Investigation of Fixed Across-Track Baselines for Distributed Spaceborne SAR Systems

Abstract:
Spaceborne Synthetic Aperture Radar (SAR) greatly benefits from distributed concepts. This work investigates the opportunity of establishing formations with fixed baselines. In particular, a fixed baseline in the across-track direction can enhance the performance of SAR interferometry for the generation of accurate digital elevation models or enable multiplatform range ambiguity suppression. Achieving a fixed across-track baseline requires a continuous forced solution of the relative motion, different from the Helix configuration, adopted for TanDEM-X, which relies on a natural solution of the dynamics. This study aims to evaluate the feasibility of continuous control, in terms of δ-velocity budget, and the impact on SAR interferometric performance. The analyses yield promising results in terms of SAR applications and can be used for preliminary mission analysis and design, including both SAR and mission control considerations.