# Air Traffic Simulation Framework for Testing Automated Air Traffic Control Solutions +
## 7 Conclusions  
The air traffic simulation environment presented in this paper offers a versatile and modular framework for testing automated ATC solutions, with an emphasis on real-world applicability and data-driven validation. By integrating either real-time or recorded ADS-B data, the framework ensures realistic traffic scenarios, which are essential for the accurate assessment of automated control algorithms. Within the controlled sector, the impact of controller decisions is simulated and preserved, while surrounding traffic is continually updated from external sources to maintain contextual relevance. A central feature of the environment is its clearly defined and flexible interfaces, which enable seamless integration of external components. These include the following:  
* Traffic prediction for a selected area for flow management applications;
* Controller agents for algorithm development and validation;
* Implementing complex agents for modeling aircraft performance or traffic prediction. The simulation is implemented in MATLAB and offers an open-source structure, fostering customization and adaptability. Its modularity enables users to define their own control algorithms, measure performance indicators, and manipulate simulation complexity--such as by introducing randomized traffic or modeling human errors. The clarity and the control over the data flow in the simulation also enables flexible measurements of KPIs, which is suitable for many applications. The simulation is capable of forecasting air traffic within a timeframe specified by the user. While the prediction algorithm is initially presented in a simple, straightforward form, the simulation's modular architecture facilitates the implementation of upgrades that enhance the algorithmic sophistication. Additionally, the implementation of area-based segregation contributes to the refinement of prediction accuracy, while many of the proposed applications do not require precise forecasted aircraft positions but rather certain metrics of the sector, e.g., the expected traffic density for sectorization. Crucially, the simulation allows for the recording and replaying of traffic scenarios, which not only improves reproducibility but also eliminates dependency on live API availability. This facilitates robust testing under consistent conditions--an essential requirement for validation studies. The simulation output comprises a comprehensive traffic depiction under the control of the air traffic controller, alongside traffic metrics describing airspace complexity and the efficacy of control actions. These metrics include parameters such as the number of aircraft within a sector and instances of separation minima infringements. An example study was conducted to validate the workflow within the simulation environment using a sample controller algorithm. The results enabled the determination of an upper threshold for aircraft density within the airspace that allows for conflict-free operation. The complexity and effectiveness of conflict resolution are entirely dependent on the control agent, which is responsible for manipulating the traffic through the defined interface. The network layout--comprising waypoints as well as sector entry and exit points--defines how flights are guided through the airspace. In this architecture, flight plans are not directly known by the traffic simulation layer; instead, this information can be handled by the agents. For instance, if the controller agent is aware of an aircraft's flight plan and associated waypoints, it can issue instructions that consider the aircraft's intended trajectory and maintain network efficiency. If flight plans are known by the aircraft agent, it can generate requests for route shortening. Furthermore, the controller agent can represent more than one ATCO, as sectorization is implemented at the control agent level. From the perspective of the traffic simulation layer, it is irrelevant which specific controller issues a clearance.