A Comparison of Intelligent Signalized Intersection Controllers Under Mixed Traffic

Connected and automated vehicle (CAV) technology has progressed to the point where these vehicles are beginning to appear in traffic streams around the globe. As a result, there is a rising need for similar advances in the technology underlying traffic signal control systems. In this paper, we perform a quantitative and qualitative comparison of two state-of-the-art intelligent signal control systems; namely, the Hybrid Autonomous Intersection Management (H-AIM) [1] system and the Intelligent Intersection Control Algorithm (IICA) [2]. These systems use real-time sensors such as traffic cameras, vehicle-to-infrastructure communication, and real-time optimization and/or decision-making to maximize the efficiency of signalized intersections for CAVs as well as conventional vehicles. We describe the various assumptions under which these systems operate and present simulation results over a range of traffic scenarios and CAV penetration rates. Under the considered headways, IICA achieves the lowest travel times and highest throughput for CAV penetration rates up to around 95%.