Preparing for the test:

Creating the ephemeris file

• I'm storing the info in /share/obs4/usr/radar/r3399/
  
• tle's were download from celestrak
  
• I've used the 19297.429  tle's
• tle.191027
• MOLNIYA 2-9
  1 07276U 74026A   19297.42981504  .00000029  00000-0  67986-3 0  9992
  2 07276  63.7779  20.5574 6843309 289.0551  12.3182  2.45095432225650
  
• tle.191028
• MOLNIYA 3-10
  1 11057U 78095A   19297.80922998  .00001337  00000-0  18064-3 0  9994
  2 11057  62.6564  50.5084 5979996 293.4621  16.1522  4.08988723344139
• The tle files should be named:
• tle.yymmdd    (since mkephm.sc uses the date to select the tle file).
  
• The routine mkephm.sc will generate an ao radar ephemeris from the tle's
• edit mkephm.sc
  
• date=191027
• tmSt=1330
• tmEnd=1530
• date:yymmdd, tmSt=hhmm (start time), tmEnd=hhmm (end time)
• where dates and times are utc.. don't enter leading 0's in the times
• ./mkephm.sc   . this will
  
• send to tle file to horizons telnet interface
• download the  ephemeris quantities:  2 (app ra,dec) ,4(apparent az,el), 20(range and rangerate)
• run hortoao.pl to convert from horizons to ao short format
• run ephmaotordr to convert from ao short format to ao radar
• The radar ephm will have the rx info equal to the tx info
• looking at the round trip time and the az,el change per second this can introduce a pointing error of about 1"
• the doppler will be set to 0.
• Links to radar ephemeris files that were used
• .297 used the 19297 tle files
• .299 used the 19299 tle files
  
• ephm_191027.rdr.297
• ephm_191028.rdr.299
  

Checking the az,za rates

    Using the ephemeris file, i plotted up the positions and rates of the satellites for each day

molniya position and rates for 27/28oct19 (.ps) (.pdf)

• Page 1-2 27oct19 molniya 2-9
• Page 3-4 28oct19 molniya 3-10
• FirstPage: az,za
  
• top: az,za  track. rise is on the right
• This plots the feed azimuth (180 degrees from the source azimuth)
  
• middle: az rate vs hour of day
• the dashed red lines are the slew rates in azimuth
  
• bottom: za velocity vs hour of day
• the dashed red lines are the slew rates
• 2nd page: ra,dec,rtt, sat velocity
• top is the apparent ra,dec track for the object.
• middle: round trip time (from, to  AO) in millisecs
• bottom: satellite radial velocity (km/sec) with negative approaching AO.

The difference between the 297,299 tle files:

    The tle files were  downloaded from celestrack.

• 27oct19 tracking:
• the tle file was dated 19297 (24oct19)
  
• It was downloaded friday 25oct19.
  
• a 19299 tle file was  available on 26oct19 (but was not used).

The plots show the position differences for ephemerides made from the two tle files (.ps) (.pdf)

•  ephem299 - ephm297 is plotted
• Top: little circle az (black), za(red)  differences vs azimuth (source az)
• middle: great circle difference
• The max value is about 4 arc seconds.
  
• bottom :great circle difference vs hour (utc)
  

Summary:

•  the positions only change be about 4 asecs between the two dates
  

Performing the experiment

  We will probably start out with cw to make sure the other stations see a signal

•  rise/set times (utc)
  
• 27oct19 : 14:16:00  to 15:25:30
  
• 28oct19 : 15:34:00  to 16:08:00

Transmitted power
    The plot shows the transmitted power vs hour of day for 27,28oct19 (.ps) (.pdf)

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