User's Guide

TBUS

Converts and writes TBUS satellite tracking information file to a standard ephemeris data structure.

Function:

Reads in a Tiros Bulletin United States (TBUS) satellite tracking information file and converts the data to a standard ephemeris data structure. The standard ephemeris data structure consists of a sixty-nine character line containing the satellite ID, orbit number, mean anomaly, mean motion, orbital decay, eccentricity, argument of perigee, longitude of ascending node, inclination, and the date of epoch. This line of data is placed in a file named <XXX>;DAT in the ADAPSTABLES directory where <XXX> is the satellite ID. Equatorial crossing information can be calculated and printed to a user specified device.

Parameters:

INFILE
Input file name. The user-specified file that contains the TBUS satellite tracking information. This file is obtained daily from the NOAA Information Center Bulletin Board. The default extension is ";BUS".

SATID
Satellite IDs. The satellite IDs that the user wants to process. The default will be to process all current satellite tracking information.

   = N09:  15427 NOAA-09
   = N10:  16969 NOAA-10
   = N11:  19531 NOAA-11
   = N12:  21263 NOAA-12
   = N14:  23455 NOAA-14
   = N15:  25338 NOAA-15
   = N16:  26536 NOAA-16
   = N17:  27453 NOAA-17
   = N18:  28654 NOAA-18
   = N19:  33591 NOAA-19
   = M02:  29499 METOP-2

PRINT(--)
Output destination. This output contains the equatorial crossing, the time of ascending node, and the orbit number for each of the orbits.

  = NONE:      No report.  The equatorial crossing
               report will not be generated.
  = TERM:      Terminal.  Output is sent to the
               user's terminal.
  = LP:        Line printer.  Output is sent to the
               printer defined by $PRINTER.
  = Filename:  User-supplied filename.  Output is
               sent to the user-supplied file with
               the extension ";PRT".

Examples:

  1. LAS> tbus infile=s4941001_0509;data

    The TBUS file, s4941001_0509;DATA, will be read with every satellite tracking information header in the file being converted to the standard ephemeris data structure. Each ephemeris line of data will be written to the file with that particular file's satellite ID and ";DAT" as its extension.

  2. LAS> tbus infile=s4941201 satid=n11 print=eq11.dat

    The TBUS file, s4941201;BUS, will be read with only the tracking information from the satellite NOAA 11 being converted to the standard ephemeris data structure. The satellite ID of the NOAA 11 satellite is 19531, so each of the ephemeris lines of data will be written to the file, "19531;DAT" in the ADAPSTABLES directory. A report that contains equatorial crossing information for the satellite will be computed and written to the "EQ11.DAT;PRT" file.

  3. LAS> tbus infile=tbus2 print=term

    The TBUS file, TBUS2;BUS, will be read and the tracking information from the satellites NOAA 9, NOAA 10, NOAA 11, and NOAA 12 satellite will be converted to the standard ephemeris data structure. Each of the ephemeris lines of data will be written to the appropriate file designated by its satellite ID and the extension ";DAT". The equatorial crossing report will be created for the specified satellite and displayed to the user's terminal.

Description/Algorithm:

A TBUS satellite tracking information file is read and the appropriate information is extracted and converted to a standard ephemeris data structure. The TBUS information uses the key "APT PREDICT" to determine the start of the valid TBUS information. All values are loaded into a sixty-nine character ephemeris data line that is appended to the file designated by the satellite ID of the particular file and the extension ";DAT". The TBUS satellite tracking information file is not deleted. For each satellite specified, equatorial crossing information can be calculated and printed to a device specified by the user.

Nonfatal Error Messages:

  1. [tbus-close] Error closing file <XXXXX>

    An error occurred while trying to close the specific file.

  2. [tbus-none] No TBUS information found

    There was no TBUS information found in the specified input file. Respecify the input TBUS file name or check that the file contains the "APT PREDICT" key in the file.

Fatal Error Messages:

  1. [tbus-fatal] Fatal error encountered

    A fatal error occurred during processing. A description of the specific error precedes this message.

  2. [tbus-open] Error opening file <XXXXX>

    An error occurred because the specific file could not be opened. Check the protections on the file and make sure the file exists.

  3. [tbus-readfile] Error reading the TBUS file

    An error occurred while trying to read the specified file.

  4. [tbus-getenv] Error getting environment variable ADAPSTABLES

    An error occurred while retrieving the ADAPSTABLES path. Make sure that the ADAPSTABLES environment variable is set.

  5. [tbus-setephem] Error setting ephemeris structure

    The ephemeris structure could not be set from the TBUS information. Check to insure that the TBUS information is valid.

User Notes:

  1. Converting TBUS satellite tracking information to a standard ephemeris data structure requires certain values to be backed up from epoch time (time the TBUS information was gathered) to 12:00 midnight in Greenwich, England (GMT).

  2. The TBUS file must contain the "APT PREDICT" key to determine the start of the valid TBUS information.

  3. A program associated with TBUS is NAVSPASUR.