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+/*
+* Copyright 2008 Free Software Foundation, Inc.
+*
+* This software is distributed under multiple licenses; see the COPYING file in the main directory for licensing information for this specific distribuion.
+*
+* This use of this software may be subject to additional restrictions.
+* See the LEGAL file in the main directory for details.
+
+    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.
+
+*/
+
+
+
+#include "Vector.h"
+#include "Complex.h"
+#include "GSMTransfer.h"
+
+
+using namespace GSM;
+
+/** Indicated signalVector symmetry */
+typedef enum Symmetry {
+  NONE = 0,
+  ABSSYM = 1
+};
+
+/** Convolution type indicator */
+typedef enum ConvType {
+  FULL_SPAN = 0,
+  OVERLAP_ONLY = 1,
+  START_ONLY = 2,
+  WITH_TAIL = 3,
+  NO_DELAY = 4,
+  CUSTOM = 5,
+  UNDEFINED = 255
+};
+
+/** the core data structure of the Transceiver */
+class signalVector: public Vector<complex> 
+{
+
+ private:
+  
+  Symmetry symmetry;   ///< the symmetry of the vector
+  bool realOnly;       ///< true if vector is real-valued, not complex-valued
+  
+ public:
+  
+  /** Constructors */
+  signalVector(int dSize=0, Symmetry wSymmetry = NONE):
+    Vector<complex>(dSize),
+    realOnly(false)
+    { 
+      symmetry = wSymmetry; 
+    };
+    
+  signalVector(complex* wData, size_t start, 
+	       size_t span, Symmetry wSymmetry = NONE):
+    Vector<complex>(NULL,wData+start,wData+start+span),
+    realOnly(false)
+    { 
+      symmetry = wSymmetry; 
+    };
+      
+  signalVector(const signalVector &vec1, const signalVector &vec2):
+    Vector<complex>(vec1,vec2),
+    realOnly(false)
+    { 
+      symmetry = vec1.symmetry; 
+    };
+	
+  signalVector(const signalVector &wVector):
+    Vector<complex>(wVector.size()),
+    realOnly(false)
+    {
+      wVector.copyTo(*this); 
+      symmetry = wVector.getSymmetry();
+    };
+
+  /** symmetry operators */
+  Symmetry getSymmetry() const { return symmetry;};
+  void setSymmetry(Symmetry wSymmetry) { symmetry = wSymmetry;}; 
+
+  /** real-valued operators */
+  bool isRealOnly() const { return realOnly;};
+  void isRealOnly(bool wOnly) { realOnly = wOnly;};
+};
+
+/** Convert a linear number to a dB value */
+float dB(float x);
+
+/** Convert a dB value into a linear value */
+float dBinv(float x);
+
+/** Compute the energy of a vector */
+float vectorNorm2(const signalVector &x);
+
+/** Compute the average power of a vector */
+float vectorPower(const signalVector &x);
+
+/** Setup the signal processing library */
+void sigProcLibSetup(int samplesPerSymbol);
+
+/** Destroy the signal processing library */
+void sigProcLibDestroy(void);
+
+/** 
+ 	Convolve two vectors. 
+	@param a,b The vectors to be convolved.
+	@param c, A preallocated vector to hold the convolution result.
+	@param spanType The type/span of the convolution.
+	@return The convolution result.
+*/
+signalVector* convolve(const signalVector *a,
+		       const signalVector *b,
+		       signalVector *c,
+		       ConvType spanType,
+		       unsigned startIx = 0,
+		       unsigned len = 0);
+
+/** 
+	Generate the GSM pulse. 
+	@param samplesPerSymbol The number of samples per GSM symbol.
+	@param symbolLength The size of the pulse.
+	@return The GSM pulse.
+*/
+signalVector* generateGSMPulse(int samplesPerSymbol,
+			       int symbolLength);
+
+/** 
+        Frequency shift a vector.
+	@param y The frequency shifted vector.
+	@param x The vector to-be-shifted.
+	@param freq The digital frequency shift
+	@param startPhase The starting phase of the oscillator 
+	@param finalPhase The final phase of the oscillator
+	@return The frequency shifted vector.
+*/
+signalVector* frequencyShift(signalVector *y,
+			     signalVector *x,
+			     float freq = 0.0,
+			     float startPhase = 0.0,
+			     float *finalPhase=NULL);
+
+/** 
+        Correlate two vectors. 
+        @param a,b The vectors to be correlated.
+        @param c, A preallocated vector to hold the correlation result.
+        @param spanType The type/span of the correlation.
+        @return The correlation result.
+*/
+signalVector* correlate(signalVector *a,
+			signalVector *b,
+			signalVector *c,
+			ConvType spanType,
+                        bool bReversedConjugated = false,
+			unsigned startIx = 0,
+			unsigned len = 0);
+
+/** Operate soft slicer on real-valued portion of vector */ 
+bool vectorSlicer(signalVector *x);
+
+/** GMSK modulate a GSM burst of bits */
+signalVector *modulateBurst(const BitVector &wBurst,
+			    const signalVector &gsmPulse,
+			    int guardPeriodLength,
+			    int samplesPerSymbol);
+
+/** Sinc function */
+float sinc(float x);
+
+/** Delay a vector */
+void delayVector(signalVector &wBurst,
+		 float delay);
+
+/** Add two vectors in-place */
+bool addVector(signalVector &x,
+	       signalVector &y);
+
+/** Multiply two vectors in-place*/
+bool multVector(signalVector &x,
+                signalVector &y);
+
+/** Generate a vector of gaussian noise */
+signalVector *gaussianNoise(int length,
+                            float variance = 1.0,
+                            complex mean = complex(0.0));
+
+/**
+	Given a non-integer index, interpolate a sample.
+	@param inSig The signal from which to interpolate.
+	@param ix The index.
+	@return The interpolated signal value.
+*/
+complex interpolatePoint(const signalVector &inSig,
+			 float ix);
+
+/**
+	Given a correlator output, locate the correlation peak.
+	@param rxBurst The correlator result.
+	@param peakIndex Pointer to value to receive interpolated peak index.
+	@param avgPower Power to value to receive mean power.
+	@return Peak value.
+*/
+complex peakDetect(const signalVector &rxBurst,
+		   float *peakIndex,
+		   float *avgPwr);
+
+/**
+        Apply a scalar to a vector.
+        @param x The vector of interest.
+        @param scale The scalar.
+*/
+void scaleVector(signalVector &x,
+		 complex scale);
+
+/**      
+        Add a constant offset to a vecotr.
+        @param x The vector of interest.
+        @param offset The offset.
+*/
+void offsetVector(signalVector &x,
+		  complex offset);
+
+/**
+        Generate a modulated GSM midamble, stored within the library.
+        @param gsmPulse The GSM pulse used for modulation.
+        @param samplesPerSymbol The number of samples per GSM symbol.
+        @param TSC The training sequence [0..7]
+        @return Success.
+*/
+bool generateMidamble(signalVector &gsmPulse,
+		      int samplesPerSymbol,
+		      int TSC);
+/**
+        Generate a modulated RACH sequence, stored within the library.
+        @param gsmPulse The GSM pulse used for modulation.
+        @param samplesPerSymbol The number of samples per GSM symbol.
+        @return Success.
+*/
+bool generateRACHSequence(signalVector &gsmPulse,
+			  int samplesPerSymbol);
+
+/**
+        Energy detector, checks to see if received burst energy is above a threshold.
+        @param rxBurst The received GSM burst of interest.
+        @param windowLength The number of burst samples used to compute burst energy
+        @param detectThreshold The detection threshold, a linear value.
+        @param avgPwr The average power of the received burst.
+        @return True if burst energy is above threshold.
+*/
+bool energyDetect(signalVector &rxBurst,
+		  unsigned windowLength,
+                  float detectThreshold,
+                  float *avgPwr = NULL);
+
+/**
+        RACH correlator/detector.
+        @param rxBurst The received GSM burst of interest.
+        @param detectThreshold The threshold that the received burst's post-correlator SNR is compared against to determine validity.
+        @param samplesPerSymbol The number of samples per GSM symbol.
+        @param amplitude The estimated amplitude of received RACH burst.
+        @param TOA The estimate time-of-arrival of received RACH burst.
+        @return True if burst SNR is larger that the detectThreshold value.
+*/
+bool detectRACHBurst(signalVector &rxBurst,
+		     float detectThreshold,
+		     int samplesPerSymbol,
+		     complex *amplitude,
+		     float* TOA);
+
+/**
+        Normal burst correlator, detector, channel estimator.
+        @param rxBurst The received GSM burst of interest.
+ 
+        @param detectThreshold The threshold that the received burst's post-correlator SNR is compared against to determine validity.
+        @param samplesPerSymbol The number of samples per GSM symbol.
+        @param amplitude The estimated amplitude of received TSC burst.
+        @param TOA The estimate time-of-arrival of received TSC burst.
+        @param maxTOA The maximum expected time-of-arrival
+        @param requestChannel Set to true if channel estimation is desired.
+        @param channelResponse The estimated channel.
+        @param channelResponseOffset The time offset b/w the first sample of the channel response and the reported TOA.
+        @return True if burst SNR is larger that the detectThreshold value.
+*/
+bool analyzeTrafficBurst(signalVector &rxBurst,
+			 unsigned TSC,
+			 float detectThreshold,
+			 int samplesPerSymbol,
+			 complex *amplitude,
+			 float *TOA,
+                         unsigned maxTOA,
+                         bool requestChannel = false,
+			 signalVector** channelResponse = NULL,
+			 float *channelResponseOffset = NULL);
+
+/**
+	Decimate a vector.
+        @param wVector The vector of interest.
+        @param decimationFactor The amount of decimation, i.e. the decimation factor.
+        @return The decimated signal vector.
+*/
+signalVector *decimateVector(signalVector &wVector,
+			     int decimationFactor);
+
+/**
+        Demodulates a received burst using a soft-slicer.
+	@param rxBurst The burst to be demodulated.
+        @param gsmPulse The GSM pulse.
+        @param samplesPerSymbol The number of samples per GSM symbol.
+        @param channel The amplitude estimate of the received burst.
+        @param TOA The time-of-arrival of the received burst.
+        @return The demodulated bit sequence.
+*/
+SoftVector *demodulateBurst(signalVector &rxBurst,
+			 const signalVector &gsmPulse,
+			 int samplesPerSymbol,
+			 complex channel,
+			 float TOA);
+
+/**
+        Creates a simple Kaiser-windowed low-pass FIR filter.
+        @param cutoffFreq The digital 3dB bandwidth of the filter.
+        @param filterLen The number of taps in the filter.
+        @param gainDC The DC gain of the filter.
+        @return The desired LPF
+*/
+signalVector *createLPF(float cutoffFreq,
+			int filterLen,
+                        float gainDC = 1.0);
+
+/**
+	Change sampling rate of a vector via polyphase resampling.
+        @param wVector The vector to be resampled.
+        @param P The numerator, i.e. the amount of upsampling.
+        @param Q The denominator, i.e. the amount of downsampling.
+	@param LPF An optional low-pass filter used in the resampling process.
+	@return A vector resampled at P/Q of the original sampling rate.
+*/    
+signalVector *polyphaseResampleVector(signalVector &wVector,
+				      int P, int Q,
+				      signalVector *LPF);
+
+/**
+	Change the sampling rate of a vector via linear interpolation.
+	@param wVector The vector to be resampled.
+	@param expFactor Ratio of new sampling rate/original sampling rate.
+	@param endPoint ???
+	@return A vector resampled a expFactor*original sampling rate.
+*/
+signalVector *resampleVector(signalVector &wVector,
+			     float expFactor,
+			     complex endPoint);
+
+/**
+	Design the necessary filters for a decision-feedback equalizer.
+	@param channelResponse The multipath channel that we're mitigating.
+	@param SNRestimate The signal-to-noise estimate of the channel, a linear value
+	@param Nf The number of taps in the feedforward filter.
+	@param feedForwardFilter The designed feed forward filter.
+	@param feedbackFilter The designed feedback filter.
+	@return True if DFE can be designed.
+*/
+bool designDFE(signalVector &channelResponse,
+	       float SNRestimate,
+	       int Nf,
+	       signalVector **feedForwardFilter,
+	       signalVector **feedbackFilter);
+
+/**
+	Equalize/demodulate a received burst via a decision-feedback equalizer.
+	@param rxBurst The received burst to be demodulated.
+	@param TOA The time-of-arrival of the received burst.
+	@param samplesPerSymbol The number of samples per GSM symbol.
+	@param w The feed forward filter of the DFE.
+	@param b The feedback filter of the DFE.
+	@return The demodulated bit sequence.
+*/
+SoftVector *equalizeBurst(signalVector &rxBurst,
+		       float TOA,
+		       int samplesPerSymbol,
+		       signalVector &w, 
+		       signalVector &b);