• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.104-123
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• 2001

Synthetic Aperture Radar(SAR) can provide radar imagery in all weather, day and night situations. Recently SAR system consisted of several imaging modes, has been used for not only military purpose, but also commercial and scientific applications. This paper firstly reviews spaceborne SAR theory, specially scansar principle, and secondly the theories and the design procedures of system performance analysis in the scansar mode, which are different from the ones in the conventional stripmap mode. Based on the SAR-related knowledge, it lastly derives the results of performance analysis in wide swath mode using the scansar technique at the design phase. It shows that these results can meet the system requirements as given the customer. In future, they will continuously be updated using the real measurement data, in connection with the development of a spaceborne SAR system.

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.2
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• pp.101-120
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• 2000

A synthetic aperture radar (SAR) system can provide all-weather, day and night, superior imaging capability, and thus is very useful in surveillance for military applications. In this paper, a X-band spaceborne SAR system design concept is introduced with the key design parameters for mission and system requirements characterized by small satellite system. The SAR imaging mode design procedure is presented, and the standard imaging mode design results are analyzed as an example. In line with the given mission and system requirements, the X-band SAR payload and ground reception/processing subsystems are designed and presented with the key design results. The designed small satellite SAR system shows the wide range of imaging capability, and proves to be an effective surveillance system in light-weight, high-performance and cost-effective points of view.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.2
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• pp.160-169
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• 2007

In this paper, we have described and simulated the effect analysis and correction of phase errors in the SAR rawdata induced by satellite attitude errors such as drift, jitter. This simulation is based on the FSA(Frequency Scaling Algorithm) for high resolution image formation of the Spotlight SAR. Phase errors produce the degradation of SAR image quality such as loss of resolution, geometric distortion, loss of contrast, spurious targets, and decrease in SNR. To resolve this problem, this paper presents method for correction of phase errors using the PGA(Phase Gradient Algorithm) in connection with the FSA. Several results of the phase errors correction are presented for Spotlight SAR rawdata.

• Korean Journal of Remote Sensing
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• v.39 no.6_3
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• pp.1791-1799
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• 2023

The Korea Aerospace Research Institute is responsible for supplying and supporting the utilization of imagery data from the Arirang satellite series for organizations affiliated with the Government Satellite Information Application Consultation. Most of them primarily utilize optical imagery, and there is a relative lack of utilization of Synthetic Aperture Radar (SAR) imagery. In this paper, as part of supporting the use of SAR images, we investigated SAR intensity-based change detection algorithms and their use cases that have been researched to determine SAR intensity-based change detection algorithms to be developed in the future. As a result of the research, we found that various algorithms utilizing intensity difference, correlation coefficients, histograms, or polarimetric information have been researched by numerous researchers to detect and analyze change pixels and the applications of change detection algorithms have been studied in various fields such as a city, flood, forest fire, and vegetation. This study will serve as a reference for the development of SAR change detection algorithms, intended for utilization in the Government Satellite Information Application Consultation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.2
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• pp.147-156
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• 2005

SAR interferometry (InSAR) is a technique to generate 3-Dimentional spatial information using complex data pairs observed by antennas at different locations. In case of the Two-pass differential SAR inteferometry (DInSAR), the topographic phase signature can be separated from the contribution of surface deformation in the interferometric phase. In this study, InSAR and DInSAR were implemented with ERS- l/2 tandem pair to produce DEM. The accuracy of the Resulting DEMs was analyzed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.75-86
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• 2012

Synthetic Aperture Radar(SAR) imaging system is independent of solar illumination and weather conditions; however, SAR image is difficult to interpret as compared with optical images. It has been increased interest in multi-sensor fusion technique which can improve the interpretability of $SAR^{\circ\circ}$ images by fusing the spectral information from multispectral(MS) image. In this paper, a multi-sensor fusion method based on high-frequency extraction process using Fast Fourier Transform(FFT) and outlier elimination process is proposed, which maintain the spectral content of the original MS image while retaining the spatial detail of the high-resolution SAR image. We used TerraSAR-X which is constructed on the same X-band SAR system as KOMPSAT-5 and KOMPSAT-2 MS image as the test data set to evaluate the proposed method. In order to evaluate the efficiency of the proposed method, the fusion result was compared visually and quantitatively with the result obtained using existing fusion algorithms. The evaluation results showed that the proposed image fusion method achieved successful results in the fusion of SAR and MS image compared with the existing fusion algorithms.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.3
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• pp.453-460
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• 2010

For high quality image acquisition, compensating air-vehicle motion is essential for airborne SAR system. This paper describes a timing control based motion compensation method for airborne SAR system. Efficient timing control is critical for SAR system since it maintains many timing signals and timing setting for the signals should be updated frequently. This paper proposes Timing Cluster method as an efficient means for timing control of SAR system. Moreover, this paper suggests a simple and efficient method to compensate air-vehicle motion based on the Timing Cluster method. Timing Cluster method enables SAR system to control the timing in a timing noncritical way just maintaining little amount of information.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.221-227
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• 2006

The SAR evaluation system with 9 stationary probes inserted into the object to be surveyed can calculate area SAR value based on the 9 measured electric field data. The results can be acquired in a few seconds by converting obtained area SAR to the volume SAR. The system can be very useful tool in the stages of handset development for mobile communication as well as in the handset production line because of its rapid SAR measurement ability. The validity of the measurement system is checked by showing that the measured SAR values agree well with reference SAR values suggested in the reference documents.

• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.163-169
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• 2011

This paper introduces a method about water line detection using SAR image. The method includes pre-processing of the SAR image with the threshold of the histogram to recognize the boundary between the water and the landmass area. Finally we applied the image differentiation to detect the water line in the SAR image. The TerraSAR-X and the Cosmo-SkyMed images, which are the high spatial resolution X-band SAR data, are used for the evaluation of our algorithm. The accuracy is verified over the stream line in urban area with the result from the Cosmo-SkyMed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.7
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• pp.1258-1270
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• 2000

A synthetic aperture radar (SAR) system is able to provide all-weather, day-and-night, high resolution imaging capability in the wide area of interest, and thus is extremely useful in surveillance for both civil and military applications. In this paper, the X-band high-resolution spaceborne SAR system design is described with the key design parameters for the mission and system requirement characterized by the small satellite platform. The SAR imaging mode design technique is presented, and the standard imaging mode design results are analyzed with respect to image quality performance. In line with the system requirement, X-band SAR payload and ground reception/processing subsystems are designed and the key design results are demonstrated with the outstanding performance characteristics. The designed small satellite SAR system shows the wide range of imaging capability, and proves to be an effective surveillance systems in the light weight, high performance and cost-effective points of view.