• Atmosphere
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• v.12 no.4
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• pp.56-68
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• 2002

In this study, an overview of the Earth Observing System (EOS) program is provided with discussions on its spacecrafts and instruments, and on the scientific issues. The EOS satellites aim at monitoring the Earth environmental system by observing parameters of subsystems such as atmosphere, ocean, land, and biosphere. The first EOS flagship, Terra, was launched on December 1999. Five instruments onboard Terra can measure cloud and aerosol properties, radiation, terrestrial surface, and ocean color. The second EOS flagship, Aqua, which was launched on May 2002, loads six instruments that measure clouds, radiation, precipitation, terrestrial surface, ocean color and sea surface temperature. The observational data available from the EOS satellites may complement data from the Communication-Oceanography-Meteorology satellite, which will be launched in 2008, for meteorological and environmental forecasts.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.1
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• pp.82-89
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• 2008

In this paper a survey was conducted to find out the current components of bipropellant propulsion system for geosynchronous satellites. The purpose of the survey is to list up the alternative components corresponding to the components of chemical propulsion system (CPS) of the communication, ocean, and meteorological satellite (COMS), so that the criterion of survey is whether the alternative components can be applicable to COMS CPS or not. The survey results are described in component-by-component way and the short descriptions of each component and its companies are added. This paper can be useful for beginning a market survey and have a good understanding of the components of bipropellant propulsion system.

• Aerospace Engineering and Technology
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• v.8 no.2
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• pp.68-74
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• 2009

Infra-red earth sensors(IRES) are accommodated in a geostationary multi-functional satellite, which includes optical payloads for observing the earth, to provide pointing reference for the payloads. Even the slight pointing difference between the IRES and the payloads is so critical from the geostationary orbit that can degrade their imaging performance. Therefore, a dedicated support structure is required to guarantee the stability during the flight operation. This paper shows the design justification for the IRES support structure employed in the Communication, Ocean and Meteorological Satellite(COMS). It intends to give an overall design presentation and to justify that this design is compatible with all the requirements in terms of stiffness and strength as well as the stability.

• Aerospace Engineering and Technology
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• v.4 no.2
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• pp.88-93
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• 2005

A conceptual study about the angle information based orbit determination technique for a geostationary satellite was performed. With an assumption that the simultaneous observing of the earth and nearby stars is possible, we confirmed that the view angles between the earth and stars can be use as inputs for orbit determination process. By the MATLAB simulation with least square method, the convergence is confirmed. This conceptual study was performed with the COMS for instance. This technique will be able to use as a back-up of ground station's orbit determination or a part of autonomous satellite operation.

• Journal of computational fluids engineering
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• v.10 no.3 s.30
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• pp.63-69
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• 2005

The COMS, the first meteorological geostationary satellite in Korea, is under development by KARI. The radiator size and the heater power for the thermal control of COMS are calculated using an analytic method. The total radiator area of $4.85\;m^2$ and the total heater power of 794.77 W are determined at a conceptual design of COMS. The commercial software, SINDA and TRASYS, are utilized in order to compare and verify the analytic results. The results of on-orbit numerical simulation of cold and hot cases show that the radiator size and heater power obtained from the analytic method are appropriate to maintain COMS equipments within required temperature ranges.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.246-248
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• 2009

In this paper, we will describe architecture and key characteristic for the DHS which is used in COMS. DHS is implemented in the fully redundant SCU, the dual redundant MIL-STD-1553B system bus, the payload interface units(MPIU and MI2U), the redundant ADE. the SCU interface with the other main digital units of the spacecraft through the MIL-STD-1553B.

• Aerospace Engineering and Technology
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• v.8 no.2
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• pp.33-40
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• 2009

In this paper, the preliminary EMC analysis process between the Communication, Ocean and Meteorological Satellite (COMS) and Geostationary Earth Orbit (GEO) launch vehicles in the frequency range [1MHz-47MHz] is described. The launch vehicle Radiated Emission (RE) specifications have been compared to COMS satellite Radiated Susceptibility (RS) limits. The COMS RS limits are the RS qualification levels of COMS units during launch. The negative margins appear between land launch or soyuz launch vehicle RE and COMS RS. Then, if the land launch or soyuz is chosen by the customer, The tests should be performed at satellite level in order to demonstrate the compatibility with respect to launch vehicles specifications.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.459-470
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• 2008

DATS which is one of three subsystems of IDACS is responsible to receive Sensor Data, LRIT and HRIT in L-Band and transmit LRIT and HRIT in S-Band from/to COMS satellite. This paper shows detailed test procedures used to verify the performance and functionality of DATS after its implementation was completely finished. As a part of efforts to verify key DATS performance, G/T and EIRP were measured by using solar flux density as radio source. Regarding the verification of DATS functionality, RF loop-back test was conducted to validate if there is no BER degradation excepting MODEM/BB implementation loss occurred in the integrated DATS. Integrated with 13m antenna, DATS successfully restored image from received MTSAT-1R broadcasting data, LRIT and HRIT, of which frequencies are all L-Band. S-Band transmission was also verified through test antenna placed away from 13m antenna by measuring real LRIT and HRIT spectrum in S-Band. From those test results, DATS is determined to be fully ready to communicate with COMS in L-Band and S-Band.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.3
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• pp.3-16
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• 2011

천리안 위성은 4개 정부 부처 공동 사업으로, 통신 서비스, 해양 기상 관측 서비스 제공을 목적으로 개발된 복합 위성으로, 그중 통신 서비스를 담당하는 통신 탑재체는 방송통신위원회 출연으로 한국전자통신연구원(ETRI)가 주관, 개발하여 성공한 순수 국산 개발품으로, 위성 발사 성공 후 시험 검증을 거쳐 현재 정상 운용 중에 있다. 우주 인증 획득을 목적으로 개발한 통신 탑재체는 위성 스위칭 중계기와 다중 빔 안테나로 구성되었으며, 구성 부품들인 능동 부품과 수동 부품들은 대부분 국내 연구진에 의해 설계, 제작 시험 검증되어 중계기 및 안테나 시스템 종합화, 통신 탑재체 및 위성체 우주 환경 시험을 성공적으로 수행되었다. 위성 발사 성공 후에, 정지 궤도상에서의 통신 탑재체 궤도내 시험을 완료를 통해 순수국산 개발된 통신 탑재체의 설계 제작 기술에 대한 정지 궤도 우주환경에서도 정상 동작됨을 입증하였다. 통신 탑재체는 다양한 우주 조건에서의 다양한 기술 확보와 차세대 멀티미디어 위성 서비스 개발에 활용하고자 한다. 본 논문은 통해기 통신 탑재체 설계 제작 시험 기술을 소개하고, 활용 계획에 대해 언급하고자 한다.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.369-372
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• 2006