High Gain Observer Design for DoS Attack Detection in CACC Platoon

In this paper, a high gain observer is designed to detect the DoS (Denial of Service) attack on autonomous connected vehicles. The Cooperative Adaptive Cruise Control (CACC) platoon model is chosen in this study due to a smaller headway between vehicles, where the data from sensors and transmitted through the wireless internet are easy to be attacked, especially for the wireless channel. To overcome the shortcomings of sliding mode observer in detecting the attacks, a high gain observer design approach is presented to derive the velocity and acceleration values which can be used to estimate the delay, and the performance is compared with sliding mode observer. The simulation results show that the high gain observer is more stable and can estimate the delay caused by the transmission in the wireless channel more accurate within the threshold. It concludes that when an attack occurs, the proposed detection mechanism can detect the attacks in real-time.