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Use widegraph limits for noise baseline fit. Limit signal search to within the widegraph limits.

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This commit is contained in:
Steven Franke 2020-09-10 14:58:10 -05:00
parent 47fcddcb50
commit 2dcde590df
1 changed files with 6 additions and 17 deletions
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23
lib/fst4_decode.f90
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@ -82,7 +82,6 @@ contains
this%callback => callback
dxcall13=hiscall ! initialize for use in packjt77
mycall13=mycall
fMHz=1.0
if(iwspr.ne.0.and.iwspr.ne.1) return
@ -241,7 +240,7 @@ contains
if(ntrperiod.eq.15) minsync=1.15
! Get first approximation of candidate frequencies
call get_candidates_fst4(c_bigfft,nfft1,nsps,hmod,fs,fa,fb, &
call get_candidates_fst4(c_bigfft,nfft1,nsps,hmod,fs,fa,fb,nfa,nfb, &
minsync,ncand,candidates)
ndecodes=0
@ -626,7 +625,7 @@ contains
end subroutine fst4_downsample
subroutine get_candidates_fst4(c_bigfft,nfft1,nsps,hmod,fs,fa,fb, &
subroutine get_candidates_fst4(c_bigfft,nfft1,nsps,hmod,fs,fa,fb,nfa,nfb, &
minsync,ncand,candidates)
complex c_bigfft(0:nfft1/2) !Full length FFT of raw data
@ -648,20 +647,10 @@ contains
ndh=nd/2
ia=nint(max(100.0,fa)/df2) !Low frequency search limit
ib=nint(min(4800.0,fb)/df2) !High frequency limit
signal_bw=4*(12000.0/nsps)*hmod
analysis_bw=min(4800.0,fb)-max(100.0,fa)
xnoise_bw=10.0*signal_bw !Is this a good compromise?
if(xnoise_bw .lt. 400.0) xnoise_bw=400.0
if(analysis_bw.gt.xnoise_bw) then !Estimate noise baseline over analysis bw
ina=0.9*ia
inb=min(int(1.1*ib),nfft1/2)
else !Estimate noise baseline over noise bw
fcenter=(fa+fb)/2.0
fl = max(100.0,fcenter-xnoise_bw/2.)/df2
fh = min(4800.0,fcenter+xnoise_bw/2.)/df2
ina=nint(fl)
inb=nint(fh)
endif
ina=nint(max(100.0,real(nfa))/df2) !Low freq limit for noise baseline fit
inb=nint(min(4800.0,real(nfb))/df2) !High freq limit for noise fit
if(ia.lt.ina) ia=ina
if(ib.gt.inb) ib=inb
nnw=nint(48000.*nsps*2./fs)
allocate (s(nnw))
s=0. !Compute low-resolution power spectrum