An SDMA-Based Mechanism for Accurate and Efficient Neighborhood-Discovery Link-Layer Service

Neighborhood-discovery link-layer service is provided by beaconing, which denotes the process of periodically broadcasting status information. It allows vehicles to be aware of their surroundings. The availability of neighborhood knowledge guarantees accurate estimation of safety-related situations and helps to make strategic decisions based on assumed fresh information. Beacon messages share the same channel (control channel, CCH) as safety messages and are sent with no schedule; this may lead to severe contention and packet loss, which can be dramatic for safety applications. The main goal of this paper is to provide a method to synchronize beacons sending in a distributed manner so that all nodes proceed to their sending within a beacon session that takes place in one CCH interval (CCHI). Simulation results demonstrate the feasibility of the method and provide a high level of accuracy and efficiency compared with the standard.