Wireless System Wireless System Generations 802 11 XSTANDARD

Wireless System

Wireless System Generations

802. 11 X-STANDARD standard 802. 16 a 802. 16 -2004 802. 16 e 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 10~66 GHz 2~11 GHz 2~6 GHz 傳輸條件 LOS NLOS 傳輸速率 32~134 Mbps 75 Mbps 15 Mbps 調變技術 QPSK、16 QAM、 64 QAM QPSK、16 QAM、64 QAM （採 256 Subcarrier OFDM） QPSK、16 QAM、64 QAM （採 257 Subcarrier OFDM） 移動性 固定性 移動性 傳輸距離 1~3 Mile 4~6 Mile(最大 30 Mile) 1~3 Mile

Wireless Access Network § Base Station (BSs) § Subscriber Station (SSs) § Mobile Users

Wireless Access Network

Reference Model

Wi. MAX PHY OFDM

Wi. MAX PHY OFDM

Wi. MAX PHY

Wi. MAX PHY

Wi. MAX PHY

Wi. MAX MAC Provide Network Access • Address the Wireless environment – e. g. , very efficient use of spectrum • Broadband services – Very high bit rates, downlink and uplink – A range of Qo. S requirements – Ethernet, IPv 4, IPv 6, ATM, . . . • Likelihood of terminal being shared – Base Station may be heavily loaded • Security • Protocol-Independent Engine – Convergence layers to ATM, IP, Ethernet, . . . • Support both TDD and FDD in the PHY

Wi. MAX MAC Point-to-Multipoint • Metropolitan Area Network • Connection-oriented • Supports difficult user environments – High bandwidth, hundreds of users per channel – Continuous and burst traffic – Very efficient use of spectrum • Protocol-Independent core (ATM, IP, Ethernet, …) • Balances between stability of contentionless and efficiency of contention-based operation • Flexible Qo. S offerings – CBR, rt-VBR, nrt-VBR, BE, with granularity within classes • Supports multiple 802. 16 PHYs

Wi. MAX MAC

Wi. MAX MAC Service-specific Convergence Sublayer 該子層經由Convergence Sublayer (CS) SAP將MAC CPS與更高層協定互連，在 802. 16 -2004標準中，有兩種CS規格， ATM(Asynchronous Transfer Mode)CS與用於所有封包協定包 括IP或Ethernet的Packet CS。ATM CS使 802. 16系統可與ATM 網路接取，系統同時支援虛擬路徑(Virtual Path，VP)與虛擬通路 (Virtual Channel，VC)，Packet CS則可使 802. 16系統與所有以 封包協定為基礎的系統進行接取。

Wi. MAX MAC Service Data Unit (SDU) – Data units exchanged between adjacent layers • Protocol Data Unit (PDU) – Data units exchanged between peer entities • Connection and Connection ID – a unidirectional mapping between MAC peers over the airlink (uniquely identified by a CID) • Service Flow and Service Flow ID – a unidirectional flow of MAC PDUs on a connection that provides a particular Qo. S (uniquely identified by a SFID)

Wi. MAX MAC