From 3a069e47a32a7c2ece12b7a010c4ba9f386da467 Mon Sep 17 00:00:00 2001
From: Joe Taylor <joe@princeton.edu>
Date: Mon, 26 Sep 2022 08:07:11 -0400
Subject: [PATCH] Work in progress on Echo-mode averaging.

---
 lib/avecho.f90         | 28 ++++++++++++++++++++++------
 widgets/mainwindow.cpp |  5 +++--
 2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/lib/avecho.f90 b/lib/avecho.f90
index a74c4b8ea..6db53f100 100644
--- a/lib/avecho.f90
+++ b/lib/avecho.f90
@@ -1,4 +1,4 @@
-subroutine avecho(id2,ndop,nfrit,nauto,nqual,f1,xlevel,snrdb,snrdb0,   &
+subroutine avecho(id2,ndop,nfrit,nauto,navg,nqual,f1,xlevel,snrdb,snrdb0,   &
      db_err,dfreq,width,bDiskData)
 
   integer TXLENGTH
@@ -8,6 +8,8 @@ subroutine avecho(id2,ndop,nfrit,nauto,nqual,f1,xlevel,snrdb,snrdb0,   &
   integer*2 id2(34560)                 !Buffer for Rx data
   real sa(NZ)      !Avg spectrum relative to initial Doppler echo freq
   real sb(NZ)      !Avg spectrum with Dither and changing Doppler removed
+  real, dimension (:,:), allocatable :: sax
+  real, dimension (:,:), allocatable :: sbx
   real red0(NZ)
   real blue0(NZ)
   integer nsum       !Number of integrations
@@ -22,8 +24,18 @@ subroutine avecho(id2,ndop,nfrit,nauto,nqual,f1,xlevel,snrdb,snrdb0,   &
   equivalence (x,c),(ipk,ipkv)
   common/echocom/nclearave,nsum,blue(NZ),red(NZ)
   common/echocom2/fspread_self,fspread_dx
-  save dop0,sa,sb
+  data navg0/-1/
+  save dop0,navg0,sax,sbx
 
+  if(navg.ne.navg0) then
+     if(allocated(sax)) deallocate(sax)
+     if(allocated(sbx)) deallocate(sbx)
+     allocate(sax(1:navg,1:NZ))
+     allocate(sbx(1:navg,1:NZ))
+     nsum=0
+     navg0=navg
+  endif
+  
   fspread=fspread_dx                !### Use the predicted Doppler spread ###
   if(bDiskData) fspread=width
   if(nauto.eq.1) fspread=fspread_self
@@ -46,8 +58,8 @@ subroutine avecho(id2,ndop,nfrit,nauto,nqual,f1,xlevel,snrdb,snrdb0,   &
   if(nclearave.ne.0) nsum=0
   if(nsum.eq.0) then
      dop0=dop                             !Remember the initial Doppler
-     sa=0.                                !Clear the average arrays
-     sb=0.
+     sax=0.                               !Clear the average arrays
+     sbx=0.
   endif
 
   x(TXLENGTH+1:)=0.
@@ -69,10 +81,14 @@ subroutine avecho(id2,ndop,nfrit,nauto,nqual,f1,xlevel,snrdb,snrdb0,   &
   endif
 
   nsum=nsum+1
+  j=mod(nsum-1,navg)+1
   do i=1,NZ
-     sa(i)=sa(i) + s(ia+i-2048)    !Center at initial doppler freq
-     sb(i)=sb(i) + s(ib+i-2048)    !Center at expected echo freq
+     sax(j,i)=s(ia+i-2048)    !Center at initial doppler freq
+     sbx(j,i)=s(ib+i-2048)    !Center at expected echo freq
+     sa(i)=sum(sax(1:navg,i))
+     sb(i)=sum(sbx(1:navg,i))
   enddo
+  
   call echo_snr(s(ia-2047),s(ib-2047),fspread,blue0,red0,snrdb0,   &
        db_err,dfreq,snr_detect)
   call echo_snr(sa,sb,fspread,blue,red,snrdb,db_err,dfreq,snr_detect)
diff --git a/widgets/mainwindow.cpp b/widgets/mainwindow.cpp
index c8ae8d992..d55547ca0 100644
--- a/widgets/mainwindow.cpp
+++ b/widgets/mainwindow.cpp
@@ -155,7 +155,7 @@ extern "C" {
 
   void save_echo_params_(int* ndoptotal, int* ndop, int* nfrit, float* f1, float* fspread, short id2[], int* idir);
 
-  void avecho_( short id2[], int* dop, int* nfrit, int* nauto, int* nqual, float* f1,
+  void avecho_( short id2[], int* dop, int* nfrit, int* nauto, int* navg, int* nqual, float* f1,
                 float* level, float* sigdb, float* sigdb0, float* snr, float* dfreq,
                 float* width, bool* bDiskData);
 
@@ -1610,11 +1610,12 @@ void MainWindow::dataSink(qint64 frames)
       echocom_.nclearave=m_nclearave;
       int nDop=m_fAudioShift;
       int nDopTotal=m_fDop;
+      int navg=ui->sbEchoAvg->value();
       if(m_diskData) {
         int idir=-1;
         save_echo_params_(&nDopTotal,&nDop,&nfrit,&f1,&width,dec_data.d2,&idir);
       }
-      avecho_(dec_data.d2,&nDop,&nfrit,&nauto,&nqual,&f1,&xlevel,&sigdb,
+      avecho_(dec_data.d2,&nDop,&nfrit,&nauto,&navg,&nqual,&f1,&xlevel,&sigdb,
           &sigdb0,&dBerr,&dfreq,&width,&m_diskData);
       //Don't restart Monitor after an Echo transmission
       if(m_bEchoTxed and !m_auto) {