mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-19 10:32:02 -05:00
111 lines
3.0 KiB
FortranFixed
111 lines
3.0 KiB
FortranFixed
|
subroutine avemsg6m(s2db,nz,nslim,NFixLen,cfile6,lcum,
|
||
|
|
+ f0,lumsg,npkept)
|
||
|
|
|
||
|
|
C Attempts to find message length and then decodes an average message.
|
||
|
|
|
||
|
|
real s2db(0:43,nz)
|
||
|
|
real s2dc(0:43,22)
|
||
|
|
real wgt(22)
|
||
|
|
real acf(0:430)
|
||
|
|
logical lcum
|
||
|
|
character*43 pua
|
||
|
|
character*6 cfile6
|
||
|
|
character*22 avemsg,blanks
|
||
|
|
data pua/'0123456789., /#?$ABCDEFGHIJKLMNOPQRSTUVWXYZ'/
|
||
|
|
data blanks/' '/
|
||
|
|
data twopi/6.283185307/
|
||
|
|
data offset/20.6/
|
||
|
|
|
||
|
|
C Adjustable sig limit, depending on length of data to average.
|
||
|
|
nslim2=nslim - 9 + 4.0*log10(624.0/nz) !### +10 was here
|
||
|
|
|
||
|
|
k=0
|
||
|
|
sum=0.
|
||
|
|
nsum=0
|
||
|
|
do j=1,nz
|
||
|
|
if(mod(j,3).eq.1) then
|
||
|
|
sum=sum+s2db(0,j) !Measure avg sig strength for sync tone
|
||
|
|
nsum=nsum+1
|
||
|
|
else
|
||
|
|
k=k+1
|
||
|
|
call move(s2db(0,j),s2db(0,k),44) !Save data spectra
|
||
|
|
endif
|
||
|
|
enddo
|
||
|
|
sig=sum/nsum !Signal strength estimate
|
||
|
|
nsig=nint(db(sig)-offset)
|
||
|
|
|
||
|
|
C Most of the time in this routine is in this loop.
|
||
|
|
kz=k
|
||
|
|
do lag=0,kz-1
|
||
|
|
sum=0.
|
||
|
|
do j=1,kz-lag
|
||
|
|
do i=0,43
|
||
|
|
sum=sum+s2db(i,j)*s2db(i,j+lag)
|
||
|
|
enddo
|
||
|
|
enddo
|
||
|
|
acf(lag)=sum
|
||
|
|
enddo
|
||
|
|
acf0=acf(0)
|
||
|
|
do lag=0,kz-1
|
||
|
|
acf(lag)=acf(lag)/acf0
|
||
|
|
enddo
|
||
|
|
|
||
|
|
lmsg1=NFixLen/256
|
||
|
|
lmsg2=NFixLen-256*lmsg1
|
||
|
|
if(mod(lmsg1,2).eq.1) lmsg1=lmsg1+1
|
||
|
|
if(mod(lmsg2,2).eq.1) lmsg2=lmsg2+1
|
||
|
|
smax=-1.e9
|
||
|
|
do ip=4,22,2 !Compute periodogram for allowed msg periods
|
||
|
|
if(NFixLen.ne.0 .and. ip.ne.4 .and. ip.ne.lmsg1
|
||
|
|
+ .and. ip.ne.lmsg2) go to 5
|
||
|
|
f=1.0/ip
|
||
|
|
s=0.
|
||
|
|
do lag=0,kz-1
|
||
|
|
s=s+acf(lag)*cos(twopi*f*lag)
|
||
|
|
enddo
|
||
|
|
if(s.gt.smax) then
|
||
|
|
smax=s
|
||
|
|
msglen=ip !Save best message length
|
||
|
|
endif
|
||
|
|
5 enddo
|
||
|
|
|
||
|
|
C Average the symbols from s2db into s2dc.
|
||
|
|
|
||
|
|
call zero(s2dc,44*22)
|
||
|
|
call zero(wgt,22)
|
||
|
|
do j=1,kz
|
||
|
|
k=mod(j-1,msglen)+1
|
||
|
|
call add(s2db(0,j),s2dc(0,k),s2dc(0,k),44)
|
||
|
|
wgt(k)=wgt(k)+1.0
|
||
|
|
enddo
|
||
|
|
|
||
|
|
do j=1,msglen !Hard-decode the avg msg,
|
||
|
|
smax=-1.e9 !picking max bin for each char
|
||
|
|
do i=1,43
|
||
|
|
s2dc(i,j)=s2dc(i,j)/wgt(j)
|
||
|
|
if(s2dc(i,j).gt.smax) then
|
||
|
|
smax=s2dc(i,j)
|
||
|
|
ipk=i
|
||
|
|
endif
|
||
|
|
enddo
|
||
|
|
k=mod(ipk,3)
|
||
|
|
i=ipk
|
||
|
|
avemsg(j:j)=pua(i:i)
|
||
|
|
enddo
|
||
|
|
ndf0=nint(f0-1076.66)
|
||
|
|
do i=1,msglen
|
||
|
|
if(avemsg(i:i).eq.' ') goto 10
|
||
|
|
enddo
|
||
|
|
go to 20
|
||
|
|
10 avemsg=avemsg(i+1:msglen)//avemsg(1:i)
|
||
|
|
20 if(nsig.gt.nslim2) then
|
||
|
|
npkept=npkept+1
|
||
|
|
avemsg=avemsg(1:msglen)//blanks
|
||
|
|
write(lumsg,1020) cfile6,nsig,ndf0,avemsg,msglen
|
||
|
|
if(lcum) write(21,1020) cfile6,nsig,ndf0,avemsg,msglen
|
||
|
|
1020 format(a6,8x,i6,i5,7x,a22,19x,'*',i4)
|
||
|
|
endif
|
||
|
|
|
||
|
|
return
|
||
|
|
end
|