SAR processing without a motion measurement system
Paper in proceedings, 2017

This paper leads a discussion on how to form a SAR image without knowing the track. That is within the scope of Factorized Geometrical Autofocus (FGA). The FGA algorithm is a base-2 fast factorized back-projection formulation with six free geometry parameters (per sub-aperture pair). These are tuned step-by-step until a sharp image is obtained. This innovative autofocus technique can compensate completely for an erroneous geometry. The FGA algorithm has been applied successfully on two UWB data sets, acquired by the CARABAS II system at VHF-band. The tracks are known (measured accurately). We however adopt and modify a basic geometry model. A linear equidistant track at fixed altitude is initially assumed. Apart from deviations due to linearization, a ~2.5 m/s along-track velocity error is also introduced. Resulting FGA images are compared to reference images and verified to be focused. This indicates that it is feasible to form a SAR image without support from a motion measurement system.

Author

Jan Torgrimsson

Microwave and Optical Remote Sensing

Patrik Dammert

Hans Hellsten

Lars Ulander

Microwave and Optical Remote Sensing

Proceedings of EURAD

1-4

Areas of Advance

Information and Communication Technology

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

Signal Processing

DOI

10.23919/EURAD.2017.8249132

ISBN

978-2-87487-049-1

More information

Latest update

12/28/2018