mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-03 07:51:16 -05:00
200 lines
6.5 KiB
Fortran
200 lines
6.5 KiB
Fortran
module q65_decode
|
|
|
|
type :: q65_decoder
|
|
procedure(q65_decode_callback), pointer :: callback
|
|
contains
|
|
procedure :: decode
|
|
end type q65_decoder
|
|
|
|
abstract interface
|
|
subroutine q65_decode_callback (this,nutc,sync,nsnr,dt,freq, &
|
|
decoded,nap,ntrperiod)
|
|
import q65_decoder
|
|
implicit none
|
|
class(q65_decoder), intent(inout) :: this
|
|
integer, intent(in) :: nutc
|
|
real, intent(in) :: sync
|
|
integer, intent(in) :: nsnr
|
|
real, intent(in) :: dt
|
|
real, intent(in) :: freq
|
|
character(len=37), intent(in) :: decoded
|
|
integer, intent(in) :: nap
|
|
integer, intent(in) :: ntrperiod
|
|
end subroutine q65_decode_callback
|
|
end interface
|
|
|
|
contains
|
|
|
|
subroutine decode(this,callback,iwave,nutc,ntrperiod,nsubmode,nfqso, &
|
|
ntol,ndepth,lclearave,emedelay,mycall,hiscall,hisgrid,nQSOprogress, &
|
|
ncontest,lapcqonly)
|
|
|
|
! Decodes Q65 signals
|
|
! Input: iwave Raw data, i*2
|
|
! nutc UTC for time-tagging the decode
|
|
! ntrperiod T/R sequence length (s)
|
|
! nsubmode Tone-spacing indicator, 0-4 for A-E
|
|
! nfqso Target signal frequency (Hz)
|
|
! ntol Search range around nfqso (Hz)
|
|
! ndepth Optional decoding level
|
|
! Output: sent to the callback routine for display to user
|
|
|
|
use timer_module, only: timer
|
|
use packjt77
|
|
use, intrinsic :: iso_c_binding
|
|
use q65 !Shared variables
|
|
|
|
parameter (NMAX=300*12000) !Max TRperiod is 300 s
|
|
class(q65_decoder), intent(inout) :: this
|
|
procedure(q65_decode_callback) :: callback
|
|
character(len=12) :: mycall, hiscall !Used for AP decoding
|
|
character(len=6) :: hisgrid
|
|
character*37 decoded !Decoded message
|
|
character*77 c77
|
|
character*78 c78
|
|
integer*2 iwave(NMAX) !Raw data
|
|
real, allocatable :: dd(:) !Raw data
|
|
integer dat4(13) !Decoded message as 12 6-bit integers
|
|
integer apmask1(78),apsymbols1(78)
|
|
integer dgen(13)
|
|
integer codewords(63,206)
|
|
logical lclearave,lapcqonly,unpk77_success
|
|
complex, allocatable :: c00(:) !Analytic signal, 6000 Sa/s
|
|
complex, allocatable :: c0(:) !Analytic signal, 6000 Sa/s
|
|
|
|
idec=-1
|
|
mode65=2**nsubmode
|
|
npts=ntrperiod*12000
|
|
nfft1=ntrperiod*12000
|
|
nfft2=ntrperiod*6000
|
|
if(lclearave) nsave=0
|
|
allocate(dd(npts))
|
|
allocate (c00(0:nfft1-1))
|
|
allocate (c0(0:nfft1-1))
|
|
|
|
if(ntrperiod.eq.15) then
|
|
nsps=1800
|
|
else if(ntrperiod.eq.30) then
|
|
nsps=3600
|
|
else if(ntrperiod.eq.60) then
|
|
nsps=7200
|
|
else if(ntrperiod.eq.120) then
|
|
nsps=16000
|
|
else if(ntrperiod.eq.300) then
|
|
nsps=41472
|
|
else
|
|
stop 'Invalid TR period'
|
|
endif
|
|
baud=12000.0/nsps
|
|
df1=12000.0/nfft1
|
|
this%callback => callback
|
|
nFadingModel=1
|
|
! Set up the codewords for full-AP list decoding
|
|
call q65_set_list(mycall,hiscall,hisgrid,codewords,ncw)
|
|
dgen=0
|
|
call q65_enc(dgen,codewords) !Initialize the Q65 codec
|
|
call timer('sync_q65',0)
|
|
call q65_sync(nutc,iwave,ntrperiod,mode65,codewords,ncw,nsps, &
|
|
nfqso,ntol,ndepth,lclearave,emedelay,xdt,f0,snr1,width,dat4, &
|
|
snr2,idec)
|
|
call timer('sync_q65',1)
|
|
if(idec.ge.0) then
|
|
xdt1=xdt !We have a list-decode result
|
|
f1=f0
|
|
go to 100
|
|
endif
|
|
|
|
if(snr1.lt.2.8) then
|
|
xdt1=0. !No reliable sync, abandon decoding attempt
|
|
f1=0.
|
|
go to 100
|
|
endif
|
|
|
|
jpk0=(xdt+1.0)*6000 !Index of nominal start of signal
|
|
if(ntrperiod.le.30) jpk0=(xdt+0.5)*6000 !For shortest sequences
|
|
if(jpk0.lt.0) jpk0=0
|
|
fac=1.0/32767.0
|
|
dd=fac*iwave(1:npts)
|
|
call ana64(dd,npts,c00) !Convert to complex c00() at 6000 Sa/s
|
|
|
|
! Generate ap symbols as in FT8
|
|
call ft8apset(mycall,hiscall,ncontest,apsym0,aph10)
|
|
where(apsym0.eq.-1) apsym0=0
|
|
|
|
! Main decoding loop starts here
|
|
npasses=2
|
|
if(nQSOprogress.eq.5) npasses=3
|
|
if(lapcqonly) npasses=1
|
|
iaptype=0
|
|
do ipass=0,npasses
|
|
apmask=0 !Try first with no AP information
|
|
apsymbols=0
|
|
|
|
if(ipass.ge.1) then
|
|
! Subsequent passes use AP information appropiate for nQSOprogress
|
|
call q65_ap(nQSOprogress,ipass,ncontest,lapcqonly,iaptype, &
|
|
apsym0,apmask1,apsymbols1)
|
|
write(c78,1050) apmask1
|
|
1050 format(78i1)
|
|
read(c78,1060) apmask
|
|
1060 format(13b6.6)
|
|
write(c78,1050) apsymbols1
|
|
read(c78,1060) apsymbols
|
|
if(iaptype.eq.4) then
|
|
do j=1,3
|
|
ng15=32401+j
|
|
write(c78(60:74),'(b15.15)') ng15
|
|
read(c78,1060) dgen
|
|
call q65_enc(dgen,codewords(1,j))
|
|
enddo
|
|
endif
|
|
endif
|
|
|
|
call timer('q65loops',0)
|
|
call q65_loops(c00,npts/2,nsps/2,mode65,nsubmode,ndepth,jpk0, &
|
|
xdt,f0,iaptype,xdt1,f1,snr2,dat4,idec)
|
|
call timer('q65loops',1)
|
|
if(idec.gt.0) go to 100 !Successful decode, we're done
|
|
enddo
|
|
|
|
! No single-transmission decode.
|
|
if(iand(ndepth,16).eq.16) then
|
|
call q65_avg2(ntrperiod,ntol,baud,nsubmode,nQSOprogress,lapcqonly, &
|
|
ibwa,ibwb,codewords,ncw,xdt,f0,snr1,snr2,dat4,idec)
|
|
endif
|
|
|
|
100 decoded=' '
|
|
if(idec.gt.0) then
|
|
|
|
! ------------------------------------------------------
|
|
! idec Meaning
|
|
! ------------------------------------------------------
|
|
! -1: No decode
|
|
! 1: Decode with AP for "MyCall DxCall ?"
|
|
! 2: Decode without AP information
|
|
! 3: Decode with AP for "CQ ? ?"
|
|
! 4: Decode with AP for "MyCall ? ?"
|
|
! ------------------------------------------------------
|
|
! Second digit (if any) is number of sequences averaged.
|
|
! ------------------------------------------------------
|
|
|
|
! Unpack decoded message for display to user
|
|
write(c77,1000) dat4(1:12),dat4(13)/2
|
|
1000 format(12b6.6,b5.5)
|
|
call unpack77(c77,0,decoded,unpk77_success) !Unpack to get msgsent
|
|
nsnr=nint(snr2)
|
|
call this%callback(nutc,sync,nsnr,xdt1,f1,decoded, &
|
|
idec,ntrperiod)
|
|
else
|
|
! Report sync, even if no decode.
|
|
nsnr=db(snr1) - 35.0
|
|
idec=-1
|
|
call this%callback(nutc,sync,nsnr,xdt1,f1,decoded, &
|
|
idec,ntrperiod)
|
|
endif
|
|
|
|
return
|
|
end subroutine decode
|
|
|
|
end module q65_decode
|