V2X-assisted emergency vehicle transit in VANETs

Vehicular ad hoc networks (VANETs) can support safety-critical applications such as the safe and fast movement of emergency vehicles while preventing crashes, delays, and congestion involving emergency vehicles. A simulation approach to evaluate ambulance transit using VANET capabilities is presented in this paper for a real-life road network taken in and around the University of Missouri–Kansas City, USA. Three different VANET functional scenarios are compared with a base scenario (SC-1) which depicts the present-day traffic pattern and vehicle behaviors. In the three scenarios, the second one (SC-2) adds vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications along with the present-day traffic pattern; ambulances use VANETs simply to announce their arrival. The third scenario (SC-3) provides functionalities for ambulances to rerouting when they learn about a current or an anticipated road congestion. And the fourth scenario (SC-4) adds vehicle rerouting capabilities, so ambulance routes can be sent to vehicles, and they can avoid the ambulance path. Performance results are presented and evaluated for metrics such as delay, packet drop ratio, the average speed of the ambulance, average vehicle density, and ambulance message interval time. From the simulation results, it was observed that the ambulance transit time reduces by 12.52%, 14.65%, and 18.75% for SC-2, SC-3, and SC-4, respectively, as compared with SC-1, while the average ambulance speed increases by 14.49%, 15.57%, and 20.90% for SC-2, SC-3, and SC-4, respectively, when compared with SC-1. This paper provides substantial evidence that VANET capabilities for emergency vehicles can enhance crash protection and reduce the commute time for emergency response.