• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.183-186
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• 2007

The aim of this analysis is to verify the electrical compatibility of the interfaces which exist between COMS(Communication, Ocean and Meteorological Satellite) AOCS(Attitude Orbit Control Subsystem) equipments 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. In addition with this interface compatibility verification, this study outputs the electrical and manufacturing constraints to be applied at harness level.

• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.87-95
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• 2007

The ocean and meteorological payloads of COMS are concerned to experience degration of image quality due to the disturbance induced by the motion of moving parts of the payloads. And thruster firings for stationkeeping and wheel offloading are expected to degrade the image quality of the optical payloads. In case of COMS, in order to keep the optical payload free from the mechanical interference from the other payload, the operation design approach has been taken. This paper introduces the operation design of COMS taken to avoid these problems. In order to meet users requirement by avoiding the degradation of image quality, the timeline of optical payloads and housekeeping are optimized, and operational constraints are applied to the mirror motion of the meteorological payload. This paper also introduces the results of time budget analysis performed to validate the operation design.

• 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.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.268-271
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• 2005

COMS (Communication, Ocean, and Meteorological Satellite) will be launch at end of year 2008. For receiving of COMS LRlT, KARl (Korea Aerospace Research Institute) finished design and software realization of COMS SDUS (Small Data Utilization System). SDUS is a small station receiving LRlT data for distribute satellite image, weather information, and so on. For the future project, KARl preparing COMS MDUS (Mass Data Utilization System) that can receiving large size of data over than 2M BPS (Bit Per Seconds) data size.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.498-500
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• 2004

QPSK (Quaternary Phase Shift Keying) will be adopted as the modulation of HRIT (High Rate Information Transmission) which is transmitted to COMS (Communication, Ocean and Meteorological Satellite) through HPA (High Power Amplifier) in ground segment. Due to the nonlinearity of HPA, IMD (Inter-Modulation Distortion) of multi-carrier signals and PAPR (Peak-to-Average Power Ratio) of modulated HRIT must be considered to estimate the output power of HPA. In this paper, we measured the PAPR to various the roll-off factor of RRC (Root Raised Cosine filter) which is filtering the modulated HRIT signal for reducing ISI (Inter-Symbol Interference) and bandwidth. It was found that the minimum PAPR is 2.78dB at 0.5 of roll-off factor for scrambled data. It's 2.78dB of P APR will be in output power selecting in COMS earth station.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.607-615
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• 2017

The aerosol optical thickness data retrieved by Moderate Resolution Imaging Spectrometer (MODIS) of Terra & Aqua and Meteorological Imager (MI) of Communication Ocean and Meteorological Satellite (COMS) are analyzed and compared with the measurement data of Aerosol Robotic Network (AERONET) in Northeast Asia. As the result, the aerosol optical thickness retrieved by MODIS and MI were well agreed at ocean region but quite different at cloud edge and barren surface. The reason was that MODIS aerosol optical thickness was retrieved using the visible and infrared channels but MI was retrieved with the visible channel only. Consequentially, the thin cloud be misinterpreted as aerosol by MI and the difference between MODIS and MI aerosol optical thicknesses could be occurred with Normal Distribution Vegetation Index (NDVI) and land surface property. Therefore, the accuracies of clear/cloud region and surface reflectivity are required in order to improve the aerosol optical thickness algorithm by MI.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.227-231
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• 2007

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and has been developing by KARI for communication and ocean and meteorological observations. It will be launched by ARIANE 5. Ka-band components are installed on South panel, where single solar array wing is mounted. Radiators, embedded heat pipes, external heat pipe, insulation blankets and heaters are utilized for the thermal control of the satellite. The Ka-band payload section is divided several areas based on unit operating temperature in order to optimize radiator area and maximize heat rejection capability. Other equipment for sensors and bus are installed on North panel. The ocean and meteorological sensors are installed on optical benches on the top floor to decouple thermally from the satellite. During the transfer orbit operation, satellite will be under severe thermal environments due to low dissipation of components, satellite attitudes and LAE(Liquid Apogee Engine) firing. This paper presents temperature and heater power prediction and validation of thermal control design during transfer orbit operation.

• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.75-81
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• 2010

COMS (Communication, Ocean and Meteorological Satellite) is the multi-purposed Korean geostationary satellite funded by four Korean government ministries, and is to supply communication services, ocean and weather observation for 7 years. As part of COMS, development of Ka band communication payload composed of microwave switching transponder and multi-horn antenna is sponsored by KCC (Korea Communications Commission) and developed by ETRI (Electronics and Telecommunications Research Institute). The purpose of Ka Payload development is to acquire space proven technology of Ka payload and to exploit advanced multimedia communication services. This paper aims to study development technology of Ka payload system through whole process of ETRI project. Also application of Ka payload will be dealt in this paper.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.53-56
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• 2007

The Korean Geostationary satellite (COMS) to fly in year 2009 will carry a meteorological sensor from which visible channel measurements will be available. We developed a method utilizing satellite-derived BRDFs for the solar channel calibration over the bright desert area. The 6S model has been incorporated to account for directional effects of the surface using MODIS-derived BRDF parameters within the spectral interval in interest. Simulated radiances over the desert targets were compared with MODIS and SeaWiFS measured spectral radiances in order to examine the feasibility of the developed calibration algorithm. We also simulated TOA radiance over ocean targets to verify the consistency and reliability of the result. It was shown that simulated 16-day averaged radiances are in good agreement with the satellite-measured radiances within about ${\pm}5%$ uncertainty range for the year 2005, suggesting that the developed algorithm can be used for calibrating the COMS visible channel within about 5% uncertainty level.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.110-115
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• 2012

Satellite structure should be designed to accommodate and support safely the payload and equipments necessary for its own missions and to secure satellite and payloads from severe launch environments. The launch environments imposed on satellites are quasi-static accelerations, aerodynamic loads, acoustic loads and shock loads. Currently KARI(Korea Aerospace Research Institute) is developing Geo-KOMPSAT-2(Geostationary Earth Orbit KOrea Multi-Purpose Satellite) with technologies which were acquired during COMS(Communication, Ocean and Meteorological Satellite) development. As compared to COMS Geo-KOMPSAT-2 requires more propellant due to mass increase of Advanced Meteorological Payload with high resolution and increase of miss life, it is difficult to apply the design concept of COMS to Geo-KOMPSAT-2. This paper deals with conceptual design of Structural Subsystem for Geo-KOMPSAT-2.