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Improve Es/tropo decoding of MSK144 short messages.

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git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7026 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Steven Franke 2016-08-12 21:41:51 +00:00
parent cc178ab6fa
commit 573615c565
1 changed files with 25 additions and 3 deletions
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28
lib/detectmsk40.f90
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@ -7,7 +7,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
character*6 mycall,hiscall,mycall0,hiscall0
character*22 hashmsg,msgreceived
character*80 lines(100)
character*512 pchk_file,gen_file
character*512 pchk_file
character*512 pchk_file40,gen_file40
complex cbig(n)
complex cdat(NPTS) !Analytic signal
@ -32,6 +32,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
logical ismask(NFFT)
real cbi(42),cbq(42)
real detmet(-2:MAXSTEPS+3)
real detmet2(-2:MAXSTEPS+3)
real detfer(MAXSTEPS)
real rcw(12)
real ddr(NPTS)
@ -117,7 +118,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
nstepsize=60 ! 5ms steps
nstep=(n-NPTS)/nstepsize
detmet=0
detmax=-999.99
detmet2=0
detfer=-999.99
do istp=1,nstep
ns=1+nstepsize*(istp-1)
@ -144,6 +145,8 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
ihpk=iloc(1)
deltah=-real( (ctmp(ihpk-1)-ctmp(ihpk+1)) / (2*ctmp(ihpk)-ctmp(ihpk-1)-ctmp(ihpk+1)) )
ah=tonespec(ihpk)
ahavp=(sum(tonespec,ismask)-ah)/count(ismask)
trath=ah/(ahavp+0.01)
illo=(2000-2*ntol)/df+1
ilhi=(2000+2*ntol)/df+1
ismask=.false.
@ -152,6 +155,8 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
ilpk=iloc(1)
deltal=-real( (ctmp(ilpk-1)-ctmp(ilpk+1)) / (2*ctmp(ilpk)-ctmp(ilpk-1)-ctmp(ilpk+1)) )
al=tonespec(ilpk)
alavp=(sum(tonespec,ismask)-al)/count(ismask)
tratl=al/(alavp+0.01)
fdiff=(ihpk+deltah-ilpk-deltal)*df
i2000=nint(2000/df)+1
i4000=nint(4000/df)+1
@ -163,6 +168,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
ferr=ferrl
endif
detmet(istp)=max(ah,al)
detmet2(istp)=max(trath,tratl)
detfer(istp)=ferr
! write(*,*) istp,ilpk,ihpk,ah,al
enddo ! end of detection-metric and frequency error estimation loop
@ -173,7 +179,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
ndet=0
!do i=1,nstep
!write(77,*) i,detmet(i),detfer(i)
!write(77,*) i,detmet(i),detmet2(i),detfer(i)
!enddo
do ip=1,MAXCAND ! find candidates
@ -190,6 +196,22 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, &
! detmet(il)=0.0
enddo
if( ndet .lt. 3 ) then
do ip=1,MAXCAND-ndet ! Find candidates
iloc=maxloc(detmet2(1:nstep))
il=iloc(1)
if( (detmet2(il) .lt. 20.0) ) exit
if( abs(detfer(il)) .le. ntol ) then
ndet=ndet+1
times(ndet)=((il-1)*nstepsize+NSPM/2)*dt
ferrs(ndet)=detfer(il)
snrs(ndet)=12.0*log10(detmet2(il))/2-9.0
endif
detmet2(max(1,il-1):min(nstep,il+1))=0.0
! detmet2(il)=0.0
enddo
endif
! do ip=1,ndet
! write(*,'(i5,f7.2,f7.2,f7.2)') ip,times(ip),snrs(ip),ferrs(ip)
! enddo