IEEE 802.11p is a draft amendment to the
IEEE 802.11 standard to add wireless access in the vehicular environment (WAVE). It defines enhancements to
802.11 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.
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