A New Hierarchical and Adaptive Protocol for Minimum-Delay V2V Communication

The majority of vehicle-to-vehicle (V2V) protocols presented in the literature utilize a combination of controlled access techniques (e.g., TDMA, FDMA, CDMA) to provide prioritized access to the communication medium. While these protocols split the capacity of the communication link to support a maximum number of users with different priority levels, our work utilizes a combination of CDMA and TDMA techniques to increase the number of concurrent users sharing the bandwidth. The proposed protocol provides an adaptive scheme that classifies the vehicle's messages as "urgent" or "non-urgent" based on its statistical parameters (e.g., speed, acceleration, directional stability) and the state of its neighboring vehicles (e.g., normal or urgent) . Furthermore, the proposed protocol achieves intelligent scheduling and allocation of messages and the underlying bandwidth to minimize the end-to-end communication delay and the costs associated with the deployment of vehicle infrastructure integration (VII) without the need for road-side equipment.