• Title/Summary/Keyword: IEEE802.16e Standard

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WiMAX Security Mechanism for Minimizing Performance load of Base Station (베이스 스테이션의 성능부하를 최소화하기 위한 WiMAX 보안 메커니즘)

  • Jeong, Yoon-Su;Kim, Yong-Tae;Park, Gil-Cheol;Lee, Sang-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.10
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    • pp.1875-1882
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    • 2008
  • Nowadays, usage of mobile unit which has a characteristic of low cost and high efficiency is being generalized because of frequent use of internet-based variable service and application in IEEE 802.16 WiMAX. A study for handling a security problem of high speed internet service is rising while the use of a mobile is being generalized. This paper suggests a security mechanism which provides safety from certification load of SS and a security attack as well as a basic function which is provided from IEEE 802.16e standard to satisfy security demand of IEEE802.16 WiMAX. The proposed mechanism exchangeskey material information for TEK and data code by using 난수(?) and secret value created by SS and BS, also reduces capacity load of BS not to perform an additional certificate procedure of BS by using the early certification information and certificate of SS.

Design of microstrip antenna for Dual-band applications (이중대역용 마이크로스트립 안테나 설계)

  • Park, Sea-Pil;Kim, Kab-Ki
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.5
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    • pp.213-217
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    • 2012
  • In this paper, we design dual-band microstrip antenna for IEEE 802.16e mobile WiMAX standard IEEE 802.11 WLAN band at the same time. To solve interference at the desired operating frequency band, impedance matching is improved and simple production method showed the characteristics of the omni-directional and compact size. The proposed structure is considered to bring the effect of the installation costs, and show the antenna for dual-band communication.

Design of Efficient FFT Processor for IEEE 802.16e Mobile WiMax Systems (IEEE 802.16e Mobile WiMax 시스템을 위한 효율적인 FFT 프로세서 설계)

  • Park, Youn-Ok;Park, Jong-Won
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.97-102
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    • 2010
  • In this paper, an area-efficient FFT processor is proposed for IEEE 802.16e mobile WiMax systems. The proposed scalable FFT processor can support the variable length of 128, 512, 1024 and 2048. By reducing the required number of non-trivial multipliers with mixed-radix (MR) and multi-path delay commutator (MDC) architecture, the complexity of the proposed FFT processor is dramatically decreased without sacrificing system throughput. The proposed FFT processor was designed in hardware description language (HDL) and synthesized to gate-level circuits using 0.18um CMOS standard cell library. With the proposed architecture, the gate count for the processor is 46K and the size of memory is 64Kbits, which are reduced by 16% and 27%, respectively, compared with those of the 4-channel radix-2 MDC (R2MDC) FFT processor.

Performance Analysis of the MAC protocol for the Broadband Wireless Access System (광대역 무선 접속 시스템의 MAC 프로토콜 성능분석)

  • Cho Kwang-Oh;Hwang You-Sun;Park Ae-Soon;Lee Jong-Kyu
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.6 s.336
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    • pp.33-40
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    • 2005
  • In this paper, we analyzed the DRMA(Dynamic Reservation Multiple Access) protocol with Rayleigh fading, shadowing, and capture effect for the Broadband fireless Access System. We consider the TDMA-based protocols, since these are based on the standard for IEEE 802.16 WMAN, IEEE 802.20 MBWA, and ETSI HIPERLAN//2. The results of analytical model will be apply the development of collision resolution algorithm, scheduling algorithm and the dynamic change of system parameters.

Automatic Adaptive Algorithm to Optimize OFDMA Initial Ranging Contention Process (OFDMA 초기 레인징 경쟁 프로세스의 최적화를 위한 자동적응형 알고리즘)

  • Kim, Ha-Jeong;Jang, Bong-Seog;Lee, Seong-Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.7A
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    • pp.540-547
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    • 2009
  • In this paper, we work for the efficient use of the initial ranging contention slot in OFDMA based wireless mobile networks. Specially, the collision reduction method using an automatic adaptive optimal algorithm is studied for initial ranging contention slot used at initial connection of the mobile terminals. As a result, we propose the algorithm that achieves the collision minimization and the auto-dynamic slot arrangement of the initial ranging slots. To evaluate the proposed algorithm, we compare the simulation results of IEEE802.16e fixed initial ranging slot allocation method versus the proposed algorithm. The simulator is developed based on the IEEE802.16e standard MAC frame structure and processing procedures. As the simulation results, we can expect the proposed algorithm can be applied for the unmanned coastal base station because the proposed algorithm has the effect of minimizing administration cost for the base station.

Adaptive Scanning Scheme for Mobile Broadband Wireless Networks based on the IEEE 802.16e Standard (802.16e 표준 기반 광대역 무선 이동 망을 위한 동적 스캐닝 기법)

  • Park, Jae-Sung;Lim, Yu-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.151-159
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    • 2008
  • Mobile broadband wireless network is emerging as one of the hottest research areas due to technical advances, and the demands of users who wish to enjoy the same network experience on the move. In this paper, we investigate the handover process at the medium access control (MAC) layer in an IEEE 802.16e-based system. In particular, we identify problems concerned with the scan initiation Process called cell reselection and propose a received signal strength (RSS) estimation scheme to dynamically trigger a scanning process. We show how the RSS estimation scheme can timely initiate a scanning process by anticipating RSS values considering scan duration required.

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An Uplink Scheduling Algorithm for VoIP in IEEE 802.16d Systems (IEEE 802.160에서 상향링크 VoIP 스케줄링 알고리즘 방식 연구)

  • Kang, Min-Seok;Jang, Jae-Shin
    • Journal of the Korea Society for Simulation
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    • v.15 no.3
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    • pp.87-91
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    • 2006
  • With the growth of the internet, the number of wireless internet users has increased continuously up to date. However, mobile communications could not support high speed transmission rate with cheap communication fee and wireless LAN has problems in providing terminal mobility and wide area connectivity, respectively. So the WMAN standard has been newly designed to make up for these limits. The initial 802.16 specification effectively offers a solution for providing fixed users with high speed wireless communication but it does not offer terminal mobility. So the 802.16d and 802.16e have been developed as the next generation solution that can support various PHY layer (SC, SCa, OFDM, OFDMA) and offer the terminal mobility. In this paper, we propose an effective uplink scheduling algorithm for VoIP with using UGS, and we show that our proposed algorithm is superior in view of average delay and management of uplink bandwidth to conventional rtPS algorithm and the scheme in reference, with using NS-2 network simulator.

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Performance Analysis of Timing Synchronization Scheme for AeroMACS System (항공관제통신용 AeroMACS 시스템의 시간 동기 성능 분석)

  • Lee, Eun-Sang;Sohn, Kyun-Gyeol;Park, Youn-Ok;Jung, Yun-Ho
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.255-263
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    • 2012
  • In this paper, the performance evaluation results of the timing synchronization schemes are presented for aeronautical mobile airport communication systems (AeroMACS). AeroMACS, which is based on IEEE 802.16e mobile WiMAX standard, uses the aeronautical frequency band of 5GHz with the bandwidth of 5MHz. The simulation model of AeroMACS is constructed and the evaluation for the timing synchronization performance is performed with the various channel models such as apron (APR), runway (RWY), taxiway (TWY), and park (PRK).

A Design of Multi-Standard LDPC Decoder for WiMAX/WLAN (WiMAX/WLAN용 다중표준 LDPC 복호기 설계)

  • Seo, Jin-Ho;Park, Hae-Won;Shin, Kyung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.2
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    • pp.363-371
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    • 2013
  • This paper describes a multi-standard LDPC decoder which supports 19 block lengths(576~2304) and 6 code rates(1/2, 2/3A, 2/3B, 3/4A, 3/4B, 5/6) of IEEE 802.16e mobile WiMAX standard and 3 block lengths(648, 1296, 1944) and 4 code rates(1/2, 2/3, 3/4, 5/6) of IEEE 802.11n WLAN standard. To minimize hardware complexity, it adopts a block-serial (partially parallel) architecture based on the layered decoding scheme. A DFU(decoding function unit) based on sign-magnitude arithmetic is used for hardware reduction. The designed LDPC decoder is verified by FPGA implementation, and synthesized with a 0.13-${\mu}m$ CMOS cell library. It has 312,000 gates and 70,000 bits RAM. The estimated throughput is about 79~210 Mbps at 100 MHz@1.8v.

Performance Improvement in High SNR for LDPC codes using Power Allocation (전력할당을 통한 LDPC부호의 높은 SNR에서의 성능개선 방법)

  • Lee, Ki-Jun;Chung, Ha-Bong;Im, Ju-Hyuk;Choi, Eun-A;Chang, Dae-Ig
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.10C
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    • pp.935-941
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    • 2007
  • In this paper, we suggest the power allocation method which enhances the performance in high SNR for LDPC codes. In this method, bit power is unequally allocated proportionally to the difference of the degree distributions of variable and check nodes of Tanner graph between practically used codes and the codes optimized by density evolution. Simulation is performed to the codes in IEEE 802.16e standards, and the results show that the proposed method works well in high SNR.