Center of Box Predictions

It is normal for satellites to move due to gravitational and other perturbations associated with the Earth, sun, and moon. Satellite customers use Center of Box (COB) predictions to determine the best time to orient their earth station antennae to ensure peak performance. COB charts reference an imaginary box positioned at the center of the satellite orbital position. Since the satellite is required to stay within a ±0.05 latitude/longitude box, the center of box is defined by a smaller, concentric ±0.01 latitude/longitude box. X-band users should align ground station antennas >3.0m in diameter when the satellite is passing through the center of box. (Within ~ +/- 30 minutes)

There are two important ways to use this data:

1. For larger antennae, the user can look up the date of the smallest deviation to provide the best time to adjust for strongest performance across a range of days.

2. Or, if a user is planning to adjust on a certain day, they can use the table to find the time of day when the satellite is nearest to COB.

Fill out the form below to request XTAR-LANT Center of Box Predictions.