• Journal of Space Technology and Applications
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• v.1 no.3
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• pp.337-355
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• 2021

This paper is made to suggest a future strategy for the Korean High Resolution Wide Swath Synthetic Aperture Radar (HRWS SAR) satellite development by surveying the current trends for the SAR satellite technologies. From the survey, the latest SAR technology trends are revealed of using Digital Beam-Forming (DBF), SCan-On-Receive (SCORE), Displaced Phase Center Antenna (DPCA), interferometry, and polarimetry for exploiting the SAR imagery. Based on the latest SAR technology trends and the foreign HRWS SAR development cases, the strategy for the future HRWS Korean SAR satellite development is suggested to develop the DPCA and SCORE technologies by using the KOrea Multi-Purpose SATellite-6 (KOMPSAT-6) which is going to launch in a few years, and consequently to develop the HRWS SAR satellites which can monitor the whole Earth at weekly intervals.

• Journal of Space Technology and Applications
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• v.1 no.2
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• pp.268-281
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• 2021

Recently, the synthetic aperture radar (SAR) has been increasingly in demand due to its advantage of being able to observe desired points regardless of time and weather. To utilize SAR data, first of all, many pre-processing such as satellite orbit correction, radiometric calibration, multi-looking, and geocoding are required. For analysis of SAR imagery such as object detection, change detection, and DEM(Digital Elevation Model), additional processings are needed. These pre-processing and additional processes are very complex and require a lot of time and computational resources. In order to handle the SAR images easily, the institutions that use SAR images develop analysis tools and provide users. This paper introduces the function and characteristics of representative SAR imagery analysis tools.

• 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.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.2
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• pp.25-32
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• 2009

In this paper, the technical trends of the synthetic aperture radar (SAR) were studied by investigating the journals and conference associated with the advanced technology of SAR. SAR has been first demonstrated in 1950. The main objective of SAR development is to overcome the limitations of real aperture radars. From 1950, many new concepts and technologies for SAR system is suggested and realized by many international researchers and engineers. New concepts for future SAR systems represented in the recent conference have been rearranged and analyzed.

• Aerospace Engineering and Technology
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• v.13 no.2
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• pp.131-141
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• 2014

Synthetic Aperture Radar (SAR) is a powerful and well established microwave remote sensing technique which enables high resolution measurements of the Earth surface independent of weather conditions and sunlight illumination. In this study, this paper first summarizes the basic SAR theory and the history of the SAR satellites. The second part of this paper gives an overview of new technologies for future SAR systems. New innovative concepts and technologies for SAR satellites will be digital beamforming, High Resolution Wide Swath (HRWS), Waveform Encoding, Terrain Observation by Progressive Scan (TOPS), and so on. These technologies will play an important role for future spaceborne SAR satellites.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.1
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• pp.88-106
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• 2011

최근 고해상도의 영상 레이다(Syntetic Aperture Radar. SAR) 기술의 급속한 발전으로 기상의 변화에 관계없이 전천후로 지구의 환경 변화를 관측하거냐 고정밀도의 표적 탐지 및 식별이 가능해짐에 따라 레이다 영상을 이용한 활용 분야가 군사 목적의 정밀 감시 정찰뿐만 아니라 과학 및 민수용으로도 활용범위가 넓어지고 있다. SAR의 역사는 1950년대부터 약 50년의 기술 역사를 가지고 있지만 2010년을 기점으로 최근 3~4년 사이에 전 세계적으로 유사 이래 가장 많은 10여개 이상의 저궤도 SAR 위성들을 발사하므로서 비로소 "저궤도 위성 SAR 전성시대"로 진입하게 되었다. 우리나라에서도 최근 다목적 실용위성 5호에 SAR를 탑재하는 최초의 영상 레이다 위성을 2011년 중반에 궤도에 집입시키기 위하여 현재 발사를 준비하고 있다. 본 논문에서는 2011년 9월 26~30일 한국에서 처음으로 개최되는 국제영상 레이다 학술대회(Asia-Pacific Conference on Synthetic Aperture Rader: APSAR 2011)에 즈음하여 위성 SAR 개발 동향을 중심으로 SAR 기술 특정과 활용 기술 및 최근 기술 발전 동향을 소개한다.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.6
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• pp.4-16
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• 2011

영상 레이다(Synthetic Aperture Radar: SAR)는 기상조건이나 주야에 관계없이 전천후로 광범위한 지역의 영상을 고해상도로 얻을 수 있는 능동형 전자파 레이다 센서이다. 최근 세계적으로 위성 SAR는 2010년을 기점으로 최근 3~4년 사이에 유사이래 가장 많은 13개 이상의 저궤도 소형 SAR 위성들을 발사함에 따라 비로소 "저궤도 위성 SAR 전성기"로 진입하게 되었다. 우리나라에서도 아리랑위성 5호(KOMPSAT-5)에 SAR를 탑재하는 최초의 레이다 위성을 올해 2011년에 발사할 계획을 가지고 있으나 아직 발사가 지연되고 있다. 본 기고에서는 2011년 9월 27~30일 서울에서 개최된 국제 영상 레이다 학술 대회 APSAR 2011(Asia-Pacific Conference on Synthetic Aperture Radar)의 성공을 기념하여 마련된 SAR 기술 특집호에 최신 위성 SAR 개발 동향을 중심으로 기술 발전 추세와 전망에 대하여 소개한다.

• Aerospace Engineering and Technology
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• v.8 no.1
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• pp.187-196
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• 2009

Synthetic Aperture Radar(SAR) satellite system for broad-area imaging has RF systems including SAR radiating a high power, data link system transmitting the acquired image data from the SAR, TC&R(Telemetry, Command, and Ranging) to communicate with a ground segment to control a satellite. Each system transmits RF signal having various frequencies and radiates a high power, RS(Radiated Susceptibility) specification should be verified at an electronic unit mounted in satellite. RF interference can be happened because of non-linearity of a RF system. Therefore, we manufactured a structure model installed antennas which have a similar pattern with a real antenna, the effect by RF interference is analyzed and verified.

• Journal of Satellite, Information and Communications
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• v.12 no.3
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• pp.63-68
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• 2017

SAR(Synthetic Aperture Radar) uses electromagnetic signals to acquire ground information and has been used for wide coverage reconnaissance missions regardless of weather conditions. However SAR is known to be vulnerable to interference signals by other communication devices or radar instruments and may suffer from undesirable performance degradations and image quality. In this paper, a modified Eigen-subspace based filter is proposed that can be easily applied to SAR images affected by interference signals. The method of constructing Eigen-subspace based filter is briefly described and various simulations are performed to show the performance of the interference mitigation process. The suppression filter is applied to a ALOS PALSAR raw data affected by interfering signals in order to verify its superiority over the Notch filter.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.663-668
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• 2008

Recently, World Radio Conference(WRC)-2007 approved the ultrawide bandwidth of 500 MHz for the use of spaceborne synthetic aperture radar in X-band for the EESS(Earth Exploration Satellite Service) in order to improve the SAR imaging resolution. It is concerned about the interference impact from the spaceborne SAR that may cause to most of ground radars due to the extended ultra wideband. In this paper, in order to predict the interference impact of the ground-based radar from the spaceborne radar, radar interference model is presented using radar characteristic parameters by taking into account the operating environments of the spaceborne and ground based radar in the time, space, and spectrum domains. Using the spaceborne SAR model of TerraSAR-X and ground radar model of meteorological radar recommended by ITU-R, the interference impact was assessed through the computer simulation to see the possible interference impact of the ground based radar operating in the Korean peninsula.