• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.147-152
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• 2022

This study describes the design and implementation of EGSE for Dehop/Rehop Transponder. The EGSE is a equipment that evaluates Dehop/Rehop Transponder and requires precise and accurate measurement. EGSE consists of a PLDIU and IIU(Instrument Interface Unit), Up/Down converter for L band, Modems to verify the Dehop/Rehop Transponder. The EGSE was used for performance verification and space environment test such as thermal vacuum after developing Dehop/Rehop Transponder.

• Journal of the Korea Institute of Military Science and Technology
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• v.1 no.1
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• pp.219-226
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• 1998

군 위성통신 시스템의 생존성 향상을 위한 대전자전기능 설계기법으로 Dehop/Rehop 중계기를 사용하는 FH-FDMA 위성통신방식 설계구조를 제안하고 성능을 분석하였다. Dehop/Rehop방식은 적의 재밍조건하에서 필수적 통신링크를 보장하는 설계기법으로 Bent-Pipe방식에서의 Power Robbing, Hard-limiter에 의한 소신호 감쇄 등이 거의 없으며 광대역 도약으로 항재밍 능력의 개선이 가능하다. 본 연구에서는 75bps-2048kbps의 LDR/MDR/HDR 데이터 전송이 가능한 중계기 구조를 설계하고, SHF대역에서 도약대역폭에 따른 항재밍 성능분석과 Bent-Pipe방식 대비 Dehop/Rehop방식의 채널별 항재밍 성능분석결과 9-l0㏈내외의 성능개선이 가능함을 보였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.437-442
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• 2021

This study describes the design and implementation of power supply of dehop/rehop transponder of EQM(Engineering Qualification Model). We materialized the interface of the PLDIU and power supply of a satellite bus, and minimized the potential for the occurrence of such erroneous operation circuit ESD through the WCA of the space environment. We designed a reliable power supply through simulation for TID about space radiation and simulation of the vibration generated during it launched, and we confirmed that it satisfies the environmental test specification through the test space environment after production.

• Journal of Satellite, Information and Communications
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• v.11 no.3
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• pp.104-109
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• 2016

A technology of GEO satellite communications starts from Koreasat program in Korea. Payload equipment of EQM Ku and Ka band transponders had been developed and space-qualified Ka band payload in COMS was successfully launched in June, 2010. For the purpose of military communications, Dehop-Rehop transponder was developed in Koreasat5 as ANASIS system and DAT(Digital Active Transponder) and DCAMP(Digital Channel AMPlifier) transponders are now under development. In this paper, from the study of military satellite communications trend, a direction of military communication satellite is suggested based on the current GEO SATCOM technologies in Korea. Considering the limit of frequency resources, a technology of battlefield adaptive transponder with medium capacity against high moveable jamming tactics would be efficient for the future military SATCOM system. Mid-sized military satellites with frequency hopping and mid-capacity transponders can be a solution of vitalizing the GEO satellite programs.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.6
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• pp.762-768
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• 2016

In this paper, a method for generating ranging signal to reduce the effects of interference and overcome intentional jamming is proposed in slow frequency hopping(SFH) communication system. A terminal uses ranging signal for initial Up-link synchronization in the frequency hopping communication systems using multi-terminal. However, ranging signal generated by unsynchronized terminal acts as an interference signal to another terminal. Therefore, we propose the design of the ranging signal with PN sequence in order to minimize the affection to the other terminal and simulated its performance. From the simulated result, we confirm synchronization performance.