• Journal of Broadcast Engineering
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• v.13 no.5
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• pp.612-621
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• 2008

Due to the various constraints such as feasible size of data payload and low transmission power, no technical specifications on the voice communication are included in the Zigbee standard. In this paper, a voice coding technique for application to the IEEE 802.15.4 standard, which is the basis of Zigbee communication, is presented. Here, both high compression and good waveform recovery are essential. To meet those requirements, a multi-stage discrete wavelet transform (DWT) block and a binary coding block consisting of two different pulse-code modulations are exploited. Theoretical analysis and simulation results in an indoor wireless channel show that the voice coder with 2-stage DWT is most appropriate from the viewpoint of compression and waveform recovery. When the line-of-sight component is dominant, the voice coding scheme has good recovery capability even in the moderate signal-to-noise power ratios. Hence, it is considered that the presented scheme will be a technical reference for the future recommendation of voice communication exploiting Zigbee.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.4
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• pp.833-839
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• 2007

In case of wireless sensor networks being applied to a target environment having continuous data transfer, high-speed data transmission and processing is necessary to meet increased bandwidth needs. This paper proposes a novel multipath routing algorithm to increase the bandwidth of continuous data stream for the wireless sensor network using dual channel routers. We evaluate performance of the proposed algorithm in the wireless sensor network using the dual channel touter based on ZigBee protocol. According to the experimental evaluation, the proposed algorithm showed outstanding performance enhancement with the bandwidth of 150kbps, which is about twice of existing single channel router.

• Journal of Digital Contents Society
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• v.7 no.2
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• pp.103-108
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• 2006

Short-range wireless communication and networking technologies are becoming increasingly important in enabling useful mobile applications. for example, ZigBee technology is expected to provide low cost and low power connectivity for equipment that needs battery life as long as several months to several years. In addition, ZigBee can be implemented in mesh networks larger than is possible with Bluetooth. The main features of this ZigBee standard are network flexibility, low cost, very low power consumption, and low data rate in an adhoc self-organizing network among fixed, portable and moving devices. Home network/Home automation is one of the key market areas for Zigbee, with an example of a simple network This paper investigates the effect of short range wireless channel on the performance of Zigbee system and DSSS-BPSK signal transmission in AWGN, interference and Rician fading environments. And we investigate performance degradation due to interference and fading effects in short range wireless channel. In particular, the impacts of the fading and interference level on the bit error probability is shown in BER performance figures.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.01a
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• pp.265-268
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• 2013

홈 네트워크 산업은 인간의 욕구와 맞물려 앞으로의 발전 가능성이 큰 분야이다. 미 가전협회의 조사에 따르면 소비자들도 홈 네트워크 시스템에 많은 관심을 가지고 있고, 애널리스트 샘 루세노는 "홈 오토메이션 시장은 해를 거듭할수록 규모가 커질 것이다."라고 예상하고 있다. 최근 네트워크 기술은 유선에서 무선으로 발전되고 있으며 홈 네트워크 서비스에는 유선보다 무선 네트워크 기술이 많이 쓰이고 있다. 본 논문에서는 각종 무선 네트워크 통신 기술에 대해 비교분석하고 홈 네트워크 서비스와의 연관성을 살펴보기 위하여 현재 홈 네트워크 서비스에 널리 사용되고 있는 무선 네트워킹 기술인 IEEE 802.11 무선랜 그룹과, IEEE 802.14.1의 블루투스 및 IEEE 802.14.5에 정의된 지그비 통신 기술에 대한 비교분석 한다.

• Journal of Korea Ship Safrty Technology Authority
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• s.27
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• pp.53-62
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• 2009

오늘날의 선박은 디지털 선박(Digital-ship)으로 변화하고 있으며, 일부 유비쿼터스(Ubiquitos) 기술을 기반으로 e-Navigation 및 VTS(Vessel Traffic Service) 등 안전 항해 및 편의를 제공하고 있다. 하지만, 아직까지 선박에 대한 안전시스템이 미비하고, 선박의 주요 설비를 실시간으로 관리하기 위한 안전 관리 시스템의 개발이 매우 필요한 시기라 할 수 있다. 지금까지 선박 연구에 있어서 안전을 극대화시키기 위한 노력은 많았으나 선박의 재질(철판) 및 밀폐환경에 의해 무선 통신(Wireless Communication)을 이용한 시스템 개발은 많이 이루어지고 있지 않은 상태이다. 본 논문은 선박 내의 전파 특성을 분석하여 무선 통신을 하기 위한 최적의 조건을 찾고, 유비쿼터스 기술을 적용한 지그비 네트워크 구성으로 선박 내 엔진관리를 위한 무선 센서 네트워크(Wireless Sensor Network)의 적용 가능성을 검증하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.571-572
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• 2013

This paper proposes a scheme of situation information gathering on zigbee system. We consider the schoolzone environment for base environment to situation information gathering, and the transmitting signal configuration and the sending method are designed and proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.5A
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• pp.457-465
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• 2010

When a sensor network is used for monitoring environments in large area or transmitting information in a u-City the number of nodes becomes very large. One of the problems with this application is the increased time delay, especially in reverse direction. In this paper, we propose a new algorithm that can minimize the latency of reverse packet in large sensor network. Analysis shows that the proposed scheme can reduce the latency by more than 90% when compared to Zigbee, while the energy consumption is maintained.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.459-461
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• 2022

In this paper, we propose a measurement system for measuring radioactivity detected in an indoor environment. This is to measure and prevent radiation generated in various spaces such as general house, workplace, and research institutes. Multi-radioactivity sensors are used to measure multiple spaces simultaneously. The measured radioactivity data is transmitted to the PC in real time through ZigBee and monitored. Even with a small amount of radioactivity, it is considered that it must be installed in a place where radiation exposure is expected, such as a laboratory or workplace, for prevention from chronic radiation syndrome.

• TTA Journal
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• s.105
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• pp.6-11
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• 2006

ITU-T SG17 국제표준화 제주회의 유치·개최/ 제6차 한·중·일 IT 표준협력회의 참가/ IT Forum Korea 2006/ IPTV, 차세대PC 신규 프로젝트그룹 본격적 활동/ OMA 표준화 총회 2007년 서울 개최 확정/ 지그비 국제공인 시험서비스 제공/ 대한민국 SW 공모대전 수상작의 GS시험 의무화 추진/ 공공SW 사업자 선정시 GS인증 가산점 기준 도입/ BQB 인정서 수여/

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.11
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• pp.895-901
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• 2013

In this paper we propose design of a multi-protocol gateway middleware based on USN. The proposed multi-protocol gateway middleware defined the transmit messages format, and were used the USN module interface protocol for connect to external application MCU using the UART. In this case, the gateway was checks the communication state of Zigbee module with settings information, and setting Zigbee serial PDU format. The experimental results of the proposed multi-protocol gateway middleware were proved the efficiency of integrate protocol gateway to use the multi-protocol gateway than gateway to using the repeater through the power control and communications a controlled experiment.