• Title/Summary/Keyword: Cellular Network

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Downlink Performance Improvement of TDD CDMA Cellular Networks with Time Slot and Fixed Hopping Station Allocations

  • Zhou, Rui;Nguyen, Hoang Nam;Sasase, Iwao
    • Journal of Communications and Networks
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    • v.9 no.3
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    • pp.247-253
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    • 2007
  • In this paper, downlink capacity of time duplex division (TDD) based cellular wireless networks utilizing fixed hopping stations is investigated. In the network, a number of fixed subscriber stations act as hopping transmission stations between base stations and far away subscribers, forming a cellular and ad hoc mobile network model. At the radio layer, TDD code division multiple access (CDMA) is selected as the radio interface due to high efficiency of frequency usage. In order to improve the system performance in terms of downlink capacity, we propose different time slot allocation schemes with the usage of fixed hopping stations, which can be selected by either random or distanced dependent schemes. Performance results obtained by computer simulation demonstrate the effectiveness of the proposed network to improve downlink system capacity.

An Enhanced Indirect Handoff for Cellular IP Network (Cellular IP 네트워크에서 인다이렉트 핸드오프 성능 개선)

  • Jung Won-soo;Yun Chan-young;Oh Young-hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.1B
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    • pp.1-8
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    • 2006
  • Currently, there are many efforts underway to provide Internet service on integrated wireless and wired networks. Supporting IP mobility is one of the major issues to construct IP based wireless network. Mobile IP has been proposed to solve the IP Mobility problem. But, in processing frequent handoffs in cellular based wireless access network, Micro mobility protocols have been proposed to solve these problems. Micro mobility protocols proposed the Cellular IP, HAWII, and Hierarchical Mobile IP. Cellular IP attracts special attention for it's seamless mobility support in limited geographical areas. New BS must be known to occur begging of handoff in Cellular IP indirect handoff. Therefore during perceiving of hanoff, packet loss or packet duplication still can occur in Cellular IP indirect handoff, which results in the degradation of UDP and TCP performance. In this paper, we propose a enhanced indirect handoff scheme for Cellular IP. Proposed handoff scheme is using a crossover node to minimize the signalling procedure and using a buffering to minimize the packet loss or packet duplication.

A new method to detect attacks on the Internet of Things (IoT) using adaptive learning based on cellular learning automata

  • Dogani, Javad;Farahmand, Mahdieh;Daryanavard, Hassan
    • ETRI Journal
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    • v.44 no.1
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    • pp.155-167
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    • 2022
  • The Internet of Things (IoT) is a new paradigm that connects physical and virtual objects from various domains such as home automation, industrial processes, human health, and monitoring. IoT sensors receive information from their environment and forward it to their neighboring nodes. However, the large amounts of exchanged data are vulnerable to attacks that reduce the network performance. Most of the previous security methods for IoT have neglected the energy consumption of IoT, thereby affecting the performance and reducing the network lifetime. This paper presents a new multistep routing protocol based on cellular learning automata. The network lifetime is improved by a performance-based adaptive reward and fine parameters. Nodes can vote on the reliability of their neighbors, achieving network reliability and a reasonable level of security. Overall, the proposed method balances the security and reliability with the energy consumption of the network.

Network-Based Protein Biomarker Discovery Platforms

  • Kim, Minhyung;Hwang, Daehee
    • Genomics & Informatics
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    • v.14 no.1
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    • pp.2-11
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    • 2016
  • The advances in mass spectrometry-based proteomics technologies have enabled the generation of global proteome data from tissue or body fluid samples collected from a broad spectrum of human diseases. Comparative proteomic analysis of global proteome data identifies and prioritizes the proteins showing altered abundances, called differentially expressed proteins (DEPs), in disease samples, compared to control samples. Protein biomarker candidates that can serve as indicators of disease states are then selected as key molecules among these proteins. Recently, it has been addressed that cellular pathways can provide better indications of disease states than individual molecules and also network analysis of the DEPs enables effective identification of cellular pathways altered in disease conditions and key molecules representing the altered cellular pathways. Accordingly, a number of network-based approaches to identify disease-related pathways and representative molecules of such pathways have been developed. In this review, we summarize analytical platforms for network-based protein biomarker discovery and key components in the platforms.

A NNAC using narrowband interference signal control in cellular mobile communication systems (셀룰라 이동 통신에서 NNAC를 이용한 협대역 간섭 신호 제어)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.3
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    • pp.542-546
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    • 2009
  • In this Paper, a back propagation neural network learning algorithm based on the complex multilayer perceptron is represented for controling and detecting interference of the received signals in cellular mobile communication system. We proposed neural network adaptive correlator which has fast convergence rate and good performance with combining back propagation neural network and the receiver of cellular. We analyzed and proved that NNAC has lower bit error probability than that of traditional RAKE receiver through results of computer simulation in the presence of the tone and narrow - band interference and the co-channel interference.

Performance Enhancement for Device-to-Device Under laying Cellular Network Using Coalition Formation Game

  • Radwan, Amr;Kim, Hoon
    • Journal of Korea Multimedia Society
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    • v.19 no.8
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    • pp.1415-1423
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    • 2016
  • Interference in device-to-device (D2D) communication underlaying cellular network needs to be elaborately investigated because of channel sharing. The objective is to improve the quality of D2D communications while maintaining high performance for cellular users. In this paper, we solve the above problem by jointly considering channel allocation and power control using coalition formation game. Our cooperative game theoric approach allows to enhance network-wide performance. We design a merge-and-split algorithm to deal with the complexity of the combinatorial structure in coalition formation problem. The analytical and numerical results show that our algorithm converges to a stable point which achieves high network performance.

CRSVP-based QoS Guaranteeing Scheme for Micro Cellular Network Environments (마이크로 셀룰러 네트워크 환경을 위한 CRSVP기반 QoS 보장 기법)

  • 정은영;박상윤;석민수;엄영익
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.6A
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    • pp.351-360
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    • 2003
  • To provide good-quality services of multimedia in wireless mobile networks, QoS for multimedia traffic should be guaranteed. However, since the existing QoS guaranteed schemes are designed for fixed networks, they are inadequate in the wireless network environments. Recently, as the size of cells like micro cell or pico cell becomes smaller. Mobile hosts on micro cellular networks, change their location frequently. It causes many drawbacks such as delayed delivery, packet losses and signaling overheads. Because the existing schemes supporting interoperability between RSVP and Mobile If are designed for macro cell environments. Their uses in micro cellular networks can be restricted. In this paper, we propose the CRSVP(Cellular RSVP Protocol) which supports QoS in micro cellular network environments.

A Device-to-device Sharing-Resource Allocation Scheme based on Adaptive Group-wise Subset Reuse in OFDMA Cellular Network (OFDMA 셀룰러 네트워크에서 적응적인 Group-wise Subset Reuse 기반 Device-to-device 공유 자원 할당 기법)

  • Kim, Ji-Eun;Kim, Nak-Myeong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.7
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    • pp.72-79
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    • 2010
  • Device-to-device(D2D) links which share resources in a cellular network present a challenge in radio resource management due to the potentially severe interference they may cause to the cellular network. In this paper, a resource allocation scheme based on subset reuse methods is proposed to minimize the interference from the D2D links. We consider an adaptive group-wise subset reuse method to enhance the efficiency of frequency resource allocation for cellular and D2D links. A power optimization scheme is also proposed for D2D links if cellular links are interfered by adjacent D2D transmissions. The computer simulation results show that performance gain is obtained in link SINR, and total cell throughput increases as nearby traffic becomes more dominant.

A COMPUTATION METHOD IN PERFORMANCE EVALUATION IN CELLULAR COMMUNICATION NETWORK UNDER THE GENERAL DISTRIBUTION MODEL

  • Kim, Kyung-Sup
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.12 no.2
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    • pp.119-131
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    • 2008
  • The paper considers the computation method in the performance evaluation of cellular network in the phase-type distribution assumptions that the channel holding times induced from mobility are modeled by well-fitted distributions to reflect an actual situation. When ww consider a phase-type distribution model instead of exponential distribution, the complexity of the computation increase exponential even though the accuracy is improved. We consider an efficient numerical algorithm to compute the performance evaluations in cellular networks such as a handoff call dropping probability, new call blocking probability, and handoff arrival rate. Numerical experiment shows that numerical analysis results are well approximated to the results of simulation.

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A Genetic Approach to Transmission Rate and Power Control for Cellular Mobile Network (ICEIC'04)

  • Lee YoungDae;Park SangBong
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.10-14
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    • 2004
  • When providing flexible data transmission for future CDMA(Code Division Multiple Access) cellular networks, problems arise in two aspects: transmission rate. This paper has proposed an approach to maximize the cellular network capacity by combining the genetic transmission rate allocation and a rapid power control algorithm. We present a genetic chromosome representation to express call drop numbers and transmission rate to control mobile's transmission power levels while handling their flexible transmission rates. We suggest a rapid power control algorithm, which is based on optimal control theory and Steffenson acceleration technique comparing with the existing algorithms. Computer simulation results showed effectiveness and efficiency of the proposed algorithm Conclusively, our proposed scheme showed high potential for increasing the cellular network capacity and it can be the fundamental basis of future research.

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