Read ephemeris data from a file and process it
Reads both one-line NAVSPASUR data and two-line NORAD data from an input file. The NAVSPASUR data is written to an update file, and the NORAD data is used in calculations to create an input data string for the Antenna Control Unit (ACU).
The input file "s4865r" is read and processed. The correct ephemeris data file is updated and parameters are calculated for the ACU. An output file " s4865rout.prt" will be generated. The output file contains input NORAD parameters (satellite data for calculating ACU values), output orbital parameters, and a data string to be sent to the ACU. Output to file "s4865rout" will be generated only for the NOAA-12 satellite.
SATRACK reads both one-line NAVSPASUR data and two-line NORAD data from an input file. The NAVSPASUR data is used to update files containing ephemeris data. If the information already exists within the appropriate file, the record is written to a duplicate entry file. These data files are located in ADAPSTABLES and have names based on their international satellite ID number (e.g., "16969.dat") except for the duplicate entry file "dupfile.dat".The NORAD data is used in calculations from which a data string of satellite information is created. This data string is used by the Antenna Control Unit (ACU) and contains values relating to the nodal period and the orbital radius. An output NORAD data file is also generated and sent to either a user-specified file, line printer, or terminal. The one-line NAVSPASUR input data is defined as follows:
Columns Description ------- ----------- 1 - 5 Satellite Number 6 - 10 Revolution Number 11 - 18 Mean Anomaly 19 - 26 Mean Motion 27 - 31 Decay 32 - 39 Eccentricity 40 - 47 Argument of Perigee 48 - 55 Longitude of Ascending Node 56 - 63 Inclination 64 - 69 Epoch (Year/Month/Day)The two-line NORAD input data is defined as follows:
Line 1 ------ Columns Description ------- ----------- 1 - 1 Line Number of Element Data 3 - 7 Satellite Number 10 - 11 International Designator (Last two digits of launch year) 12 - 14 International Designator (Launch number of the year) 15 - 17 International Designator (Piece of launch) 19 - 20 Epoch Year (Last two digits of year) 21 - 32 Epoch (Julian Day and fractional portion of the day) 34 - 43 First Time Derivative of the Mean Motion or Ballistic Coefficient (Depending on ephemeris type) 45 - 52 Second Time Derivative of Mean Motion (Blank if N/A) 54 - 61 BSTAR drag term if GP4 general perturbation theory was used. Otherwise, radiation pressure coefficient. 63 - 63 Ephemeris type 65 - 68 Element number 69 - 69 Check Sum (Modulo 10) (Letters, blanks, periods = 0; minus sign = 1; plus sign = 2)
Line 2 ------ Columns Description ------- ----------- 1 - 1 Line Number of Element Data 3 - 7 Satellite Number 9 - 16 Inclination [Degrees] 18 - 25 Right Ascension of the Ascending Node [Degrees] 27 - 33 Eccentricity (decimal point assumed) 35 - 42 Argument of Perigee [Degrees] 44 - 51 Mean Anomaly [Degrees] 53 - 63 Mean Motion [Revs per day] 64 - 68 Revolution number at epoch [Revs] 69 - 69 Check Sum (Modulo 10) All other columns are blank or fixed.
A duplicate record was found in the ephemeris data file; the duplicate record will be written to "dupfile.dat" in ADAPSTABLES.
A fatal error was encountered; processing is terminated. A more descriptive message was displayed immediately preceding this message.
Check the permissions of the path and file that is to be opened.
The user-specified input file could not be opened. Check the specified file, as well as its permissions.
An error was encountered while trying to read the input file. Check the permissions of the input file.
Check the permissions of the path and file in which the seeking is being attempted.
Check the permissions of the path and file in which the writing is being attempted.
The specified file does not exist or does not have the proper file permissions set.