Task detailed definition Pierfrancesco Lombardo Rome, October 13, 2004 Overview of activities Task detailed definition Euclid 9.17 Pierfrancesco Lombardo

Concept of Phased Array SAR with ECCM and GMTI P. Lombardo - Euclid 9.17

Focus of the study This study will focus on the adaptive beam-forming for SAR ECCM Target disturbance is wide-band noise-like jammer that can be counteracted by using phased array Desired result is to be able to form high resolution SAR images of desired ground areas, despite the presence of jamming sources P. Lombardo - Euclid 9.17

Study Plan Specific issues under consideration: Task 1: Task 2: Optimal Phased Array structure for SAR ECCM Wide-band ECCM techniques for SAR Task 2: Performance analysis of SAR with Wide-band ECCM System-level requirements for Wide-band ECCM P. Lombardo - Euclid 9.17

Optimal Phased Array structure for SAR ECCM (I) ECCM capability can be largely affected by sub-array structure Target is to find compromise solutions for planar phase array, that yield good jammer cancellation performance with a limited number of channels Comparison of planar phased array (with sub-arrays) ws. Reflector antenna with multi-feed in terms of ECCM performance P. Lombardo - Euclid 9.17

Optimal Phased Array structure for SAR ECCM (II) For planar active phased array: Selection of optimal sub-array structure Irregular Overlapping Regular “Beams” DBF ABF SLC Comparison with reflector antenna with multi-feed P. Lombardo - Euclid 9.17

Wide-band ECCM techniques for SAR (I) SAR require very wide transmitted frequency bandwidths The simple approach of a weighted sum of the samples collected at a single time on the different channels (snapshot) is expected to be largely inadequate ECCM techniques appropriate for wide-band should be devised P. Lombardo - Euclid 9.17

Wide-band ECCM techniques for SAR (II) Transversal Filter Can Provide Beamforming Weights and Time Delay P. Lombardo - Euclid 9.17

Wide-band ECCM techniques for SAR (III) Wideband Digital Time Delay could also be used adaptively (to be investigated) P. Lombardo - Euclid 9.17

Performance analysis of SAR with Wide-band ECCM Evaluation of effectiveness in jammer cancellation (reduction of jamming power obtained by the devised ECCM technique): - Improvement Factor vs jamming azimuth & elevation - Blind angle/ground area reduction with ECCM Evaluation of potential degradation in SAR image quality (ideal in the absence of jammer) caused by the presence of the ECCM technique: - degradation of the SAR Impulse Response Function in relation to jamming azimuth & elevation The analysis will be carried out for some different sub-array structures of the planar array and for the reflector antenna with multi-feed P. Lombardo - Euclid 9.17

System-level requirements for Wide-band ECCM A/D requirements for wide-band SAR ECCM - required number of bit - I&Q inbalance Channel mismatch requirements for wide-band SAR ECCM - channel transfer function difference - channels total path equalization requirements - potential digital equalization P. Lombardo - Euclid 9.17