Real-Time Analysis and Message Priority Assignment for TSN-CAN Gateway

As automobiles continue to develop in the direction of intelligence and networking, the requirements for in-vehicle network bandwidth and deterministic time delay continue to increase. However, existing in-vehicle network standard protocols such as Controller Area Network (CAN) cannot meet the increasing bandwidth needs of in-vehicle networks, and Time Sensitive Networking (TSN) has emerged a research hot-spot for next-generation in-vehicle network standards. The next-generation in-vehicle network is developing towards a domain network architecture with TSN as the backbone and other conventional buses as branches. In this architecture, the TSN-CAN gateway is an important component that handles the data communication between the TSN domain and CAN. Due to the large difference in transmission rates between TSN and CAN, the TSN-CAN heterogeneous gateway suffers from congestion resulting in unguaranteed real-time transmission of messages across the gateway. To address this issue, a high response ratio priority scheduling algorithm (HRRP) for TSN-CAN gateways based on worst-case response time analysis theory is proposed in this paper. The algorithm assigns forwarding priority to CAN messages based on the value of their response ratio, and the experimental demonstrate show that the method can significantly improve the schedulability and reduce latency, improving the real-time performance of the system.