A Simplified Method to Approximate the AOI Coverage Duration in Single Acquisition Direction for SAR Satellites with Repeat Ground-Track Orbits

Abstract

In early stages of SAR mission design the coverage capabilities of a system are either tailored to fulfil the mission objectives or drive their development. Traditionally, this involves using complex software that evaluates the intersections of an Area of Interest (AOI) with the footprint of the SAR instrument throughout the orbit using a grid-point approach. Although this methodology yields precise results, it requires cumbersome software setups and scenario configurations in order to achieve a complete representation of the system's coverage performance. To address this challenge, this paper proposes a simplified methodology based on the geometric relations between the instrument's swath width, the ascending orbital ground-tracks, and the potential positions of an AOI. By adopting this approach, streamlined analysis of the minimum and maximum access possibilities for various AOIs, or different system and orbit configurations becomes feasible. Consequently, an approximate representation of the system's coverage capabilities can be obtained straightforwardly.