Bo Li, Hong Kong University of Science and TechnologyYang Qin and Chor Ping Low, Nanyang Technological University

Choon Lim Gwee, Republic Polytechnic

Speaker : Yu-Ping ChenAdviser : Quincy Wu

Date : Nov.1

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Introduction

Mobile WiMAX

INTEROPERABILITY OF IEEE 802.16 AND IEEE 802.11

Conclusion

Reference

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IEEE 802.16 - Worldwide Interoperability for Microwave Access (WiMAX)

IEEE 802.16, a solution to broadband wireless

access (BWA)

BWA include the medium access control (MAC) and physical (PHY) layers

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the PHY layer includes orthogonal frequency-

division multiplexing (OFDM)

OFDM is achieved by providing multiplexing on users’ data streams on both uplink and downlink transmissions.

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IEEE 802.16 published in 2001. The frequency range of 10–66GHz maximum bandwidth of 120 Mb/s maximum transmission range of 50km.

Initial, only supports line-of-sight (LOS) transmission and thus does not seem to favor deployment in urban areas.

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IEEE802.16a-2003 supports NLOS and OFDM

at PHY layers. But it covers too many profiles and PHY

layers, which can lead to potential interoperability problems.

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IEEE802.16-2004 provides technical specifications for the PHY and MAC layers for fixed wireless access and addresses the first or last-mile connection in wireless metropolitan area networks (WMANs).

But it seems to IEEE 802.11 WLAN

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IEEE 802.16e released in 2007 AD has added mobility support.

This is generally referred to as mobile WiMAX.

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Mobile WiMAX adds significant enhancements:

It improves NLOS coverage by utilizing advanced antenna diversity schemes and hybrid automatic repeat request (hARQ).

It adopts dense subchannelization, thus increasing system gain and improving indoor penetration.

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Mobile WiMAX adds significant enhancements:

It uses adaptive antenna system (AAS) and multiple input multiple output (MIMO) technologies to improve coverage.

It introduces a downlink subchannelization scheme, enabling better coverage and capacity trade-off.

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QoS end-to-end IP-based service mapping and

also provides mechanisms for optimal scheduling on a frame-by-frame basis.

Flexible spectrum allocation different channelization from 1.25 to 20

MHz comply with diverse requirement in different countries

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Enhanced security in that new authentication was added (3DES or AES 加密，加上 EAP)

**Wi-Fi WPA2 標準的 PEAP 認證與 AES 加密 **

The MIMO antenna techniques support peak rates of 63 Mb/s in downlink

and 28 Mb/s uplink per sector

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Sleep mode

It minimize a mobile user’s power consumption

and flexibility that allows a mobile user to scan BSs to collect handoff related information.

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Idle mode A mobile user can traverse multiple BSs and

periodically capture downlink broadcast messages without registration to any specific BS.

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Hard Handoff (HHO) HHO is mandatory, while FBSS and MDHO

are optional.

Fast Base Station Switching (FBSS) FBSS a mobile user only communicates with

the anchor BS, and the handoff involves the transition to a new anchor BS.

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Macrodiversity Handover(MDHO) MDHO a mobile user communicates with all

BSs in the active set, and different operations are defined for uplink and downlink transmission during handoff.

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High data rate and coverage using a singlefrequency network

Flexible radio resource allocation Low power consumption Supporting data, audio, and video multicast Low channel switch time

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standard 802.16 802.16a-2003 802.16-2004 802.16e

應用模式 固定式應用 (取代寬頻設備 ) 移動式應用應用方向 Last Mile & Backhaul Mobile Device

頻段 10~66GHz 2~11GHz 2~6 GHz

傳輸條件 LOS NLOS NLOS

傳輸速率 32~134Mbps 75Mbps 15Mbps

調變技術 QPSK 、 16QAM 、 64QA

M

QPSK 、 16QAM 、 64QAM

（採 256 Subcarrier OFDM）

QPSK 、 16QAM 、64QAM（採 257

Subcarrier OFDM ）

移動性 固定性 固定性 移動性傳輸距離 1~ 5Km 6~10Km(最大 50Km) 1~5 Km

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For example UGS QoS parameters in IEEE 802.16 be

mapped to the Access Category 3 EDCA queue in IEEE 802.11e to provide sufficient QoS?

Rerouting packets from the WiMAX BS to the 802.11e AP. the packet reroute time is sufficiently short to handle any QoS transmission latency caused by the handover?

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　 802.11 802.16 技術差別

通信距離

小於 100 公尺（增加 Access Point 可使覆蓋距離增加）

可達 50Km ，典型小區半徑為 6-10Km

通過 256 FFT 的實施， 802.16 物理層容忍較大的多重路徑、反射； 802.11 是64FFT

覆蓋 室內性能最優，短距離

室外 NLOS 性能標準，支持先進天線技術 :AAS 和 MIMO

802.16 系統的總系統效益高，通過障礙物的穿透能力強，傳輸距離遠

可擴展性

用於 LAN ，用戶可從一個擴展到數十個，每 CPE 一個用戶；固定通道頻寬（ 20MHz ）

可以有效地支援一到數百個 CPE ，每一 CPE後面的用戶不受限制；彈性調整 channel access 寬度，從1.5MHz-20MHz

802.11 中的 MAC 協議使用CSMA/CA 協議， 802.16 則使用動態 TDMA

802.11 只能用於不需牌照的頻帶，通道數量有限。 802.16 可以使用所有能用的頻率，多通道支持蜂窩 (cell) 結構

Bit 率 2.7bit/s/Hz

5bit/s/Hz ，在 20MHz通道內高達 100Mbit/s

高效分配加靈活的糾正使更有效的頻譜使用

QoS 無 QoS 支援QoS 內含於 MAC ，達到語音 / 影像及區分其他服務水平

802.11 ： MAC 上（ CSMA/CA ），基本上是無線乙太網802.11 ： 802.16 動態 TDMA的 MAC ，頻寬需分配

It can be expected that future work will focus on the mobility aspect and interoperability of mobile WiMAX with other wireless technologies.

The cost of infrastructure and competition from other technologies such as 3G/4G.

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A Survey on Mobile WiMAX AuthorsBo Li, Hong Kong University of Science an

Technology

Yang Qin and Chor Ping Low, Nanyang Technological University

Choon Lim Gwee, Republic Polytechnic

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