• 제목/요약/키워드: LOS system

검색결과 352건 처리시간 0.026초

무선 비동기식 UWB (WAU) 시스템 구현 (Implementation of Wireless Asynchronous UWB System)

  • 최성수;오휘명;이원태;김관호
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2004년도 하계학술대회 논문집 D
    • /
    • pp.2649-2651
    • /
    • 2004
  • 본 논문에서는 다중객체 인식 시스템과 같은 저용량 데이터전송의 저전력 무선센서네트워크 분야에 적용 가능한 새로운 펄스 방식의 저용량 UWB 통신 시스템을 제안하고 이를 설계 및 구현한다. 특히, 펄스방식의 저전력 UWB 시스템을 구현하기 위해서 전형적인 통신시스템의 수신기 구조인 RF단의 믹서, 상관기와 A/D 변환기를 없애고 최대한 단순화된 구조의 무선 비동기방식의 초광대역 송수신기를 설계한다. 설계된 WAU(Wireless Asynchronous Ultra-Wide band)시스템은 홈내 또는 강의실과 같은 곳에서 1:N HD(Half Duplex) 방식으로 저전력 무선 CANVAS 전송이 가능토록 실제 구현되었다. 구현된 WAU 시스템은 P-to-P(Peer-to-Peer) LOS(Line of Sight) 채널상태의 전송거리 10 m 에서 안정적으로 최대 115kbps 급의 전송속도가 지원 가능함을 측정하였다.

  • PDF

Air-Data Estimation for Air-Breathing Hypersonic Vehicles

  • Kang, Bryan-Heejin
    • Transactions on Control, Automation and Systems Engineering
    • /
    • 제1권1호
    • /
    • pp.75-86
    • /
    • 1999
  • An air-data estimator for generic air-breathing hypersonic vehicles (AHSVs) is developed and demonstrated with an example vehicle configuration. The AHSV air-data estimation strategy emphasized improvement of the angle of attack estimate accuracy to a degree necessitated by the stringent operational requirements of the air-breathing propulsion. the resulting estimation problem involves highly nonlinear diffusion process (propagation); consequently, significant distortion of a posteriori conditional density is suspected. A simulation based statistical analysis tool is developed to characterize the nonlinear diffusion process. The statistical analysis results indicate that the diffusion process preserves the symmetry and unimodality of initial probability density shape state variables, and provide the basis for applicability of an Extended Kalman Filter (EKF). An EKF is designed for the AHSV air-data system and the air data estimation capabilities are demonstrated.

  • PDF

Optical Fiber Y-Branch의 제작과 OTDR 응용 (Optical fiber Y-Branch Fabrication and OTDR application)

  • 이상호;강민호;박한규
    • 대한전자공학회논문지
    • /
    • 제18권3호
    • /
    • pp.21-24
    • /
    • 1981
  • Micro-torch를 사용하여 두 개와 taper를 동시에 제작하고, fusion splicing에 외해 광섬유 t-branch률 제작하였다. Y-branch의 insertion loss는 2.6dB, branching율은 0.98까지 얻을 수 있었다. 또 Y-branch를 OTDR의 제작에 응용하여 광학계를 대폭 간소화 하였으며, 길 이 측정오차 ±5m, 손실 측정오차 ±0.5bB/km로 광섬유의 특성을 측정할 수 있었다.

  • PDF

적외선 호밍 유도탄의 조준축 정렬에 관한 연구 (A Study on the Alignment of Aiming Sight Unit for Infrared Homing Missile)

  • 정영숙
    • 한국군사과학기술학회지
    • /
    • 제7권3호
    • /
    • pp.30-37
    • /
    • 2004
  • For a proper operation of portable air defense IR terminal homing missile to the rapid intruding target, the boresight of an IR seeker of the missile should be accurately aligned with the gunner's aiming sight. Before a gunner fires the missile, he tries to keep the target within the circle of ASU ensuring the seeker to lock on the target correctly. In this paper, using an electrical seeker caging loop and IR detector signal characteristics, a precise aligning method between the seeker boresight and the LOS(Line of Sight) of ASU(Aiming Sight Unit) was studied. Although every seeker has slightly different SLA (Signal of Look Angle) output, we can get negligible alignment error through a fine tuning method of electrical caging signal. This alignment procedure was also adopted in K-PSAM system.

하이브리드 전기자동차용 배터리 ECU 개발 (Development of the Battery ECU for Hybrid Electric Vehicle)

  • 남종하;최진흥;김승종;김재웅
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
    • /
    • pp.740-744
    • /
    • 2003
  • The development of electric vehicle has been accelerated by the recent 'California Initiative' which has required increasing proportions of new vehicle in Los Angeles area to be ZEV(Zero Emission Vehicles) But, because skill of battery is feeble, ZEV regulation was postponed but that is by CO2 restriction and environmental pollution problem the latest because do development require. In the electric vehicle and hybrid electric vehicle, the battery ECU(Battery Management System, BMS) is very important and an essential equipment. The accurate state of charge(SOC) is required for the battery for hybrid electric vehicles. This paper proposes SOC algorithm for the HEV based on the terminal voltage. Also, designed and analyzed battery ECU to apply on HEV.

  • PDF

Scheduling North-South Mirror Motion between Two Consecutive Meteorological Images of COMS

  • 이수전;정원찬;김재훈
    • 한국위성정보통신학회논문지
    • /
    • 제3권2호
    • /
    • pp.26-31
    • /
    • 2008
  • As a multi-mission GEO satellite, Communication, Ocean, and Meteorological Satellite (COMS) is scheduled to be launched in the year 2009. COMS has three different payloads: Ka-band communication payload, Geostationary Ocean Color Imager (GOCI) and Meteorological Imager (MI). Among the three payloads, MI and GOCI have several conflict relationships; one of them is that if MI mirror moves vertically larger than 4 Line Of Sight (LOS) angle while GOCI is imaging, image quality of GOCI becomes degraded. In this paper, MI scheduling algorithm to prevent GOCI's image quality degradation will be presented.

  • PDF

고속철도역 환승시설 서비스 평가지표 개발 및 적용 (The Development and Application of the Service Evaluation Indicators of Transfer Facilities in the High-speed Railway Stations)

  • 김철순;김시곤;김정환
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2008년도 춘계학술대회 논문집
    • /
    • pp.1385-1395
    • /
    • 2008
  • The introduction of KTX(Korea Train Express) has brought an historic change to the overall transit system in Korea. Especially, the high-speed railway stations are expanding the scope as public transit centers. However, we cannot deny that the evaluation on the high-speed railway stations had not been performed successfully so far. The evaluation covers from the connectivity of the scope from door to the stations and the transfer service in the interior of stations. We developed the service evaluation indicators of transfer facilities in the high-speed railway stations. The indicators consist of level of service(LOS), the propriety of allocation, and the quality of information throughout the facilities in the centers. We examined the 7 stations in Korea and standardized the methodology of the evaluation process by applying the indicators. Also, the evaluation is performed easy for anyone to follow.

  • PDF

Status and Prospects of the Utilization of Medicinal Plants in the Philippines

  • Waje, Catherine K.
    • 한국자원식물학회:학술대회논문집
    • /
    • 한국자원식물학회 2005년도 International Symposium & conference of the Plant Resources Society of Korea
    • /
    • pp.11-16
    • /
    • 2005
  • Utilization of herbal medicine has been an intrinsic part of Philippine culture for many centuries. In spite of tremendous development in the field of modern medicine, traditional and alternative medicine will continue to flourish and take an important role in meeting the basic health needs of the people. The National Integrated Research Program on Medicinal Plant (NIRPROMP), the lead government institution for herbal medicinal research had already validated ten medicinal plants and is currently studying new batch of medicinal plants. Five of the ten clinically-tested medicinal plants have been elevated to herbal medicinal drugs that are now being commercially manufactured in the different parts of the country. Research on medicinal plants takes longer time as the nature of medical research dictates it to be. It must adhere to the internationally accepted standards of medicinal research in the Philippines was observed making alternative medicine an effective health delivery system to the people.

  • PDF

실내에서 DS-UWB 시스템의 채널 모델링 및 검증 (The Verification of DS-UWB Channel Model in Indoor)

  • 장필선;권한준;고영은;방성일
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2006년도 하계종합학술대회
    • /
    • pp.43-44
    • /
    • 2006
  • In this paper modeled UWB system transmission channel in apartment environment while furniture and household electric appliance etc. existed. We measured from 10MHz to 16.01GHz by using method of CIR and CTF in both LOS and NLOS environment. Also we design channel model simulator by MATLAB. The Result of Simulation shows BER characteristics by SNR.

  • PDF