• Title/Summary/Keyword: Relaying signal

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Design of Open Gateway Framework for Personalized Healing Data Access (개인화된 힐링 데이터 접근을 위한 개방형 게이트웨이 프레임워크 설계)

  • Jeon, YoungJun;Im, SeokJin;Hwang, HeeJoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.229-235
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    • 2015
  • ICT healing platform is based on bio-signal and life habit information target to alarm early sickness concept prevention chronic pain. ICT(Information & Communication Technology) healing platform target on personal lead health management care of several health agencies and open of the (hospital, fitness center, health examination center, personal health device) personal health information together to personal device. Support Analysis Platform and Open API to vitalization optional services. In this paper proposal to access personality healing data Open Gateway Framework of Healing Platform Adaptor (HPAdaptor) ICT healing platform means Data relaying link to EMR(Electronic health record), korean medicine, life log, wellness, chronic pain, and fineness several personal health data provider and service provider personal healing data with software engine. After Design HPAdaptor can use for data and service provider record storage, mobile platform and analytics platform need data service or platform relying reference model.

Design and Development of A Systemic Structure to Ensure the Interoperability between the WebRTC-based Video Conferencing Systems and Heterogeneous Terminals (WebRTC 기반의 화상회의 시스템과 이기종 단말들간의 상호 연동성 확보를 위한 시스템 구조 설계 및 개발)

  • Baek, Sung Jin;Lee, Rang Hyuck;Yi, Chang Seok
    • KIISE Transactions on Computing Practices
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    • v.23 no.4
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    • pp.238-243
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    • 2017
  • This paper presents a study regarding a systemic structure that forms a link between heterogeneous terminals and the WebRTC (Web real-time communication) based video-conferencing systems. This system consists of a WebRTC-based terminal, a signal server for the relaying of the necessary signals for media negotiations, an MCU provides an interworking interface for the heterogeneous terminal, and the heterogeneous terminals that interwork with the MCU. This technology enables the interoperability between the WebRTC-based video-conferencing solutions and the legacy devices. In addition to reducing the replacement costs regarding new-technology-based solutions, the existing legacy equipment enables the use of multiparty-conference, thereby increasing the use ability of the conferencing systems.

A Preliminary Performance Analysis of the Meteorological and Ocean Data Communication Subsystem in COMS (통신해양기상위성 기상해양데이터통신계의 예비 성능 해석)

  • Kim, Jung-Pyo;Yang, Gun-Ho
    • Journal of Satellite, Information and Communications
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    • v.1 no.2
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    • pp.25-31
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    • 2006
  • The COMS (Communication, Ocean, and Meteorological Satellite) performing meteorological and ocean monitoring and providing communication service with meteorological, ocean and Ka-band payload in the geostationary orbit includes MODCS (Meteorological and Ocean Data Communication Subsystem) which provides transmitting the raw data collected by meteorological payload called MI (Meteorological Imager) and ocean payload named GOCI (Geostationary Ocean Color Imager) to the ground station and relaying the meteorological data processed on the ground to the end-user stations. MODCS comprises of two channels: SD channel which formats the raw data according to CCSDS recommendation, amplifies and transmits its signal to the ground station; MPDR channel which relays to the end-user stations the ground-processed meteorological data in the data format of LRIT/HRIT recommended by CGMS. This paper constructs the architecture of MODCS for transmitting and relating the observed data, and investigates that the key performance parameters have the required margin through the preliminary performance analyses.

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Multi-hop Packet Relay MAC Protocol Considering Channel Conditions in UWB-based WPANs (UWB 기반의 WPAN에서 채널 상태를 고려한 다중 홉 중계 방식의 MAC 프로토콜)

  • Wang Weidong;Seo Chang-Keun;Jeong Soon-Gyu;Yoo Sang-Jo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.11B
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    • pp.792-803
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    • 2005
  • Ultra wide band (UWB) technology will be applied in the high rare wireless personal area networks (WPANs) for its high rate, low power, and innate immunity to multipath fading. In this paper, a power aware multi-hop packet relay MAC protocol in UWB based WPANs is proposed and a power aware path status factor (PAPSF), which is derived from SINR and power resource condition of each device, is used to select a suitable relay node. Compared with relaying by piconet coordinator (PNC), which is easily chosen by other ad hoc routing protocol, the new scheme can achieve hi임or throughput, decrease the time required for transmitting high power signal and we can easily distribute the battery power consumption from PNC to other devices in the piconet to prevent the PNC device using up its battery too fast and finally avoid PNC handover too frequently.

Quantum Bee Colony Optimization and Non-dominated Sorting Quantum Bee Colony Optimization Based Multi-relay Selection Scheme

  • Ji, Qiang;Zhang, Shifeng;Zhao, Haoguang;Zhang, Tiankui;Cao, Jinlong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.9
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    • pp.4357-4378
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    • 2017
  • In cooperative multi-relay networks, the relay nodes which are selected are very important to the system performance. How to choose the best cooperative relay nodes is an optimization problem. In this paper, multi-relay selection schemes which consider either single objective or multi-objective are proposed based on evolutionary algorithms. Firstly, the single objective optimization problems of multi-relay selection considering signal to noise ratio (SNR) or power efficiency maximization are solved based on the quantum bee colony optimization (QBCO). Then the multi-objective optimization problems of multi-relay selection considering SNR maximization and power consumption minimization (two contradictive objectives) or SNR maximization and power efficiency maximization (also two contradictive objectives) are solved based on non-dominated sorting quantum bee colony optimization (NSQBCO), which can obtain the Pareto front solutions considering two contradictive objectives simultaneously. Simulation results show that QBCO based multi-relay selection schemes have the ability to search global optimal solution compared with other multi-relay selection schemes in literature, while NSQBCO based multi-relay selection schemes can obtain the same Pareto front solutions as exhaustive search when the number of relays is not very large. When the number of relays is very large, exhaustive search cannot be used due to complexity but NSQBCO based multi-relay selection schemes can still be used to solve the problems. All simulation results demonstrate the effectiveness of the proposed schemes.

Partial Relay Selection in Decode and Forward Cooperative Cognitive Radio Networks over Rayleigh Fading Channels

  • Zhong, Bin;Zhang, Zhongshan;Zhang, Dandan;Long, Keping;Cao, Haiyan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.3967-3983
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    • 2014
  • The performance of an partial relay selection on the decode-and-forward (DF) mode cognitive radio (CR) relay networks is studied, with some important factors, including the outage probability, the bit error ratio (BER), and the average channel capacity being analyzed. Different from the conventional relay selection schemes, the impact of spectrum sensing process as well as the spectrum utilization efficiency of primary users on the performance of DF-based CR relaying networks has been taken into consideration. In particular, the exact closed-form expressions for the figures of merit such as outage probability, BER, and average channel capacity over independent and identically distributed (i.i.d.) Rayleigh fading channels, have been derived in this paper. The validity of the proposed analysis is proven by simulation, which showed that the numerical results are consistent with the theoretical analysis in terms of the outage probability, the BER and the average channel capacity. It is also shown that the full spatial diversity order can always be obtained at the signal-to-noise ratio (SNR) range of [0dB, 15dB] in the presence of multiple potential relays.

Optimal Power Allocation for Spatial Division Multiplexing Scheme at Relays in Multiuser Distributed Beamforming Networks (다중 사용자 분산 빔포밍 네트워크의 중계기에서의 공간 분할 다중화 기법을 위한 최적 전력 할당 방법)

  • Ahn, Dong-Gun;Seo, Bang-Won;Jeong, Cheol;Kim, Hyung-Myung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.4A
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    • pp.360-370
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    • 2010
  • In this paper, a distributed beamforming problem is considered in an amplify-and-forward (AF) wireless relay network consist of multiple source-destination pairs and relaying nodes. To exploit degree of freedom of the number of beamformers, in the first step, we proposed that the sources transmit their signals through orthogonal channels. During the second step, the relays transmit their received signals multiplied by complex weights to amplify and compensate for phase changes introduced by the backward channels through one common channel. The optimal beamforming vectors are obtained through minimization of the total relay transmit power while the signal-to-interference-plus-noise ratios (SINRs) at the destinations are above certain thresholds to meet a quality of services (QoSs) level. In the numerical example, it is shown that the proposed scheme needs less transmit power for moderate network data rates than other schemes, such as space division multiplexing or time-division multiplexing scheme.

An Exact BER Analysis of Dual-Hop MIMO Decouple-and-Forward Relaying with Orthogonal Space-Time Block Codes (직교 시공간 블록 부호를 적용한 듀얼 홉 MIMO Decouple-and-Forward 릴레이에 대한 정확한 비트 에러율 분석)

  • Lee, Jae-Hoon;Kim, Dong-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.12A
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    • pp.1147-1155
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    • 2008
  • In this paper, we derive the probability density function (PDF) of end-to-end signal-to-noise ratio (SNR) for t he dual-hop MIMO (Multiple-Input Multiple-Output) DCF (Decouple-and-Forward) system. We also provide the end-to-end bit error ratio (BER) with M-ary PSK constellations for four antenna combinations. These are (1,8,1), (8,1,8), (2,4,2), and (4,2,4). Each number in the parentheses is the number of the transmit antenna at the source, the transmit and receive antenna at the relay and the receive antenna at the destination, respectively. We show t hat the end-to-end BER expression with M-ary PSK constellations makes an exact match with numerical results. We also show that MIMO DCF relay system achieves spatial diversity.

A Study on Complex Field Network Coding Scheme for Wireless Relay System (무선 릴레이 시스템에서의 Complex Field Network Coding 기법 적용에 관한 연구)

  • Hwang, Won-Jun;Jang, Jun-Hee;Choi, Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.4C
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    • pp.241-253
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    • 2011
  • In this paper, a CFNC (Complex Field Network Coding) scheme is presented, which focuses on improving transmission efficiency by reducing time slots that are needed to exchange data frames. Conventional CFNC scheme has the advantage of minimizing the number of time slots required for information exchanges. However, there exists serious performance deterioration because the transmit signals are interfered with each other. Moreover, when CFNC scheme is applied, the estimation and compensation performance of fine frequency offset severely deteriorates due to the multiple frequency offsets in received signal of relay node. In order to overcome these critical problems, we propose an improved CFNC scheme with modified maximum likelihood decision method which uses uplink transmit diversity. Also, we propose an enhanced fine frequency offset estimation method and a corresponding compensation method to deal with the multiple frequency offsets. Corresponding simulation results verify that the proposed methods are able to effectively solve the problems of CFNC scheme.

A Low Complexity Subcarrier Pairing Scheme for OFDM Based Multiple AF Relay Systems (OFDM 기반 다중 증폭 후 전달 릴레이 시스템에서 낮은 복잡도를 가지는 부반송파 페어링 기법)

  • Jeon, Eun-Sung;Yang, Jang-Hoon;Kim, Dong-Ku
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.1A
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    • pp.12-17
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    • 2009
  • We consider an OFDM based multiple AF relaying systems. Since the channel between first hop (source station-relay station) and second hop (relay station -destination station) varies independently, the subcarrier in the first hop can be paired to another subcarrier in the second hop for the increase of the system capacity. The conventional pairing which uses the brute force searching requires large complexity while giving optimal pairing for maximum system capacity. In this paper, we present sub-optimal subcarrier pairing scheme with low complexity. Every RS firstly pairs the subcarrier with the highest channel gain in the first hop to the subcarrier with highest channel gain in the second hop. The pair with the highest SNR among all the pairs is determined as final selected pair and the corresponding subcarriers are not selected at other RSs in the next paring iteration. This process is repeated until all the subcarriers are paired. Simulation results show the proposed pairing scheme achieves near optimal performance with low complexity.