From 7d7e3326f94a2ef8f5d880e3d94355bb2763e52e Mon Sep 17 00:00:00 2001
From: Jens Ahrensfeld <jens@jayfield.org>
Date: Thu, 16 Jun 2022 19:25:45 +0000
Subject: [PATCH] - moved AGC training to 1 sps loop

git-svn-id: http://moon:8086/svn/software/trunk/projects/mpsk_rx_gui@1007 b431acfa-c32f-4a4a-93f1-934dc6c82436
---
 Source/Receiver.cpp | 47 +++++++++++++++++++++++++++------------------
 1 file changed, 28 insertions(+), 19 deletions(-)

diff --git a/Source/Receiver.cpp b/Source/Receiver.cpp
index ccbfd13..f4b64d7 100644
--- a/Source/Receiver.cpp
+++ b/Source/Receiver.cpp
@@ -453,27 +453,14 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 	}
 #endif
 
-	// Blind AGC
+	// Blind AGC gain adjustment
 	// @2 x symbolrate
-	// AGC Blind Training
 	Processor::Buffer<ComplexScalar> &next_buf_in = m_farrow.getInputBuffer();
-	if (m_params.agc_mode != agc_mode_disabled)
+	for (n = 0; n < len; n++)
 	{
-		for (n = 0; n < len; n++)
-		{
-			// AGC Blind process samples
-			ComplexScalar iq_agc = toComplexScalar(CpxScaleRealS(toCpx(iq[n]), AGC_GetWeight(&agcBlind)));
-			AGC_Process(&agcBlind, CpxMagS(toCpx(iq_agc)), m_params.agcMu[m_params.agcMu_index], m_pSymMapper->R2_cma);
-			next_buf_in.write(&iq_agc, 1);
-		}
-	}
-	else
-	{
-		for (n = 0; n < len; n++)
-		{
-			ComplexScalar iq_agc = toComplexScalar(CpxScaleRealS(toCpx(iq[n]), AGC_GetWeight(&agcBlind)));
-			next_buf_in.write(&iq_agc, 1);
-		}
+		// AGC Blind gain adjustments
+		ComplexScalar iq_agc = toComplexScalar(CpxScaleRealS(toCpx(iq[n]), AGC_GetWeight(&agcBlind)));
+		next_buf_in.write(&iq_agc, 1);
 	}
 
 	// Matched filtering and symbol timing recovery
@@ -503,21 +490,36 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 	{
 		ComplexScalar iq_mf = buf_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;
 		
-		// Operate at symbol clock
+		// -----------------------------------------------------
+		// Big and ugly processing loop
 		// @1 x symbolrate
+		// -----------------------------------------------------
 		if (ClockIsTick(&m_symClock, 1))
 		{
 #ifndef DISABLE_UNUSED_STATISTICS
 			minMaxProcess(&m_statistics.ddcMinMax, IQ_eq_in);
 #endif
+			// -----------------------------------------------------
+			// AGC Blind process samples
+			// @1 x symbolrate
+			// -----------------------------------------------------
+			if (m_params.agc_mode != agc_mode_disabled)
+			{
+				AGC_Process(&agcBlind, CpxMagS(IQ_eq_in), m_params.agcMu[m_params.agcMu_index], m_pSymMapper->R2_cma);
+			}
+
 			// -----------------------------------------------------
 			// Equalizer Process samples
+			// @1 x symbolrate
 			// -----------------------------------------------------
 			ComplexScalar __IQ_cma;
 			ComplexScalar __IQ_dfeOn;
@@ -539,7 +541,10 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 
 			IQ_soft = IQ_eq;
 
+			// -----------------------------------------------------
 			// Map sympol
+			// @1 x symbolrate
+			// -----------------------------------------------------
 			sym = SymMapDemap(m_pSymMapper, IQ_soft);
 			sym_err = SymMapGetError(m_pSymMapper, IQ_soft, sym);
 			IQ_hard = sym_err.hard_sym;
@@ -556,6 +561,7 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 
 			// -----------------------------------------------------
 			// Equalizer Training
+			// @1 x symbolrate
 			// -----------------------------------------------------
 			sym_cma = SymMapGetSymbolInfo(m_pSymMapper, SymMapDemap(m_pSymMapper, IQ_cma));
 			if (m_params.cmaMode == cma_mode_training_enabled)
@@ -607,7 +613,10 @@ void Receiver::processBaseband(CVec const &iq, uint32_t len)
 			// Update IQ_H
 			IQ_hard_last = IQ_hard;
 
+			// -----------------------------------------------------
 			// Lock-detector development
+			// @1 x symbolrate
+			// -----------------------------------------------------
 			cpx_t winner_diff = Cpx(0,0);
 			radio_float_t winner_d = 1000;
 			int winner_i = 0;