subroutine genmsk32(msg,msgsent,ichk,itone,itype) use hashing character*22 msg,msgsent,hashmsg character*4 crpt,rpt(0:63) logical first integer itone(144) integer ig32(0:65536-1) !Codewords for Golay (24,12) code integer*1 codeword(32),bitseq(32) integer*1 s8r(8) data s8r/1,0,1,1,0,0,0,1/ data first/.true./ save first,rpt,ig32 if(first) then call ldpc32_table(ig32) !Define the Golay(24,12) codewords do i=0,30 if( i.lt.5 ) then write(rpt(i),'(a1,i2.2,a1)') '-',abs(i-5) write(rpt(i+31),'(a2,i2.2,a1)') 'R-',abs(i-5) else write(rpt(i),'(a1,i2.2,a1)') '+',i-5 write(rpt(i+31),'(a2,i2.2,a1)') 'R+',i-5 endif enddo rpt(62)='RRR ' rpt(63)='73 ' first=.false. endif itype=-1 msgsent='*** bad message ***' itone=0 i1=index(msg,'>') if(i1.lt.9) go to 900 call fmtmsg(msg,iz) crpt=msg(i1+2:i1+5) do i=0,63 if(crpt.eq.rpt(i)) go to 10 enddo go to 900 10 irpt=i !Report index, 0-31 if(ichk.lt.10000) then hashmsg=msg(2:i1-1)//' '//crpt call hash(hashmsg,22,ihash) ihash=iand(ihash,1023) !10-bit hash ig=64*ihash + irpt !6-bit report else ig=ichk-10000 endif ncodeword=ig32(ig) ! write(*,*) 'codeword is: ',ncodeword,'message is: ',ig,'report index: ',irpt,'hash: ',ihash do i=1,32 codeword(i)=iand(1,ishft(ncodeword,1-i)) enddo bitseq=codeword bitseq=2*bitseq-1 ! Map I and Q to tones. itone=0 do i=1, 16 itone(2*i-1)=(bitseq(2*i)*bitseq(2*i-1)+1)/2; itone(2*i)=-(bitseq(2*i)*bitseq(mod(2*i,32)+1)-1)/2; enddo ! Flip polarity itone=-itone+1 msgsent=msg itype=7 900 return end subroutine genmsk32