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DSRC & WAVE. Overview. DSRC Dedicated Short-Range Communications ASTM Standard E2213-03, based on 802.11a ITS communications on 5.9/5.8GHz band WAVE Wireless Access in Vehicular Environments Mode of operation used by IEEE 802.11 devices to operate in the DSRC band IEEE 802.11p
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Overview • DSRC • Dedicated Short-Range Communications • ASTM Standard E2213-03, based on 802.11a • ITS communications on 5.9/5.8GHz band • WAVE • Wireless Access in Vehicular Environments • Mode of operation used by IEEE 802.11 devices to operate in the DSRC band • IEEE 802.11p • Based on ASTM Standard E2213-03 • Currently draft
IEEE P1556 • Standard for Security and Privacy of Vehicle/Roadside Communication Including Smart Card Communication • Is now replaced by IEEE 1609.2
IEEE P1609/WAVE • IEEE P1609 family are standards for WAVE • Defines…for vehicular wireless communication • Architecture, Communications model, Management structure, Security mechanisms, Physical access • Architectural components • On Board Unit (OBU) • Road Side Unit (RSU) • WAVE interface
IEEE P1609/WAVE CCH & SCH • WAVE devices shall be able to accommodate an architecture that supports a Control Channel (CCH) and multiple Service Channels (SCH) • CCH • Transmit WAVE Short Messages (WSM) • Announce WAVE services • SCH • Application interactions/transmissions
Synchronization • To make sure all devices are monitoring CCH during CCH interval • IEEE 1609.2 Security • Single-channel device • Must have Coordinated Universal Time (UTC) • Ex: GPS pulse per second (PPS) • Or it shall continuously monitoring CCH • Multi-channel device • Monitor CCH • Ex: Timestamp field of IEEE 802.11
IEEE 1609 Sync Tolerance • Guard interval is used for synchronization
IEEE 1609/WAVE • IEEE 1609.1 • Resource Manager • IEEE 1609.2 • Security Services for Applications and Management Messages • IEEE 1609.3 • Networking Services • IEEE 1609.4 • Multi-Channel Operations
IEEE 1609.3 Data Services • Logical Link Control (LLC) • IPv6 • UDP & TCP • WAVE short message (WSM) and protocol (WSMP)
IEEE 1609.3 Management Services • Application Registration • Register application to WAVE Management Entity (WME) so service flow can map to correct IP address & port • WAVE Basic Service Set (WBSS) management • WBSS actions • Ex: Joining & ending a WBSS • WBSS parameters management • Ex: SSID, MAC address, SCH number, Timestamp
IEEE 1609.3 Management Services • Channel usage monitoring • Ex: QoS, avoid using congested channel • IPv6 configurations • Received channel power indicator (RCPI) monitoring • Ex: provide RCPI for applications • Management information base (MIB) maintenance • Management parameters
IEEE 1609.4 User Priority (UP) • Use IEEE 802.11e EDCA mechanism • Mapping UP to Access Category Index (ACI)
IEEE 1609.4 UP on CCH & SCH CCH SCH
IEEE 1609.4 Channel Coordination • Channel coordination requires synchronization • A guard interval is at the beginning of each synchronization interval • Media busy is declared during guard interval
IEEE 802.11p • Define enhancements to 802.11 required to support ITS applications • Lower layer of WAVE • Supports two different stacks • IPv6 • only on SCHs (not CCH) • WAVE Short Message Protocol (WSMP) • can be sent on any channel • allows applications to directly control physical characteristics
IEEE 802.11p • Communication between 802.11 STAs … • Without becoming a member of a BSS is possible • Direct & Immediate • Avoid the latency caused by BSS association • May use a dedicated frequency band
IEEE 802.11p MAC • DCF – CSMA/CA • IBSS & Infrastructure • Communication outside BSS • HCF contention-based channel access (EDCA) • EDCA is an enhanced variant of DCF • EDCA parameters • Outside BSS: default • Inside BSS: given by associated BSS or AP
DSRC Worldwide - ISO • ISO (International Organization for Standardization) • Working Group 15 • Upper layer • Working Group 16 • Lower layer
DSRC Worldwide - Europe • CEN (European Committee for Standardization) • EN 12253:2004 Dedicated Short-Range Communication - Physical layer using microwave at 5.8 GHz (review) • EN 12795:2002 Dedicated Short-Range Communication (DSRC) - DSRC Data link layer: Medium Access and Logical Link Control (review) • EN 12834:2002 Dedicated Short-Range Communication - Application layer (review) • EN 13372:2004 Dedicated Short-Range Communication (DSRC) - DSRC profiles for RTTT applications (review) • EN ISO 14906:2004 Electronic Fee Collection - Application interface
DSRC Worldwide - Japan • ARIB (Association of Radio Industries and Businesses, 電波產業會) • STD-T55: Electronic Toll Collection System • STD-T75: Dedicated Short-Range Communication System • STD-T88: DSRC Application Sub-Layer
DSRC Worldwide - US The lead organization is ASTM Old – 915MHz New – 5.9GHz Range to 1000 meters Data rate 6 to 27 mbps Designed for general internet access, can be used for ETC 7 licensed channels Uses open off-the-shelf chip set & software Vehicle to roadside & vehicle to vehicle Command-response & peer to peer • Range < 30 meters • Data rate = 0.5 mbps • Designed for ETC, but can be used for other applications • Single unlicensed channel • Requires special (custom) chip set & software • Vehicle to roadside • Command-response
US DSRC Spectrum • 75 MHz band has been allocated by FCC at 5.9 GHz • Initial band use rules accepted • No auction expected • Band allows both safety and commercial applications to coexist
US DSRC Channel Plan IEEE 802.11a/RA WB - 52 carrier OFDM /w 48 data carriers, 10 MHz channels Control Channel Optional 20 MHz Optional 20 MHz US Spread Spectrum Allocation Uplink Downlink Ch 172 Ch 174 Ch 176 Ch 178 Ch 180 Ch 182 Ch 184 Canadian Special License Zones* 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) * - The channels overlapping these zones may be restricted in some locations in Canada. In these cases use channels 1, 2, and 3 in their place.
US DSRC Performance Envelope ~ ~ 33 30 Data Transfer and Internet Access Services 27 5850 - 5925 MHz Band Performance Envelope 24 Data Rate (Mbps) (Approximate) 21 18 12 Emergency Vehicle Services Safety Message Services 9 6 3000ft↓ Toll and Payment Services 3 902 - 928 MHz Band Performance Envelope 0 600 800 200 400 1000 1400 1600 1800 2400 2800 3000 1200 2000 2200 2600 3200 3400 3600 0.5 Mbps Range (ft)
Specific Applications Private and Public Safety - Short Range ALL VEHICLES Private and Public Safety - Short Range CVO • ACCESS CONTROL • PROBE DATA COLLECTION • TRAFFIC INFORMATION • TOLL COLLECTION • GAS PAYMENT • DRIVE-THRU PAYMENT • DATA TRANSFER (IDB, J1708, J1939, PCI, etc.) • ATIS DATA • DIAGNOSTIC DATA • REPAIR-SERVICE RECORD • VEHICLE COMPUTER PROGRAM UPDATES • MAP and MUSIC DATA UPDATES • RENTAL CAR PROCESSING • MAINLINE SCREENING • BORDER CLEARANCE • ON-BOARD SAFETY DATA TRANSFER • UNIQUE CVO FLEET MANAGEMENT • DRIVER’S DAILY LOG • VEHICLE SAFETY INSPECTION • TRANSIT VEHICLE DATA TRANSFER (gate) • TRANSIT VEHICLE REFUELING • LOCOMOTIVE FUEL MONITORING • ROLLOVER WARNING • LOW BRIDGE WARNING Private and Public Safety - Large Zone Public Safety - Extended Range • TOLL COLLECTION • TRANSIT VEHICLE DATA TRANSFER (yard) • LOCOMOTIVE DATA TRANSFER • CVO TRUCK STOP DATA TRANSFER • IN-VEHICLE SIGNING • WORK ZONE WARNING • HIGHWAY/RAIL INTERSECTION WARNING • ROAD CONDITION WARNING • INTERSECTION COLLISION AVOIDANCE • VEHICLE TO VEHICLE • VEHICLE STOPPED or SLOWING WARNING • VEHICLE-VEHICLE COLLISION AVOIDANCE Public Safety - Intersection and Emergency • EMERGENCY VEHICLE SIGNAL PREEMPTION • TRANSIT VEHICLE SIGNAL PRIORITY • EMERGENCY VEHICLE VIDEO RELAY • EMERGENCY VEHICLE APPROACH WARNING
Illustrations of some US DSRC APPs • Roadside Unit Placement • Good News/ Bad News • General Internet Access • On-Demand/Dynamic Navigation • Traffic Advisories • Use Vehicles as Traffic Probes • Travel Assistant • Relayed & Delayed Transmission • Information or Transaction Request • Information Requested over Internet • Data Downloaded Later Pictures of these applications are selected from Lee Armstrong’s DSRC introduction website
Roadside Unit Placement Sometimes someplace instead of everywhere always
Good News/ Bad News Can be targeted to specific lanes, directions of travel but not for wide area coverage
Relayed & Delayed Transmission • Information or Transaction Request • Information Requested over Internet • Data Downloaded Later