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Handover Technology for Vehicular Communications. Date: 2011-01-18. Authors:. Slide 1. Vehicular Communications. V2V(Vehicle-to-Vehicle) applications: Vehicle safety via vehicle multi-hop communications V2I(Vehicle-to-Infrastructure) applications: ITS/Telematics via communications
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Handover Technology for Vehicular Communications Date: 2011-01-18 Authors: Slide 1
Vehicular Communications • V2V(Vehicle-to-Vehicle) applications: • Vehicle safety via vehicle multi-hop communications • V2I(Vehicle-to-Infrastructure) applications: • ITS/Telematics via communications • Basic requirements • Communication schemes: broadcasting, unicasting • Mobility: up to 200km/h • Long packet transmission:~2K bytes • Packet Latency: <100 msec • Networking: V2I, V2V
Standards for Vehicular Communications • WAVE(Wireless Access in Vehicular Environments) • IEEE 802.11p • PHY/MAC Layers • Published in July 2010 • IEEE 1609.x • 1609.1 : Remote management service • 1609.2 : Security services for application and management messages • 1609.3 : Networking services • 1609.4 : Multi-channel operation • 1609.11: Over-the-Air data exchange protocol for ITS • 1609.3,4 & 11: Published in 2010 and 2011 The others: Will be published in 2011
Handover Issues • Vehicles are moving rapidly along roads • Handover occurs often, and handover issues become more important than 802.11 • When OBE enters new RSE, it takes long channel scanning time to carry out handover • Handover may have some specific schemes depending on the road structures • 802.11p does not provide a sufficient answer for handover issue • Fast handover scheme in vehicular environments • Supports continuous communication between RSEs • Provides various services
Implementation of Handover • Communication Setup • IEEE 802.11p • Data rate: QPSK • Txpower: 15~20dBm EIRP • IEEE 1609.3 & 1609.4 • Single PHY RSE & OBE : CCH/SCH alternative access (using PPS) • Adjacent RSUs use common CCH & different SCH for same service ( 1 CCH & 2 SCHs) • L2 Handover by SCH Assignment ( based on RSSI) • Provided Services • V2I: Internet streaming & CCTV (use fixed IP address) • V2V: Safety messages
Communication Environments/Application Scenarios • Busan-Ulsan Express way • Jangan IC ~ Onyang IC (total length 11.0km) • RSE : 5EA, Avg. Distance between RSEs. 1.04 km • Speed • 60km/h(forward) • 100 km/h(reverse) • ITS WC 2010 (SMART HIGHWAY project) RSE #1 RSE #2 RSE #3 RSE #4 RSE #5
Communication Architecture WAVE Service Server RSE0,SVC1, f1 RSE1,SVC1, f2 RSE2,SVC1, f1 RSE1 (CCH:f0, SCH:f2) RSE2 (CCH:f0, SCH:f1) RSE0 (CCH:f0, SCH:f1) SCH:f1 SCH:f2 SCH:f2 SCH:f1 SCH:f1
RSSI Measurements • Vehicle speed: 60km/h • Changing of RSSI color: Handover occurs
Next Step in Vehicular Communications • Consider • Service needs • Provide various services including multimedia service • Continuous CCTV, Web browsing • Fast & Seamless handover scheme with 802.11p • Support L3 handover • Provide lossless packet forwarding mechanism • Support vertical handover • Support continuous communications with various media (cellular, WiBro(WiMax), WAVE and Etc.)
Straw Poll Q. Should IEEE 802.11 WNG receive further presentations on the topic of handover technology for vehicular communications? • Yes : 12 • No : 1 • Abstain : 13