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Add ft4 files in lib/ft4.

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This commit is contained in:
Steve Franke 2019-01-25 16:01:34 -06:00
parent 3bdbf19d1d
commit 66e3f11fba
9 changed files with 871 additions and 318 deletions
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21
CMakeLists.txt
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@ -463,7 +463,7 @@ set (wsjt_FSRCS
lib/genmsk_128_90.f90
lib/genmsk40.f90
lib/fsk4hf/genft2.f90
lib/fsk4hf/genft4.f90
lib/ft4/genft4.f90
lib/genqra64.f90
lib/ft8/genft8refsig.f90
lib/genwspr.f90
@ -509,8 +509,10 @@ set (wsjt_FSRCS
lib/msk144signalquality.f90
lib/msk144sim.f90
lib/mskrtd.f90
lib/fsk4hf/ft4sim.f90
lib/fsk4hf/ft4d.f90
lib/fsk4hf/ft2sim.f90
lib/fsk4hf/ft2d.f90
lib/ft4/ft4sim.f90
lib/ft4/ft4d.f90
lib/ft2/cdatetime.f90
lib/ft2/ft2_decode.f90
lib/77bit/my_hash.f90
@ -553,10 +555,13 @@ set (wsjt_FSRCS
lib/sync4.f90
lib/sync64.f90
lib/sync65.f90
lib/ft4/getcandidates4.f90
lib/fsk4hf/getcandidates2.f90
lib/ft2/getcandidates2a.f90
lib/ft4/syncft4.f90
lib/ft8/sync8.f90
lib/ft8/sync8d.f90
lib/ft4/sync4d.f90
lib/sync9.f90
lib/sync9f.f90
lib/sync9w.f90
@ -1265,10 +1270,16 @@ target_link_libraries (ft8sim wsjt_fort wsjt_cxx)
add_executable (msk144sim lib/msk144sim.f90 wsjtx.rc)
target_link_libraries (msk144sim wsjt_fort wsjt_cxx)
add_executable (ft4sim lib/fsk4hf/ft4sim.f90 wsjtx.rc)
add_executable (ft2sim lib/fsk4hf/ft2sim.f90 wsjtx.rc)
target_link_libraries (ft2sim wsjt_fort wsjt_cxx)
add_executable (ft2d lib/fsk4hf/ft2d.f90 wsjtx.rc)
target_link_libraries (ft2d wsjt_fort wsjt_cxx)
add_executable (ft4sim lib/ft4/ft4sim.f90 wsjtx.rc)
target_link_libraries (ft4sim wsjt_fort wsjt_cxx)
add_executable (ft4d lib/fsk4hf/ft4d.f90 wsjtx.rc)
add_executable (ft4d lib/ft4/ft4d.f90 wsjtx.rc)
target_link_libraries (ft4d wsjt_fort wsjt_cxx)
endif(WSJT_BUILD_UTILS)

592
lib/fsk4hf/ft4d.f90
View File

@ -1,317 +1,329 @@
program ft4d
use crc
use packjt77
include 'ft4_params.f90'
character arg*8,message*37,c77*77,infile*80,fname*16,datetime*11
character*37 decodes(100)
character*120 data_dir
character*90 dmsg
complex cd2(0:NMAX/16-1) !Complex waveform
complex cb(0:NMAX/16-1)
complex cd(0:76*20-1) !Complex waveform
complex c3(0:19),c2(0:19),c1(0:19),c0(0:19)
complex ccor(0:3,76)
complex csum,cterm,cc0,cc1,cc2,cc3,csync1,csync2
complex csync(12)
real*8 fMHz
use crc
use packjt77
include 'ft4_params.f90'
character arg*8,message*37,c77*77,infile*80,fname*16,datetime*11
character*37 decodes(100)
character*120 data_dir
character*90 dmsg
complex cd2(0:NMAX/16-1) !Complex waveform
complex cb(0:NMAX/16-1)
complex cd(0:76*20-1) !Complex waveform
complex csum,cterm
complex ctwk(80),ctwk2(80)
complex csymb(20)
complex cs(0:3,NN)
real s4(0:3,NN)
real a(5)
real rxdata(128),llr(128) !Soft symbols
real llr2(128)
real sbits(152),sbits1(152),sbits3(152)
real ps(0:8191),psbest(0:8191)
real candidates(100,2)
real savg(NH1),sbase(NH1)
integer ihdr(11)
integer*2 iwave(NMAX) !Generated full-length waveform
integer*1 message77(77),apmask(128),cw(128)
integer*1 hbits(152),hbits1(152),hbits3(152)
integer*1 s12(12)
logical unpk77_success
data s12/0,0,0,1,1,1,1,1,1,0,0,0/
real*8 fMHz
real ps(0:8191),psbest(0:8191)
real bmeta(152),bmetb(152),bmetc(152)
real s(NH1,NHSYM)
real a(5)
real llr(128),llr2(128),llra(128),llrb(128),llrc(128)
real s2(0:255)
real candidate(3,100)
real savg(NH1),sbase(NH1)
integer ihdr(11)
integer icos4(0:3)
integer*2 iwave(NMAX) !Generated full-length waveform
integer*1 message77(77),apmask(128),cw(128)
integer*1 hbits(152),hbits1(152),hbits3(152)
integer*1 s12(12)
integer graymap(0:3)
integer ip(1)
logical unpk77_success
logical one(0:511,0:7) ! 256 4-symbol sequences, 8 bits
data s12/1,1,1,2,2,2,2,2,2,1,1,1/
data icos4/0,1,3,2/
data graymap/0,1,3,2/
save one
fs=12000.0/NDOWN !Sample rate
dt=1/fs !Sample interval after downsample (s)
tt=NSPS*dt !Duration of "itone" symbols (s)
baud=1.0/tt !Keying rate for "itone" symbols (baud)
txt=NZ*dt !Transmission length (s)
twopi=8.0*atan(1.0)
h=1.000 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading)
fs=12000.0/NDOWN !Sample rate
dt=1/fs !Sample interval after downsample (s)
tt=NSPS*dt !Duration of "itone" symbols (s)
baud=1.0/tt !Keying rate for "itone" symbols (baud)
txt=NZ*dt !Transmission length (s)
twopi=8.0*atan(1.0)
h=1.0 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading)
dphi=twopi/2*baud*h*dt*16 ! dt*16 is samp interval after downsample
dphi0=-3*dphi
dphi1=-dphi
dphi2=+dphi
dphi3=+3*dphi
phi0=0.0
phi1=0.0
phi2=0.0
phi3=0.0
do i=0,19
c3(i)=cmplx(cos(phi3),sin(phi3))
c2(i)=cmplx(cos(phi2),sin(phi2))
c1(i)=cmplx(cos(phi1),sin(phi1))
c0(i)=cmplx(cos(phi0),sin(phi0))
phi3=mod(phi3+dphi3,twopi)
phi2=mod(phi2+dphi2,twopi)
phi1=mod(phi1+dphi1,twopi)
phi0=mod(phi0+dphi0,twopi)
enddo
the=twopi*h/2.0
cc3=cmplx(cos(3*the),+sin(3*the))
cc2=cmplx(cos(the),+sin(the))
cc1=cmplx(cos(the),-sin(the))
cc0=cmplx(cos(3*the),-sin(3*the))
one=.false.
do i=0,255
do j=0,7
if(iand(i,2**j).ne.0) one(i,j)=.true.
enddo
enddo
nargs=iargc()
if(nargs.lt.1) then
print*,'Usage: ft4d [-a <data_dir>] [-f fMHz] file1 [file2 ...]'
go to 999
endif
iarg=1
data_dir="."
call getarg(iarg,arg)
if(arg(1:2).eq.'-a') then
call getarg(iarg+1,data_dir)
iarg=iarg+2
endif
call getarg(iarg,arg)
if(arg(1:2).eq.'-f') then
call getarg(iarg+1,arg)
read(arg,*) fMHz
iarg=iarg+2
endif
ncoh=1
do ifile=iarg,nargs
call getarg(ifile,infile)
j2=index(infile,'.wav')
open(10,file=infile,status='old',access='stream')
read(10,end=999) ihdr,iwave
read(infile(j2-4:j2-1),*) nutc
datetime=infile(j2-11:j2-1)
close(10)
candidate=0.0
ncand=0
nfqso=1500
nfa=500
nfb=2700
syncmin=1.0
maxcand=100
! call syncft4(iwave,nfa,nfb,syncmin,nfqso,maxcand,s,candidate,ncand,sbase)
call getcandidates4(iwave,375.0,3000.0,0.2,2200.0,100,savg,candidate,ncand,sbase)
ndecodes=0
do icand=1,ncand
f0=candidate(1,icand)-1.5*37.5
xsnr=1.0
if( f0.le.375.0 .or. f0.ge.(5000.0-375.0) ) cycle
call ft4_downsample(iwave,f0,cd2) ! downsample from 320 Sa/Symbol to 20 Sa/Symbol
sum2=sum(cd2*conjg(cd2))/(20.0*76)
if(sum2.gt.0.0) cd2=cd2/sqrt(sum2)
nargs=iargc()
if(nargs.lt.1) then
print*,'Usage: ft4d [-a <data_dir>] [-f fMHz] file1 [file2 ...]'
go to 999
endif
iarg=1
data_dir="."
call getarg(iarg,arg)
if(arg(1:2).eq.'-a') then
call getarg(iarg+1,data_dir)
iarg=iarg+2
endif
call getarg(iarg,arg)
if(arg(1:2).eq.'-f') then
call getarg(iarg+1,arg)
read(arg,*) fMHz
iarg=iarg+2
endif
ncoh=1
do ifile=iarg,nargs
call getarg(ifile,infile)
j2=index(infile,'.wav')
open(10,file=infile,status='old',access='stream')
read(10,end=999) ihdr,iwave
read(infile(j2-4:j2-1),*) nutc
datetime=infile(j2-11:j2-1)
close(10)
candidates=0.0
ncand=0
call getcandidates2(iwave,375.0,3000.0,0.2,2200.0,100,savg,candidates,ncand,sbase)
ndecodes=0
do icand=1,ncand
f0=candidates(icand,1)
xsnr=1.0
if( f0.le.375.0 .or. f0.ge.(5000.0-375.0) ) cycle
call ft4_downsample(iwave,f0,cd2) ! downsample from 320s/Symbol to 20s/Symbol
s2=sum(cd2*conjg(cd2))/(20.0*76)
if(s2.gt.0.0) cd2=cd2/sqrt(s2)
! 750 samples/second here
ibest=-1
sybest=-99.
dfbest=-1.
do if=-30,+30
df=if
a=0.
a(1)=-df
call twkfreq1(cd2,NMAX/16,fs,a,cb)
do istart=0,380
csync1=0.
cterm=1
do ib=1,12
i1=(ib-1)*20+istart
if(s12(ib).eq.0) then
csync1=csync1+sum(cb(i1:i1+19)*conjg(c0(0:19)))*cterm
cterm=cterm*conjg(cc0)
else
csync1=csync1+sum(cb(i1:i1+19)*conjg(c3(0:19)))*cterm
cterm=cterm*conjg(cc3)
endif
enddo
if(abs(csync1).gt.sybest) then
ibest=istart
sybest=abs(csync1)
dfbest=df
endif
enddo
enddo
a=0.
!dfbest=1500.0-f0
a(1)=-dfbest
call twkfreq1(cd2,NMAX/16,fs,a,cb)
ibest=-1
smax=-99.
dfbest=-1.
do idf=-90,+90,5
df=idf
a=0.
a(1)=df
ctwk=1.
call twkfreq1(ctwk,80,fs,a,ctwk2)
do istart=0,315
call sync4d(cd2,istart,ctwk2,1,sync)
if(sync.gt.smax) then
smax=sync
ibest=istart
dfbest=df
endif
enddo
enddo
f0=f0+dfbest
!f0=1443.75
call ft4_downsample(iwave,f0,cb) ! downsample from 320s/Symbol to 20s/Symbol
sum2=sum(abs(cb)**2)/(20.0*76)
if(sum2.gt.0.0) cb=cb/sqrt(sum2)
!ibest=208
ib=ibest
cd=cb(ibest:ibest+76*20-1)
do k=1,NN
i1=(k-1)*20
csymb=cd(i1:i1+19)
call four2a(csymb,20,1,-1,1)
cs(0:3,k)=csymb(1:4)/1e2
s4(0:3,k)=abs(csymb(1:4))
enddo
cd=cb(ib:ib+76*20-1)
do nseq=1,1
if( nseq.eq.1 ) then ! noncoherent single-symbol detection
sbits1=0.0
do isym=1,76
ib=(isym-1)*20
ccor(3,isym)=sum(cd(ib:ib+19)*conjg(c3(0:19)))
ccor(2,isym)=sum(cd(ib:ib+19)*conjg(c2(0:19)))
ccor(1,isym)=sum(cd(ib:ib+19)*conjg(c1(0:19)))
ccor(0,isym)=sum(cd(ib:ib+19)*conjg(c0(0:19)))
sbits1(2*isym-1)= max(abs(ccor(2,isym)),abs(ccor(3,isym)))- &
max(abs(ccor(0,isym)),abs(ccor(1,isym)))
sbits1(2*isym) = max(abs(ccor(1,isym)),abs(ccor(2,isym)))- &
max(abs(ccor(0,isym)),abs(ccor(3,isym)))
hbits1(2*isym-1:2*isym)=0
if(sbits1(2*isym-1).gt.0) hbits1(2*isym-1)=1
if(sbits1(2*isym ).gt.0) hbits1(2*isym )=1
enddo
sbits=sbits1
hbits=hbits1
sbits3=sbits1
hbits3=hbits1
elseif( nseq.ge.2 ) then
nbit=2*nseq-1
numseq=2**(nbit)
ps=0
do ibit=nbit/2+1,144-nbit/2
ps=0.0
pmax=0.0
do iseq=0,numseq-1
csum=0.0
cterm=1.0
k=1
do i=nbit-1,0,-1
ibb=iand(iseq/(2**i),1)
csum=csum+ccor(ibb,ibit-(nbit/2+1)+k)*cterm
if(ibb.eq.0) cterm=cterm*cc0
if(ibb.eq.1) cterm=cterm*cc1
k=k+1
enddo
ps(iseq)=abs(csum)
if( ps(iseq) .gt. pmax ) then
pmax=ps(iseq)
ibflag=1
endif
enddo
if( ibflag .eq. 1 ) then
psbest=ps
ibflag=0
endif
call getbitmetric(2**(nbit/2),psbest,numseq,sbits3(ibit))
hbits3(ibit)=0
if(sbits3(ibit).gt.0) hbits3(ibit)=1
enddo
sbits=sbits3
hbits=hbits3
endif
nsync_qual=count(hbits(1:24).eq.(/0,0,0,0,0,0,1,0,1,0,1,0,1,0,1,0,1,0,0,0,0,0,0,0/))
! if(nsync_qual.lt.10) exit
rxdata=sbits(25:152)
rxav=sum(rxdata(1:128))/128.0
rx2av=sum(rxdata(1:128)*rxdata(1:128))/128.0
rxsig=sqrt(rx2av-rxav*rxav)
rxdata=rxdata/rxsig
sigma=0.80
llr(1:128)=2*rxdata/(sigma*sigma)
apmask=0
max_iterations=40
do ibias=0,0
llr2=llr
if(ibias.eq.1) llr2=llr+0.4
if(ibias.eq.2) llr2=llr-0.4
call bpdecode128_90(llr2,apmask,max_iterations,message77,cw,nharderror,niterations)
if(nharderror.ge.0) exit
enddo
if(sum(message77).eq.0) cycle
if( nharderror.ge.0 ) then
write(c77,'(77i1)') message77(1:77)
call unpack77(c77,1,message,unpk77_success)
idupe=0
do i=1,ndecodes
if(decodes(i).eq.message) idupe=1
enddo
if(idupe.eq.1) goto 888
ndecodes=ndecodes+1
decodes(ndecodes)=message
nsnr=nint(xsnr)
freq=f0+dfbest
1210 format(a11,2i4,f6.2,f12.7,2x,a22,i3)
write(*,1212) datetime(8:11),nsnr,ibest/750.0,freq,message,'*',nseq,nharderror,nsync_qual
1212 format(a4,i4,2x,f5.3,f11.1,2x,a22,a1,i5,i5,i5)
goto 888
endif
enddo ! nseq
888 continue
enddo !candidate list
enddo !files
! sync quality check
is1=0
is2=0
is3=0
do k=1,4
ip=maxloc(s4(:,k))
if(icos4(k-1).eq.(ip(1)-1)) is1=is1+1
ip=maxloc(s4(:,k+36))
if(icos4(k-1).eq.(ip(1)-1)) is2=is2+1
ip=maxloc(s4(:,k+72))
if(icos4(k-1).eq.(ip(1)-1)) is3=is3+1
enddo
! hard sync sum - max is 12
nsync=is1+is2+is3
write(*,1120)
do nseq=1,3
if(nseq.eq.1) nsym=1
if(nseq.eq.2) nsym=2
if(nseq.eq.3) nsym=4
nt=2**(2*nsym)
do ks=1,76,nsym
amax=-1.0
do i=0,nt-1
i1=i/64
i2=iand(i,63)/16
i3=iand(i,15)/4
i4=iand(i,3)
if(nsym.eq.1) then
s2(i)=abs(cs(graymap(i4),ks))
elseif(nsym.eq.2) then
s2(i)=abs(cs(graymap(i3),ks)+cs(graymap(i4),ks+1))
elseif(nsym.eq.4) then
s2(i)=abs(cs(graymap(i1),ks ) + &
cs(graymap(i2),ks+1) + &
cs(graymap(i3),ks+2) + &
cs(graymap(i4),ks+3) &
)
else
print*,"Error - nsym must be 1, 2, or 4."
endif
enddo
ipt=1+(ks-1)*2
if(nsym.eq.1) ibmax=1
if(nsym.eq.2) ibmax=3
if(nsym.eq.4) ibmax=7
do ib=0,ibmax
bm=maxval(s2(0:nt-1),one(0:nt-1,ibmax-ib)) - &
maxval(s2(0:nt-1),.not.one(0:nt-1,ibmax-ib))
if(ipt+ib .gt.152) cycle
if(nsym.eq.1) then
bmeta(ipt+ib)=bm
elseif(nsym.eq.2) then
bmetb(ipt+ib)=bm
elseif(nsym.eq.4) then
bmetc(ipt+ib)=bm
endif
enddo
enddo
enddo
call normalizebmet(bmeta,152)
call normalizebmet(bmetb,152)
call normalizebmet(bmetc,152)
hbits=0
where(bmeta.ge.0) hbits=1
ns1=count(hbits( 1: 8).eq.(/0,0,0,1,1,0,1,1/))
ns2=count(hbits( 73: 80).eq.(/0,0,0,1,1,0,1,1/))
ns3=count(hbits(145:152).eq.(/0,0,0,1,1,0,1,1/))
nsync_qual=ns1+ns2+ns3
sigma=0.7
llra(1:64)=bmeta(9:72)
llra(65:128)=bmeta(81:144)
llra=2*llra/sigma**2
llrb(1:64)=bmetb(9:72)
llrb(65:128)=bmetb(81:144)
llrb=2*llrb/sigma**2
llrc(1:64)=bmetc(9:72)
llrc(65:128)=bmetc(81:144)
llrc=2*llrc/sigma**2
do isd=1,3
if(isd.eq.1) llr=llra
if(isd.eq.2) llr=llrb
if(isd.eq.3) llr=llrc
apmask=0
max_iterations=40
do ibias=0,0
llr2=llr
if(ibias.eq.1) llr2=llr+0.4
if(ibias.eq.2) llr2=llr-0.4
call bpdecode128_90(llr2,apmask,max_iterations,message77,cw,nharderror,niterations)
if(nharderror.ge.0) exit
enddo
if(sum(message77).eq.0) cycle
if( nharderror.ge.0 ) then
write(c77,'(77i1)') message77(1:77)
call unpack77(c77,1,message,unpk77_success)
idupe=0
do i=1,ndecodes
if(decodes(i).eq.message) idupe=1
enddo
if(idupe.eq.1) cycle
ndecodes=ndecodes+1
decodes(ndecodes)=message
nsnr=nint(xsnr)
write(*,1212) datetime(8:11),nsnr,ibest/750.0,f0,message,'*',nharderror,nsync_qual,isd,niterations
1212 format(a4,i4,2x,f5.3,f11.1,2x,a22,a1,i5,i5,i5,i5)
endif
enddo ! sequence estimation
enddo !candidate list
enddo !files
write(*,1120)
1120 format("<DecodeFinished>")
999 end program ft4d
subroutine getbitmetric(ib,ps,ns,xmet)
real ps(0:ns-1)
xm1=0
xm0=0
do i=0,ns-1
if( iand(i/ib,1) .eq. 1 .and. ps(i) .gt. xm1 ) xm1=ps(i)
if( iand(i/ib,1) .eq. 0 .and. ps(i) .gt. xm0 ) xm0=ps(i)
enddo
xmet=xm1-xm0
return
real ps(0:ns-1)
xm1=0
xm0=0
do i=0,ns-1
if( iand(i/ib,1) .eq. 1 .and. ps(i) .gt. xm1 ) xm1=ps(i)
if( iand(i/ib,1) .eq. 0 .and. ps(i) .gt. xm0 ) xm0=ps(i)
enddo
xmet=xm1-xm0
return
end subroutine getbitmetric
subroutine downsample2(ci,f0,co)
parameter(NI=144*160,NH=NI/2,NO=NI/16) ! downsample from 200 samples per symbol to 10
complex ci(0:NI-1),ct(0:NI-1)
complex co(0:NO-1)
fs=12000.0
df=fs/NI
ct=ci
call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain
i0=nint(f0/df)
ct=cshift(ct,i0)
co=0.0
co(0)=ct(0)
b=8.0
do i=1,NO/2
arg=(i*df/b)**2
filt=exp(-arg)
co(i)=ct(i)*filt
co(NO-i)=ct(NI-i)*filt
enddo
co=co/NO
call four2a(co,NO,1,1,1) !c2c FFT back to time domain
return
end subroutine downsample2
subroutine downsample4(ci,f0,co)
parameter(NI=144*160,NH=NI/2,NO=NI/16) ! downsample from 200 samples per symbol to 10
complex ci(0:NI-1),ct(0:NI-1)
complex co(0:NO-1)
fs=12000.0
df=fs/NI
ct=ci
call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain
i0=nint(f0/df)
ct=cshift(ct,i0)
co=0.0
co(0)=ct(0)
b=8.0
do i=1,NO/2
arg=(i*df/b)**2
filt=exp(-arg)
co(i)=ct(i)*filt
co(NO-i)=ct(NI-i)*filt
enddo
co=co/NO
call four2a(co,NO,1,1,1) !c2c FFT back to time domain
return
end subroutine downsample4
subroutine ft4_downsample(iwave,f0,c)
! Input: i*2 data in iwave() at sample rate 12000 Hz
! Output: Complex data in c(), sampled at 1200 Hz
include 'ft4_params.f90'
parameter (NFFT2=NMAX/16)
integer*2 iwave(NMAX)
complex c(0:NMAX/16-1)
complex c1(0:NFFT2-1)
complex cx(0:NMAX/2)
real x(NMAX)
equivalence (x,cx)
include 'ft4_params.f90'
parameter (NFFT2=NMAX/16)
integer*2 iwave(NMAX)
complex c(0:NMAX/16-1)
complex c1(0:NFFT2-1)
complex cx(0:NMAX/2)
real x(NMAX)
equivalence (x,cx)
BW=6.0*75
df=12000.0/NMAX
x=iwave
call four2a(x,NMAX,1,-1,0) !r2c FFT to freq domain
ibw=nint(BW/df)
i0=nint(f0/df)
c1=0.
c1(0)=cx(i0)
do i=1,NFFT2/2
arg=(i-1)*df/bw
win=exp(-arg*arg)
c1(i)=cx(i0+i)*win
c1(NFFT2-i)=cx(i0-i)*win
enddo
c1=c1/NFFT2
call four2a(c1,NFFT2,1,1,1) !c2c FFT back to time domain
c=c1(0:NMAX/16-1)
return
BW=6.0*75
df=12000.0/NMAX
x=iwave
call four2a(x,NMAX,1,-1,0) !r2c FFT to freq domain
ibw=nint(BW/df)
i0=nint(f0/df)
c1=0.
c1(0)=cx(i0)
do i=1,NFFT2/2
arg=(i-1)*df/bw
win=exp(-arg*arg)
c1(i)=cx(i0+i)*win
c1(NFFT2-i)=cx(i0-i)*win
enddo
c1=c1/NFFT2
call four2a(c1,NFFT2,1,1,1) !c2c FFT back to time domain
c=c1(0:NMAX/16-1)
return
end subroutine ft4_downsample

8
lib/fsk4hf/ft4_params.f90 → lib/ft4/ft4_params.f90
View File

@ -6,9 +6,9 @@ parameter (ND=64) !Data symbols
parameter (NS=12) !Sync symbols (12)
parameter (NN=NS+ND) !Total channel symbols (76)
parameter (NSPS=320) !Samples per symbol at 12000 S/s
parameter (NZ=NSPS*NN) !Samples in full 1.92 s waveform (23040)
parameter (NMAX=2.5*12000) !Samples in iwave (36,000)
parameter (NFFT1=640, NH1=NFFT1/2) !Length of FFTs for symbol spectra
parameter (NSTEP=NSPS/4) !Rough time-sync step size
parameter (NZ=NSPS*NN) !Samples in full 2.03 s message frame (24320)
parameter (NMAX=2.5*12000) !Samples in iwave (30,000)
parameter (NFFT1=1280, NH1=NFFT1/2) !Length of FFTs for symbol spectra
parameter (NSTEP=NSPS/4) !Coarse time-sync step size
parameter (NHSYM=NMAX/NSTEP-3) !Number of symbol spectra (1/4-sym steps)
parameter (NDOWN=16) !Downsample factor

329
lib/ft4/ft4d.f90 Normal file
View File

@ -0,0 +1,329 @@
program ft4d
use crc
use packjt77
include 'ft4_params.f90'
character arg*8,message*37,c77*77,infile*80,fname*16,datetime*11
character*37 decodes(100)
character*120 data_dir
character*90 dmsg
complex cd2(0:NMAX/16-1) !Complex waveform
complex cb(0:NMAX/16-1)
complex cd(0:76*20-1) !Complex waveform
complex csum,cterm
complex ctwk(80),ctwk2(80)
complex csymb(20)
complex cs(0:3,NN)
real s4(0:3,NN)
real*8 fMHz
real ps(0:8191),psbest(0:8191)
real bmeta(152),bmetb(152),bmetc(152)
real s(NH1,NHSYM)
real a(5)
real llr(128),llr2(128),llra(128),llrb(128),llrc(128)
real s2(0:255)
real candidate(3,100)
real savg(NH1),sbase(NH1)
integer ihdr(11)
integer icos4(0:3)
integer*2 iwave(NMAX) !Generated full-length waveform
integer*1 message77(77),apmask(128),cw(128)
integer*1 hbits(152),hbits1(152),hbits3(152)
integer*1 s12(12)
integer graymap(0:3)
integer ip(1)
logical unpk77_success
logical one(0:511,0:7) ! 256 4-symbol sequences, 8 bits
data s12/1,1,1,2,2,2,2,2,2,1,1,1/
data icos4/0,1,3,2/
data graymap/0,1,3,2/
save one
fs=12000.0/NDOWN !Sample rate
dt=1/fs !Sample interval after downsample (s)
tt=NSPS*dt !Duration of "itone" symbols (s)
baud=1.0/tt !Keying rate for "itone" symbols (baud)
txt=NZ*dt !Transmission length (s)
twopi=8.0*atan(1.0)
h=1.0 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading)
one=.false.
do i=0,255
do j=0,7
if(iand(i,2**j).ne.0) one(i,j)=.true.
enddo
enddo
nargs=iargc()
if(nargs.lt.1) then
print*,'Usage: ft4d [-a <data_dir>] [-f fMHz] file1 [file2 ...]'
go to 999
endif
iarg=1
data_dir="."
call getarg(iarg,arg)
if(arg(1:2).eq.'-a') then
call getarg(iarg+1,data_dir)
iarg=iarg+2
endif
call getarg(iarg,arg)
if(arg(1:2).eq.'-f') then
call getarg(iarg+1,arg)
read(arg,*) fMHz
iarg=iarg+2
endif
ncoh=1
do ifile=iarg,nargs
call getarg(ifile,infile)
j2=index(infile,'.wav')
open(10,file=infile,status='old',access='stream')
read(10,end=999) ihdr,iwave
read(infile(j2-4:j2-1),*) nutc
datetime=infile(j2-11:j2-1)
close(10)
candidate=0.0
ncand=0
nfqso=1500
nfa=500
nfb=2700
syncmin=1.0
maxcand=100
! call syncft4(iwave,nfa,nfb,syncmin,nfqso,maxcand,s,candidate,ncand,sbase)
call getcandidates4(iwave,375.0,3000.0,0.2,2200.0,100,savg,candidate,ncand,sbase)
ndecodes=0
do icand=1,ncand
f0=candidate(1,icand)-1.5*37.5
xsnr=1.0
if( f0.le.375.0 .or. f0.ge.(5000.0-375.0) ) cycle
call ft4_downsample(iwave,f0,cd2) ! downsample from 320 Sa/Symbol to 20 Sa/Symbol
sum2=sum(cd2*conjg(cd2))/(20.0*76)
if(sum2.gt.0.0) cd2=cd2/sqrt(sum2)
! 750 samples/second here
ibest=-1
smax=-99.
dfbest=-1.
do idf=-90,+90,5
df=idf
a=0.
a(1)=df
ctwk=1.
call twkfreq1(ctwk,80,fs,a,ctwk2)
do istart=0,315
call sync4d(cd2,istart,ctwk2,1,sync)
if(sync.gt.smax) then
smax=sync
ibest=istart
dfbest=df
endif
enddo
enddo
f0=f0+dfbest
f0=1443.75
call ft4_downsample(iwave,f0,cb) ! downsample from 320s/Symbol to 20s/Symbol
sum2=sum(abs(cb)**2)/(20.0*76)
if(sum2.gt.0.0) cb=cb/sqrt(sum2)
ibest=208
cd=cb(ibest:ibest+76*20-1)
do k=1,NN
i1=(k-1)*20
csymb=cd(i1:i1+19)
call four2a(csymb,20,1,-1,1)
cs(0:3,k)=csymb(1:4)/1e2
s4(0:3,k)=abs(csymb(1:4))
enddo
! sync quality check
is1=0
is2=0
is3=0
do k=1,4
ip=maxloc(s4(:,k))
if(icos4(k-1).eq.(ip(1)-1)) is1=is1+1
ip=maxloc(s4(:,k+36))
if(icos4(k-1).eq.(ip(1)-1)) is2=is2+1
ip=maxloc(s4(:,k+72))
if(icos4(k-1).eq.(ip(1)-1)) is3=is3+1
enddo
! hard sync sum - max is 12
nsync=is1+is2+is3
do nseq=1,3
if(nseq.eq.1) nsym=1
if(nseq.eq.2) nsym=2
if(nseq.eq.3) nsym=4
nt=2**(2*nsym)
do ks=1,76,nsym
amax=-1.0
do i=0,nt-1
i1=i/64
i2=iand(i,63)/16
i3=iand(i,15)/4
i4=iand(i,3)
if(nsym.eq.1) then
s2(i)=abs(cs(graymap(i4),ks))
elseif(nsym.eq.2) then
s2(i)=abs(cs(graymap(i3),ks)+cs(graymap(i4),ks+1))
elseif(nsym.eq.4) then
s2(i)=abs(cs(graymap(i1),ks ) + &
cs(graymap(i2),ks+1) + &
cs(graymap(i3),ks+2) + &
cs(graymap(i4),ks+3) &
)
else
print*,"Error - nsym must be 1, 2, or 4."
endif
enddo
ipt=1+(ks-1)*2
if(nsym.eq.1) ibmax=1
if(nsym.eq.2) ibmax=3
if(nsym.eq.4) ibmax=7
do ib=0,ibmax
bm=maxval(s2(0:nt-1),one(0:nt-1,ibmax-ib)) - &
maxval(s2(0:nt-1),.not.one(0:nt-1,ibmax-ib))
if(ipt+ib .gt.152) cycle
if(nsym.eq.1) then
bmeta(ipt+ib)=bm
elseif(nsym.eq.2) then
bmetb(ipt+ib)=bm
elseif(nsym.eq.4) then
bmetc(ipt+ib)=bm
endif
enddo
enddo
enddo
call normalizebmet(bmeta,152)
call normalizebmet(bmetb,152)
call normalizebmet(bmetc,152)
hbits=0
where(bmeta.ge.0) hbits=1
ns1=count(hbits( 1: 8).eq.(/0,0,0,1,1,0,1,1/))
ns2=count(hbits( 73: 80).eq.(/0,0,0,1,1,0,1,1/))
ns3=count(hbits(145:152).eq.(/0,0,0,1,1,0,1,1/))
nsync_qual=ns1+ns2+ns3
sigma=0.7
llra(1:64)=bmeta(9:72)
llra(65:128)=bmeta(81:144)
llra=2*llra/sigma**2
llrb(1:64)=bmetb(9:72)
llrb(65:128)=bmetb(81:144)
llrb=2*llrb/sigma**2
llrc(1:64)=bmetc(9:72)
llrc(65:128)=bmetc(81:144)
llrc=2*llrc/sigma**2
do isd=1,3
if(isd.eq.1) llr=llra
if(isd.eq.2) llr=llrb
if(isd.eq.3) llr=llrc
apmask=0
max_iterations=40
do ibias=0,0
llr2=llr
if(ibias.eq.1) llr2=llr+0.4
if(ibias.eq.2) llr2=llr-0.4
call bpdecode128_90(llr2,apmask,max_iterations,message77,cw,nharderror,niterations)
if(nharderror.ge.0) exit
enddo
if(sum(message77).eq.0) cycle
if( nharderror.ge.0 ) then
write(c77,'(77i1)') message77(1:77)
call unpack77(c77,1,message,unpk77_success)
idupe=0
do i=1,ndecodes
if(decodes(i).eq.message) idupe=1
enddo
if(idupe.eq.1) cycle
ndecodes=ndecodes+1
decodes(ndecodes)=message
nsnr=nint(xsnr)
write(*,1212) datetime(8:11),nsnr,ibest/750.0,f0,message,'*',nharderror,nsync_qual,isd,niterations
1212 format(a4,i4,2x,f5.3,f11.1,2x,a22,a1,i5,i5,i5,i5)
endif
enddo ! sequence estimation
enddo !candidate list
enddo !files
write(*,1120)
1120 format("<DecodeFinished>")
999 end program ft4d
subroutine getbitmetric(ib,ps,ns,xmet)
real ps(0:ns-1)
xm1=0
xm0=0
do i=0,ns-1
if( iand(i/ib,1) .eq. 1 .and. ps(i) .gt. xm1 ) xm1=ps(i)
if( iand(i/ib,1) .eq. 0 .and. ps(i) .gt. xm0 ) xm0=ps(i)
enddo
xmet=xm1-xm0
return
end subroutine getbitmetric
subroutine downsample4(ci,f0,co)
parameter(NI=144*160,NH=NI/2,NO=NI/16) ! downsample from 200 samples per symbol to 10
complex ci(0:NI-1),ct(0:NI-1)
complex co(0:NO-1)
fs=12000.0
df=fs/NI
ct=ci
call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain
i0=nint(f0/df)
ct=cshift(ct,i0)
co=0.0
co(0)=ct(0)
b=8.0
do i=1,NO/2
arg=(i*df/b)**2
filt=exp(-arg)
co(i)=ct(i)*filt
co(NO-i)=ct(NI-i)*filt
enddo
co=co/NO
call four2a(co,NO,1,1,1) !c2c FFT back to time domain
return
end subroutine downsample4
subroutine ft4_downsample(iwave,f0,c)
! Input: i*2 data in iwave() at sample rate 12000 Hz
! Output: Complex data in c(), sampled at 1200 Hz
include 'ft4_params.f90'
parameter (NFFT2=NMAX/16)
integer*2 iwave(NMAX)
complex c(0:NMAX/16-1)
complex c1(0:NFFT2-1)
complex cx(0:NMAX/2)
real x(NMAX)
equivalence (x,cx)
BW=6.0*75
df=12000.0/NMAX
x=iwave
call four2a(x,NMAX,1,-1,0) !r2c FFT to freq domain
ibw=nint(BW/df)
i0=nint(f0/df)
c1=0.
c1(0)=cx(i0)
do i=1,NFFT2/2
arg=(i-1)*df/bw
win=exp(-arg*arg)
c1(i)=cx(i0+i)*win
c1(NFFT2-i)=cx(i0-i)*win
enddo
c1=c1/NFFT2
call four2a(c1,NFFT2,1,1,1) !c2c FFT back to time domain
c=c1(0:NMAX/16-1)
return
end subroutine ft4_downsample

8
lib/fsk4hf/ft4sim.f90 → lib/ft4/ft4sim.f90
View File

@ -18,6 +18,8 @@ program ft4sim
integer itone(NN)
integer*1 msgbits(77)
integer*2 iwave(NMAX) !Generated full-length waveform
integer icos4(4)
data icos4/0,1,3,2/
! Get command-line argument(s)
nargs=iargc()
@ -48,7 +50,7 @@ program ft4sim
twopi=8.0*atan(1.0)
fs=12000.0 !Sample rate (Hz)
dt=1.0/fs !Sample interval (s)
hmod=1.000 !Modulation index (0.5 is MSK, 1.0 is FSK)
hmod=1.0 !Modulation index (0.5 is MSK, 1.0 is FSK)
tt=NSPS*dt !Duration of symbols (s)
baud=1.0/tt !Keying rate (baud)
txt=NZ*dt !Transmission length (s)
@ -114,10 +116,6 @@ program ft4sim
c0=cshift(c0,-k)
ia=k
do i=0,NMAX-1
write(21,*) i,real(c0(i)),imag(c0(i)),dphi(i)
enddo
do ifile=1,nfiles
c=c0
if(fspread.ne.0.0 .or. delay.ne.0.0) call watterson(c,NMAX,NWAVE,fs,delay,fspread)

19
lib/fsk4hf/genft4.f90 → lib/ft4/genft4.f90
View File

@ -15,12 +15,15 @@ subroutine genft4(msg0,ichk,msgsent,i4tone)
character*37 message !Message to be generated
character*37 msgsent !Message as it will be received
character*77 c77
integer*4 i4tone(76)
integer*4 i4tone(76),itmp(64)
integer*1 codeword(128)
integer*1 msgbits(77)
integer*1 s12(12)
integer icos4(4)
real*8 xi(864),xq(864),pi,twopi
data s12/0,0,0,3,3,3,3,3,3,0,0,0/
! data s12/1,1,1,2,2,2,2,2,2,1,1,1/
data icos4/0,1,3,2/
logical unpk77_success
twopi=8.*atan(1.0)
@ -56,13 +59,17 @@ subroutine genft4(msg0,ichk,msgsent,i4tone)
! 10 3
!Create 144-bit channel vector:
i4tone(1:12)=s12
do i=1,64
is=codeword(2*i)+2*codeword(2*i-1)
if(is.le.1) i4tone(12+i)=is
if(is.eq.2) i4tone(12+i)=3
if(is.eq.3) i4tone(12+i)=2
if(is.le.1) itmp(i)=is
if(is.eq.2) itmp(i)=3
if(is.eq.3) itmp(i)=2
enddo
i4tone(1:4)=icos4
i4tone(5:36)=itmp(1:32)
i4tone(37:40)=icos4
i4tone(41:72)=itmp(33:64)
i4tone(73:76)=icos4
999 return
end subroutine genft4

13
lib/fsk4hf/getcandidates4.f90 → lib/ft4/getcandidates4.f90
View File

@ -1,9 +1,7 @@
subroutine getcandidates4(id,fa,fb,syncmin,nfqso,maxcand,savg,candidate, &
ncand,sbase)
! For now, hardwired to find the largest peak in the average spectrum
include 'ft2_params.f90'
include 'ft4_params.f90'
real s(NH1,NHSYM)
real savg(NH1),savsm(NH1)
real sbase(NH1)
@ -11,9 +9,7 @@ subroutine getcandidates4(id,fa,fb,syncmin,nfqso,maxcand,savg,candidate, &
complex cx(0:NH1)
real candidate(3,maxcand)
integer*2 id(NMAX)
integer*1 s8(8)
integer indx(NH1)
data s8/0,1,1,1,0,0,1,0/
equivalence (x,cx)
! Compute symbol spectra, stepping by NSTEP steps.
@ -33,10 +29,9 @@ subroutine getcandidates4(id,fa,fb,syncmin,nfqso,maxcand,savg,candidate, &
savg=savg + s(1:NH1,j) !Average spectrum
enddo
savsm=0.
do i=2,NH1-1
savsm(i)=sum(savg(i-1:i+1))/3.
do i=6,NH1-5
savsm(i)=sum(savg(i-5:i+5))/11.
enddo
nfa=fa/df
nfb=fb/df
np=nfb-nfa+1
@ -58,6 +53,8 @@ subroutine getcandidates4(id,fa,fb,syncmin,nfqso,maxcand,savg,candidate, &
if(xmax.gt.1.2) then
ncand=ncand+1
candidate(1,ncand)=f0
candidate(2,ncand)=-99.9
candidate(3,ncand)=xmax
endif
return
end subroutine getcandidates4

54
lib/ft4/sync4d.f90 Normal file
View File

@ -0,0 +1,54 @@
subroutine sync4d(cd0,i0,ctwk,itwk,sync)
! Compute sync power for a complex, downsampled FT4 signal.
! 20 samples per symbol
include 'ft4_params.f90'
parameter(NP=NMAX/16)
complex cd0(0:NP-1)
complex csync(80)
complex csync2(80)
complex ctwk(80)
complex z1,z2,z3
logical first
integer icos4(0:3)
data icos4/0,1,3,2/
data first/.true./
save first,twopi,fs2,dt2,taus,baud,csync
p(z1)=real(z1)**2 + aimag(z1)**2 !Statement function for power
! Set some constants and compute the csync array.
if( first ) then
twopi=8.0*atan(1.0)
fs2=12000.0/NDOWN !Sample rate after downsampling
dt2=1/fs2 !Corresponding sample interval
taus=20*dt2 !Symbol duration
baud=1.0/taus !Keying rate
k=1
phi=0.0
do i=0,3
! dphi=(twopi/2.0)*(2*icos4(i)-3)*baud*dt2
dphi=twopi*icos4(i)*baud*dt2
do j=1,20
csync(k)=cmplx(cos(phi),sin(phi)) !Waveform for 7x7 Costas array
phi=mod(phi+dphi,twopi)
k=k+1
enddo
enddo
first=.false.
endif
sync=0
i1=i0 !three Costas arrays
i2=i0+36*20-1
i3=i0+72*20-1
csync2=csync
if(itwk.eq.1) csync2=ctwk*csync2 !Tweak the frequency
if(i1.ge.0 .and. i1+79.le.NP-1) z1=sum(cd0(i1:i1+79)*conjg(csync2))
if(i2.ge.0 .and. i2+79.le.NP-1) z2=sum(cd0(i2:i2+79)*conjg(csync2))
if(i3.ge.0 .and. i3+79.le.NP-1) z3=sum(cd0(i3:i3+79)*conjg(csync2))
sync = sync + p(z1) + p(z2) + p(z3)
return
end subroutine sync4d

145
lib/ft4/syncft4.f90 Normal file
View File

@ -0,0 +1,145 @@
subroutine syncft4(iwave,nfa,nfb,syncmin,nfqso,maxcand,s,candidate, &
ncand,sbase)
include 'ft4_params.f90'
! Search over +/- 2.5s relative to 0.5s TX start time.
parameter (JZ=20)
complex cx(0:NH1)
real s(NH1,NHSYM)
real savg(NH1)
real sbase(NH1)
real x(NFFT1)
real sync2d(NH1,-JZ:JZ)
real red(NH1)
real candidate0(3,maxcand)
real candidate(3,maxcand)
real dd(NMAX)
integer jpeak(NH1)
integer indx(NH1)
integer ii(1)
integer*2 iwave(NMAX)
integer icos4(0:3)
data icos4/0,1,3,2/ !Costas 4x4 tone pattern
equivalence (x,cx)
dd=iwave/1e3
! Compute symbol spectra, stepping by NSTEP steps.
savg=0.
tstep=NSTEP/12000.0
df=12000.0/NFFT1 !3.125 Hz
fac=1.0/300.0
do j=1,NHSYM
ia=(j-1)*NSTEP + 1
ib=ia+NSPS-1
x(1:NSPS)=fac*dd(ia:ib)
x(NSPS+1:)=0.
call four2a(x,NFFT1,1,-1,0) !r2c FFT
do i=1,NH1
s(i,j)=real(cx(i))**2 + aimag(cx(i))**2
enddo
savg=savg + s(1:NH1,j) !Average spectrum
enddo
call baseline(savg,nfa,nfb,sbase)
ia=max(1,nint(nfa/df))
ib=nint(nfb/df)
nssy=NSPS/NSTEP ! # steps per symbol
nfos=NFFT1/NSPS ! # frequency bin oversampling factor
jstrt=0.25/tstep
candidate0=0.
k=0
do i=ia,ib
do j=-JZ,+JZ
ta=0.
tb=0.
tc=0.
t0a=0.
t0b=0.
t0c=0.
do n=0,3
m=j+jstrt+nssy*n
if(m.ge.1.and.m.le.NHSYM) then
ta=ta + s(i+nfos*icos4(n),m)
t0a=t0a + sum(s(i:i+nfos*3:nfos,m))
endif
tb=tb + s(i+nfos*icos4(n),m+nssy*36)
t0b=t0b + sum(s(i:i+nfos*3:nfos,m+nssy*36))
if(m+nssy*72.le.NHSYM) then
tc=tc + s(i+nfos*icos4(n),m+nssy*72)
t0c=t0c + sum(s(i:i+nfos*3:nfos,m+nssy*72))
endif
enddo
t=ta+tb+tc
t0=t0a+t0b+t0c
t0=(t0-t)/3.0
sync_abc=t/t0
t=tb+tc
t0=t0b+t0c
t0=(t0-t)/3.0
sync_bc=t/t0
sync2d(i,j)=max(sync_abc,sync_bc)
enddo
enddo
red=0.
do i=ia,ib
ii=maxloc(sync2d(i,-JZ:JZ)) - 1 - JZ
j0=ii(1)
jpeak(i)=j0
red(i)=sync2d(i,j0)
enddo
iz=ib-ia+1
call indexx(red(ia:ib),iz,indx)
ibase=indx(nint(0.40*iz)) - 1 + ia
if(ibase.lt.1) ibase=1
if(ibase.gt.nh1) ibase=nh1
base=red(ibase)
red=red/base
do i=1,min(maxcand,iz)
n=ia + indx(iz+1-i) - 1
if(red(n).lt.syncmin.or.isnan(red(n)).or.k.eq.maxcand) exit
k=k+1
! candidate0(1,k)=n*df+37.5*1.5
candidate0(1,k)=n*df
candidate0(2,k)=(jpeak(n)-1)*tstep
candidate0(3,k)=red(n)
enddo
ncand=k
! Put nfqso at top of list, and save only the best of near-dupe freqs.
do i=1,ncand
if(abs(candidate0(1,i)-nfqso).lt.10.0) candidate0(1,i)=-candidate0(1,i)
if(i.ge.2) then
do j=1,i-1
fdiff=abs(candidate0(1,i))-abs(candidate0(1,j))
if(abs(fdiff).lt.4.0) then
if(candidate0(3,i).ge.candidate0(3,j)) candidate0(3,j)=0.
if(candidate0(3,i).lt.candidate0(3,j)) candidate0(3,i)=0.
endif
enddo
endif
enddo
fac=20.0/maxval(s)
s=fac*s
! Sort by sync
! call indexx(candidate0(3,1:ncand),ncand,indx)
! Sort by frequency
call indexx(candidate0(1,1:ncand),ncand,indx)
k=1
! do i=ncand,1,-1
do i=1,ncand
j=indx(i)
! if( candidate0(3,j) .ge. syncmin .and. candidate0(2,j).ge.-1.5 ) then
if( candidate0(3,j) .ge. syncmin ) then
candidate(2:3,k)=candidate0(2:3,j)
candidate(1,k)=abs(candidate0(1,j))
k=k+1
endif
enddo
ncand=k-1
return
end subroutine syncft4