wspr5d_exp now tries to detect sequences of 3, 6, and 9 bits.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7700 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Steven Franke 2017-06-02 13:58:32 +00:00
parent f8a673077b
commit a92e7508b9
7 changed files with 363 additions and 137 deletions

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@ -647,9 +647,14 @@ do iter=0,maxiterations
enddo
!write(*,*) 'number of unsatisfied parity checks ',ncheck
if( ncheck .eq. 0 ) then ! we have a codeword - reorder the columns and return it
niterations=iter
! niterations=iter
codeword=cw(colorder+1)
decoded=codeword(M+1:N)
nerr=0
do i=1,N
if( (2*cw(i)-1)*llr(i) .lt. 0.0 ) nerr=nerr+1
enddo
niterations=nerr
return
endif

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@ -20,16 +20,8 @@ subroutine getfc2w(c,csync,npeaks,fs,fc1,fpks)
ia=nint(0.75*baud/df)
cs(ia:NZ-1-ia)=0. !Save only freqs around fc1
! do i=1,NZ/2
! filt=1/(1+((i*df)**2/(0.50*baud)**2)**8)
! cs(i)=cs(i)*filt
! cs(NZ+1-i)=cs(NZ+1-i)*filt
! enddo
call four2a(cs,NZ,1,1,1) !Back to time domain
cs=cs/NZ
!do i=0,NZ-1
!write(51,*) i,real(cs(i)),imag(cs(i))
!enddo
cs=cs*cs !Square the data
call four2a(cs,NZ,1,-1,1) !Compute squared spectrum
@ -37,7 +29,6 @@ subroutine getfc2w(c,csync,npeaks,fs,fc1,fpks)
pmax=0.
fc2=0.
ja=nint(0.3*baud/df)
! ja=nint(0.5*baud/df)
k=1
do j=-ja,ja
f2=j*df

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@ -80,9 +80,6 @@ do id=1,K ! diagonal element indices
enddo
g2=transpose(genmrb)
!do i=1,N
! g2(i,1:K)=genmrb(1:K,i)
!enddo
! The hard decisions for the K MRB bits define the order 0 message, m0.
! Encode m0 using the modified generator matrix to find the "order 0" codeword.
@ -140,8 +137,13 @@ enddo
! re-order the codeword to place message bits at the end
cw(indices)=cw
hdec(indices)=hdec
decoded=cw(M+1:N)
niterations=1
nerr=0
do i=1,N
if( hdec(i) .ne. cw(i) ) nerr=nerr+1
enddo
niterations=nerr
return
end subroutine osd300

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@ -122,10 +122,10 @@ program wspr5d
go to 999
endif
close(10)
fa=102.0
fa=100.0
fb=150.0
call getfc1w(c,fs,fa,fb,fc1,xsnr) !First approx for freq
npeaks=20
npeaks=20
call getfc2w(c,csync,npeaks,fs,fc1,fpks) !Refined freq
a(1)=-fc1
@ -152,6 +152,7 @@ npeaks=20
ibb=NZ-1-j
endif
z=sum(c(ia:ib)*conjg(csync(iaa:ibb)))
write(51,*) j/fs,real(z),imag(z)
if(abs(z).gt.amax) then
amax=abs(z)
jpk=j

View File

@ -7,18 +7,33 @@ program wspr5d
!
! Still to do: find and decode more than one signal in the specified passband.
include 'wsprlf_params.f90'
! include 'wsprlf_params.f90'
parameter (NDOWN=30)
parameter (KK=60)
parameter (ND=300)
parameter (NS=109)
parameter (NR=3)
parameter (NN=NR+NS+ND)
parameter (NSPS0=8640)
parameter (NSPS=16)
parameter (N2=2*NSPS)
parameter (NZ=NSPS*NN)
parameter (NZ400=288*NN)
parameter (NMAX=300*12000)
character arg*8,message*22,cbits*50,infile*80,fname*16,datetime*11
character*120 data_dir
complex csync(0:NZ-1) !Sync symbols only, from cbb
complex c400(0:NZ400-1) !Complex waveform
complex c(0:NZ-1) !Complex waveform
complex cd(0:412*16-1) !Complex waveform
complex ca(0:412*16-1) !Complex waveform
complex cd(0:NZ-1) !Complex waveform
complex ca(0:NZ-1) !Complex waveform
complex zz
real*8 fMHz
real rxdata(ND),llr(ND) !Soft symbols
real pp(32) !Shaped pulse for OQPSK
real ps(0:7),sbits(412)
real sbits(412),softbits(9)
real fpks(20)
integer id(NS+ND) !NRZ values (+/-1) for Sync and Data
integer isync(48) !Long sync vector
@ -28,7 +43,7 @@ program wspr5d
integer*2 iwave(NMAX) !Generated full-length waveform
integer*1 idat(7)
integer*1 decoded(KK),apmask(ND),cw(ND)
integer*1 hbits(412),ebits(411),bits(5)
integer*1 hbits(412),bits(13)
data ib13/1,1,1,1,1,-1,-1,1,1,-1,1,-1,1/
nargs=iargc()
@ -98,117 +113,151 @@ program wspr5d
j1=index(infile,'.c5')
j2=index(infile,'.wav')
if(j1.gt.0) then
read(10,end=999) fname,ntrmin,fMHz,c
read(10,end=999) fname,ntrmin,fMHz,c400
read(fname(8:11),*) nutc
write(datetime,'(i11)') nutc
else if(j2.gt.0) then
read(10,end=999) ihdr,iwave
read(infile(j2-4:j2-1),*) nutc
datetime=infile(j2-11:j2-1)
call wspr5_downsample(iwave,c)
call wspr5_downsample(iwave,c400)
else
print*,'Wrong file format?'
go to 999
endif
close(10)
fa=100.0
fb=170.0
call getfc1w(c,fs,fa,fb,fc1,xsnr) !First approx for freq
! call getfc2w(c,csync,fs,fc1,fc2,fc3) !Refined freq
fb=150.0
fs400=400.0
call getfc1(c400,fs400,fa,fb,fc1,xsnr) !First approx for freq
!write(*,*) datetime,'initial guess ',fc1
npeaks=5
call getfc2w(c,csync,npeaks,fs,fc1,fpks) !Refined freq
call getfc2(c400,npeaks,fs400,fc1,fpks) !Refined freq
do idf=1,npeaks ! consider the top npeak peaks
fc2=fpks(idf)
!write(*,*) 'peak ',idf,fc1+fc2,fc2
call downsample(c400,fc1+fc2,cd)
s2=sum(cd*conjg(cd))/(16*412)
cd=cd/sqrt(s2)
do is=0,11 ! search over plus/minus 0.25 seconds for now
idt=is/2
if( mod(is,2).eq. 1 ) idt=-(is+1)/2
xdt=real(22+idt)/22.222 - 1.0
ca=cshift(cd,22+idt)
do iseq=1,3 ! try sequence estimation lengths of 3, 6, and 9 bits.
k=1-2*iseq
nseq=iseq*3
do i=1,408,iseq*4
k=k+iseq*2
j=(i+1)*16
call mskseqdet(nseq,ca(j),pp,id(k),softbits,1,phase)
hbits(i:i+iseq*4)=bits
sbits(i:i+iseq*4)=bits
!write(*,*) fc1+fc2
do ipks=1,npeaks
call downsample(c,fc1+fpks(ipks),cd)
sbits(i+1)=softbits(1)
sbits(i+2)=softbits(2)
if( id(k+1) .ne. 0 ) sbits(i+2)=id(k+1)*25
sbits(i+3)=softbits(3)
do ncoh=1,1,-1
do is=0,9
idt=is/2
if( mod(is,2).eq. 1 ) idt=-is/2
xdt=idt/22.222
k=-1
ca=cshift(cd,22+idt)
do i=1,408,4
k=k+2
j=(i+1)*16
call mskseqdet(ca(j),pp,id(k),bits,ps,ncoh)
r1=max(ps(1),ps(3),ps(5),ps(7))-max(ps(0),ps(2),ps(4),ps(6))
r2=max(ps(2),ps(3),ps(6),ps(7))-max(ps(0),ps(1),ps(4),ps(5))
r4=max(ps(4),ps(5),ps(6),ps(7))-max(ps(0),ps(1),ps(2),ps(3))
hbits(i:i+4)=bits
sbits(i:i+4)=bits
sbits(i+1)=r4
sbits(i+2)=r2
if( id(k+1) .ne. 0 ) sbits(i+2)=id(k+1)*25
sbits(i+3)=r1
if( iseq .ge. 2 ) then
sbits(i+5)=softbits(4)
sbits(i+6)=softbits(5)
if( id(k+3) .ne. 0 ) sbits(i+6)=id(k+3)*25
sbits(i+7)=softbits(6)
if( iseq .eq. 3 ) then
sbits(i+9)=softbits(7)
sbits(i+10)=softbits(8)
if( id(k+5) .ne. 0 ) sbits(i+10)=id(k+5)*25
sbits(i+11)=softbits(9)
endif
endif
enddo
j=1
do i=1,205
if( abs(id(i)) .ne. 2 ) then
rxdata(j)=sbits(2*i-1)
j=j+1
endif
enddo
do i=1,204
rxdata(j)=sbits(2*i)
j=j+1
enddo
rxav=sum(rxdata)/ND
rx2av=sum(rxdata*rxdata)/ND
rxsig=sqrt(rx2av-rxav*rxav)
rxdata=rxdata/rxsig
! sigma=0.84
sigma=1.20
llr=2*rxdata/(sigma*sigma)
apmask=0
max_iterations=40
ifer=0
nbadcrc=0
call bpdecode300(llr,apmask,max_iterations,decoded,niterations,cw)
! niterations will be equal to the Hamming distance between hard received word and the codeword
if(niterations.lt.0) call osd300(llr,3,decoded,niterations,cw)
if(niterations.ge.0) call chkcrc10(decoded,nbadcrc)
if(niterations.lt.0 .or. nbadcrc.ne.0) ifer=1
if( ifer.eq.0 ) then
write(cbits,1200) decoded(1:50)
1200 format(50i1)
read(cbits,1202) idat
1202 format(6b8,b2)
idat(7)=ishft(idat(7),6)
call wqdecode(idat,message,itype)
nsnr=nint(xsnr)
freq=fMHz + 1.d-6*(fc1+fc2)
nfdot=0
write(13,1210) datetime,0,nsnr,xdt,freq,message,nfdot
1210 format(a11,2i4,f6.2,f12.7,2x,a22,i3)
write(*,1212) datetime(8:11),nsnr,xdt,freq,nfdot,message,'*',idf,nseq,is,niterations
1212 format(a4,i4,f5.1,f11.6,i3,2x,a22,a1,i3,i3,i3,i4)
goto 888
endif
enddo !iseq
enddo
j=1
do i=1,205
if( abs(id(i)) .ne. 2 ) then
rxdata(j)=sbits(2*i-1)
j=j+1
endif
enddo
do i=1,204
rxdata(j)=sbits(2*i)
j=j+1
enddo
rxav=sum(rxdata)/ND
rx2av=sum(rxdata*rxdata)/ND
rxsig=sqrt(rx2av-rxav*rxav)
rxdata=rxdata/rxsig
sigma=0.84
llr=2*rxdata/(sigma*sigma)
apmask=0
max_iterations=40
ifer=0
nbadcrc=0
call bpdecode300(llr,apmask,max_iterations,decoded,niterations,cw)
if(niterations.lt.0) call osd300(llr,3,decoded,niterations,cw)
if(niterations.ge.0) call chkcrc10(decoded,nbadcrc)
if(niterations.lt.0 .or. nbadcrc.ne.0) ifer=1
if( ifer.eq.0 ) then
write(cbits,1200) decoded(1:50)
1200 format(50i1)
read(cbits,1202) idat
1202 format(6b8,b2)
idat(7)=ishft(idat(7),6)
call wqdecode(idat,message,itype)
nsnr=nint(xsnr)
freq=fMHz + 1.d-6*(fc1+fc2)
nfdot=0
write(13,1210) datetime,0,nsnr,xdt,freq,message,nfdot
1210 format(a11,2i4,f6.2,f12.7,2x,a22,i3)
write(*,1212) datetime(8:11),nsnr,xdt,freq,nfdot,message,'*',ipks
1212 format(a4,i4,f5.1,f11.6,i3,2x,a22,a1,i4)
goto 888
endif
enddo
enddo
enddo ! fpeaks loop
888 enddo
888 continue
enddo
write(*,1120)
1120 format("<DecodeFinished>")
999 end program wspr5d
subroutine mskseqdet(cdat,pp,bsync,bestbits,cmbest,ncoh)
complex cdat(16*4),cbest(16*4),cideal(16*4)
complex cdf(16*4),cfac
real cm(0:7),cmbest(0:7)
real pp(32)
integer*1 bits(5),bestbits(5),sgn(5)
integer bsync(3)
subroutine getmetric(ib,ps,xmet)
real ps(0:511)
xm1=0
xm0=0
do i=0,511
if( iand(i/ib,1) .eq. 1 .and. ps(i) .gt. xm1 ) xm1=ps(i)
if( iand(i/ib,1) .eq. 0 .and. ps(i) .gt. xm0 ) xm0=ps(i)
enddo
xmet=xm1-xm0
return
end subroutine getmetric
subroutine mskseqdet(ns,cdat,pp,bsync,softbits,ncoh,phase)
!
! Detect sequences of 3, 6, or 9 bits (ns).
! Sync bits are assumed to be known.
!
complex cdat(16*12),cbest(16*12),cideal(16*12)
complex cdf(16*12),cfac,zz
real cm(0:511),cmbest(0:511)
real pp(32),softbits(9)
integer bit(13),bestbits(13),sgn(13)
integer bsync(7)
twopi=8.0*atan(1.0)
dt=30.0*18.0/12000.0
cmax=0;
fbest=0.0;
np=2**ns-1
idfmax=40
if( ncoh .eq. 1 ) idfmax=0
do idf=0,idfmax
@ -217,40 +266,88 @@ do idf=0,idfmax
dphi=twopi*deltaf*dt
cfac=cmplx(cos(dphi),sin(dphi))
cdf=1.0
do i=2,16*4
do i=2,16*(ns-1)
cdf(i)=cdf(i-1)*cfac
enddo
cm=0
ibflag=0
do i=0,7
bits(1)=(bsync(1)+2)/4
bits(2)=iand(i/4,1)
bits(3)=iand(i/2,1)
do i=0,np
bit(1)=(bsync(1)+2)/4
bit(2)=iand(i/(2**(ns-1)),1)
bit(3)=iand(i/(2**(ns-2)),1)
if( bsync(2).ne.0 ) then ! force the barker bits
bits(3)=(bsync(2)+2)/4
bit(3)=(bsync(2)+2)/4
endif
bit(4)=iand(i/(2**(ns-3)),1)
bit(5)=(bsync(3)+2)/4
if( ns .ge. 6 ) then
bit(6)=iand(i/(2**(ns-4)),1)
bit(7)=iand(i/(2**(ns-5)),1)
if( bsync(4).ne.0 ) then ! force the barker bits
bit(7)=(bsync(4)+2)/4
endif
bit(8)=iand(i/(2**(ns-6)),1)
bit(9)=(bsync(5)+2)/4
if( ns .eq. 9 ) then
bit(10)=iand(i/4,1)
bit(11)=iand(i/2,1)
if( bsync(6).ne.0 ) then ! force the barker bits
bit(11)=(bsync(6)+2)/4
endif
bit(12)=iand(i/1,1)
bit(13)=(bsync(7)+2)/4
endif
endif
sgn=2*bit-1
cideal(1:16) =cmplx(sgn(1)*pp(17:32),sgn(2)*pp(1:16))
cideal(17:32) =cmplx(sgn(3)*pp(1:16),sgn(2)*pp(17:32))
cideal(33:48) =cmplx(sgn(3)*pp(17:32),sgn(4)*pp(1:16))
cideal(49:64) =cmplx(sgn(5)*pp(1:16),sgn(4)*pp(17:32))
if( ns .ge. 6 ) then
cideal(65:80) =cmplx(sgn(5)*pp(17:32),sgn(6)*pp(1:16))
cideal(81:96) =cmplx(sgn(7)*pp(1:16),sgn(6)*pp(17:32))
cideal(97:112) =cmplx(sgn(7)*pp(17:32),sgn(8)*pp(1:16))
cideal(113:128)=cmplx(sgn(9)*pp(1:16),sgn(8)*pp(17:32))
if( ns .eq. 9 ) then
cideal(129:144) =cmplx(sgn(9)*pp(17:32),sgn(10)*pp(1:16))
cideal(145:160) =cmplx(sgn(11)*pp(1:16),sgn(10)*pp(17:32))
cideal(161:176) =cmplx(sgn(11)*pp(17:32),sgn(12)*pp(1:16))
cideal(177:192)=cmplx(sgn(13)*pp(1:16),sgn(12)*pp(17:32))
endif
endif
bits(4)=iand(i/1,1)
bits(5)=(bsync(3)+2)/4
sgn=2*bits-1
cideal(1:16)=cmplx(sgn(1)*pp(17:32),sgn(2)*pp(1:16))
cideal(17:32)=cmplx(sgn(3)*pp(1:16),sgn(2)*pp(17:32))
cideal(33:48)=cmplx(sgn(3)*pp(17:32),sgn(4)*pp(1:16))
cideal(49:64)=cmplx(sgn(5)*pp(1:16),sgn(4)*pp(17:32))
cideal=cideal*cdf
cm(i)=abs(sum(cdat*conjg(cideal)))/1.e3
cm(i)=abs(sum(cdat(1:64*ns/3)*conjg(cideal(1:64*ns/3))))/1.e3
if( cm(i) .gt. cmax ) then
ibflag=1
cmax=cm(i)
bestbits=bits
bestbits=bit
cbest=cideal
fbest=deltaf
zz=sum(cdat*conjg(cbest))/1.e3
phase=atan2(imag(zz),real(zz))
endif
enddo
if( ibflag .eq. 1 ) then ! new best found
cmbest=cm
endif
enddo
softbits=0.0
call getmetric(1,cmbest,softbits(ns))
call getmetric(2,cmbest,softbits(ns-1))
call getmetric(4,cmbest,softbits(ns-2))
if( ns .ge. 6 ) then
call getmetric(8,cmbest,softbits(ns-3))
call getmetric(16,cmbest,softbits(ns-4))
call getmetric(32,cmbest,softbits(ns-5))
if( ns .eq. 9 ) then
call getmetric(64,cmbest,softbits(3))
call getmetric(128,cmbest,softbits(2))
call getmetric(256,cmbest,softbits(1))
endif
endif
end subroutine mskseqdet
subroutine downsample(ci,f0,co)
@ -260,11 +357,11 @@ subroutine downsample(ci,f0,co)
df=400.0/NI
ct=ci
call four2a(ct,NI,1,-1,1) !r2c FFT to freq domain
call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain
i0=nint(f0/df)
co=0.0
co(0)=ct(i0)
b=4.0
b=6.0
do i=1,NO/2
arg=(i*df/b)**2
filt=exp(-arg)
@ -275,3 +372,133 @@ subroutine downsample(ci,f0,co)
call four2a(co,NO,1,1,1) !c2c FFT back to time domain
return
end subroutine downsample
subroutine getfc1(c,fs,fa,fb,fc1,xsnr)
! include 'wsprlf_params.f90'
parameter (NZ=288*412)
parameter (NSPS=288)
parameter (N2=2*NSPS)
parameter (NFFT1=16*NSPS)
parameter (NH1=NFFT1/2)
complex c(0:NZ-1) !Complex waveform
complex c2(0:NFFT1-1) !Short spectra
real s(-NH1+1:NH1) !Coarse spectrum
nspec=NZ/N2
df1=fs/NFFT1
s=0.
do k=1,nspec
ia=(k-1)*N2
ib=ia+N2-1
c2(0:N2-1)=c(ia:ib)
c2(N2:)=0.
call four2a(c2,NFFT1,1,-1,1)
do i=0,NFFT1-1
j=i
if(j.gt.NH1) j=j-NFFT1
s(j)=s(j) + real(c2(i))**2 + aimag(c2(i))**2
enddo
enddo
! call smo121(s,NFFT1)
smax=0.
ipk=0
fc1=0.
ia=nint(fa/df1)
ib=nint(fb/df1)
do i=ia,ib
f=i*df1
if(s(i).gt.smax) then
smax=s(i)
ipk=i
fc1=f
endif
! write(51,3001) f,s(i),db(s(i))
! 3001 format(f10.3,e12.3,f10.3)
enddo
! The following is for testing SNR calibration:
sp3n=(s(ipk-1)+s(ipk)+s(ipk+1)) !Sig + 3*noise
base=(sum(s)-sp3n)/(NFFT1-3.0) !Noise per bin
psig=sp3n-3*base !Sig only
pnoise=(2500.0/df1)*base !Noise in 2500 Hz
xsnr=db(psig/pnoise)
xsnr=xsnr+5.0
return
end subroutine getfc1
subroutine getfc2(c,npeaks,fs,fc1,fpks)
! include 'wsprlf_params.f90'
parameter (NZ=288*412)
parameter (NSPS=288)
parameter (N2=2*NSPS)
parameter (NFFT1=16*NSPS)
parameter (NH1=NFFT1/2)
complex c(0:NZ-1) !Complex waveform
complex cs(0:NZ-1) !For computing spectrum
real a(5)
real freqs(413),sp2(413),fpks(npeaks)
integer pkloc(1)
df=fs/NZ
baud=fs/NSPS
a(1)=-fc1
a(2:5)=0.
call twkfreq1(c,NZ,fs,a,cs) !Mix down by fc1
! Filter, square, then FFT to get refined carrier frequency fc2.
call four2a(cs,NZ,1,-1,1) !To freq domain
ia=nint(0.75*baud/df)
cs(ia:NZ-1-ia)=0. !Save only freqs around fc1
! do i=1,NZ/2
! filt=1/(1+((i*df)**2/(0.50*baud)**2)**8)
! cs(i)=cs(i)*filt
! cs(NZ+1-i)=cs(NZ+1-i)*filt
! enddo
call four2a(cs,NZ,1,1,1) !Back to time domain
cs=cs/NZ
!do i=0,NZ-1
!write(51,*) i,real(cs(i)),imag(cs(i))
!enddo
cs=cs*cs !Square the data
call four2a(cs,NZ,1,-1,1) !Compute squared spectrum
! Find two peaks separated by baud
pmax=0.
fc2=0.
! ja=nint(0.3*baud/df)
ja=nint(0.5*baud/df)
k=1
sp2=0.0
do j=-ja,ja
f2=j*df
ia=nint((f2-0.5*baud)/df)
if(ia.lt.0) ia=ia+NZ
ib=nint((f2+0.5*baud)/df)
p=real(cs(ia))**2 + aimag(cs(ia))**2 + &
real(cs(ib))**2 + aimag(cs(ib))**2
if(p.gt.pmax) then
pmax=p
fc2=0.5*f2
endif
freqs(k)=0.5*f2
sp2(k)=p
k=k+1
! write(52,1200) f2,p,db(p)
!1200 format(f10.3,2f15.3)
enddo
do i=1,npeaks
pkloc=maxloc(sp2)
ipk=pkloc(1)
fpks(i)=freqs(ipk)
ipk0=max(1,ipk-2)
ipk1=min(413,ipk+2)
! ipk0=ipk
! ipk1=ipk
sp2(ipk0:ipk1)=0.0
enddo
return
end subroutine getfc2

View File

@ -51,9 +51,9 @@ program wspr5sim
txt=NN*NSPS0/12000.0
call genwspr5(msg,msgsent,itone) !Encode the message, get itone
write(*,1000) f0,xdt,txt,snrdb,nfiles,msgsent
write(*,1000) f0,xdt,txt,snrdb,fspread,delay,nfiles,msgsent
1000 format('f0:',f9.3,' DT:',f6.2,' txt:',f6.1,' SNR:',f6.1, &
' nfiles:',i3,2x,a22)
' fspread:',f6.1,' delay:',f6.1,' nfiles:',i3,2x,a22)
dphi0=twopi*(f0-0.25*baud)*dt
dphi1=twopi*(f0+0.25*baud)*dt
@ -73,19 +73,19 @@ program wspr5sim
enddo
enddo
if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
call watterson(c0,NZ,fs,delay,fspread)
endif
c0=sig*c0 !Scale to requested sig level
call sgran()
do ifile=1,nfiles
c=c0
if(nwav.eq.0) then
if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
call watterson(c,NZ,fs,delay,fspread)
endif
c=c*sig
if(snrdb.lt.90) then
do i=0,NZ-1 !Add gaussian noise at specified SNR
xnoise=gran()
ynoise=gran()
c(i)=c0(i) + cmplx(xnoise,ynoise)
c(i)=c(i) + cmplx(xnoise,ynoise)
enddo
endif
write(fname,1100) ifile

View File

@ -70,19 +70,19 @@ program wspr_fsk8_sim
enddo
enddo
if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
call watterson(c0,NZ,fs,delay,fspread)
endif
c0=sig*c0 !Scale to requested sig level
call sgran()
do ifile=1,nfiles
if(nwav.eq.0) then
c=c0
if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
call watterson(c,NZ,fs,delay,fspread)
endif
c=c*sig
if( snrdb.lt.90) then
do i=0,NZ-1
xnoise=gran()
ynoise=gran()
c(i)=c0(i)+cmplx(xnoise,ynoise)
c(i)=c(i)+cmplx(xnoise,ynoise)
enddo
endif
write(fname,1100) ifile