• Title/Summary/Keyword: multi-hop communications

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Multi-Hop Cooperative Transmission Using Fountain Codes over Rayleigh Fading Channels

  • Duy, Tran Trung;Anpalagan, Alagan;Kong, Hyung-Yun
    • Journal of Communications and Networks
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    • v.14 no.3
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    • pp.267-272
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    • 2012
  • In this paper, we study multi-hop cooperative transmission protocols using fountain codes. The proposed protocols can reduce the end-to-end delay and number of stages compared to those in conventional multi-hop transmission. VariousMonte-Carlo simulations are presented to evaluate and compare performance of the protocols over Rayeigh fading channels.

NETWORK-ADAPTIVE ERROR CONTROL FOR VIDEO STREAMING OVER WIRELESS MULTI-HOP NETWORKS

  • Bae, Jung-Tae;Kim, Jong-Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.385-389
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    • 2009
  • Multi-hop wireless mesh networks (WMNs) suffer from significant packet losses due to insufficient available bandwidth and high channel error probability. To conquer packet losses, end-to-end (E2E) error control schemes have been proposed. However, in WMNs, E2E error control schemes are not effective in adapting to the time-varying network condition due to large delay. Thus, in this paper, we propose a network-adaptive error control for video streaming over WMNs that flexibly operates E2E and hop-by-hop (HbH) error control according to network condition. Moreover, to provide lightweight support at intermediate nodes for HbH error control, we use path-partition-based adaptation. To verify the proposed scheme, we implement it and evaluate its transport performance through MPEG-2 video streaming over a real IEEE 802.11a-based WMN testbed.

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An Energy-Efficient Multicast Algorithm with Maximum Network Throughput in Multi-hop Wireless Networks

  • Jiang, Dingde;Xu, Zhengzheng;Li, Wenpan;Yao, Chunping;Lv, Zhihan;Li, Tao
    • Journal of Communications and Networks
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    • v.18 no.5
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    • pp.713-724
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    • 2016
  • Energy consumption has become a main problem of sustainable development in communication networks and how to communicate with high energy efficiency is a significant topic that researchers and network operators commonly concern. In this paper, an energy-efficient multicast algorithm in multi-hop wireless networks is proposed aiming at new generation wireless communications. Traditional multi-hop wireless network design only considers either network efficiency or minimum energy consumption of networks, but rarely the maximum energy efficiency of networks. Different from previous methods, the paper targets maximizing energy efficiency of networks. In order to get optimal energy efficiency to build network multicast, our proposed method tries to maximize network throughput and minimize networks' energy consumption by exploiting network coding and sleeping scheme. Simulation results show that the proposed algorithm has better energy efficiency and performance improvements compared with existing methods.

A Multi-hop OFDM Frame Structure for Short-Range Underwater Acoustic Communication Networks

  • Yu, HaiFeng;Kim, Woon;Chang, KyungHi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.5
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    • pp.809-811
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    • 2015
  • In this paper, for the purpose of providing high data rate services, the multi-hop frame structure is designed for the underwater acoustic (UWA) short-range system which is proposed as a part of ocean surveillance and tracking network (OSTN). Under the measured underwater channel environment, the link-level system performance are also evaluated. Simulation results show not only the packet error rate (PER) comparisons, but the optimal modulation and coding scheme (MCS) levels for the orthogonal frequency division multiplexing (OFDM) based short-range UWA communications network.

Enhanced CSMA/CA Protocol for multi-hop wireless Ad-hoc networks (멀티 홉 무선 Ad-hoc 네트워크를 위한 개선된 CSMA/CA 프로토콜)

  • 김남일;황유선;김응배
    • Proceedings of the IEEK Conference
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    • 2003.11c
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    • pp.231-234
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    • 2003
  • In this paper, we propose the enhanced CSMA/CA MAC protocol fir mobile multi-hop wireless Ad-hoc networks. In the conventional wireless Ad-hoc network such as WLAN using CSMA/CA MAC protocol, communications between terminals that fn connected within multi-hop node may degrade the transmission efficiencies as increasing the multi-hop nodes because of RTS-CTS-DATA-ACK message exchange between terminals. In this raper, we apply the ACK/RTS control message into multi-hop transmission between terminals for wireless ad-hoc networks and improve the data traffic transmission efficiencies compared with conventional CSMA/CA MAC protocol used in WLAN.

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Wireless Multihop Communications for Frontier cell based Multi-Robot Path Finding with Relay Robot Random Stopping (다중홉 통신 기법을 활용한 네트워크 로봇의 협력적 경로 탐색)

  • Jung, Jin-Hong;Kim, Seong-Lyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.11B
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    • pp.1030-1037
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    • 2008
  • This paper presents an algorithm for the path-finding problem in unknown environments with cooperative and commutative multi-robots. To verify the algorithm, we investigate the problem of escaping through the exit of a randomly generated maze by muti-robots. For the purpose, we adopt the so called frontier cells and cell utility functions, which were used in the exploration problem for the multi-robots. For the wireless communications among the mobile robots, we modify and utilize the so called the random basket routing, a kind of hop-by-hop opportunistic routing. A mobile robot, once it finds the exit, will choose its next action, either escape immediately or stay-and-relay the exit information for the others, where the robot takes one action based on a given probability. We investigate the optimal probability that minimizes the average escaping time (out of the maze to the exit) of a mobile robot.

Performance Analysis of Multi-hop Wireless Networks under Different Hopping Strategies with Spatial Diversity

  • Han, Hu;Zhu, Hongbo;Zhu, Qi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.10
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    • pp.2548-2566
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    • 2012
  • This paper derives two main end-to-end performance metrics, namely the spatial capacity density and the average end-to-end delay of the multi-hop wireless ad hoc networks with multi-antenna communications. Based on the closed-form expressions of these performance metrics, three hopping strategies, i.e., the closest neighbor, the furthest neighbor and the randomly selected neighbor hopping strategies have been investigated. This formulation provides insights into the relations among node density, diversity gains, number of hops and some other network design parameters which jointly determine network performances, and a method of choosing the best hopping strategy which can be formulated from a network design perspective.

A Novel Social Aware Reverse Relay Selection Scheme for Underlaying Multi- Hop D2D Communications

  • Liang Li;Xinjie Yang;Yuanjie Zheng;Jiazhi Yang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.10
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    • pp.2732-2749
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    • 2023
  • Device-to-Device (D2D) communication has received increasing attention and been studied extensively thanks to its advantages in improving spectral efficiency and energy efficiency of cellular networks. This paper proposes a novel relay selection algorithm for multi-hop full-duplex D2D communications underlaying cellular networks. By selecting the relay of each hop in a reverse manner, the proposed algorithm reduces the heavy signaling overhead that traditional relay selection algorithms introduce. In addition, the social domain information of mobile terminals is taken into consideration and its influence on the performance of D2D communications studied, which is found significant enough not to be overlooked. Moreover, simulations show that the proposed algorithm, in absence of social relationship information, improves data throughput by around 70% and 7% and energy efficiency by 64% and 6%, compared with two benchmark algorithms, when D2D distance is 260 meters. In a more practical implementation considering social relationship information, although the proposed algorithm naturally achieves less throughput, it substantially increases the energy efficiency than the benchmarks.

An Effective Multi-hop Relay Algorithm in Wireless Mesh Network (무선 메쉬 네트워크 환경에서 효율적인 다중 홉 전달 기법)

  • Kim, Young-An;Park, Chul-Hyun;Hong, Choong-Seon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10B
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    • pp.872-882
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    • 2006
  • The Wireless Mesh Network uses a wireless communication technology with transmission rates similar to that of a cable, which is used as a backbone network. The topology structure is in a Mesh form which resembles an Ad-hoc network, however a metric is needed in order to set the channel and channel methods since the operation intentions and interior motions are different. This thesis proposes a metric(ETR : Expected Transmission Rate) that sets the channel with physical link performance and multi hop transmission capabilities. This metric will also be based on multi channel creation methods and Hop-by-hop routing techniques for an effective multi hop transmission with no loops.