• Satellite Communications and Space Industry
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• v.12 no.1 s.27
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• pp.115-121
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• 2004

본 연구의 목적은 2008년 발사를 목표로 개발 중인 통신해양기상위성(COMS: Communication, Ocean and Meteorological Satellite) 1호의 해양/기상 임무를 수행을 지원할 지상 시스템의 개념 설계를 수행하는 것이다. 송수신 시스템 개발을 위한 사용자 요구사항 분석과 외국 정지궤도의 위성의 영상 전 처리 시스템에 대한 기법 분석이 이루어 졌으며, 이를 바탕으로 통신해양기상위성 송수신 시스템의 데이터 흐름도를 작성하였다. 통해기 지상 시스템은 신뢰성 있는 위성 운영과 자료처리 기술의 자립화를 위해 국내 기술로 자체 개발될 예정이다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.11
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• pp.76-83
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• 2006

Space radiation environment for COMS is simulated by NASA AP8/AE8, JPL91 and NRL CREME models, respectively for trapped particle, solar proton and cosmic-ray. The radiation effects on electronic devices in communication payload are also estimated by using simulation results. Dose-depth curve and LET spectrum are calculated for estimating total ionizing dose(TID) effect and single event effect(SEE) respectively. Spherical sector method is applied to dose estimation at each position in the units of communication payload to consider shielding effect of platform and housing. Total ionizing dose at each position varies by 8 times through shielding effect under the same external space radiation environment.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.2
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• pp.121-130
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• 2009

In this paper, the attitude and orbit control subsystem technology of new GEO communication and observation satellite using Sun sensors are introduced and analyzed. COMS is new GEO communication and Earth observation satellite based on EUROSTAR 3000 space bus technology. The attitude and orbit control subsystem of COMS adopts a configuration using three BASS and three LIASS Sun sensors to acquire the attitude error information in the specific reference frames. These Sun sensors are used to acquire Sun direction and to control the spacecraft to keep the relative attitude with respect to a reference Sun direction in both transfer and operational orbits. In this paper, the mathematical models of BASS and LIASS are described as well as their operational implementation in the flight software.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.103-108
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• 2007

Eurostar 3000 AOCS is optimized for telecommunication mission with no strong requirement on attitude stability and has therefore to be upgraded to comply with COMS high stability requirements for the optical observations. This COMS configuration constraint induces specificities for the wheel. The aim of this analysis is to verify the electrical compatibility of the interfaces which exist between COMS wheels and external equipments. For each interface, this study checked the compatibility between equipments for the power links, commands, digital telemetry, analog telemetry, and failure condition or AIT errors. In addition with this interface compatibility verification, this study outputs electrical and manufacturing recommendations to be applied at harness level.

• Aerospace Engineering and Technology
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• v.11 no.2
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• pp.12-18
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• 2012

In this paper, impacts on the COMS MI images during the COMS eclipse period were analyzed and the method to eliminate the contaminated area was investigated. Main effect on the meteorological images during the eclipse is a stripping effect due to a strong stray light. The quantitative analyses were conducted during the COMS In-Orbit-Test period and the impacts of the stray light on the four infrared channels of the COMS MI according to the distance with respect to the Sun were examined. Based on the typical case of the stray light influence on the infrared channel of the MI, the intensity of contamination due to the stray light was investigated for each channel using the computed COMS eclipse information. The effectiveness of removal of a contaminated area by replacing the SWIR with the combined WINDOW channels was promising.

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.99-107
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• 2008

The COMS is a kind of geostationary multi-functional satellites with three different mission objectives. Two of them aim at earth observation and the COMS has two optical payloads according to those missions. The payloads are composed of a meteo imager and an ocean color imager, and their inherent characteristics require optimal interface design for their performance to be concurrently achieved. Therefore, various kinds of constraints are considered in their component accommodation on the COMS platform. This paper shows a general overview of the optical payload accommodation design and describes the design consideration to achieve the optimized performance from thermal and mechanical point of view.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.30-34
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• 2012

National Meteorological Satellite Center(NMSC) of Korea Meteorological Administration(KMA) has launched to implement the application development to get prepared for the space weather operation since 2010. As a action of KMA's space weather work, NMSC constructed Global Navigation Satellite System(GNSS) application system for meteorology and space weather. We will introduce NMSC's space weather application system which derives regional TEC(Total Electron Content) in near real time using nation-wide GNSS network data. First, We constructed system for collecting GNSS data, which is currently collecting about 80 stations operated by agencies like NGII(National Geographic Information Institute), Central Office of DGPS(Differential GPS), and KASI(Korea Astronomy and Space Science) including KMA's own data of 2 stations. In order to retreive regional TEC over Korean peninsular, we build up the automatic processes running every 1-hour. In these processes, firstly, GNSS data of every stations with 24 hours time window are processed to derive DCBs(Differential Code Biases) of each GNSS station and TEC values on every ionosphere piercing point(IPP). Then we made gridded regional TEC map with resolution of 0.25 degree from 31N, 121E to 41N, 135E by combination of all station results within 30 minutes window with assumption that TEC of a given point during a given 30 minutes window would have a constant value. The grid points without TEC value are interpolated using Barnes objective analysis. We presentour regional TEC maps, which can describe better on the status of ionosphere over Korean peninsular compared to IGS TEC maps.

• Aerospace Engineering and Technology
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• v.4 no.1
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• pp.95-102
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• 2005

This paper introduces the LAE(Liquid Apogee Engine) and station acquisition fuel budget estimation method for the COMS(Communication, Ocean and Meteorological Satellite) of Korea which is planned to be launched in 2008. And the estimation results are also presented. A statistical approach, more specifically, the Monte-Carlo method was employed to have the estimation include the effect of the launch vehicle GTO injection accuracies. A case study was conducted for several potential launch vehicles to compare the fuel requirements.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.95-102
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• 2008

COMS Satellite is automatically able to recover from any defined failure thanks to a full redundancy. This study assesses the effects of gyro failure on the COMS mission and analyzes the mechanism of Gyro Failure Detection, Isolation and Recovery about failure detection means, isolation and recovery actions and their consequences. At last, it checks the FDIR behavior from an injected failure on COMS simulator.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.119-125
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• 2006

The first GEO satellite, COMS(Communication. Ocean & Meteorological Satellite) developed by Korean participants is a multi-functional satellite accommodating two observation payloads and a communication payload. Because of the inherent requirements given by these payloads, the physical layout of the instruments and sensors and of their electronics packages is critical to mission success. This technical paper presents an overview of the mechanical system design during the preliminary design phase and describes the design consideration to achieve the optimized performance.