• Title/Summary/Keyword: navigation signal

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Extraction of the ship movement information by a radar target extractor (Radar Target Extractor에 의한 선박운동정보의 추출에 관한 연구)

  • Lee, Dae-Jae;Kim, Kwang-Sik;Byun, Duck-Soo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.3
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    • pp.249-255
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    • 2002
  • This paper describes on the extraction of ship's real-time movement information using a combination full-function ARPA radar and ECS system that displays radar images and an electronic chart together on a single PC screen. The radar target extractor(RTX) board, developed by Marine Electronics Corporation of Korea, receives radar video, trigger, antenna bearing pulse and heading pulse signals from a radar unit and processes these signals to extract target information. The target data extracted from each pulse repetition interval in DSPs of RTX that installed in 16 bit ISA slot of a IBM PC compatible computer is formatted into a series of radar target messages. These messages are then transmitted to the host PC and displayed on a single screen. The position data of target in range and azimuth direction are stored and used for determining the center of the distributed target by arithmetic averaging after the detection of the target end. In this system, the electronic chart or radar screens can be displayed separately or simulaneously and in radar mode all information of radar targets can be recorded and replayed In spite of a PC based radar system, all essential information required for safe and efficient navigation of ship can be provided.

RF ENVIRONMENT TEST ON A PROPOSED SITE FOR THE SENSOR STATION OF THE NEXT GENERATION SATELLITE NAVIGATION SYSTEM, GALILEO: II. THE RESULT OF THE TEST ON THE CANDIDATE SITE IN THE YEAR OF 2007 BY KASI AND ESA (차세대 위성항법체계 갈릴레오 센서스테이션 유치 후보지 전파 수신환경 조사: II. 실제 예정 부지에 대한 2007년 한국천문연구원과 ESA 공동조사 결과)

  • Jo, Jung-Hyun;Comte, Michel;Gonzalez, Moises;Park, Jong-Uk;Lee, Chang-Hoon;Park, Phil-Ho;Hwang, Jung-Wook;Choe, Nam-Mi
    • Journal of Astronomy and Space Sciences
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    • v.25 no.1
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    • pp.53-60
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    • 2008
  • A RF environmental field test for the proposed Galileo Sensor Station site was done by Alcatel Alenia technical team contracted by European Space Agency (ESA) and the Space Geodesy division of Korea Astronomy and Space Science Institute at the Korean VLBI Hetwork (KVN) site in Tamla University Campus, Jeju from June 21, 2007 to June 24, 2007. Full band and in-band 24 hour observation for radio frequency interference, precise positioning, and multipath on three proposed antenna locations for Galileo signal were executed. The main purpose of this survey is to verify the results of previous test on 2006 by KASI. The preliminary analysis of the results and a full investigation also had been done by ESA under the permission of KASI until the end of July, 2007.

A Comparison on the Positioning Accuracy from Different Filtering Strategies in IMU/Ranging System (IMU/Range 시스템의 필터링기법별 위치정확도 비교 연구)

  • Kwon, Jay-Hyoun;Lee, Jong-Ki
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.3
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    • pp.263-273
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    • 2008
  • The precision of sensors' position is particularly important in the application of road extraction or digital map generation. In general, the various ranging solution systems such as GPS, Total Station, and Laser Ranger have been employed for the position of the sensor. Basically, the ranging solution system has problems that the signal may be blocked or degraded by various environmental circumstances and has low temporal resolution. To overcome those limitations a IMU/range integrated system could be introduced. In this paper, after pointing out the limitation of extended Kalman filter which has been used for workhorse in navigation and geodetic community, the two sampling based nonlinear filters which are sigma point Kalman filter using nonlinear transformation and carefully chosen sigma points and particle filter using the non-gaussian assumption are implemented and compared with extended Kalman filter in a simulation test. For the ranging solution system, the GPS and Total station was selected and the three levels of IMUs(IMU400C, HG1700, LN100) are chosen for the simulation. For all ranging solution system and IMUs the sampling based nonlinear filter yield improved position result and it is more noticeable that the superiority of nonlinear filter in low temporal resolution such as 5 sec. Therefore, it is recommended to apply non-linear filter to determine the sensor's position with low degree position sensors.

A Study on the Propagation Environment for VHF Maritime Digital Communications Operation in South Sea Area (남해안의 VHF 해상디지털통신 운용을 위한 전파환경 연구)

  • Ju, Yang-Ro;Kim, Kab-Ki;Choi, Jo-Cheon;Lee, Seong-Ro
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1310-1316
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    • 2014
  • The IMO has recommended on VHF digital communications operation for sailing ships from 2017. And ships more than 5 tons is obliged to digital communications by fishing Vessels Act and Vessel Safety Act in domestic. The owner of all vessel is equipped to the automatic position reporting device in accordance with the Notice of the Ministry of Oceans and Fisheries to regulations, It shall be ensure to navigations safety and in order to respond quickly in the event of maritime accidents on all vessels. The info-communications station of fishery is operating the automatic position reporting system using the VHF DSC in east sea from 2012, Continuously, which is underway the install plan in south sea and yellow sea. But this plan is very difficult, because of propagation environment is poor on account of complicated coastline and many islands. This paper has analyzed the propagation coverage for position setting of coast station in south sea and the traffic zone set up by compare with RSSI and methode of navigation tracking by VMS.

Analysis of PRC regeneration algorithm performance in dynamic environment by using Multi-DGPS Signal (다중 DGPS 신호를 이용한 동적 환경에서의 PRC 재생성 알고리즘 성능분석)

  • Song Bok-Sub;Oh Kyung-Ryoon;Kim Jeong-Ho
    • The KIPS Transactions:PartA
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    • v.13A no.4 s.101
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    • pp.335-342
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    • 2006
  • As PRC linear interpolation algorithm is applied after analysed and verified in this paper, the unknown location of a user can be identified by using PRC information of multi-DGPS reference station. The PRC information of each GPS satellite is not varying rapidly, which makes it possible to assume that PRC information of each GPS satellite varies linearly. So, the PRC regeneration algorithm with linear interpolation can be applied to improve the accuracy of finding a user's location by using the various PRC information obtained from multi-DGPS reference station. The desirable PRC is made by the linear combination with the known position of multi-DGPS reference station and PRC values of a satellite using signals from multi-DGPS reference station. The RTK-GPS result was used as the reference. To test the performance of the linearly interpolated PRC regeneration algorithm, multi-channel DGPS beacon receiver was built to get a user's position more exactly by using PRC data of maritime DGPS reference station in RTCM format. At the end of this paper, the result of the quantitative analysis of the developed navigation algorithm performance is presented.

Effects of Secondary Task on Driving Performance -Control of Vehicle and Analysis of Motion signal- (동시과제가 운전 수행 능력에 미치는 영향 -차량 통제 및 동작신호 해석을 중심으로-)

  • Mun, Kyung-Ryoul;Choi, Jin-Seung;Kang, Dong-Won;Bang, Yun-Hwan;Kim, Han-Soo;Lee, Su-Jung;Yang, Jae-Woong;Kim, Ji-Hye;Choi, Mi-Hyun;Ji, Doo-Hwan;Min, Byung-Chan;Chung, Soon-Cheol;Taek, Gye-Rae
    • Science of Emotion and Sensibility
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    • v.13 no.4
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    • pp.613-620
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    • 2010
  • The purpose of this study was to quantitatively evaluate the effects of the secondary task while simulated driving using the variable indicating control of vehicle and smoothness of motion. Fifteen healthy adults having 1~2years driving experience were participated. 9 markers were attached on the subjects' upper(shoulder, elbow, Wrist) and lower(knee, ankle, toe) limbs and all subjects were instructed to keep the 30m distance with the front vehicle running at 80km/hr speed. Sending text message(STM) and searching navigation(SN) were selected as the secondary task. Experiment consisted of driving alone for 1 min and driving with secondary task for 1 min, and was defined driving and cognition blocks respectively. To indicate the effects of secondary task, coefficient of variation of distance between vehicles and lane keeping(APCV and MLCV) and jerk-cost function(JC) were analyzed. APCV was increased by 222.1% in SN block. MLCV was increased by 318.2% in STM and 308.4% in SN. JC were increased at the drivers' elbow, knee, ankle and toe, especially the total mean JC of lower limbs were increased by 218.2% in STM and 294.7% in SN. Conclusively, Performing secondary tasks while driving decreased the smoothness of motion with increased JC and disturbed the control of vehicle with increased APCV and MLCV.

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