• Title/Summary/Keyword: Relay Model

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Inter-clustering Cooperative Relay Selection Schemes for 5G Device-to-device Communication Networks

  • Nasaruddin, Nasaruddin;Yunida, Yunida;Adriman, Ramzi
    • Journal of information and communication convergence engineering
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    • v.20 no.3
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    • pp.143-152
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    • 2022
  • The ongoing adoption of 5G will increase the data traffic, throughput, multimedia services, and power consumption for future wireless applications and services, including sensor and mobile networks. Multipath fading on wireless channels also reduces the system performance and increases energy consumption. To address these issues, device-to-device (D2D) and cooperative communications have been proposed. In this study, we propose two inter-clustering models using the relay selection method to improve system performance and increase energy efficiency in cooperative D2D networks. We develop two inter-clustering models and present their respective algorithms. Subsequently, we run a computer simulation to evaluate each model's outage probability (OP) performance, throughput, and energy efficiency. The simulation results show that inter-clustering model II has the lowest OP, highest throughput, and highest energy efficiency compared with inter-clustering model I and the conventional inter-clustering-based multirelay method. These results demonstrate that inter-clustering model II is well-suited for use in 5G overlay D2D and cellular communications.

Outage Probability of Device-to-Device MIMO Relay Systems with Imperfect Channel Estimation

  • Wei, Liang wu;Shao, Shi Xiang
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.2
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    • pp.67-76
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    • 2013
  • Under an imperfect channel estimation, a Device-to-Device (D2D) communication framework based on MIMO relay technology is presented. The model consists of a D2D pair equipped with M antennas and a relay equipped with N antennas as well as a cellular user equipped with M antennas. The outage probability under different relaying protocols (i.e. AF and DF protocol) with and without considering a direct link was derived. The actual and theoretical outage probability of the five links under different antenna numbers was emulated. The number of user antennas and channel estimation error was analyzed carefully to determine their impact on the outage probability of a system. The simulation verified the theory analyses and the results showed that MIMO relaying improves the D2D communication system performance.

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The Implementation of Operation for Underfrequency Relay using EMTP MODELS (EMTP MODELS를 이용한 부족주파수 계전기 동작 구현)

  • Ahn S.P.;Heo J.Y.;Kim C.H.;Park N.O.
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.575-577
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    • 2004
  • This paper propose methods to implement operation of underfrequency relay using EMTP MODELS. Simulation results shows the operation of the frequency relay as well as the status of generator and power systems. The simulation method described in this paper can thus be employed as a very useful tool in the testing of frequency relay algorithms and/or in the development of any new ones.

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Security performance analysis of SIMO relay systems over Composite Fading Channels

  • Sun, Jiangfeng;Bie, Hongxia;Li, Xingwang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.6
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    • pp.2649-2669
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    • 2020
  • In this paper, we analyze the secrecy performance of single-input multiple-output (SIMO) relay systems over κ-μ shadowed fading channels. Based on considering relay model employing decode-and-forward (DF) protocol, two security evaluation metrics, namely, secure outage probability (SOP) and probability of strictly positive secrecy capacity (SPSC) are studied, for which closed-form analytical expressions are derived. In addition, Monte Carlo results prove the validity of the theoretical derivation. The simulation results confirm that the factors that enhance the security include large ratio of (μD, μE), (mD, mE), (LD, LE) and small ratio of (kD, kE) under the high signal-to-noise ratio regime.

A Cooperative Transmission Strategy using Entropy-based Relay Selection in Mobile Ad-hoc Wireless Sensor Networks with Rayleigh Fading Environments

  • An, Beong-Ku;Duy, Tran Trung;Kong, Hyung-Yun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.3 no.2
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    • pp.147-162
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    • 2009
  • In this paper, we propose a Cooperative Transmission Strategy using Entropy-based Relay Selection in Mobile Ad-hoc Wireless Sensor Networks(MAWSN) with Rayleigh Fading Environments. The main features and contributions of the proposed cooperative transmission strategy are as follows. First, entropy-based relay selection is used to improve data transmission reliability from a source node to a destination node. Second, we present a theoretical analysis model for the proposed cooperative transmission strategy with the outage probability of the end-to-end performance. The performance of our protocol is evaluated using analysis and simulation.

A Study on Simulator for Testing of Digital Protective Relay (디지털 보호계전기의 시험을 위한 시뮬레이터에 관한 연구)

  • Park, Chul-Won;Shin, Myong-Chul;Ahn, Tae-Pung
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.55 no.4
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    • pp.183-189
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    • 2006
  • In this work, the digital simulator for testing of digital protective relay is presented. The proposed simulator software has EMTP simulation data file conversion, sequence waveform generation, user define simulation data generation, communication engine, data analysis engine and measurements function etc. The simulator hardware is designed using 32bit floating point DSP architecture to achieve flexibility and high speed operation. This simulator is tested to evaluate the performance of relay simulator by using a output data of simulation model on EMTP.

A Cognitive Radio based Multi-hop Relay Cellular Network

  • Hassan, Md. Imrul;Song, Ju-Bin;Kim, Young-Il
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.97-98
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    • 2007
  • In this paper, we investigate the throughput capacity of a multi-hop relay network with cognitive radio (CR) enabled relay stations (RS). We suggested a TDMA/FDMA based frame structure where RSs dynamically select unused channels to communicate with the base station (BS) using CR techniques to analyze the throughput capacity. We developed the throughput capacity model for the proposed system based on utilization factor. The analytical results based on those equations show significant improvement in throughput capacity for CR enabled multi-hop relay system.

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A Study on Evaluation of Optimal Replacement Period by Reliability Prediction for the Door Control Relay of EMU (전동차 출입문제어 계전기의 신뢰도예측을 통한 적정 교체주기 연구)

  • Han, Jaehyun;Kim, JongWoon;Koo, JeongSeo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.7
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    • pp.34-40
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    • 2014
  • In this paper, we want to know the optimal replacement cycle(time) for this study was performed. The optimal preventive replacement age can be fond by finding the value of time that minimizes the cost function(model of Barlow and Jardine). In addition, The reliability of the relay according to the service environment were studied. The use of the exchange relay period is longer, and maintenance cost rate(per hour) may increase, and also the reliability may cause a decline. In addition, considering the preventive maintenance and purchase order, a representative relay(RAX-L440-A type) life was calculated.

Towards reducing acoustical high-frequency noise of a direct current relay via contact structure (직류 계전기의 접촉구조에 의한 고주파수 소음저감)

  • Junhyeok, Yang;Jongseob, Won;Wonjin, Kim
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.6
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    • pp.691-697
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    • 2022
  • In this work, a straightforward component design of a direct current (DC) relay equipped in electric vehicles is discussed. The work aims to provide and evaluate effective measures for reducing high-frequency sound from the DC relay carrying electric power. From the operation experiments for the relay, it is observed that noise is caused by the resonance from the forced vibration by the electromagnetic repulsive force originating at the area of electric contacts with a resonance frequency of around 710 Hz ~ 730 Hz. A finite element model for the relay was established to conduct vibration mode analysis, consisting of stationary and movable contacts and a contact spring. Vibration mode analysis indicates that in the resonance frequency, the movable contact with two-point contacts experiences rotational vibration mode. For the proposed relay with a three-point contact, vibration mode analyses give reasonable results of reducing noise at that frequency. Furthermore, for the fabricated relays with the three-point contact, similar results have been obtained. In conclusion, one can see that the proposed measures provide one of the feasible solutions to the reduction of relay noise.

Development of Education and Training System for the Auto-Reclosing of Power Transmission System Using a Real Time Digital Simulator (실시간 계통시뮬레이터를 이용한 송전계통 자동재폐로 교육 및 훈련 시스템 개발)

  • Park, Jong-Chan;Yun, Sang-Yun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.1
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    • pp.1-9
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    • 2010
  • This paper summarizes an education and training system for the auto-reclosing of power transmission system using a real time digital simulator. The system is developed to understand the principle of reclosing and the sequence of automatic reclosing schemes, and practice the effects of reclosing actions to power system in real-time simulator. This study is concentrated into the following two parts. One is the development of real time education and training system of automatic reclosing schemes. For this, we use the RTDS(real time digital simulator) and the actual digital protective relay. The mathematical relay model of RTDS and the actual distance relay which is equipped automatic reclosing function are also used. The other is the user friendly interface between trainee and trainer. The various interface displays are used for user handing and result display. The conditions of automatic reclosing which is a number of reclosing, reclosing dead time, reset time, and so on, can be changed by the user interface panel. A number of scenario cases are reserved for the education and training. Through the test, we verified that the proposed system can be effectively used to accomplish the education and training of automatic reclosing.