• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.497-499
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• 2006

There are several types of communication method which is used for the supply of electric power stably. But the communication methods used in KEPCO have weak points in the viewpoint of economy, technology and management. The Satellite communication systems have competitive power in price and technology for national wide utility owing to its wide area coverage and stability. This paper presents various adapted examples of the Power industry using he satellite communication systems.

• ETRI Journal
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• 제23권4호
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• pp.199-201
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• 2001

The phase noise reduction in a configuration of the HEMT oscillator with a dielectric resonator coupled by a quarter-wavelength impedance inverter is investigated. Two HEMT oscillators for a satellite payload system are manufactured in the same configuration except for the coupling configuration of the dielectric resonator (DR) in order to empirically demonstrate the phase noise reduction. Experimental result shows that a phase noise reduction by 14 dB can be enhanced by increasing the characteristic impedance of a coupling microstrip impedance inverter.

• 한국통신학회논문지
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• 제32권5A호
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• pp.441-450
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• 2007

본 논문에서는 위성망 자원할당 및 분석 툴(SNRAT : Satellite Network Resource Allocation & Analysis Tool)을 활용하여 위성통신체계에 대한 링크성능 분석결과를 제시하였으며, 모의위성망을 구성하여 성능분석 툴로 예측한 링크 성능을 검증하였다. 통신위성은 지상장비와 달리 정지궤도에 발사하여 궤도 내 운용을 시작하면, 더 이상 성능의 수정이나 수리가 불가능하고, 운용 가능한 수명이 제한되어 있기 때문에 적기에 배치하여 운용하는 것이 매우 중요하다. 따라서, 위성 발사 전 위성망 자원할당 및 분석 툴을 이용하여 통신품질, 지원용량 및 항재밍 성능 등을 예측하고, 모의위성망을 구축하여 지상단말과 망제어기와 같은 지상장비 및 중계기 규격의 적합성을 증명하였으며, 여러 망 운용 시나리오에 대한 시험을 통해 최적의 운용방안을 도출하였다.

• International Journal of Aeronautical and Space Sciences
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• 제1권2호
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• pp.50-67
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• 2000

The spacecraft simulator is used for command validation, operational check of the Satellite Operation Subsystem (SOS), spacecraft anomaly analysis support, satellite operator training etc. In this paper, S/W design features and modeling characteristics of the KOMPSAT Spacecraft Simulator Subsystem (SIM) are described. Validation procedures and simulation results are also provided. The SIM provides extensive simulation capabilities by including models for most of the spacecraft subsystems. The software structure of the SIM was designed and implemented so as to support operations not only in real-time but also in non real-time by utilizing the Hewlett Packard (HP) UNIX functions. The SIM incorporates as many user-friendly Man Machine Interface (MMI) windows as possible so that all the SIM normal operations can be executed through the MMI windows.

• 정보보호학회논문지
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• 제11권4호
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• pp.15-31
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• 2001

본 논문에서는 위성통신망의 보안 위협요소를 위성통신망의 특성과 데이터를 바탕으로 Level-0(위성 전파 신호), Level-1(위성 관제 데이터). Level-2(위성 응용 데이터) 그리고 지상망 보안 단계로 분류한다. 그리고 각 보안 단계에 대한 위협 요소를 분석한다. 그 후 도출된 위성통신망 보안 위협요소에 대한 보안 요구 사항을 신호보안과 정보보안 레벨로 나누고, 이를 근거로 기존의 신호보안 수준의 대응방안에서 벗어나 위성통신 네트워크 보안, 위성통신망 시스템 보안, 위성통신망 데이터 보안등의 정보보안 레벨에서 정보보호 정책을 통한 위성통신망 보안 위협요소 대응방안을 수립한다. 이와 같은 정보보호 정책 기반의 대응방안을 통해 본 논문에서는 안전한 위성통신망 보안 구조를 제안한다.

• 산업경영시스템학회지
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• 제41권1호
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• pp.39-49
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• 2018

In the satellite operation phase, a ground station should continuously monitor the status of the satellite and sends out a tasking order, and a satellite should transmit data acquired in the space to the Earth. Therefore, the communication between the satellites and the ground stations is essential. However, a satellite and a ground station located in a specific region on Earth can be connected for a limited time because the satellite is continuously orbiting the Earth, and the communication between satellites and ground stations is only possible on a one-to-one basis. That is, one satellite can not communicate with plural ground stations, and one ground station can communicate with plural satellites concurrently. For such reasons, the efficiency of the communication schedule directly affects the utilization of the satellites. Thus, in this research, considering aforementioned unique situations of spacial communication, the mixed integer programming (MIP) model for the optimal communication planning between multiple satellites and multiple ground stations (MS-MG) is proposed. Furthermore, some numerical experiments are performed to verify and validate the mathematical model. The practical example for them is constructed based on the information of existing satellites and ground stations. The communicable time slots between them were obtained by STK (System Tool Kit), which is a well known professional software for space flight simulation. In the MIP model for the MS-MG problems, the objective function is also considered the minimization of communication cost, and ILOG CPLEX software searches the optimal schedule. Furthermore, it is confirmed that this study can be applied to the location selection of the ground stations.

• 한국위성정보통신학회논문지
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• 제8권2호
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• pp.80-87
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• 2013

통신, 해양, 기상의 세 분야 복합 임무를 수행하는 천리안위성(Communication Ocean Meteorological Satellite: COMS)은 정지궤도 동경 $128.2{\circ}$에서 2011년 4월부터 현재 정상 운영 임무를 수행하고 있다. 세 임무를 수행하기 위해 천리안위성에는 3가지 탑재체인 기상탑재체(Meteorological Imager: MI), 해양탑재체(Geostationary Ocean Color Imager: GOCI), 통신탑재체(Ka-band communication payload)가 실려 있다. 세 가지 임무 운영과 위성 유지 관리를 위해 위성 관제가 실시간 운영으로 수행된다. 위성 실시간 운영은 명령과 원격측정자료를 통해 위성과 직접 통신하는 업무이다. 본 논문에서는 천리안위성의 실시간 운영 특성으로 지상국 장비 구성과 일일, 주간, 월간, 계절별, 연간 운영 업무 특성을 논하였다. 천리안위성의 궤도상 시험(In-Orbit-Test: IOT) 말기와 정상 운영 첫 해가 포함되는 2011년의 1년간 운영 결과에 대한 토의를 통해 성공적인 실시간 운영 결과 확인도 제시하였다.

• 전자공학회논문지D
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• 제34D권6호
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• pp.75-82
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• 1997

Today's wireless communication needs the super-high speed for picture transmission as well as voice. The optical communication with the very wide bandwidth is suitable for this demand. To fulfill the optical wireless communication, however, the atmospheric attenuation in rainy weather condition must be overcome. In the optical satellite up-link communication between geo-satellite and earth station, the factors of attenuation are turbulence, pointing error, scattering, and so on. The most serious factor for these is the scattering by rain. Under the weather conditiion of rain and cloud, in this paper, the atmospheic attenuation which affects the optical satellite up-link communication was considered, and the optimum idameter of the optical satellite transmitting antenna in the earth station versus elevation angles, data rates and rainfall rates was presented.

• 우주기술과 응용
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• 제3권2호
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• pp.144-153
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• 2023

기존의 군 위성 통신체계는 적의 재밍 공격 및 신호 수신을 대비한 특수한 통신 탑재체가 장착된 정지궤도 통신위성을 기반으로 하였는데, 무인체계 등 새로운 무기체계가 등장함에 따라 신규 통신 수요를 충족시킬 저궤도 위성 기반의 위성 통신체계의 필요성이 점점 커지고 있다. 본 논문은 큐브 위성 기반의 통신체계에 적합한 다양한 웨이브폼 기술과 미래 군 초소형 위성 통신체계의 운용 개념에 대해 소개한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.56-59
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• 2006

In this paper, Korea's first geostationary Communication, Ocean and Meteorological Satellte(COMS) program is introduced. COMS program is one of the Korea National Space Programs to develop and operate a pure civilian satellite of practical-use for the compound missions of meteorological observation and ocean monitoring, and space test of experimentally developed communication payload on the geostationary orbit. The target launch of COMS is scheduled at the end of 2008. COMS program is international cooperation program between KARI and ASTRIUM SAS and funded by Korean Government. COMS satellite is a hybrid satellite in the geostationary orbit, which accommodates multiple payloads of MI(Meteorological Imager), GOCI(Geostationary Ocean Color Imager), and the Ka band Satellite Communication Payload into a single spacecraft platform. The MI mission is to continuously extract meteorological products with high resolution and multi-spectral imager, to detect special weather such as storm, flood, yellow sand, and to extract data on long-term change of sea surface temperature and cloud. The GOCI mission aims at monitoring of marine environments around Korean peninsula, production of fishery information (Chlorophyll, etc.), and monitoring of long-term/short-term change of marine ecosystem. The goals of the Ka band satellite communication mission are to in-orbit verify the performances of advanced communication technologies and to experiment wide-band multi-media communication service mandatory.