# Autonomous Intersection Management by Using Reinforcement Learning
## 2 Related Work  
The idea of autonomous intersection management (AIM) was first introduced by [PERSON] et al. [10], who proposed a centralized method to model the intersection as tiles, and then reserve tiles for vehicles for passing. This approach introduces vehicle agents (VA) that control the vehicles and intersection agents (IA) residing at an intersection. When a vehicle approaches an intersection, the VA sends a reservation request to reserve tiles on its planned trajectory to the IA. As the IA receives the request, it first checks whether the needed tiles have been reserved. If reserved, IA rejects the request. If not, IA starts to simulate the trajectory of the requested vehicle across the intersection. During the internal simulation, if any requested tiles have already been reserved by another vehicle (which performed the internal simulation and was granted the tiles more quickly), IA ends the simulation and rejects the request. Otherwise, the reservation will be granted. Despite the outstanding research results on centralized resource reservation management, installing specialized infrastructure at each intersection may cause high costs. [PERSON] et al. [11] proposed the decentralized controller intersection management system. A decentralized intersection-management system gives the best waiting time compared to a centralized intersection-management system. [PERSON] et al. [12] suggest a distributed junction-management approach that gives emergency vehicles extra consideration. The suggested approach incorporates regulations based on the distributed intersection-management (DIM) protocol. [PERSON] et al. [13] discuss the reinforcement learning framework to enhance learning effectiveness and control performance for decision-making issues in automated vehicles. Three driving manoeuvres are involved: turning left, continuing straight, and turning right. The target missions are created by using the knowledge learned from the source driving task. [PERSON] et al. [14] present the trajectory planning model for minimizing the amount of time spent waiting at an intersection without traffic lights while ensuring safe driving. First, an information-gathering, organizing center called an intersection-management system gives acceptable priorities to all of the current cars and thereby determines their paths. Another way to plan trajectories for passing intersections is to use the idea of robot motion planning methods. Paths for each vehicle are first determined, and then the velocities for crossing the intersection efficiently and without collision are determined. [PERSON] et al. [15]proposed a heuristic model that enhances this administration of AIM. The effectiveness of this approach is shown by utilizing traffic recreations, with situations of various models, and measurements addressing the appearance time, CO2 outflow, and fuel utilization. [PERSON] et al. (2016) discuss the priority-based AIM. This framework can reenact complex street networks with traffic of independent vehicles under the administration of various traffic signal conventions at various crossing points. However, this approach takes a huge amount of waiting time. [PERSON] et al. discuss a priority-based intersection-management system ([PERSON] et al., 2018), which uses graph theory for the management. In ([PERSON] et al., 2018), [PERSON] et al. proposed a framework based on path-velocity decomposition. For determining the crossing sequence, the authors adopted the notion of priority to define the relative order among vehicles. Vehicles that want to pass the intersection must send a request to the intersection controller to gain priority. Those who do not have priorities are not allowed to enter the intersection. The authors introduced a priority assignment policy by simulating the trajectories of requesting vehicles and vehicles that have already been assigned priorities. If the vehicle could cross the intersection by using the maximum throttle command with the lowest priority, it would be assigned a priority and allowed to enter the intersection.