Influence of Time Intervals: Comparative Analysis of Short-Arc Orbit Determination for GEO Satellites Using AER and RNG Methods

Abstract

Short arc orbit determination for GEO satellites is useful when there are gaps or incomplete data due to limited time or other factors. Full cycle orbit determination requires continuous data over the entire orbit cycle, which may not always be available. This research assesses the accuracy of short arc orbit determination for GEO satellites for various time intervals ranging from 6-hour- to 42-hour intervals using two data collecting techniques: azimuth elevation range (AER) and range-to-range (RNG). Iterative Least-Squares Estimation, a numerically integrated method, is then used to determine the orbit, by either calculating new bias values or preexisting bias values. The results show that average root mean square error (RMSE) values are 0.792 km and 0.160 km for AER and RNG type observation data, respectively, using pre-existing bias values. On the other hand, using new bias calculation, the average RMSE values are 36.480 km and 6.254 km for AER and RNG. The findings indicate that the RNG method provides superior accuracy in determining the orbit for both satellites. The study recommends the use of pre-existing bias values over calculating new ones. Short arc orbit determination can provide a reasonable estimate of the satellite's orbit when a limited amount of data is available due to various reasons and can also be used to quickly assess and correct any deviations or errors in the satellite's orbit, improving overall accuracy and reliability.

Keywords

• short-arc orbit determination
• orbit
• bias value
• range method
• azimuth elevation range method