program jt65sim
! Generate simulated JT65 data for testing WSJT-X
use wavhdr
use packjt
use options
parameter (NMAX=54*12000) ! = 648,000 @12kHz
parameter (NFFT=10*65536,NH=NFFT/2)
type(hdr) h !Header for .wav file
integer*2 iwave(NMAX) !Generated waveform
integer*4 itone(126) !Channel symbols (values 0-65)
integer dgen(12) !Twelve 6-bit data symbols
integer sent(63) !RS(63,12) codeword
real*4 xnoise(NMAX) !Generated random noise
real*4 dat(NMAX) !Generated real data
complex cdat(NMAX) !Generated complex waveform
complex cspread(0:NFFT-1) !Complex amplitude for Rayleigh fading
complex z
real*8 f0,dt,twopi,phi,dphi,baud,fsample,freq,sps
character msg*22,fname*11,csubmode*1,c,optarg*500,numbuf*32
! character call1*5,call2*5
logical :: display_help=.false.,seed_prngs=.true.
type (option) :: long_options(13) = [ &
option ('help',.false.,'h','Display this help message',''), &
option ('sub-mode',.true.,'m','sub mode, default MODE=A','MODE'), &
option ('num-sigs',.true.,'n','number of signals per file, default SIGNALS=10','SIGNALS'), &
option ('f0',.true.,'F','base frequency offset, default F0=1500.0','F0'), &
option ('doppler-spread',.true.,'d','Doppler spread, default SPREAD=0.0','SPREAD'), &
option ('drift per min',.true.,'D','Frequency drift (Hz/min), default DRIFT=0.0','DRIFT'), &
option ('time-offset',.true.,'t','Time delta, default SECONDS=0.0','SECONDS'), &
option ('num-files',.true.,'f','Number of files to generate, default FILES=1','FILES'), &
option ('no-prng-seed',.false.,'p','Do not seed PRNGs (use for reproducible tests)',''), &
option ('strength',.true.,'s','S/N in dB (2500Hz reference b/w), default SNR=0','SNR'), &
option ('11025',.false.,'S','Generate at 11025Hz sample rate, default 12000Hz',''), &
option ('gain-offset',.true.,'G','Gain offset in dB, default GAIN=0dB','GAIN'), &
option ('message',.true.,'M','Message text','Message') ]
integer nprc(126) !Sync pattern
data nprc/1,0,0,1,1,0,0,0,1,1,1,1,1,1,0,1,0,1,0,0, &
0,1,0,1,1,0,0,1,0,0,0,1,1,1,0,0,1,1,1,1, &
0,1,1,0,1,1,1,1,0,0,0,1,1,0,1,0,1,0,1,1, &
0,0,1,1,0,1,0,1,0,1,0,0,1,0,0,0,0,0,0,1, &
1,0,0,0,0,0,0,0,1,1,0,1,0,0,1,0,1,1,0,1, &
0,1,0,1,0,0,1,1,0,0,1,0,0,1,0,0,0,0,1,1, &
1,1,1,1,1,1/
! Default parameters:
csubmode='A'
mode65=1
nsigs=10
bf0=1500.
fspread=0.
drift=0.
xdt=0.
snrdb=0.
nfiles=1
nsample_rate=12000
gain_offset=0.
msg="K1ABC W9XYZ EN37"
do
call getopt('hm:n:F:d:D:t:f:ps:SG:M:',long_options,c,optarg,narglen,nstat,noffset,nremain,.true.)
if( nstat .ne. 0 ) then
exit
end if
select case (c)
case ('h')
display_help = .true.
case ('m')
read (optarg(:narglen), *) csubmode
if(csubmode.eq.'A') mode65=1
if(csubmode.eq.'B') mode65=2
if(csubmode.eq.'C') mode65=4
case ('n')
read (optarg(:narglen), *,err=10) nsigs
case ('F')
read (optarg(:narglen), *,err=10) bf0
case ('d')
read (optarg(:narglen), *,err=10) fspread
case ('D')
read (optarg(:narglen), *,err=10) drift
case ('t')
read (optarg(:narglen), *) numbuf
if (numbuf(1:1) == '\') then !'\'
read (numbuf(2:), *,err=10) xdt
else
read (numbuf, *,err=10) xdt
end if
case ('f')
read (optarg(:narglen), *,err=10) nfiles
case ('p')
seed_prngs=.false.
case ('s')
read (optarg(:narglen), *) numbuf
if (numbuf(1:1) == '\') then !'\'
read (numbuf(2:), *,err=10) snrdb
else
read (numbuf, *,err=10) snrdb
end if
case ('S')
nsample_rate=11025
case ('G')
read (optarg(:narglen), *) numbuf
if (numbuf(1:1) == '\') then !'\'
read (numbuf(2:), *, err=10) gain_offset
else
read (numbuf, *, err=10) gain_offset
end if
case ('M')
read (optarg(:narglen), '(A)',err=10) msg
end select
cycle
10 display_help=.true.
print *, 'Optional argument format error for option -', c
end do
if(display_help .or. nstat.lt.0 .or. nremain.ge.1) then
print *, ''
print *, 'Usage: jt65sim [OPTIONS]'
print *, ''
print *, ' Generate one or more simulated JT65 signals in .WAV file(s)'
print *, ''
print *, 'Example: jt65sim -m B -n 10 -d 0.2 -s \\-24.5 -t 0.0 -f 4'
print *, ''
print *, 'OPTIONS: NB Use \ (\\ on *nix shells) to escape -ve arguments'
print *, ''
do i = 1, size (long_options)
call long_options(i) % print (6)
end do
go to 999
endif
if (seed_prngs) then
call init_random_seed() ! seed Fortran RANDOM_NUMBER generator
call sgran() ! see C rand generator (used in gran)
end if
rms=100. * 10. ** (gain_offset / 20.)
fsample=nsample_rate !Sample rate (Hz)
dt=1.d0/fsample !Sample interval (s)
twopi=8.d0*atan(1.d0)
npts=54*nsample_rate !Total samples in .wav file
baud=11025.d0/4096.d0 !Keying rate
sps=real(nsample_rate)/baud !Samples per symbol, at fsample=NSAMPLE_RATE Hz
nsym=126 !Number of channel symbols
h=default_header(nsample_rate,npts)
dfsig=2000.0/nsigs !Freq spacing between sigs in file (Hz)
do ifile=1,nfiles !Loop over requested number of files
write(fname,1002) ifile !Output filename
1002 format('000000_',i4.4)
open(10,file=fname//'.wav',access='stream',status='unknown')
xnoise=0.
cdat=0.
if(snrdb.lt.90) then
do i=1,npts
xnoise(i)=gran() !Generate gaussian noise
enddo
endif
do isig=1,nsigs !Generate requested number of sigs
if(mod(nsigs,2).eq.0) f0=bf0 + dfsig*(isig-0.5-nsigs/2)
if(mod(nsigs,2).eq.1) f0=bf0 + dfsig*(isig-(nsigs+1)/2)
xsnr=snrdb
if(snrdb.eq.0.0) xsnr=-19 - isig
if(csubmode.eq.'B' .and. snrdb.eq.0.0) xsnr=-21 - isig
if(csubmode.eq.'C' .and. snrdb.eq.0.0) xsnr=-21 - isig
call packmsg(msg,dgen,itype) !Pack message into 12 six-bit bytes
call rs_encode(dgen,sent) !Encode using RS(63,12)
call interleave63(sent,1) !Interleave channel symbols
call graycode65(sent,63,1) !Apply Gray code
nprc_test=0
i1=len(trim(msg))
if(i1.gt.10) then
if(msg(i1-3:i1).eq.' OOO') nprc_test=1
endif
k=0
do j=1,nsym !Insert sync and data into itone()
if(nprc(j).eq.nprc_test) then
k=k+1
itone(j)=sent(k)+2
else
itone(j)=0
endif
enddo
if(len(trim(msg)).eq.2.or.len(trim(msg)).eq.3) then
nshorthand=0
if(msg(1:2).eq.'RO') nshorthand=2
if(msg(1:3).eq.'RRR') nshorthand=3
if(msg(1:2).eq.'73') nshorthand=4
if(nshorthand.gt.0) then
ntoggle=0
do i=1,nsym,4
itone(i)=ntoggle*10*nshorthand
if(i+1.le.126) itone(i+1)=ntoggle*10*nshorthand
if(i+2.le.126) itone(i+2)=ntoggle*10*nshorthand
if(i+3.le.126) itone(i+3)=ntoggle*10*nshorthand
ntoggle=mod(ntoggle+1,2)
enddo
endif
endif
bandwidth_ratio=2500.0/(fsample/2.0)
sig=sqrt(2*bandwidth_ratio)*10.0**(0.05*xsnr)
if(xsnr.gt.90.0) sig=1.0
write(*,1020) ifile,isig,f0,csubmode,xsnr,xdt,fspread,msg
1020 format(i4,i4,f10.3,2x,a1,2x,f5.1,f6.2,f5.1,1x,a22)
phi=0.d0
dphi=0.d0
k=nsample_rate + xdt*nsample_rate !Start audio at t = xdt + 1.0 s
isym0=-99
do i=1,npts !Add this signal into cdat()
isym=floor(i/sps)+1
if(isym.gt.nsym) exit
freq=f0 + (drift/60.0)*(i-npts/2)*dt + itone(isym)*baud*mode65
dphi=twopi*freq*dt
phi=phi + dphi
if(phi.gt.twopi) phi=phi-twopi
xphi=phi
z=cmplx(cos(xphi),sin(xphi))
k=k+1
if(k.ge.1) cdat(k)=cdat(k) + sig*z
enddo
enddo
if(fspread.ne.0) then !Apply specified Doppler spread
df=real(nsample_rate)/nfft
twopi=8*atan(1.0)
cspread(0)=1.0
cspread(NH)=0.
! The following options were added 3/15/2016 to make the half-power tone
! widths equal to the requested Doppler spread. (Previously we effectively
! used b=1.0 and Gaussian shape, which made the tones 1.665 times wider.)
! b=2.0*sqrt(log(2.0)) !Gaussian (before 3/15/2016)
! b=2.0 !Lorenzian 3/15 - 3/27
b=6.0 !Lorenzian 3/28 onward
do i=1,NH
f=i*df
x=b*f/fspread
z=0.
a=0.
if(x.lt.3.0) then !Cutoff beyond x=3
! a=sqrt(exp(-x*x)) !Gaussian
a=sqrt(1.111/(1.0+x*x)-0.1) !Lorentzian
call random_number(r1)
phi1=twopi*r1
z=a*cmplx(cos(phi1),sin(phi1))
endif
cspread(i)=z
z=0.
if(x.lt.50.0) then
call random_number(r2)
phi2=twopi*r2
z=a*cmplx(cos(phi2),sin(phi2))
endif
cspread(NFFT-i)=z
enddo
do i=0,NFFT-1
f=i*df
if(i.gt.NH) f=(i-nfft)*df
s=real(cspread(i))**2 + aimag(cspread(i))**2
! write(13,3000) i,f,s,cspread(i)
!3000 format(i5,f10.3,3f12.6)
enddo
! s=real(cspread(0))**2 + aimag(cspread(0))**2
! write(13,3000) 1024,0.0,s,cspread(0)
call four2a(cspread,NFFT,1,1,1) !Transform to time domain
sum=0.
do i=0,NFFT-1
p=real(cspread(i))**2 + aimag(cspread(i))**2
sum=sum+p
enddo
avep=sum/NFFT
fac=sqrt(1.0/avep)
cspread=fac*cspread !Normalize to constant avg power
cdat(1:npts)=cspread(1:npts)*cdat(1:npts) !Apply Rayleigh fading
! do i=0,NFFT-1
! p=real(cspread(i))**2 + aimag(cspread(i))**2
! write(14,3010) i,p,cspread(i)
!3010 format(i8,3f12.6)
! enddo
endif
dat(1:npts)=aimag(cdat(1:npts)) + xnoise(1:npts) !Add the generated noise
if(snrdb.lt.90.0) then
dat(1:npts)=rms*dat(1:npts)
else
datpk=maxval(abs(dat(1:npts)))
fac=32766.9/datpk
dat(1:npts)=fac*dat(1:npts)
endif
if(any(abs(dat(1:npts)).gt.32767.0)) print*,"Warning - data will be clipped."
iwave(1:npts)=nint(dat(1:npts))
write(10) h,iwave(1:npts) !Save the .wav file
close(10)
enddo
999 end program jt65sim