mirror of https://github.com/saitohirga/WSJT-X.git
45 lines
995 B
Fortran
45 lines
995 B
Fortran
subroutine wspr_fsk8_wav(baud,xdt,f0,itone,snrdb,iwave)
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! Generate iwave() from itone().
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include 'wspr_fsk8_params.f90'
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integer itone(NN)
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integer*2 iwave(NMAX)
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real*8 twopi,dt,dphi,phi
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real dat(NMAX)
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twopi=8.d0*atan(1.d0)
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dt=1.d0/12000.d0
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dat=0.
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if(snrdb.lt.90) then
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do i=1,NMAX
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dat(i)=gran() !Generate gaussian noise, rms = 1.0
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enddo
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bandwidth_ratio=2500.0/6000.0
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sig=sqrt(2*bandwidth_ratio)*10.0**(0.05*snrdb)
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else
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sig=1.0
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endif
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phi=0.d0
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k=nint((xdt+1.0)/dt)
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do j=1,NN
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dphi=twopi*(f0+ itone(j)*baud)*dt
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if(k.eq.0) phi=-dphi
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do i=1,NSPS0
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k=k+1
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phi=phi+dphi
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if(phi.gt.twopi) phi=phi-twopi
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xphi=phi
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if(k.gt.0 .and. k.le.NMAX) dat(k)=dat(k) + sig*sin(xphi)
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enddo
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enddo
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fac=32767.0
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rms=100.0
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if(snrdb.ge.90.0) iwave=nint(fac*dat)
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if(snrdb.lt.90.0) iwave=nint(rms*dat)
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return
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end subroutine wspr_fsk8_wav
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