Vehicle-to-barrier communications; SDR; USRP; Vehicle crash; received power; Delay spread; Doppler spread.

Vehicle-to-barrier (V2B) communications is an emerging communication technology between vehicles and roadside barriers to mitigate run-off-road crashes, which result in more than half of the traffic-related fatalities in the United States. To ensure V2B connectivity, establishing a reliable V2B channel is necessary before a potential crash, such that real-time information from barriers can help (semi-)autonomous vehicles make informed decisions. However, the characteristics of the V2B channel are not yet well understood.