WSJT-X/lib/ft4/ft4_params.f90

17 lines
946 B
Fortran

! FT4
! LDPC(174,91) code, four 4x4 Costas arrays for Sync
parameter (KK=91) !Information bits (77 + CRC14)
parameter (ND=87) !Data symbols
parameter (NS=16) !Sync symbols
parameter (NN=NS+ND) !Sync and data symbols (103)
parameter (NN2=NS+ND+2) !Total channel symbols (105)
parameter (NSPS=512) !Samples per symbol at 12000 S/s
parameter (NZ=NSPS*NN) !Sync and Data samples (52736)
parameter (NZ2=NSPS*NN2) !Total samples in shaped waveform (53760)
parameter (NMAX=5*12000) !Samples in iwave (60,000)
parameter (NFFT1=2048, 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