• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.45-48
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• 2008

본 논문에서는 RF 송수신기를 이용하여 데이터를 전송하고, 전송받은 데이터를 이용하는 가운데 안전하게 통신하기 위한 방법으로 RFID 통신 프로토콜을 이용한 암호화 방법을 연구한다. 그리고 이러한 통신 프로토콜을 이용하여 안전하고 편리한 PC 보안 방법을 연구한다. 이러한 PC 보안 방법은 PC 가까이에 Tag를 소지한 사용자가 있는지 유무 판단을 하여 자동으로 PC를 보호한다. 또한 위조 변조가 불가능하며, 스니핑 공격과 스푸핑 공격에 대해 안전하다.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.519-522
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• 2010

본 논문에서는 RF 송수신기를 이용하여 데이터를 전송하고, 전송받은 데이터를 이용하는 가운데 안전하게 통신하기 위한 방법으로 RFID 통신 프로토콜을 이용한 암호화 방법을 연구한다. 그리고 이러한 통신 프로토콜을 이용하여 안전하고 편리한 PC 보안 방법을 연구한다. 이러한 PC 보안 방법은 PC 가까이에 Tag를 소지한 사용자가 있는지 유무 판단을 하여 자동으로 PC를 보호한다. 또한 위조 변조가 불가능하며, 스니핑 공격과 스푸핑 공격에 대해 안전하다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.266-271
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• 1999

The purpose in this study has to development the system on increasing operation of old-typed transceiver for solve the question that limited allocation frequencies and continuesly icreasment of traffic. Therefore, we are desigened the remote control system that has the function for variable channels, PTT and monitoring of transmission power and frequencies. Exchange of control data is to hold in common the twist two-wire or telephone line for the voice transmission. The H/W is consist of FSK and MCS-51 processor which are up-down control of channel, n control and monitoring display by serial data transmission. According to the simplex traffic operation is designed the algorithm of serial data transmission by sequential transmission sequence and protocol. The S/W of sequential transmission sequence is designed to usefully the intergrated communications system which is able to connection between the multi-transceiver and multi-terminal by master processor.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.9
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• pp.1404-1411
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• 1993

Unlike voice communication, data transmission, can be seriously affected by transient channel impairments. In some cases, timing synchronization between the transmitter and the receiver may not be recovered in the presence of these kinds of impairments without a forced reinitialization process. Therefore, it is highly desirable for data communication equipment to have an efficient timing loss detector for robust recovery. In this paper, one such detector is proposed for data transceivers haying a secondary channel embedded in the main channel. A known sequence multiplexed with the secondary channel data is repeatedly sent through the embedded secondary channel. For continuous watch-dog like operation, the detection is sequentially performed based on a modified up/down counter scheme. The performance of the proposed detector is analytically evaluated In closed form.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1C
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• pp.55-64
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• 2010

In this paper, we propose a new compensation scheme for combined channel distortions and RF impairments based on the analysis of the impacts of IQ(In-phase/Quadrature) imbalance and phase noise on the OFDM(Orthogonal Frequency Division Multiplexing) system in the direct conversion transceiver and frequency selective fading channel distortion. The proposed scheme estimates the combined distortion by the use of training symbols and the residual distortion by pilot symbols and compensates the combined distortion, including IQ imbalance, phase noise and multipath fading at the same time. The simulation results show that the proposed scheme compensates the combined distortion of IQ imbalance, phase noise and multipath fading simultaneously.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.1
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• pp.9-14
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• 2014

The path loss data was re-calculated according to the distance between the base station and a mobile station in the mobile telecommunications network. In this paper, the averaged path loss data was plotted with the conventional path loss models(free space, plane earth, Hata model ${\ldots}$). The standard deviations for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were 2.29 dB, 3.39 dB, 4.75 dB, respectively. Additionally, the derivative values for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were evaluated to find the positions with more than 1 times or 2times of the standard deviation. The situations with the sharply fluctuated path loss were calculated to 5 positions in the 2 Km interval, to 7 positions in the 1 Km interval, to 19 positions in the 0.5 Km interval, respectively. And, the exact distances between the base station and a mobile station were found with the sharply fluctuated path loss.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1165-1171
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• 2006

In this paper, we designed radio data transceiver to control the machine or equipments for automation in local areas. The designed module can transmit data with 153.6Kbps and uses 424MHz RF carrier to transmit data in the ISM band regulation. It has a processor, CPLD chip of the Altera Company, to control the data in transmitting and receiving. The processor is implemented by programming with VHDL. We will make this module with compact in dimension and higher data rate and apply to RFID technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.287-293
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• 2009

This paper would suggest about data communicate using RF Transmitter-Receiver and about PC protection method authenticate using software of PC which Receiver is connected. Older PC protection system is demanded manual operation of the user but the suggesting method protect PC automatically with judge existing of the user who has Tag approaches the distance which gets near. And it is impossible about the forgery and it is safe about sniffing attack and spoofing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.1
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• pp.70-75
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• 2014

This paper presents a IR-UWB(Impulse Radio Ultra-Wide Band) transceiver circuit for data communication and real time location system. The UWB receiver is designed to OOK(On-Off Keying) modulation for energy detection. The UWB pulse generator is designed by digital logic. And the Gaussian filter is adopted to reject side lobe in transmitter. The measured sensitivity of the receiver is -65 dBm at 4 GHz with 1 Mbps PRF(Pulse Repetition Frequency). And the measured energy efficiency per pulse is 20.6 pJ/bit. The current consumption of the receiver and transmitter including DA is 27.5 mA and 25.5 mA, respectively, at 1.8 V supply.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.997-1000
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• 2006

In this paper, we have used the 900Mha RF band and produced the transmitter-receivers to measure the distance of moving range of a crane. We selected the analog signal of 450Khz middle frequency band of the RF Baseset module, and the property data of phase response is analysed to estimate the range distance. We have earned the good results from the experiment.