55 lines
1.6 KiB
Plaintext
55 lines
1.6 KiB
Plaintext
|
program ft8d
|
||
|
|
|
||
|
|
! Decode FT8 data read from *.wav files.
|
||
|
|
|
||
|
|
! FT8 is a potential mode intended for use at 6m (and maybe HF). It uses an
|
||
|
|
! LDPC (174,87) code, 8-FSK modulation, and 15 second T/R sequences. Otherwise
|
||
|
|
! should behave like JT65 and JT9 as used on HF bands, except that QSOs are
|
||
|
|
! 4 x faster.
|
||
|
|
|
||
|
|
! Reception and Demodulation algorithm:
|
||
|
|
! ... tbd ...
|
||
|
|
|
||
|
|
include 'ft8_params.f90'
|
||
|
|
character*12 arg
|
||
|
|
character infile*80,datetime*13
|
||
|
|
real s(NH1,NHSYM)
|
||
|
|
real candidate(3,100)
|
||
|
|
integer ihdr(11)
|
||
|
|
integer*2 iwave(NMAX) !Generated full-length waveform
|
||
|
|
|
||
|
|
nargs=iargc()
|
||
|
|
if(nargs.lt.3) then
|
||
|
|
print*,'Usage: ft8d MaxIt Norder file1 [file2 ...]'
|
||
|
|
print*,'Example ft8d 40 2 *.wav'
|
||
|
|
go to 999
|
||
|
|
endif
|
||
|
|
call getarg(1,arg)
|
||
|
|
read(arg,*) max_iterations
|
||
|
|
call getarg(2,arg)
|
||
|
|
read(arg,*) norder
|
||
|
|
nfiles=nargs-2
|
||
|
|
|
||
|
|
twopi=8.0*atan(1.0)
|
||
|
|
fs=12000.0 !Sample rate
|
||
|
|
dt=1.0/fs !Sample interval (s)
|
||
|
|
tt=NSPS*dt !Duration of "itone" symbols (s)
|
||
|
|
ts=2*NSPS*dt !Duration of OQPSK symbols (s)
|
||
|
|
baud=1.0/tt !Keying rate (baud)
|
||
|
|
txt=NZ*dt !Transmission length (s)
|
||
|
|
|
||
|
|
do ifile=1,nfiles
|
||
|
|
call getarg(ifile+2,infile)
|
||
|
|
open(10,file=infile,status='old',access='stream')
|
||
|
|
read(10,end=999) ihdr,iwave
|
||
|
|
close(10)
|
||
|
|
j2=index(infile,'.wav')
|
||
|
|
read(infile(j2-6:j2-1),*) nutc
|
||
|
|
datetime=infile(j2-13:j2-1)
|
||
|
|
call sync8(iwave,s,candidate,ncand)
|
||
|
|
call ft8b(datetime,s,candidate,ncand)
|
||
|
|
enddo ! ifile loop
|
||
|
|
|
||
|
|
999 end program ft8d
|
||
|
|
|