• Bulletin of the Korean Space Science Society
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• 2006.10a
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• pp.118-118
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• 2006

• Bulletin of the Korean Space Science Society
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• 2006.04a
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• pp.105-106
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• 2006

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.152-152
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• 2004

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.229-231
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• 1994

For the effective use of satellite communication transponder, tests for the payload system such as IOT(In-Orbit Test), RPM(Routine Payload Monitoring), CSM(Communicatios System Monitoring), and REV(Remote Earth-Station Verification) have to be conducted. Those tests are used in order to verify the condition and generic design of the satellite, to provide a database for operational calculations, and to maintain the quality of communication services. As the satellite communication system gets with wider expansion with higher complexity of operation, tests for the communication system also need more complex operation that usesophisticated computer-controlled measuring system. For and C language based measurement functions, which uses GPIB protocol and SCPI commands. But SICL requires knowledge of BASIC and C language as well as GPIB and SCPL system. This paper introduces a new language called CALSTEP-Control and Access Language for the Systems of Test Equipment and Payload. This language is designed for the operator to perform the tests for the satellite communication system without any special knowledge that is mentioned above. This language has very limited number of commands which are to be used to control the payload system and test equipments to perform IOT and CSM, and those commands are very readable and easy to understand, so an operator without any knowledge of BASIC and C programming language, or SICL and SCPI command can use it.

• Journal of Astronomy and Space Sciences
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• v.17 no.2
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• pp.257-266
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• 2000

A satellite RF communication link is analyzed based on a simple fundamental equations by systematic approach in this paper. The number of variables related to a design and analysis of satellite RF link is often a dozen or more, thus it is a tedious and time-consuming task. With the given input data, the important parameters are calculated step by step and three communication characteristics such as communication channel capacity, carrier-to-noise ratio(CNR) at the satellite and ground station are analyzed. It gives very useful information to the system engineers for designing and analyzing the overall satellite communication system in the conceptual design phase.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.149-149
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• 2004

• Journal of Astronomy and Space Sciences
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• v.37 no.1
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• pp.11-18
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• 2020

Satellite optical communication has gained significant attention owing to its many quality features (e.g., a larger bandwidth, license free spectrum, higher data rate, and better security) compared to satellite microwave communication. Various experiments have been performed during many space missions to demonstrate and characterize inter-satellite links, downlinks, and uplinks. Korea has also planned to establish an experimental communication system using a geostationary earth orbit (GEO) satellite and the Geochang station as an optical ground station for low Earth orbit (LEO)-to-ground optical relay links. In this study, the performance of inter-satellite communication links and downlinks was investigated for the new Korean experimental communication system in terms of link margin, bit error rate (BER), and channel capacity. In particular, the performance of the inter-satellite links was analyzed based on the receiving apertures and the transmitting power, while that of the downlink was analyzed in terms of atmospheric turbulence conditions and transmitting power. Finally, we discussed two system parameters of receiving aperture and transmitting power to meet the three criteria of link margin, BER, and channel capacity.

• Journal of Communications and Networks
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• v.12 no.6
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• pp.592-599
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• 2010

In recent years, significant improvements have been made to the techniques used for analyzing satellite communication and attacking satellite systems. In 2003, a research team at Los Alamos National Laboratory, USA, demonstrated the ease with which civilian global positioning system (GPS) spoofing attacks can be implemented. They fed fake signals to the GPS receiver so that it operates as though it were located at a position different from its actual location. Moreover, Galileo in-orbit validation element A and Compass-M1 civilian codes in all available frequency bands were decoded in 2007 and 2009. These events indicate that cryptography should be used in addition to the coding technique for secure and authenticated satellite communication. In this study, we address this issue by using an authenticated key-exchange protocol to build a secure and authenticated communication channel for satellite communication. Our protocol uses identity-based cryptography. We also prove the security of our protocol in the extended Canetti-Krawczyk model, which is the strongest security model for authenticated key-exchange protocols, under the random oracle assumption and computational Diffie-Hellman assumption. In addition, our protocol helps achieve high efficiency in both communication and computation and thus improve security in satellite communication.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.180-183
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• 1997

In this paper, we present the Tele-consulting system of radiology, which uses the communication network as asymetric satellite data communication system. The asymetric satellite data communication system uses receive-only satellite links or data delivery and PSTN(Public Switched Telephone Network) modem or N-ISDN(Integrate Services Digital Network) for communication. The satellite communication linking shows the very high-speed performance than 28.8kbps modem linking. The satellite linking is 5 - 10 times aster than the modem linking. Consequently, we get the conclusion that our system is suitable or tele-radiology and telemedicine.

• Bulletin of the Korean Space Science Society
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• 2006.04a
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• pp.78-78
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• 2006