2020-06-27 09:53:11 -04:00
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module fst240_decode
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2020-06-30 16:06:18 -04:00
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type :: fst240_decoder
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procedure(fst240_decode_callback), pointer :: callback
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2020-06-27 09:53:11 -04:00
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contains
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2020-06-30 16:06:18 -04:00
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procedure :: decode
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end type fst240_decoder
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abstract interface
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subroutine fst240_decode_callback (this,nutc,sync,nsnr,dt,freq, &
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decoded,nap,qual,ntrperiod,lwspr)
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import fst240_decoder
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implicit none
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class(fst240_decoder), intent(inout) :: this
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integer, intent(in) :: nutc
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real, intent(in) :: sync
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integer, intent(in) :: nsnr
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real, intent(in) :: dt
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real, intent(in) :: freq
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character(len=37), intent(in) :: decoded
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integer, intent(in) :: nap
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real, intent(in) :: qual
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integer, intent(in) :: ntrperiod
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logical, intent(in) :: lwspr
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end subroutine fst240_decode_callback
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end interface
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2020-06-27 09:53:11 -04:00
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contains
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2020-06-30 16:06:18 -04:00
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subroutine decode(this,callback,iwave,nutc,nQSOProgress,nfqso, &
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2020-07-02 13:30:18 -04:00
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nfa,nfb,nsubmode,ndepth,ntrperiod,nexp_decode,ntol,nzhsym, &
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2020-06-30 15:11:36 -04:00
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emedelay,lapcqonly,napwid,mycall,hiscall,nfsplit,iwspr)
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2020-06-27 09:53:11 -04:00
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2020-06-30 16:06:18 -04:00
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use timer_module, only: timer
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use packjt77
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2020-07-07 21:25:25 -04:00
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use, intrinsic :: iso_c_binding
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2020-06-30 16:06:18 -04:00
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include 'fst240/fst240_params.f90'
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parameter (MAXCAND=100)
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class(fst240_decoder), intent(inout) :: this
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procedure(fst240_decode_callback) :: callback
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character*37 decodes(100)
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character*37 msg,msgsent
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character*77 c77
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character*12 mycall,hiscall
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character*12 mycall0,hiscall0
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complex, allocatable :: c2(:)
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complex, allocatable :: cframe(:)
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complex, allocatable :: c_bigfft(:) !Complex waveform
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2020-07-07 21:25:25 -04:00
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real, allocatable, target :: r_data(:)
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complex, pointer, dimension(:) :: c_data_ptr
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2020-06-30 16:06:18 -04:00
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real llr(240),llra(240),llrb(240),llrc(240),llrd(240)
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real candidates(100,4)
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real bitmetrics(320,4)
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real s4(0:3,NN)
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real minsync
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logical lapcqonly
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integer itone(NN)
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integer hmod
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integer*1 apmask(240),cw(240)
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integer*1 hbits(320)
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integer*1 message101(101),message74(74),message77(77)
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integer*1 rvec(77)
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integer apbits(240)
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integer nappasses(0:5) ! # of decoding passes for QSO states 0-5
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integer naptypes(0:5,4) ! (nQSOProgress,decoding pass)
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integer mcq(29),mrrr(19),m73(19),mrr73(19)
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logical badsync,unpk77_success,single_decode
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logical first,nohiscall,lwspr
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integer*2 iwave(300*12000)
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data mcq/0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0/
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data mrrr/0,1,1,1,1,1,1,0,1,0,0,1,0,0,1,0,0,0,1/
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data m73/0,1,1,1,1,1,1,0,1,0,0,1,0,1,0,0,0,0,1/
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data mrr73/0,1,1,1,1,1,1,0,0,1,1,1,0,1,0,1,0,0,1/
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data rvec/0,1,0,0,1,0,1,0,0,1,0,1,1,1,1,0,1,0,0,0,1,0,0,1,1,0,1,1,0, &
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1,0,0,1,0,1,1,0,0,0,0,1,0,0,0,1,0,1,0,0,1,1,1,1,0,0,1,0,1, &
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0,1,0,1,0,1,1,0,1,1,1,1,1,0,0,0,1,0,1/
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data first/.true./
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save first,apbits,nappasses,naptypes,mycall0,hiscall0
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this%callback => callback
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dxcall13=hiscall ! initialize for use in packjt77
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mycall13=mycall
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2020-07-04 13:57:51 -04:00
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fMHz=1.0
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2020-07-04 10:15:57 -04:00
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2020-06-30 16:06:18 -04:00
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if(first) then
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mcq=2*mod(mcq+rvec(1:29),2)-1
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mrrr=2*mod(mrrr+rvec(59:77),2)-1
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m73=2*mod(m73+rvec(59:77),2)-1
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mrr73=2*mod(mrr73+rvec(59:77),2)-1
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nappasses(0)=2
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nappasses(1)=2
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nappasses(2)=2
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nappasses(3)=2
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nappasses(4)=2
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nappasses(5)=3
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2020-06-30 09:42:54 -04:00
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! iaptype
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!------------------------
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! 1 CQ ??? ??? (29 ap bits)
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! 2 MyCall ??? ??? (29 ap bits)
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! 3 MyCall DxCall ??? (58 ap bits)
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! 4 MyCall DxCall RRR (77 ap bits)
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! 5 MyCall DxCall 73 (77 ap bits)
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! 6 MyCall DxCall RR73 (77 ap bits)
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!********
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2020-06-30 16:06:18 -04:00
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naptypes(0,1:4)=(/1,2,0,0/) ! Tx6 selected (CQ)
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naptypes(1,1:4)=(/2,3,0,0/) ! Tx1
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naptypes(2,1:4)=(/2,3,0,0/) ! Tx2
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naptypes(3,1:4)=(/3,6,0,0/) ! Tx3
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naptypes(4,1:4)=(/3,6,0,0/) ! Tx4
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naptypes(5,1:4)=(/3,1,2,0/) ! Tx5
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mycall0=''
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hiscall0=''
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first=.false.
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endif
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l1=index(mycall,char(0))
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if(l1.ne.0) mycall(l1:)=" "
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l1=index(hiscall,char(0))
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if(l1.ne.0) hiscall(l1:)=" "
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if(mycall.ne.mycall0 .or. hiscall.ne.hiscall0) then
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apbits=0
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apbits(1)=99
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apbits(30)=99
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if(len(trim(mycall)) .lt. 3) go to 10
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nohiscall=.false.
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hiscall0=hiscall
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if(len(trim(hiscall0)).lt.3) then
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hiscall0=mycall ! use mycall for dummy hiscall - mycall won't be hashed.
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nohiscall=.true.
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endif
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msg=trim(mycall)//' '//trim(hiscall0)//' RR73'
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i3=-1
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n3=-1
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call pack77(msg,i3,n3,c77)
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call unpack77(c77,1,msgsent,unpk77_success)
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if(i3.ne.1 .or. (msg.ne.msgsent) .or. .not.unpk77_success) go to 10
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read(c77,'(77i1)') message77
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message77=mod(message77+rvec,2)
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call encode174_91(message77,cw)
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apbits=2*cw-1
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if(nohiscall) apbits(30)=99
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10 continue
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mycall0=mycall
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hiscall0=hiscall
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2020-06-30 09:42:54 -04:00
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endif
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!************************************
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2020-06-30 16:06:18 -04:00
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hmod=2**nsubmode
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if(nfqso+nqsoprogress.eq.-999) return
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2020-06-30 17:23:58 -04:00
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Keff=91
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2020-06-27 09:53:11 -04:00
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nmax=15*12000
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2020-06-30 16:06:18 -04:00
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single_decode=iand(nexp_decode,32).eq.32
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if(ntrperiod.eq.15) then
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nsps=720
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nmax=15*12000
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ndown=18/hmod !nss=40,80,160,400
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if(hmod.eq.4) ndown=4
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if(hmod.eq.8) ndown=2
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nfft1=int(nmax/ndown)*ndown
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else if(ntrperiod.eq.30) then
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nsps=1680
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nmax=30*12000
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ndown=42/hmod !nss=40,80,168,336
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nfft1=359856
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if(hmod.eq.4) then
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ndown=10
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nfft1=nmax
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endif
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if(hmod.eq.8) then
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ndown=5
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nfft1=nmax
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endif
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else if(ntrperiod.eq.60) then
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nsps=3888
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nmax=60*12000
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ndown=96/hmod !nss=36,81,162,324
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if(hmod.eq.1) ndown=108
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nfft1=int(719808/ndown)*ndown
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else if(ntrperiod.eq.120) then
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nsps=8200
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nmax=120*12000
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ndown=200/hmod !nss=40,82,164,328
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if(hmod.eq.1) ndown=205
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nfft1=int(nmax/ndown)*ndown
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else if(ntrperiod.eq.300) then
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nsps=21504
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nmax=300*12000
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ndown=512/hmod !nss=42,84,168,336
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nfft1=int((nmax-200)/ndown)*ndown
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end if
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nss=nsps/ndown
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fs=12000.0 !Sample rate
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fs2=fs/ndown
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nspsec=nint(fs2)
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dt=1.0/fs !Sample interval (s)
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dt2=1.0/fs2
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tt=nsps*dt !Duration of "itone" symbols (s)
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baud=1.0/tt
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sigbw=4.0*hmod*baud
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nfft2=nfft1/ndown !make sure that nfft1 is exactly nfft2*ndown
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nfft1=nfft2*ndown
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nh1=nfft1/2
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allocate( r_data(1:nfft1+2) )
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2020-07-07 21:25:25 -04:00
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call c_f_pointer (c_loc (r_data), c_data_ptr, [(nfft1+2)/2]) ! c_data_ptr shares memory with r_data
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2020-06-30 16:06:18 -04:00
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allocate( c_bigfft(0:nfft1/2) )
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allocate( c2(0:nfft2-1) )
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allocate( cframe(0:160*nss-1) )
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2020-07-02 13:30:18 -04:00
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if(ndepth.eq.3) then
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2020-07-04 10:15:57 -04:00
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nblock=4
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2020-06-30 16:06:18 -04:00
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if(hmod.eq.1) nblock=4 ! number of block sizes to try
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jittermax=2
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norder=3
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2020-07-02 13:30:18 -04:00
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elseif(ndepth.eq.2) then
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2020-06-30 16:06:18 -04:00
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nblock=1
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if(hmod.eq.1) nblock=3
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jittermax=0
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norder=3
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2020-07-02 13:30:18 -04:00
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elseif(ndepth.eq.1) then
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2020-06-30 16:06:18 -04:00
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nblock=1
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jittermax=0
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norder=3
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2020-06-29 13:15:28 -04:00
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endif
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2020-06-30 16:06:18 -04:00
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! The big fft is done once and is used for calculating the smoothed spectrum
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2020-06-27 09:53:11 -04:00
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! and also for downconverting/downsampling each candidate.
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2020-06-30 16:06:18 -04:00
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r_data(1:nfft1)=iwave(1:nfft1)
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r_data(nfft1+1:nfft1+2)=0.0
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2020-07-07 21:25:25 -04:00
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call four2a(c_data_ptr,nfft1,1,-1,0)
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2020-06-30 16:06:18 -04:00
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c_bigfft=cmplx(r_data(1:nfft1+2:2),r_data(2:nfft1+2:2))
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2020-07-02 13:30:18 -04:00
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! write(*,3001) iwspr,nfa,nfb,nfsplit,ndepth
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2020-06-30 20:04:44 -04:00
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!3001 format('a',5i5)
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! iwspr=1 !### For hardwired tests ###
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2020-06-30 16:06:18 -04:00
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if(iwspr.eq.0) then
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itype1=1
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itype2=1
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elseif( iwspr.eq.1 ) then
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itype1=2
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itype2=2
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elseif( iwspr.eq.2 ) then
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itype1=1
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itype2=2
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endif
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2020-07-04 10:15:57 -04:00
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if(hmod.eq.1) then
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if(fMHz.lt.2.0) then
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nsyncoh=8 ! Use N=8 for sync
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nhicoh=1 ! Use N=1,2,4,8 for symbol estimation
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else
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nsyncoh=4 ! Use N=4 for sync
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nhicoh=0 ! Use N=1,2,3,4 for symbol estimation
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endif
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else
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if(hmod.eq.2) nsyncoh=1
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if(hmod.eq.4) nsyncoh=1
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if(hmod.eq.8) nsyncoh=1
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endif
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2020-06-30 16:06:18 -04:00
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do iqorw=itype1,itype2 ! iqorw=1 for QSO mode and iqorw=2 for wspr-type messages
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if( iwspr.lt.2 ) then
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if( single_decode ) then
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fa=max(100,nint(nfqso+1.5*hmod*baud-ntol))
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fb=min(4800,nint(nfqso+1.5*hmod*baud+ntol))
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else
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fa=max(100,nfa)
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fb=min(4800,nfb)
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endif
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elseif( iwspr.eq.2 .and. iqorw.eq.1 ) then
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fa=max(100,nfa)
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fb=nfsplit
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elseif( iwspr.eq.2 .and. iqorw.eq.2 ) then
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fa=nfsplit
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fb=min(4800,nfb)
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endif
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2020-07-04 13:57:51 -04:00
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if(hmod.eq.1) then
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if(ntrperiod.eq.15) minsync=1.15
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if(ntrperiod.gt.15) minsync=1.20
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elseif(hmod.gt.1) then
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minsync=1.5
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endif
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2020-06-27 09:53:11 -04:00
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! Get first approximation of candidate frequencies
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2020-06-30 16:06:18 -04:00
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call get_candidates_fst240(c_bigfft,nfft1,nsps,hmod,fs,fa,fb, &
|
|
|
|
minsync,ncand,candidates,base)
|
2020-06-27 09:53:11 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
ndecodes=0
|
|
|
|
decodes=' '
|
2020-06-27 09:53:11 -04:00
|
|
|
|
2020-07-04 10:15:57 -04:00
|
|
|
isbest=0
|
|
|
|
fc2=0.
|
2020-06-30 16:06:18 -04:00
|
|
|
do icand=1,ncand
|
|
|
|
fc0=candidates(icand,1)
|
|
|
|
detmet=candidates(icand,2)
|
2020-06-27 09:53:11 -04:00
|
|
|
|
|
|
|
! Downconvert and downsample a slice of the spectrum centered on the
|
|
|
|
! rough estimate of the candidates frequency.
|
|
|
|
! Output array c2 is complex baseband sampled at 12000/ndown Sa/sec.
|
|
|
|
! The size of the downsampled c2 array is nfft2=nfft1/ndown
|
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
call fst240_downsample(c_bigfft,nfft1,ndown,fc0,sigbw,c2)
|
|
|
|
|
|
|
|
call timer('sync240 ',0)
|
|
|
|
do isync=0,1
|
|
|
|
if(isync.eq.0) then
|
|
|
|
fc1=0.0
|
|
|
|
if(emedelay.lt.0.1) then ! search offsets from 0 s to 2 s
|
|
|
|
is0=1.5*nspsec
|
|
|
|
ishw=1.5*nspsec
|
|
|
|
else ! search plus or minus 1.5 s centered on emedelay
|
|
|
|
is0=nint(emedelay*nspsec)
|
|
|
|
ishw=1.5*nspsec
|
|
|
|
endif
|
|
|
|
isst=4*hmod
|
|
|
|
ifhw=12
|
|
|
|
df=.1*baud
|
|
|
|
else if(isync.eq.1) then
|
2020-07-04 10:15:57 -04:00
|
|
|
fc1=fc2
|
|
|
|
is0=isbest
|
2020-06-30 16:06:18 -04:00
|
|
|
ishw=4*hmod
|
|
|
|
isst=1*hmod
|
|
|
|
ifhw=7
|
|
|
|
df=.02*baud
|
2020-06-27 09:53:11 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
|
2020-07-04 10:15:57 -04:00
|
|
|
smax=0.0
|
2020-06-30 16:06:18 -04:00
|
|
|
do if=-ifhw,ifhw
|
|
|
|
fc=fc1+df*if
|
|
|
|
do istart=max(1,is0-ishw),is0+ishw,isst
|
2020-07-04 10:15:57 -04:00
|
|
|
call sync_fst240(c2,istart,fc,hmod,nsyncoh,nfft2,nss,fs2,sync)
|
|
|
|
if(sync.gt.smax) then
|
|
|
|
fc2=fc
|
|
|
|
isbest=istart
|
|
|
|
smax=sync
|
2020-06-30 16:06:18 -04:00
|
|
|
endif
|
|
|
|
enddo
|
|
|
|
enddo
|
2020-06-27 09:53:11 -04:00
|
|
|
enddo
|
2020-06-30 16:06:18 -04:00
|
|
|
call timer('sync240 ',1)
|
2020-06-27 09:53:11 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
fc_synced = fc0 + fc2
|
|
|
|
dt_synced = (isbest-fs2)*dt2 !nominal dt is 1 second so frame starts at sample fs2
|
|
|
|
candidates(icand,3)=fc_synced
|
|
|
|
candidates(icand,4)=isbest
|
|
|
|
enddo
|
2020-06-28 16:22:35 -04:00
|
|
|
|
2020-06-27 09:53:11 -04:00
|
|
|
! remove duplicate candidates
|
2020-06-30 16:06:18 -04:00
|
|
|
do icand=1,ncand
|
|
|
|
fc=candidates(icand,3)
|
|
|
|
isbest=nint(candidates(icand,4))
|
|
|
|
do ic2=1,ncand
|
|
|
|
fc2=candidates(ic2,3)
|
|
|
|
isbest2=nint(candidates(ic2,4))
|
|
|
|
if(ic2.ne.icand .and. fc2.gt.0.0) then
|
|
|
|
if(abs(fc2-fc).lt.0.10*baud) then ! same frequency
|
|
|
|
if(abs(isbest2-isbest).le.2) then
|
|
|
|
candidates(ic2,3)=-1
|
|
|
|
endif
|
|
|
|
endif
|
2020-06-27 09:53:11 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
enddo
|
|
|
|
enddo
|
2020-06-30 14:29:32 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
ic=0
|
|
|
|
do icand=1,ncand
|
|
|
|
if(candidates(icand,3).gt.0) then
|
|
|
|
ic=ic+1
|
|
|
|
candidates(ic,:)=candidates(icand,:)
|
2020-06-30 09:42:54 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
enddo
|
|
|
|
ncand=ic
|
|
|
|
xsnr=0.
|
|
|
|
|
|
|
|
do icand=1,ncand
|
|
|
|
sync=candidates(icand,2)
|
|
|
|
fc_synced=candidates(icand,3)
|
|
|
|
isbest=nint(candidates(icand,4))
|
|
|
|
xdt=(isbest-nspsec)/fs2
|
2020-07-04 10:15:57 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
if(ntrperiod.eq.15) xdt=(isbest-real(nspsec)/2.0)/fs2
|
|
|
|
call fst240_downsample(c_bigfft,nfft1,ndown,fc_synced,sigbw,c2)
|
|
|
|
|
|
|
|
do ijitter=0,jittermax
|
|
|
|
if(ijitter.eq.0) ioffset=0
|
|
|
|
if(ijitter.eq.1) ioffset=1
|
|
|
|
if(ijitter.eq.2) ioffset=-1
|
|
|
|
is0=isbest+ioffset
|
|
|
|
if(is0.lt.0) cycle
|
|
|
|
cframe=c2(is0:is0+160*nss-1)
|
|
|
|
bitmetrics=0
|
2020-07-04 10:15:57 -04:00
|
|
|
if(hmod.eq.1) then
|
|
|
|
call get_fst240_bitmetrics(cframe,nss,hmod,nblock,nhicoh,bitmetrics,s4,badsync)
|
|
|
|
else
|
|
|
|
call get_fst240_bitmetrics2(cframe,nss,hmod,nblock,bitmetrics,s4,badsync)
|
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
if(badsync) cycle
|
|
|
|
|
|
|
|
hbits=0
|
|
|
|
where(bitmetrics(:,1).ge.0) hbits=1
|
|
|
|
ns1=count(hbits( 1: 16).eq.(/0,0,0,1,1,0,1,1,0,1,0,0,1,1,1,0/))
|
|
|
|
ns2=count(hbits( 77: 92).eq.(/1,1,1,0,0,1,0,0,1,0,1,1,0,0,0,1/))
|
|
|
|
ns3=count(hbits(153:168).eq.(/0,0,0,1,1,0,1,1,0,1,0,0,1,1,1,0/))
|
|
|
|
ns4=count(hbits(229:244).eq.(/1,1,1,0,0,1,0,0,1,0,1,1,0,0,0,1/))
|
|
|
|
ns5=count(hbits(305:320).eq.(/0,0,0,1,1,0,1,1,0,1,0,0,1,1,1,0/))
|
|
|
|
nsync_qual=ns1+ns2+ns3+ns4+ns5
|
2020-07-04 10:15:57 -04:00
|
|
|
! if(nsync_qual.lt. 46) cycle !### Value ?? ###
|
2020-06-30 16:06:18 -04:00
|
|
|
|
|
|
|
scalefac=2.83
|
|
|
|
llra( 1: 60)=bitmetrics( 17: 76, 1)
|
|
|
|
llra( 61:120)=bitmetrics( 93:152, 1)
|
|
|
|
llra(121:180)=bitmetrics(169:228, 1)
|
|
|
|
llra(181:240)=bitmetrics(245:304, 1)
|
|
|
|
llra=scalefac*llra
|
|
|
|
llrb( 1: 60)=bitmetrics( 17: 76, 2)
|
|
|
|
llrb( 61:120)=bitmetrics( 93:152, 2)
|
|
|
|
llrb(121:180)=bitmetrics(169:228, 2)
|
|
|
|
llrb(181:240)=bitmetrics(245:304, 2)
|
|
|
|
llrb=scalefac*llrb
|
|
|
|
llrc( 1: 60)=bitmetrics( 17: 76, 3)
|
|
|
|
llrc( 61:120)=bitmetrics( 93:152, 3)
|
|
|
|
llrc(121:180)=bitmetrics(169:228, 3)
|
|
|
|
llrc(181:240)=bitmetrics(245:304, 3)
|
|
|
|
llrc=scalefac*llrc
|
|
|
|
llrd( 1: 60)=bitmetrics( 17: 76, 4)
|
|
|
|
llrd( 61:120)=bitmetrics( 93:152, 4)
|
|
|
|
llrd(121:180)=bitmetrics(169:228, 4)
|
|
|
|
llrd(181:240)=bitmetrics(245:304, 4)
|
|
|
|
llrd=scalefac*llrd
|
|
|
|
|
|
|
|
apmag=maxval(abs(llra))*1.1
|
|
|
|
ntmax=nblock+nappasses(nQSOProgress)
|
|
|
|
if(lapcqonly) ntmax=nblock+1
|
2020-07-02 13:30:18 -04:00
|
|
|
if(ndepth.eq.1) ntmax=nblock
|
2020-06-30 16:06:18 -04:00
|
|
|
apmask=0
|
2020-06-30 09:42:54 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
if(iqorw.eq.2) then ! 50-bit msgs, no ap decoding
|
|
|
|
nblock=4
|
|
|
|
ntmax=nblock
|
2020-06-30 09:42:54 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
|
|
|
|
do itry=1,ntmax
|
|
|
|
if(itry.eq.1) llr=llra
|
|
|
|
if(itry.eq.2.and.itry.le.nblock) llr=llrb
|
|
|
|
if(itry.eq.3.and.itry.le.nblock) llr=llrc
|
|
|
|
if(itry.eq.4.and.itry.le.nblock) llr=llrd
|
|
|
|
if(itry.le.nblock) then
|
|
|
|
apmask=0
|
|
|
|
iaptype=0
|
|
|
|
endif
|
|
|
|
napwid=1.2*(4.0*baud*hmod)
|
|
|
|
|
|
|
|
if(itry.gt.nblock) then
|
|
|
|
if(nblock.eq.1) llr=llra
|
|
|
|
if(nblock.gt.1) llr=llrc
|
|
|
|
iaptype=naptypes(nQSOProgress,itry-nblock)
|
|
|
|
if(lapcqonly) iaptype=1
|
|
|
|
if(iaptype.ge.2 .and. apbits(1).gt.1) cycle ! No, or nonstandard, mycall
|
|
|
|
if(iaptype.ge.3 .and. apbits(30).gt.1) cycle ! No, or nonstandard, dxcall
|
|
|
|
if(iaptype.eq.1) then ! CQ
|
|
|
|
apmask=0
|
|
|
|
apmask(1:29)=1
|
|
|
|
llr(1:29)=apmag*mcq(1:29)
|
|
|
|
endif
|
|
|
|
|
|
|
|
if(iaptype.eq.2) then ! MyCall ??? ???
|
|
|
|
apmask=0
|
|
|
|
apmask(1:29)=1
|
|
|
|
llr(1:29)=apmag*apbits(1:29)
|
2020-06-27 09:53:11 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
|
|
|
|
if(iaptype.eq.3) then ! MyCall DxCall ???
|
|
|
|
apmask=0
|
|
|
|
apmask(1:58)=1
|
|
|
|
llr(1:58)=apmag*apbits(1:58)
|
2020-06-27 09:53:11 -04:00
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
|
|
|
|
if(iaptype.eq.4 .or. iaptype.eq.5 .or. iaptype .eq.6) then
|
|
|
|
apmask=0
|
|
|
|
apmask(1:77)=1
|
|
|
|
llr(1:58)=apmag*apbits(1:58)
|
|
|
|
if(iaptype.eq.4) llr(59:77)=apmag*mrrr(1:19)
|
|
|
|
if(iaptype.eq.5) llr(59:77)=apmag*m73(1:19)
|
|
|
|
if(iaptype.eq.6) llr(59:77)=apmag*mrr73(1:19)
|
|
|
|
endif
|
|
|
|
endif
|
|
|
|
|
|
|
|
dmin=0.0
|
|
|
|
nharderrors=-1
|
|
|
|
unpk77_success=.false.
|
|
|
|
if(iqorw.eq.1) then
|
|
|
|
maxosd=2
|
2020-06-30 16:50:50 -04:00
|
|
|
Keff=91
|
2020-06-30 16:06:18 -04:00
|
|
|
norder=3
|
|
|
|
call timer('d240_101',0)
|
|
|
|
call decode240_101(llr,Keff,maxosd,norder,apmask,message101, &
|
|
|
|
cw,ntype,nharderrors,dmin)
|
|
|
|
call timer('d240_101',1)
|
|
|
|
elseif(iqorw.eq.2) then
|
|
|
|
maxosd=2
|
|
|
|
call timer('d240_74 ',0)
|
|
|
|
Keff=64
|
|
|
|
norder=4
|
|
|
|
call decode240_74(llr,Keff,maxosd,norder,apmask,message74,cw, &
|
|
|
|
ntype,nharderrors,dmin)
|
|
|
|
call timer('d240_74 ',1)
|
2020-06-27 09:53:11 -04:00
|
|
|
endif
|
2020-06-30 16:50:50 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
if(nharderrors .ge.0) then
|
2020-07-01 17:42:22 -04:00
|
|
|
if(count(cw.eq.1).eq.0) then
|
|
|
|
nharderrors=-nharderrors
|
|
|
|
cycle
|
|
|
|
endif
|
2020-06-30 16:50:50 -04:00
|
|
|
if(iqorw.eq.1) then
|
2020-06-30 16:06:18 -04:00
|
|
|
write(c77,'(77i1)') mod(message101(1:77)+rvec,2)
|
|
|
|
call unpack77(c77,0,msg,unpk77_success)
|
|
|
|
else
|
|
|
|
write(c77,'(50i1)') message74(1:50)
|
|
|
|
c77(51:77)='000000000000000000000110000'
|
|
|
|
call unpack77(c77,0,msg,unpk77_success)
|
|
|
|
endif
|
|
|
|
if(unpk77_success) then
|
|
|
|
idupe=0
|
|
|
|
do i=1,ndecodes
|
|
|
|
if(decodes(i).eq.msg) idupe=1
|
|
|
|
enddo
|
2020-07-04 10:15:57 -04:00
|
|
|
if(idupe.eq.1) goto 2002
|
2020-06-30 16:06:18 -04:00
|
|
|
ndecodes=ndecodes+1
|
|
|
|
decodes(ndecodes)=msg
|
|
|
|
|
2020-06-30 17:05:52 -04:00
|
|
|
if(iqorw.eq.1) then
|
|
|
|
call get_fst240_tones_from_bits(message101,itone,0)
|
|
|
|
else
|
|
|
|
call get_fst240_tones_from_bits(message74,itone,1)
|
|
|
|
endif
|
2020-06-30 16:06:18 -04:00
|
|
|
xsig=0
|
|
|
|
do i=1,NN
|
|
|
|
xsig=xsig+s4(itone(i),i)**2
|
|
|
|
enddo
|
|
|
|
arg=400.0*(xsig/base)-1.0
|
|
|
|
if(arg.gt.0.0) then
|
|
|
|
xsnr=10*log10(arg)-21.0-11.7*log10(nsps/800.0)
|
|
|
|
else
|
|
|
|
xsnr=-99.9
|
|
|
|
endif
|
2020-07-01 09:20:38 -04:00
|
|
|
else
|
|
|
|
cycle
|
2020-06-30 16:06:18 -04:00
|
|
|
endif
|
|
|
|
nsnr=nint(xsnr)
|
|
|
|
qual=0.
|
|
|
|
fsig=fc_synced - 1.5*hmod*baud
|
2020-07-04 14:06:50 -04:00
|
|
|
! write(21,'(i6,8i6,f7.1,f9.2,f7.1,1x,f7.2,1x,f7.1,1x,a37)') &
|
|
|
|
! nutc,icand,itry,nsyncoh,iaptype,ijitter,ntype,nsync_qual,nharderrors,dmin,sync,xsnr,xdt,fsig,msg
|
|
|
|
! flush(21)
|
2020-06-30 16:06:18 -04:00
|
|
|
call this%callback(nutc,smax1,nsnr,xdt,fsig,msg, &
|
|
|
|
iaptype,qual,ntrperiod,lwspr)
|
|
|
|
goto 2002
|
|
|
|
endif
|
|
|
|
enddo ! metrics
|
|
|
|
enddo ! istart jitter
|
2020-06-30 16:50:50 -04:00
|
|
|
2002 enddo !candidate list
|
2020-06-30 16:06:18 -04:00
|
|
|
enddo ! iqorw
|
2020-06-27 09:53:11 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
return
|
|
|
|
end subroutine decode
|
2020-06-27 09:53:11 -04:00
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
subroutine sync_fst240(cd0,i0,f0,hmod,ncoh,np,nss,fs,sync)
|
2020-06-27 09:53:11 -04:00
|
|
|
|
|
|
|
! Compute sync power for a complex, downsampled FST240 signal.
|
|
|
|
|
2020-06-30 16:06:18 -04:00
|
|
|
include 'fst240/fst240_params.f90'
|
|
|
|
complex cd0(0:np-1)
|
|
|
|
complex, allocatable, save :: csync1(:),csync2(:)
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complex, allocatable, save :: csynct1(:),csynct2(:)
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complex ctwk(8*nss)
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complex z1,z2,z3,z4,z5
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logical first
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integer hmod,isyncword1(0:7),isyncword2(0:7)
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real f0save
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data isyncword1/0,1,3,2,1,0,2,3/
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data isyncword2/2,3,1,0,3,2,0,1/
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data first/.true./,f0save/-99.9/,nss0/-1/
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save first,twopi,dt,fac,f0save,nss0
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p(z1)=(real(z1*fac)**2 + aimag(z1*fac)**2)**0.5 !Compute power
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if(nss.ne.nss0 .and. allocated(csync1)) deallocate(csync1,csync2,csynct1,csynct2)
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if(first .or. nss.ne.nss0) then
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allocate( csync1(8*nss), csync2(8*nss) )
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allocate( csynct1(8*nss), csynct2(8*nss) )
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twopi=8.0*atan(1.0)
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dt=1/fs
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k=1
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phi1=0.0
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phi2=0.0
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do i=0,7
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dphi1=twopi*hmod*(isyncword1(i)-1.5)/real(nss)
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dphi2=twopi*hmod*(isyncword2(i)-1.5)/real(nss)
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do j=1,nss
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csync1(k)=cmplx(cos(phi1),sin(phi1))
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csync2(k)=cmplx(cos(phi2),sin(phi2))
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phi1=mod(phi1+dphi1,twopi)
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phi2=mod(phi2+dphi2,twopi)
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k=k+1
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enddo
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2020-06-27 09:53:11 -04:00
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enddo
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2020-06-30 16:06:18 -04:00
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first=.false.
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nss0=nss
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fac=1.0/(8.0*nss)
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2020-06-27 09:53:11 -04:00
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endif
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2020-06-30 16:06:18 -04:00
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if(f0.ne.f0save) then
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dphi=twopi*f0*dt
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phi=0.0
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do i=1,8*nss
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ctwk(i)=cmplx(cos(phi),sin(phi))
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phi=mod(phi+dphi,twopi)
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enddo
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csynct1=ctwk*csync1
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csynct2=ctwk*csync2
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f0save=f0
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2020-06-27 09:53:11 -04:00
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endif
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2020-06-30 16:06:18 -04:00
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i1=i0 !Costas arrays
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i2=i0+38*nss
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i3=i0+76*nss
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i4=i0+114*nss
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i5=i0+152*nss
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s1=0.0
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s2=0.0
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s3=0.0
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s4=0.0
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s5=0.0
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2020-07-04 10:15:57 -04:00
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if(ncoh.gt.0) then
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nsec=8/ncoh
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do i=1,nsec
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is=(i-1)*ncoh*nss
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z1=0
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if(i1+is.ge.1) then
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z1=sum(cd0(i1+is:i1+is+ncoh*nss-1)*conjg(csynct1(is+1:is+ncoh*nss)))
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endif
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z2=sum(cd0(i2+is:i2+is+ncoh*nss-1)*conjg(csynct2(is+1:is+ncoh*nss)))
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z3=sum(cd0(i3+is:i3+is+ncoh*nss-1)*conjg(csynct1(is+1:is+ncoh*nss)))
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z4=sum(cd0(i4+is:i4+is+ncoh*nss-1)*conjg(csynct2(is+1:is+ncoh*nss)))
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z5=0
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if(i5+is+ncoh*nss-1.le.np) then
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z5=sum(cd0(i5+is:i5+is+ncoh*nss-1)*conjg(csynct1(is+1:is+ncoh*nss)))
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endif
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s1=s1+abs(z1)/(8*nss)
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s2=s2+abs(z2)/(8*nss)
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s3=s3+abs(z3)/(8*nss)
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s4=s4+abs(z4)/(8*nss)
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s5=s5+abs(z5)/(8*nss)
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enddo
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else
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nsub=-ncoh
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nps=nss/nsub
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do i=1,8
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do isub=1,nsub
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is=(i-1)*nss+(isub-1)*nps
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if(i1+is.ge.1) then
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s1=s1+abs(sum(cd0(i1+is:i1+is+nps-1)*conjg(csynct1(is+1:is+nps))))
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endif
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s2=s2+abs(sum(cd0(i2+is:i2+is+nps-1)*conjg(csynct1(is+1:is+nps))))
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s3=s3+abs(sum(cd0(i3+is:i3+is+nps-1)*conjg(csynct1(is+1:is+nps))))
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s4=s4+abs(sum(cd0(i4+is:i4+is+nps-1)*conjg(csynct1(is+1:is+nps))))
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s5=0
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if(i5+is+ncoh*nss-1.le.np) then
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s5=s5+abs(sum(cd0(i5+is:i5+is+nps-1)*conjg(csynct1(is+1:is+nps))))
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endif
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enddo
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enddo
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endif
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2020-06-30 16:06:18 -04:00
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sync = s1+s2+s3+s4+s5
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return
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end subroutine sync_fst240
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2020-06-27 09:53:11 -04:00
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2020-06-30 16:06:18 -04:00
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subroutine fst240_downsample(c_bigfft,nfft1,ndown,f0,sigbw,c1)
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2020-06-27 09:53:11 -04:00
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! Output: Complex data in c(), sampled at 12000/ndown Hz
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2020-06-30 16:06:18 -04:00
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complex c_bigfft(0:nfft1/2)
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complex c1(0:nfft1/ndown-1)
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df=12000.0/nfft1
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i0=nint(f0/df)
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ih=nint( ( f0 + 1.3*sigbw/2.0 )/df)
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nbw=ih-i0+1
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c1=0.
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c1(0)=c_bigfft(i0)
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nfft2=nfft1/ndown
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do i=1,nbw
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if(i0+i.le.nfft1/2) c1(i)=c_bigfft(i0+i)
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if(i0-i.ge.0) c1(nfft2-i)=c_bigfft(i0-i)
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2020-06-27 09:53:11 -04:00
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enddo
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2020-06-30 16:06:18 -04:00
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c1=c1/nfft2
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call four2a(c1,nfft2,1,1,1) !c2c FFT back to time domain
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return
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end subroutine fst240_downsample
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subroutine get_candidates_fst240(c_bigfft,nfft1,nsps,hmod,fs,fa,fb, &
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minsync,ncand,candidates,base)
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complex c_bigfft(0:nfft1/2) !Full length FFT of raw data
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integer hmod !Modulation index (submode)
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integer im(1) !For maxloc
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real candidates(100,4) !Candidate list
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real s(18000) !Low resolution power spectrum
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real s2(18000) !CCF of s() with 4 tones
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real xdb(-3:3) !Model 4-tone CCF peaks
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real minsync
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data xdb/0.25,0.50,0.75,1.0,0.75,0.50,0.25/
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nh1=nfft1/2
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df1=fs/nfft1
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baud=fs/nsps !Keying rate
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df2=baud/2.0
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nd=df2/df1 !s() sums this many bins of big FFT
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ndh=nd/2
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ia=nint(max(100.0,fa)/df2) !Low frequency search limit
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ib=nint(min(4800.0,fb)/df2) !High frequency limit
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signal_bw=4*(12000.0/nsps)*hmod
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analysis_bw=min(4800.0,fb)-max(100.0,fa)
|
2020-07-02 09:45:37 -04:00
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xnoise_bw=10.0*signal_bw !Is this a good compromise?
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if(analysis_bw.gt.xnoise_bw) then
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2020-06-30 16:06:18 -04:00
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ina=ia
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inb=ib
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else
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fcenter=(fa+fb)/2.0 !If noise_bw > analysis_bw,
|
2020-07-02 09:45:37 -04:00
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fl = max(100.0,fcenter-xnoise_bw/2.)/df2 !we'll search over noise_bw
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fh = min(4800.0,fcenter+xnoise_bw/2.)/df2
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2020-06-30 16:06:18 -04:00
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ina=nint(fl)
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inb=nint(fh)
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endif
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2020-06-28 16:22:35 -04:00
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2020-06-30 16:06:18 -04:00
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s=0. !Compute low-resloution power spectrum
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do i=ina,inb ! noise analysis window includes signal analysis window
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j0=nint(i*df2/df1)
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do j=j0-ndh,j0+ndh
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s(i)=s(i) + real(c_bigfft(j))**2 + aimag(c_bigfft(j))**2
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2020-06-28 16:22:35 -04:00
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enddo
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2020-06-30 16:06:18 -04:00
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enddo
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ina=max(ina,1+3*hmod) !Don't run off the ends
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inb=min(inb,18000-3*hmod)
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s2=0.
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do i=ina,inb !Compute CCF of s() and 4 tones
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s2(i)=s(i-hmod*3) + s(i-hmod) +s(i+hmod) +s(i+hmod*3)
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enddo
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call pctile(s2(ina+hmod*3:inb-hmod*3),inb-ina+1-hmod*6,30,base)
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s2=s2/base !Normalize wrt noise level
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ncand=0
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candidates=0
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if(ia.lt.3) ia=3
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if(ib.gt.18000-2) ib=18000-2
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! Find candidates, using the CLEAN algorithm to remove a model of each one
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! from s2() after it has been found.
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pval=99.99
|
2020-07-02 12:54:10 -04:00
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do while(ncand.lt.100)
|
2020-06-30 16:06:18 -04:00
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im=maxloc(s2(ia:ib))
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iploc=ia+im(1)-1 !Index of CCF peak
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pval=s2(iploc) !Peak value
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2020-07-02 12:54:10 -04:00
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if(pval.lt.minsync) exit
|
2020-06-30 16:06:18 -04:00
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if(s2(iploc).gt.thresh) then !Is this a possible candidate?
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do i=-3,+3 !Remove 0.9 of a model CCF at
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k=iploc+2*hmod*i !this frequency from s2()
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if(k.ge.ia .and. k.le.ib) then
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s2(k)=max(0.,s2(k)-0.9*pval*xdb(i))
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endif
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enddo
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ncand=ncand+1
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candidates(ncand,1)=df2*iploc !Candidate frequency
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candidates(ncand,2)=pval !Rough estimate of SNR
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endif
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enddo
|
2020-06-27 09:53:11 -04:00
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2020-06-30 16:06:18 -04:00
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return
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end subroutine get_candidates_fst240
|
2020-06-27 09:53:11 -04:00
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end module fst240_decode
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