WhereSat Application

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Description

This application uses input ephemeris to compute the predicted location of a satellite. The Earth-centered, Earth-fixed (ECEF) position of the satellite is reported. Optionally, the topocentric coordinates--azimuth, elevation, and range--can be generated. The user can specify the time interval between successive predictions. Also the output can generated in a format easily imported into numerical packages.

Command Summary

Required Arguments:

Short Arg.	Long Arg.	Description
-e	--eph-files=<arg>	Ephemeris source file(s). Can be RINEX navigation, SP3, or FIC.

Optional Arguments:

Short Arg.	Long Arg.	Description
-h	--help	Print help usage.
-u	--position=<arg>	Antenna position in ECEF (x,y,z) coordinates. Format as string "X Y Z", used to give user-centered data (SV range, azimuth, and elevation) when SV is in view.
	--start=<TIME>	Ignore data before this time. Format as string: "MO/DD/YYYY HH:MM:SS".
	--end=<TIME>	Ignore data after this time. Format as string: "MO/DD/YYYY HH:MM:SS".
-f	--time-format=<arg>	CommonTime format specifier used for times in the output. The default is "%4Y, %3j, %02H, %02M:%4.1f".
-p	--prn=<num>	Which SVs to analyze. Repeat option for multiple satellites. If this option is not specified, all ephemeris data will be processed.
-t	--time=<num>	Time increment in seconds for ephemeris calculation. Default is 900 seconds (15 minutes).

Examples

> WhereSat -b aira1720.06n -p 2 -u "918129.01 -4346070.45 803.18"
  -s "06/21/2006 17:00:00" -e "06/21/2006 20:00:00" -t 1800

 Antenna Position:  918129  -4.34607e+06  803.18
 Navigation File:   aira1720.06n
 Start Time:        06/21/2006 17:00:00
 End Time:          06/21/2006 20:00:00
 PRN:               2

 Prn 2 Earth-fixed position and clock information:

 Date       Time(UTC)   X (meters)          Y (meters)          Z (meters)      
 ===============================================================================
 06/21/2006 18:00:00  12758891.971859      18901201.616227      -14049016.596144
 06/21/2006 18:30:00  12847888.097031      21541501.416411      -9315422.851798 
 06/21/2006 19:00:00  12843576.989405      23087218.618683      -3957280.515764 
 06/21/2006 19:30:00  12450313.769289      23516935.034029      1667186.089065  

  . . .

    Clock Correc (s)
==================
     0.000007
     0.000007
     0.000007
     0.000007

 

 Data for user reference frame:

 Date       Time(UTC)   Azimuth        Elevation      Range to SV (m)
 =====================================================================
 06/21/2006 18:00:00  130.596202      -43.242769      29627531.177821
 06/21/2006 18:30:00  118.680085      -49.681012      29983796.522429
 06/21/2006 19:00:00  102.845663      -53.888528      30169796.433699
 06/21/2006 19:30:00  84.400419       -55.459042      30197072.648367

 Calculated 4 increments for prn 2 .

-- NicoleQuindara - 05 Aug 2011