320 research outputs found
Advanced Synthetic Aperture Radar Based on Digital Beamforming and Waveform Diversity
This paper introduces innovative SAR system
concepts for the acquisition of high resolution radar images with
wide swath coverage from spaceborne platforms. The new concepts
rely on the combination of advanced multi-channel SAR front-end
architectures with novel operational modes. The architectures
differ regarding their implementation complexity and it is shown
that even a low number of channels is already well suited to
significantly improve the imaging performance and to overcome
fundamental limitations inherent to classical SAR systems. The
more advanced concepts employ a multidimensional encoding of
the transmitted waveforms to further improve the performance
and to enable a new class of hybrid SAR imaging modes that are
well suited to satisfy hitherto incompatible user requirements for
frequent monitoring and detailed mapping. Implementation
specific issues will be discussed and examples demonstrate the
potential of the new techniques for different remote sensing
applications
SIGNAL: A Ka-band Digital Beam-Forming SAR System Concept to Monitor Topography Variations of Ice Caps and Glaciers
This paper discusses the implementation of an endto-
end simulator for the BIOMASS mission. An overview of
the system architecture is provided along with a functional
description of the modules that comprise the simulator
Ultra Wide Swath Imaging With Multi-Channel SAR Systems
Multi-channel radar systems allow for overcoming the inherent limitation of conventional synthetic aperture radar (SAR). An example is the combination of digital beamforming on receive in elevation with multi-aperture SAR signal reconstruction in azimuth which enables high-resolution wide-swath. As a next step, focus is turned to advanced concepts for the imaging of even wider swaths with high azimuth resolution. In this regard, the paper investigates the operation of multi-channel SAR systems in burst modes like ScanSAR or TOPS-SAR and analyses aspects of applying the multi-aperture reconstruction algorithm in combination with burst mode operation. The impact of the digital processing network on the SNR and the azimuth ambiguity-to-signal-ratio in multi-channel burst mode systems are considered and embedded in the design example of a ScanSAR system that enables the imaging of a 400 km wide swath with a geometric resolution of 5
Performance Investigation on Scan-On-Receive and Adaptive Digital Beam-Forming for High-Resolution Wide-Swath Synthetic Aperture Radar
The work investigates the performance of the Smart Multi-Aperture Radar Technique (SMART) Synthetic Aperture Radar (SAR) system for high-resolution wide-swath imaging based on Scan-on-Receive (SCORE) algorithm for receive beam steering. SCORE algorithm works under model mismatch conditions in presence of topographic height. A study on the potentiality of an adaptive approach for receive beam steering based on spatial spectral estimation is presented. The impact of topographic height on SCORE performance in different operational scenarios is examined, with reference to a realistic SAR system. The SCORE performance is compared to that of the adaptive approach by using the CramĂšr Rao lower bound analysis
Advanced Concepts for Ultra-Wide-Swath SAR Imaging
This paper reviews advanced multi-channel SAR system
concepts for the imaging of ultra-wide swaths with high azimuth
resolution. Novel system architectures and operational
modes are introduced and compared to each other with regard
to their performance
A Versatile Processing Chain for Experimental TanDEM-X Product Evaluation
TanDEM-X is a high-resolution interferometric mission with the main goal of providing a global digital elevation model
(DEM) of the Earth surface by means of single-pass X-band SAR interferometry. It is, moreover, the first genuinely
bistatic spaceborne SAR mission, and, independently of its usual quasi-monostatic configuration, includes many of the
peculiarities of bistatic SAR. An experimental, versatile, and flexible interferometric chain has been developed at DLR
Microwaves and Radar Institute for the scientific exploitation of TanDEM-X data acquired in non-standard configurations.
The paper describes the structure of the processing chain and focusses on some essential aspects of its bistatic part
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