Merged master 8748
This commit is contained in:
File diff suppressed because it is too large
Load Diff
@@ -1,377 +0,0 @@
|
||||
subroutine osd174(llr,apmask,ndeep,decoded,cw,nhardmin,dmin)
|
||||
!
|
||||
! An ordered-statistics decoder for the (174,87) code.
|
||||
!
|
||||
include "ldpc_174_87_params.f90"
|
||||
|
||||
integer*1 apmask(N),apmaskr(N)
|
||||
integer*1 gen(K,N)
|
||||
integer*1 genmrb(K,N),g2(N,K)
|
||||
integer*1 temp(K),m0(K),me(K),mi(K),misub(K),e2sub(N-K),e2(N-K),ui(N-K)
|
||||
integer*1 r2pat(N-K)
|
||||
integer indices(N),nxor(N)
|
||||
integer*1 cw(N),ce(N),c0(N),hdec(N)
|
||||
integer*1 decoded(K)
|
||||
integer indx(N)
|
||||
real llr(N),rx(N),absrx(N)
|
||||
logical first,reset
|
||||
data first/.true./
|
||||
save first,gen
|
||||
|
||||
if( first ) then ! fill the generator matrix
|
||||
gen=0
|
||||
do i=1,M
|
||||
do j=1,22
|
||||
read(g(i)(j:j),"(Z1)") istr
|
||||
do jj=1, 4
|
||||
irow=(j-1)*4+jj
|
||||
if( btest(istr,4-jj) ) gen(irow,i)=1
|
||||
enddo
|
||||
enddo
|
||||
enddo
|
||||
do irow=1,K
|
||||
gen(irow,M+irow)=1
|
||||
enddo
|
||||
first=.false.
|
||||
endif
|
||||
|
||||
! Re-order received vector to place systematic msg bits at the end.
|
||||
rx=llr(colorder+1)
|
||||
apmaskr=apmask(colorder+1)
|
||||
|
||||
! Hard decisions on the received word.
|
||||
hdec=0
|
||||
where(rx .ge. 0) hdec=1
|
||||
|
||||
! Use magnitude of received symbols as a measure of reliability.
|
||||
absrx=abs(rx)
|
||||
call indexx(absrx,N,indx)
|
||||
|
||||
! Re-order the columns of the generator matrix in order of decreasing reliability.
|
||||
do i=1,N
|
||||
genmrb(1:K,i)=gen(1:K,indx(N+1-i))
|
||||
indices(i)=indx(N+1-i)
|
||||
enddo
|
||||
|
||||
! Do gaussian elimination to create a generator matrix with the most reliable
|
||||
! received bits in positions 1:K in order of decreasing reliability (more or less).
|
||||
do id=1,K ! diagonal element indices
|
||||
do icol=id,K+20 ! The 20 is ad hoc - beware
|
||||
iflag=0
|
||||
if( genmrb(id,icol) .eq. 1 ) then
|
||||
iflag=1
|
||||
if( icol .ne. id ) then ! reorder column
|
||||
temp(1:K)=genmrb(1:K,id)
|
||||
genmrb(1:K,id)=genmrb(1:K,icol)
|
||||
genmrb(1:K,icol)=temp(1:K)
|
||||
itmp=indices(id)
|
||||
indices(id)=indices(icol)
|
||||
indices(icol)=itmp
|
||||
endif
|
||||
do ii=1,K
|
||||
if( ii .ne. id .and. genmrb(ii,id) .eq. 1 ) then
|
||||
genmrb(ii,1:N)=ieor(genmrb(ii,1:N),genmrb(id,1:N))
|
||||
endif
|
||||
enddo
|
||||
exit
|
||||
endif
|
||||
enddo
|
||||
enddo
|
||||
|
||||
g2=transpose(genmrb)
|
||||
|
||||
! 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.
|
||||
! Flip various combinations of bits in m0 and re-encode to generate a list of
|
||||
! codewords. Return the member of the list that has the smallest Euclidean
|
||||
! distance to the received word.
|
||||
|
||||
hdec=hdec(indices) ! hard decisions from received symbols
|
||||
m0=hdec(1:K) ! zero'th order message
|
||||
absrx=absrx(indices)
|
||||
rx=rx(indices)
|
||||
apmaskr=apmaskr(indices)
|
||||
|
||||
call mrbencode(m0,c0,g2,N,K)
|
||||
nxor=ieor(c0,hdec)
|
||||
nhardmin=sum(nxor)
|
||||
dmin=sum(nxor*absrx)
|
||||
|
||||
cw=c0
|
||||
ntotal=0
|
||||
nrejected=0
|
||||
|
||||
if(ndeep.eq.0) goto 998 ! norder=0
|
||||
if(ndeep.gt.5) ndeep=5
|
||||
if( ndeep.eq. 1) then
|
||||
nord=1
|
||||
npre1=0
|
||||
npre2=0
|
||||
nt=40
|
||||
ntheta=12
|
||||
elseif(ndeep.eq.2) then
|
||||
nord=1
|
||||
npre1=1
|
||||
npre2=0
|
||||
nt=40
|
||||
ntheta=12
|
||||
elseif(ndeep.eq.3) then
|
||||
nord=1
|
||||
npre1=1
|
||||
npre2=1
|
||||
nt=40
|
||||
ntheta=12
|
||||
ntau=14
|
||||
elseif(ndeep.eq.4) then
|
||||
nord=2
|
||||
npre1=1
|
||||
npre2=0
|
||||
nt=40
|
||||
ntheta=12
|
||||
ntau=19
|
||||
elseif(ndeep.eq.5) then
|
||||
nord=2
|
||||
npre1=1
|
||||
npre2=1
|
||||
nt=40
|
||||
ntheta=12
|
||||
ntau=19
|
||||
endif
|
||||
|
||||
do iorder=1,nord
|
||||
if( iorder.eq. 1 ) then
|
||||
misub(1:K-1)=0
|
||||
misub(K)=1
|
||||
iflag=K
|
||||
elseif( iorder.eq. 2 ) then
|
||||
misub(1:K-2)=0
|
||||
misub(K-1:K)=1
|
||||
iflag=K-1
|
||||
endif
|
||||
do while(iflag .ge.0)
|
||||
if(iorder.eq.nord .and. npre1.eq.0) then
|
||||
iend=iflag
|
||||
else
|
||||
iend=1
|
||||
endif
|
||||
do n1=iflag,iend,-1
|
||||
mi=misub
|
||||
mi(n1)=1
|
||||
if(any(iand(apmaskr(1:K),mi).eq.1)) cycle
|
||||
ntotal=ntotal+1
|
||||
me=ieor(m0,mi)
|
||||
if(n1.eq.iflag) then
|
||||
call mrbencode(me,ce,g2,N,K)
|
||||
e2sub=ieor(ce(K+1:N),hdec(K+1:N))
|
||||
e2=e2sub
|
||||
nd1Kpt=sum(e2sub(1:nt))+1
|
||||
d1=sum(ieor(me(1:K),hdec(1:K))*absrx(1:K))
|
||||
else
|
||||
e2=ieor(e2sub,g2(K+1:N,n1))
|
||||
nd1Kpt=sum(e2(1:nt))+2
|
||||
endif
|
||||
if(nd1Kpt .le. ntheta) then
|
||||
call mrbencode(me,ce,g2,N,K)
|
||||
nxor=ieor(ce,hdec)
|
||||
if(n1.eq.iflag) then
|
||||
dd=d1+sum(e2sub*absrx(K+1:N))
|
||||
else
|
||||
dd=d1+ieor(ce(n1),hdec(n1))*absrx(n1)+sum(e2*absrx(K+1:N))
|
||||
endif
|
||||
if( dd .lt. dmin ) then
|
||||
dmin=dd
|
||||
cw=ce
|
||||
nhardmin=sum(nxor)
|
||||
nd1Kptbest=nd1Kpt
|
||||
endif
|
||||
else
|
||||
nrejected=nrejected+1
|
||||
endif
|
||||
enddo
|
||||
! Get the next test error pattern, iflag will go negative
|
||||
! when the last pattern with weight iorder has been generated.
|
||||
call nextpat(misub,k,iorder,iflag)
|
||||
enddo
|
||||
enddo
|
||||
|
||||
if(npre2.eq.1) then
|
||||
reset=.true.
|
||||
ntotal=0
|
||||
do i1=K,1,-1
|
||||
do i2=i1-1,1,-1
|
||||
ntotal=ntotal+1
|
||||
mi=ieor(g2(K+1:K+ntau,i1),g2(K+1:K+ntau,i2))
|
||||
call boxit(reset,mi(1:ntau),ntau,ntotal,i1,i2)
|
||||
enddo
|
||||
enddo
|
||||
|
||||
ncount2=0
|
||||
ntotal2=0
|
||||
reset=.true.
|
||||
! Now run through again and do the second pre-processing rule
|
||||
if(nord.eq.1) then
|
||||
misub(1:K-1)=0
|
||||
misub(K)=1
|
||||
iflag=K
|
||||
elseif(nord.eq.2) then
|
||||
misub(1:K-1)=0
|
||||
misub(K-1:K)=1
|
||||
iflag=K-1
|
||||
endif
|
||||
do while(iflag .ge.0)
|
||||
me=ieor(m0,misub)
|
||||
call mrbencode(me,ce,g2,N,K)
|
||||
e2sub=ieor(ce(K+1:N),hdec(K+1:N))
|
||||
do i2=0,ntau
|
||||
ntotal2=ntotal2+1
|
||||
ui=0
|
||||
if(i2.gt.0) ui(i2)=1
|
||||
r2pat=ieor(e2sub,ui)
|
||||
778 continue
|
||||
call fetchit(reset,r2pat(1:ntau),ntau,in1,in2)
|
||||
if(in1.gt.0.and.in2.gt.0) then
|
||||
ncount2=ncount2+1
|
||||
mi=misub
|
||||
mi(in1)=1
|
||||
mi(in2)=1
|
||||
if(sum(mi).lt.nord+npre1+npre2.or.any(iand(apmaskr(1:K),mi).eq.1)) cycle
|
||||
me=ieor(m0,mi)
|
||||
call mrbencode(me,ce,g2,N,K)
|
||||
nxor=ieor(ce,hdec)
|
||||
dd=sum(nxor*absrx)
|
||||
if( dd .lt. dmin ) then
|
||||
dmin=dd
|
||||
cw=ce
|
||||
nhardmin=sum(nxor)
|
||||
endif
|
||||
goto 778
|
||||
endif
|
||||
enddo
|
||||
call nextpat(misub,K,nord,iflag)
|
||||
enddo
|
||||
endif
|
||||
|
||||
998 continue
|
||||
! Re-order the codeword to place message bits at the end.
|
||||
cw(indices)=cw
|
||||
hdec(indices)=hdec
|
||||
decoded=cw(K+1:N)
|
||||
cw(colorder+1)=cw ! put the codeword back into received-word order
|
||||
return
|
||||
end subroutine osd174
|
||||
|
||||
subroutine mrbencode(me,codeword,g2,N,K)
|
||||
integer*1 me(K),codeword(N),g2(N,K)
|
||||
! fast encoding for low-weight test patterns
|
||||
codeword=0
|
||||
do i=1,K
|
||||
if( me(i) .eq. 1 ) then
|
||||
codeword=ieor(codeword,g2(1:N,i))
|
||||
endif
|
||||
enddo
|
||||
return
|
||||
end subroutine mrbencode
|
||||
|
||||
subroutine nextpat(mi,k,iorder,iflag)
|
||||
integer*1 mi(k),ms(k)
|
||||
! generate the next test error pattern
|
||||
ind=-1
|
||||
do i=1,k-1
|
||||
if( mi(i).eq.0 .and. mi(i+1).eq.1) ind=i
|
||||
enddo
|
||||
if( ind .lt. 0 ) then ! no more patterns of this order
|
||||
iflag=ind
|
||||
return
|
||||
endif
|
||||
ms=0
|
||||
ms(1:ind-1)=mi(1:ind-1)
|
||||
ms(ind)=1
|
||||
ms(ind+1)=0
|
||||
if( ind+1 .lt. k ) then
|
||||
nz=iorder-sum(ms)
|
||||
ms(k-nz+1:k)=1
|
||||
endif
|
||||
mi=ms
|
||||
do i=1,k ! iflag will point to the lowest-index 1 in mi
|
||||
if(mi(i).eq.1) then
|
||||
iflag=i
|
||||
exit
|
||||
endif
|
||||
enddo
|
||||
return
|
||||
end subroutine nextpat
|
||||
|
||||
subroutine boxit(reset,e2,ntau,npindex,i1,i2)
|
||||
integer*1 e2(1:ntau)
|
||||
integer indexes(4000,2),fp(0:525000),np(4000)
|
||||
logical reset
|
||||
common/boxes/indexes,fp,np
|
||||
|
||||
if(reset) then
|
||||
patterns=-1
|
||||
fp=-1
|
||||
np=-1
|
||||
sc=-1
|
||||
indexes=-1
|
||||
reset=.false.
|
||||
endif
|
||||
|
||||
indexes(npindex,1)=i1
|
||||
indexes(npindex,2)=i2
|
||||
ipat=0
|
||||
do i=1,ntau
|
||||
if(e2(i).eq.1) then
|
||||
ipat=ipat+ishft(1,ntau-i)
|
||||
endif
|
||||
enddo
|
||||
|
||||
ip=fp(ipat) ! see what's currently stored in fp(ipat)
|
||||
if(ip.eq.-1) then
|
||||
fp(ipat)=npindex
|
||||
else
|
||||
do while (np(ip).ne.-1)
|
||||
ip=np(ip)
|
||||
enddo
|
||||
np(ip)=npindex
|
||||
endif
|
||||
return
|
||||
end subroutine boxit
|
||||
|
||||
subroutine fetchit(reset,e2,ntau,i1,i2)
|
||||
integer indexes(4000,2),fp(0:525000),np(4000)
|
||||
integer lastpat
|
||||
integer*1 e2(ntau)
|
||||
logical reset
|
||||
common/boxes/indexes,fp,np
|
||||
save lastpat,inext
|
||||
|
||||
if(reset) then
|
||||
lastpat=-1
|
||||
reset=.false.
|
||||
endif
|
||||
|
||||
ipat=0
|
||||
do i=1,ntau
|
||||
if(e2(i).eq.1) then
|
||||
ipat=ipat+ishft(1,ntau-i)
|
||||
endif
|
||||
enddo
|
||||
index=fp(ipat)
|
||||
|
||||
if(lastpat.ne.ipat .and. index.gt.0) then ! return first set of indices
|
||||
i1=indexes(index,1)
|
||||
i2=indexes(index,2)
|
||||
inext=np(index)
|
||||
elseif(lastpat.eq.ipat .and. inext.gt.0) then
|
||||
i1=indexes(inext,1)
|
||||
i2=indexes(inext,2)
|
||||
inext=np(inext)
|
||||
else
|
||||
i1=-1
|
||||
i2=-1
|
||||
inext=-1
|
||||
endif
|
||||
lastpat=ipat
|
||||
return
|
||||
end subroutine fetchit
|
||||
|
||||
@@ -0,0 +1,93 @@
|
||||
For this step and the next, you may want to pretend you are K1JT
|
||||
by entering that callsign temporarily as *My Call* on the
|
||||
*Settings | General* tab. Your results should then be identical to
|
||||
those shown in the screen shot below.
|
||||
|
||||
.Open a Wave File:
|
||||
|
||||
- Select *File | Open* and select the file
|
||||
+...\save\samples\JT9\130418_1742.wav+. When the file opens you should
|
||||
see something similar to the following screen shot:
|
||||
|
||||
[[X12]]
|
||||
image::main-ui.png[align="center",alt="Main UI and Wide Graph"]
|
||||
|
||||
.Decoding Overview
|
||||
|
||||
Decoding takes place at the end of a receive sequence and proceeds in
|
||||
two steps. The first decode is done at the selected Rx frequency,
|
||||
indicated by the U-shaped green marker on the waterfall frequency
|
||||
scale. Results appear in both the left (*Band Activity*) and right
|
||||
(*Rx Frequency*) text windows on the main screen. The program then
|
||||
finds and decodes all signals in the selected mode over the displayed
|
||||
frequency range. The red marker on the waterfall scale indicates your
|
||||
Tx frequency.
|
||||
|
||||
Seven JT9 signals are present in the example file, all decodable.
|
||||
When this file was recorded KF4RWA was finishing a QSO with K1JT.
|
||||
Since the green marker was placed at his audio frequency, 1224 Hz, his
|
||||
message `K1JT KF4RWA 73` is decoded first and appears in the *Rx
|
||||
Frequency* window. The *Band Activity* window shows this message plus
|
||||
all decodes at other frequencies. By default lines containing `CQ`
|
||||
are highlighted in green, and lines with *My Call* (in this case K1JT)
|
||||
in red.
|
||||
|
||||
[[X13]]
|
||||
.Decoding Controls
|
||||
|
||||
To gain some feeling for controls frequently used when making QSOs,
|
||||
try clicking with the mouse on the decoded text lines and on the
|
||||
waterfall spectral display. You should be able to confirm the
|
||||
following behavior:
|
||||
|
||||
- Click or double-click on either of the decoded lines highlighted in
|
||||
green. These actions produce the following results:
|
||||
|
||||
** Callsign and locator of a station calling CQ are copied to the *DX
|
||||
Call* and *DX Grid* entry fields.
|
||||
|
||||
** Messages are generated for a standard minimal QSO.
|
||||
|
||||
** The *Tx even* box is checked or cleared appropriately, so that you
|
||||
will transmit in the proper (odd or even) minutes.
|
||||
|
||||
** The Rx frequency marker is moved to the frequency of the CQing
|
||||
station.
|
||||
|
||||
** The *Gen Msg* ("`generated message`") radio button at bottom right
|
||||
of the main window is selected.
|
||||
|
||||
** *Double-click* does all of the above and also activates *Enable Tx*
|
||||
so that a transmission will start automatically at the proper time.
|
||||
|
||||
** You can modify the double-click behavior by holding down the
|
||||
*Shift* key to move only the Tx frequency or the *Ctrl* key to move
|
||||
both Rx and Tx frequencies.
|
||||
|
||||
NOTE: You can prevent your Tx frequency from being changed by checking the
|
||||
box *Hold Tx Freq*.
|
||||
|
||||
- Double-click on the decoded message `K1JT N5KDV EM41`, highlighted
|
||||
in red. Results will be similar to those in the previous step. The Tx
|
||||
frequency (red marker) is not moved unless *Shift* or *Ctrl* is held
|
||||
down. Messages highlighted in red are usually in response to your own
|
||||
CQ or from a tail-ender, and you probably want your Tx frequency to
|
||||
stay where it was.
|
||||
|
||||
- Click somewhere on the waterfall to set Rx frequency (green marker
|
||||
on waterfall scale).
|
||||
|
||||
- Shift-click on the waterfall to set Tx frequency (red marker).
|
||||
|
||||
- Ctrl-click on the waterfall to set both Rx and Tx frequencies.
|
||||
|
||||
- Double-click on a signal in the waterfall to set Rx frequency and
|
||||
start a narrow-band decode there. Decoded text will appear in the
|
||||
right window only.
|
||||
|
||||
- Ctrl-double-click on a signal to set both Rx and Tx frequencies and
|
||||
decode at the new frequency.
|
||||
|
||||
- Click *Erase* to clear the right window.
|
||||
|
||||
- Double-click *Erase* to clear both text windows.
|
||||
Reference in New Issue
Block a user