• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권1호
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• pp.9-16
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• 2005

Accurate and reliable tracking of train is essential for the train control system. The fixed block system which utilizes track circuit has been used widely for the detection of train position. As an alternative, the moving block system has the advantage over the fixed block system since it enables shorter headway and easier maintenance. This paper presents a new technique for the train tracking system which uses radio signal for the train position detection. The proposed algorithm uses the phase difference of arrival of radio signal for the detection of train position. Experimental verification of the algorithm is presented in the paper.

• 한국철도학회논문집
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• 제8권3호
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• pp.244-252
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• 2005

Accurate and reliable tracking of train is essential for a train control system. The fixed block system which utilizes the track circuit has been used widely for detecting train position. As an alternative, the moving block system has the advantage over the fixed block system since it enables shorter headway and easier maintenance. This paper presents a new technique for the train tracking system which uses radio signal for the train position detection. The proposed algorithm uses the phase difference of arrival of radio signal for the detection of train position. Experimental verification of the algorithm is presented in the paper.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.176-176
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• 2000

Generally, discrete-time processing is applied to the uniformly-sampled signals. But, radars emit pulse trains with irregular time instances. In this paper, we formulate the radar pulse train as a stochastic discrete-time dynamic linear model. The estimation task can be done via linear signal processing using Kalman Filter and some considerations. As a result, we can estimate the pulse repetition interval of a pulse train and predict the time instances of the next pulses to be received.

• Journal of information and communication convergence engineering
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• 제6권3호
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• pp.239-244
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• 2008

Cargo tracking issue on train transportation is challenging area because of long distance haulage, theft, terror attack and customer service. This paper aims at evaluating various cargo tracking systems in terms of cost and technology. The contents of this paper consist of the research trend of cargo tracking system in the railroad transportation and reviewing of technical alternatives in cost and service side. GNSS and RFID are reviewed as location tracking technology, Internet and Satellite technology like INMASAT and Low Earth Orbit are also reviewed as communication infrastructure. This paper selects cost and service factors in two alternatives of GNSS-Satellite and RFID-Internet, among GNSS-Internet, GNSS, Satellite, RFID-Internet, RFID-Satellite and evaluate each alternative in terms of cost and service. In a result, in terms of cost, RFID-Internet type is superior to GNSS-Satellite type, but in service GNSS-Satellite type is preferred to RFID-Internet in point of area coverage and service coverage.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1680-1684
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• 2010

CBTC(Communication-Based Train Control) system which is based on wireless communication can provide high density operation of the train using location tracking between ground and onboard train. It can also reduces maintenance expense because it does not require the ground equipment for tracking circuit and signal flag and so on. Recently, research and interest have been done on CBTC system. The high-speed trains up to 300km/h experience multi-path fading channel which bring about the performance degradation of wireless CBTC system. In this paper, we consider MIMO (Multi-Input Multi-Output) antenna-based CBTC system for trains with Alamoutip-type space-time diversity transmission for reliable communication. Also we model a channel considering practical environment and evaluate performance improvement of proposed CBTC system.

• 한국산학기술학회논문지
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• 제17권1호
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• pp.1-8
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• 2016

본 논문에서는 GPS를 이용할 수 없는 지하철 승강장에서 움직이는 지하철의 위치 추적 정확성을 높이기 위해 WiFi 핑거프린트 기법에 k-nn기반 알고리즘들을 적용한 후 오류를 검출하고 비교하였다. 승강장내 지하철의 위치 정보는 지하철 제어를 위해 종합사령실에서 필요로 하며, 이용객의 안전과 편의를 위해 다양하게 사용되어지고 있다. 현재 역사 또는 승강장 내에는 승객의 편의를 위해 각 통신사별로 WiFi용 AP(Access Point)들이 다수 설치되어 있어 이를 활용한 다양한 위치 추정 연구들도 활발히 진행되고 있다. 본 연구에서는 설치되어진 WiFi용 AP를 활용할 경우와 신규로 WiFi용 AP를 설치할 경우등을 고려하여 다양한 조건에서 지하철의 위치를 추적할 수 있는 시뮬레이터를 개발한 후 모의실험을 진행하였다. 개발된 시뮬레이터는 설치된 WiFi용 AP들의 개수와 승강장 넓이, 지하철 진입속도 등에 따라 지하철의 위치를 추적할 수 있도록 설계되었다. 그리고 k-nn알고리즘과 fuzzy k-nn알고리즘을 선택적으로 적용할 수 있으며 핑거프린트 데이터베이스를 기반으로 4가지의 거리 측정 알고리즘을 적용하여 위치 추적 오류를 비교할 수 있도록 하였다. 시뮬레이터를 이용한 모의 실험결과 0.5m의 그리드 단위길이에 8개의 WiFi용 AP를 설치하고 'minkowski' 거리 측정 알고리즘을 적용한 k-nn알고리즘를 사용할 경우 가장 정확한 위치 추적결과를 얻을 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.915-921
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• 2005

Accurate and reliable tracking system is essential for the central train control system. There are two systems widely being used. one is the fixed block system which utilizes the track circuit for the detection of train position. the other is the moving block system which has the advantage over the former since it enables shorter radio signal for the train position detection. In this paper a new algorithm is proposed which uses signal's phase difference of arrival to detect the train position. Experimental verification of the algorithm is presented in the paper.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.953-957
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• 2005

Light Rail Transit(LRT) Systems with transport capacity between subway and bus(5,000-25,000 persons per hour) are being carried on over 100 lines around the world. In Korea, to solve the urban transportation problem, the introduction of LRT system has been proceeded positively. It is planned to develop the Korean standard LRT system in which safety, efficiency and cost effectiveness are emphasized. So we were able to make proto type of Rubber tired AGT system for LRT. This is capable of driverless operation using CBTC(Communication Based Train Control) of Moving Block System and is currently making an experiment for reliability in test-line. This study is focused on verifving the train tracking with CBTC in driverless and ATO mode through implementing the examination.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2292-2299
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• 2011

The CBTC(Communication Based Train Control) system, a recent train control system, is a wireless communication based train control system that is operated in the moving block system control by tracking trains in real time. In additioin, the system helps to increase the volume of traffic by shortening driving headways through controlling moving block system control. Furthermore, driverless modes are performed by controlling ATP(Automatic Train Protection)/ATO(Automatic Train Operation). In this paper, controllable elements in ATO driverless train control system, affecting comfortable ride, will be analysed and applied to CBTC train control system that developed by POSCO ICT. Finally, the test results of improved comfortable ride will be showed by appling the developed system to the Gyeong-san light rail transit test track.

• 한국철도학회논문집
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• 제10권6호
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• pp.633-639
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• 2007

본 연구에서는 RFID 기술을 적용하여 이동하는 철도 화차를 인식하는 최적의 조건을 도출하였다. 이동하는 철도 화차를 인식하기 위해서는 주파수 대역의 선정, 안테나의 각도, 이동하는 속도, 태그의 부착위치 등의 고려해야할 요소들이 있다. 그래서 이동하는 철도 화차를 최적으로 인식하는 조건을 도출하기 위하여 주파수 대역은 900MHz/2.45GHz대역을, 안테나의 각도를 0, 30, 45, $60^{\circ}$로, 이동속도 10/30/50km로, 태그의 부착위치를 3부분으로 나누어 실증 테스트하였다. 그 결과 이동하는 철도 화차를 인식하기 위한 최적의 조건을 실험을 통하여 검증하였다. 따라서 철도물류의 위치인식(Location Detection)과 추적(tracking)을 실시간(Real-time)으로 모니터링 할 수 있으며, 나아가 일반 철도에도 적용하여, EURO-Balis 처럼 철도차량을 검지, 추적 등 철도 신호에 적용될 수 있을 것이다.