mirror of https://github.com/saitohirga/WSJT-X.git
53 lines
1.0 KiB
Fortran
53 lines
1.0 KiB
Fortran
subroutine filt8(f0,nslots,width,wave)
|
|
|
|
parameter (NFFT=180000,NH=NFFT/2)
|
|
real wave(NFFT)
|
|
real x(NFFT)
|
|
real s1(0:NH)
|
|
real s2(0:NH)
|
|
complex cx(0:NH)
|
|
equivalence (x,cx)
|
|
|
|
x=wave
|
|
call four2a(cx,NFFT,1,-1,0) !r2c
|
|
df=12000.0/NFFT
|
|
fa=f0 - 0.5*6.25
|
|
fb=f0 + 7.5*6.25 + (nslots-1)*60.0
|
|
ia2=nint(fa/df)
|
|
ib1=nint(fb/df)
|
|
ia1=nint(ia2-width/df)
|
|
ib2=nint(ib1+width/df)
|
|
pi=4.0*atan(1.0)
|
|
do i=ia1,ia2
|
|
fil=(1.0 + cos(pi*df*(i-ia2)/width))/2.0
|
|
cx(i)=fil*cx(i)
|
|
enddo
|
|
do i=ib1,ib2
|
|
fil=(1.0 + cos(pi*df*(i-ib1)/width))/2.0
|
|
cx(i)=fil*cx(i)
|
|
enddo
|
|
cx(0:ia1-1)=0.
|
|
cx(ib2+1:)=0.
|
|
|
|
call four2a(cx,nfft,1,1,-1) !c2r
|
|
wave=x/nfft
|
|
|
|
!###
|
|
if(nslots.ne.99) return
|
|
x=wave
|
|
call four2a(cx,NFFT,1,-1,0) !r2c
|
|
do i=0,NH
|
|
s1(i)=real(cx(i))**2 + aimag(cx(i))**2
|
|
enddo
|
|
nadd=20
|
|
call smo(s1,NH+1,s2,nadd)
|
|
do i=0,NH
|
|
freq=i*df
|
|
write(29,3101) freq,db(s2(i)) - 72.0
|
|
3101 format(2f12.3)
|
|
enddo
|
|
!###
|
|
|
|
return
|
|
end subroutine filt8
|