From 1f9d73963b0c7d44947fe093a601b2cdafb93c7a Mon Sep 17 00:00:00 2001 From: Steven Franke Date: Tue, 3 Apr 2018 14:55:55 +0000 Subject: [PATCH] Update wsprcpm simulator and decoder. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@8603 ab8295b8-cf94-4d9e-aec4-7959e3be5d79 --- lib/fsk4hf/genwsprcpm.f90 | 34 ++- lib/fsk4hf/wsprcpm_params.f90 | 8 +- lib/fsk4hf/wsprcpm_wav.f90 | 17 +- lib/fsk4hf/wsprcpmd.f90 | 539 ++++++++++++++++------------------ lib/fsk4hf/wsprcpmsim.f90 | 21 +- 5 files changed, 286 insertions(+), 333 deletions(-) diff --git a/lib/fsk4hf/genwsprcpm.f90 b/lib/fsk4hf/genwsprcpm.f90 index 0e4b0df7c..49d30a250 100644 --- a/lib/fsk4hf/genwsprcpm.f90 +++ b/lib/fsk4hf/genwsprcpm.f90 @@ -15,20 +15,23 @@ subroutine genwsprcpm(msg,msgsent,itone) integer icw(ND) integer id(NS+ND) integer jd(NS+ND) - integer ipreamble(32) !Long sync vector - integer isync(32) !Long sync vector + integer ipreamble(16) !Freq estimation preamble + integer isync(200) !Long sync vector integer itone(NN) - integer*8 n8 - data ipreamble/1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1/ + data ipreamble/1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1/ data first/.true./ data iuniqueword0/z'30C9E8AD'/ save first,isync,ipreamble if(first) then write(sbits,'(b32.32)') iuniqueword0 - read(sbits,'(32i1)') isync - ipreamble=2*ipreamble-1 - isync=2*isync-1 + read(sbits,'(32i1)') isync(1:32) + read(sbits,'(32i1)') isync(33:64) + read(sbits,'(32i1)') isync(65:96) + read(sbits,'(32i1)') isync(97:128) + read(sbits,'(32i1)') isync(129:160) + read(sbits,'(32i1)') isync(161:192) + read(sbits,'(8i1)') isync(193:200) first=.false. endif @@ -52,17 +55,16 @@ write(*,'(a6,b16.16)') 'icrc: ',icrc write(*,'(50i1,1x,14i1,1x,4i1)') msgbits call encode204(msgbits,codeword) !Encode the test message - icw=2*codeword - 1 !NRZ codeword ! Message structure: -! s32 d200 p32 - itone(1:32)=isync - itone(33:232)=icw - itone(233:264)=ipreamble - -! do i=1,264 -! write(*,*) i,itone(i) -! enddo +! d100 p16 d100 + itone(1:100)=isync(1:100)+2*codeword(1:100) + itone(101:116)=ipreamble+1 + itone(117:216)=isync(101:200)+2*codeword(101:200) + itone=2*itone-3 + do i=1,216 + write(*,*) i,itone(i) + enddo return end subroutine genwsprcpm diff --git a/lib/fsk4hf/wsprcpm_params.f90 b/lib/fsk4hf/wsprcpm_params.f90 index 98c69f121..b09ed86e7 100644 --- a/lib/fsk4hf/wsprcpm_params.f90 +++ b/lib/fsk4hf/wsprcpm_params.f90 @@ -1,11 +1,11 @@ parameter (KK=64) !Information bits (50 + CRC14) ? parameter (ND=200) !Data symbols: LDPC (204,68), r=1/3, don't send last 4 bits -parameter (NS=64) !Sync symbols (2x32) -parameter (NN=NS+ND) !Total symbols (264) +parameter (NS=16) !Sync symbols (16) +parameter (NN=NS+ND) !Total symbols (216) -parameter (NSPS0=5300) !Samples per symbol at 12000 S/s +parameter (NSPS0=6400) !Samples per symbol at 12000 S/s -parameter (NDOWN=53) !Downsample to 100 samples per symbol... +parameter (NDOWN=32) !Downsample to 200 sa/symbol (375 Hz) for candidate selection parameter (NSPS=NSPS0/NDOWN) !Samples per symbol parameter (NZ=NSPS*NN) !Samples in baseband waveform diff --git a/lib/fsk4hf/wsprcpm_wav.f90 b/lib/fsk4hf/wsprcpm_wav.f90 index 32d6525ba..baf49a941 100644 --- a/lib/fsk4hf/wsprcpm_wav.f90 +++ b/lib/fsk4hf/wsprcpm_wav.f90 @@ -1,4 +1,4 @@ -subroutine wsprcpm_wav(baud,xdt,h1,h2,f0,itone,snrdb,iwave) +subroutine wsprcpm_wav(baud,xdt,h,f0,itone,snrdb,iwave) ! Generate iwave() from itone(). @@ -23,23 +23,10 @@ subroutine wsprcpm_wav(baud,xdt,h1,h2,f0,itone,snrdb,iwave) 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 + dphi=twopi*(f0+itone(j)*(h/2.0d0)*baud)*dt do i=1,NSPS0 k=k+1 phi=phi+dphi diff --git a/lib/fsk4hf/wsprcpmd.f90 b/lib/fsk4hf/wsprcpmd.f90 index cf3294c03..281a24156 100644 --- a/lib/fsk4hf/wsprcpmd.f90 +++ b/lib/fsk4hf/wsprcpmd.f90 @@ -4,136 +4,89 @@ program wsprcpmd ! WSPRCPM is a WSPR-like mode based on full-response CPM. ! -! Modulation Capabilities include: -! support for multi-h cpm with two modulation indexes: [h1,h2]. -! h1,h2 (modulation index) are variable; h1=h2=0.5 is MSK, h1=h2=1.0 is standard -! fsk intended for noncoherent demodulation. -! demodulator uses noncoherent sequence detection with variable window size. -! symbol demodulation is done symbol-by-symbol - each symbol is -! estimated using a data frame comprising N symbol intervals, where N can -! be 1, 3, 5, 7, 9, 11. The central symbol is estimated and then the window -! is stepped forward by one symbol. -! soft symbols are decoded by log-domain belief propagation followed by ordered- -! statistics decoding. -! ! Currently configured to use (204,68) r=1/3 LDPC code, regular column weight 3. ! 50 data bits + 14 bit CRC + 4 "0" bits. The 4 "0" bits are unused bits that ! are not transmitted. At the decoder, these bits are treated as "AP" bits. ! This shortens the code to (200,64) r=0.32, slightly decreasing the code rate. ! ! Frame format is: -! s32 d200 p32 (264) channel symbols +! d100 p32 d100 (232) channel symbols ! use crc include 'wsprcpm_params.f90' parameter(NMAX=120*12000) character arg*8,message*22,cbits*50,infile*80,fname*16,datetime*11 + character*22 decodes(100) character*120 data_dir character*32 uwbits character*68 dmsg - complex csync(0:32*100-1) !Sync symbols only, from cbb - complex cpreamble(0:32*100-1) !Sync symbols only, from cbb - complex cp2(0:32*100-1) - complex ctwks(0:32*100-1) - complex ctwkp(0:32*100-1) - complex c2(0:120*12000/53-1) !Complex waveform - complex ctmp(0:4*32*100-1) - complex cframe(0:264*100-1) !Complex waveform - complex cd(0:264*100-1) !Complex waveform - complex c1(0:9,1:2),c0(0:9,1:2) - complex ccor(0:1,264) - complex csum,cp(0:1,1:2),cterm - complex ccohs(0:31) - complex ccohp(0:31) + complex c2(0:120*12000/32-1) !Complex waveform + complex cframe(0:216*200-1) !Complex waveform + complex cd(0:216*10-1) !Complex waveform + complex c1(0:9,0:1),c0(0:9,0:1) + complex ccor(0:1,216) + complex csum,cterm real*8 fMHz real rxdata(ND),llr(204) !Soft symbols - real sbits(264),sbits1(264),sbits3(264) + real sbits(216),sbits1(216),sbits3(216) real ps(0:8191),psbest(0:8191) + real candidates(100,2) integer iuniqueword0 - integer isync(32) !Unique word - integer ipreamble(32) !Preamble vector + integer isync(200) !Unique word + integer isync2(216) + integer ipreamble(16) !Preamble vector integer ihdr(11) integer*2 iwave(NMAX) !Generated full-length waveform integer*1,target :: idat(9) integer*1 decoded(68),apmask(204),cw(204) - integer*1 hbits(264),hbits1(264),hbits3(264) - data ipreamble/1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1/ + integer*1 hbits(216),hbits1(216),hbits3(216) + data ipreamble/1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1/ data iuniqueword0/z'30C9E8AD'/ write(uwbits,'(b32.32)') iuniqueword0 - read(uwbits,'(32i1)') isync - ipreamble=2*ipreamble-1 - isync=2*isync-1 - + read(uwbits,'(32i1)') isync(1:32) + read(uwbits,'(32i1)') isync(33:64) + read(uwbits,'(32i1)') isync(65:96) + read(uwbits,'(32i1)') isync(97:128) + read(uwbits,'(32i1)') isync(129:160) + read(uwbits,'(32i1)') isync(161:192) + read(uwbits,'(8i1)') isync(193:200) + 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) - h1=0.80 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading) - h2=0.80 + h=1.00 !h=0.8 seems to be optimum for AWGN sensitivity (not for fading) twopi=8.0*atan(1.0) - dphi11=twopi*baud*(h1/2.0)*dt - dphi01=-twopi*baud*(h1/2.0)*dt - dphi12=twopi*baud*(h2/2.0)*dt - dphi02=-twopi*baud*(h2/2.0)*dt - k=0 - phi=0.0 - do i=1,32 - if( mod(i,2) .eq. 0 ) then - dphi1=dphi11 - dphi0=dphi01 - else - dphi1=dphi12 - dphi0=dphi02 - endif - dphi=dphi0 - if( isync(i) .eq. 1 ) dphi=dphi1 - do j=1,100 - phi=mod(phi+dphi,twopi) - csync(k)=cmplx(cos(phi),sin(phi)) - k=k+1 - enddo - enddo - k=0 - phi=0.0 - do i=1,32 - if( mod(i,2) .eq. 0 ) then - dphi1=dphi11 - dphi0=dphi01 - else - dphi1=dphi12 - dphi0=dphi02 - endif - dphi=dphi0 - if( ipreamble(i) .eq. 1 ) dphi=dphi1 - do j=1,100 - phi=mod(phi+dphi,twopi) - cpreamble(k)=cmplx(cos(phi),sin(phi)) - k=k+1 - enddo - enddo + isync2(1:100)=isync(1:100) + isync2(101:104)=0 ! This is *not* backwards. + isync2(105:112)=1 + isync2(113:116)=0 + isync2(117:216)=isync(101:200) - dphi1=twopi*baud*(h1/2.0)*dt*10 ! dt*10 is samp interval after downsample - dphi2=twopi*baud*(h2/2.0)*dt*10 ! dt*10 is samp interval after downsample - cp(1,1)=cmplx(cos(dphi1*10),sin(dphi1*10)) - cp(0,1)=conjg(cp(1,1)) - cp(1,2)=cmplx(cos(dphi2*10),sin(dphi2*10)) - cp(0,2)=conjg(cp(1,2)) - do j=1,2 - if( j.eq.1 ) then - dphi=dphi1 +! data sync tone +! 0 0 0 +! 0 1 1 +! 1 0 2 +! 1 1 3 + dphi=twopi*baud*(h/2.0)*dt*20 ! dt*10 is samp interval after downsample + do j=0,1 + if(j.eq.0) then + dphi0=-3*dphi + dphi1=+1*dphi else - dphi=dphi2 + dphi0=-1*dphi + dphi1=+3*dphi endif phi0=0.0 phi1=0.0 do i=0,9 c1(i,j)=cmplx(cos(phi1),sin(phi1)) c0(i,j)=cmplx(cos(phi0),sin(phi0)) - phi1=mod(phi1+dphi,twopi) - phi0=mod(phi0-dphi,twopi) + phi1=mod(phi1+dphi1,twopi) + phi0=mod(phi0+dphi0,twopi) enddo enddo @@ -156,14 +109,14 @@ program wsprcpmd iarg=iarg+2 endif ncoh=1 - npdi=32 + npdi=16 if(arg(1:2).eq.'-c') then call getarg(iarg+1,arg) read(arg,*) ncoh iarg=iarg+2 - npdi=32/ncoh + npdi=16/ncoh endif - write(*,*) 'ncoh: ',ncoh,' npdi: ',npdi +! write(*,*) 'ncoh: ',ncoh,' npdi: ',npdi open(13,file=trim(data_dir)//'/ALL_WSPR.TXT',status='unknown', & position='append') @@ -197,123 +150,43 @@ program wsprcpmd fa=-100.0 fb=100.0 - fs=12000.0/53.0 - npts=120*12000/53 - nsync=32 - - call getcandidate2(c2,npts,fs,fa,fb,fc1,xsnr) !First approx for freq - - fcest=fc1 -do iii=1,2 - izero=226 - dphi=twopi*fcest*dt - ctwks=cmplx(0.0,0.0) - ctwkp=cmplx(0.0,0.0) - phi=0 - do i=0,nsync*NSPS-1 - phi=mod(phi+dphi,twopi) - ctwks(i)=csync(i)*cmplx(cos(phi),sin(phi)) - ctwkp(i)=cpreamble(i)*cmplx(cos(phi),sin(phi)) - enddo - imax=100 - xcmax=-1e32 - do it = -imax,imax - its=izero+it - ccohs=0.0 - do k=0,npdi-1 - is=k*ncoh*nsps - ccohs(k)=sum(c2(its+is:its+is+ncoh*nsps-1)*conjg(ctwks(is:is+ncoh*nsps-1))) - ccohs(k)=ccohs(k)/(ncoh*nsps) - enddo -! term1=sum(abs(ccohs(0:npdi-1))**2) - - itp=izero+it+232*100 - ccohp=0.0 - do k=0,npdi-1 - is=k*ncoh*nsps - ccohp(k)=sum(c2(itp+is:itp+is+ncoh*nsps-1)*conjg(ctwkp(is:is+ncoh*nsps-1))) - ccohp(k)=ccohp(k)/(ncoh*nsps) - enddo - - csum=0.0 - terms=0.0 - do n=1,npdi-1 - do k=n,npdi-1 - csum=csum+ccohs(k)*conjg(ccohs(k-n)) - enddo - terms=terms+abs(csum) - enddo - csum=0.0 - termp=0.0 - do n=1,npdi-1 - do k=n,npdi-1 - csum=csum+ccohp(k)*conjg(ccohp(k-n)) - enddo - termp=termp+abs(csum) - enddo -!write(23,*) it,terms,termp - xmetric=sqrt(terms*termp) - - if( xmetric .gt. xcmax ) then - xcmax=xmetric - ibestt=it + fs=12000.0/32.0 + npts=120*12000.0/32.0 + nsync=16 + call getcandidate2(c2,npts,fs,fa,fb,ncand,candidates) !First approx for freq +ndecodes=0 +do icand=1,ncand + fc0=candidates(icand,1) + xsnr=candidates(icand,2) + xmax=-1e32 + do i=-5,5 + ft=fc0+i*0.2 + call noncoherent_frame_sync(c2,ft,isync2,is,xf1) + if(xf1.gt.xmax) then + xmax=xf1 + fc1=ft + is0=is endif enddo + call coherent_preamble_fsync(c2,ipreamble,nsync,NSPS,is0,fc1,fcest,xp1) + call noncoherent_frame_sync(c2,fcest,isync2,istart,xf2) + write(*,'(i5,i5,i5,4(f11.5,2x))') ifile,iii,istart,fc0,fc1,fcest - istart=izero+ibestt -if(iii .eq. 2) goto 887 - - ctmp=0.0 - ctmp(0:32*100-1)=c2(istart+232*100:istart+264*100-1)*conjg(ctwkp) - call four2a(ctmp,4*32*100,1,-1,1) !c2c FFT to freq domain - xmax=0.0 - ctmp=cshift(ctmp,-200) - do i=150,250 - xa=abs(ctmp(i)) - if(xa.gt.xmax) then - ishift=i - xmax=xa - endif - enddo - dfp=1/(4*5300.0/12000.0*32) - delta=(ishift-200)*dfp -! need to add bounds protection - xm1=abs(ctmp(ishift-1)) - x0=abs(ctmp(ishift)) - xp1=abs(ctmp(ishift+1)) - xint=(log(xm1)-log(xp1))/(log(xm1)+log(xp1)-2*log(x0)) - delta2=delta+xint*dfp/2.0 - fcest=fcest+delta2 -enddo - -887 write(*,'(i4,i5,5(2x,f9.5))') ifile,istart,xcmax,fc1,fcest - xdt=(istart-226)/100.0 - if(abs(xdt).le.0.1) ngood=ngood+1 - xs1=xs1+xdt - xs2=xs2+xdt**2 - fr1=fr1+fc1 - fr2=fr2+fc1**2 - nav=nav+1 -!************** -! fcest=0.0 -! istart=226 - -do ijitter=0,2 - io=ijitter - if(ijitter.eq.2) io=-1 - cframe=c2(istart+io:istart+io+264*100-1) +do ijitter=0,4 + io=-10*(ijitter/2+1) + if(mod(ijitter,2).eq.0) io=10*(ijitter/2) + ib=max(0,istart+io) + cframe=c2(ib:ib+216*200-1) call downsample2(cframe,fcest,cd) - dts=10*dt - s2=sum(cd*conjg(cd))/(10*264) + s2=sum(cd*conjg(cd))/(10*216) cd=cd/sqrt(s2) do nseq=1,7 if( nseq.eq.1 ) then ! noncoherent single-symbol detection sbits1=0.0 - do ibit=1,264 - if( mod(ibit,2).eq.0 ) j=1 - if( mod(ibit,2).eq.1 ) j=2 + do ibit=1,216 + j=isync2(ibit) ib=(ibit-1)*10 ccor(1,ibit)=sum(cd(ib:ib+9)*conjg(c1(0:9,j))) ccor(0,ibit)=sum(cd(ib:ib+9)*conjg(c0(0:9,j))) @@ -334,19 +207,17 @@ do ijitter=0,2 if( nseq.eq. 6 ) nbit=11 if( nseq.eq. 7 ) nbit=13 numseq=2**(nbit) - do ibit=nbit/2+1,264-nbit/2 + do ibit=nbit/2+1,216-nbit/2 ps=0.0 pmax=0.0 do iseq=0,numseq-1 csum=0.0 - cterm=cmplx(1.0,0.0) + cterm=1.0 k=1 do i=nbit-1,0,-1 ibb=iand(iseq/(2**i),1) csum=csum+ccor(ibb,ibit-(nbit/2+1)+k)*cterm - if( mod(ibit-(nbit/2+1)+k,2) .eq. 0 ) j=1 - if( mod(ibit-(nbit/2+1)+k,2) .eq. 1 ) j=2 - cterm=cterm*conjg(cp(ibb,j)) + cterm=-cterm k=k+1 enddo ps(iseq)=abs(csum) @@ -366,7 +237,8 @@ do ijitter=0,2 sbits=sbits3 hbits=hbits3 endif - rxdata(1:200)=sbits(33:232) + rxdata(1:100)=sbits(1:100) + rxdata(101:200)=sbits(117:216); rxav=sum(rxdata(1:200))/200.0 rx2av=sum(rxdata(1:200)*rxdata(1:200))/200.0 rxsig=sqrt(rx2av-rxav*rxav) @@ -401,6 +273,13 @@ do ijitter=0,2 1202 format(8b8,b4) idat(7)=ishft(idat(7),6) call wqdecode(idat,message,itype) + idupe=0 + do i=1,ndecodes + if(decodes(i).eq.message) idupe=1 + enddo + if(idupe.eq.1) goto 888 + ndecodes=ndecodes+1 + decodes(ndecodes)=message nsnr=nint(xsnr) freq=fMHz + 1.d-6*(fc1+fbest) nfdot=0 @@ -413,23 +292,138 @@ do ijitter=0,2 enddo ! nseq enddo !jitter 888 continue +enddo !candidate list enddo !files - avshift=xs1/nav - varshift=xs2/nav - stdshift=sqrt(varshift-avshift**2) - avfr=fr1/nav - varfr=fr2/nav - stdfr=sqrt(varfr-avfr**2) - write(*,*) 'ngood: ',ngood - write(*,'(a7,f7.3,f7.3)') 'shift: ',avshift,stdshift - write(*,*) 'freq: ',avfr,stdfr - write(*,1120) 1120 format("") 999 end program wsprcpmd + +subroutine coherent_preamble_fsync(c2,ipreamble,nsync,nsps,istart,fc0,fc1,xmax) + complex c2(0:120*12000/32-1) + complex cpreamble(0:16*200-1) + complex ctmp1(0:4*16*200-1) + complex ctwkp(0:16*200-1) + complex ccohp(0:15) + integer ipreamble(nsync) + logical first/.true./ + save dt,first,h,twopi,cpreamble + + if(first) then + baud=12000.0/6400.0 + dt=32.0/12000.0 + h=1.00 + twopi=8.0*atan(1.0) + k=0 + phi=0.0 + dphi=twopi*baud*0.5*h*dt + do i=1,16 + dp=dphi + if(ipreamble(i).eq.0) dp=-dphi + do j=1,200 + cpreamble(k)=cmplx(cos(phi),sin(phi)) + phi=mod(phi+dp,twopi) + k=k+1 + enddo + enddo + first=.false. + endif + + dphi=twopi*fc0*dt + ctwkp=cmplx(0.0,0.0) + phi=0 + do i=0,nsync*nsps-1 + ctwkp(i)=cpreamble(i)*cmplx(cos(phi),sin(phi)) + phi=mod(phi+dphi,twopi) + enddo + ipstart=istart+100*200 + ctmp1=0.0 + ctmp1(0:16*200-1)=c2(ipstart:ipstart+16*200-1)*conjg(ctwkp) + call four2a(ctmp1,4*16*200,1,-1,1) !c2c FFT to freq domain + xmax=0.0 + ctmp1=cshift(ctmp1,-200) + dfp=1/(4*6400.0/12000.0*16) + do i=150,250 + xa=abs(ctmp1(i)) + if(xa.gt.xmax) then + ishift=i + xmax=xa + endif + enddo + delta=(ishift-200)*dfp + xm1=abs(ctmp1(ishift-1)) + x0=abs(ctmp1(ishift)) + xp1=abs(ctmp1(ishift+1)) + xint=(log(xm1)-log(xp1))/(log(xm1)+log(xp1)-2*log(x0)) + delta2=delta+xint*dfp/2.0 + fc1=fc0+delta2 + return +end subroutine coherent_preamble_fsync + + +subroutine noncoherent_frame_sync(c2,fc,isync2,istart,ssmax) + complex c2(0:120*12000/32-1) + complex ct0(0:199),ct1(0:199),ct2(0:199),ct3(0:199) + integer isync2(216) + + twopi=8.0*atan(1.0) + h=1.0 + dt=32.0/12000.0 + baud=12000.0/6400.0 + imax=370 ! defines dt search range (375 samples/s) + ssmax=-1e32 + izero=375 + do it = -imax,imax,10 +! noncoherent wspr-type dt estimation + dp0=twopi*(fc-1.5*h*baud)*dt + dp1=twopi*(fc-0.5*h*baud)*dt + dp2=twopi*(fc+0.5*h*baud)*dt + dp3=twopi*(fc+1.5*h*baud)*dt + th0=0.0 + th1=0.0 + th2=0.0 + th3=0.0 + do i=0,199 + ct0(i)=cmplx(cos(th0),sin(th0)) + ct1(i)=cmplx(cos(th1),sin(th1)) + ct2(i)=cmplx(cos(th2),sin(th2)) + ct3(i)=cmplx(cos(th3),sin(th3)) + th0=mod(th0+dp0,twopi) + th1=mod(th1+dp1,twopi) + th2=mod(th2+dp2,twopi) + th3=mod(th3+dp3,twopi) + enddo + ss=0.0 + totp=0.0 + do is=1,216 + i0=izero+it+(is-1)*200 + p0=abs(sum(c2(i0:i0+199)*conjg(ct0))) + p1=abs(sum(c2(i0:i0+199)*conjg(ct1))) + p2=abs(sum(c2(i0:i0+199)*conjg(ct2))) + p3=abs(sum(c2(i0:i0+199)*conjg(ct3))) + p0=sqrt(p0) + p1=sqrt(p1) + p2=sqrt(p2) + p3=sqrt(p3) + + totp=totp+p0+p1+p2+p3 +! cmet=(p1+p3)-(p0+p2) + cmet=max(p1,p3)-max(p0,p2) ! This works better near threshold SNR + if(isync2(is).eq.0) ss=ss-cmet + if(isync2(is).eq.1) ss=ss+cmet + enddo + ss=ss/totp + if(ss.gt.ssmax) then + ioffset=it + ssmax=ss + endif + enddo + istart=izero+ioffset + return +end subroutine noncoherent_frame_sync + subroutine getmetric2(ib,ps,ns,xmet) real ps(0:ns-1) xm1=0 @@ -443,10 +437,10 @@ subroutine getmetric2(ib,ps,ns,xmet) end subroutine getmetric2 subroutine downsample2(ci,f0,co) - parameter(NI=264*100,NH=NI/2,NO=NI/10) ! downsample from 100 samples per symbol to 10 + parameter(NI=216*200,NH=NI/2,NO=NI/20) ! downsample from 200 samples per symbol to 10 complex ci(0:NI-1),ct(0:NI-1) complex co(0:NO-1) - fs=12000.0/53.0 + fs=12000.0/32.0 df=fs/NI ct=ci call four2a(ct,NI,1,-1,1) !c2c FFT to freq domain @@ -454,14 +448,10 @@ subroutine downsample2(ci,f0,co) ct=cshift(ct,i0) co=0.0 co(0)=ct(0) -! b=3.4*0.875/0.715 -! b=2.6*0.5625/0.715 - b=12.0 + b=8.0 do i=1,NO/2 arg=(i*df/b)**2 filt=exp(-arg) -! filt=0.0 -! if( i*df .le. b ) filt=1.0 co(i)=ct(i)*filt co(NO-i)=ct(NI-i)*filt enddo @@ -470,72 +460,62 @@ subroutine downsample2(ci,f0,co) return end subroutine downsample2 -subroutine getcandidate2(c,npts,fs,fa,fb,fc1,xsnr) - parameter(NDAT=100,NFFT1=8*NDAT,NH1=NFFT1/2) +subroutine getcandidate2(c,npts,fs,fa,fb,ncand,candidates) + parameter(NDAT=200,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 w(0:NFFT1-1) - real pi + real candidates(100,2) + integer indx(NFFT2-1) logical first data first/.true./ - save first,w + save first,w,df,csfil if(first) then - pi=4.0*atan(1.0) - do i=0,NFFT1-1 - w(i)=sin(pi*i/(NDAT-1))**2 + df=10*fs/NFFT1 + csfil=cmplx(0.0,0.0) + do i=0,NFFT2-1 + csfil(i)=exp(-((i-NH2)/20.0)**2) enddo + csfil=cshift(csfil,NH2) + call four2a(csfil,NFFT2,1,-1,1) first=.false. endif - nspec=int((npts-NFFT1)/NDAT)+1 - df1=fs/NFFT1 - s=0. - do k=1,nspec - ia=(k-1)*NDAT - ib=ia+NFFT1-1 - c2(0:NFFT1-1)=c(ia:ib)*w - 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 - do i=-NH1+1+4,NH1-4 - ss(i)=sum(s(i-4:i+4))/9.0 - enddo -! do i=-NH1+1+8,NH1-8 -! ss(i)=sum(ss(i-4:i+4))/9.0 -! enddo -do i=-20,20 -write(52,*) i*df1,ss(i) -enddo - - smax=0. - ipk=0 - fc1=0. - ia=nint(fa/df1) - ib=nint(fb/df1) - do i=ia,ib - f=i*df1 - if(ss(i).gt.smax) then - smax=ss(i) - ipk=i - fc1=f - endif - enddo + 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)) - xint=(log(ss(ipk-1))-log(ss(ipk+1)))/(log(ss(ipk-1))+log(ss(ipk+1))-2*log(ss(ipk))) - fc1=fc1+xint*df1/2.0 -! The following is for testing SNR calibration: - sp3n=sum(s(ipk-5:ipk+5)) - base=(sum(s)-sp3n)/(NFFT1-11.0) - psig=sp3n-11*base - pnoise=(2500.0/df1)*base - xsnr=db(psig/pnoise) + 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))-30.0 + endif + enddo +! do i=1,ncand +! write(*,*) i,candidates(i,1),candidates(i,2) +! enddo return end subroutine getcandidate2 @@ -545,9 +525,9 @@ subroutine wsprcpm_downsample(iwave,c) ! Output: Complex data in c(), sampled at 400 Hz include 'wsprcpm_params.f90' - parameter (NMAX=120*12000,NFFT2=NMAX/53) + parameter (NMAX=120*12000,NFFT2=NMAX/32) integer*2 iwave(NMAX) - complex c(0:NZ-1) + complex c(0:NMAX/32-1) complex c1(0:NFFT2-1) complex cx(0:NMAX/2) real x(NMAX) @@ -564,8 +544,7 @@ subroutine wsprcpm_downsample(iwave,c) enddo c1=c1/NFFT2 call four2a(c1,NFFT2,1,1,1) !c2c FFT back to time domain - c=c1(0:NZ-1) - + c=c1(0:NMAX/32-1) return end subroutine wsprcpm_downsample diff --git a/lib/fsk4hf/wsprcpmsim.f90 b/lib/fsk4hf/wsprcpmsim.f90 index a0bbef4a8..6a1f87f3a 100644 --- a/lib/fsk4hf/wsprcpmsim.f90 +++ b/lib/fsk4hf/wsprcpmsim.f90 @@ -42,7 +42,6 @@ program wsprcpmsim fs=12000.0/NDOWN ! dt=1.0/fs !Sample interval (s) tt=NSPS*dt !Duration of "itone" symbols (s) - ts=2*NSPS*dt !Duration of OQPSK symbols (s) baud=1.0/tt !Keying rate for "itone" symbols (baud) txt=NZ*dt !Transmission length (s) bandwidth_ratio=2500.0/(fs/2.0) @@ -55,25 +54,11 @@ program wsprcpmsim 1000 format('f0:',f9.3,' DT:',f6.2,' txt:',f6.1,' SNR:',f6.1, & ' fspread:',f6.1,' delay:',f6.1,' nfiles:',i3,2x,a22) - h1=0.80 - h2=0.80 - dphi11=twopi*(f0+(h1/2.0)*baud)*dt - dphi01=twopi*(f0-(h1/2.0)*baud)*dt - dphi12=twopi*(f0+(h2/2.0)*baud)*dt - dphi02=twopi*(f0-(h2/2.0)*baud)*dt - phi=0.0 + h=1.00 c0=0. k=-1 + nint(xdt/dt) do j=1,NN - if( mod(j,2) .eq. 0 ) then - dphi1=dphi11 - dphi0=dphi01 - else - dphi1=dphi12 - dphi0=dphi02 - endif - dp=dphi1 - if(itone(j).eq.-1) dp=dphi0 + dp=twopi*(f0+itone(j)*(h/2.0)*baud)*dt do i=1,NSPS k=k+1 phi=mod(phi+dp,twopi) @@ -109,7 +94,7 @@ program wsprcpmsim !write(57,*) i,real(c(i)),imag(c(i)) !enddo else - call wsprcpm_wav(baud,xdt,h1,h2,f0,itone,snrdb,iwave) + call wsprcpm_wav(baud,xdt,h,f0,itone,snrdb,iwave) hwav=default_header(12000,NMAX) write(fname,1102) ifile 1102 format('000000_',i4.4,'.wav')