IEEE 802.11p is an approved amendment to the IEEE 802.11 standard to add wireless access in vehicular environments (WAVE). It defines enhancements to 802.11 (the basis of products marketed as Wi-Fi) required to support Intelligent Transportation Systems (ITS) applications. This includes data exchange between high-speed vehicles and between the vehicles and the roadside infrastructure in the licensed ITS band of 5.9 GHz (5.85-5.925 GHz). IEEE 1609 is a higher layer standard on which IEEE 802.11p is based.[1]
802.11p will be used as the groundwork for Dedicated Short Range Communications (DSRC), a U.S. Department of Transportation project based on the ISO Communications, Air-interface, Long and Medium range (CALM) architecture standard looking at vehicle-based communication networks, particularly for applications such as toll collection, vehicle safety services, and commerce transactions via cars. The ultimate vision is a nationwide network that enables communications between vehicles and roadside access points or other vehicles. This work builds on its predecessor ASTM E2213-03.[2]
The 802.11p Task Group was formed in November 2004. Lee Armstrong was chair and Wayne Fisher technical editor. Drafts were developed from 2005 through 2009. By April 2010 draft 11 had been approved by 99% affirmative votes and no comments.[3] The approved amendment was published July 15, 2010.[4] Its title was "Amendment 6: Wireless Access in Vehicular Environments".[4]
In August 2008 the European Commission allocated part of the 5.9 GHz band for priority road safety applications and inter-vehicle, infrastructure communications.[5] The intention is that compatibility with the USA will be ensured even if the allocation is not exactly the same; frequencies will be sufficiently close to enable the use of the same antenna and radio transmitter/receiver.
Simulations published in 2010 predict delays of at the most tens of milliseconds for high-priority traffic.[6]
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