Attitude profiles for ground-path pointing and alignment of radar footprints: Application to the INCUS mission

This work presents the derivation of pointing profiles for a satellite mission requiring continuous observations of a ground path. The study is directly applied to the INvestigation of Convective Updrafts (INCUS) mission, a three-satellite constellation designed to investigate tropical convective storms through time-differenced radar observations. A sequence of pitch, roll, and yaw rotations was investigated to align each spacecraft with the reference ground path, while accounting for mission-specific requirements and constraints. A pointing strategy with fixed pitch and time-varying roll was examined to achieve ground-path pointing. A subsequent yaw rotation was then studied to ensure correct cross-track alignment of the radar footprints. A numerical search-strategy was performed to derive the time difference between observations and the pointing profiles, while an additional analytical formulation was also developed to address the footprint alignment problem. The effects of in-track spacecraft knowledge position errors on both the pointing profiles and cross-track alignment of the footprints were also investigated. Moreover, the effects of variations in orbital inclination and altitude on the pointing profiles have been addressed