- CPR/STR: no automatic change of ACQ and TRK states base on SNR

- No use for clock stuff, since buffer_ip is decimated
- use Costas Loop for acquisition


git-svn-id: http://moon:8086/svn/software/trunk/projects/mpsk_rx_gui@1052 b431acfa-c32f-4a4a-93f1-934dc6c82436

Source/Receiver.cpp

@@ -345,14 +345,14 @@ void Receiver::timerCallback()
 	}
 
 	// Control
-	m_params.cprState = cpr_state_acquisition;
+//	m_params.cprState = cpr_state_acquisition;
-	m_params.strState = str_state_acquisition;
+//	m_params.strState = str_state_acquisition;
-	if (getStatus().snrCurrent_dB > 30)
+//	if (getStatus().snrCurrent_dB > 30)
-	{
+//	{
 //		statusHasChanged = (m_params.cprState != cpr_state_track) || (m_params.strState != str_state_track);
-		m_params.cprState = cpr_state_track;
+//		m_params.cprState = cpr_state_track;
-		m_params.strState = str_state_track;
+//		m_params.strState = str_state_track;
-	}
+//	}
 
 	// Announce status changed
 	if (statusHasChanged)
@@ -477,32 +477,21 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 		m_polyPhase.process();
 	}
 
-	// Further BB processing
-	// @2 x symbolrate
-	while(m_buffer_ip.len())
-	{
-		ComplexScalar iq_mf = m_buffer_ip.readAt(0);
-
-		// -----------------------------------------------------
-		// Carrier Derotator
-		// @2 x symbolrate
-		// -----------------------------------------------------
-		IQ_cpr = toCpx(m_nco_cpr.mixComplexS(iq_mf, ComplexScalar(1,1)));
-		m_nco_cpr.process(m_dOmega_vco, m_params.CPR_phase);
-
-		IQ_eq_in = IQ_cpr;
-		
 	// -----------------------------------------------------
 	// Big and ugly processing loop
+	// Further BB processing
 	// @1 x symbolrate
 	// -----------------------------------------------------
-		if (ClockIsTick(&m_symClock, 1))
+	while(m_buffer_ip.len())
 	{
+		// Buffer contains every 2nd sample from interpolator
+		ComplexScalar iq_mf = m_buffer_ip.readAt(0);
+
 #ifndef DISABLE_UNUSED_STATISTICS
-			minMaxProcess(&m_statistics.ddcMinMax, IQ_eq_in);
+		minMaxProcess(&m_statistics.ddcMinMax, iq_mf);
 #endif
 		// -----------------------------------------------------
-			// AGC Blind process samples
+		// AGC Tracker based training
 		// @1 x symbolrate
 		// -----------------------------------------------------
 		if (m_params.agc_mode != agc_mode_disabled)
@@ -519,6 +508,22 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 			}
 		}
 
+		// -----------------------------------------------------
+		// Carrier Derotator
+		// @1 x symbolrate
+		// -----------------------------------------------------
+		IQ_cpr = toCpx(m_nco_cpr.mixComplexS(iq_mf, ComplexScalar(1,1)));
+		m_nco_cpr.process(m_dOmega_vco, m_params.CPR_phase);
+
+		// Carrier Phase Recovery
+		if (m_params.cprState == cpr_state_acquisition)
+		{
+			// Costas loop 
+			vPfdCpr = PhaseErrQPSK(IQ_cpr);
+		}
+
+		IQ_eq_in = IQ_cpr;
+
 		// -----------------------------------------------------
 		// Equalizer Process samples
 		// @1 x symbolrate
@@ -552,12 +557,19 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 		IQ_hard = sym_err.hard_sym;
 
 		// Carrier Phase Recovery
-			if (m_params.cpr_mode == cpr_mode_enabled)
+		if (m_params.cprState == cpr_state_track)
 		{
 			// state-based PFD
 			vPfdCpr = PfdProcess(&m_pfdCpr, sym_err.err_phi, dabs(sym_err.mag));
+		}
 
-				// use phase error from symbol mapper
+		if (m_params.cpr_mode == cpr_mode_enabled)
+		{
+			// Update frequency from Carrier Derotator
+			// vPfdCpr comes from PhaseErrQPSK forming a Costas Loop when
+			// cprState == cpr_state_acquisition
+			// vPfdCpr comes from SymMapper forming a decision directed phase correction loop when
+			// cprState == cpr_state_track
 			m_dOmega_vco = LeadLagProcess(&m_loop_filter_cpr, &m_params.cpr_loopfilter_coeff[m_params.cpr_loopfilter_coeff_index], vPfdCpr);
 		}
 
@@ -647,13 +659,11 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 
 		// -----------------------------------------------------
 		m_pSymbolBuffer[m_numSymsInBuffer++] = sym_err;
-			if ((m_params.strState == str_state_track) && (m_params.cprState == cpr_state_track))
-			{
 		// Update per-symbol statistic
 		SymStatUpDate(&m_sym_stat, sym, &sym_err);
 		m_frameReceiver.process((symbol_t)sym);
-			}
 		if (m_pDataListener)
+		{
 			m_pDataListener->receiverDataChanged(this);
 		}
 	}

Source/Receiver.hpp

@@ -306,7 +306,7 @@ class TimingGeneratorGardner : public Interpolation::TimingGenerator
 		coeff = pCoeff;
 	}
 
-	void process(ComplexScalar const &iq)
+	bool process(ComplexScalar const &iq)
 	{
 		// @2 x symbolrate
 		// Symbol timing recovery
@@ -320,6 +320,8 @@ class TimingGeneratorGardner : public Interpolation::TimingGenerator
 		is_time = not is_time;
 
 		update(m_omega);
+
+		return not is_time;
 	}
 };