• ETRI Journal
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• v.34 no.1
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• pp.122-125
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• 2012

A video signal through a high-density optical link has been demonstrated to show the reliability of optical link for high-data-rate transmission. To reduce optical point-to-point links, an electrical link has been utilized for control and clock signaling. The latency and flicker with background noise occurred during the transferring of data across the optical link due to electrical-to-optical with optical-to-electrical conversions. The proposed synchronization technology combined with a flicker and denoising algorithm has given good results and can be applied in high-definition serial data interface (HD-SDI), ultra-HD-SDI, and HD multimedia interface transmission system applications.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.11
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• pp.123-129
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• 2011

In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=$10^{-9}$ in proposed adverse atmospheric conditions.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.400-401
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• 2013

Mobility in a network causes link disconnections and link recovery is vital for reliability of a network. A link failure affects all the preceding nodes on a damaged routing path; creates communication delay, throughput degradation, and congestion. This paper proposes link recovery mechanisms in CCN based networks. Packet overhearing is used to update neighboring nodes information. The recovery is done by forwarding node resulting in low control overhead, and better efficiency. The proposed mechanisms increase overall performance of a typical CCN and simulation results show that our proposed scheme works very well in densely populated networks with high mobility.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.2 s.7
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• pp.23-31
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• 2005

ITS(Intelligent Transportation System) implementing information collection services and information support services for cars of moving fast needs a communication system of special aim such as RF-DSRC(Radio Frequency Dedicated Short Range Communication). Before RSE(Road Side Equipment) and OBE(On-Board Equipment) will be able to communicate RF-DSRC, OBE first have to request Link Initialization Access using ACTC(Activation Channel) in allocated ACTS(Activation Slot) by Slotted ALOHA. Even though Link Initialization Access is a important element to decide performance of communication system, optimal mathematic modeling study of Link Initialization Access which is adapted RF-DSRC characteristics is not enoush. So, in this paper, we propose mathematical modeling about Link Initialization Access of RF-DSRC. And then we computed Link Initialization Access probability defining offer load(G) which is adapted RF-DSRC characteristics for analyzing performance of modeling.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.93-97
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• 1987

In this paper the data link control procedures for the TDX-1 ESS had been designed and implemented in accordance with the CCITT recommandation X.25 LAPB After a general discussion on intermational standards of link montrol procedures the TDX-1 data link control procedures are described in detail.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1990-1998
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• 2017

The success of naval operation prioritizes the implementation of a robust communication network that delivers accurate and prompt communications to one another. The satellite, which is the main communication network of the military, is required to construct a preliminary communication network because of the enemy radio disturbance and weak point of fixed antenna. The military operational communication network has been in transition from voice-centered wireless communication network to text message-based communication network. In this paper we suggest an enhanced communication method built on Roll Call, the main communication method of ROK Navy operating tactical data link called Link-11. Simulation results display that the proposed method reduces the transmission time per unit frame by 4.3 times compared to the Roll Call and 6.3 times compared with the Round Robin & Broadcasting; it is also proved that the higher the direct reception rate, the shorter the transmission time required by 1.6 times maximum.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8B
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• pp.674-682
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• 2003

This paper presents the studies on wireless channel modeling and reverse link synchronization of CATV. This paper analyzes multi-path fading channel to the cause of signal distortion in the wireless communication environment. We represent the microwave link characteristics according to the channel model. Multi-path channel can affect fading.

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.316-319
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• 2003

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.394-396
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• 2017

In various types of UAV systems, which have been developed recently, the communication system that is responsible for the connection between the ground control unit and the UAV is called the data link.Especially, in the data link used in systems for transmission of surveillance images from UAV in real time, stability of communication should be ensured. In this paper, the design of the data link modem was proposed for the purpose of applying for UAV for surveillance. And, the designed wad verified through the performance measurement of the implemented systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.1
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• pp.106-113
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• 2014

This work proposes an analytic framework to estimate the capacity of the link in an M2M gateway that multiplexes a massive number of machine type communication devices. First, we specify the network architecture for M2M communications. Next, we summarize the characteristics of M2M traffic, from which we extract an area about the problem that has to be resolved in the dimensioning of the link capacity. After that we propose a new method to determine the capacity of the link in an M2M gateway. Via numerical experiment reflecting the realistic environment of M2M traffic, we illustrate the validity of the proposed model.