program QRA64code ! Provides examples of message packing, bit and symbol ordering, ! QRA (63,12) encoding, and other necessary details of the QRA64 ! protocol. Also permits simple simulations to measure performance ! on an AWGN channel with secure time and frequency synchronization. ! Return codes from qra64_dec: ! irc=0 [? ? ?] AP0 (decoding with no a-priori information) ! irc=1 [CQ ? ?] AP27 ! irc=2 [CQ ? ] AP42 ! irc=3 [CALL ? ?] AP29 ! irc=4 [CALL ? ] AP44 ! irc=5 [CALL CALL ?] AP57 use packjt character*22 msg,msg0,msg1,decoded,cok*3,msgtype*10,arg*12 character*6 mycall logical ltext integer dgen(12),sent(63),dec(12) real s3(0:63,1:63) include 'testmsg.f90' nargs=iargc() if(nargs.lt.1) then print*,'Usage: qra64code "message" [snr2500] [Nrpt]' print*,' qra64code -t [snr2500]' go to 999 endif call getarg(1,msg) !Get message from command line snr2500=10.0 if(nargs.ge.2) then call getarg(2,arg) read(arg,*) snr2500 endif sig=sqrt(2.0)*10.0**(0.05*(snr2500+29.7)) nmsg=1 nrpt=1 if(msg(1:2).eq."-t") then nmsg=NTEST else if(nargs.ge.3) then call getarg(3,arg) read(arg,*) nrpt endif endif write(*,1010) 1010 format(" Message Decoded Err? Type rc"/77("-")) ngood=0 nbad=0 do nn=1,nrpt do imsg=1,nmsg if(nmsg.gt.1) msg=testmsg(imsg) call fmtmsg(msg,iz) !To upper, collapse mult blanks msg0=msg !Input message call chkmsg(msg,cok,nspecial,flip) !See if it includes "OOO" report msg1=msg !Message without "OOO" call packmsg(msg1,dgen,itype) !Pack message into 12 six-bit bytes msgtype="" if(itype.eq.1) msgtype="Std Msg" if(itype.eq.2) msgtype="Type 1 pfx" if(itype.eq.3) msgtype="Type 1 sfx" if(itype.eq.4) msgtype="Type 2 pfx" if(itype.eq.5) msgtype="Type 2 sfx" if(itype.eq.6) msgtype="Free text" call qra64_enc(dgen,sent) !Encode using QRA64 ! Generate a simulated s3() array with moderately high S/N do j=1,63 do i=0,63 x=gran() y=gran() s3(i,j)=x*x + y*y enddo k=sent(j) x=gran() + sig y=gran() s3(k,j)=x*x + y*y enddo i1=index(msg1,' ') mycall=' ' if(i1.ge.4) mycall=msg(1:i1-1) call packcall(mycall,nmycall,ltext) call qra64_dec(s3,nmycall,dec,snr,irc) !Decode decoded=" " if(irc.ge.0) then call unpackmsg(dec,decoded) !Unpack the user message call fmtmsg(decoded,iz) else dec=0 endif if(decoded.eq.msg0) then ngood=ngood+1 else if(irc.ge.0) nbad=nbad+1 endif ii=imsg if(nrpt.gt.1) ii=nn write(*,1020) ii,msg0,decoded,itype,msgtype,irc 1020 format(i4,1x,a22,2x,a22,4x,i3,": ",a13,i3) enddo if(nmsg.eq.1 .and.nrpt.eq.1) then write(*,1030) dgen 1030 format(/'Packed message, 6-bit symbols ',12i3) !Display packed symbols write(*,1040) sent 1040 format(/'Information-carrying channel symbols'/(i5,20i3)) write(*,1050) dec 1050 format(/'Received message, 6-bit symbols ',12i3) !Display packed symbols endif enddo if(nrpt.gt.1) then write(*,1060) ngood,nrpt,nbad 1060 format('Decoded messages:',i5,'/',i4,' Undetected errors:',i5) endif 999 end program QRA64code