    outputIx++;
+  }
+      
+  if (deleteLPF) delete LPF;
+
+  return resampledVector;
+}
+
+
+signalVector *resampleVector(signalVector &wVector,
+			     float expFactor,
+			     complex endPoint)
+
+{
+
+  if (expFactor < 1.0) return NULL;
+
+  signalVector *retVec = new signalVector((int) ceil(wVector.size()*expFactor));
+
+  float t = 0.0;
+  
+  signalVector::iterator retItr = retVec->begin();
+  while (retItr < retVec->end()) {
+    unsigned tLow = (unsigned int) floor(t);
+    unsigned tHigh = tLow + 1;
+    if (tLow > wVector.size()-1) break;
+    if (tHigh > wVector.size()) break;
+    complex lowPoint = wVector[tLow];
+    complex highPoint = (tHigh == wVector.size()) ? endPoint : wVector[tHigh];
+    complex a = (tHigh-t);
+    complex b = (t-tLow);
+    *retItr = (a*lowPoint + b*highPoint);
+    t += 1.0/expFactor;
+  }
+
+  return retVec;
+
+}
+		   
+
+// Assumes symbol-spaced sampling!!!
+// Based upon paper by Al-Dhahir and Cioffi
+bool designDFE(signalVector &channelResponse,
+	       float SNRestimate,
+	       int Nf,
+	       signalVector **feedForwardFilter,
+	       signalVector **feedbackFilter)
+{
+  
+  signalVector G0(Nf);
+  signalVector G1(Nf);
+  signalVector::iterator G0ptr = G0.begin();
+  signalVector::iterator G1ptr = G1.begin();
+  signalVector::iterator chanPtr = channelResponse.begin();
+
+  int nu = channelResponse.size()-1;
+
+  *G0ptr = 1.0/sqrtf(SNRestimate);
+  for(int j = 0; j <= nu; j++) {
+    *G1ptr = chanPtr->conj();
+    G1ptr++; chanPtr++;
+  }
+
+  signalVector *L[Nf];
+  signalVector::iterator Lptr;
+  float d;
+  for(int i = 0; i < Nf; i++) {
+    d = G0.begin()->norm2() + G1.begin()->norm2();
+    L[i] = new signalVector(Nf+nu);
+    Lptr = L[i]->begin()+i;
+    G0ptr = G0.begin(); G1ptr = G1.begin();
+    while ((G0ptr < G0.end()) &&  (Lptr < L[i]->end())) {
+      *Lptr = (*G0ptr*(G0.begin()->conj()) + *G1ptr*(G1.begin()->conj()) )/d;
+      Lptr++;
+      G0ptr++;
+      G1ptr++;
+    }
+    complex k = (*G1.begin())/(*G0.begin());
+
+    if (i != Nf-1) {
+      signalVector G0new = G1;
+      scaleVector(G0new,k.conj());
+      addVector(G0new,G0);
+
+      signalVector G1new = G0;
+      scaleVector(G1new,k*(-1.0));
+      addVector(G1new,G1);
+      delayVector(G1new,-1.0);
+
+      scaleVector(G0new,1.0/sqrtf(1.0+k.norm2()));
+      scaleVector(G1new,1.0/sqrtf(1.0+k.norm2()));
+      G0 = G0new;
+      G1 = G1new;
+    }
+  }
+
+  *feedbackFilter = new signalVector(nu);
+  L[Nf-1]->segmentCopyTo(**feedbackFilter,Nf,nu);
+  scaleVector(**feedbackFilter,(complex) -1.0);
+  conjugateVector(**feedbackFilter);
+
+  signalVector v(Nf);
+  signalVector::iterator vStart = v.begin();
+  signalVector::iterator vPtr;
+  *(vStart+Nf-1) = (complex) 1.0;
+  for(int k = Nf-2; k >= 0; k--) {
+    Lptr = L[k]->begin()+k+1;
+    vPtr = vStart + k+1;
+    complex v_k = 0.0;
+    for (int j = k+1; j < Nf; j++) {
+      v_k -= (*vPtr)*(*Lptr);
+      vPtr++; Lptr++;
+    }
+     *(vStart + k) = v_k;
+  }
+
+  *feedForwardFilter = new signalVector(Nf);
+  signalVector::iterator w = (*feedForwardFilter)->begin();
+  for (int i = 0; i < Nf; i++) {
+    delete L[i];
+    complex w_i = 0.0;
+    int endPt = ( nu < (Nf-1-i) ) ? nu : (Nf-1-i);
+    vPtr = vStart+i;
+    chanPtr = channelResponse.begin();
+    for (int k = 0; k < endPt+1; k++) {
+      w_i += (*vPtr)*(chanPtr->conj());
+      vPtr++; chanPtr++;
+    }
+    *w = w_i/d;
+    w++;
+  }
+
+
+  return true;
+  
+}
+
+// Assumes symbol-rate sampling!!!!
+SoftVector *equalizeBurst(signalVector &rxBurst,
+		       float TOA,
+		       int samplesPerSymbol,
+		       signalVector &w, // feedforward filter
+		       signalVector &b) // feedback filter
+{
+
+  delayVector(rxBurst,-TOA);
+
+  signalVector* postForwardFull = convolve(&rxBurst,&w,NULL,FULL_SPAN);
+
+  signalVector* postForward = new signalVector(rxBurst.size());
+  postForwardFull->segmentCopyTo(*postForward,w.size()-1,rxBurst.size());
+  delete postForwardFull;
+
+  signalVector::iterator dPtr = postForward->begin();
+  signalVector::iterator dBackPtr;
+  signalVector::iterator rotPtr = GMSKRotation->begin();
+  signalVector::iterator revRotPtr = GMSKReverseRotation->begin();
+
+  signalVector *DFEoutput = new signalVector(postForward->size());
+  signalVector::iterator DFEItr = DFEoutput->begin();
+
+  // NOTE: can insert the midamble and/or use midamble to estimate BER
+  for (; dPtr < postForward->end(); dPtr++) {
+    dBackPtr = dPtr-1;
+    signalVector::iterator bPtr = b.begin();
+    while ( (bPtr < b.end()) && (dBackPtr >= postForward->begin()) ) {
+      *dPtr = *dPtr + (*bPtr)*(*dBackPtr);
+      bPtr++;
+      dBackPtr--;
+    }
+    *dPtr = *dPtr * (*revRotPtr);
+    *DFEItr = *dPtr;
+    // make decision on symbol
+    *dPtr = (dPtr->real() > 0.0) ? 1.0 : -1.0;
+    //*DFEItr = *dPtr;
+    *dPtr = *dPtr * (*rotPtr);
+    DFEItr++;
+    rotPtr++;
+    revRotPtr++;
+  }
+
+  vectorSlicer(DFEoutput);
+
+  SoftVector *burstBits = new SoftVector(postForward->size());
+  SoftVector::iterator burstItr = burstBits->begin();
+  DFEItr = DFEoutput->begin();
+  for (; DFEItr < DFEoutput->end(); DFEItr++) 
+    *burstItr++ = DFEItr->real();
+
+  delete postForward;
+
+  delete DFEoutput;
+
+  return burstBits;
+}