• Title/Summary/Keyword: IEEE 802.16/WiBro system

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An Adjustment Algorithm for Bandwidth Grant Interval of UGS Class in IEEE 802.16/WiBro Systems (IEEE 802.16/WiBro 시스템에서의 UGS 클래스 대역폭 할당 주기 조정 알고리즘)

  • Baek, Joo-Young;Yoon, Jong-Pil;Lee, Jeong-Yoon;Suh, Young-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.5
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    • pp.370-374
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    • 2009
  • In this paper we propose an adjustment algorithm for bandwidth grant interval of UGS class flows the overload status of certain frames occurs due to the pre-defined grant interval mechanism of UGS class. In IEEE 802.16/WiBro systems, UGS class is the highest priority to guaranteed QoS Parameters. However, existing grant interval mechanisms of UGS class do not consider the condition that the grant interval of multiple UGS class flows overlaps with certain frames, and thus it causes the overload status in the system. Therefore, the system cannot be guaranteed QoS for UGS class flows. In this paper, we show the occurrence of the problem through simulation studies and propose an adjustment algorithm to solve the problem. Our simulation results show that there is performance improvement in the proposed algorithm. We expect that the real system in which the proposed scheme is applied can provide more stable QoS services by reducing the delay problem that occurs due to the occurrence of the existing grant interval problem of UGS class.

Two Stage Dropping Scheme Considering Latency of rtPS Class in IEEE 802.16/WiBro System (IEEE 802.16/WiBro 시스템에서의 rtPS 클래스의 지연을 고려한 두 단계 드롭 기법)

  • Baek, Joo-Young;Yoon, Jong-Pil;Kim, Sok-Hyong;Suh, Young-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.8
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    • pp.783-787
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    • 2008
  • IEEE 802.16/WiBro, one of the representative Broadband Wireless Access (BWA) systems, defines QoS negotiation between BS and SS and five service classes to guarantee QoS for flows. The five service classes are UGS, ertPS, rtPS, nrtPS, and BE, but the standard does not define how to provide services to flows according to the service classes. Existing research works have been studied about the scheduler architecture to effectively utilize the IEEE 802.16/WiBro systems. These works use the original packet scheduling algorithm for service classes. However, it is necessary to consider bandwidth allocation mechanisms in scheduling algorithms since bandwidth allocation mechanisms are different according to service classes. Especially, bandwidth allocation mechanisms should be considered for the scheduling of rtPS class since rtPS class uses the polling mechanism that takes time to allocate bandwidth and has the minimum latency constraint. Therefore, we propose two stage dropping scheme for rtPS class that is sensitive to latency, and thus it reduces the wasted resources and provides efficient service to rtPS class.

Analysis of Termination Capacity in IEEE 802.16 Broadband Wireless Access Environments (IEEE 802.16 BWA 환경에서의 가입자 수용용량 분석)

  • Lim Seog-Ku
    • The Journal of the Korea Contents Association
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    • v.5 no.6
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    • pp.65-73
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    • 2005
  • Request about fast diffusion of internet and high-capacity multimedia service is increasing day after day. Because existent wireless LAN is short range, if subscriber is far away in base station transceiver system(Base Station), subscriber's quality of service becomes low, and wileless internet is expensive. Lately, WiBro(Wireless Broadband Internet) system that is developed in domestic by world first, is high-speed portable internet service that is situated in middle area of mobile phone and wireless LAN. In this paper, service traffic model and characteristics are analyzed to provide multimedia service based on IEEE 802.16 BWA accomplishes base of WiBro and simulation is conducted according to various traffic mixing ratio. Finally, on the basis of these simulation results, maximum allowable number of subscriber per cell is calculated.

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Performance Improvements of WiBro System Using the LVQ Blind Equalization (LVQ 자력등화를 이용한 와이브로 시스템의 성능 개선)

  • Park, Jin-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.10
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    • pp.2247-2253
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    • 2010
  • WiBro(Wireless Broadband Internet) is the standard of high-speed portable internet based on OFDMA/TDD (Orthogonal frequency division multiple access / Time division duplexing) techniques, and the subset of consolidated version of IEEE802.16e Wireless MAN standard. In this paper, we propose performance improvements of WiBro system using the LVQ(Learning Vector Quantization) blind equalization. Proposed method used the prefiltering LVQ neural network blind equalization in the Broadband WiBro system receiver. The prefiltering LVQ neural network constellates 16QAM that is transmitter data shape and the blind equalization removes ICI(Inter Carrier Interference). To verificate the proposed method usability, the MSE(Mean Square Error) and the BER(Bit Error Rate) are simulated. The simulation results shown that is improved the performances of the proposed WiBro system using the LVQ blind equalization than the existing WiBro system.

The Design Method of WiBro System Using the SOFM Blind Equalization (SOFM 자력등화를 이용한 와이브로 시스템 설계 방법)

  • Park, Jin-Woo;Eom, Ki-Hwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.9
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    • pp.1638-1645
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    • 2008
  • WiBro(Wireless Broadband Internet) is the standard of high-speed portable internet based on OFDMA/TDD techniques, and the subset of consolidated version of IEEE802.16e Wireless MAN standard. In this paper, we propose the design method of WiBro system using the SOFM Blind Equalization. Proposed design method used SOFM neural network blind equalization with Bussgang algorithms in the Broadband 16 QAM WiBro system receiver. To verificate the proposed design method usability, the MSE and the BER are simulated. The simulation results shown that is improved the equalization performances of the proposed WiBro system using the SOFM Blind equalization than the existing WiBro system.

Design and Analysis of Transmission Parameters for DH(Dog-Horse) Systems Based on IEEE802.16e (WiBro) (견마로봇 시스템의 상향링크 고속신호 전송을 위한 시스템 WiBro(IEEE802.16e) 통신변수 설계 및 분석)

  • Lee, Il-Shin;Yoo, Jae-Ho;Lee, Yoon-Ju;Kwon, Dong-Seung;Chung, Jae-Hak
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.45 no.6
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    • pp.1-9
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    • 2008
  • This paper presents transmission parameters of DH(Dog-Horse) systems based on IEEE802.16e(WiBro) systems. DH requires higher uplink multimedia data rate, which is different from commercial WiBro systems. This paper designes some transmission parameters satisfying the DH system requirements and demonstrates link performance evaluation based on the parameters. For the transmission parameters, the number dwon/up link OFDM symbols are determined by 6/30, respectively. For reliable transmission of control signals, downlink modulation and coding rate are selected by QPSK, 1/2 coding rate and that of uplink is chosen by 16QAM 1/2 and 3/4 coding rate. Based on these parameters, computer simulations demonstrate the system performance of DH system.

Performance Improvements of WiBro System Using the 64QAM SOFM Prefiltering (64QAM SOFM 전처리기를 이용한 와이브로 시스템의 성능 개선)

  • Park, Jin-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.5
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    • pp.1125-1132
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    • 2010
  • WiBro(Wireless Broadband Internet) is the standard of high-speed portable internet based on OFDMA/TDD (Orthogonal frequency division multiple access / Time division duplexing) techniques, and the subset of consolidated version of IEEE802.16e Wireless MAN standard. In this paper, we propose performance improvements of WiBro system using the 64QAM SOFM(Self-Organizing Feature Maps)prefiltering. Proposed method used the prefiltering SOFM neural network blind equalization in the Broadband 64 QAM WiBro system receiver. The prefiltering SOFM neural network constellates 64QAM that is transmitter data shape and the blind equalization removes ICI(Inter Carrier Interference). To verificate the proposed method usability, the MSE and the BER are simulated. The simulation results shown that is improved the performances of the proposed WiBro system using the 64QAM SOFM Prefiltering than the existing WiBro system.

Specification-based Intrusion Detection System for the Initial Authentication Phase of WiBro (와이브로의 초기인증에 적합한 명세기반의 침입탐지시스템)

  • Lee, Yun-Ho;Lee, Soo-Jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.20 no.2
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    • pp.23-32
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    • 2010
  • WiBro(Wireless Broadband), the service based on IEEE 802.16e(mobile WiMAX) standard, is a wireless broadband Internet technology being developed by the domestic telecommunication industry. In this paper, we analyze security vulnerabilities of WiBro focusing on initial authentication phase and propose a specification-based intrusion detection system that can detect those vulnerabilities. We first derive a specification from the normally operational process of the initial authentication based on PKMv2 EAP-AKA and formalize the derived specification as a state transition diagram. Proposed system executes the intrusion detection based on those specification and state transition diagram. In this paper, to verify the detection capability of proposed system, we construct a test bed network and execute scenario-based test.