• Journal of Ubiquitous Convergence Technology
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• v.2 no.1
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• pp.51-55
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• 2008

A digital home is a ubiquitous environment that is expected to be realized in the near future. All information appliances in a house are connected to each other through wired and/or wireless home networks. Authenticated user can access the various services provided by the digital home, and the access is not restricted by equipment, time, or location. The technologies that form the digital home can be grouped into two categories: wired networking technologies and wireless networking technologies. For the purpose of ubiquitous environments, wireless-networks offer suitable and seamless high-quality services. A wireless LAN can be created simply by equipping a single access point. For that reason, the cost of establishing such a network is low and using it is easy. Of course, there is an exciting new wireless technology. It is the Ultra Wide Band (UWB). However, it is not enough to bring wireless convenience, although offering a broad range of high-speed data transfer capabilities, Because of unstable. Thus, of the wireless-networking systems, we focus on the wireless LAN. We quantitatively analyze its capabilities. The dynamic and adaptive wireless LAN provides a foundation for the evolution toward the next generation of wireless and adaptive networks. The difference between wired LAN and wireless LAN in upload and download rates is small. Although the wireless LAN experiences a greater loss rate than the wired LAN, the difference is minimal. We conclude that a wireless LAN is suitable for use in an apartment environment.

• Information Systems Review
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• v.13 no.2
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• pp.43-54
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• 2011

The paper presents the technology trajectory of competitive wireless technologies in wireless industry. We attempt to trace the trajectory of wireless technologies with historical data, and then analyze its pattern. As a preliminary result, we find that there exists network effect and substitution effect in the trajectory. Our result can provide insight to wireless service providers where best to focus its efforts for maximizing overall gain in their networks as well as when to establish the transition strategy towards the next generation wireless network technologies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.59-60
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• 2015

Wireless power transfer is a technique that supplies the necessary power to the various electronic devices over the air without wires. The technology is classified as near-field wireless power transfer technology using inductive coupling and far-field wireless power transfer technology using antenna. In this paper, RTLS tag for high-precision positioning and wireless power transfer module was designed in order to solve the power supply problem for facility management. was designed for high-precision positioning is possible RTLS tags and wireless charging. The wireless charging pad provides the capability to charge up to four devices using he magnetic resonance system.

• Electronics and Telecommunications Trends
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• v.36 no.4
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• pp.23-33
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• 2021

Wireless communication for train control is an active research field. The World Railway Federation in Europe developed GSM-R, which integrates the GSM-based voice call standard and train control signals. To provide advanced railway services, the LTE-R wireless communication system was developed in Korea for passenger services and wireless image information required by the railroad industry. Recently, direct communication technology for autonomous train driving has been studied to decrease the driving interval, and research is being conducted on a hyperloop train control system that runs at a maximum speed of 1,220km/h in a subvacuum environment of 0.001 atmosphere. In this paper, we summarize the trends in wireless communication technologies used for GSM-R/LTE-R railway systems. For future wireless communication in railway systems, we discuss autonomous train driving and the hyperloop railway control system, define wireless communication technology, and discuss trends in domestic and foreign technologies.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.813-821
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• 2017

This paper presents the study result on a realization of wireless umbilical device for missile systems. In general, a missile system is connected to a fire control equipment via an umbilical connector to get the electrical power for its internal equipment and communicate with each other. And these connectors inherently have many problems of mis-contact between pin and socket, and mis-separation during missile firing, etc. A wireless umbilical device using LC resonance is devised to solve these problems of the current technology. For hundreds of watts power transmission under the missile system environment of restricted space, we designed and made a prototype of wireless umbilical device. And we tested this wireless umbilical device with an aluminum cylinder having cutout windows which simulate missiles. We realized that the wireless technology can be used as a substitute for the conventional umbilical connectors, and EMI and environment tests should be followed further.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.5
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• pp.1077-1093
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• 2013

This paper proposes a new network coordinator node design to select the most suitable wireless technology for WBANs by using fuzzy logic. Its goal is to select a wireless communication technology available considering the user/application requirements and network conditions. A WBAN is composed of a set of sensors placed in, on, or around human body, which monitors the human body functions and the surrounding environment. In an effort to send sensor readings from human body to medical center or a station, a WBAN needs to stay connected to a local or a wide area network by using various wireless communication technologies. Nowadays, several wireless networking technologies may be utilized in WLANs and/or WANs each of which is capable of sending WBAN sensor readings to the desired destination. Therefore, choosing the best serving wireless communications technology has critical importance to provide quality of service support and cost efficient connections for WBAN users. In this work, we have developed, modeled, and simulated some networking scenarios utilizing our fuzzy logic-based NCN by using OPNET and MATLAB. Besides, we have compared our proposed fuzzy logic based algorithm with widely used RSSI-based AP selection algorithm. The results obtained from the simulations show that the proposed approach provides appropriate outcomes for both the WBAN users and the overall network.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.82-86
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• 2001

This papers deals with feasibility study of wireless motion control. Wireless telecommunication advances with development of IT technology and extends more and more areas. So we selected Bluetooth out of the technologies(Bluetooth, SWAP(SharedWireless Access Protocol), IrDA(Infra Red Data Association), WLAN(Wireless Local Area Network)) which was developed for local data communication and set up simple experimental system for wireless data transfer and server and client program for wireless data transfer was wrote. We successfully transferred some data wirelessly with this program.

• Journal of Power Electronics
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• v.19 no.3
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• pp.827-834
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• 2019

Wireless power transfer via coupled magnetic resonances has been a hot research topic in recent years. In addition, the number of related devices has also been increasing. However, reverse signals transfer is often required in addition to wireless power transfer. The structure of the circuit for a wireless power transfer system via coupled magnetic resonances is analyzed. The advantages and disadvantages of both parallel compensation and series compensation are listed. Then the compensation characteristics of the inductor, capacitor and resistor were studied and an appropriate compensation method was selected. The reverse signals can be transferred by controlling the compensation of the resistor. In addition, it can be demodulated by extracting the change of the primary current. A 3.3 MHz resonant frequency with a 100 kHz reverse signals transfer system platform was established in the laboratory. Experimental results demonstrate that wireless power and reverse signals can be transferred synchronously.

• The Journal of Society for e-Business Studies
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• v.13 no.2
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• pp.195-212
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• 2008

The demand of wireless communication system is increasing due to the development of computers and other digital media appliances. In particular, new wireless communication technology is necessary for implementation of home network since a lot of data transmission is occurred. Recently, two wireless communication technologies, Ultra Wide Band(UWB) and 60GHz band wireless communication technology, have being developed for high-speed data transmission and Wireless Personal Area Network(WPAN). In this paper, we study the present development condition of these two technologies and a role of them in home network. We also suggest the method to implement the home network using all wireless communication technologies. At the end, we outlook the market of WPAN and High Definition Multimedia Interface(HDMI).

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.7
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• pp.49-54
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• 2017

In this paper, we propose magnetic field wireless power transfer antenna using Ferrite. It is possible to transfer magnetic field wireless power without independent ground by using characteristic of ferrite in the point that conventional magnetic field wireless power transfer was possible with independent grounding. Ferrite has a shielding effect of magnetic field and reduces leakage power, thereby improving transfer efficiency. We propose an antenna for magnetic field wireless power transfer using ferrite and confirmed that it is transmitted by 5W magnetic field wireless power through experiments. The wireless power transfer proposed in this paper can be applied variously to the Internet of things by using the magnetic field wireless power transfer through the metal.