• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.758-763
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• 2005

Currently, the communication between land and sea using Inmarsat terminal can communicate telephone, telex, fax, e-mail, data transmission. The exist e-mail program between land and sea has developed to reduce communication fee because of high satellite communication coast and low speed. In case of fax service has defect of paper, out-time, high cost. In this paper, we describes the design of fax service system based on Internet for land and sea. This fax system has been integrate e-mail system function and existing fax system function. For this purpose, the hardware module has connect e-mail system and PSTN.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.5
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• pp.129-133
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• 2019

Frequency resource efficiency is important in satellite communication systems. One of the causes of a waste of frequency resource is bad flatness. In the case, flatness of satellite Tx terminals would be worse by ACI and guard band. In order to overcome this problem, this paper proposes a technique for frequency response equalization in satellite Tx terminals. First of all, a general linear polynomial expression which meets least squares of representative measurement data is calculated to interpolate unmeasured data. And then flatness can be adjusted using the polynomial expression. Simulation results illustrate adjusted data have lower peak to peak and standard deviation than original data, and these show that flatness be improved.

• Journal of Satellite, Information and Communications
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• v.11 no.3
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• pp.100-103
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• 2016

This Study is focused on hedonic model study for retargeting advertising Based air inteface using useful information. many research related to the existing Internet of things, relatively not many study for effective advertising model based air inteface. So, this study is designed more information, fun, interactive advertising model based air inteface. therefore, result of this study show that implication to produce advertising based air inteface provides a practical guide.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.215-220
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• 2013

In this paper, the signal reception environment of the satellite communications was analyzed on urban, suburban and rural environment. The correct analysis of received environment is very important in the satellite communications because the presence of various attenuation factors. Analyze attenuation factor through the simulation and that apply to each receiving environment. The urban and suburban various received sensitivity is determined according to building height and density. Moreover, attenuation occurs in rural areas due to the mountainous and vegetation. In this paper, we analysis of variety receiving environment according to movement of the ground station and the satellites can be utilized to provide stable multimedia services.

• Review of KIISC
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• v.8 no.3
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• pp.83-104
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• 1998

인터넷의 급속한 확산과 전세계 통신서비스의 확장으로 인해 세계는 정보의 공유와 다양한 삶의 변화를 가져오고 있다. 교통수단의 발달로 전세계가 일일생활권에 접어들었다면 인터넷과 통신수단의 발전으로 인해 세계는 동일문화권을 형성하고 있다. 주체할 수 없이 수많은 정보와 서비스속에서 사고 있지만, 아직도 좀더 편리하고 안전한 정보의 공유와 윤택한 삶을 영유하기 위한 많은 문제점이 있으며, 이러한 발전 속에서 더 많은 문제점들이 나타나고 있는 것이 현실이다. 또한 이러한 문제점들을 해결하기 위한 다양한 해결책들이 쏟아져 나오고 있다. 본 고에서는다루게 될 내용은 전체적인 공개키 기반구조를 살펴보고 이를 디지털 위성방송 한정 수신 시스템에 적용한다. 공개키 기반구조에 대해서는 인터넷에서 사용자를 인증하기 위한 X.509 인증서에 대해 살펴보고, 인증서를 이용한 서비스에 대해 살펴본다. 또한 최근 각 나라별 공개키 기반구조 표준안의 진행 상황을 알아보고 IETF PKIX 표준안으로서 공개키 관리 프로토콜, CRL CRL 확장, 인증서, 그리고 인증서 확장에 대해 살펴본다. 곧 실현될 디지털 위성방송의 유료화 서비스는 가입자 인증과 서비스에 대한 접근 통제가 가능해야 한다. 따라서 가입자에 대한 관리부분에 공개키 기반구조를 적용함으로써 가입자에 대한 인증과 서비스 및 접근 통제를 가능하게 한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.12
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• pp.85-91
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• 2004

The land mobile antenna for two-way communication using geostationary satellite consists of a transmitting and receiving systems. The transmitting system plays the role of sending the signal to the satellite while the receiving system does the role of receiving signal from the satellite and tacking the target satellite. Especially, the land mobile antenna for satellite communication must be met with the international regulation such as antenna pattern, transmitting power and tracking error to protect the damage of the neighbor satellites. On the other hand, this paper thoroughly examined a receiving system to satisfy a stable satellite tracking performance and antenna pattern specified by the international regulation for Ku-band geostationary satellite.

• Electronics and Telecommunications Trends
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• v.16 no.3 s.69
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• pp.1-8
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• 2001

전력선 이용 통신(PLC)은 전화선, CATV 망, 위성에 이어 제4의 통신망 산업으로 급부상하고 있다. 본 고에서는 피엘콤 이더넷 PLC를 중심으로 PLC의 기술특성 및 인터넷 접속가격 비교를 통해 국내 PLC 시장을 전망하였다. PLC는 기술적인 측면에서 제한된 전송전력, 높은 부하 간섭, 가변감쇠, 그리고 임피던스 레벨 등의 단점을 가지고 있다. 그러나 속도 및 가격 측면에서는 절대 및 비교우위를 가지고 있다. 따라서 기술적인 문제점들을 해결하여 상용화에 성공할 경우 기존의 인터넷접속 서비스 상품과 경쟁하는 제3의 유선통신망으로 등장하면서 기존 통신서비스 시장의 구도를 크게 바꾸어 놓을 것으로 전망된다.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.99-108
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• 2020

In this paper, we analyze the most suitable RA method among PAMA, DAMA, and RA classified by the multiple access method of satellite communication in the rapidly changing traffic environment according to the emergency and tactical situation. It suggests an alternative to improve the limit of output degradation. Based on the CRDSA protocol selected as the standard of DVB-RCS2 among the current satellite communication methods, CRDSA2R (Contention) maintains an optimal RA channel environment by checking the limitations in an environment where packet volume is rapidly increasing and observing channel load and channel conditions. We propose a Resolution Diversity Slotted ALOHA with Adaptive Random Access.

• 한국정보통신설비학회:학술대회논문집
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• 2004.08a
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• pp.177-180
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• 2004

이제는 유비쿼터스이다. 초고속 인터넷이나, 휴대이동전화는 신규 가입자를 확보하기가 쉽지 않다. 이미 시장은 포화 정점에 머물러 있다. 새로운 시장 또는 서비스를 찾고 있으며, 이의 화두는 통합과 유비쿼터스이다. 위성 DMB, 휴대인터넷, 양방향 디지털 방송, 무선 랜 등등... 여기서는 Indoor AP를 이용한 무선랜 서비스를 Outdoor 용 Smart AP를 통해 확산을 꽤 하고자 한다.

• Journal of Internet Computing and Services
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• v.21 no.6
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• pp.1-12
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• 2020

Low-Orbit satellite mobile networks can provide services through miniaturized terminals with low transmission power, which can be used as reliable means of communication in the national public disaster network and defense sector. However, the high traffic environment in the emergency preparedness situation increases the new call blocking probability and the handover failure probability of the satellite network, and the increase of the handover failure probability affects the QoS because low orbit satellites move in orbit at a very high speed. Among the channel allocation methods of satellite communication, the FCA shows relatively better performance in a high traffic environment than DCA and is suitable for emergency preparedness situations, but in order to optimize QoS when traffic increases, the new call blocking and the handover failure must be minimized. In this paper, we propose LEO-DBC (LEO satellite dynamic beam width control) technique, which improves QoS by adaptive adjustment of beam width of low-orbit satellites and call time of terminals by improving FCA-QH method. Through the LEO-DBC technique, it is expected that the QoS of the mobile satellite communication network can be optimally maintained in high traffic environments in emergency preparedness situations.