The focus of this paper is on the exploitation of COSMO-SkyMed spotlight SAR images for Ground Moving Target Indication (GMTI). To this purpose, a two-step processing chain is proposed: the first step performs stationary clutter removal, whereas the second step performs moving targets detection. Both the steps are based on the use of a bank of focusing filters, each one matched to a different relative speed between the radar antenna and the target, here implemented as Chirp Scaling Algorithms in order to keep low the computational burden. The performance of the proposed technique is investigated by applying it to COSMO-SkyMed Single Look Complex spotlight SAR images and compared to theoretical performance: the analysis shows the effectiveness of the proposed technique in suppressing the stationary clutter and providing a high gain in signal to background power ratio, thus allowing subclutter visibility despite the single-channel nature of COSMO-SkyMed data. Moreover, the information provided by the bank is used to estimate the target motion and, by using a knowledge-based approach, relocate in along-track direction the detected movers. The shown results prove the feasibility of a GMTI mode for the COSMO-SkyMed SAR system and more in general for single-channel spaceborne systems.

Multichannel space-based synthetic aperture radar (SAR) systems that exploit receiving antenna subarrays displaced in the along-track direction have been shown to provide the capability to detect ground moving targets and potentially estimate their radial motion velocity, thus making possible their correct relocation inside the SAR image of the background. However, the use of only two receiving channels to contain cost, mass, and data-rate, imposes limitations in terms of potentiality of joint clutter cancelation and target velocity estimation. To overcome this problem, we propose a full MIMO SAR scheme obtained by transmitting nearly orthogonal waveforms with the two subarrays achieved from a single antenna aperture and receiving with the same subarrays. A complete processing chain for the joint detection, imaging, and radial speed estimation is presented showing that by properly applying the clutter cancelation step before waveform compression, a good clutter removal performance is obtained despite the waveforms are not fully orthogonal. The performance of the proposed MIMO system is deeply investigated and compared to the performance of conventional multichannel systems to assess the relative merits and drawbacks.

The focus of the paper is on the exploitation of COSMO-SkyMed (CSK) spotlight SAR images for Ground Moving Target Indication (GMTI). To this purpose two moving target detection schemes are considered: the first is based on a bank of Chirp Scaling Algorithms (CSAs), each one matched to a different relative speed between the radar antenna and the target, and the second is based on Change Detection (CD) applied to sub-images obtained by splitting the overall aperture into sub-apertures. The application of the techniques to Single Look Complex (SLC) CSK spotlight SAR images shows the feasibility of a GMTI mode able to extract medium/high radar cross section moving targets even for single channel spaceborne systems. © 2011 IEEE

Within the European project SOS ("Sensors system for detection and tracking of dangerous materials in order to increase the airport security in indoor landside area") new solutions for airports' security are being studied by several European universities and industries. In particular, a collaborative effort is devoted to the development of an imaging mode for the airports' perimeter surveillance, the results of which will be preliminarily shown in this paper. An X-band frequency modulated continuous wave (FMCW) radar for a ISAR imaging mode in the context of an ATR (automatic target recognition) system will be described, and the results of the preliminary tests conducted in a real environment with cooperative targets will be reported and analyzed.

The paper proposes a Passive Multistatic ISAR mode (PM-ISAR) for coastal surveillance based on the exploitation of multiple transmitting satellites and a single receiver (with multiple receiving channels). A proper processing technique able to focus the single bistatic images of the ship target of interest, to align them to the same reference plane and to properly combine them is introduced. The use of multiple transmitters allows a proper integration of the information concerning the different scattering centers of the target when observed by different bistatic pairs. Thus the resulting multistatic ISAR image could be very useful for ATR (Automatic Target Recognition) purposes