• Title/Summary/Keyword: WiFi AP

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Smart Phone Sensor-Based Indoor Location Tracking System for Improving the Location Error of the Radio Environment (무선 환경의 위치 정보 오차 개선을 위한 스마트폰 센서 기반 실내 위치 추적 시스템)

  • Lee, Dae-Young;Kang, Young-Heung
    • Journal of Advanced Navigation Technology
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    • v.19 no.1
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    • pp.74-79
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    • 2015
  • In this paper, in order to improve the error is utilized to location tracking the smart sensor detects a walking information user, RSSI is to provide an indoor position tracking system that is capable of correcting an error in terms weak. The acceleration sensor is able to detect the activity in the user walking and detects the number of step and the moving distance using the same. The Direction sensor is utilized as a digital compass, to detect the moving direction of the user. As a result of detecting the walking information using the sensor, it can be showed that this proposed indoor positioning system has a high degree of accuracy for the number of steps and the movement direction. Therefore, this paper shows that the proposed technique can correct the error of the location information to be problem in the conventional indoor location system which uses the only Wi-Fi APs by estimating the user's movement direction and distance using the sensors in smartphone without an additional equipment and cost.

Wireless LAN-based Vehicle Location Estimation in GPS Shading Environment (GPS 음영 환경에서 무선랜 기반 차량 위치 추정 연구)

  • Lee, Donghun;Min, Kyungin;Kim, Jungha
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.1
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    • pp.94-106
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    • 2020
  • Recently, the radio navigation method utilizing the GPS(Global Positioning System) satellite information is widely used as the method to measure the position of objects. As GPS applications become wider and fields based on various positioning information emerge, new methods for achieving higher accuracy are required. In the case of autonomous vehicles, the INS(Inertial Navigation System) using the IMU(Inertial Measurement Unit), and the DR(Dead Reckoning) algorithm using the in-vehicle sensor, are used for the purpose of preventing degradation of accuracy of the GPS and to measure the position in the shadow area. However, these positioning methods have many elements of problems due not only to the existence of various shaded areas such as building areas that are continually enlarged, tunnels, underground parking lots and but also to the limitations of accumulation-based location estimation methods that increase in error over time. In this paper, an efficient positioning method in a large underground parking space using Fingerprint method is proposed by placing the AP(Access Points) and directional antennas in the form of four anchors using WLAN, a popular means of wireless communication, for positioning the vehicle in the GPS shadow area. The proposed method is proved to be able to produce unchanged positioning results even in an environment where parked vehicles are moved as time passes.