dopplerTrack(1)           User Commands           dopplerTrack(1)



NAME
     dopplerTrack - Set synthesizers to doppler track a source

SYNOPSIS
     Executables live in /application/bin on hal


DESCRIPTION
     "dopplerTrack" is a program which  configures  the  MRG  and
     DDSs  to  doppler  track  a source.   It fetches the current
     coordinates,  and  performs  the  required  calculations  to
     center a spectral feature in the desired portion of the IF.

     Doppler tracking is handled in a somewhat  complicated  way.
     The  MRG  is programmed to the frequency required to exactly
     doppler correct the Array Reference Position when the source
     is  transiting.    Therefore,  the  MRG is always set to the
     same frequency regardless of when the  dopplerTrack  command
     is  issued  (on a particular day).   The diurnal motion, and
     the portion of the earth orbital motion  that  differs  from
     the  value  at  source transit, are handled by adjusting the
     DDS frequencies.   Also fringe stopping, which is equivalent
     to  the difference in doppler frequencies between the anten-
     nas and the Array Reference Position, is handled by  adjust-
     ing  the DDSs.  This division on doppler correction may seem
     strange, but it's dictated by the fact  that  the  MRG  fre-
     quency  cannot be adjusted rapidly, whereas the DDS frequen-
     cies can and must be.   On the other hand, the limited  fre-
     quency  range of the DDSs precludes doing the entire doppler
     correction with the DDS hardware.

ARGUMENTS
     <filename>
          This is the name of the output file of the JAVA  corre-
          lator  configuration program.   USE OF THIS FILE IS NOT
          YET IMPLEMENTED.

OPTIONS
     -b<num>
          Center the line in the block specified by <num>,  where
          <num> is an integer between 1 and 6.   This switch must
          be used with -c.   It cannot be used with -t.

     -c<num>
          Center the line in the chunk specified by <num>,  where
          <num> is an integer between 1 and 4.   This switch must
          be used with -b.   It cannot be used with -t.

     -d    Print debugging messages

     -f<dbl>
          Offset the line by <dbl> GHz, where <dbl> is  a  double



SunOS 5.5           Last change: 1999 Apr. 2                    1






dopplerTrack(1)           User Commands           dopplerTrack(1)



          precision float.

     -r<dbl>
          Use <dbl> as the rest frequency in GHz of the  line  to
          be doppler tracked.  <dbl> is a double precision float.
          The default is 230.53797 { CO(2-1) }.

     -t    Center the spectral  line  in  the  Timoc  correlator.
          Because  the  bandwidth of the Timoc correlator differs
          from a standard SMA spectral "chunk", this switch  does
          not  result  in the spectral line being centered in any
          particular chunk.

     -v<dbl>
          Use <dbl> as a velocity offset for the  spectral  line.
          <dbl>  is  a  double precision float, and the units are
          km/sec.


KNOWN BUGS
     This program has never been tested on the sky!


RESPONSIBLE
     Raoul Taco Machilvich
     rtm@dolson.harvard.edu
     617 495-7330
     617 873-0877



























SunOS 5.5           Last change: 1999 Apr. 2                    2