scholarly journals BUILDINGS IN HIGH RESOLUTION SAR IMAGES - IDENTIFICATION BASED ON CITYGML DATA

2015 ◽  
Vol II-3/W4 ◽  
pp. 9-16 ◽  
Author(s):  
S. Auer ◽  
A. Donaubauer
Keyword(s):  
High Resolution ◽  
City Center ◽  
Sar Images ◽  
Data Format ◽  
Building Geometry ◽  
First Results ◽  
Automated Processing ◽  
Urban Scene ◽  
System Data ◽  
Sar Imagery

Motivated by the distinct appearance of facades in high resolution SAR images with respect to signal incidence angles and polarizations, this paper introduces a way to fuse SAR imagery and 3D GIS (geoinformation system) data (format: CityGML) based on SAR simulation methods. To this end, the known building geometry is used to simulate the extent of building layover for identifying the related image parts in high resolution TerraSAR-X images. The simulated SAR images are generated and geocoded by an automated processing chain which is initialized by the automated parsing of the CityGML dataset and the TerraSAR-X orbit file. Confirming the functionality of the developed interface between simulation and CityGML, first results are presented for an urban scene in the Munich city center in order to discuss future opportunities in the context of change detection applications.

scholarly journals X-Band/C-Band-Comparison of Ship Wake Detectability

2020 ◽  
Author(s):  
Björn Tings ◽  
Sven Jacobsen ◽  
Stefan Wiehle ◽  
Egbert Schwarz ◽  
Holger Daedelow
Keyword(s):  
Detection Performance ◽  
Automatic Identification ◽  
Identification System ◽  
Sar Images ◽  
Ship Wake ◽  
X Band ◽  
System Data ◽  
Wake Detection ◽  
Sar Imagery ◽  
The Individual

Recent studies investigated the detectability of ship wake signatures on SAR imagery using a large number of SAR images collocated with Automatic Identification System data for training machine learning models. These detectability models are in agreement with oceanographic expectations from preceding studies and can therefore be used for comparing the performance of different SAR sensors in terms of wake detectability. Previous model comparisons showed better wake detection performance of TerraSAR-X (TS-X) than of RADARSAT-2 (RS2) and Sentinel-1 (S1). A comparison between CosmoSkymed (CSK) and RS2 is performed here, to examine the hypothesis that X-Band is generally better for wake detection than C-Band. Finally, this hypothesis is not confirmed, as the detectability models for TS-X, CSK and RS2 reveal similar performances. A comparison of wake detection performance should take the individual wake components into account separately.

scholarly journals UPGRADE OF FOSS DATE PLUG-IN: IMPLEMENTATION OF A NEW RADARGRAMMETRIC DSM GENERATION CAPABILITY

2016 ◽  
Vol XLI-B7 ◽  
pp. 821-825 ◽  
Author(s):  
M. Di Rita ◽  
A. Nascetti ◽  
F. Fratarcangeli ◽  
M. Crespi
Keyword(s):  
High Resolution ◽  
Open Source ◽  
Open Source Software ◽  
Weather Conditions ◽  
Ground Sample ◽  
Satellite Systems ◽  
Stereo Reconstruction ◽  
First Results ◽  
Sar Imagery ◽  
University Of Rome

Synthetic Aperture Radar (SAR) satellite systems may give important contribution in terms of Digital Surface Models (DSMs) generation considering their complete independence from logistic constraints on the ground and weather conditions. In recent years, the new availability of very high resolution SAR data (up to 20 cm Ground Sample Distance) gave a new impulse to radargrammetry and allowed new applications and developments. Besides, to date, among the software aimed to radargrammetric applications only few show as free and open source. It is in this context that it has been decided to widen DATE (Digital Automatic Terrain Extractor) plug-in capabilities and additionally include the possibility to use SAR imagery for DSM stereo reconstruction (i.e. radargrammetry), besides to the optical workflow already developed. <br><br> DATE is a Free and Open Source Software (FOSS) developed at the Geodesy and Geomatics Division, University of Rome “La Sapienza”, and conceived as an OSSIM (Open Source Software Image Map) plug-in. It has been developed starting from May 2014 in the framework of 2014 Google Summer of Code, having as early purpose a fully automatic DSMs generation from high resolution optical satellite imagery acquired by the most common sensors. <br><br> Here, the results achieved through this new capability applied to two stacks (one ascending and one descending) of three TerraSAR-X images each, acquired over Trento (Northern Italy) testfield, are presented. Global accuracies achieved are around 6 metres. These first results are promising and further analysis are expected for a more complete assessment of DATE application to SAR imagery.

Sub-urban landscape characterization by very high-resolution X-band COSMO-Skymed SAR images: first results

2010 ◽  
Author(s):  
Fabio Del Frate ◽  
Domenico Loschiavo ◽  
Chiara Pratola ◽  
Giovanni Schiavon ◽  
Domenico Solimini
Keyword(s):  
High Resolution ◽  
Urban Landscape ◽  
Sar Images ◽  
Landscape Characterization ◽  
X Band ◽  
First Results ◽  
Very High

scholarly journals REPEAT-PASS INTERFEROMETRIC AND BACKSCATTER ANALYSIS OF X-BAND PAZ SATELLITE – FIRST RESULTS

2020 ◽  
Vol XLIII-B3-2020 ◽  
pp. 253-258
Author(s):  
S. Abdikan ◽  
C. Bayik ◽  
M. Ustuner ◽  
F. Balik Sanli
Keyword(s):  
High Resolution ◽  
Sand Dunes ◽  
Ground Surface ◽  
Central Anatolia ◽  
X Band ◽  
First Results ◽  
Multi Temporal ◽  
Sar Imagery ◽  
Single Polarization ◽  
New Generation

Abstract. In this paper we present the initial results of PAZ Synthetic Aperture Radar (SAR) imagery for the first time. In the study, the potential of repeat-pass high resolution PAZ images were investigated. To this aim, both linear backscatter and interferometric results were presented. We used multi-temporal X-band (3.1 cm wavelength) new generation single look complex (SLC) data from Spanish PAZ in single polarization data. PAZ is based on TerraSAR-X/TanDEM-X platform to establish a constellation with them to shorten the revisit time and increase data acquisition capacity. We applied two analysis on PAZ data to assess the performance of the satellite images. For the analysis a semi-arid and almost flat region of Central Anatolia was selected. The images are acquired in both ascending and descending orbits. Each pair has 33 days of temporal baselines. Firstly, backscatter analysis was conducted over the region for different land cover classes. Secondly interferometric analysis was applied to determine phase difference and coherence features. As the region has sand dunes, bareland and uncultivated agricultural fields the coherence analysis showed high values, while cultivated fields showed variations of coherence due to different growth of vegetation. Since the region is prone to sinkhole formation the high-resolution PAZ indicated its advantage as determining a sinkhole that has a circle shape. The displacement of ground surface is determined in line of sight direction.

scholarly journals UPGRADE OF FOSS DATE PLUG-IN: IMPLEMENTATION OF A NEW RADARGRAMMETRIC DSM GENERATION CAPABILITY

2016 ◽  
Vol XLI-B7 ◽  
pp. 821-825
Author(s):  
M. Di Rita ◽  
A. Nascetti ◽  
F. Fratarcangeli ◽  
M. Crespi
Keyword(s):  
High Resolution ◽  
Open Source ◽  
Open Source Software ◽  
Weather Conditions ◽  
Ground Sample ◽  
Satellite Systems ◽  
Stereo Reconstruction ◽  
First Results ◽  
Sar Imagery ◽  
University Of Rome

Synthetic Aperture Radar (SAR) satellite systems may give important contribution in terms of Digital Surface Models (DSMs) generation considering their complete independence from logistic constraints on the ground and weather conditions. In recent years, the new availability of very high resolution SAR data (up to 20 cm Ground Sample Distance) gave a new impulse to radargrammetry and allowed new applications and developments. Besides, to date, among the software aimed to radargrammetric applications only few show as free and open source. It is in this context that it has been decided to widen DATE (Digital Automatic Terrain Extractor) plug-in capabilities and additionally include the possibility to use SAR imagery for DSM stereo reconstruction (i.e. radargrammetry), besides to the optical workflow already developed. <br><br> DATE is a Free and Open Source Software (FOSS) developed at the Geodesy and Geomatics Division, University of Rome “La Sapienza”, and conceived as an OSSIM (Open Source Software Image Map) plug-in. It has been developed starting from May 2014 in the framework of 2014 Google Summer of Code, having as early purpose a fully automatic DSMs generation from high resolution optical satellite imagery acquired by the most common sensors. <br><br> Here, the results achieved through this new capability applied to two stacks (one ascending and one descending) of three TerraSAR-X images each, acquired over Trento (Northern Italy) testfield, are presented. Global accuracies achieved are around 6 metres. These first results are promising and further analysis are expected for a more complete assessment of DATE application to SAR imagery.

scholarly journals CHALLENGES AND POTENTIALS USING MULTI ASPECT COVERAGE OF URBAN SCENES BY AIRBORNE SAR ON CIRCULAR TRAJECTORIES

2015 ◽  
Vol XL-3/W2 ◽  
pp. 149-154 ◽  
Author(s):  
S. Palm ◽  
N. Pohl ◽  
U. Stilla
Keyword(s):  
Sar Images ◽  
Image Stack ◽  
Urban Scenes ◽  
Aspect Angle ◽  
Highly Nonlinear ◽  
First Results ◽  
Urban Scene ◽  
Airborne Sar ◽  
Entire Trajectory ◽  
Sar Processing

Airborne SAR on small and flexible platforms guarantees the evaluation of local damages after natural disasters and is both weather and daylight independent. The processing of circular flight trajectories can further improve the reconstruction of target scenes especially in complex urban scenarios as shadowing and foreshortening effects can be reduced by multiple views from different aspect angles (hyper- or full- aspect). A dataset collected with the Miranda 35 GHz radar system with 1 GHz bandwidth on a small ultralight aircraft on a circular trajectory over an urban scene was processed using a time domain approach. The SAR processing chain and the effects of the navigational data for such highly nonlinear trajectories and unstable platforms are described. The generated SAR image stack over the entire trajectory consists of 240 individual SAR images, each image visualizing the scene from a slightly different aspect angle. First results for the fusion of multiple aspect views to create one resulting image with reduced shadow areas and the possibility to find hidden targets are demonstrated. Further potentials of such particular datasets like moving target indication are discussed.

Development of Building Height Data in Peru from High-Resolution SAR Imagery

2014 ◽  
Vol 9 (6) ◽  
pp. 1042-1049 ◽  
Author(s):  
Wen Liu ◽  
◽  
Fumio Yamazaki ◽  
Bruno Adriano ◽  
Erick Mas ◽  
...  
Keyword(s):  
High Resolution ◽  
Satellite Image ◽  
Ground Surface ◽  
Sar Images ◽  
Building Height ◽  
Radar Sensors ◽  
Gis Data ◽  
Building Footprint ◽  
Image Displays ◽  
Sar Imagery

Building data, such as footprint and height, are important information for pre- and post-event damage assessments when natural disasters occur. However, these data are not easily available in many countries. Because of the remarkable improvements in radar sensors, high-resolution (HR) Synthetic Aperture Radar (SAR) images can provide detailed ground surface information. Thus, it is possible to observe a single building using HR SAR images. In this study, a new method is developed to detect building heights automatically from two-dimensional (2D) geographic information system (GIS) data and a single HR TerraSAR-X (TSX) intensity image. A building in a TSX image displays a layover from the actual position to the direction of the sensor, because of the side-looking nature of the SAR. Since the length of the layover on a ground-range SAR image is proportional to the building height, it can be used to estimate this height. We shift the building footprint obtained from 2D GIS data toward the sensor direction. The proposed method was applied to a TSX image of Lima, Peru in the HighSpot mode with a resolution of about 1 m. The results were compared with field survey photos and an optical satellite image, and a reasonable level of accuracy was achieved.

scholarly journals Urban Riverway Extraction from High-Resolution SAR Image Based on Blocking Segmentation and Discontinuity Connection

2020 ◽  
Vol 12 (24) ◽  
pp. 4014
Author(s):  
Yu Li ◽  
Yun Yang ◽  
Quanhua Zhao
Keyword(s):  
High Resolution ◽  
Signal To Noise Ratio ◽  
Bottom Layer ◽  
Speckle Reduction ◽  
Image Block ◽  
Sar Images ◽  
The Difference ◽  
Sar Imagery ◽  
Layer Region ◽  
Region Growth

An urban riverway extraction method is proposed for high-resolution synthetic aperture radar (SAR) images. First, the original image is partitioned into overlapping sub-image blocks, in which the sub-image blocks that do not cover riverways are regarded as background. Sub-image blocks covering riverways are then filtered using the iterative adaptive speckle reduction anisotropic diffusion (SRAD) that introduces the relative signal-to-noise ratio (RSNR). The filtered images are segmented quickly by the Sauvola algorithm, and the false riverway fragments are removed by the area and aspect ratio of the connected component in the segmentation results. Using the minimum convex hull of each riverway segment as the connection object, the seeds are automatically determined by the difference between adjacent pyramid layers, and the sub-image block riverway extraction result is used as the bottom layer. The discontinuity connection between river segments is achieved by multi-layer region growth. Finally, the processed sub-image blocks are stitched to get the riverway extraction results for the entire image. To verify the applicability and usefulness of the proposed approach, high-resolution SAR imagery obtained by the Gaofen-3 (GF-3) satellite was used in the assessment. The qualitative and quantitative evaluations of the experimental results show that the proposed method can effectively and completely extract complex urban riverways from high-resolution SAR images.

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