Added I decoder and reorganized the E selection code

This commit is contained in:
Jordan Sherer
2019-12-09 14:00:23 -05:00
parent f706685cc9
commit 5215fd324d
15 changed files with 645 additions and 69 deletions
+57
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@@ -7,6 +7,7 @@ subroutine multimode_decoder(ss,id2,params,nfsample)
use js8b_decode
use js8c_decode
use js8e_decode
use js8i_decode
include 'jt9com.f90'
include 'timer_common.inc'
@@ -27,6 +28,10 @@ subroutine multimode_decoder(ss,id2,params,nfsample)
integer :: decoded
end type counting_js8e_decoder
type, extends(js8i_decoder) :: counting_js8i_decoder
integer :: decoded
end type counting_js8i_decoder
real ss(184,NSMAX)
logical baddata,newdat65,newdat9,single_decode,bVHF,bad0,newdat,trydecode
integer*2 id0(NTMAX*12000)
@@ -40,6 +45,7 @@ subroutine multimode_decoder(ss,id2,params,nfsample)
type(counting_js8b_decoder) :: my_js8b
type(counting_js8c_decoder) :: my_js8c
type(counting_js8e_decoder) :: my_js8e
type(counting_js8i_decoder) :: my_js8i
!cast C character arrays to Fortran character strings
datetime=transfer(params%datetime, datetime)
@@ -53,6 +59,7 @@ subroutine multimode_decoder(ss,id2,params,nfsample)
my_js8b%decoded = 0
my_js8c%decoded = 0
my_js8e%decoded = 0
my_js8i%decoded = 0
single_decode=iand(params%nexp_decode,32).ne.0
bVHF=iand(params%nexp_decode,64).ne.0
@@ -74,6 +81,29 @@ subroutine multimode_decoder(ss,id2,params,nfsample)
write(*,1012) params%nsubmode, params%nsubmodes
1012 format('<DecodeStarted>',2i4)
if(params%nmode.eq.8 .and. (params%nsubmode.eq.8 .or. iand(params%nsubmodes, 16).eq.16)) then
! We're in JS8 mode I
call timer('decjs8i ',0)
newdat=params%newdat
write(*,*) '<DecodeDebug> mode I decode started'
! copy the relevant frames for decoding
pos = max(0,params%kposI)
sz = max(0,params%kszI)
id0=0
id0(1:sz+1)=id2(pos+1:pos+sz+1)
call my_js8i%decode(js8i_decoded,id0,params%nQSOProgress,params%nfqso, &
params%nftx,newdat,params%nutc,params%nfa,params%nfb, &
params%nexp_decode,params%ndepth,logical(params%nagain), &
logical(params%lft8apon),logical(params%lapcqonly),params%napwid, &
mycall,mygrid,hiscall,hisgrid)
write(*,*) '<DecodeDebug> mode I decode finished'
call timer('decjs8i ',1)
endif
if(params%nmode.eq.8 .and. (params%nsubmode.eq.4 .or. iand(params%nsubmodes, 8).eq.8)) then
! We're in JS8 mode E
call timer('decjs8e ',0)
@@ -229,6 +259,7 @@ contains
if(submode.eq.1) m=' B '
if(submode.eq.2) m=' C '
if(submode.eq.4) m=' E '
if(submode.eq.8) m=' I '
i0=index(decoded0,';')
@@ -377,4 +408,30 @@ contains
return
end subroutine js8e_decoded
subroutine js8i_decoded (this,sync,snr,dt,freq,decoded,nap,qual)
use js8i_decode
implicit none
class(js8i_decoder), intent(inout) :: this
real, intent(in) :: sync
integer, intent(in) :: snr
real, intent(in) :: dt
real, intent(in) :: freq
character(len=37), intent(in) :: decoded
integer, intent(in) :: nap
real, intent(in) :: qual
integer :: submode
save
submode=8
call js8_decoded(sync, snr, dt, freq, decoded, nap, qual, submode)
select type(this)
type is (counting_js8i_decoder)
this%decoded = this%decoded + 1
end select
return
end subroutine js8i_decoded
end subroutine multimode_decoder
+37
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@@ -0,0 +1,37 @@
!parameter (NSPS=480) !Samples per symbol at 12000 S/s
!parameter (NTXDUR=5) !TX Duration in Seconds
!parameter (NDOWNSPS=16) !Downsampled samples per symbol
!parameter (AZ=6.0) !Near dupe sync spacing
!parameter (NDD=136) !Downconverted FFT Bins - 100 Bins
!parameter (JZ=62) !Sync Search Space over +/- 2.5s relative to 0.5s TX start time. 2.48 = 62/4/(12000/1920) ?
parameter (NSPS=384, NTXDUR=4, NDOWNSPS=12, NDD=125, JZ=250) ! 250 Hz 31.25 baud 60 wpm -18.0dB (1.0Eb/N0) 2.52s
! parameter (NSPS=384, NTXDUR=5, NDOWNSPS=12, NDD=125, JZ=116) ! 250 Hz 31.25 baud 48 wpm -18.0dB (1.0Eb/N0) 2.52s
! parameter (NSPS=480, NTXDUR=5, NDOWNSPS=12, NDD=125, JZ=116) ! 200 Hz 25 baud 48 wpm -19.0dB (1.0Eb/N0) 3.16s
! parameter (NSPS=480, NTXDUR=6, NDOWNSPS=20, NDD=150, JZ=116) ! 200 Hz 25 baud 40 wpm -19.0dB (1.0Eb/N0) 3.16s
! parameter (NSPS=500, NTXDUR=6, NDOWNSPS=20, NDD=144, JZ=116) ! 192 Hz 24 baud 40 wpm -19.4dB (1.0Eb/N0) 3.29s
! parameter (NSPS=600, NTXDUR=6, NDOWNSPS=24, NDD=120, JZ=172) ! 160 Hz 20 baud 40 wpm -20.0dB (1.0Eb/N0) 3.95s
! parameter (NSPS=768, NTXDUR=8, NDOWNSPS=24, NDD=125, JZ=116) ! 125 Hz 15.625 baud 32 wpm -21.0dB (1.0Eb/N0) 5.05s
! parameter (NSPS=800, NTXDUR=8, NDOWNSPS=24, NDD=100, JZ=116) ! 120 Hz 15 baud 32 wpm -21.2dB (1.0Eb/N0) 5.26s
! parameter (NSPS=960, NTXDUR=8, NDOWNSPS=24, NDD=100, JZ=116) ! 100 Hz 12.50 baud 32 wpm -22.0dB (1.0Eb/N0) 5.92s
! parameter (NSPS=1200, NTXDUR=10, NDOWNSPS=20, NDD=100, JZ=116) ! 80 Hz 10 baud 24 wpm -23.0dB (1.0Eb/N0) 7.90s
! parameter (NSPS=1920, NTXDUR=15, NDOWNSPS=32, NDD=100, JZ=116) ! 50 Hz 6.250 baud 16 wpm -25.0dB (1.0Eb/N0) 12.64s
! parameter (NSPS=3840, NTXDUR=30, NDOWNSPS=32, NDD=94, JZ=116) ! 24 Hz 3.125 baud 8 wpm -28.0dB (1.0Eb/N0) 25.28s
! parameter (NSPS=4000, NTXDUR=28, NDOWNSPS=20, NDD=90, JZ=32) ! 24 Hz 3 baud 8 wpm -28.2dB (1.0Eb/N0) 26.33s
parameter (AZ=12000.0/(1.0*NSPS)*0.8d0) !Dedupe overlap in Hz
parameter (ASTART=0.1) !Start delay in seconds
parameter (ASYNCMIN=1.5) !Minimum Sync
parameter (KK=87) !Information bits (75 + CRC12)
parameter (ND=58) !Data symbols
parameter (NS=21) !Sync symbols (3 @ Costas 7x7)
parameter (NN=NS+ND) !Total channel symbols (79)
parameter (NZ=NSPS*NN) !Samples in full 15 s waveform (151,680)
parameter (NMAX=NTXDUR*12000) !Samples in iwave (180,000)
parameter (NFFT1=2*NSPS, NH1=NFFT1/2) !Length of FFTs for symbol spectra
parameter (NSTEP=NSPS/4) !Rough time-sync step size
parameter (NHSYM=NMAX/NSTEP-3) !Number of symbol spectra (1/4-sym steps)
parameter (NDOWN=NSPS/NDOWNSPS) !Downsample factor to 32 samples per symbol
parameter (NQSYMBOL=NDOWNSPS/4) !Downsample factor of a quarter symbol
+238
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@@ -0,0 +1,238 @@
program ldpcsim174js8
! End to end test of the (174,75)/crc12 encoder and decoder.
use crc
use packjt
include 'js8_params.f90'
include 'js8i_params.f90'
character*22 msg,msgsent,msgreceived
character*8 arg
character*6 grid
integer*1, allocatable :: codeword(:), decoded(:), message(:)
integer*1, target:: i1Msg8BitBytes(11)
integer*1 msgbits(87)
integer*1 apmask(174), cw(174)
integer*2 checksum
integer*4 i4Msg6BitWords(13)
integer colorder(174)
integer nerrtot(174),nerrdec(174),nmpcbad(87)
logical checksumok,fsk,bpsk
real*8, allocatable :: rxdata(:)
real, allocatable :: llr(:)
data colorder/ &
0, 1, 2, 3, 30, 4, 5, 6, 7, 8, 9, 10, 11, 32, 12, 40, 13, 14, 15, 16,&
17, 18, 37, 45, 29, 19, 20, 21, 41, 22, 42, 31, 33, 34, 44, 35, 47, 51, 50, 43,&
36, 52, 63, 46, 25, 55, 27, 24, 23, 53, 39, 49, 59, 38, 48, 61, 60, 57, 28, 62,&
56, 58, 65, 66, 26, 70, 64, 69, 68, 67, 74, 71, 54, 76, 72, 75, 78, 77, 80, 79,&
73, 83, 84, 81, 82, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,&
100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,&
120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,&
140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,&
160,161,162,163,164,165,166,167,168,169,170,171,172,173/
nerrtot=0
nerrdec=0
nmpcbad=0 ! Used to collect the number of errors in the message+crc part of the codeword
nargs=iargc()
if(nargs.ne.4) then
print*,'Usage: ldpcsim niter ndepth #trials s '
print*,'eg: ldpcsim 10 2 1000 0.84'
print*,'belief propagation iterations: niter, ordered-statistics depth: ndepth'
print*,'If s is negative, then value is ignored and sigma is calculated from SNR.'
return
endif
call getarg(1,arg)
read(arg,*) max_iterations
call getarg(2,arg)
read(arg,*) ndepth
call getarg(3,arg)
read(arg,*) ntrials
call getarg(4,arg)
read(arg,*) s
fsk=.false.
bpsk=.true.
! don't count crc bits as data bits
N=174
K=87
! scale Eb/No for a (174,87) code
rate=real(K)/real(N)
write(*,*) "rate: ",rate
write(*,*) "niter= ",max_iterations," s= ",s
allocate ( codeword(N), decoded(K), message(K) )
allocate ( rxdata(N), llr(N) )
msg="0123456789012"
! msg="G4WJS K9AN EN50"
call packmsg(msg,i4Msg6BitWords,itype,.false.) !Pack into 12 6-bit bytes
call unpackmsg(i4Msg6BitWords,msgsent,.false.,grid) !Unpack to get msgsent
write(*,*) "message sent ",msgsent
i4=0
ik=0
im=0
do i=1,12
nna=i4Msg6BitWords(i)
do j=1, 6
ik=ik+1
i4=i4+i4+iand(1,ishft(nna,j-6))
i4=iand(i4,255)
if(ik.eq.8) then
im=im+1
! if(i4.gt.127) i4=i4-256
i1Msg8BitBytes(im)=i4
ik=0
endif
enddo
enddo
i1Msg8BitBytes(10:11)=0
checksum = crc12 (c_loc (i1Msg8BitBytes), 11)
checksum = xor(checksum, 42) ! TODO: jsherer - could change the crc here
! For reference, the next 3 lines show how to check the CRC
i1Msg8BitBytes(10)=checksum/256
i1Msg8BitBytes(11)=iand(checksum,transfer(255,0_2))
checksumok = crc12_check(c_loc (i1Msg8BitBytes), 11)
if( checksumok ) write(*,*) 'Good checksum'
! K=87, For now:
! msgbits(1:72) JT message bits
! msgbits(73:75) 3 free message bits (set to 0)
! msgbits(76:87) CRC12
mbit=0
do i=1, 9
i1=i1Msg8BitBytes(i)
do ibit=1,8
mbit=mbit+1
msgbits(mbit)=iand(1,ishft(i1,ibit-8))
enddo
enddo
msgbits(73:75)=0 ! the three extra message bits go here
i1=i1Msg8BitBytes(10) ! First 4 bits of crc12 are LSB of this byte
do ibit=1,4
msgbits(75+ibit)=iand(1,ishft(i1,ibit-4))
enddo
i1=i1Msg8BitBytes(11) ! Now shift in last 8 bits of the CRC
do ibit=1,8
msgbits(79+ibit)=iand(1,ishft(i1,ibit-8))
enddo
write(*,*) 'message'
write(*,'(11(8i1,1x))') msgbits
call encode174(msgbits,codeword)
call init_random_seed()
! call sgran()
write(*,*) 'codeword'
write(*,'(22(8i1,1x))') codeword
write(*,*) "Es/N0 SNR2500 ngood nundetected nbadcrc sigma"
do idb = 20,-10,-1
!do idb = -3,-3,-1
db=idb/2.0-1.0
sigma=1/sqrt( 2*(10**(db/10.0)) )
ngood=0
nue=0
nbadcrc=0
nberr=0
do itrial=1, ntrials
! Create a realization of a noisy received word
do i=1,N
if( bpsk ) then
rxdata(i) = 2.0*codeword(i)-1.0 + sigma*gran()
elseif( fsk ) then
if( codeword(i) .eq. 1 ) then
r1=(1.0 + sigma*gran())**2 + (sigma*gran())**2
r2=(sigma*gran())**2 + (sigma*gran())**2
elseif( codeword(i) .eq. 0 ) then
r2=(1.0 + sigma*gran())**2 + (sigma*gran())**2
r1=(sigma*gran())**2 + (sigma*gran())**2
endif
! rxdata(i)=0.35*(sqrt(r1)-sqrt(r2))
! rxdata(i)=0.35*(exp(r1)-exp(r2))
rxdata(i)=0.12*(log(r1)-log(r2))
endif
enddo
nerr=0
do i=1,N
if( rxdata(i)*(2*codeword(i)-1.0) .lt. 0 ) nerr=nerr+1
enddo
if(nerr.ge.1) nerrtot(nerr)=nerrtot(nerr)+1
nberr=nberr+nerr
! Correct signal normalization is important for this decoder.
rxav=sum(rxdata)/N
rx2av=sum(rxdata*rxdata)/N
rxsig=sqrt(rx2av-rxav*rxav)
rxdata=rxdata/rxsig
! To match the metric to the channel, s should be set to the noise standard deviation.
! For now, set s to the value that optimizes decode probability near threshold.
! The s parameter can be tuned to trade a few tenth's dB of threshold for an order of
! magnitude in UER
if( s .lt. 0 ) then
ss=sigma
else
ss=s
endif
llr=2.0*rxdata/(ss*ss)
nap=0 ! number of AP bits
llr(colorder(174-87+1:174-87+nap)+1)=5*(2.0*msgbits(1:nap)-1.0)
apmask=0
apmask(colorder(174-87+1:174-87+nap)+1)=1
! max_iterations is max number of belief propagation iterations
call bpdecode174(llr, apmask, max_iterations, decoded, cw, nharderrors,niterations)
if( ndepth .ge. 0 .and. nharderrors .lt. 0 ) call osd174(llr, apmask, ndepth, decoded, cw, nharderrors, dmin)
! If the decoder finds a valid codeword, nharderrors will be .ge. 0.
if( nharderrors .ge. 0 ) then
call extractmessage174(decoded,msgreceived,ncrcflag)
if( ncrcflag .ne. 1 ) then
nbadcrc=nbadcrc+1
endif
nueflag=0
nerrmpc=0
do i=1,K ! find number of errors in message+crc part of codeword
if( msgbits(i) .ne. decoded(i) ) then
nueflag=1
nerrmpc=nerrmpc+1
endif
enddo
if(nerrmpc.ge.1) nmpcbad(nerrmpc)=nmpcbad(nerrmpc)+1
if( ncrcflag .eq. 1 ) then
if( nueflag .eq. 0 ) then
ngood=ngood+1
if(nerr.ge.1) nerrdec(nerr)=nerrdec(nerr)+1
else if( nueflag .eq. 1 ) then
nue=nue+1;
endif
endif
endif
enddo
baud=12000.0/NSPS
snr2500=db+10.0*log10((baud/2500.0))
pberr=real(nberr)/(real(ntrials*N))
write(*,"(f4.1,4x,f5.1,1x,i8,1x,i8,1x,i8,8x,f5.2,8x,e10.3)") db,snr2500,ngood,nue,nbadcrc,ss,pberr
enddo
open(unit=23,file='nerrhisto.dat',status='unknown')
do i=1,174
write(23,'(i4,2x,i10,i10,f10.2)') i,nerrdec(i),nerrtot(i),real(nerrdec(i))/real(nerrtot(i)+1e-10)
enddo
close(23)
open(unit=25,file='nmpcbad.dat',status='unknown')
do i=1,87
write(25,'(i4,2x,i10)') i,nmpcbad(i)
enddo
close(25)
end program ldpcsim174js8
+152
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@@ -0,0 +1,152 @@
module js8i_decode
type :: js8i_decoder
procedure(js8i_decode_callback), pointer :: callback
contains
procedure :: decode
end type js8i_decoder
abstract interface
subroutine js8i_decode_callback (this,sync,snr,dt,freq,decoded,nap,qual)
import js8i_decoder
implicit none
class(js8i_decoder), intent(inout) :: this
real, intent(in) :: sync
integer, intent(in) :: snr
real, intent(in) :: dt
real, intent(in) :: freq
character(len=37), intent(in) :: decoded
integer, intent(in) :: nap
real, intent(in) :: qual
end subroutine js8i_decode_callback
end interface
contains
subroutine decode(this,callback,iwave,nQSOProgress,nfqso,nftx,newdat, &
nutc,nfa,nfb,nexp_decode,ndepth,nagain,lft8apon,lapcqonly,napwid, &
mycall12,mygrid6,hiscall12,hisgrid6)
! use wavhdr
use timer_module, only: timer
! type(hdr) h
use js8i_module
class(js8i_decoder), intent(inout) :: this
procedure(js8i_decode_callback) :: callback
real s(NH1,NHSYM)
real sbase(NH1)
real candidate(3,200)
real dd(NMAX)
logical, intent(in) :: lft8apon,lapcqonly,nagain
logical newdat,lsubtract,ldupe,bcontest
character*12 mycall12, hiscall12
character*6 mygrid6,hisgrid6
integer*2 iwave(NMAX)
integer apsym(KK)
character datetime*13,message*22,msg37*37
character*22 allmessages(100)
integer allsnrs(100)
save s,dd
bcontest=iand(nexp_decode,128).ne.0
this%callback => callback
write(datetime,1001) nutc !### TEMPORARY ###
1001 format("000000_",i6.6)
call ft8apset(mycall12,mygrid6,hiscall12,hisgrid6,bcontest,apsym,iaptype)
dd=iwave
ndecodes=0
allmessages=' '
allsnrs=0
ifa=nfa
ifb=nfb
if(nagain) then
ifa=nfqso-10
ifb=nfqso+10
endif
! For now:
! ndepth=1: no subtraction, 1 pass, belief propagation only
! ndepth=2: subtraction, 3 passes, belief propagation only
! ndepth=3: subtraction, 3 passes, bp+osd
if(ndepth.eq.1) npass=1
if(ndepth.ge.2) npass=3
do ipass=1,npass
newdat=.true. ! Is this a problem? I hijacked newdat.
syncmin=ASYNCMIN
if(ipass.eq.1) then
lsubtract=.true.
if(ndepth.eq.1) lsubtract=.false.
elseif(ipass.eq.2) then
n2=ndecodes
if(ndecodes.eq.0) cycle
lsubtract=.true.
elseif(ipass.eq.3) then
if((ndecodes-n2).eq.0) cycle
lsubtract=.false.
endif
call timer('syncjs8 ',0)
call syncjs8(dd,ifa,ifb,syncmin,nfqso,s,candidate,ncand,sbase)
call timer('syncjs8 ',1)
if(NWRITELOG.eq.1) then
write(*,*) '<DecodeDebug>', ncand, "candidates"
flush(6)
endif
do icand=1,ncand
sync=candidate(3,icand)
f1=candidate(1,icand)
xdt=candidate(2,icand)
xbase=10.0**(0.1*(sbase(nint(f1/(12000.0/NFFT1)))-40.0)) ! 3.125Hz
nsnr0=min(99,nint(10.0*log10(sync) - 25.5)) !### empirical ###
if(NWRITELOG.eq.1) then
write(*,*) '<DecodeDebug> candidate', icand, 'f1', f1, 'sync', sync, 'xdt', xdt, 'xbase', xbase
flush(6)
endif
call timer('js8dec ',0)
call js8dec(dd,newdat,nQSOProgress,nfqso,nftx,ndepth,lft8apon, &
lapcqonly,napwid,lsubtract,nagain,iaptype,mycall12,mygrid6, &
hiscall12,bcontest,sync,f1,xdt,xbase,apsym,nharderrors,dmin, &
nbadcrc,iappass,iera,msg37,xsnr)
message=msg37(1:22) !###
nsnr=nint(xsnr)
xdt=xdt-ASTART
hd=nharderrors+dmin
if(NWRITELOG.eq.1) then
write(*,*) '<DecodeDebug> candidate', icand, 'hard', hd, 'nbadcrc', nbadcrc
flush(6)
endif
call timer('js8dec ',1)
if(nbadcrc.eq.0) then
ldupe=.false.
do id=1,ndecodes
if(message.eq.allmessages(id).and.nsnr.le.allsnrs(id)) ldupe=.true.
enddo
if(.not.ldupe) then
ndecodes=ndecodes+1
allmessages(ndecodes)=message
allsnrs(ndecodes)=nsnr
endif
if(.not.ldupe .and. associated(this%callback)) then
qual=1.0-(nharderrors+dmin)/60.0 ! scale qual to [0.0,1.0]
call this%callback(sync,nsnr,xdt,f1,msg37,iaptype,qual)
endif
endif
if(NWRITELOG.eq.1) then
write(*,*) '<DecodeDebug> ---'
flush(6)
endif
enddo
enddo
return
end subroutine decode
end module js8i_decode
+13
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@@ -0,0 +1,13 @@
module js8i_module
include 'js8/js8_params.f90'
include 'js8/js8i_params.f90'
contains
include 'js8/baselinejs8.f90'
include 'js8/syncjs8.f90'
include 'js8/js8_downsample.f90'
include 'js8/syncjs8d.f90'
include 'js8/genjs8refsig.f90'
include 'js8/subtractjs8.f90'
include 'js8/js8dec.f90'
end module js8i_module
+2
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@@ -23,10 +23,12 @@
integer(c_int) :: kposB
integer(c_int) :: kposC
integer(c_int) :: kposE
integer(c_int) :: kposI
integer(c_int) :: kszA
integer(c_int) :: kszB
integer(c_int) :: kszC
integer(c_int) :: kszE
integer(c_int) :: kszI
integer(c_int) :: nzhsym
integer(c_int) :: nsubmode
integer(c_int) :: nsubmodes