• Journal of information and communication convergence engineering
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• v.3 no.1
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• pp.13-17
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• 2005

The link e daggregation between 10GbE switches requires an advanced framistribution method to be properly and efficiently applied. The fixed or dynamic frame distribution methods, formerly proposed, cannot fully utilize the aggregated links, where the receiving terminal only attaches to a pre-specified link among multiple physical links. A frame distribution method using padding is proposed for the link aggregation between 10GbE switches to solve this problem. We compared the performance of the proposed method with those of the static and dynamic frame distribution methods. As a result, the proposed method shows a better performance when the offered load is below 0.7 and the average length of the frames is longer than 954 bytes.

• Journal of the Korea Society of Computer and Information
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• v.23 no.12
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• pp.65-72
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• 2018

In this paper, we have studied how to reuse common data link software by applying software product line engineering. Existing common data link software performed different stages of design, implementation, and testing without sharing the accumulated knowledge of different developers. In this situation, developers agreed that sharing the assets of each project and reusing the previously developed software would save human and time costs. Even with the initial difficulties, the common Data Link is a continually proposed project in the defense industry, so we decided to build a product line. The common data link software can be divided into two domains. Among them, the initial feature model for the GUI software was constructed, and the following procedure was studied. Through this, we propose a plan to build a product line for core assets and reuse them in newly developed projects.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.10
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• pp.965-976
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• 2012

Multi-Platform Image and Intelligence Common data link(MPI-CDL) systems are designed to transmit the imaginary and signal intelligence data at an aeronautical to ground line of sight(LOS) link. This paper proposes a method to predict a link availability and analyzes the required link margin to satisfy a given link availability for MPI-CDL systems. To estimate a link availability the proposed method applies the conditional probability so that both a rain attenuation and a multipath fading are considered simultaneously. Link margins to meet the link availability for MPI-CDL systems are calculated according to an operating environment including frequencies, flight altitudes and transmission ranges. The required link margins for actual unmanned air vehicle systems are also given by simulation results.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1338-1341
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• 2004

In this paper, we have proposed a new approach of routing and wavelength assignment algorithms, called Possible Available Wavelength (PAW) algorithm. The weight of a link is used as the main factor for routing decision in PAW algorithm. The weight of a link is defined as a function of hop count and available wavelengths. This function includes a determination factor of the number of wavelengths that are being used currently and are supposed to be available after a certain time. The session requests from users will be routed on the links that has the greatest number of link weight by using Dijkstra's shortest path algorithm. This means that the selected lightpath will has the least hop count and the greatest number of possible available wavelengths. The impact of proposed link weight computing function on the blocking probability and link utilization is investigated by means of computer simulation and comparing with the traditional mechanism. The results show that the proposed PAW algorithm can achieve the better performance in terms of the blocking probability and link utilization.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.4B
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• pp.278-287
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• 2012

In this paper, we propose an allocation scheme for variable message packings to increase efficiency of military operation using Link-16 which is well-known for tactical data link by delivering imagery information rapidly. We propose a variable message packing scheme using COC waveform to support variable data rate under some coverage limitation. Variety of message packing makes Link-16 vary transmission rate appropriately for tactical environment. We also propose a allocation scheme to assign message packing to time slot properly. Finally we verify the performance and superiority of proposed ideas by simulations.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.2
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• pp.187-196
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• 2021

The Network-Centric warfare over weapon data link networks has been developed for the recent decade. Since the US navy had begun to develop tactical digital information chain, it has gradually transformed into weapon data link technology. As data link network system and its protocol have been advanced into high-technology, focusing and targeting on moving targets become possible in net-enabled environments. However, it is difficult to identify the primary information from numerous battlefields and understanding approaches to damage a target in a timely manner. In this paper, to better understand the targeting assessment, we suggest a specific solution: Bomb Hit Indication(BHI) using information in weapon data link messages. In order to prove our suggestion, we implement the BHI solution and apply it into the weapon data link integrating system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.10
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• pp.1194-1199
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• 2010

In this paper, for a relay-based cellular network, a interference avoidance beamforming technique is proposed to enhance direct link capacity while minimizing loss in the capacity of concurrent relaying link. A direct link is transmitted by beamforming at the transmitter, and the relaying link with the least interference to the direct link is scheduled to transmit data by a collision avoidance scheduling algorithm. Simulation results show that the proposed IA beamforming provides a considerable direct link capacity enhancement while minimizing relaying link capacity loss by effectively mitigating inference between concurrent direct and relaying links only with limited feedback.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.2A
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• pp.66-79
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• 2005

In this paper, we have performed the analysis of RF transceiver system and communication link for the improvement in reliability of Smart-UAV(Unmanned Aerial Vehicles) Data-Link. The system analysis performed using the development specification of the data link and data sheet of using components through the system simulation tool that is Agilent EEsof ADS. Also, the communication link analysis peformed using a variety of propagation models for the smart UAV operation environments. As a result, we have presented problems appeared in the simulation results and development specification. As well as, we have presented about several problems and consideration issue for system design through the communication link analysis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.738-746
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• 2016

As the trend of future war has been changed to network centric warfare, tactical data link should be needed for fast and accurate situation awareness. Nowadays, Korean air force conducts military operations by using aircrafts equipped with Link-16. The Link-16 can conduct multiple mission at the same time because it supports multi-net capability. Due to lack of frequency resource, the way to share the frequency with other systems has been studied and using L band with radar is considered as one of the candidates bands. However, the data link can be affected by the interference from radars when it shares the L-band because the L-band in Korea is already assigned to long-range detection radars. In this paper, we evaluate operational possibilities of tactical data link in the L-band based on Link-16.

• Journal of Communications and Networks
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• v.10 no.3
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• pp.331-337
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• 2008

In this paper, we investigate survivability in wavelength division multiplexing (WDM) mesh networks and propose a new algorithm called improved shared-path protection (ISPP) to completely tolerate the double-link failures. Compared with previous algorithms for protecting double-link failures, i.e., shared-path protection (SPP) and shared-link protection (SLP), the advantage of ISPP is to allow primary paths and backup paths to share the mixed wavelength-links based on the proposed new rules in which some primary wavelength-links can be changed to mixed wavelength-links, which can be shared by primary paths and backup paths. In addition, some mixed wavelength-links also can be shared by different backup paths for saving resources. Simulation results show that ISPP algorithm performs better in resource utilization ratio and blocking probability than conventional SPP and SLP algorithms.