• Journal of Astronomy and Space Sciences
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• 제17권1호
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• pp.117-122
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• 2000

The KOMPSAT(Korea Multi-Purpose SATellite) has two optical imaging instruments called EOC(Electro-Optical Camera) and OSMI (Ocean Scanning Multispectral Imager). The image data of these instruments are transmitted to ground station and restored correctly after post-processing with the telemetry data transfeered from KOMPSAT spacecraft. The major timing information of the KOMPSAT is OBT (On-Board Time) which is formatted by the on-board computer of the spacecraft, based on 1Hz sync. pulse coming from the GPS receiver involved. The OBT is transmitted to ground station with the house-keeping telemetry data of the spacecraft while it is distributed to the instruments via 1553B data bus for synchronization during imaging and formatting. The timing information contained in the spacecraft telemetry data would have direct relation to the image data of the instruments, which should be well explained to get a more accurate image. This paper addresses the timing analysis of the KOMPSAT spacecraft and instruments, including the gyro data timing analysis for the correct restoration of the EOC and OSMI image data at ground station.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.159-162
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• 2006

This paper describes the ground system for COMS (Communication, Ocean, and Meteorological Satellite), the first Korean multi-purposed geostationary satellite, at MSC (Meteorological Satellite Center) in Korea. The overview of COMS MI (Meteorological Imager) will be introduced as well. KMA would implement mission planning for COMS MI operation and receive, process, interpret, disseminate, and archive MI data operationally for domestic and foreign user groups. Major missions of COMS MI are mitigation of natural hazard such as typhoon, dust storm, and heavy rain, and short-term warning of severe weather to protect human health and commerce. Moreover, research of climate variability and long-term changes will be supported. In accordance with those missions, the concept and design of COMPASS (COMS operation and meteorological products application service system), the ground system for COMS MI in MSC, have been setting up since 2004. Currently, COMPASS design is being progressed and will have finished the end of 2006. The development of COMPASS has three phases: first phase is development of fundamental COMPASS components in 2007, second phase is to integrate and test all of the COMPASS components in 2008, and the last phase is to operate COMPASS after COMS In-Orbit Tests in 2009.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.222-227
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• 2002

This research will examine into the capabilities of KOMPSAI-1 EOC image application in the field of urban environment and at the same time, with that as its foundation, come to understand the urban changes of the study areas. This research is constructed in three stages: Firstly, for application of change detection techniques, which utilizes multi-temporal remotely sensed data, the data normalization process is carried out. Secondly, change detection method is applied fur the systematic monitoring of land use changes, which utilizes multi-temporal EOC images. Lastly, by using the results of the application of land use changes, the existing land use map is updated. Consequently, the land-use change patterns are monitored, which utilize multi-temporal panchromatic EOC image data; and application potentials of ancillary data fur updating existing data can be presented. In this research, with the use of the land use change, monitoring of urban growth has been carried out, and the potential for the application of KOMPSAT-1 EOC images and the scope of application was examined. Henceforth, the future expansion of the scope of application of KOMPSAT-1 EOC image is anticipated.

• 대한원격탐사학회지
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• 제30권3호
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• pp.375-381
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• 2014

Soil moisture is an essential satellite-driven variable for understanding hydrologic, pedologic and geomorphic processes. The European Space Agency (ESA) has endorsed soil moisture as one of Climate Change Initiates (CCI) and had merged multi-satellites over 30 years. The $0.25^{\circ}$ coarse resolution soil moisture satellite data showed correlations with variables of a water stress index, Temperature-Vegetation Dryness Index (TVDI), from a stepwise regression analysis. The ancillary data from TVDI, Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) from MODIS were inputted to a multi-regression analysis for estimating the surface soil moisture. The estimated soil moisture was validated with in-situ soil moisture data from April, 2012 to March, 2013 at Andong observation sites in South Korea. The soil moisture estimated using satellite-based LST and NDVI showed a good agreement with the observed ground data that this approach is plausible to define spatial distribution of surface soil moisture.

• 한국항공운항학회지
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• 제16권2호
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• pp.12-20
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• 2008

Japanese MSAS (Multi-functional Satellite Augmentation System) satellites have been transmitting GPS satellite orbit and ionosphere correction information since 2005. MSAS coverage includes Far East Asia, and it can improve the accuracy and integrity of GPS position solutions in Korea. This research analyzed the ionosphere correction information from the MSAS ionosphere correction data. The ionosphere delay data observed by a dual frequency receiver is compared with the MSAS ionosphere correction data. The variation of MSAS GIVE values are analyzed in connection with the equatorial anomaly and ionosphere scintillation.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1052-1054
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• 2003

RAZAKSAT is a second micro-satellite mission by Malaysian Satellite Program and is expected for launch in June 2004. Designed to orbit the earth at low-equatorial orbit, RAZAKSAT will meet Malaysia’s immediate needs to rapid data acquisition (real time and more repetitions) to address many operational issues of remote sensing applications, which require availability of current data sets. RAZAKSAT will be among the first remote sensing satellite to orbit the earth at low inclination along the equator, 9$^{\circ}$ with 685km altitude, hence, allows optimal geographical information and environment change within equatorial region be observed with a unique revisit characteristics. The satellite primary payload is MAC, a push-broom type camera with 2.5m of ground sampling distance (GSD) in panchromatic band and 5m of GSD in four multi-spectral bands. This paper describes on the variation of illumination anticipated from simulated RAZAKSAT image, examine its implication to its ground leaving radiances for major applications.

• 대한원격탐사학회지
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• 제5권1호
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• pp.29-39
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• 1989

A study to develop generalized and systematically designed satellite image processing software system on mainframe computer was successfully carried out. Commercially available softwares such as LARSYS were analyzed and modified, and well known satellite data processing algorithms were implemented into comprehensive software. New algorithms were also presented and developed. The contents of developed softwere system may be divided into 8 major sections: menu and user interface, data file management, preprocessing, enhancement in monochrome image, multi-dimension image analysis, scene classification, image display/hardcopy, image handle utility software. Some additional software such as GIS and DBMS will make this software more comprehensive and generalized one for the satellite data processing.

• 한국항공우주학회지
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• 제35권9호
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• pp.836-842
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• 2007

본 논문에서는 자동으로 궤도를 결정하고, 신뢰성을 판정한 후 임무계획, 위성추적, 위성위치 표시에 사용하도록 갱신하며, 안테나 추적을 위해 필요한 여러 가지 형태의 궤도데이터 파일을 생성하는 ‘자동 궤도운용 시스템 (KGS automated Operational Orbit Processing System, KOOPS)'의 개발 내용 및 실제 운용 결과를 기술하였다. 개발된 본 시스템은 다양한 형태의 궤도추적 데이터를 처리할 수 있으며, 각 위성 시스템에 따라 필요한 다양한 전처리 및 후처리 프로세스들을 각 위성 별로 개별적으로 설정할 수 있기 때문에 여러 기의 서로 다른 임무를 가진 “다중, 복합” 위성 궤도운용 시스템으로 적용이 가능하다. 아리랑 1호 및 아리랑 2호의 추적 및 임무계획을 위한 비행역학 시스템으로써 적용되어 운용한 결과, 임무운용의 효율성 및 안정성을 크게 높이고, 인력 소요를 대폭 줄이는 효과를 얻을 수 있었다. 본 시스템의 개발 과정과 실제 적용을 통해 얻은 경험은 향후 보다 효율적이고 자동화된 “통합지향형 범용” 비행역학 시스템 개발에 직접 활용될 수 있을 것으로 사료된다.

• 한국전자파학회논문지
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• 제24권10호
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• pp.1001-1007
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• 2013

다수의 저궤도 위성을 운영하는 경우, 위성별 운영 궤도에 의해서 지리적으로 고정된 하나의 지상국은 2개 이상의 위성과 통신을 해야 하는 상황이 발생된다. 일반적으로 위성에서 관측된 영상 데이터를 수신 및 처리하는 시스템은 위성별로 다를 뿐만 아니라, 1:1 백업 구성을 함으로써 지상 수신 안테나가 한정되어 설치된 지상국에서는 위성의 수가 많아질수록 데이터 전달을 위한 안테나에서 영상 수신 처리 시스템 간의 접속 설계가 복잡해지는 문제가 발생된다. 본 논문에서는 2개의 위성에 대해 동시 운영이 가능하며, 위성별 영상데이터 저장장치를 연결함으로써 확장이 가능한 매트릭스 구조의 수신 채널 구현 내용이 작성되어 있다. 구현된 수신 채널은 다목적실용위성 3호 발사 이후에 운영 검증을 완료하였으며, 확장 기능을 통해 추후 발사될 5호와 3A호에 대해서도 적용할 예정이다.

• 한국정보통신학회논문지
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• 제16권1호
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• pp.20-25
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• 2012

천리안 위성은 해양 관측과 기상영상 전송, 그리고 Ka 대역 위성통신 신호 중계를 위한 다목적 복합위성으로 2010년 발사되어 운용되고 있다. Ka 대역 위성통신 중계기는 MSM 스위치 기능으로 다중 빔 지향이 가능하고 다중모드 고속 데이터를 전송할 수 있다. 천리안 위성통신 중계기는 MSM 기능으로 다수의 신호발생기와 Ka 대역의 주파수 사용으로 시스템 위상잡음이 증가할 수 있다. 위상잡음은 다중모드 및 고속 데이터 전송에 영향을 미치고 있으며, 높은 위상잡음을 갖는 위성 전송시스템은 전송 신호를 복원하기가 어렵다. 본 논문에서는 천리안 위성통신중계기의 위상잡음을 측정하고, 측정된 위상잡음을 수신 잡음대역폭 관점에서 위상잡음 영향을 분석하고 평가한다. 아울러, 천리안 위성통신 중계기 위상잡음에 대한 다중모드 및 고속 전송 데이터의 전송 성능을 평가한다.