ephtest - estimates quality of orbital elements.

ephtest - Estimates quality of orbital elements.

SYNOPSIS

ephtest  [ parameter=value ... ]

Parameters are: satellite, pass_date, orb_elem_date.

DESCRIPTION

To estimate the quality of the orbital elements, the following actions are performed by ephtest:

a) Find the orbital elements for pass_date and use them to compute the reference satellite position for the interval from 00:00 GMT to 24:00 GMT for the same date.

b) Find the orbital elements for orb_elem_date and use them to compute the satellite position for the same interval as in a).

c) Compare these two data and print out the statistical information: along-track error (min,max), and absolute distance error (max,mean).

The $SATDATA/satel/<satellite_name>/orbdata file with orbital elements for a given satellite must exist.

PARAMETERS

satellite: This is the name of the satellite. There is no default.

pass_date: This is the pass date. The default pass_date is today. See formats for valid date formats.

orb_elem_date: This is the date of the orbital elements to analyze. The default orb_elem_date is the day previous to the pass_date. See formats for valid date formats.

EXAMPLES

[902] % ephtest
satellite      : char(  8) ? noaa-9
pass_date      : char( 15) ? [94/07/19]
orb_elem_date  : char( 15) ? [94/07/18]
along-track err (km): -0.25 .. 0.05
Eph. dates: 94/07/19, 94/07/18 : max: 0.3 km, mean: 0.1 km
[903] %

FILES

orbdata

NOTES

Last Update: $Date: 1998/05/28 18:04:59 $