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DSRC Study Group Introduction

DSRC Study Group Introduction. Dedicated Short Range Communications in the 5.9GHz band. Background.

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DSRC Study Group Introduction

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  1. DSRC Study Group Introduction Dedicated Short Range Communications in the 5.9GHz band Tim Godfrey, Intersil; Broady Cash, ARINC

  2. Background • In 1999, the FCC allocated 75MHz of spectrum at 5.850-5.925 GHz, right above the UNII band, for a “wireless link to transfer information between vehicles and roadside systems” and between vehicle systems. • Congress directed the Department of Transportation to develop a standard to insure device interoperation in the DSRC band. This standard will form the basis for the FCC rules for this band. The Federal Highway Administration chartered ASTM to do the lower layer standards development. • DSRC standard ASTM E2213-02 is based on 802.11a Tim Godfrey, Intersil; Broady Cash, ARINC

  3. FCC Status • Spectrum allocated in 1999 • NPRM on rules underway in 2003 • Comments have been filed • Non-controversial, general agreement to approach and use of ASTM E2213 standard as basis for rules. • Ruling expected by end of 2003 Tim Godfrey, Intersil; Broady Cash, ARINC

  4. ASTM DSRC Standard Status • ASTM E2213-02 is based on 802.11a • Was published in 2002 (www.astm.org) • 2003 revision completed ballot in June 2003 • 2003 revision to be published in August 2003 • Written as an amendment to the 802.11a amendment • Significant PHY changes, but specifically designed to allow industry standard 802.11a chips to support DSRC • Minor MAC function additions – simple firmware updates to industry standard 802.11 firmware • ASTM/DSRC wants to move E2213 into IEEE 802.11 • E2213 is difficult to read because it does not contain the complete text • Will be difficult to maintain with references IEEE 802.11 and IEEE 802.11a. Tim Godfrey, Intersil; Broady Cash, ARINC

  5. DSRC specific IEEE Standards • DSRC is a complete communication protocol • not just MAC and PHY • IEEE standards are being developed for higher layers: • IEEE P1556 Draft Standard for Dedicated Short Range Communications (DSRC) Security • IEEE P1609.1 Draft Standard for Dedicated Short Range Communications (DSRC) Resource Manager • IEEE P1609.2 Draft Standard for Dedicated Short Range Communications (DSRC) Application Services and and Management Entity • IEEE P1609.3 Draft Standard for Dedicated Short Range Communications (DSRC) IP interface (Network Service) • IEEE P1609.4 Draft Standard for Dedicated Short Range Communications (DSRC) Medium Access Control (MAC) Extension and Management Entity (MXME) Tim Godfrey, Intersil; Broady Cash, ARINC

  6. Core DSRC Architecture SME UPPER LAYER MGMT APPLICATION MANAGER OTHER APPLICATIONs APPLICATION SERVICE LAYERS 5 - 7 TRANSPORT SERVICE LAYERS 4 NETWORK MANAGER LAYER 3 NETWORK SERVICE LAYER 3 LAYER 2 - LLC MXME LAYER 2 - DSRC MAC EXTENSION MLME PLCP/ PLME LAYER 2 - DSRC MAC LAYER 1 - DSRC PHY Tim Godfrey, Intersil; Broady Cash, ARINC

  7. Core DSRC Standards • User selected • IEEE 1609.1 • IEEE 1609.2 • IETF RFC 768/793 • IEEE 1609.3 • IEEE 802.2 • IEEE 1609.4 • ASTM E2213-02 Implements a useful process Provides commands and a memory structure that applications can use to store information on a DSRC radio Sends properly formatted data to establish communication links. Collects application registration information to build link establishment messages. UDP - Routes data to the correct application (port) TCP - adds an error and sequence checking service Routes data to the correct device on a network or across multiple networks Routes data to the correct communications stack on a device Routes data to the correct communications channel on a device Implements the physical transfer of data over the air while exercising the proper controls to minimize data collisions and detect errors when they occur. Station Management provides the management data access to all layers. • Application – • Application Manager – • Application Service – • Transport Service – • Network Service – • Logical Link Control – • MAC Extension – • Physical and Medium Access Control (MAC) - Tim Godfrey, Intersil; Broady Cash, ARINC

  8. Applications • Safety • Intersection collision warning, stopped vehicle hazard warning, emergency vehicle approach warning, work zone warning, road hazard warning, etc. • Information: “Roadside Kiosk” • Traffic advisory, road construction, weather conditions, upcoming exit services, map updates, etc. • Internet Access Hot-Spots • Provided by service stations, truck stops, retail store parking lots, etc. • Entertainment • Music & video download – Service providers and personal • Integration with home wireless LAN • Fleet Management • Port of entry, asset tracking, security, scheduling • Electronic Payment • Toll plazas, service stations, drive-through venues, truck stops, etc. Tim Godfrey, Intersil; Broady Cash, ARINC

  9. North American Band Plan US, Canadian, and Potential Mexican DSRC Allocation Control Channel Service Channels High Availability/Low Latency Primarily Public Safety High-power App. US Spread Spectrum Allocation “Reserved” for harmonization with potential extension of the UNII band Optional 20 MHz Optional 20 MHz Ch 180 Ch 182 Ch 184 Ch 172 Ch 178 Ch 174 Ch 176 5.875 5.880 5.905 5.910 5.850 5.855 5.860 5.865 5.870 5.885 5.890 5.895 5.900 5.920 5.925 5.825 5.845 5.835 5.830 5.915 5.840 Frequency (GHz) 10 MHz Channels with 20 MHz combination options Tim Godfrey, Intersil; Broady Cash, ARINC

  10. 5 GHz Band International Plan Europe Japan N. America ISM band CALM M5 Unlicen. W-LAN Regionally available: ISM+ shared unlicenced Dedicated ITS (DSRC) Tim Godfrey, Intersil; Broady Cash, ARINC

  11. Other Related Organizations • US Department of Transportation • Federal Highway Administration • National Highway Traffic Safety Administration • ITS America • AASHTO – American Association of State Highway And Transportation Officials Tim Godfrey, Intersil; Broady Cash, ARINC

  12. Uniqueness of DSRC • Communication with vehicles at high velocities • Capability to communicate with all units • Capability to process individual broadcast messages • Extremely low latency tolerance – measured in single and dual digit milliseconds • Multiple channel operation during each session • Extremely close channel spacing • Widely varying unit power levels • Multiple overlapping uncoordinated communication zones (usually on different channels) • Operation in the automotive environment • Licensed operation Tim Godfrey, Intersil; Broady Cash, ARINC

  13. Relationship to 802.16 and 802.20 • How is this standard different when compared to 802.16 or 802.20? • 802.16 and 802.20 are carrier oriented. The connection and data service is what is sold. • Typically operating in licensed bands. • Targeting ranges of many kilometers. • DSRC is application and safety oriented. • The selling of “service” (as a carrier) is prohibited by FCC rules. • Short range (<1KM), dynamic, ad-hoc connections • Very low latency communication • Rapid initialization • Provides direct vehicle to vehicle communications Tim Godfrey, Intersil; Broady Cash, ARINC

  14. Relationship to 4.9GHz • 802.11J is addressing the 4.9GHz spectrum in Japan. • Some users have requested a 10MHz channelization option, which is proposed to be the same as DSRC • Leverage work already being done for Japanese requirement • In the US, 4.9GHz is allocated for public safety. • The National Public Safety Telecommunications Council administrates this spectrum • They are considering proposals to coordinate with DSRC modulation and channelization. Tim Godfrey, Intersil; Broady Cash, ARINC

  15. What will happen in 802.11? • The ASTM DSRC committee is asking 802.11 to form a Study Group • To develop an amendment to extend and modify the 5GHz PHY for the DSRC band, and incorporate necessary MAC changes. • MAC changes apply only to the use of this specific PHY in this band. Tim Godfrey, Intersil; Broady Cash, ARINC

  16. What changes to 802.11? • DSRC is based on the 11a and 11g OFDM PHY, with the following primary differences: • The frequency range is 5.850-5.925 GHz • The channels are 10MHz wide, with two 20MHz options • The spectral mask has three additional configurations referenced to power output • Additional classes of operation were added to the adjacent channel rejection requirements. • An automotive environment temperature class is added • Specific channels have unique rules for operation • Almost all units acquire the link on the “Control Channel” then switch to other channels for data transfer. • A modified IBSS mode is used for rapid link acquisition • For privacy reasons, the MAC address is random • Using Locally Administered address space • An algorithm to resolve duplicates is provided (a rare occurrence: 1 in 2^46 probability) Tim Godfrey, Intersil; Broady Cash, ARINC

  17. Possible Timeline • July 2003 • Meet in WNG • Submit and approve WG motion form Study Group • September 2003 • SG meets • Write PAR and 5 Criteria, approve in WG • November 2003 • 802 ExCom approves PAR and 5 Criteria • Begin work on first draft • January 2004 • Issue first draft to Letter Ballot Tim Godfrey, Intersil; Broady Cash, ARINC

  18. Motion • Request that an 802.11 Study Group be formed to develop an amendment to extend and modify the 802.11 5GHz PHY to support DSRC technology inthe 5.9GHz DSRC (Dedicated Short Range Communication) band, and incorporate necessary MAC changes. • Passed in WNG • 40 for : 0 against : 31 abstain Tim Godfrey, Intersil; Broady Cash, ARINC

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