WSJT-X/lib/hspec.f90
2018-07-27 09:45:14 -04:00

108 lines
2.8 KiB
Fortran

subroutine hspec(id2,k,nutc0,ntrpdepth,nrxfreq,ntol,ncontest,bmsk144, &
btrain,pcoeffs,ingain,mycall,hiscall,bshmsg,bswl,datadir,green,s, &
jh,pxmax,dbNoGain,line1,mygrid)
! Input:
! k pointer to the most recent new data
! nutc0 UTC for display of decode(s)
! ntrpdepth TR period and 1000*ndepth
! nrxfreq Rx audio center frequency
! ntol Decoding range is +/- ntol
! ncontest Contest type (0=NONE 1=NA_VHF 2=EU_VHF 3=FIELD_DAY 4=RTTY)
! bmsk144 Boolean, true if in MSK144 mode
! btrain Boolean, turns on training in MSK144 mode
! ingain Relative gain for spectra
! Output:
! green() power
! s() spectrum for horizontal spectrogram
! jh index of most recent data in green(), s()
parameter (JZ=703)
character*80 line1
character*512 datadir
character*12 mycall,hiscall
character*6 mygrid
integer*2 id2(0:120*12000-1)
logical*1 bmsk144,bshmsg,btrain,bswl
real green(0:JZ-1)
real s(0:63,0:JZ-1)
real x(512)
real*8 pcoeffs(5)
complex cx(0:256)
data rms/999.0/,k0/99999999/
equivalence (x,cx)
save ja,rms0
ndepth=ntrpdepth/1000
ntrperiod=ntrpdepth - 1000*ndepth
gain=10.0**(0.1*ingain)
nfft=512
nstep=nfft
nblks=7
if(ntrperiod.lt.30) then
nstep=256
nblks=14
endif
if(k.gt.30*12000) go to 900
if(k.lt.nfft) then
jh=0
go to 900 !Wait for enough samples to start
endif
if(k.lt.k0) then !Start a new data block
ja=-nstep
jh=-1
rms0=0.0
endif
pxmax = 0;
do iblk=1,nblks
if(jh.lt.JZ-1) jh=jh+1
ja=ja+nstep
jb=ja+nfft-1
x=id2(ja:jb)
sq=dot_product(x,x)
xmax = maxval(x);
xmin = abs(minval(x));
if (xmin > xmax) xmax = xmin;
if (xmax.gt.0.0) pxmax=20.0*log10(xmax);
rms=sqrt(gain*sq/nfft)
rms2=sqrt(sq/nfft);
green(jh)=0.
if(rms.gt.0.0) then
green(jh)=20.0*log10(rms)
dbNoGain=20.0*log10(rms2);
endif
call four2a(x,nfft,1,-1,0) !Real-to-complex FFT
df=12000.0/nfft
fac=(1.0/nfft)**2
do i=1,64
j=2*i
sx=real(cx(j))**2 + aimag(cx(j))**2 + real(cx(j-1))**2 + &
aimag(cx(j-1))**2
s(i-1,jh)=fac*gain*sx
enddo
if(ja+2*nfft.gt.k) exit
enddo
k0=k
if(bmsk144) then
if(k.ge.7168) then
tsec=(k-7168)/12000.0
k0=k-7168
tt1=sum(float(abs(id2(k0:k0+3583))))
k0=k-3584
tt2=sum(float(abs(id2(k0:k0+3583))))
if(tt1.ne.0.0 .and. tt2.ne.0) then
call mskrtd(id2(k-7168+1:k),nutc0,tsec,ntol,nrxfreq,ndepth, &
mycall,mygrid,hiscall,bshmsg,btrain,pcoeffs,bswl, &
datadir,line1)
endif
endif
endif
900 return
end subroutine hspec