• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.223-226
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• 2005

본 논문에서는 지능형 교통망 시스템 서비스에 사용하는 5.8GHz 대역에서 OFDM을 이용한 단거리 전용 통신 시스템의 성능을 분석하였다. 현재의 DSRC 시스템은 1Mbps 이상의 데이터 서비스가 어려울 것으로 예상되므로 개선도니 변복조방식이 요구된다. OFDM(orthogonal frequency division multiplexing) 방식은 보호구간의 삽입을 통하여 ISI를 방지할 수 있으므로 고속 데이터 전송에 적합하다. 따라서, 본 논문에서는 데이터 변조 방식으로는 IEEE 802.11a에 근거한 부 반송파의 수가 64개인 QPSK변조 방식을 사용하는 OFDM 시스템을 모델링 하고, 도플러 천이 효과를 고려한 Clark & Gans 페이딩 환경에서 성능을 분석하였다. 또한 페이딩 환경에서는 성능의 열화 정도가 크기 때문에 이를 극복하기 위해 채널 예측기를 사용하여 채널 응답을 근사적으로 예측${\cdot}$보상하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04b
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• pp.1435-1438
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• 2002

미래의 산업으로 부각되고 있는 지능형교통시스템(ITS: Intelligent Transport Systems)은 실시간 데이터의 원활한 전송을 위하여 차량과 노변장치 간의 고속 무선통신 방식인 단거리전용통신(DSRC) 방식을 적용하고 있다. 그러나, DSRC 방식은 실시간 환경에 적합한 축약된 3계층(물리, 데이터링크, 응용계층) 구조로 이뤄져 있으며, 통신영역간에 로밍이나 핸드오프 기능이 결여되어 있어 일반적인 데이터서비스를 제공하기에는 여러 가지 문제점을 안고 있다. 이에, 본 연구에서는 이러한 문제점을 분석하고, DSRC 상에서 효율적인 데이터서비스를 제공할 수 있는 이동에이전트 아키텍처를 제안하였다.

• Journal of the Korean Society for Railway
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• v.4 no.3
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• pp.102-109
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• 2001

In this paper, it has a proposal of the RFID reader antenna design that expand the dedicated short-range communication distance between a static object on the ground and a mobile object attached on the moving article. The static reader equipped with micro-processor makes it possible to have a serial communication with a main system, so that much data can be transfer to the main system. An antenna is adjusted in order to a communication, the scale is designed by results values of simulation using matlab. It is achieved to systematically manage logistics, person resource and security system by grasping the information and location of mobile object on the basis that this system receives the information between a static reader and a mobile object tag at 134.2kHz band on real time, also to make it possible the main system to process. Therefore, the reader antenna scale is controlled on the foundation of a magnetic field theory in order to expand a recognition distance of reader and tag, so that can be optimistically recognized with minimizing the direction influence of reader and tag.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.4
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• pp.345-353
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• 2000

ITS(Intelligent Transportation System) is an advanced system which can effectively handle the current transportation and tragic problems. In order to beneficially apply ITS to the current transportation infrastructure we need a telecommunication technology which guarantees high speed data transmission between the road side units and the on-board units in the vehicles. DSRC(Dedicated Short Range Communication) is considered as a promising technology since it has the capability of two-way communication and can serve to implement various ITS services. In this paper, we study an architecture of telecommunication network far ITS based on DSRC. We use the ISCNA(Information Systems and Communication Networks Architecture) framework for the method of approach. We first analyze the requirements for ITS services using DSRC in Korea, and then establish a logical architecture for the network. We also analyze the types of data and process between the network components. Based on these we propose an architecture for the telecommunication network for ITS. We also briefly discuss the simulation which we perform to validate the proposed network architecture.

• The Journal of the Korea Contents Association
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• v.12 no.9
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• pp.500-511
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• 2012

Recently, use frequency for traffic information which provides shortest paths and traffic condition is increasing. Specially, in the survey, it is shown that users prefer internet portal sites which can be used the most easily among traffic information media. But, there are not many verification systems for traffic information contents of internet portal sites which collect and provide information than traffic information contents which are provided by public service. The purpose of this study is to investigate real accuracy and accuracy felt by users about information provided by portal sites. Therefore, in this research we verified accuracy of information by portal site with real field data and investigate real usage about contents and experienced accuracy by users through survey. Also, users' expectation and satisfaction were surveyed and the contents to be improved were selected by using IPA technique. By the result of accuracy verification by field data using portable DSRC(Dedicated Short Range Communication) devices, it is shown that average error was 14~32% and sometimes very high rate. Also, it is shown that 28.3 % of total respondents prefers the information by portal sites and 50 % of total respondents felt that contents of traffic information by portal sites are not accurate. Real-time traffic condition was selected as the most inaccurate one among all contents of traffic information and it was analyzed that intensive efforts for improving information about real-time traffic condition are needed.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.197-200
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• 2000

지능형 교통 시스템(ITS. Intelligent Transportation System)은 도로, 차량, 신호시스템 등 기본 교통체계의 구성요소에 첨단 정보통신 기술을 접목함으로써 교통시설의 기반구조에 대해 지능화와 첨단화를 꾀하고자 하는 차세대 교통체계로 우리 나라가 처한 교통 환경의 실태와 기존 교통체계의 문제점을 고려할 때 당면한 교통 문제를 해결해 줄 수 있는 유력한 방안으로 여겨진다. ITS는 운전자 혹은 도로 교통 시스템에 각종 응용 서비스를 제공하게 되는데 이를 위해서는 도로변에 위치하는 기지국 등의 ITS 기반 요소들과 도로를 운행 중인 차량간의 빠르고 정확한 정보교환이 가능해야 한다. 정보교환을 위한 통신 기술 중 하나인 DSRC(Dedicated Short Range Communication)는 저출력의 양방향 통신 특성을 갖고 ITS가 제공하는 대부분의 서비스에 다양하게 적용될 수 있으므로 효과적인 ITS의 구축과 빠른 확산을 위해 필수적인 기술로 간주되고 있다. 본 논문에서는 이러한 DSRC를 기반으로 하는 ITS통신망의 구조 정립에 대해 논하고 있다. 효과적인 ITS 서비스를 위해서는 물리적 통신망은 물론 통신망을 구성하고 있는 각 요소들과 관련되어있는 정보시스템들이 동시에 연구되어야 하므로 ISCNA(Information Systems and Communication Networks Architecture) 준거모형에 의한 접근을 하였다. 세부적인 측면으로는 서버 시스템의 구조, 서버와 서버간, 서버와 노변 기지국, 노변 기지국과 차량 단말 간의 통신망 구조 정립에 대해 살펴보았다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.1
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• pp.44-57
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• 2020

A dedicated short-range communications (DSRC) traffic information system is a detection system for a section of road using communication between roadside equipment and on-board High-Pass units to collect road traffic information and provide reliable traffic information to drivers. The Ministry of Land, Infrastructure, and Transport announced that a DSRC system must be supported to pass the performance evaluation of an intelligent transportation system (ITS), and the performance evaluation for DSRC systems installed in expressways and national highways is started. Currently, DSRC traffic information systems are only managed for maintenance and functional-monitoring purposes, which means that detailed criteria for the operation of a DSRC traffic information system, such as communication range, the direction of the antenna, and the power of the radio wave, etc., need to be established. In this paper, the criteria of the performance evaluation of a DSRC traffic information system are presented for different road types and road environments. The proposed performance evaluation criteria included the communication range and communication power of roadside equipment. In addition, installation criteria, such as the direction of the antenna, and the height and angle of the installed system, are presented for different road types and road environments. The criteria presented were evaluated for DSRC roadside equipment and documented to improve system maintenance and quality control of the communication system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.6
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• pp.165-172
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• 2008

The decisive factor for the popularization of telematics services in the future isn the ability to produce advanced service that match the needs of drivers and passengers. The Dedicated Short Range Communication(DSRC)-type of wireless communication system, which is being developed for the Intelligent Transport System(ITS), is one of the broadband wireless systems contributing to the improvement of driver and passenger needs, such as convenience, entertainment, comfort and safety. In this paper, the possibility of applying this system to the traffic information collection service will be explored. Further, a description of the service design for the traffic information collection system using electronic toll collection service will be provided, in the knowledge that the existence of information communication equipment mounted vehicles will remain.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.2
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• pp.393-400
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• 2015

As the development and distribution of the intelligent transport system is spreading recently and some of the services are commercialized through a pilot project, interest in DSRC with high utilization is increasing and antennas for roadside and on board equipment are being studied. A single patch was used for a vehicle antenna due to the requests of miniaturization of size, but there was performance degradation in most cases due to miniaturization. In addition, some methods to improve performance have been used in the antennas that were previously researched using the arrays, but they have the disadvantages of bulkiness in size of the antennas when using the arrays. Therefore, in this paper, the CPW fed microstrip patch antenna with the simple structure of being compact and easy to produce, which can be used in the OBU of DSRC, was designed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.1C
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• pp.8-16
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• 2012

In order for the support of the ETCS (Electronic Toll Collection System) model, which have been operated successfully till now, with multi-lane service, the wireless communication system of the multi-lane-supported ETCS based on RF-DSRC (Radio Frequency - Dedicated Short Range Communication) was used. In this paper, the SME algorithm attaching data flow and form into RFID communication technology was newly suggested to overcome technical problems on RF-DSRC communication system. In addition, in order to verify the SME algorithm, experiments based on ETCS and 900Mhz RFID were carried out. From the result of realization experiment of RFID dependent on the velocity and precision experiment of information inside of RFID, we can see that RFID is detected below 70Km/h and the precision of estimation is more than 90%.