mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-14 08:01:49 -05:00
115 lines
3.7 KiB
Fortran
115 lines
3.7 KiB
Fortran
program ft4slowsim
|
|
|
|
! Generate simulated signals for experimental slow FT4 mode
|
|
|
|
use wavhdr
|
|
use packjt77
|
|
include 'wspr4_params.f90' !Set various constants
|
|
type(hdr) h !Header for .wav file
|
|
character arg*12,fname*17
|
|
character msg37*37,msgsent37*37
|
|
character c77*77
|
|
complex c0(0:NMAX-1)
|
|
complex c(0:NMAX-1)
|
|
real wave(NMAX)
|
|
integer itone(NN)
|
|
integer*1 msgbits(101)
|
|
integer*2 iwave(NMAX) !Generated full-length waveform
|
|
|
|
! Get command-line argument(s)
|
|
nargs=iargc()
|
|
if(nargs.ne.7) then
|
|
print*,'Usage: ft4slowsim "message" f0 DT fdop del nfiles snr'
|
|
print*,'Examples: ft4slowsim "K1JT K9AN EN50" 1500 0.0 0.1 1.0 10 -15'
|
|
go to 999
|
|
endif
|
|
call getarg(1,msg37) !Message to be transmitted
|
|
call getarg(2,arg)
|
|
read(arg,*) f0 !Frequency (only used for single-signal)
|
|
call getarg(3,arg)
|
|
read(arg,*) xdt !Time offset from nominal (s)
|
|
call getarg(4,arg)
|
|
read(arg,*) fspread !Watterson frequency spread (Hz)
|
|
call getarg(5,arg)
|
|
read(arg,*) delay !Watterson delay (ms)
|
|
call getarg(6,arg)
|
|
read(arg,*) nfiles !Number of files
|
|
call getarg(7,arg)
|
|
read(arg,*) snrdb !SNR_2500
|
|
|
|
nfiles=abs(nfiles)
|
|
twopi=8.0*atan(1.0)
|
|
fs=12000.0 !Sample rate (Hz)
|
|
dt=1.0/fs !Sample interval (s)
|
|
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=NZ2*dt !Transmission length (s)
|
|
|
|
bandwidth_ratio=2500.0/(fs/2.0)
|
|
sig=sqrt(2*bandwidth_ratio) * 10.0**(0.05*snrdb)
|
|
if(snrdb.gt.90.0) sig=1.0
|
|
|
|
call genft4slow(msg37,0,msgsent37,msgbits,itone)
|
|
write(*,*)
|
|
write(*,'(a9,a37,3x,a7,i1,a1,i1)') 'Message: ',msgsent37,'i3.n3: ',i3,'.',n3
|
|
write(*,1000) f0,xdt,txt,snrdb
|
|
1000 format('f0:',f9.3,' DT:',f6.2,' TxT:',f6.1,' SNR:',f6.1)
|
|
write(*,*)
|
|
if(i3.eq.1) then
|
|
write(*,*) ' mycall hiscall hisgrid'
|
|
write(*,'(28i1,1x,i1,1x,28i1,1x,i1,1x,i1,1x,15i1,1x,3i1)') msgbits(1:77)
|
|
else
|
|
write(*,'(a14)') 'Message bits: '
|
|
write(*,'(50i1,1x,24i1)') msgbits
|
|
endif
|
|
write(*,*)
|
|
write(*,'(a17)') 'Channel symbols: '
|
|
write(*,'(10i1)') itone
|
|
write(*,*)
|
|
|
|
call sgran()
|
|
|
|
fsample=12000.0
|
|
icmplx=1
|
|
call gen_wspr4wave(itone,NN,NSPS,fsample,f0,c0,wave,icmplx,NMAX)
|
|
k=nint((xdt+1.0)/dt)-NSPS
|
|
c0=cshift(c0,-k)
|
|
if(k.gt.0) c0(0:k-1)=0.0
|
|
if(k.lt.0) c0(NMAX+k:NMAX-1)=0.0
|
|
|
|
do ifile=1,nfiles
|
|
c=c0
|
|
if(fspread.ne.0.0 .or. delay.ne.0.0) call watterson(c,NMAX,NZ,fs,delay,fspread)
|
|
c=sig*c
|
|
wave=real(c)
|
|
peak=maxval(abs(wave))
|
|
nslots=1
|
|
if(snrdb.lt.90) then
|
|
do i=1,NMAX !Add gaussian noise at specified SNR
|
|
xnoise=gran()
|
|
wave(i)=wave(i) + xnoise
|
|
enddo
|
|
endif
|
|
gain=100.0
|
|
if(snrdb.lt.90.0) then
|
|
wave=gain*wave
|
|
else
|
|
datpk=maxval(abs(wave))
|
|
fac=32766.9/datpk
|
|
wave=fac*wave
|
|
endif
|
|
if(any(abs(wave).gt.32767.0)) print*,"Warning - data will be clipped."
|
|
iwave=nint(wave)
|
|
h=default_header(12000,NMAX)
|
|
write(fname,1102) ifile
|
|
1102 format('000000_',i6.6,'.wav')
|
|
open(10,file=fname,status='unknown',access='stream')
|
|
write(10) h,iwave !Save to *.wav file
|
|
close(10)
|
|
write(*,1110) ifile,xdt,f0,snrdb,fname
|
|
1110 format(i4,f7.2,f8.2,f7.1,2x,a17)
|
|
enddo
|
|
|
|
999 end program ft4slowsim
|