On Scalable Network Communication for Infrastructure-Vehicle Collaborative Autonomous Driving

Network communication is crucial for Infrastructure-Vehicle Cooperative Autonomous Driving (IVCAD), which can help to improve both driving safety and efficiency. Existing IVCAD systems either use RoadSide Units (RSUs) deployed sparsely in critical locations to extend the on-board sensing, or use RSUs deployed densely in a limited area to provide both sensing and decision-making for vehicles. For both scenarios, the numbers of RSUs and vehicles are small, and the network communication solutions are based on the existing wireline and cellular network infrastructures and their extensions. However, it remains unknown whether these existing network communication solutions are scalable when the IVCAD system is deployed city-widely with hundreds of thousands of RSUs and millions of vehicles. In this paper, we analyze the network communication requirements for different types of IVCAD systems, and show that when the numbers of RSUs and vehicles in the system are large, using the existing solutions to support IVCAD can incur very high extra network communication facility cost. We further discuss how to use wireless mesh networks formed by RSUs themselves to solve the network communication problem without any deployment of extra network communication facilities. To enable the RSU network, we provide a network communication framework based on network coding and highlight some research directions.