37 lines
946 B
Fortran
37 lines
946 B
Fortran
|
subroutine genfsk4(id,f00,nts,c)
|
||
|
|
|
||
|
|
parameter (ND=60) !Data symbols: LDPC (120,60), r=1/2
|
||
|
|
parameter (NN=ND) !Total symbols (60)
|
||
|
|
parameter (NSPS=57600) !Samples per symbol at 12000 sps
|
||
|
|
parameter (NZ=NSPS*NN) !Samples in waveform (3456000)
|
||
|
|
parameter (NFFT=NZ) !Full length FFT
|
||
|
|
|
||
|
|
complex c(0:NFFT-1) !Complex waveform
|
||
|
|
real*8 twopi,dt,fs,baud,f0,dphi,phi
|
||
|
|
integer id(NN) !Encoded 2-bit data (values 0-3)
|
||
|
|
|
||
|
|
f0=f00
|
||
|
|
twopi=8.d0*atan(1.d0)
|
||
|
|
fs=12000.d0
|
||
|
|
dt=1.0/fs
|
||
|
|
baud=1.d0/(NSPS*dt)
|
||
|
|
|
||
|
|
! Generate the 4-FSK waveform
|
||
|
|
x=0.
|
||
|
|
c=0.
|
||
|
|
phi=0.d0
|
||
|
|
k=-1
|
||
|
|
do j=1,NN
|
||
|
|
dphi=twopi*(f0 + nts*id(j)*baud)*dt
|
||
|
|
do i=1,NSPS
|
||
|
|
k=k+1
|
||
|
|
phi=phi+dphi
|
||
|
|
if(phi.gt.twopi) phi=phi-twopi
|
||
|
|
xphi=phi
|
||
|
|
c(k)=cmplx(cos(xphi),sin(xphi))
|
||
|
|
enddo
|
||
|
|
enddo
|
||
|
|
|
||
|
|
return
|
||
|
|
end subroutine genfsk4
|