• Journal of IKEEE
• /
• v.26 no.1
• /
• pp.89-94
• /
• 2022

The W-band (75-110GHz) is a band that can utilize at least 10 times more bandwidth than the existing 5G band. Therefore, it is one of the bands suitable for future mobile communication that requires high speed and low latency, such as virtual and augmented reality. However, since the wavelength is short, it has a high path loss and is very sensitive to the atmospheric environment. Therefore, in order to develop a W-band communication system in the future, it is necessary to analyze the characteristics of path loss according to the channel environment. In this paper, to analyze the characteristics of the W-band path loss, the random forest technique was used, and the influence of the channel parameters according to the distance section was analyzed through the path loss data according to various channel environment parameters. As a result of the simulation, the distance has the highest influence on the path loss in the short distance, and the other channel environment factor is almost ignored. However, as the distance section became longer, the influence of distance decreased while the impact of clutter and rainfall increased.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.12
• /
• pp.2210-2216
• /
• 2007

In this paper, triple-band plastic chip antennas for mobile terminal are investigated. Plastic chip antenna is composed of Foamex material with circle of PVC(Polyvilyl chloride). For its electric characteristics, the dielectric constant is 1.9, the insulation intensity is 112KV/cm. Plastic chip antennas are don't tend to break easily against to external shock, have more gain and efficiency than ceramic chip antennas. Triple-band plastic chip antennas of four type are implemented and experimented. From the experiments results, the antenna resonate at the triple-band, the gain of the antennas has about above -2dB, the pattern is ommidirectional the same as the conventional antennas. So, the antennas realized with Foamex material will be application for mobile phone antenna operated at the triple band which is cellular band and Korea-PCS band and ISM band or the antenna for other wireless communication system.

• Journal of IKEEE
• /
• v.27 no.1
• /
• pp.122-126
• /
• 2023

In this paper, a control system for a complex microbial incubator was proposed. The proposed control system consists of a control unit, a communication unit, a power supply unit, and a control system of the complex microbial incubator. The controller of the complex microbial incubator is designed and manufactured to convert analog signals and digital signals, and control signals of sensors such as displays using LCD panels, water level sensors, temperature sensors, and pH concentration sensors. The water level sensor used is designed and manufactured to enable accurate water level measurement by using the IR laser method with excellent linearity in order to solve the problem that existing water level sensors are difficult to measure due to foreign substances such as bubbles. The temperature sensor is designed and used so that it has high accuracy and no cumulative resistance error by measuring using the thermal resistance principle. The communication unit consists of two LAN ports and one RS-232 port, and is designed and manufactured to transmit signals such as LCD panel, PCT panel, and load cell controller used in the complex microbial incubator to the control unit. The power supply unit is designed and manufactured to supply power by configuring it with three voltage supply terminals such as 24V, 12V and 5V so that the control unit and communication unit can operate smoothly. The control system of the complex microbial incubator uses PLC to control sensor values such as pH concentration sensor, temperature sensor, and water level sensor, and the operation of circulation pump, circulation valve, rotary pump, and inverter load cell used for cultivation. In order to evaluate the performance of the control system of the proposed complex microbial incubator, the result of the experiment conducted by the accredited certification body showed that the range of water level measurement sensitivity was -0.41mm~1.59mm, and the range of change in water temperature was ±0.41℃, which is currently commercially available. It was confirmed that the product operates with better performance than the performance of the products. Therefore, the effectiveness of the control system of the complex microbial incubator proposed in this paper was demonstrated.

• Journal of IKEEE
• /
• v.12 no.3
• /
• pp.151-157
• /
• 2008

The DNP3.0 and the IEC61850 are the most important standards in the SCADA systems for the power. Each standard has strength and weakness, so they will coexist for a while. This paper presents a design of the gateway function between DNP3.0 and IEC61850. Both standards use object-oriented modelling methods, so, they have some similarities. However, the DNP3.0 objects are described by object number and index, and the IEC61850 objects are described by name. So there should be mapping function between the object number and index of DNP3.0 objects and the object name of IEC61850 objects. We analyse the communication profiles of both standards, and shows the service-primitive mapping table and the procedure of the gateway function.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.4
• /
• pp.814-819
• /
• 2010

This study proposes the antenna circuit design for the transmitting wireless power, the development of the RF non-contact type Dosimeter. That is, the study designed the optimization and numerical analysis of the antenna circuit for the antenna design of 13.56MHz over the frequency bands for transmitting wireless power. We studied the needed items in the existing RF type Dosimeter with battery to implement the wireless power non-contact Dosimeter within the battery. We compared to the real measurement value as calculating the value of the inductance and capacitance through the numerical analysis for the antenna LC resonance using the theory of the electromagnetic induction method. This method to drive low power is designed to simplify the circuit and to improve the efficiency of the rectifier. We convince our research contributes not only to understand the simplified circuit and miniaturization, but also to help the design and application technology of the wireless power transmit system which is received power supply with wireless.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.657-659
• /
• 2004

CAN is a serial communication bus for real-time controls and automations in distributed control systems. In distributed control systems, occasionally a sensor module and a controller are not in the same node and physically separated. In order for the signal from a sensor node to reach the controller node, the signal must travel through network. CAN has a certain capabilities to deal with real-time data. However, when many nodes on the networks try to send data on the same network, the arbitration mechanism to solve the data collision problem is necessary. This situation causes the time delay which has detrimental effects on the performance of the control systems. This paper proposes a method to solve the problem due to the time delay in distributed control system using CAN. Time delay is approximated to an element with a rational transfer function using Pade approximation and Mu~synthesis method is applied. Since time delay in the network is not constant, the time delay element is considered to be an uncertainty block with a bound. The proposed method is applied to the experimental system with CAN and proved to be effective.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.284-285
• /
• 2011

변전소의 디지털화를 통한 변전소 자동화 시스템(SAS) 구축이 전 세계적 이슈이다. 변전소 디지털화는 기존의 변전소 기능에 정보 통신 기술을 적용시켜 변전소 운영을 효과적으로 수행할 수 있게 돕기 위해서이다. 디지털 변전소가 정상적으로 운영되기 위해 요구하는 높은 수준의 가용성과 전송능력 만족하기 위해 IEC TC 57 WG10은 IEC SC65 WG15의 IEC 62439 고 가용성 자동화 네트워크(Highly Available Automation Networks)를 디지털 변전소 네트워크로 차용하기로 결정했다. 그중 가용성과 신뢰성, 전송능력, 경제성을 이유로 IEC 62439의 중복 네트워크 프로토콜 중 HSR(High-availability Seamless Redundancy)을 디지털 변전소를 위한 네트워크 프로토콜로 이용하기 위한 많은 연구가 진행되고 있다. 특히 디지털 변전소 내부에서도 가장 높은 수준의 가용성과 네트워크 성능을 요구하는 프로세스 버스용 네트워크 구성 프로토콜로 적합하다. 본 논문은 실제 154Kv급 변전소 프로세스 버스에 HSR을 적용하였을 때 성능을 분석하였다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.1
• /
• pp.192-196
• /
• 2010

Due to a development of a modem technology as Power Line Communication(PLC) over 200 Mbps, the high-speed multi-media data trasmission could be currently possible. The strength of the PLC has no more additional wiring work. PLC has also possible to high quality data transmission with currently electrical cable. It has a various strong point campare with existing wire and wireless communication technologies. In This paper we develop a high quality media transmitter-receiver based on merging the HomePlug AV, which is 200 Mbps class PLC technology and HDMI Interface technology. The video function was used for the VEDEO TEST GENERATOR in order to a property valuation. Smart Live 6 software were used for the assessment of audio property. As the result of measurement of the HD class images by capturing from the receiver of the PLC, the quality of images couldn't be confirm any deterioration, which has compared with original reflections. In case of audio part as the result of confirmation of the Phase, Magnitude, it has been confirmed that over 90% of nomal transmition and receiving of acoustic signal. It can be possible to have HD class Media service through the PLC.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.10
• /
• pp.1412-1419
• /
• 2012

In this paper, we propose the protection coordination algorithm using communication methode based on IEC 61850. The communication protocol in power distribution management system has been issued by IEC standard, IEC61850 of them, which was made for substation automation system, has researched to apply into power distribution system, even though the standard is not a suitable for the system. In smart distribution management system' launched in 2009, the communication network based on the ethernet network for IEC 61850 has been designed to apply the self-healing concept, which is to perform the system protection through the communication between remote terminal units(RTU) according to the standard. However, it is first time to apply the scheme in the real. Thus, this paper proposed the protection algorithm and consideration for applying communication method and introduced the result of demonstration.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.3
• /
• pp.443-450
• /
• 2007

We overview the current distribution automation system in Korea and point out the limitations of the distribution services which can be provided by the current system. In this paper we propose a new distribution system architecture which is based on the peer-to-peer communication model. In this decentralized architecture the intelligent FRTUS can initiate data transmission without any interruption of a central server, and can exchange data with other FRTUS as peers. In order to support the peer-based distribution system, we specify the requirements for new communication network and suggest a way of improving the current distribution network where we adapt an intelligent module for protection and restoration, called MASX, and utilize the open communication network protocols. We also show how the new architecture can enhance major distribution services such as protection, automatic restoration, and equipment management.