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Cleanup

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This commit is contained in:
Steven Franke 2020-04-21 15:02:57 -05:00
parent 01d555c898
commit 8da98fee1e
1 changed files with 112 additions and 112 deletions
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68
lib/fsk4hf/decode174_74.f90
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@ -2,43 +2,43 @@ subroutine decode174_74(llr,Keff,ndeep,apmask,maxsuper,message74,cw,nharderror,i
! !
! A hybrid bp/osd decoder for the (174,74) code. ! A hybrid bp/osd decoder for the (174,74) code.
! !
integer, parameter:: N=174, K=74, M=N-K integer, parameter:: N=174, K=74, M=N-K
integer*1 cw(N),apmask(N) integer*1 cw(N),apmask(N)
integer*1 decoded(K) integer*1 decoded(K)
integer*1 message74(74) integer*1 message74(74)
integer nrw(M),ncw integer nrw(M),ncw
integer Nm(6,M) integer Nm(6,M)
integer Mn(3,N) ! 3 checks per bit integer Mn(3,N) ! 3 checks per bit
integer synd(M) integer synd(M)
real tov(3,N) real tov(3,N)
real toc(6,M) real toc(6,M)
real tanhtoc(6,M) real tanhtoc(6,M)
real zn(N),zsum(N) real zn(N),zsum(N)
real llr(N) real llr(N)
real Tmn real Tmn
include "ldpc_174_74_parity.f90" include "ldpc_174_74_parity.f90"
decoded=0 decoded=0
toc=0 toc=0
tov=0 tov=0
tanhtoc=0 tanhtoc=0
! initialize messages to checks ! initialize messages to checks
do j=1,M do j=1,M
do i=1,nrw(j) do i=1,nrw(j)
toc(i,j)=llr((Nm(i,j))) toc(i,j)=llr((Nm(i,j)))
enddo enddo
enddo enddo
ncnt=0 ncnt=0
nclast=0 nclast=0
maxiterations=1 maxiterations=1
zsum=0.0 zsum=0.0
do isuper=1,maxsuper do isuper=1,maxsuper
do iter=0,maxiterations do iter=0,maxiterations
! Update bit log likelihood ratios (tov=0 in iteration 0). ! Update bit log likelihood ratios (tov=0 in iteration 0).
do i=1,N do i=1,N
if( apmask(i) .ne. 1 ) then if( apmask(i) .ne. 1 ) then
@ -47,7 +47,7 @@ do iter=0,maxiterations
zn(i)=llr(i) zn(i)=llr(i)
endif endif
enddo enddo
zsum=zsum+zn zsum=zsum+zn
! Check to see if we have a codeword (check before we do any iteration). ! Check to see if we have a codeword (check before we do any iteration).
cw=0 cw=0
where( zn .gt. 0. ) cw=1 where( zn .gt. 0. ) cw=1
@ -64,7 +64,7 @@ zsum=zsum+zn
nharderror=count( (2*cw-1)*llr .lt. 0.0 ) nharderror=count( (2*cw-1)*llr .lt. 0.0 )
if(nbadcrc.eq.0) then if(nbadcrc.eq.0) then
message74=decoded(1:74) message74=decoded(1:74)
dmin=0.0 dmin=0.0
return return
endif endif
endif endif
@ -114,15 +114,15 @@ dmin=0.0
enddo enddo
enddo enddo
enddo ! bp iterations enddo ! bp iterations
llr=zsum llr=zsum
call osd174_74(llr,Keff,apmask,ndeep,message74,cw,nharderror,dmin) call osd174_74(llr,Keff,apmask,ndeep,message74,cw,nharderror,dmin)
if(nharderror.gt.0) then if(nharderror.gt.0) then
return return
endif endif
enddo ! super iterations enddo ! super iterations
nharderror=-1 nharderror=-1
return return
end subroutine decode174_74 end subroutine decode174_74