A5069597533- Synthetic Aperture Radar (SAR) Applications and Techniques
- Advanced SAR Imaging Techniques
- Soil Moisture and Remote Sensing
- Radar Systems and Signal Processing
- Geophysical Methods and Applications
- Spacecraft Design and Technology
- Antenna Design and Optimization
- Geophysics and Gravity Measurements
- Radio Astronomy Observations and Technology
- Arctic and Antarctic ice dynamics
- Microwave Imaging and Scattering Analysis
- Planetary Science and Exploration
- Inertial Sensor and Navigation
- Spacecraft and Cryogenic Technologies
- Methane Hydrates and Related Phenomena
- Ocean Waves and Remote Sensing
- Space Satellite Systems and Control
- Satellite Communication Systems
- Infrared Target Detection Methodologies
- GNSS positioning and interference
- Advanced Data Compression Techniques
- Underwater Acoustics Research
- Sensor Technology and Measurement Systems
- Fault Detection and Control Systems
- Robotics and Sensor-Based Localization
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2014-2025
Radar (United States)
2009
Presents a generalized formulation of the extended chirp scaling (ECS) approach for high precision processing air- and spaceborne SAR data. Based on original function, ECS algorithm incorporates new azimuth function subaperture approach, which allow an effective phase-preserving ScanSAR data without interpolation geometric correction. The can also be used automatic coregistration interferometric image pairs are acquired with different sampling distances. Additionally, novel range is proposed...
This paper presents a new processing algorithm for spotlight SAR data processing. The performs the range cell migration correction non-chirped raw without interpolation by using novel frequency scaling operation. azimuth is based on spectral analysis approach which made highly accurate scaling. In almost all stages, subaperture introduced efficient this paper, complete derivation of presented. A very useful formulation signals in Doppler domain also proposed where residual video phase...
This paper presents an efficient phase preserving processor for the focusing of data acquired in sliding spotlight and Terrain Observation by Progressive Scans (TOPS) imaging modes. They share common a linear variation Doppler centroid along azimuth dimension, which is due to steering antenna (either mechanically or electronically) throughout take. Existing approaches processing can become inefficient additional overcome folding focused domain. In this paper, new scaling approach presented...
This paper addresses several important aspects that need to be considered for the processing of spaceborne synthetic aperture radar (SAR) data with resolutions in decimeter range. In particular, it will shown how motion satellite during transmission/reception chirp signal and effect troposphere deteriorate impulse response function if not properly considered. Further have been investigated include curved orbit, array pattern electronically steered antennas, considerations within itself. For...
This paper reports about the performed investigations for implementation of wide-swath TOPS (Terrain Observation by Progressive Scan) imaging mode with TerraSAR-X (TSX). The overcomes limitations imposed ScanSAR steering antenna along track during acquisition a burst. In this way, all targets are illuminated complete azimuth pattern, and, thus, scalloping is circumvented, and an dependence signal-to-noise ratio distributed target ambiguity (DTAR) avoided. However, use electronically steered...
The paper investigates the possibility to enhance TerraSAR-X (TSX) azimuth resolution by means of staring spotlight imaging in combination with an extended pattern steering. current TSX modes are briefly reviewed, and steering limitations discussed. Based on a realistic simulation performance estimation using Kepler orbit WGS84 reference ellipsoid, key parameters estimated for increasing angle span. ambiguity is identified be driving parameter. Experimental high-resolution images presented....
This letter presents a new method, called total Zero Doppler steering, to perform yaw and pitch steering for spaceborne synthetic aperture radar (SAR) systems. The method reduces the centroid theoretically 0 Hz, independent of range position interest. Residual errors are only due pointing inaccuracy or approximations in implementation zero law. compares with currently applied methods. attitude angles residual frequencies calculated depicted exemplarily parameters TerraSAR-X, which will be...
Spaceborne bistatic and multistatic SAR configurations are an attractive approach to acquire along-track cross-track interferograms on a global scale. An efficient realisation of such systems may be achieved by set low-cost, passive receivers onboard constellation microsatellites which simultaneously record the backscattered signals transmitted conventional spaceborne radar. The authors introduce several suitable for single-pass interferometry discuss their advantages limitations. achievable...
This paper describes the sliding spotlight algorithm and processing strategy to be applied for TerraSAR-X. The steering geometry is analysed. Analysis of scene size resolution demonstrates particularities this mode. Doppler frequencies individual targets a whole are analyzed result shows applicabil- ity azimuth subaperture data. A description Extended Chirp Scaling Algorithm presented.
This Paper provides a demonstrative derivation of the effect up and down chirp modulation on point extended target signals. Analysis has been performed with respect to signal amplitude, extension, rate phase behavior. The suppression "point target" range ambiguities is investigated for possible TerraSAR-X parameter setting. Extended targets have simulated filtered. A Range-Ambiguity Simulator under development which based airborne X-band data from Experimental SAR (E-SAR) DLR. simulator...
This Paper describes the newly introduced Dual Re- ceive Antenna Mode (DRA) of TerraSAR-X instrument. It explains principle forming two receiving antennas and deals with already identified new applications experi- ments enabled by this mode, e.g. along track interferometry, geometric resolution enhancement full polarimetric mode.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> This paper presents results from the synthetic aperture radar (SAR) system performance characterization, optimization, and verification as carried out during TerraSAR-X commissioning phase. Starting acquisition geometry instrument performance, fundamental parameters such elevation beam definition, range timing, receiving gain, block adaptive quantization setting are presented. The of key...
This paper introduces the bidirectional synthetic aperture radar (BiDi SAR) imaging mode, i.e., simultaneous of two directions by one antenna into receiving channel, and presents short-term time series images interferograms acquired TerraSAR-X TanDEM-X satellites. A comparison to alternative approaches for acquisition is provided. The BiDi geometry defined, a pattern analyzed. raw data are simulated, sampled with different pulse repetition frequency values, compared real data. spectral...
This paper introduces the concept of a fractionated MirrorSAR which is based on set mutually separated transmitter and receiver satellites. As opposed to previously published bi- multistatic SAR systems, satellites are considerably simplified, as their main functionality reduced kind microwave mirror (or space transponder) routes radar echoes towards transmitter. The forwarded signals then coherently demodulated within by using same oscillator that had been used for pulse generation. avoids...
This article reports the Phase A study results of interferometric extension high-resolution wide-swath (HRWS) mission with three MirrorSAR satellites. According to concept, small, low-cost, transponder-like receive-only satellites without radar signal demodulation, digitization, memory storage, downlink, and synchronization are added planned German X-band HRWS mission. The fly a triple helix orbit in close formation around span multiple single-pass baselines. comprehensive system engineering...
TerraSAR-X is a satellite that scheduled to be launched in October 2006 and currently being built the framework of public–private partnership between German Aerospace Centre (DLR) EADS Astrium GmbH Germany will carry an X-band synthetic aperture radar (SAR) instrument equipped with active phased array antenna. Its operational flexibility allow use for scientific commercial applications. High amplitude phase stability achieved by carbon fibre reinforced plastic slotted waveguide radiator high...
This paper addresses several innovative steps needed in the chirp scaling and extended (ECS) algorithms order to process staring Spotlight TerraSAR-X (TSX) images with 21 cm azimuth resolution 300 MHz range bandwidth. The aspects that need of special consideration are 2D phase truncation frequency domain ECS, element pattern antenna array, curved orbit, stop-and-go approximation, troposphere. All these expounded detail a solution is given for each them. suggested corrections applied at raw...
The effects of strong motion errors in wide-beam azimuth synthetic aperture radar (SAR) processing are analysed and discussed, using simulated data, as well data collected by the airborne experimental SAR system Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) (E-SAR). A new sub-aperture approach for residual error compensation is proposed.
For the TerraSAR-X mission, a new staring spotlight mode has been implemented delivering very high azimuth resolution. Detailed performance analyses have conducted to optimize commanding parameters for this mode. Compared previously available imaging modes, requires operating instrument with minimum margins and at edge of specifications, radar designed for. Therefore, an additional step-a global acquisition simulation analysis-is introduced during operationalization ensure suitability...
The satellite of the TerraSAR-X mission, called TSX, was launched on 15 June 2007 and its identically constructed twin TDX, which is required by mission TanDEM-X, 21 2010. Together they supply high-quality radar data in order to serve two goals: Scientific observation Earth provisioning remote sensing for commercial market (TerraSAR-X mission) generation a global digital elevation model (DEM) Earth’s surface (TanDEM-X mission). On occasion 10th anniversary focus will be development system...