From ce7d5b8d0270e7e4a7df456ebee53a88d667bf13 Mon Sep 17 00:00:00 2001
From: Joe Taylor <joe@princeton.edu>
Date: Wed, 14 Feb 2024 11:49:59 -0500
Subject: [PATCH] Simplify a few parts of code used for SuperFox simulations.

---
 lib/superfox/sfox_mod.f90 | 17 +++++++++--------
 lib/superfox/sfoxtest.f90 | 10 +++-------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/lib/superfox/sfox_mod.f90 b/lib/superfox/sfox_mod.f90
index 64cf1c5ec..4c84a9ae4 100644
--- a/lib/superfox/sfox_mod.f90
+++ b/lib/superfox/sfox_mod.f90
@@ -7,24 +7,25 @@ contains
   subroutine sfox_init(mm0,nn0,kk0,itu,fspread,delay)
 
     character*2 itu
-    integer isps(30)
+    integer isps(50)
     integer iloc(1)
-    data isps/1000,1008,1024,1050,1080,1120,1152,1176,1200,1260,   &
-              1280,1296,1344,1350,1372,1400,1440,1470,1500,1512,   &
-              1536,1568,1600,1620,1680,1728,1920,1944,1960,2000/
-
+    data isps/1000,1008,1024,1029,1050,1080,1120,1125,1134,1152,   &
+              1176,1200,1215,1225,1250,1260,1280,1296,1323,1344,   &
+              1350,1372,1400,1440,1458,1470,1500,1512,1536,1568,   &
+              1575,1600,1620,1680,1701,1715,1728,1750,1764,1792,   &
+              1800,1875,1890,1920,1944,1960,2000,2016,2025,2048/
 
     MM=mm0              !Bits per symbol
     NQ=2**MM            !Q, number of MFSK tones
     NN=nn0              !Channel symbols, before puncture
     KK=kk0              !Information symbols, before puncture
     ND1=25              !Data symbols before sync 
-    ND2=NN-2-ND1        !Data symbols after sync 
-    ND=ND1+ND2          !Total data symbols
+    ND2=NN-ND1          !Data symbols after sync 
+    ND=NN               !Total data symbols
     NFZ=3               !First zero
 
     tsync=2.0
-    jsps=nint((12.6-tsync)*12000.0/ND)
+    jsps=nint((12.8-tsync)*12000.0/ND)
     iloc=minloc(abs(isps-jsps))
     NSPS=isps(iloc(1))  !Samples per symbol
     NS=nint(tsync*12000.0/NSPS)
diff --git a/lib/superfox/sfoxtest.f90 b/lib/superfox/sfoxtest.f90
index 0d9e33247..b624792c0 100644
--- a/lib/superfox/sfoxtest.f90
+++ b/lib/superfox/sfoxtest.f90
@@ -96,13 +96,9 @@ program sfoxtest
 
 ! Generate a message
   msg0=0
-  do i=1,KK-2
-!     msg0(i)=i-1
+  do i=1,KK
      msg0(i)=int(NQ*ran1(idummy))
-!     msg0(i)=0
-!     if(i.gt.ND1) msg0(i)=NQ-1
   enddo
-! Append a CRC here ...
 
   call rs_init_sf(MM,NQ,NN,KK,NFZ)          !Initialize the Karn codec
   call rs_encode_sf(msg0,parsym)            !Compute parity symbols
@@ -115,7 +111,7 @@ program sfoxtest
 ! Generate cdat, the SuperFox waveform
   call sfox_gen(chansym0,f0,fsample,syncwidth,cdat)
 
-  do isnr=0,-25,-1
+  do isnr=-8,-20,-1
      snr=isnr
      if(snrdb.ne.0.0) snr=snrdb
      sig=sqrt(2*bandwidth_ratio)*10.0**(0.05*snr)
@@ -142,7 +138,7 @@ program sfoxtest
         f1=f0
         if(f0.eq.0.0) then
            f1=1500.0 + 200.0*(ran1(idummy)-0.5)
-           xdt=2.0*(ran1(idummy)-0.5)
+           xdt=0.6*(ran1(idummy)-0.5)
            call sfox_gen(chansym0,f1,fsample,syncwidth,cdat,clo)
         endif