• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.843-845
• /
• 2016

Concomitant with development of AR(Augmented Reality) and VR(Virtual Reality), interest in location based games and augmented reality have increased and various services have been developed. Due to this, AR, VR, MR(Merged Reality) techniques are considered one of fourth industrial revolution techniques. Oculus Rift which is representative of VR technology, and HTC VIVE need separate controllers, and don't offer service such as receiving external video information when users are using devices. In the case of project Alloy, which is a MR device of Intel, this has advantages such as controlling devices through hand signals and facial expressions, and receiving external video information. In this paper, we propose tourist guide system based on current position using MR. This system makes economical tour possible by arranging tourist attraction information which is from current position of tourists in correct places through external video information using MR, location determination using GPS, tourism information search using wireless internet.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.20 no.3
• /
• pp.74-85
• /
• 2021

Global Navigation Satellite System (GNSS) receivers are intrinsically vulnerable to radio frequency jamming signals due to the fundamental property of radio navigation systems. A GNSS jamming monitoring system that is capable of jamming detection, classification and localization is essential for infrastructure for autonomous driving systems. For these 3 functionalities, a GNSS jamming monitoring network consisting of a multiple of low-cost GNSS receivers distributed in a certain area is needed, and the precise time synchronizaion between multiple independent GNSS receivers in the network is an essential element. This paper presents a precise time synchronization method based on the direct use of Time Difference of Arrival (TDOA) technique in signal domain. A block interpolation method is additionally incorporated into the method in order to maintain the precision of time synchronization even with the relatively low sampling rate of the received signals for computational efficiency. The feasibility of the proposed approach is verified in the numerical simualtions.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.10
• /
• pp.1290-1297
• /
• 2019

The paper proposes a distance estimation technique for ultra-wideband (UWB) systems using convolutional neural network (CNN). To estimate the distance from the transmitter and the receiver in the proposed method, 1 dimensional vector consisted of the magnitudes of the received samples is reshaped into a 2 dimensional matrix, and by using this matrix, the distance is estimated through the CNN regressor. The received signal for CNN training is generated by the UWB channel model in the IEEE 802.15.4a, and the CNN model is trained. Next, the received signal for CNN test is generated by filed experiments in indoor environments, and the distance estimation performance is verified. The proposed technique is also compared with the existing threshold based method. According to the results, the proposed CNN based technique is superior to the conventional method and specifically, the proposed method shows 0.6 m root mean square error (RMSE) at distance 10 m while the conventional technique shows much worse 1.6 m RMSE.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.10 no.2 s.21
• /
• pp.61-67
• /
• 2004

The development motive and maintenance of navigation system were military strategy purpose since middle of 20th century. During cold war period between the United States and the Soviet since the Second World War, advanced navigation system that two countries are responded individually have done development competitively. These systems are exhibited on general except military purpose gradually and are taking charge of point role in economy transport activity such as transportation of logistics between the country. Navigation system can divide into ground system and satellite system. Representative system of ground system is Loran-C(Long Range Navigation), and representative system of satellite system is GPS(Global Position System). Loran-C system is a system that use much in all the world country sea and ground, but GPS and DGPS that present is a satellite navigation system are used much. According to development of satellite system, examine about actual conditions of Loran-C navigation system and practical use plan in this paper because there is controversy about role of Loran-C navigation device along with Loran-C's operation and user decrease, and discusses for Loran-C's development direction.

• The Journal of Korea Robotics Society
• /
• v.12 no.2
• /
• pp.173-183
• /
• 2017

This paper proposes an integrated positioning system to localize a moving object in the shadow-area that exists in the water tank. The new water tank for underwater robots is constructed to evaluate the navigation performance of underwater vehicles. Several sensors are integrated in the water tank to provide the position information of the underwater vehicles. However there are some areas where the vehicle localization becomes very poor since the very limited sensors such as sonar and depth sensors are effective in underwater environment. Also there are many disturbances at sonar data. To reduce these disturbances, an extended Kalman filter has been adopted in this research. To localize the underwater vehicles under the hostile situations, a SVR (Support Vector Regression) has been systematically applied for estimating the position stochastically. To demonstrate the performance of the proposed algorithm (an extended Kalman filter + SVR analysis), a new UI (User Interface) has been developed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.241-243
• /
• 2015

Recently, There is increasing interest in the IoT(Internet of Thing) as intelligent information service that enables communication between people and things based on internet. In particular the demand for indoor location-based services with the development of smart devices is rapidly increasing. If iBeacon of BLE(Bluetooth Low Energy) is made available to provide a basic signal for the indoor location information measurement then reliability of Indoor location information for unreliable signal data for a variety of reasons, such as signal interference is significantly lowered. In this paper, Proposes a technique for obtaining an effective and reliable location information via genetic operations in order to obtain reliable location information from the iBeacon signal information.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.42 no.2
• /
• pp.424-431
• /
• 2017

These days land vehicle navigation system is a subject of great interest. The GNSS(Global Navigation Satellite System) is the most popular technology for out door positioning. However, The GNSS is incapable of providing high accuracy and reliable positioning. For that reason, we applied Network-RTK in vehicle to improve the accuracy of GNSS performance. In this network-RTK mode, the GNSS error are significantly decreased. In this paper, we explain ntrip client program for network-RTK mode and show the result of experiments in various environments.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.2
• /
• pp.425-431
• /
• 2012

In the case of outdoor moving of robot, it is differ to indoor moving case due to it cannot prepare map early for entire outdoor environments, there is nearly no research based on map because most outdoor robots use GPS. In this paper, we implement outdoor robot localization that using precision GPS and then GPS data applying MCL algorithm in outdoor environments of plane of 2 dimensional without incline section. We also perform a simple mission scenario by using applied robot localization in outdoor robot. We applying OpenRTM based on middleware, we can be controlled and grasped situation of the outdoor robot by remote through server by manager.

• Journal of Korea Multimedia Society
• /
• v.23 no.2
• /
• pp.282-292
• /
• 2020

In order to minimize casualties from marine vessel accidents that occur frequently at home and abroad, it is important to ensure the safety of the passengers aboard the vessel in the event of an accident. There is an EPIRB system as a system for disaster preparedness in the marine situation currently on the market, but there is a problem that the price is very expensive. In order to overcome the cost problem, which is a disadvantage of previous system, LoRaWAN-based communication is used. LoRaWAN communication-based vessel positioning and risk detection system based on LoRaWAN communication transmits measurement data of each module using two Beacon and GPS modules to stably perform position measurement for both indoor and outdoor situations. The rider danger situation detection system can detect the safety status of the rider using the 3-axis acceleration sensor, collect data from the rider positioning system and the rider safety status detection system, and send to server using LoRa communication. When conducting communication experiments in the long-distance maritime situation and actual communication experiments using the implemented system, it was found that the two experiments showed over 90% communication success rate on average.

• Proceedings of the Korean Information Science Society Conference
• /
• 2008.06c
• /
• pp.36-40
• /
• 2008

SIMS manages data for various spatial and non-spatial as integral management system to support space information administration environment and support several application works. Without being limited to spatial data that existent spatial Data Mining question language advances handling in this paper, did so that can find useful information from various data connected with automatically data collection, artificial satellite side upside service, remote sensing, GPS. Mobile Computing and data about Spatio-Temporal. Also, we designed spatial Data Mining query language that support a spatial Data Mining exclusive use system based on SIMS.