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Merge branch 'feat-ft2' of bitbucket.org:k1jt/wsjtx into feat-ft2

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This commit is contained in:
Steve Franke
2019-02-25 15:03:55 -06:00
parent 3759198982 fdfb655b06
commit fdca7c2dcb
5 changed files with 79 additions and 30 deletions
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lib/symspec.f90
+16 -20
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@@ -1,13 +1,14 @@
subroutine symspec(shared_data,k,ntrperiod,nsps,ingain,nminw,pxdb,s, &
df3,ihsym,npts8,pxdbmax)
subroutine symspec(shared_data,k,ntrperiod,nsps,ingain,bLowSidelobes, &
nminw,pxdb,s,df3,ihsym,npts8,pxdbmax)
! Input:
! k pointer to the most recent new data
! ntrperiod T/R sequence length, minutes
! nsps samples per symbol, at 12000 Hz
! ndiskdat 0/1 to indicate if data from disk
! nb 0/1 status of noise blanker (off/on)
! nbslider NB setting, 0-100
! k pointer to the most recent new data
! ntrperiod T/R sequence length, minutes
! nsps samples per symbol, at 12000 Hz
! bLowSidelobes true to use windowed FFTs
! ndiskdat 0/1 to indicate if data from disk
! nb 0/1 status of noise blanker (off/on)
! nbslider NB setting, 0-100
! Output:
! pxdb raw power (0-90 dB)
@@ -29,6 +30,7 @@ subroutine symspec(shared_data,k,ntrperiod,nsps,ingain,nminw,pxdb,s, &
real*4 tmp(NSMAX)
complex cx(0:MAXFFT3/2)
integer nch(7)
logical*1 bLowSidelobes
common/spectra/syellow(NSMAX),ref(0:3456),filter(0:3456)
data k0/99999999/,nfft3z/0/
@@ -48,23 +50,17 @@ subroutine symspec(shared_data,k,ntrperiod,nsps,ingain,nminw,pxdb,s, &
if(nfft3.ne.nfft3z) then
! Compute new window
pi=4.0*atan(1.0)
! width=0.25*nsps
! do i=1,nfft3
! z=(i-nfft3/2)/width
! w3(i)=exp(-z*z)
! enddo
! Coefficients taken from equation 37 of NUSC report:
! "Some windows with very good sidelobe behavior: application to
! discrete Hilbert Transform, by Albert Nuttall"
!
a0=0.3635819
a1=-0.4891775;
a2=0.1365995;
a3=-0.0106411;
do i=1,nfft3
w3(i)=a0+a1*cos(2*pi*(i-1)/(nfft3))+ &
a2*cos(4*pi*(i-1)/(nfft3))+ &
a3*cos(6*pi*(i-1)/(nfft3))
w3(i)=a0+a1*cos(2*pi*(i-1)/(nfft3))+ &
a2*cos(4*pi*(i-1)/(nfft3))+ &
a3*cos(6*pi*(i-1)/(nfft3))
enddo
nfft3z=nfft3
endif
@@ -99,10 +95,10 @@ subroutine symspec(shared_data,k,ntrperiod,nsps,ingain,nminw,pxdb,s, &
enddo
ihsym=ihsym+1
xc(0:nfft3-1)=w3(1:nfft3)*xc(0:nfft3-1) !Apply window w3
call four2a(xc,nfft3,1,-1,0) !Real-to-complex FFT
if(bLowSidelobes) xc(0:nfft3-1)=w3(1:nfft3)*xc(0:nfft3-1) !Apply window
call four2a(xc,nfft3,1,-1,0) !Real-to-complex FFT
df3=12000.0/nfft3 !JT9-1: 0.732 Hz = 0.42 * tone spacing
df3=12000.0/nfft3 !JT9: 0.732 Hz = 0.42 * tone spacing
iz=min(NSMAX,nint(5000.0/df3))
fac=(1.0/nfft3)**2
do i=1,iz