• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.5
• /
• pp.147-153
• /
• 2018

Beacon enables one to measure distance indoors based on low-power Bluetooth low energy (BLE) technology, while GPS (Global Positioning System) only can be used outdoors. In measuring indoor distance using Beacon, RSSI (Received Signal Strength Indication) is considered as the one of the key factors, however, it is influenced by various environmental factors so that it causes the huge gap between the estimated distance and the real. In order to handle this issue, we propose the adaptive ANN (Artificial Neural Network) based approach to measuring the exact distance using Beacon. First, we has carried out the preprocessing of the RSSI signals by applying the extended Kalman filter and the signal stabilization filter into decreasing the noise. Then, we suggest the multi-layered ANNs, each of which layer is learned by specific training data sets. The results showed an average error of 0.67m, a precision of 0.78.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.10
• /
• pp.1994-2000
• /
• 2016

Technology that can determine the location of individuals is required in a variety of applications such as location based control, a personalized advertising. Missing-child prevention and support for field trips, and applications such as push events based on the user's location is endless. In particular, the technology that can determine the location without interruption in the indoor and outdoor spaces have been studied a lot recently. Because emphasizing on accuracy of the positioning, many conventional research have constraints such as using of additional sensing devices or special mounting devices. The algorithm proposed in this paper has the purpose of performing the positioning only with standard equipment of the smart phone that has the most users. In this paper, sensor Fusion with GPS, WiFi Radio Map, Accelerometer sensor and Particle Filter algorithm is designed and implemented. Experimental results of this algorithm shows superior performance than the other compared algorithm. This could confirm the possibility of using proposed algorithm on actual environment.

• Journal of Positioning, Navigation, and Timing
• /
• v.6 no.3
• /
• pp.105-116
• /
• 2017

Several wireless localization algorithms are evaluated for the IR-UWB-based indoor location with the assumption that the ranging measurements contain the channelwise Non-Calibration Error (NCE). The localization algorithms can be divided into the Model-free Localization (MfL) methods and Model-based Kalman Filtering (MbKF). The algorithms covered in this paper include Iterative Least Squares (ILS), Direct Solution (DS), Difference of Squared Ranging Measurements (DSRM), and ILS-Common (ILS-C) methods for the MfL methods, and Extended Kalman Filter (EKF), EKF-Each Channel (EKF-EC), EKF-C, Cubature Kalman Filter (CKF), and CKF-C for the MbKF. Experimental results show that the DSRM method has better accuracy than the other MfL methods. Also, it demands smallest computation time. On the other hand, the EKF-C and CKF-C require some more computation time than the DSRM method. The accuracy of the EKF-C and CKF-C is, however, best among the 9 methods. When comparing the EKF-C and CKF-C, the CKF-C can be easily used. Finally, it is concluded that the CKF-C can be widely used because of its ease of use as well as it accuracy.

• The KIPS Transactions:PartC
• /
• v.16C no.2
• /
• pp.229-236
• /
• 2009

UWB signal with high resolution capability can be used to estimate ranging and positioning in wireless personal area networks. The clock frequency differences of nodes have serious affects on asynchronous ranging methods to estimate locations of mobile nodes. The specification of high rate UWB describes successive TWR method with the estimation of a relative clock frequency offset. In this paper, we complete the ranging equations using relative frequency offset and time information, and propose a method to estimate the exact frequency offsets. We evaluate the ranging algorithms with simulation. The results show that the performances of the algorithms using frequency offsets are very close without noise. But, at noise environment, the method of exact frequency offsets shows better performance than that of relative frequency offsets.

• Journal of Intelligence and Information Systems
• /
• v.12 no.3
• /
• pp.83-93
• /
• 2006

This paper is wireless location awareness technology using RFID. We investigates the Location of the received Signal strength reported by RF Analyses of the data are performed to understand the underlying features of location fingerprints. The system is performed factors the extreme environmental Emit signal, which consists of a unique 5000 Terminals. The Location Service have become very popular in many service industries, purchasing and distribution logistics, industry, manufacturing companies and a parking place. The Technically optimal Solution would be the storage of Intelligence information in the most common form of electronic data-carrying device in use in everyday life is the smart card based upon a contact field (telephone smart card, bank cards). The method of an indoor positioning experiment system is compared using measured Location data and a charge of service. The result of research showed the following: first, to check out the mechanism between benefit of system installation and operation of Active RFID. Second, it contributed on indoor wireless location intelligence system efficiency.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.8C
• /
• pp.605-612
• /
• 2008

This paper researches the estimating location using repeater effect adjustment method in CDMA based system. Repeaters are commonly used by commercial and amateur radio operators to extend signals in the radio frequency range from one receiver to another. The repeater signals are increasing arrival time from base station to mobile station. So if we calculates the mobile station using repeater signals, the estimating position error is increased. However nobody researched about adjusting repeater effects. This paper proposes repeater effect adjustment algorithm. For adjusting repeater effects, we make the triangle using mobile station, reference base station and neighbor base station, and then detect the repeater effects using the triangle characteristic. The proposed method system showed the improved performance in estimating parameters and locating positions by computer simulations.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.12
• /
• pp.1307-1313
• /
• 2014

In this paper, we have proposed a tapered slot antenna for IR-UWB communication system suitable of indoor positioning in the building. The designed tapered slot antenna is designed using Ansys Inc. HFSS and its standing wave ratio, return loss, and radiation pattern is analyzed. In 2.36 GHz ~ 5.51 GHz and, the designed antenna shows satisfactory return loss at -10 dB and meets the requirement of $VSWR{\leq}2$. The presented designed showed a higher sensitivity for the end-fire propagation characteristics in a specific direction across all bands of the radiation pattern.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.1
• /
• pp.129-134
• /
• 2018

Research on the technique for estimating the indoor position has been actively carried out. In particular, the WiFi fingerprint method, which does not require any additional infrastructure, is being partially used because of its high economic efficiency. The KNN method which estimates similar points to the corresponding points by comparing intensity information of the WLAN reception signal measured at various points in advance with intensity information measured at a specific point in the future is simple but has a good performance. However, in the conventional KNN scheme, since the number K of average candidate positions is constant, there is a problem that the position estimation error is not optimized according to a specific point. In this paper, we proposed an algorithm that adaptively changes the K value for each point and applied it to experimental data and evaluated its performance.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.23 no.1
• /
• pp.78-89
• /
• 1999

Clothes enhance visual images through the interaction between space and background of the wearer. The influence of background is important as that of the clothes when the observer understands the images. We look at fashion pictures used as important as that various backgrounds are presented depending on the image of the clothes. The clothing the model wears in the pictures takes on shape and space which supports the clothes. The background interact to from the whole image. The background has an important influence on the delivery of image for the clothes. However when the clothes are presented in the background there are some cases that all or parts of clothes can be shown. We must consider the composition ratio of the clothes and background which influences the whole image of the clothing. These interactions and influences on the whole image in regards to clothing background and the ratio will be the focus of this study. clothing was Modern Mannish Casual, Feminine, Ground was decided artificial setting 1 natural setting 1, indoor setting 1, artificial setting 2, natural setting 2, indoor setting 2, Percentage of Clothing was 80% , 140%, 200%,. Thus visual stimulus were 72 pictures that were combined Clothing Ground and Percentage of Clothing, the main survey of questionary consisted of their evaluation of the Picture image combined Clothing and Ground by 30 semantic differential bi-polar scales and the subjects were 50 students majoring in clothing and textile. The data analyzed by factor analysis MCA, MDS, The major finding were as follows : 1) As a result of factor analysis, 5 factors -Attractiveness Hardness and softness Cuteness Attention Cool and Warm factor were found out as constructing factors the Picture image combined Clothing and Ground 2) According to multidimensional positioning map were presented in a stimulus position the perceptive image differed in degree of similarity as a ground construction of stimulus in spite of same clothing image. It will aid in choosing the most beneficial background for any clothing brand. It will enhance the picture images to their full potential in any advertising medium.

• Journal of Digital Convergence
• /
• v.17 no.12
• /
• pp.211-217
• /
• 2019

Location positioning systems are available in applications such as mobile, robotic tracking systems and Wireless location-based service (LBS) applications. The GPS system is the most well-known location tracking system, but it is not easy to use indoors. The method of radio frequency identification (RFID) location tracking was studied in terms of cost-effectiveness for indoor location tracking systems. Most RFID systems use active RFID tags using expendable batteries, but in this paper, an inexpensive indoor location tracking system using passive RFID tags has been developed. A pattern matching method and a system for tracing location by generating regression curves were studied to use precision tracking algorithms. The system was tested by verifying the level of error caused by noise. The three-dimensional curves are produced by the regression equation estimated the statistically meaningful coordinates by the differential equation. The proposed system could also be applied to mobile robot systems, AGVs and mobile phone LBSs.