• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.3
• /
• pp.215-221
• /
• 2009

In this paper, a slotted trapezoidal microstrip fractal patch antenna is designed and fabricated for the vehicle GPS antenna. We designed air substrate patch antenna to obtain gain improvement by the elimination of dielectric loss. By applying fractal structure with crossed slot to trapezoidal patch, we obtained 42.5 % as much patch size as conventional triangular patch antenna. Measured bandwidth was 200 MHz on GPS band under VSWR 2:1 And gain was 4.31 dBi at resonant frequency that is 2$\sim$5 dB higher gain than conventional ceramic patch antenna on GPS band.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.18 no.4
• /
• pp.432-440
• /
• 2015

UGVs(Unmanned Ground Vehicles) are robots that can substitute humans in reconnaissance operations of potentially dangerous and contaminated sites. Currently, there have been active research on utilizing UGVs in military environments. Much resrach has been focused on exploiting the weakness of topology-based routing and instead utilize location-based routing for the networking of UGVs. It is generally assumed that location-based routing methods can fully utilize the location information gained from GPS. However, this may not be possible in tactical environments due to enemy GPS jamming and LOS(Line of Sight) limitations. To solve this problem, we propose a location-based routing scheme utilizing low control message that can calibrate the location information using GPS information as well as location of neighboring UGV, movement direct and speed information. Also utilizing topology-based routing scheme to solve incorrect location information in GPS jamming region.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.10 no.6
• /
• pp.15-23
• /
• 2011

Driving directly in front of the driver of a vehicle driving in front of the vehicle and it is commonly known is affected. Responding to the car in front of the driver and the vehicle in front, and these follow the model is known as Three-Car-Following Model. Platoon vehicles to follow behind the driver's visibility is affected by the a tinted vehicle, and Parameters of the model is estimated to be affected also. In this study, in Three-Car-Followng Model parameters were estimated. and the parameter values differ about whether and how analysis was performed by the level of Visible Light Transmission Percentage. RTK GPS receiving data through field experiment analyzed based on sensitivity of three car by Visible Light Transmission Percentage and ${\gamma}$. And With statistical verification of driving directly in front of the driver in front of the vehicle and that the moving vehicle is influenced also confirmed. Also Visible Light Transmission Percentage is lowered, the vehicle in front of the driver's behavior showed sensitive reactions. In the further need to research for influence analysis of traffic flow capacity by the level of VLT.

• International Journal of Highway Engineering
• /
• v.13 no.2
• /
• pp.175-185
• /
• 2011

Geometric information is a key element for evaluating traffic safety and road maintenance. This study developed an algorithm to identify horizontal alignment using global positioning system(GPS) and inertial navigation system(INS) data. Roll and heading information extracted from GPS/INS were utilized to classify horizontal alignment into tangent, circular curve, and transition curve. The proposed algorithm consists of two components including smoothing for eliminating outlier and a heuristic classification algorithm. A genetic algorithm(GA) was adopted to calibrate parameters associated with the algorithm. Both freeway and rural highway data were used to evaluate the performance of the proposed algorithm. Promising results, which 90.48% and 88.24% of classification accuracy were obtainable for freeway and rural highway respectively, demonstrated the technical feasibility of the algorithm for the implementation.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.5 no.4
• /
• pp.75-85
• /
• 2002

The introduction of GPS technique in transportation study make real time tracking of driving vehicle's position possible. Position information data gauged with three dimension(X, Y, Z) can be achieved with time-continuity and from more than two driving vehicles. For this field of study, in past day, there were many difficulties in collecting real time data, but now, it becomes easy thanks to this. But for the resonable result analysis, fully understanding of GPS data-accuracy must be proceeded. Because accompanied magnitude of error depends on the study's accuracy. For this reason, this study surveyed the GPS data's error and suggest calibrate technique. This study's result will be helpful for following studies using DGPS data. For this, this study takes two types study in road, and set triangulation coordinates, and compare it with GPS data. DGPS data contains less than 0.6m's error.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.10a
• /
• pp.279-282
• /
• 2000

물류시스템설계 및 개선의 일환으로 차량운송계획 문제는 매우 중요시되는 분야이다. 본 연구는 유전자 알고리즘을 이용한 통합물류 운송계획문제(Integrated Vehicle Routing Problem : IVRP)를 위한 전산화 모델의 개발로서 운송 중인 차량의 자동위치 조회시스템(Automatic Vehicle Location System : AVL)을 이용하여 차량운송의 통제기능을 높이며, 차량운송 효율을 높이는 목적으로 VRP문제와 AVL문제를 연계하는 통합운송시스템의 개념 연구이다. 본 연구에서는 다-물류센터를 고려한 운송 영역할당(Sector Clustering), 경로계획 문제(VRP) 및 유전자 알고리즘을 이용한 운송순서 계획(GA-TSP)을 고려한 통합운송계획모델의 개발을 목적으로 차량의 운송간의 통신 및 통제 등의 기능을 위하여 위치 추적을 가진 GPS와 통신시스템을 위한 TRS 및 위치설정을 위한 GIS를 고려하였다. 본 연구에서의 AVL시스템 개발을 위한 GPS, GIS 및TRS 등 AVL시스템의 구성요소에 대하여 그 개요를 조사 연구하였다. 또한 GPS, GIS을 기반으로한 물류시스템의 구성과 시스템에 필요한 기능 및 구성요소를 파악하고 서브 시스템을 구성하여 각 서브 시스템의 기본설계를 실시하기 위한 연구이다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.95-97
• /
• 2010

Recently, CAN network technology and MOST network are introduced in vehicle to control many electronic devices and to provide entertainment service. Many interconnected devices operate in MOST network which has ring topology such as CD-ROM(DVD), AMP, VIDEO CAMERA, VIDEO DISPLAY, GPS NAVIGATION and so on. In this paper, The input image of CAMERA in the MOST network is used for determining the movement direction of vehicle. Even though the position information was received from GPS, it is difficult to directly determine the direction of moving vehicle in certain areas such as the parallel road structure. This paper designs and implements the method to determine vehicle's direction by real-time matching between CAMERA image and object image base on image DB.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.11
• /
• pp.2471-2477
• /
• 2010

lately, vehicle blackbox increasing importance and usability Is needed accuracy and variety of information. because, blackbox help to analyze the exact cause of the accident and use as objective evidence in vehicle-related crime. In the paper, to overcome the limitations of the existing black box, use various sensors and vehicle information blackbox store current state of the vehicle with OBD-II protocol using vehicle state information and store exact current location and direction information of the vehicle with Gyro sensor and GPS and use global time of GPS for synchronization of information. In addition, blackbox back the information up with wifi. because, when blackbox damaged, dirvers were able to verify the information.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.05a
• /
• pp.422-424
• /
• 2010

Recently the car attached many ECUs and entertainment devices to provide the easiness maintenance and driver's convenience. CAN and MOST networks have been used to manage and control those devices in the car. Wireless network also has been established to receive information from external. These days a car navigation system with GPS is being integrated with CAN, MOST and Wireless network. In these circumstances, the car navigation system can have HMI function to integrate and control the car networks' devices. To solve the GPS problems such as positioning errors or losing signals from satellites in the tunnels and urban canyons, this paper designs and implements a method for positioning vehicle by using the sensing data of sensors and Wi-Fi devices based on this integrated environment.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.884-887
• /
• 1996

This paper describes a GPS/DR integration filter for a car navigation system. A new GPS/DR integration filter is derived for obtaining more accurate and reliable position data. The covariance analysis results and simulation results are shown for evaluating the performance of the proposed GPS/DR integration filter.