mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-25 13:48:42 -05:00
Add wspr4d and support routines. Not yet working.
This commit is contained in:
Steven Franke
parent
49a7fbbd59
commit
b8ff0941e8
@ -613,6 +613,8 @@ set (wsjt_FSRCS
|
||||
lib/fsk4hf/wspr4sim.f90
|
||||
lib/fsk4hf/genwspr4.f90
|
||||
lib/fsk4hf/gen_wspr4wave.f90
|
||||
lib/fsk4hf/wspr4d.f90
|
||||
lib/fsk4hf/get_wspr4_bitmetrics.f90
|
||||
)
|
||||
|
||||
# temporary workaround for a gfortran v7.3 ICE on Fedora 27 64-bit
|
||||
@ -1362,6 +1364,9 @@ target_link_libraries (ldpcsim174_74 wsjt_fort wsjt_cxx)
|
||||
add_executable (wspr4sim lib/fsk4hf/wspr4sim.f90 wsjtx.rc)
|
||||
target_link_libraries (wspr4sim wsjt_fort wsjt_cxx)
|
||||
|
||||
add_executable (wspr4d lib/fsk4hf/wspr4d.f90 wsjtx.rc)
|
||||
target_link_libraries (wspr4d wsjt_fort wsjt_cxx)
|
||||
|
||||
endif(WSJT_BUILD_UTILS)
|
||||
|
||||
# build the main application
|
||||
|
||||
@ -26,7 +26,7 @@ subroutine genwspr4(msg0,ichk,msgsent,msgbits,i4tone)
|
||||
integer*1 codeword(2*ND)
|
||||
integer*1 msgbits(74),rvec(77)
|
||||
integer icos4a(4),icos4b(4),icos4c(4),icos4d(4)
|
||||
integer*4 ncrc24
|
||||
integer ncrc24
|
||||
logical unpk77_success
|
||||
data icos4a/0,1,3,2/
|
||||
data icos4b/1,0,2,3/
|
||||
@ -59,7 +59,6 @@ subroutine genwspr4(msg0,ichk,msgsent,msgbits,i4tone)
|
||||
read(c24,'(24i1)') msgbits(51:74)
|
||||
|
||||
if(ichk.eq.1) go to 999
|
||||
read(c77,'(74i1)',err=1) msgbits
|
||||
if(unpk77_success) go to 2
|
||||
1 msgbits=0
|
||||
itone=0
|
||||
@ -68,8 +67,7 @@ subroutine genwspr4(msg0,ichk,msgsent,msgbits,i4tone)
|
||||
|
||||
entry get_wspr4_tones_from_74bits(msgbits,i4tone)
|
||||
|
||||
2 msgbits=mod(msgbits+rvec(1:74),2)
|
||||
call encode174_74(msgbits,codeword)
|
||||
2 call encode174_74(msgbits,codeword)
|
||||
|
||||
! Grayscale mapping:
|
||||
! bits tone
|
||||
|
||||
118
lib/fsk4hf/get_wspr4_bitmetrics.f90
Normal file
118
lib/fsk4hf/get_wspr4_bitmetrics.f90
Normal file
@ -0,0 +1,118 @@
|
||||
subroutine get_wspr4_bitmetrics(cd,bitmetrics,badsync)
|
||||
|
||||
include 'wspr4_params.f90'
|
||||
parameter (NSS=16)
|
||||
complex cd(0:NN*NSS-1)
|
||||
complex cs(0:3,NN)
|
||||
complex csymb(NSS)
|
||||
integer icos4a(0:3),icos4b(0:3),icos4c(0:3),icos4d(0:3)
|
||||
integer graymap(0:3)
|
||||
integer ip(1)
|
||||
logical one(0:255,0:7) ! 256 4-symbol sequences, 8 bits
|
||||
logical first
|
||||
logical badsync
|
||||
real bitmetrics(2*NN,3)
|
||||
real s2(0:255)
|
||||
real s4(0:3,NN)
|
||||
|
||||
data icos4a/0,1,3,2/
|
||||
data icos4b/1,0,2,3/
|
||||
data icos4c/2,3,1,0/
|
||||
data icos4d/3,2,0,1/
|
||||
data graymap/0,1,3,2/
|
||||
data first/.true./
|
||||
save first,one
|
||||
|
||||
if(first) then
|
||||
one=.false.
|
||||
do i=0,255
|
||||
do j=0,7
|
||||
if(iand(i,2**j).ne.0) one(i,j)=.true.
|
||||
enddo
|
||||
enddo
|
||||
first=.false.
|
||||
endif
|
||||
|
||||
do k=1,NN
|
||||
i1=(k-1)*NSS
|
||||
csymb=cd(i1:i1+NSS-1)
|
||||
call four2a(csymb,NSS,1,-1,1)
|
||||
cs(0:3,k)=csymb(1:4)
|
||||
s4(0:3,k)=abs(csymb(1:4))
|
||||
enddo
|
||||
|
||||
! Sync quality check
|
||||
is1=0
|
||||
is2=0
|
||||
is3=0
|
||||
is4=0
|
||||
badsync=.false.
|
||||
ibmax=0
|
||||
|
||||
do k=1,4
|
||||
ip=maxloc(s4(:,k))
|
||||
if(icos4a(k-1).eq.(ip(1)-1)) is1=is1+1
|
||||
ip=maxloc(s4(:,k+33))
|
||||
if(icos4b(k-1).eq.(ip(1)-1)) is2=is2+1
|
||||
ip=maxloc(s4(:,k+66))
|
||||
if(icos4c(k-1).eq.(ip(1)-1)) is3=is3+1
|
||||
ip=maxloc(s4(:,k+99))
|
||||
if(icos4d(k-1).eq.(ip(1)-1)) is4=is4+1
|
||||
enddo
|
||||
nsync=is1+is2+is3+is4 !Number of correct hard sync symbols, 0-16
|
||||
|
||||
badsync=.false.
|
||||
! if(nsync .lt. 8) then
|
||||
! badsync=.true.
|
||||
! return
|
||||
! endif
|
||||
|
||||
do nseq=1,3 !Try coherent sequences of 1, 2, and 4 symbols
|
||||
if(nseq.eq.1) nsym=1
|
||||
if(nseq.eq.2) nsym=2
|
||||
if(nseq.eq.3) nsym=4
|
||||
nt=2**(2*nsym)
|
||||
do ks=1,NN-nsym+1,nsym !87+16=103 symbols.
|
||||
amax=-1.0
|
||||
do i=0,nt-1
|
||||
i1=i/64
|
||||
i2=iand(i,63)/16
|
||||
i3=iand(i,15)/4
|
||||
i4=iand(i,3)
|
||||
if(nsym.eq.1) then
|
||||
s2(i)=abs(cs(graymap(i4),ks))
|
||||
elseif(nsym.eq.2) then
|
||||
s2(i)=abs(cs(graymap(i3),ks)+cs(graymap(i4),ks+1))
|
||||
elseif(nsym.eq.4) then
|
||||
s2(i)=abs(cs(graymap(i1),ks ) + &
|
||||
cs(graymap(i2),ks+1) + &
|
||||
cs(graymap(i3),ks+2) + &
|
||||
cs(graymap(i4),ks+3) &
|
||||
)
|
||||
else
|
||||
print*,"Error - nsym must be 1, 2, or 4."
|
||||
endif
|
||||
enddo
|
||||
ipt=1+(ks-1)*2
|
||||
if(nsym.eq.1) ibmax=1
|
||||
if(nsym.eq.2) ibmax=3
|
||||
if(nsym.eq.4) ibmax=7
|
||||
do ib=0,ibmax
|
||||
bm=maxval(s2(0:nt-1),one(0:nt-1,ibmax-ib)) - &
|
||||
maxval(s2(0:nt-1),.not.one(0:nt-1,ibmax-ib))
|
||||
if(ipt+ib.gt.2*NN) cycle
|
||||
bitmetrics(ipt+ib,nseq)=bm
|
||||
enddo
|
||||
enddo
|
||||
enddo
|
||||
|
||||
bitmetrics(205:206,2)=bitmetrics(205:206,1)
|
||||
bitmetrics(201:204,3)=bitmetrics(201:204,2)
|
||||
bitmetrics(205:206,3)=bitmetrics(205:206,1)
|
||||
|
||||
call normalizebmet(bitmetrics(:,1),2*NN)
|
||||
call normalizebmet(bitmetrics(:,2),2*NN)
|
||||
call normalizebmet(bitmetrics(:,3),2*NN)
|
||||
return
|
||||
|
||||
end subroutine get_wspr4_bitmetrics
|
||||
433
lib/fsk4hf/wspr4d.f90
Normal file
433
lib/fsk4hf/wspr4d.f90
Normal file
@ -0,0 +1,433 @@
|
||||
program wspr4d
|
||||
|
||||
! Decode WSPR4 data read from *.c2 or *.wav files.
|
||||
|
||||
use packjt77
|
||||
include 'wspr4_params.f90'
|
||||
parameter (NSPS2=NSPS/32)
|
||||
character arg*8,cbits*50,infile*80,fname*16,datetime*11
|
||||
character ch1*1,ch4*4,cseq*31
|
||||
character*22 decodes(100)
|
||||
character*37 msg
|
||||
character*120 data_dir
|
||||
character*32 uwbits
|
||||
character*77 c77
|
||||
complex c2(0:NMAX/32-1) !Complex waveform
|
||||
complex cframe(0:105*NSPS2-1) !Complex waveform
|
||||
complex cd(0:105*16-1) !Complex waveform
|
||||
complex c1(0:9,0:3),c0(0:9,0:3)
|
||||
complex ccor(0:3,103)
|
||||
complex cp(0:3,0:1)
|
||||
complex csum,cterm
|
||||
complex ctwk(NSPS2*4)
|
||||
real*8 fMHz
|
||||
real rxdata(2*ND),llr(174),llra(174),llrb(174),llrc(174)
|
||||
real sbits(174),sbits1(174),sbits3(174)
|
||||
real ps(0:8191),psbest(0:8191)
|
||||
real candidates(100,2)
|
||||
real bitmetrics(206,3)
|
||||
integer iuniqueword0
|
||||
integer ihdr(11)
|
||||
integer*2 iwave(NMAX) !Generated full-length waveform
|
||||
integer*1 decoded(74),apmask(174),cw(174)
|
||||
integer*1 hbits(206),hbits1(206),hbits3(206)
|
||||
integer*1 message(50)
|
||||
integer*1 rvec(77)
|
||||
logical badsync,unpk77_success
|
||||
data rvec/0,1,0,0,1,0,1,0,0,1,0,1,1,1,1,0,1,0,0,0,1,0,0,1,1,0,1,1,0, &
|
||||
1,0,0,1,0,1,1,0,0,0,0,1,0,0,0,1,0,1,0,0,1,1,1,1,0,0,1,0,1, &
|
||||
0,1,0,1,0,1,1,0,1,1,1,1,1,0,0,0,1,0,1/
|
||||
|
||||
fs=12000.0/NDOWN !Sample rate
|
||||
dt=1.0/fs !Sample interval (s)
|
||||
tt=NSPS*dt !Duration of "itone" symbols (s)
|
||||
baud=1.0/tt !Keying rate for "itone" symbols (baud)
|
||||
txt=NZ*dt !Transmission length (s)
|
||||
h=0.50 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading)
|
||||
twopi=8.0*atan(1.0)
|
||||
pi=4.0*atan(1.0)
|
||||
|
||||
nargs=iargc()
|
||||
if(nargs.lt.1) then
|
||||
print*,'Usage: wspr4d [-a <data_dir>] [-f fMHz] [-c ncoh] [-h h] file1 [file2 ...]'
|
||||
go to 999
|
||||
endif
|
||||
iarg=1
|
||||
data_dir="."
|
||||
call getarg(iarg,arg)
|
||||
if(arg(1:2).eq.'-a') then
|
||||
call getarg(iarg+1,data_dir)
|
||||
iarg=iarg+2
|
||||
endif
|
||||
call getarg(iarg,arg)
|
||||
if(arg(1:2).eq.'-f') then
|
||||
call getarg(iarg+1,arg)
|
||||
read(arg,*) fMHz
|
||||
iarg=iarg+2
|
||||
endif
|
||||
ncoh=1
|
||||
if(arg(1:2).eq.'-h') then
|
||||
call getarg(iarg+1,arg)
|
||||
read(arg,*) h
|
||||
iarg=iarg+2
|
||||
endif
|
||||
|
||||
open(13,file=trim(data_dir)//'/ALL_WSPR.TXT',status='unknown', &
|
||||
position='append')
|
||||
|
||||
xs1=0.0
|
||||
xs2=0.0
|
||||
fr1=0.0
|
||||
fr2=0.0
|
||||
nav=0
|
||||
ngood=0
|
||||
fcsum=0.0
|
||||
fcsum2=0.0
|
||||
xsum=0.0
|
||||
xsum2=0.0
|
||||
do ifile=iarg,nargs
|
||||
call getarg(ifile,infile)
|
||||
open(10,file=infile,status='old',access='stream')
|
||||
j1=index(infile,'.c2')
|
||||
j2=index(infile,'.wav')
|
||||
if(j1.gt.0) then
|
||||
read(10,end=999) fname,ntrmin,fMHz,c2
|
||||
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 wspr4_downsample(iwave,c2)
|
||||
else
|
||||
print*,'Wrong file format?'
|
||||
go to 999
|
||||
endif
|
||||
close(10)
|
||||
|
||||
fa=-100.0
|
||||
fb=100.0
|
||||
fs=12000.0/32.0
|
||||
npts=120*12000.0/32.0
|
||||
nsync=16
|
||||
|
||||
call getcandidate4(c2,npts,fs,fa,fb,ncand,candidates) !First approx for freq
|
||||
|
||||
ndecodes=0
|
||||
do icand=1,1
|
||||
fc0=candidates(icand,1)
|
||||
xsnr=candidates(icand,2)
|
||||
xmax=-1e32
|
||||
smax=0.0
|
||||
fc1=fc0-1.50*(fs/416.0)
|
||||
do if=-20,20
|
||||
df=if*0.02
|
||||
fc=fc1+df
|
||||
do is=300,450,5
|
||||
call coherent_sync(c2,is,fc,1,sync)
|
||||
if(sync.gt.smax) then
|
||||
fc2=fc
|
||||
isbest=is
|
||||
smax=sync
|
||||
endif
|
||||
enddo
|
||||
enddo
|
||||
write(*,*) -1.50*(fs/416),fc1,fc2,isbest
|
||||
fcsum=fcsum+fc2
|
||||
fcsum2=fcsum2+fc2*fc2
|
||||
xsum=xsum+isbest
|
||||
xsum2=xsum2+isbest*isbest
|
||||
istart=isbest
|
||||
fcest=fc2
|
||||
!genie sync
|
||||
! istart=375
|
||||
! fcest=0.0-1.50*(fs/416)
|
||||
h=1.0
|
||||
cframe=c2(istart:istart+105*416-1)
|
||||
call downsample4(cframe,fcest,h,cd)
|
||||
s2=sum(cd*conjg(cd))/(16*105)
|
||||
cd=cd/sqrt(s2)
|
||||
call get_wspr4_bitmetrics(cd,bitmetrics,badsync)
|
||||
! if(badsync) cycle
|
||||
|
||||
hbits=0
|
||||
where(bitmetrics(:,1).ge.0) hbits=1
|
||||
ns1=count(hbits( 1: 8).eq.(/0,0,0,1,1,0,1,1/))
|
||||
ns2=count(hbits( 67: 74).eq.(/0,1,0,0,1,1,1,0/))
|
||||
ns3=count(hbits(133:140).eq.(/1,1,1,0,0,1,0,0/))
|
||||
ns4=count(hbits(199:206).eq.(/1,0,1,1,0,0,0,1/))
|
||||
nsync_qual=ns1+ns2+ns3+ns4
|
||||
! if(nsync_qual.lt. 20) cycle
|
||||
|
||||
scalefac=2.83
|
||||
llra( 1: 58)=bitmetrics( 9: 66, 1)
|
||||
llra( 59:116)=bitmetrics( 75:132, 1)
|
||||
llra(117:174)=bitmetrics(141:198, 1)
|
||||
llra=scalefac*llra
|
||||
llrb( 1: 58)=bitmetrics( 9: 66, 2)
|
||||
llrb( 59:116)=bitmetrics( 75:132, 2)
|
||||
llrb(117:174)=bitmetrics(141:198, 2)
|
||||
llrb=scalefac*llrb
|
||||
llrc( 1: 58)=bitmetrics( 9: 66, 3)
|
||||
llrc( 59:116)=bitmetrics( 75:132, 3)
|
||||
llrc(117:174)=bitmetrics(141:198, 3)
|
||||
llrc=scalefac*llrc
|
||||
apmask=0
|
||||
max_iterations=40
|
||||
|
||||
do itry=3,1,-1
|
||||
if(itry.eq.1) llr=llra
|
||||
if(itry.eq.2) llr=llrb
|
||||
if(itry.eq.3) llr=llrc
|
||||
nhardbp=0
|
||||
nhardosd=0
|
||||
call bpdecode174_74(llr,apmask,max_iterations,message,cw,nhardbp,niterations)
|
||||
Keff=64
|
||||
if(nhardbp.lt.0) call osd174_74(llr,Keff,apmask,5,message,cw,nhardosd,dmin)
|
||||
!write(*,*) ifile,nhardosd,dmin
|
||||
if(nhardbp.ge.0 .or. nhardosd.ge.0) then
|
||||
write(c77,'(50i1)') message
|
||||
c77(51:77)='000000000000000000000110000'
|
||||
call unpack77(c77,0,msg,unpk77_success)
|
||||
if(unpk77_success .and. index(msg,'K9AN').gt.0) then
|
||||
write(*,1100) ifile,fc0,xsnr,msg(1:14),itry,nhardbp,nhardosd,dmin
|
||||
1100 format(i5,2x,f8.2,2x,f8.2,2x,a14,i4,i4,i4,f7.2)
|
||||
exit
|
||||
else
|
||||
cycle
|
||||
endif
|
||||
endif
|
||||
enddo
|
||||
enddo !candidate list
|
||||
enddo !files
|
||||
nfiles=nargs-iarg+1
|
||||
fcav=fcsum/nfiles
|
||||
fcvar=fcsum2/nfiles-fcav**2
|
||||
fcstd=sqrt(fcvar)
|
||||
xav=xsum/nfiles
|
||||
xvar=xsum2/nfiles-xav**2
|
||||
xstd=sqrt(xvar)
|
||||
write(*,*) 'averages, nfiles: ',nfiles
|
||||
write(*,*) ' avg freq std avg offset std'
|
||||
write(*,'(f9.4,2x,f8.4,2x,f8.1,2x,f8.1,2x)') fcav,fcstd,xav,xstd
|
||||
write(*,1120)
|
||||
1120 format("<DecodeFinished>")
|
||||
|
||||
999 end program wspr4d
|
||||
|
||||
subroutine coherent_sync(cd0,i0,f0,itwk,sync)
|
||||
|
||||
! Compute sync power for a complex, downsampled FT4 signal.
|
||||
|
||||
include 'wspr4_params.f90'
|
||||
parameter(NP=NMAX/NDOWN,NSS=NSPS/NDOWN)
|
||||
complex cd0(0:NP-1)
|
||||
complex csynca(4*NSS),csyncb(4*NSS),csyncc(4*NSS),csyncd(4*NSS)
|
||||
complex csync2(4*NSS)
|
||||
complex ctwk(4*NSS)
|
||||
complex z1,z2,z3,z4
|
||||
logical first
|
||||
integer icos4a(0:3),icos4b(0:3),icos4c(0:3),icos4d(0:3)
|
||||
data icos4a/0,1,3,2/
|
||||
data icos4b/1,0,2,3/
|
||||
data icos4c/2,3,1,0/
|
||||
data icos4d/3,2,0,1/
|
||||
data first/.true./
|
||||
save first,twopi,csynca,csyncb,csyncc,csyncd,fac
|
||||
|
||||
p(z1)=(real(z1*fac)**2 + aimag(z1*fac)**2)**0.5 !Statement function for power
|
||||
|
||||
if( first ) then
|
||||
twopi=8.0*atan(1.0)
|
||||
k=1
|
||||
phia=0.0
|
||||
phib=0.0
|
||||
phic=0.0
|
||||
phid=0.0
|
||||
do i=0,3
|
||||
dphia=twopi*icos4a(i)/real(NSS)
|
||||
dphib=twopi*icos4b(i)/real(NSS)
|
||||
dphic=twopi*icos4c(i)/real(NSS)
|
||||
dphid=twopi*icos4d(i)/real(NSS)
|
||||
do j=1,NSS
|
||||
csynca(k)=cmplx(cos(phia),sin(phia))
|
||||
csyncb(k)=cmplx(cos(phib),sin(phib))
|
||||
csyncc(k)=cmplx(cos(phic),sin(phic))
|
||||
csyncd(k)=cmplx(cos(phid),sin(phid))
|
||||
phia=mod(phia+dphia,twopi)
|
||||
phib=mod(phib+dphib,twopi)
|
||||
phic=mod(phic+dphic,twopi)
|
||||
phid=mod(phid+dphid,twopi)
|
||||
k=k+1
|
||||
enddo
|
||||
enddo
|
||||
first=.false.
|
||||
fac=1.0/(4.0*NSS)
|
||||
endif
|
||||
|
||||
i1=i0 !four Costas arrays
|
||||
i2=i0+33*NSS
|
||||
i3=i0+66*NSS
|
||||
i4=i0+99*NSS
|
||||
|
||||
z1=0.
|
||||
z2=0.
|
||||
z3=0.
|
||||
z4=0.
|
||||
|
||||
if(itwk.eq.1) then
|
||||
dt=1/(12000.0/32.0)
|
||||
dphi=twopi*f0*dt
|
||||
phi=0.0
|
||||
do i=1,4*NSS
|
||||
ctwk(i)=cmplx(cos(phi),sin(phi))
|
||||
phi=mod(phi+dphi,twopi)
|
||||
enddo
|
||||
endif
|
||||
|
||||
if(itwk.eq.1) csync2=ctwk*csynca !Tweak the frequency
|
||||
z1=0.
|
||||
if(i1.ge.0 .and. i1+4*NSS-1.le.NP-1) then
|
||||
z1=sum(cd0(i1:i1+4*NSS-1)*conjg(csync2))
|
||||
elseif( i1.lt.0 ) then
|
||||
npts=(i1+4*NSS-1)/2
|
||||
if(npts.le.32) then
|
||||
z1=0.
|
||||
else
|
||||
z1=sum(cd0(0:i1+4*NSS-1)*conjg(csync2(4*NSS-npts:)))
|
||||
endif
|
||||
endif
|
||||
|
||||
if(itwk.eq.1) csync2=ctwk*csyncb !Tweak the frequency
|
||||
if(i2.ge.0 .and. i2+4*NSS-1.le.NP-1) z2=sum(cd0(i2:i2+4*NSS-1)*conjg(csync2))
|
||||
|
||||
if(itwk.eq.1) csync2=ctwk*csyncc !Tweak the frequency
|
||||
if(i3.ge.0 .and. i3+4*NSS-1.le.NP-1) z3=sum(cd0(i3:i3+4*NSS-1)*conjg(csync2))
|
||||
|
||||
if(itwk.eq.1) csync2=ctwk*csyncd !Tweak the frequency
|
||||
z4=0.
|
||||
if(i4.ge.0 .and. i4+4*NSS-1.le.NP-1) then
|
||||
z4=sum(cd0(i4:i4+4*NSS-1)*conjg(csync2))
|
||||
elseif( i4+4*NSS-1.gt.NP-1 ) then
|
||||
npts=(NP-1-i4+1)
|
||||
if(npts.le.32) then
|
||||
z4=0.
|
||||
else
|
||||
z4=sum(cd0(i4:i4+2*npts-1)*conjg(csync2(1:npts)))
|
||||
endif
|
||||
endif
|
||||
|
||||
sync = p(z1) + p(z2) + p(z3) + p(z4)
|
||||
|
||||
return
|
||||
end subroutine coherent_sync
|
||||
|
||||
subroutine downsample4(ci,f0,h,co)
|
||||
parameter(NI=105*416,NH=NI/2,NO=NI/26) ! downsample from 416 samples per symbol to 16
|
||||
complex ci(0:NI-1),ct(0:NI-1)
|
||||
complex co(0:NO-1)
|
||||
fs=12000.0/32.0
|
||||
df=fs/NI
|
||||
ct=ci
|
||||
call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain
|
||||
i0=nint(f0/df)
|
||||
ct=cshift(ct,i0)
|
||||
co=0.0
|
||||
co(0)=ct(0)
|
||||
b=max(1.0,h)*8.0
|
||||
do i=1,NO/2
|
||||
arg=(i*df/b)**2
|
||||
filt=exp(-arg)
|
||||
co(i)=ct(i)*filt
|
||||
co(NO-i)=ct(NI-i)*filt
|
||||
enddo
|
||||
co=co/NO
|
||||
call four2a(co,NO,1,1,1) !c2c FFT back to time domain
|
||||
return
|
||||
end subroutine downsample4
|
||||
|
||||
subroutine getcandidate4(c,npts,fs,fa,fb,ncand,candidates)
|
||||
parameter(NFFT1=120*12000/32,NH1=NFFT1/2,NFFT2=120*12000/320,NH2=NFFT2/2)
|
||||
complex c(0:npts-1) !Complex waveform
|
||||
complex cc(0:NFFT1-1)
|
||||
complex csfil(0:NFFT2-1)
|
||||
complex cwork(0:NFFT2-1)
|
||||
real bigspec(0:NFFT2-1)
|
||||
complex c2(0:NFFT1-1) !Short spectra
|
||||
real s(-NH1+1:NH1) !Coarse spectrum
|
||||
real ss(-NH1+1:NH1) !Smoothed coarse spectrum
|
||||
real candidates(100,2)
|
||||
integer indx(NFFT2-1)
|
||||
logical first
|
||||
data first/.true./
|
||||
save first,w,df,csfil
|
||||
|
||||
if(first) then
|
||||
df=10*fs/NFFT1
|
||||
csfil=cmplx(0.0,0.0)
|
||||
do i=0,NFFT2-1
|
||||
csfil(i)=exp(-((i-NH2)/32.0)**2) ! revisit this
|
||||
enddo
|
||||
csfil=cshift(csfil,NH2)
|
||||
call four2a(csfil,NFFT2,1,-1,1)
|
||||
first=.false.
|
||||
endif
|
||||
|
||||
cc=cmplx(0.0,0.0)
|
||||
cc(0:npts-1)=c;
|
||||
call four2a(cc,NFFT1,1,-1,1)
|
||||
cc=abs(cc)**2
|
||||
call four2a(cc,NFFT1,1,-1,1)
|
||||
cwork(0:NH2)=cc(0:NH2)*conjg(csfil(0:NH2))
|
||||
cwork(NH2+1:NFFT2-1)=cc(NFFT1-NH2+1:NFFT1-1)*conjg(csfil(NH2+1:NFFT2-1))
|
||||
|
||||
call four2a(cwork,NFFT2,1,+1,1)
|
||||
bigspec=cshift(real(cwork),-NH2)
|
||||
il=NH2+fa/df
|
||||
ih=NH2+fb/df
|
||||
nnl=ih-il+1
|
||||
call indexx(bigspec(il:il+nnl-1),nnl,indx)
|
||||
xn=bigspec(il-1+indx(nint(0.3*nnl)))
|
||||
bigspec=bigspec/xn
|
||||
ncand=0
|
||||
do i=il,ih
|
||||
if((bigspec(i).gt.bigspec(i-1)).and. &
|
||||
(bigspec(i).gt.bigspec(i+1)).and. &
|
||||
(bigspec(i).gt.1.15).and.ncand.lt.100) then
|
||||
ncand=ncand+1
|
||||
candidates(ncand,1)=df*(i-NH2)
|
||||
candidates(ncand,2)=10*log10(bigspec(i)-1)-26.0
|
||||
endif
|
||||
enddo
|
||||
return
|
||||
end subroutine getcandidate4
|
||||
|
||||
subroutine wspr4_downsample(iwave,c)
|
||||
|
||||
! Input: i*2 data in iwave() at sample rate 12000 Hz
|
||||
! Output: Complex data in c(), sampled at 375 Hz
|
||||
|
||||
include 'wspr4_params.f90'
|
||||
parameter (NFFT2=NMAX/32)
|
||||
integer*2 iwave(NMAX)
|
||||
complex c(0:NMAX/32-1)
|
||||
complex c1(0:NFFT2-1)
|
||||
complex cx(0:NMAX/2)
|
||||
real x(NMAX)
|
||||
equivalence (x,cx)
|
||||
|
||||
df=12000.0/NMAX
|
||||
x=iwave
|
||||
call four2a(x,NMAX,1,-1,0) !r2c FFT to freq domain
|
||||
i0=nint(1500.0/df)
|
||||
c1(0)=cx(i0)
|
||||
do i=1,NFFT2/2
|
||||
c1(i)=cx(i0+i)
|
||||
c1(NFFT2-i)=cx(i0-i)
|
||||
enddo
|
||||
c1=c1/NFFT2
|
||||
call four2a(c1,NFFT2,1,1,1) !c2c FFT back to time domain
|
||||
c=c1(0:NMAX/32-1)
|
||||
return
|
||||
end subroutine wspr4_downsample
|
||||
|
||||
@ -61,7 +61,7 @@ program wspr4sim
|
||||
write(*,'(28i1,1x,i1,1x,28i1,1x,i1,1x,i1,1x,15i1,1x,3i1)') msgbits(1:77)
|
||||
else
|
||||
write(*,'(a14)') 'Message bits: '
|
||||
write(*,'(77i1)') msgbits
|
||||
write(*,'(50i1,1x,24i1)') msgbits
|
||||
endif
|
||||
write(*,*)
|
||||
write(*,'(a17)') 'Channel symbols: '
|
||||
@ -73,8 +73,7 @@ program wspr4sim
|
||||
fsample=12000.0
|
||||
icmplx=1
|
||||
call gen_wspr4wave(itone,NN,NSPS,fsample,f0,c0,wave,icmplx,NMAX)
|
||||
|
||||
k=nint((xdt+0.5)/dt)-NSPS
|
||||
k=nint((xdt+1.0)/dt)-NSPS
|
||||
c0=cshift(c0,-k)
|
||||
if(k.gt.0) c0(0:k-1)=0.0
|
||||
if(k.lt.0) c0(NMAX+k:NMAX-1)=0.0
|
||||
|
||||
Loading…
Reference in New Issue
Block a user