• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.960-966
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• 2018

Communication antennas used at sea have been developed remarkably. However, the speed of this development is insufficient when compared with user demands. Therefore, we developed an antenna for UWB/Bluetooth that operates on 3 [GHz] and 5.72 [GHz] bands in order to use the high-speed communication network system which improved antenna miniaturization, gain and radiation patterns. To improve bandwidth, a microstrip patch antenna was selected and CST Microwave Studio 2014 program was used. Through the program, we calculated the slot width, length, transmission line width, etc. using a theoretical formula at each step. These figures were checked through simulation to see if they meet production standards. UWB for high-speed wireless communication for short-range communication at sea, Bluetooth for exchanging information at a short distance by connecting each device, and corresponding technology can be easily utilized.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.5
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• pp.13-24
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• 2005

Due to the changes in the wireless information environment, there has been an increased demand for various types of information. Accordingly, many wireless communication technologies have been studied and developed. In particular, studies on ubiquitous communications are well underway. Lately, the focus has been on the Bluetooth technology due to its applicability in various environments. Applying Bluetooth connectivity to new environments such as ubiquitous or sensor networks requires finding new wars of using it. Thus, this research analyzed the vulnerability on the limited number of slaves in a piconet configuration through the current Bluetooth communication and proposed an expanded Bluetooth piconet formation method, regardless of the number of slaves inside the piconet even if it is not configured in a scatternet. In the proposed method, we applied a security service and resolved the vulnerabilities of the current piconet by configuring an expanded form of the current tree-shaped structure.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.4
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• pp.119-125
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• 2007

In this paper, a miniaturized PCB-integrated antenna is proposed for bluetooth applications. The proposed antenna is a modified form of the printed inverted F antenna where the size reduction is achieved by employing the meander strip for the resonant length part of the radiator. The antenna dimension is optimized using the commercial electromagnetic software MWSTM. The designed antenna is fabricated by the standard photo-etching technique and its performance is measured. The fabricated antenna shows a bandwidth of 125MHz centered at 2.45GHz and a gail of -0.23dBi. The size of the proposed antenna is $9.65mm{\times}5.95mm$ corresponding to the 55 percent of the area of the existing printed inverted F antenna.

• ETRI Journal
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• v.25 no.5
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• pp.328-336
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• 2003

Bluetooth is a specification for short-range wireless communication using the 2.4 GHz ISM band. It emphasizes low complexity, low power, and low cost. This paper describes an area-efficient digital baseband module for wireless technology. For area-efficiency, we carefully consider hardware and software partitioning. We implement complex control tasks of the Bluetooth baseband layer protocols in software running on an embedded microcontroller. Hardware-efficient functions, such as low-level bitstream link control; host controller interfaces (HCIs), such as universal asynchronous receiver transmitter (UART) and universal serial bus (USB)interfaces; and audio Codec are performed by dedicated hardware blocks. Furthermore, we eliminate FIFOs for data buffering between hardware functional units. The design is done using fully synthesizable Verilog HDL to enhance the portability between process technologies so that our module can be easily integrated as an intellectual property core no system-on-a-chip (SoC) ASICs. A field programmable gate array (FPGA) prototype of this module was tested for functional verification and realtime operation of file and bitstream transfers between PCs. The module was fabricated in a $0.25-{\mu}m$ CMOS technology, the core size of which was only 2.79 $mm{\times}2.80mm$.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.160-172
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• 2018

The method of estimating a position using a GPS has been applied to various fields including a navigation system of an automobile. However, since it is difficult to measure GPS signals indoors, it is difficult to locate specific objects indoors such as a building or factory. To overcome these limitations, this study proposes a system for object location estimation based on Bluetooth5 for the management of materials in factories. The object position estimation system consists of a Bluetooth signal generator, a receiver, and a database server. A signal generator based on Bluetooth Low Energy(BLE) is attached to the material and a receiver is appropriately arranged inside the factory. In this study, we propose "Diagonal Survey Method", a 4 - axis survey algorithm using four receivers to reduce the error of existing trilateration method. The proposed algorithm showed good performance compared to the conventional trilateration and we verified the effectiveness of the proposed system and algorithm by performing the experiment by installing the system in the factory.

• Journal of Korea Multimedia Society
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• v.19 no.1
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• pp.96-103
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• 2016

Mobile electronic display applications represent a simple motion and express personal motions recently. In this context, we propose the Mobile Signage Application as against these existing applications. It provides the quality motions by multiplex editing and thus should share a kinetic typography with other people using Bluetooth. The Mobile Signage Application includes kinetic motions that are developed by HTML5 and JavaScript to attain variety effects. Furthermore, usability evaluation shows its sufficient availability and serviceability.

• International journal of advanced smart convergence
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• v.1 no.1
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• pp.1-5
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• 2012

We propose a structure for a multiple input multiple output antenna which has no space for isolation. The antenna operates in a frequency range of 2.4-2.48 GHz and can achieve a high channel capability as a Bluetooth antenna. The MIMO antenna consists of two planar inverted F antennas with symmetric structure. We designed the proposed antenna using HFSS simulator, and we designed the fabricated antenna using PCB fabricator. The MIMO antenna's isolation $S_{21}{\leq}-10dB$ and reflection coefficient $S_{11}{\leq}-20dB$. The proposed antenna's specification satisfies Bluetooth antenna's criteria and has more space than the existing MIMO antennas, which have space for isolation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.5
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• pp.1735-1754
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• 2022

The reliability and performance of WiFi need optimization because of the rising number of WiFi users day by day. A highlighted point is saving power while transmitting and receiving packets using WiFi devices. Wake-on-Wlan (WoW) is also implemented to improve energy consumption, but it also needs betterment. This paper will introduce universal ideas to transmit and receive packets using low-power technology like Bluetooth or BLE (Bluetooth low energy). While looking for power-saving ways in this research, WiFi connection and maintenance also take care using lesser power-consuming technology. Identifying different use-cases where low power technology can help save energy and maintain 802.11 connection is part of the research. In addition, the proposed method discuss energy saving with unicast and broadcast/multicast data. Calculation of power-saving and comparison with standalone WiFi usage clearly shows the effectiveness of the proposed method.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.5
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• pp.275-281
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• 2018

Along with the growing market for pets and the increasing interest in pet management, the need for pet management systems is increasing. Development of IoT-related technologies has made it possible to develop the related systems. This paper implements a variety of functions through Bluetooth 4.0 and LoRa communication between devices using Arduino and Android applications depending on distances. In the paper, users can receive real-time location information through the communication between Android applications and devices attached to pets, store pet information, manage pet information, and store stroll courses more conveniently with the developed system.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.185-193
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• 2014

In this paper, we developed a 4-channel particle counter for measuring particles, temperature, humidity in production facilities of clean-room environment, and the measured data can be transmitted via bluetooth. To measure the particle size ranging 0.3um~5um, we designed optical lens, particle detection chamber and multi-channel particle detection circuit. And we also developed a FMS program for real-time monitoring of measuring data, which resulted in the stable operation.