MIMO SAR FORMATIONS: ORBITAL DIAMETER AND SYNCHRONIZATION TOLERANCES
- 1Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Pzza Leonardo da Vinci, 32, 20133 Milano, Italy
- 2Aresys srl, via Flumendosa 16, 20132 Milano, Italy
- 3Dipartimento di Ingegneria Elettrica e dell'Informazione, Politecnico di Bari, Via E. Orabona, 4, 70126 Bari, Italy
Keywords: SAR, MIMO Radar, Interferometry, Tomography, Radar imaging
Abstract. Multiple-Input-Multiple Output (MIMO) Synthetic Aperture Radar (SAR) along-track formations can be used to fraction the power resources into compact, lightweight and cost-effective satellites, or to extend the swath coverage beyond the limit provided by a small antenna. In this second case, the Pulse Repetition Frequency (PRF) is kept low by implementing an inversion that solves up to N−1 ambiguities, given N observations. The simultaneous illumination – that allows for the N² gain due to the coherent combination of the N transmitters and the N receivers, is analyzed and shown not to be critical, as the more than N=2 sensors are assumed. Performance is evaluated for the N=2 and N=3 cases and compared with the Single Input Multiple Output formations, where one sensor is transmitting, and all are receiving. Finally, the impact of the across-track deviation from the orbit is modeled and evaluated.