Much better algorithm for detecting and removing birdies in Q65.

This commit is contained in:
Joe Taylor 2021-02-12 13:26:22 -05:00
parent 9f6cf3444e
commit 10e08b0e94
2 changed files with 26 additions and 16 deletions

View File

@ -58,10 +58,8 @@ subroutine q65_dec0(iavg,nutc,iwave,ntrperiod,nfqso,ntol,ndepth,lclearave, &
parameter (LN=2176*63) !LN=LL*NN; LL=64*(mode_q65+2), NN=63
integer*2 iwave(0:12000*ntrperiod-1) !Raw data
integer dat4(13)
integer ipk1(1)
character*37 decoded
logical first,lclearave
integer, allocatable :: hist(:)
real, allocatable :: s1(:,:) !Symbol spectra, 1/8-symbol steps
real, allocatable :: s3(:,:) !Data-symbol energies s3(LL,63)
real, allocatable :: ccf1(:) !CCF(freq) at fixed lag (red)
@ -101,7 +99,6 @@ subroutine q65_dec0(iavg,nutc,iwave,ntrperiod,nfqso,ntol,ndepth,lclearave, &
allocate(s3(-64:LL-65,63))
allocate(ccf1(-ia2:ia2))
allocate(ccf2(iz))
allocate(hist(LL))
if(LL.ne.LL0 .or. iz.ne.iz0 .or. jz.ne.jz0 .or. lclearave) then
if(allocated(s1a)) deallocate(s1a)
allocate(s1a(iz,jz,0:1))
@ -134,18 +131,6 @@ subroutine q65_dec0(iavg,nutc,iwave,ntrperiod,nfqso,ntol,ndepth,lclearave, &
call pctile(s1(i0-64:i0-65+LL,1:jz),LL*jz,45,base)
s1=s1/base
! Detect and remove strong non-drifting birdies
hist=0
do j=1,jz
ipk1=maxloc(s1(i0-64:i0+LL-65,j))
i=ipk1(1)
hist(i)=hist(i)+1
enddo
nbirdie=80
do i=1,LL
if(hist(i).gt.nbirdie) s1(i0-65+i,1:jz)=1.0
enddo
! Apply fast AGC to the symbol spectra
s1max=20.0 !Empirical choice
do j=1,jz !### Maybe wrong way? ###
@ -559,6 +544,7 @@ subroutine q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
if(j.ge.1 .and. j.le.jz) s3(-64:LL-65,n)=s1(i1:i2,j)
enddo
endif
call q65_bzap(s3,LL) !Zap birdies
return
end subroutine q65_s1_to_s3
@ -611,4 +597,27 @@ subroutine q65_sync_curve(ccf1,ia,ib,rms1)
return
end subroutine q65_sync_curve
subroutine q65_bzap(s3,LL)
parameter (NBZAP=15)
real s3(-64:LL-65,63)
integer ipk1(1)
integer, allocatable :: hist(:)
allocate(hist(-64:LL-65))
hist=0
do j=1,63
ipk1=maxloc(s3(:,j))
i=ipk1(1) - 65
hist(i)=hist(i)+1
enddo
if(maxval(hist).gt.NBZAP) then
do i=-64,LL-65
if(hist(i).gt.NBZAP) s3(i,1:63)=1.0
enddo
endif
return
end subroutine q65_bzap
end module q65

View File

@ -56,6 +56,7 @@ subroutine q65_loops(c00,npts2,nsps2,nsubmode,ndepth,jpk0, &
call pctile(s3,LL*NN,40,base)
s3=s3/base
where(s3(1:LL*NN)>s3lim) s3(1:LL*NN)=s3lim
call q65_bzap(s3,LL) !Zap birdies
do ibw=ibwa,ibwb
ndist=ndf**2 + ndt**2 + (ibw-ibw0)**2
if(ndist.gt.maxdist) cycle