• Title, Summary, Keyword: Multi-hop relay network

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Implementation of Multimedia Services in a Mobile Ad-hoc Network (이동 Ad-hoc 네트워크에서의 멀티미디어 서비스 구현)

  • Ro Kwang-Hyun;Kwon Hye-Yeon;Shin Jae-Wook;Park Ae-Soon
    • Journal of the Institute of Convergence Signal Processing
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    • v.7 no.2
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    • pp.45-52
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    • 2006
  • Mobile Ad-hoc Network(MANET) could be applied to various applications by virtue of its characteristics such as self-organizing and infrastructure-free network. This paper proposes a multimedia application service model for MANET, called multi-hop Relay(mRelay) system. It supports a multi-hop communication-based multimedia service interworked with Internet by using an unmanned moving robot with wireless multimedia communication function as a mRelay terminal. The modified AODV routing protocol was applied to the terminal and it was verified that composition and maintenance of mobile Ad-hoc network in mRelay system under the various indoor scenarios were successful and stable multi-hop multimedia services were possible. The mRelay system can be applicable to various application services of mobile Ad-hoc networks.

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Mobile-Based Relay Selection Schemes for Multi-Hop Cellular Networks

  • Zhang, Hao;Hong, Peilin;Xue, Kaiping
    • Journal of Communications and Networks
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    • v.15 no.1
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    • pp.45-53
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    • 2013
  • Multi-hop cellular networks (MCNs), which reduce the transmit power, mitigate the inter-cell interference, and improve the system performance, have been widely studied nowadays. The relay selection scheme is a key technique that achieves these advantages, and inappropriate relay selection causes frequent relay switchings, which deteriorates the overall performance. In this study, we analyze the conditions for relay switching in MCNs and obtain the expressions for the relay switching rate and relay activation time. Two mobile-based relay selection schemes are proposed on the basis of this analysis. These schemes select the relay node with the longest relay activation time and minimal relay switching rate through mobility prediction of the mobile node requiring relay and available relay nodes. We compare the system performances via simulation and analyze the impact of various parameters on the system performance. The results show that the two proposed schemes can obtain a lower relay switching rate and longer relay activation time when there is no reduction in the system throughput as compared with the existing schemes.

Outage Analysis of a Cooperative Multi-hop Wireless Network for Rayleigh Fading Environment

  • Asaduzzaman, Asaduzzaman;Kong, Hyung-Yun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.2A
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    • pp.133-138
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    • 2011
  • This paper presents an information theoretic outage analysis for physical layer of a cooperative multihop wireless network. Our analysis shows that cooperation by selecting a proper relay at each hop increases the coverage or data rate of the network. In our analysis we consider both symmetric and asymmetric network model. We also investigate the availability of cooperative relay at each hop and show that end-to-end performance of the network depends on the relay selection procedure at each hop. We also verify our analytical results with simulations.

A Study of Relay scheme for shadow area in WiBro network (와이브로 네트워크에서 음영지역에 대한 중계방식에 관한 연구)

  • Son, Sung-Chan;Oh, Chung-Gyun
    • 한국정보통신설비학회:학술대회논문집
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    • pp.394-397
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    • 2008
  • Recently WiBro network is installed for high speed wireless internet service by telecommunication service provider, however WiBro service is not provided in the region of mountain or difficult region to install network infra. Fixed repeater is used to resolve those shadow area problem in current WiBro network. This paper study introducing Ad-hoc based multi-hop relay instead of using fixed repeater in order to resolve those shadow area problem. Cost down of fixed repeater and active network expansion is possible to resolve shadow area problem by introducing multi-hop relay technology.

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A Bandwidth Adaptive Path Selection Scheme in IEEE 802.16 Relay Networks

  • Lee, Sung-Hee;Ko, Young-Bae
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.3
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    • pp.477-493
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    • 2011
  • The IEEE 802.16 mobile multi-hop relay (MMR) task group 'j' (TGj) has introduced the multi-hop relaying concept in the IEEE 802.16 Wireless MAN, wherein a relay station (RS) is employed to improve network coverage and capacity. Several RSs can be deployed between a base station and mobile stations, and configured to form a tree-like multi-hop topology. In such architecture, we consider the problem of a path selection through which the mobile station in and outside the coverage can communicate with the base station. In this paper, we propose a new path selection algorithm that ensures more efficient distribution of resources such as bandwidth among the relaying nodes for improving the overall performance of the network. Performance of our proposed scheme is compared with the path selection algorithms based on loss rate and the shortest path algorithm. Based on the simulation results using ns-2, we show our proposal significantly improves the performance on throughput, latency and bandwidth consumption.

Secure Connectivity Probability of Multi-hop Clustered Randomize-and-Forward Networks

  • Wang, Xiaowei;Su, Zhou;Wang, Guangyi
    • ETRI Journal
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    • v.39 no.5
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    • pp.729-736
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    • 2017
  • This work investigates secure cluster-aided multi-hop randomize-and-forward networks. We present a hop-by-hop multi-hop transmission scheme with relay selection, which evaluates for each cluster the relays that can securely receive the message. We propose an analytical model to derive the secure connectivity probability (SCP) of the hop-by-hop transmission scheme. For comparison, we also analyze SCPs of traditional end-to-end transmission schemes with two relay-selection policies. We perform simulations, and our analytical results verify that the proposed hop-by-hop scheme is superior to end-to-end schemes, especially with a large number of hops or high eavesdropper channel quality. Numerical results also show that the proposed hop-by-hop scheme achieves near-optimal performance in terms of the SCP.

MIMO Two-way Cooperative Relay to Improve End to End Capacity in Non-equidistant Topology

  • Niyizamwiyitira, Christine;Kang, Chul-Gyu;Oh, Chang-Heon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • pp.465-467
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    • 2010
  • This paper proposes MIMO two-way cooperative relay scheme to optimize the end to end capacity in wireless multi-hop mesh network. The basic idea is to perform data transmission via multi-hop relay nodes, in equidistant topology, this method is quite efficient. However, on one hand this topology is very rare in practical situation, on the other hand, in real practical situation where the topology is most likely non equidistant, the end to end capacity significantly degrades due to bottleneck link caused by uneven SNR. Moreover, the end to end capacity degrades at high SNR due to overreach interference from far nodes existing in multi-hop relay networks. In this paper, MIMO two-way cooperative relay in the region of non equidistant nodes is found efficient to improve the end to end capacity. The proposed scheme is validated using numerical simulation.

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Interference Cancellation for Relay-Assisted D2D Communication

  • Zhao, Hongyi;Cao, Yang;Liu, Yingzhuang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3276-3292
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    • 2015
  • Relay-assisted D2D communication extends the communication range of the D2D pairs and helps users to form D2D pairs effectively. However, due to the introduction of the multi-hop relaying, the D2D communication has to occupy extra transmission time, which may decrease the efficiency of the communication system. In this paper, we propose a scheme to make node receive D2D signal and BS signal at overlapping time to improve the spectrum efficiency according to ZigZag decoding and successive-interference-cancellation (SIC). In this way, more data can be delivered during the same duration, thus the network throughput can be further improved. Numerical results verify the performance improvement of the proposed scheme when compared with a baseline scheme. Moreover, we expand the proposed scheme from one-hop relay scenario to multi-hop relay scenario.

Spectrum Sharing-Based Multi-Hop Decode-and-Forward Relay Networks under Interference Constraints: Performance Analysis and Relay Position Optimization

  • Bao, Vo Nguyen Quoc;Thanh, Tran Thien;Nguyen, Tuan Duc;Vu, Thanh Dinh
    • Journal of Communications and Networks
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    • v.15 no.3
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    • pp.266-275
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    • 2013
  • The exact closed-form expressions for outage probability and bit error rate of spectrum sharing-based multi-hop decode-and-forward (DF) relay networks in non-identical Rayleigh fading channels are derived. We also provide the approximate closed-form expression for the system ergodic capacity. Utilizing these tractable analytical formulas, we can study the impact of key network parameters on the performance of cognitive multi-hop relay networks under interference constraints. Using a linear network model, we derive an optimum relay position scheme by numerically solving an optimization problem of balancing average signal-to-noise ratio (SNR) of each hop. The numerical results show that the optimal scheme leads to SNR performance gains of more than 1 dB. All the analytical expressions are verified by Monte-Carlo simulations confirming the advantage of multihop DF relaying networks in cognitive environments.

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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    • 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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