• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.2
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• pp.139-147
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• 2003

In this paper we proposed system parameter values of M-ary PPM/TH(Pulse Position Modulation/Time Hopping) ultra-wideband systems having data rate of 100 Mbps for the frequency band, which is allocated by Federal Communications Commission(FCC). We also analyzed performance of the proposed system in the AWGN channels. According to the results of performance analysis, It is observed that available pulse duration is very limitative for this system. In case of constant data rate, if M and the pulse repetition numbers are increased, then the system performance is improved and the user number is decreased.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.111-112
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• 2008

본 논문에서는 다중경로가 무수히 많은 환경에서 다중안테나를 이용하여 고속의 데이터 전송률을 달성하기 위한 초광대역(UWB: Ultra-Wideband) 시스템의 성능 향상에 대해 연구한다. 다중 수신안테나가 제공하는 공간다이버시티와 RAKE 수신기가 제공하는 시간 다이버시티가 2PAM(Binary Pulse Amplitude Modulation) TH(Time Hopping) UWB 통신 시스템의 성능에 미치는 영향을 분석한다. 시뮬레이션 결과를 통해 다중수신안테나의 수가 증가함에 따라 TH-UWB 시스템의 BER(Bit Error Rate) 성능이 크게 향상됨을 보인다. 또한 SRAKE(Selective RAKE)에 의해 선택되는 다중경로 성분의 수가 증가할수록 시스템의 성능이 더욱 향상 됨을 확인한다.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2067-2068
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• 2006

초광대역 (UWB)통신기술을 응용한 다양한 무선측위시스템은 향후, 전기-IT융합 유비쿼터스 전기설비 환경의 센서네트워크에서 중요한 역할로 대두된다. 이러한 UWB기반의 무선측위시스템은 UWB송수신기 자체의 정밀거리산출기능의 정확도 정도에 따라 그 성능이 직접적으로 좌우된다. 본 논문에서는 현재 논의되고 있는 UWB 레인징기술에 대한 소개와 특히 저비용, 저전력 운영이 가능한 단순한 구조를 갖는 비가역성(Non-coherent) UWB 레인징 시스템구조에 대해 새롭게 제안하고자 한다.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.3046-3048
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• 2005

저비용, 저전력 운영이 가능한 초광대역(UWB) 통신기술의 핵심 기술 분야 가운데 하나인 무선위치기반 시스템(Wireless Location Based System) 혹은 무선측위기술은 향후 전기-IT융합 유비쿼터스 메쉬네트워크에서 휴먼인터페이스접목, 지능형홈 뿐만아니라, 유비쿼터스 환경의 ad-hoc 센서 네트워크에서 중요한 역할을 맡게된다. 본 논문에서는 다양한 방식의 무선측위기술에 대해 소개하고자 하며, 순차송수신방식을 이용한 UWB 무선측위기반 시스템 및 운영방안을 새롭게 제안하고자 한다.

• Journal of Industrial Technology
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• v.31 no.A
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• pp.109-112
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• 2011

In this paper, we proposed a planar reversed triangle monopole antenna for UWB(Ultra Wideband) communication. RF-60A substrate of 0.64 mm thickness and 6.15 relative permitivity and 0.035 mm conductor of thickness and loss tangent 0.0025 is used for implementation. We have used Ansoft $HFSS^{TM}$(High Frequency Structure Simulator) to simulate the proposed antenna. The proposed antenna showed return losses about -10 dB, nearly omni-directional radiation patterns and maximum gains are over -5 dBi at the frequency band from 3.1 GHz to 10.6 GHz for ultra wide band communication.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.201-203
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• 2019

5G 시스템은 혁신적인 발전을 거듭하며 강력해진 기술 표준을 근간으로 초광대역 이동형 데이터 서비스, 대규모 사물통신 서비스 등을 제공하고 있다. 본 논문에서는 SW를 기반으로 한 5G의 기술 개발 방법론을 제안한다. 또, 실제 환경에서 차세대 모바일 네트워크의 성능 분석이 가능한 SW 기반의 시스템 레벨 테스트베드 및 모니터링 프로그램을 OAI(Openairinterface) 5G 연구 단체의 오픈소스를 이용하여 구현한다. 기존 하드웨어 위주의 단일 칩 시스템(SoC)을 이용한 구현은 손상되기가 쉽고 유지보수가 힘들다는 단점이 있다. 하지만 기존 하드웨어 칩을 소프트웨어 기반인 소스코드로 구현하면 유지 보수가 용이하다는 장점뿐만 아니라 하드웨어가 변경되더라도 다른 하드웨어에 호환되는 이식성 때문에 생산성이 높아지며 비용 절감의 효과도 기대할 수 있다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.1
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• pp.39-50
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• 2010

In this paper, we analyze and simulate the performance of a tactics mobile communication system based on ultra wide band (UWB) in multi-user interference (MUI) environments. This system adopts a double binary turbo code for forward error correction (FEC). Wireless channel is modeled a modified Saleh and Valenzuela (SV) model. We employ a space time block coding (STBC) scheme for enhancing system performance. System performance is evaluated in terms of bit error probability. From the simulation results, it is confirmed that the tactics mobile communication system based on UWB, which is encoded with the double binary turbo code, can achieve a remarkable coding gain with reasonable encoding and decoding complexity in multi-user interference environments. It is also known that the bit error probability performance of the tactics mobile communication system based on UWB can be substantially improved by increasing the number of iterations in the decoding process for a fixed cod rate. Besides, we can demonstrate that the double binary turbo coding scheme is very effective for increasing the number of simultaneous users for a given bit error probability requirement.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.3
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• pp.162-167
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• 2013

The variation of S11 depending on the ground sizes of circular planar monopole UWB antenna was studied. And optimal ground structure and size in UWB application devices are proposed. Radius R of circular monopole UWB antenna as a reference antenna was designed for UWB frequency band, and the measured results of this antenna on the horizontal ground plane was good agreed with the simulated results. When radius R is small, optimal size of ground plane is proposed, and when radius R is more large, minimum size of ground plane is proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.4
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• pp.359-364
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• 2013

In this paper, we propose a direct sequence ultra wideband (DS-UWB) radar system based on correlation accumulation in the fields of the ship traffic control and the safe ship operation including docking guidance systems. The proposed DS-UWB radar system averages out the noise by accumulating correlator outputs, and thus, provides a reliable distance estimation performance with a shorter estimation time compared with conventional DS-UWB radar systems. From numerical results, it is confirmed that the proposed DS-UWB radar system has not only a shorter average correlation processing time, but also a better distance estimation performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9C
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• pp.905-913
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• 2006

In the impulse radio ultra-wideband communication systems, the residual timing offset exists when the acquisition and tracking of the timing synchronization is well done. And the offset affects the performance of the system dramatically. In order to compensate the offset, we present the digital phase-locked loop that uses the reference signal in the correlation detection receiver. First, we show the degradation of BER performance that is caused by the offset, and then compensation process of the timing tracker and performance improvement. In this paper, the timing detector in the tracker operates at the sampling period of frame level uses the correlation between received and reference signal. Also, we present the performance comparison by using the computer simulation results for different Gaussian monocycle pulses.