mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-05 00:41:19 -05:00
9590ff5f43
but not used". git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/trunk@275 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
106 lines
3.3 KiB
Fortran
106 lines
3.3 KiB
Fortran
subroutine stdecode(s2,nchan,nz,sigma,dtbuf,df,stlim0,
|
|
+ DFTolerance,cfile6,pick,istart)
|
|
|
|
C Search for and decode single-tone messages.
|
|
|
|
real s2(nchan,nz)
|
|
integer DFTolerance
|
|
logical pick
|
|
character cfile6*6,msg3*3
|
|
character*90 line
|
|
common/ccom/nline,tping(100),line(100)
|
|
|
|
NSPD=25 !Change if FSK110 is implemented
|
|
LTone=2
|
|
NBaud=11025/NSPD
|
|
|
|
stlim=stlim0
|
|
if(pick) stlim=stlim0-1.0
|
|
iwidth=1
|
|
ts0=-1.0
|
|
dt=1.0/11025.0
|
|
|
|
C In each time slice, find largest peak between LTone*NBaud-DFTolerance and
|
|
C (LTone+3)*NBaud+DFTolerance.
|
|
|
|
ia=(LTone*NBaud-DFTolerance)/df - 5.0
|
|
ib=((LTone+3)*NBaud+DFTolerance)/df - 4.0
|
|
do j=1,nz
|
|
smax=0.
|
|
do i=ia,ib !Get the spectral peak
|
|
if(s2(i,j).gt.smax) then
|
|
smax=s2(i,j)
|
|
ipk=i
|
|
endif
|
|
enddo
|
|
peak=dB(smax/sigma) - 14.0 !Empirical
|
|
C constant should be dB(43/2500) = -17.6 dB?
|
|
|
|
if(peak.gt.stlim) then
|
|
C To minimize false ST decodings from QRN and MT pings, find the
|
|
C second best peak (excluding points around the first peak).
|
|
smax2=0.
|
|
do i=ia,ib
|
|
if((abs(i-ipk).gt.iwidth) .and. s2(i,j).gt.smax2) then
|
|
smax2=s2(i,j)
|
|
endif
|
|
enddo
|
|
|
|
C Larger values of ratlim make it more likely to report ST decodings.
|
|
ratlim=0.18
|
|
if(stlim.lt.-2.5) ratlim=0.20
|
|
if(stlim.lt.-3.5) ratlim=0.22
|
|
if(stlim.lt.-4.5) ratlim=0.24
|
|
if(pick) ratlim=0.27 !Fine tuning here...
|
|
if(smax2/smax.gt.ratlim) goto 20
|
|
|
|
call peakup(s2(ipk-1,j),s2(ipk,j),s2(ipk+1,j),dx)
|
|
freq=(ipk+5+dx)*df
|
|
tstart=j*dtbuf + dt*(istart-1)
|
|
mswidth=20
|
|
nwidth=0
|
|
nstrength=0
|
|
n=nint(freq/NBaud)
|
|
noffset=freq-n*NBaud
|
|
if((noffset.lt.-DFTolerance) .or.
|
|
+ (noffset.gt.DFTolerance)) goto 20
|
|
|
|
C The numbers 2 and 5 depend on Ltone:
|
|
if(n.lt.2 .or. n.gt.5) goto 20
|
|
|
|
C OK, this detection has survived all tests. Save it for output
|
|
C (uness perhaps it is redundant).
|
|
|
|
if(n.eq.LTone) msg3='R26'
|
|
if(n.eq.LTone+1) msg3='R27'
|
|
if(n.eq.LTone+2) msg3='RRR'
|
|
if(n.eq.LTone+3) msg3='73'
|
|
|
|
C Now check for redundant detections. (Not sure, now, why I chose
|
|
C the time span 0.11 s.)
|
|
if(tstart-ts0.gt.0.11) then
|
|
peak0=0. !If time diff>0.11s, start fresh
|
|
else
|
|
if(peak.le.peak0) goto 20
|
|
nline=nline-1 !Delete previous, this one's better
|
|
peak0=peak !Save best peak
|
|
endif
|
|
|
|
C OK, we want to output this one. Save the information.
|
|
if(nline.le.99) nline=nline+1
|
|
ts0=tstart
|
|
tping(nline)=tstart
|
|
nst=(int(smax/smax2)-4)/2 + 1
|
|
if(nst.lt.1) nst=1
|
|
if(nst.gt.3) nst=3
|
|
write(line(nline),1050) cfile6,tstart,mswidth,int(peak),
|
|
+ nwidth,nstrength,noffset,msg3,nst
|
|
1050 format(a6,f5.1,i5,i3,1x,2i1,i5,1x,a3,40x,i3)
|
|
endif
|
|
|
|
20 continue
|
|
enddo
|
|
|
|
return
|
|
end
|