# A Review of Counter-UAS Technologies for Cooperative Defensive Teams of Drones
## 7 Discussion  
For the purposes of this work, teams of mini drones have been considered as a reference subsystem of the hybrid CUS. This choice was due to several advantages in terms of mobility, coverage expansion, deployment flexibility, team coordination, automated decision-making, neutralization and scalability. The suitability of drone teams for CUS solutions was also confirmed by the analysis of the state-of-the-art research works in the fields of autonomous multi-agent systems and cooperative robotics. Moreover, some current international projects are developing both cooperative drone-based solutions for surveillance and situational awareness applications, as well as cooperative drone-based CUS.  
In regard to the sensing phase, this work argues that the proximal sensing capability of a team of mini drones is the main clear advantage over a static ground-based CUS. Drone-based video sensing systems are less affected by the optical occlusion problem, but there is the need for an accurate video stabilization to mitigate the blur effect due to the drone movement. Moreover, drone teams represent an ideal solution to balance the prosand cons of the different sensing technologies by means of a hybrid configuration of the team and data fusion techniques. The selection of the technologies that best complement each other is a useful activity in order to optimize the level of situational awareness with respect to the complexity and cost of the system, considering the specific requirements (i.e., range, accuracy, etc.) of the application.  
In regard to the neutralization phase, the use of mini drones can help in maximizing the effectiveness or efficiency of some neutralization techniques. For example, RF jamming may exploit the mobility of a single drone to reduce the power necessary to disturb the signal under attack, or the mobility of multiples drones, which can be used in a cooperative way to increase the power of the resulting jamming signal. Moreover, a drone team can be used directly as a neutralization technique, or small projectiles could be installed on mini drones, offering a similar solution to the nets case. In any case, for some techniques, it must be taken into account that the target pointing required by the neutralization integrated in the defensive drones can be a challenging issue.  
In regard to C2 systems, teams of drones are prone to automated decision-making capabilities according to the multilevel optimization principle. Based on the number of drones, a model based on \"cooperative autonomous systems\" can be applied, which is usually characterized by a collection of distinct decision-making entities for the decentralization of C2 operations.  
In the end, the implementation of a cooperative drone-based CUS raises several technological challenges, in terms of team coordination, team communication network and team simulation framework. All these challenges are also related to the reworking of some of the techniques of detection, classification, tracking and mitigation systems, in order to maximize performance and effectiveness by exploiting the underlying coordination network of the team.