• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.8
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• pp.958-966
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• 2012

This paper presents a compact bluetooth/WiFi dual-mode dual-band RF front-end module(FEM) is realized by low temperature co-fired ceramic(LTCC) technology. The proposed RF front-end module consists of a diplexer, baluns in the LTCC substrate, and an SPDT switch, an SP3T switch on the LTCC substrate. In order to reduce the module size and increase integration level, the proposed diplexer and balun are designed using LC lumped elements. The parasitic elements caused by coupling effect between metal pattern layers and ground plane layer are considered during the design. The fabricated dual-mode RF front-end module has 13 pattern layers including three inner ground layers and it occupies less than $3.0mm{\times}3.7mm{\times}0.66mm$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.5
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• pp.1095-1100
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• 2013

Carbon dioxide is a major cause for which accelerates Global Warming. Therefore several countries are working on the project recommended to use a bicycle instead of the car when you move to the nearby destination in an effort to reduce the emissions of carbon dioxide. In this paper, It was developed to measure the greenhouse gas reduction using Bluetooth Sensor Node by riding a bicycle instead of a car and management system in order to authenticate the riding record. The developed application provides various information such as individual bicycle mileage, greenhouse gas reductions, bicycle riding path, the number of planted ginkgo trees. This proposed system is expected to be helpful to green house gas emission reduction because the usage rate of bicycle will increase if government combine ways to offer people rewards such as pin money or tax breaks for people who take advantage of the bicycle with the project.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3385-3390
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• 2015

In this paper, we constructed using a Cortex M3 microcontroller developed by ARM Inc. as a way to control the LED light more efficiently. And Using the short-range wireless communication by the Bluetooth communication method applied to control the LED light was configured to wirelessly control the wireless circuits. In this paper, users can easily download and easy to wirelessly control the LED lighting control circuit to design an Android application from Android-based smartphone so that you can control with your smartphone to have anyone to control the LED lighting control circuit wirelessly. If the LED lights radio control circuit is configured with the Cortex M3 in this paper is applicable to both indoor and outdoor and eco-friendly technology, is using LED driver to enhance the efficiency of the LED becomes stable voltage supply is made, the brightness of LED lighting control.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.12
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• pp.481-490
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• 2016

Bluetooth utilizes a symmetric key that is exchanged at the first pairing to establish a secure channel. There are four authentication modes which enables device authentication, Just work, Passkey Entry, Out of Band, and Numeric Comparison. Up to now, Just work has been considered as the authentication mode that is vulnerable to Man-In-The-Middle (MITM) Attack. In addition, it is possible to intentionally change any authentication mode to Just work mode, in order to succeed in MITM Attack under Just work mode. However, this kind of attacks have just worked under the assumption that users should not notice that authentication mode was changed. In this paper, We analyze the specification of Secure Simple Pairing, LE Legacy Pairing and LE Secure Connection Pairing. When using Passkey Entry mode on each approach, it seems the MITM attack is possible. Also it offers Passkey Entry MITM attack that does not require assumptions about the user's fault, because it isn't change verification process of the authentication mode unlike traditional attacks. We implement the proposed MITM attacks. Also we presents a scenario in which an attack can be exploited and a countermeasure.

• Journal of Korea Multimedia Society
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• v.6 no.2
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• pp.352-359
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• 2003

In this paper, we designed the bluetooth receiver using the microstrip bandpass filter and the high gain low noise amplifier with the 0.2$\mu\textrm{m}$ CMOS technology. A cascode inverter is adopted to implement the low noise amplifier and is one stage amplifier with a voltage reference and without the choke inductor. The designed 2.4GHz LNA was achieved a power gain of 18dB, a noise figure of 2.8dB, and the power consumption of 255mW at 2.5V power supply. Also, the microstrip receiver bandpass filter was designed that the center frequency was 2.45GHz, the bandwidth was 4% and the insert attenuation was -1.9dB. When the microstrip bandpass filter and LNA was simulated together the power gain was 16.3dB.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.9
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• pp.285-292
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• 2016

By adding short-range wireless communication function such as Bluetooth and Wi-Fi to the last vehicle in conjunction with a smart phone, a modern automobile is becoming entertainment screen to determine a variety of information such as car location information, diagnosis information, etc. through the ECU vehicle electronic control unit. In this study, by utilizing short-range communications capability of the on-board diagnostic devices and smart phones in association with the on-board diagnostics, compatibility tests among a number of smart phone models, Bluetooth and NFC(Near Field Communication) were carried out and those results were analyzed. Furthermore, composition of on-board diagnostic device having Bluetooth and NFC interface function and the fault diagnosis function were implemented, and fault diagnosis debugging program was developed. In addition, fault diagnosis data of the vehicle via the OBD-II interface was extracted. Finally, the on-board diagnostics CAN Protocol implementation has been proposed, and the results of work was analyzed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.983-993
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• 2001

This paper proposed a novel chip type ceramic dielectric antenna by using the advanced meander line technique that the radiational metals are formed on the face of ceramic dielectric(8$\times$4$\times$1.5 mm, alumina) and both faces of substrate(1.0 mm thickness, FR-4). The performance of the antenna model has a good agreements between measurements and computed results. Resultly, it has a 10 dB return-loss bandwidth(2.4∼2.4835 GHz) and 1.7 dBi measured radiation gain for Bluetooth application. The proposed antenna model can overcome the limited radiation of the small-sized antenna.

• Journal of information and communication convergence engineering
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• v.8 no.5
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• pp.586-590
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• 2010

Medical technology is gradually being developed by applying information technologies. Especially, RFID technology is being used for precise disease history information of patients [4]. And in case the patient is far away, the patient can be treated using network communication of the internet [5][6]. The internet makes us to treat or operate the patient without being restricted to time or space. If the above technologies are made as a system, the patient can be treated or operated without being restricted to time or space. In this paper, we present a patient treatment system has been implemented with a system using RFID and network communication of the internet [1][2][3][4]. The system is driven as follows. First, the information of patient can be checked from a remote PC, if the tag that a patient has been read through a reader. And a remote treatment is performed by controlling robot's arm with a joystick using internet network [19][20][21]. The RFID system was implemented in frequency of 125 KHz [1]. The information of patient can be checked with PDA, PC and C-LCD using Bluetooth and WLAN [7][8][9][10]. For the treatment and operation of the patient, the robot's arm has been formed using AX-12 motor, joystick and two buttons [11][12][13][14][15] [17][18].

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.197-200
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• 2004

In this paper, a novel triple-band planar inverted F antenna(PIFA) is proposed. The goal of this paper is to design a small antenna which is operated in triple band. Using T-shape slit and stacked U-shape parasitic patch, good impedance matching is achieved in three band. T-shape slit is inserted on the main patch in order to effectively control the excited patch surface current distributions. The proposed antenna occupies a small volume of $26{\times}9.5{\times}6mm^3$, and the obtained impedance bandwidths cover the required operating bandwidths of the GPS(1565-1585MHz), IMT-2000(1885-2200MHz) and Bluetooth (2400-2484MHz) bands.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.3
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• pp.136-143
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• 2010

Embedded systems widely used for wireless communication such as W-LAN, Bluetooth and ZigBee operate on ISM (Industrial, Scientific and Medical) band but they can be seriously affected by electromagnetic interference radiated from ISM apparatus. Therefore C.I.S.P.R. reports proposed limits for the protection of telecommunication from interference from ISM equipment. In this paper, we clarify the methods for calculating limits for disturbance signal for Embedded Systems in ISM band and propose simple way of calculating limits for interference signal in both above and below 1 GHz band cases.