1 / 14

IEEE Std. 802.16 Technique Overview

系統暨網路管理實驗室 Systems & Network Management Lab. IEEE Std. 802.16 Technique Overview. nmgmt.cs.nchu.edu.tw. Reporter ：黃文帥 2007/09/18. 1. 2. 3. What is WiMAX. Physical Layer. Frame Structure. Contents. What is WiMAX. Scope: - Specifies the air interface, MAC (Medium Access Control),

jerome
Télécharger la présentation

IEEE Std. 802.16 Technique Overview

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 系統暨網路管理實驗室Systems & Network Management Lab IEEE Std. 802.16 Technique Overview nmgmt.cs.nchu.edu.tw Reporter：黃文帥 2007/09/18

  2. 1 2 3 What is WiMAX Physical Layer Frame Structure Contents LOGO

  3. What is WiMAX • Scope: - Specifies the air interface, MAC (Medium Access Control), PHY (Physical Layer). • Purpose: - Enable rapid worldwide deployment of cost-effective broadband wireless access product. - Facilitate competition in broadband access by providing alternatives to wireless broadband access. • Main advantage: - Fast deployment, dynamic sharing of radio resources and low cost. LOGO

  4. What is WiMAX Deployment LOGO

  5. What is WiMAX Adaptive Modulation • Maximize throughput. • Minimize average power. • Minimize average bit error rate. LOGO

  6. What is WiMAX 802.11 vs 802.16 • 802.11 is not strictly synchronized. 802.16 is a slotted system and all the transmission must be synchronize. • 802.11 uses two-way (Data/ACK) or four-way (RTS/CTS/Data/ACK) handshaking to access channel and transmit data. 802.16 uses a three-way handshaking to set up connection before data transmission (Request/Grant/Transmit). • 802.11 does not distinguish control channel and data channel. In 802.16, the control channel and data channel are separated. • In 802.11, a station must compete for every packet. In 802.16, a station can reserve multiple slots for the following packets. LOGO

  7. Physical Layer Introduction • Support framing. • Support both Time Division Duplex (TDD) and Frequency Division Duplex (FDD), as well as half-duplex FDD (H-FDD). • Burst transmission format which supports adaptive burst profiling. - Data allocations within a frame are referred as bursts. - Transmission parameters, including the modulation and coding schemes (burst profiles), may be adjusted individually to each SS on a frame-by-frame basis. - Burst profiles are broadcast via MAC management messages Downlink Channel Descriptor (DCD) and Uplink Channel Descriptor (UCD) periodically. - The actual transmission bandwidth is allocated by BS and broadcast in MAC management messages Downlink MAP (DL-MAP) and Uplink MAP (UP-MAP) in each frame. - Adapt to multiple modulation levels：BPSK, QPSK, QAM-16, QAM-64. LOGO

  8. Physical Layer PHY Duplexing Option • TDD - The UL and DL transmissions occur at different times and usually share the same frequency. (SS does not receive and transmit data at the same time) - A TDD frame has a fixed duration and contains one DL and one UL subframe, whose durations can vary. • FDD - The UL and DL channels are located on separate frequencies. - A fixed duration frame is used for both UL and DL transmissions. - The H-FDD SS does not receive and transmit data at the same time. LOGO

  9. Physical Layer TDD Frame Structure • PS (Physical Slot) - A unit of time, depend on the PHY specification, for allocating bandwidth. LOGO

  10. Physical Layer FDD Bandwidth Allocation LOGO

  11. Frame Structure Downlink Subframe • TTG/RTG (Transmit/Receive Transition Gap) - A gap between the downlink burst and the subsequent uplink burst in a time division duplex (TDD) transceiver. LOGO

  12. Frame Structure Uplink Subframe • SSTG (Subscriber Station Transition Gap) LOGO

  13. Frame Structure OFDMA Frame Structure LOGO

  14. Thank You !

More Related