• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.38 no.6
• /
• pp.28-38
• /
• 2001

In this paper, we propose and analyze a more efficient and flexible dynamic data traffic system for a circuit switched satellite network. Our proposed system is more efficient than existing circuit switched satellite networks and allows for dynamic capacity in each connection without rebuilding or resetting the connection software or algorithms. We also discuss an algorithm for bandwidth allocation that provides deterministic quality of service guarantees. The traffic sources are regulated using standard dual leaky buckets; the system performance is analytically evaluated; and the algorithm is verified through simulation. Our analysis scheme and results should prove useful for the design and implementation of protocols in future circuit-switched satellite networks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.7A
• /
• pp.715-724
• /
• 2010

K-water has used satellite networks for 12 years for hydrological observation in various parts such as remote data acquisition and providing information including flood forecasting. It is the time to replace equipments according to long-term use of the system. A pilot system for high speed satellite networks is implemented by seven terminals, three 2-hops and 1 hub in Ku-Band bandwidth by using VSAT. According to the result for the performance test on the system, the result fot all items, including Link Budget designed meets performance levels.

• Proceedings of the IEEK Conference
• /
• 2000.06a
• /
• pp.81-84
• /
• 2000

This paper has been studied a interworking signalling protocol between two hybrid networks by analyzing Satellite B-ISDN architecture, DSS2 Layer 3 Signalling protocol B-ISUP protocol, S-BISUP protocol stack and so on. Also in the paper, messages and primitives have been defined for B-ISDN's Connection Type, Ownership and each protocol in order to connect point-to-multipoint. And then this paper has designed basic call procedures for OBP Satellite B-ISDN NNI inter-working protocol, verified and implemented them.

• IE interfaces
• /
• v.12 no.1
• /
• pp.19-25
• /
• 1999

The time slot scheduling problem for a satellite cluster with an arbitrary number of satellite is considered, which is one of the most interesting problems in the satellite communication scheduling area. This problem is known to be NP-complete, and several heuristic algorithms have been proposed. In this paper, a new efficient algorithm is suggested, which has lower computational complexity and provides much better solution than other existing algorithms.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.2B
• /
• pp.118-123
• /
• 2007

This paper studied the transmission control protocol over IP network to enhance the performance of the GSO satellite communication networks. The focus of this study is how to reduce the long round trip time and the transmission data rates over satellite link in the bidirectional satellite network. To do it, this study applied the caching and spoofing technology. The spoofing technology is used to reduce the required time for the link connection during communication. The caching technology is to improve the transmission bandwidth efficiency in the high transmission data rate link The tests and measurements in this study was performed in the commercial GSO communication satellite network and the terrestrial Internet network. The results of this paper show that the studied protocol in this paper highly enhance the performance of the bidirectional satellite communication network compare to the using TCP/IP satellite network protocol.

• Proceedings of the IEEK Conference
• /
• 2000.11a
• /
• pp.13-16
• /
• 2000

Recently, with the advent of satellite communication technologies, the network access service through satellites has emerged as an alternative to existing ones. Of satellite access services including multimedia services, the high speed internet access service will be one of the important services. Particularly, the efficient transportation of real time internet traffic seems very essential. The aim of this research is to examine the applicability of the IETF RTP protocol in the satellite access network. The RTP has been developed for the QoS-met transportation protocol of real time traffic over the existing best-effort internet. This paper summarizes the RTP protocol, and describes the architecture of the implementation of the RTP. And also, the compressed RTP header protocol is discussed for the applicability to the satellite link.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.42 no.1
• /
• pp.172-180
• /
• 2017

Korean army has been trying to construct a future tactical network in collaboration with TICN at the ground level and the next-generation military satellite system in the space level. However, due to the low bandwidth and high operational cost, the satellite system has the limitation to exchange all kind of tactical information through it. To overcome the limitation, there have been several researches to construct airborne networks. In this paper, we propose an effective interworking architecture and operation scheme between terrestrial tactical networks and aerial relay networks to counteract against the communication breaks of terrestrial terminals. And, we also propose a way to analyze its effectiveness. The experimental results show that the interworking of aerial relay networks can manage the failure situations in terrestrial tactical networks very effectively.

• Journal of computational fluids engineering
• /
• v.15 no.3
• /
• pp.66-72
• /
• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat and utilize several heat pipe networks to control the temperatures of units and the main structures of satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary satellite design stage, so several thousands of nodes or more are utilized in order to perform detailed thermal analysis of panel. Generating a large number of panel nodes takes time and is tedious work because the nodes can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required to generate a detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of the panel thermal analysis program with its main modules and functions.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.25 no.2
• /
• pp.88-99
• /
• 2022

The river network is one of the essential topographical characteristics in river management. The river network which as previously constructed by the ground surveying method has recently begun to be efficiently constructed using the remote sensing datasets. Since it is difficult to remove these obstacles such as bridges in the urban rivers, it is rare to construct the urban river networks with the various obstacles. In this study, the Sentinel-2 satellite imagery was used to develop the automatic method for detecting the urban river networks without the obstacles and with the preserved boundaries as follows. First, the normalized difference water index image was generated using the multispectral bands of the given Sentinel-2 satellite imagery, and the binary image that could classify the water body and other regions was generated. Next, the morphological operations were employed for detecting the complete river networks with the obstacles removed and the boundaries preserved. As a result of applying the proposed methodology to Han River in Seoul, the complete river networks with the obstacles removed and the boundaries preserved were well constructed.

• Journal of Satellite, Information and Communications
• /
• v.2 no.1
• /
• pp.14-20
• /
• 2007

The Korean Military Satellite Communication System (KMILSATCOM) is composed of military payload of KOREASAT 5 and military satellite terminals. The military satellite terminals communicate with each other in satellite service area. The satellite terminal management system is developed for centralized management of satellite terminals and communications link. The satellite terminal management system dose not use terrestrial networks (i.e. Fiber optic, Microwave) for management because the KMILSATCOM is system for emergency (i.e. war time) and the satellite terminals has to move to operational area, so the management link must use satellite link. The management link is composed of 1 to N communication scheme for one manager and multiple terminals. This paper describes the satellite terminal management protocol architecture and the performance of the protocol of the KMILSATCOM system.