Simulation study on inclined orbit constellation of high-resolution electrooptical sensors for enhanced imaging efficiency in region of interest

Abstract

Traditionally, high-resolution electrooptical (EO) sensors are placed in Sun-synchronous orbits (SSO) as they enable consistent solar illumination during imaging and near-global coverage for various remote sensing applications. However, these sensors inherently offer limited swath coverage resulting in poorer imaging efficiency and often require a large number of satellites in constellation for improving revisit time over region of interest (RoI). Compared with constellation of satellites in SSO, a smaller number of satellites in lower inclination orbits can provide significant advantage in terms of imaging efficiency in the tropical and near-tropical RoIs, which is desirable for many civilian and strategic applications. In this work, detailed analytical simulations have been performed for inclined orbit constellation of high-resolution EO sensors, and higher imaging efficiency has been demonstrated against SSO constellation. Rigorous mathematical models are developed to enable optimization of constellation design with proper fine-tuning of orbital parameters to maximize imaging efficiency in the RoI, and the model output is validated through STK simulation. For quantitative evaluation of imaging efficiency, two figures of merits, namely, average number of access per day and number of days with no access, have been estimated for various design cases. This study shows significant improvements in imaging efficiency parameters up to a factor of 3 in RoI as compared with traditional SSO constellation. This study is generic in nature and is applicable for any inclination angles and latitudes in the tropical and near tropical RoIs. This study can significantly aid in design of satellite constellations for future remote sensing missions.