WSJT-X/lib/fsk4hf/wsprcpm_wav.f90
Steven Franke 67a41a9f1d Add some simulation tools for binary cpm with sequence detection.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@8586 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2018-03-22 14:21:39 +00:00

58 lines
1.3 KiB
Fortran

subroutine wsprcpm_wav(baud,xdt,h1,h2,f0,itone,snrdb,iwave)
! Generate iwave() from itone().
include 'wsprcpm_params.f90'
parameter (NMAX=120*12000)
integer itone(NN)
integer*2 iwave(NMAX)
real*8 twopi,dt,dphi0,dphi1,dphi,phi
real dat(NMAX)
twopi=8.d0*atan(1.d0)
dt=1.d0/12000.d0
dat=0.
if(snrdb.lt.90) then
do i=1,NMAX
dat(i)=gran() !Generate gaussian noise
enddo
bandwidth_ratio=2500.0/6000.0
sig=sqrt(2*bandwidth_ratio)*10.0**(0.05*snrdb)
else
sig=1.0
endif
dphi01=twopi*(f0-(h1/2.0d0)*baud)*dt
dphi11=twopi*(f0+(h1/2.0d0)*baud)*dt
dphi02=twopi*(f0-(h2/2.0d0)*baud)*dt
dphi12=twopi*(f0+(h2/2.0d0)*baud)*dt
phi=0.d0
k=nint(xdt/dt)
do j=1,NN
if( mod(j,2).eq.0 ) then
dphi0=dphi01
dphi1=dphi11
else
dphi0=dphi02
dphi1=dphi12
endif
dphi=dphi0
if(itone(j).eq.1) dphi=dphi1
if(k.eq.0) phi=-dphi
do i=1,NSPS0
k=k+1
phi=phi+dphi
if(phi.gt.twopi) phi=phi-twopi
xphi=phi
if(k.gt.0 .and. k.le.NMAX) dat(k)=dat(k) + sig*sin(xphi)
enddo
enddo
fac=32767.0
rms=100.0
if(snrdb.ge.90.0) iwave=nint(fac*dat)
if(snrdb.lt.90.0) iwave=nint(rms*dat)
return
end subroutine wsprcpm_wav