• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.6
• /
• pp.535-542
• /
• 2011

The Global Navigation Satellite System(GNSS) is being utilized in numerous applications. The research for autonomous guided vehicles(AGVs) using precise positioning of GNSS is in progress. GNSS based AGVs is useful for setting driving path. This AGV system is more efficient than the previous one. Escipecially, the obstacle is positioned the driving path. Previcious AGVs which follow marker or wires laid out on the road have to stop the front of obstacle. But GNSS based AGVS can continuously drive using obstacle avoidance. In this paper, we developed collision avoidance system for GNSS based AGV using laser scanner and collision avoidance path setting algorithm. And we analyzed the developed system.

• Journal of Advanced Navigation Technology
• /
• v.1 no.1
• /
• pp.59-69
• /
• 1997

In this paper, we construct a navigation geography database using R-tree, and develop a software for avionics systems such as VOR, ILS, DME, and NDB. First, we design the navigation geography database using R-tree, and construct a database for navigation aids facilities of every airport. In order to implement avionics software, we develop some calculating algorithms for distance, bearing, and deviation angle between an aircraft and a VOR station for VOR, and deviation angle from a LLZ, glide slope from a GP, and range of markers for ILS. The navigation geography database system is composed of map data manager which can construct and update the database, real-time searcher which provides information about the avionics system, geography database, and user interface.

• Journal of Advanced Navigation Technology
• /
• v.14 no.5
• /
• pp.648-654
• /
• 2010

In this paper, a navigation system was designed, and performance tested in order to confirm the safety improvement of the GNSS(Global Navigation Satellite System)-based AGV(Autonomous Guided Vehicle) which used only position information on of GNSS. We developed DR(Dead Reckoning) navigation system that involve the use of GNSS abnormal positoning error detection and GNSS signal outage. The test results show that GNSS positioning error is detection can be archived with an error of more than 0.15m. In addition, the DR driving position error is 1.5m for an 8s GNSS positioning service outage.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.2
• /
• pp.97-102
• /
• 2019

The GNSS(Global Navigation Satellite System) provides important information such as Position and Navigation, Timing(PNT) to various weapon systems in the military. as a result, applications that employ satellite navigation systems are increasing. therefore, a number of studies have been conducted to deceive the weapon systems that employ GNSS. GNSS spoofing denotes the transmission of counterfeit GNSS-like signals with the intention to produce a false position and time within the victim receiver. In order to deceive the victim receiver, spoofing signal should be synchronized with GNSS signal in doppler frequency and code phase, etc. In this paper, Civilian GPS L1 C/A spoofing signals have been evaluated and analyzed by SDR receiver.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.48 no.6
• /
• pp.401-410
• /
• 2020

In this study, a real-time Tactical UAS position compensation system based on image information developed to compensate for the weakness of location navigation information during GPS signal interference and jamming / spoofing attack is described. The Tactical UAS (KUS-FT) is capable of automatic flight by switching the mode from GPS/INS integrated navigation to DR/AHRS when GPS signal is lost. However, in the case of location navigation, errors accumulate over time due to dead reckoning (DR) using airspeed and azimuth which causes problems such as UAS positioning and data link antenna tracking. To minimize the accumulation of position error, based on the target data of specific region through image sensor, we developed a system that calculates the position using the UAS attitude, EO/IR (Electric Optic/Infra-Red) azimuth and elevation and numerical map data and corrects the calculated position in real-time. In addition, function and performance of the image information based real-time UAS position compensation system has been verified by ground test using GPS simulator and flight test in DR mode.

• Journal of Internet Computing and Services
• /
• v.3 no.6
• /
• pp.35-41
• /
• 2002

The Car Navigation System(CNS) requires lots of memory and calculating time because it works on the large and complex digital map. And the traffic circumstances vary time by time, so the traffic informations should be processed if we want to get mere realistic result. This paper proposes an effective path searching algorithm which uses less memories and calculating time by applying directional information between the starting place and destination place and by using realtime traffic informations.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.11a
• /
• pp.207-208
• /
• 2022

최근 유럽연합은 고정밀 위치정보를 갈리레오 항법시스템을 통해 제공할 계획임을 밝힌 바 있으며, 가까운 일본은 QZSS 지역 위성항법시스템을 통해 자국 영토에 센티미터급 위치정보 서비스를 실시하고 있다. 우리나라 대한민국은 2020년 4월부터 지상 통신 또는 방송망을 이용하여 센티미터 정확도의 위치정보를 해상에 제공할 수 있는 기술 개발을 시작하였다. 본 논문은 현재 진행되고 있는 해당 기술개발과제, '지상기반 센티미터급 해양 정밀 PNT 기술개발'의 연구현황과 함께 연구개발의 배경과 기술개발 동향에 대해 살펴본다. 그리고 마지막으로 고정밀 위치정보 서비스의 미래 모습에 대해 전망한다.

• Journal of Korean Society for Geospatial Information Science
• /
• v.18 no.3
• /
• pp.67-74
• /
• 2010

The aim of this paper is to come up with a methodology of migration for current transportation digital map in order to construct NDRM, which is the most essential map data for car navigation system. The model suggested through our study is able to efficiently produce navigable service map for route finding and guidance as well as to make the best of general road network developed by KOTI.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.101-103
• /
• 2000

본 논문에서는 GPS(Global Positioning System)와 추측 항법 시스템인 DR(Dead Reckoning)을 혼합 구성한 수신보드의 운영을 위한 Embedded 운영체제를 설계하고 구현 하였다. 이 운영체제는 실시간으로 인공위성으로부터 수신되어지는 Raw Measurement 획득, GPS 항법, 자세 결정, 통합항법, 위성 추적을 수행하는 태스크들을 우선순위 기반으로 처리하는 선점형(Preemptive) 스케쥴링 방식을 채택한 실시간 운영체제 이다. 본 논문에서는 자세 결정용 GPS와 DR 센서를 이용한 통합시스템보드를 위한 실시간 운영체제의 개발 환경, 운영체제의 구조와 개발 내용에 대해 언급하였다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2018.07a
• /
• pp.279-280
• /
• 2018

본 과제는 비행체에 자동제어 시스템인 자동항법비행기능을 탑재한 무인기를 제작한다. 자동항법비행이 가능한 무인기는 사람이 직접 조종하는 기존의 비행체들 보다 정밀하고 섬세한 제어가 가능하며 조종자의 시야가 닿지 않는 곳에서의 비행이 가능하다는 장점을 가진다. 또한 상공에서 영상을 촬영하며 5.8GHz대역의 영상 송 수신기를 통한 실시간 영상 확인이 가능하다. 본 과제는 GPS를 이용한 프로그래밍을 통해 미리 지정한 좌표를 따라 비행이 가능하며 실시간 영상 수신이 가능하기 때문에 사람이 직접 갈 수 없는 오염된 지역 등의 정찰이 가능하고, 비행체에 장착되는 장비에 따라 군용, 소방용 등의 다양한 범위에서의 활용이 가능할 것으로 예상된다.