System for defense against a hostile unmanned aerial system

Abstract

To provide a system for defense against a H-UAS with improved functional performance and improved cost distribution between the system components, a system (100) for defense against a hostile unmanned aerial system (13) is proposed comprising at least one sensor unmanned aerial vehicle (14), wherein the sensor unmanned aerial vehicle (14) comprises a sensor system (16, 17) for detecting and / or tracking the hostile unmanned aerial system (13), and comprising at least one actuator unmanned aerial vehicle (15), wherein the actuator unmanned aerial vehicle (15) comprises an actuator system (18) configured to perform a defense measure against the hostile unmanned aerial system (13), wherein the sensor unmanned aerial vehicle (14) and the actuator unmanned aerial vehicle (15) are communicatively linked to one another to transmit data between the sensor unmanned aerial vehicle (14) and the actuator unmanned aerial vehicle (15).

Description

[0001] The invention relates to a system for defense against a hostile unmanned aerial system, a method for defending against a hostile unmanned aerial system using the system, a sensor unmanned aerial vehicle configured for use in the system and an actuator unmanned aerial vehicle configured for use in the system.

[0002] Unmanned Aerial Systems (UAS), in particular Small Unmanned Aerial Systems (sUAS), are increasingly endangering the public sector and there are as yet few effective countermeasures. The sUAS may also be referred to as Hostile Unmanned Aerial Systems (H-UAS). Common methods to defend against H-UAS are: Spoofing Jamming Hacking Ground-based network launchers Launching with e.g. rifles Partially or fully automated interceptor drones, counter-UAS, in short: C-UAS.

[0003] Some of these methods have a very limited range. Classical ballistic methods, typically used in military environments are not possible in a civilian environment, and it has also been shown that several hundred rounds are required to engage even a stationary sUAS.

[0004] Known C-UAS are relatively large and heavy making them not agile enough to track H-UAS. H-UAS can be very fast (up to approx. 40 m / s) and agile, especially if they are remote-controlled with the help of a camera. In this case, they are referred to as a First-Person-View-UAS (FPV-UAS). Here, the H-UAS is controlled from the perspective of the remote-controlled model as if from the viewpoint of a driver / pilot, thus creating the feeling that you are not flying in "third person", but in first person view.

[0005] The size and weight of the C-UAS are due to the fact that the C-UAS must be equipped with suitable sensors and actuators in order to track an H-UAS. Depending on the application, it should be possible to transport an H-UAS suspended in a C-UAS net to a safe location after a successful launch. This means that the motors, the frame and the energy reserves of the C-UAS must be dimensioned in such a way that the additional weight of an H-UAS can also be supported.

[0006] There is also a desire to use the most powerful sensor technology possible (multi-sensor technology) in order to detect, localize and track the H-UAS as early as possible and over long distances.

[0007] It is an object of the invention to provide a system for defense against a H-UAS with improved functional performance and improved cost distribution between the system components.

[0008] The object of the invention is solved by a system for defense against a hostile unmanned aerial system comprising at least one sensor unmanned aerial vehicle, wherein the sensor unmanned aerial vehicle comprises a sensor system for detecting and / or tracking the hostile unmanned aerial system, and comprising at least one actuator unmanned aerial vehicle, wherein the actuator unmanned aerial vehicle comprises an actuator system configured to perform a defense measure against the hostile unmanned aerial system, wherein the sensor unmanned aerial vehicle and the actuator unmanned aerial vehicle are communicatively linked to one another to transmit data between the sensor unmanned aerial vehicle and the actuator unmanned aerial vehicle.

[0009] In the following the sensor unmanned aerial vehicle may be also referred to as S-UAV, the actuator unmanned aerial vehicle may be referred to as A-UAV and the hostile unmanned aerial vehicle may be referred to as H-UAS.

[0010] The S-UAV and the A-UAV may in particular be drones.

[0011] The system advantageously allows to separate the function of detecting the H-UAS and eventually performing a defense measure against the H-UAS in two different devices. For this, the S-UAV is provided which has the sensor system which may detect the H-UAS. The detection here may comprise at least the determination that the H-UAS is present and where it is positioned. Furthermore, the detection may comprise the tracking of the H-UAS. To effectively perform these functions, the sensor system may be provided with a plurality of different sensors which will be described later in detail. Furthermore, the A-UAV is provided having the actuator system which ultimately performs the defense or attack measure. The aforementioned functions have been implemented in a single UAV or UAS in conventional systems making them too heavy for agile maneuvers and too expensive in case of loss or damage of the UAV. To solve this problem, the components that are usually included in a UAV are distributed over at least two separate devices, namely the S-UAV and the A-UAV.

[0012] In particular, the function of detecting the H-UAS in the long range or the function of coordination of one or a multiple of A-UAVs is exclusively performed by the S-UAV and not by the A-UAV. For short-range tracking of the H-UAS the A-UAV can also be equipped with sensors for performing the defense or attack measure. However, the initial detection and tracking of the H-UAS is performed by the S-UAV. Thus, the S-AUV is equipped with more advanced sensor technology compared to the A-UAV. In turn, the function of performing the defense or attack measure is exclusively performed by the A-UAV. Thus, preferably, the S-UAV does not comprise means for performing defense measures against the H-UAS.

[0013] In other words, the technical problem is solved by an appropriate distribution of functionalities resulting in an appropriate distribution of sensors and actuators. Sensors and actuators, which are usually integrated in a C-UAS, are divided into separate flight platforms, the S-UAV and the A-UAV, which may interact with each other cooperatively via a wireless network or data link. They thus form an airborne sensor-actuator network.

[0014] Via the communicative link between the S-UAV and the A-UAV different data may be transmitted, such as sensor data, control data, monitoring or status data or positioning data.

[0015] The communicative link between the S-UAV and the A-UAV may be unidirectional or bi-directional. For example, data may only be transmitted from the S-UAV to the one or more A-UAV but not in the opposite direction. However, also bi-directional communication is possible. In particular, the A-UAV may transmit position data or status data to the S-UAV.

[0016] The S-UAV may be considered as a control center or command center of the system. Thus, the S-UAV may comprise corresponding control hardware and software. In particular, the entire maneuver of defense against the H-UAS is controlled by the S-UAV. For this, the S-UAV collects sensor data by means of the sensor system and plans the maneuver against the H-UAS based on the sensor data. For this, the S-UAV transmits control and positioning data generated based on the sensor data and optionally further data, in particular continuously, to the A-UAV and instructs the A-UAV to follow the H-UAS based on the transmitted information. The information stream may in particular comprise the present position of the H-UAS, the present position of the A-UAS, a prediction of the future trajectory of the H-UAS and control information to bring the A-UAS in the position that they have the H-UAS in their own limited sensor range, which is called the rendezvous distance. Thus, the A-UAV may effectively track the H-UAS since it is provided with respective position data before approaching the rendezvous distance or when the H-UAS disappeared out of sight of the A-UAS sensor range. In other words, the S-UAV may guide the A-UAS towards the H-UAS, that is providing control data for the movement of the A-UAS. The control data may for example comprise target coordinates and an approach strategy for the A-UAV so that the A-UAV may move towards the target coordinates, i.e. to the rendezvous point or directly in a perfect attack or defense position relative to the H-UAV.

[0017] In particular, the S-UAV and the A-UAV may use a joint coordinate system wherein position data and / or control data are represented using the joint coordinate system. The coordinate origin may in particular be the S-UAV or a reference point in the S-UAV. Thus, the coordinate system may move together with the S-UAV providing an reference frame independent of any stationary coordinate systems. Therefore, the system may advantageously be employed in GNSS denied areas or in cases where no communicative connection is present to a base station or to other networks.

[0018] Preferably, in approaching the H-UAS the A-UAS follow the S-AUS in a predetermined pattern and / or a predetermined radius, for example between 5 m and 50 m. Once the S-UAS detects a H-AUS, the S-UAS instructs the A-UAS to target the H-UAS and provides position data of the H-UAS to the A-UAS.

[0019] In particular, the system may be employed independent of any further control station or control device. That means, that a control unit of the system, in particular the control hardware and software of the S-UAV, may be configured such that a strategy of specific maneuver against a H-UAS may be planned beforehand and may be executed by the system autonomously. This allows the system to be used in remote areas where no communication is possible with a base station.

[0020] Preferably, the system comprises more than one sensor unmanned aerial vehicle and / or more than one actuator unmanned aerial vehicle. For example, the system may comprise one S-UAV and two or more A-UAV. In this case, the S-UAV communicates with and controls the two or more A-UAV. The two or more A-UAV may be employed to either target the same H-UAS or different H-UAS. In particular, each A-UAV may target one dedicated H-UAS. Furthermore, several S-UAV may be provided together with a single or several A-UAV. For example, with three A-UAV one H-UAS may be easily targeted.

[0021] If several sensor unmanned aerial vehicles and / or several actuator unmanned aerial vehicles are provided different sensor functionalities may be distributed over several S-UAV and actuator functionalities over several A-UAV.

[0022] Preferably, all UAS of the system, that is all S-UAV and A-UAV, are interconnected with each of the other UAS of the system. Any of the communication topologies known from computer networks, e.g. mesh, star, tree, ring, point-to-point, daisy chain may be employed, whereas a star or mesh topology would be advantageously be employed. E.g., there may only be a communicative link between a S-UAV and a multiple of A-UAV in a star-shaped topology without direct communicative link between the A-UAV.

[0023] The A-UAV may also have communicative links between each other. For example, the A-UAV may exchange their current positions and / or tracking and approach strategies in order to move or position each other relative to one in other in a certain pattern. In this case the A-UAS have a greater autonomy from the control computer on the S-UAS.

[0024] Thus the S-UAS and A-UAS may also be regarded as an airborne intelligent multi-agent system. This may be the case when the A-UAV and S-UAS approach in a specific formation and as soon as the H-UAS is within the sensor view of the A-UAS they attack or defend the system in a coordinated manner independent from the S-UAV. The S-UAV in this case merely initially instructs the A-UAV to perform the maneuver once the A-UAV detects the H-UAS and the A-UAV receive the respective control commands from the S-UAV. Then the A-UAV begin their maneuver and once the H-UAS is within the detection range of the sensor devices of the A-UAV they are able to perform the maneuver without further instructions and / or sensor data from the S-UAV. This may be particularly advantageous in remote areas.

[0025] Preferably, the actuator unmanned aerial vehicle is configured to communicate its position, in particular GNSS (Global Navigation Satellite System) position, and / or its speed, in particular its vectorial speed, to the sensor unmanned aerial vehicle and / or wherein the sensor unmanned aerial vehicle is configured to detect a location and / or speed, in particular the vectorial speed, of the actuator unmanned aerial vehicle. In this way, the S-UAV may coordinate the movement of the A-UAV and may decide whether the A-UAV is in a position that may allow the A-UAV to target the H-UAS and perform the defense measure. The S-UAV may obtain the position and / or speed of the A-UAV by either directly receiving the position and / or speed data from the A-UAV or by using the sensor system to detect the position and / or speed of the UAS. Thus, the S-UAV is also able to determine the respective position and the respective vectorial speed of the A-UAV with its own sensor technology in GNSS denied areas. In the event of a GNSS failure, the S-UAV can also guide the A-UAV using relative position information.

[0026] Preferably, the actuator unmanned aerial vehicle has a sensor device for detecting a position of the hostile unmanned aerial system, wherein a detection range and / or field of view of the sensor system of the sensor unmanned aerial vehicle is greater than that of the sensor device of the actuator unmanned aerial vehicle, wherein preferably the detection range and / or field of view of the sensor device is between 5% and 20%, more preferably between 7% and 15%, especially preferably between 9% and 11%, of the detection range of the sensor system. In other words, a performance of the sensor system of the S-UAV is significantly larger than that of the sensor device of the A-UAV. This allows the A-UAV to be configured with a lower weight or with an improved higher thrust-to-weight-ratio which advantageously increases is agility when performing defense measures and in particular when following the H-UAS. Also there may be more powerful equipment comprising software and hardware with more weight and power consumption for detection, classification and tracking of an H-UAS mounted on the S-UAS compared to a lean solution realized on a A-UAS.

[0027] In contrast to ground-based sensor technology, the sensor system on the S-UAV may only have a range of 100 m to 1 km. More is not necessary, as this is usually enough for an S-UAV to follow an H-UAS. During the defense measure, such as a capture process, the problem is not so much the basic speed as the agility of a C-UAS to be able to follow or anticipate fast turning maneuvers or changes of direction. Thus, this functionality is outsourced to the A-UAV. The A-UAV are therefore designed to be very fast and, above all, agile. Thus, the thrust-to-weight ratio of the A-UAV should be approximately one order of magnitude better than the thrust-to-weight ratio of a S-UAS . The S-UAV thus corresponds to an airborne control center.

[0028] A high-performance communication network between the S-UAV and the A-UAV is required. The response times should be significantly less than 100 ms.

[0029] Preferably, in particular exclusively, the sensor unmanned aerial vehicle is configured for communication with a base station, preferably a ground base station. Thus, the A-UAV exclusively communicate with the S-UAV and / or with the A-UAV. The S-UAV may be controlled and / or monitored form the base station. However, the S-UAV may be set up such that is operated independently from a base station.

[0030] Preferably, the sensor unmanned aerial vehicle and the actuator unmanned aerial vehicle are configured for communication over a mobile network, in particular a low-latency network like 5G. One form of implementation could be a 5th generation mobile radio network, for example, in which the S-UAV also carries a "flying base station". Other wireless solutions are also possible.

[0031] Preferably, the A-UAV have a quadrocopter, hexacopter or octocopter as a carrier base. Furthermore, the A-UAV may be based on a fixed wing UAV.

[0032] Preferably, the sensor system of the sensor unmanned aerial vehicle comprises one or more of a RADAR and / or LIDAR sensor device, one or more camera devices, one or more opto-electric infrared sensor device, a broadband radio spectrum and / or communication analyzer, a radio direction finder and / or an acoustic sensor device. Thus, different sensor technologies may be combined in one S-UAV advantageously improving its performance. It is also conceivable that different sensor functionalities are distributed over several S-UAV. Also the A-UAV may comprise one or more of the aforementioned sensor technologies, however, the sensor may be limited in terms of performance to limit the weight and improve the thrust-to-weight ratio of the A-UAV.

[0033] Preferably, the defense measure is catching, destroying and / or causing a crash of the hostile unmanned aerial system. To perform these defense measures, the A-UAV comprises respective means.

[0034] Preferably, the actuator system comprises a net for catching the hostile unmanned aerial system and / or means for destroying the hostile unmanned aerial system, such as a shooting device for shooting the H-UAS. There might furthermore be provided a net shooting device for shooting the net towards the H-UAS such that the H-UAS will either crash or the net may be connected to the A-UAV such that the A-UAV may capture the A-UAV and transport the H-UAS to a predetermined location. The nets may have a size with a side length between 4 m and 7m. The nets may have a square or rectangular shape. The A-UAS may also be equipped with a jamming device or a spoofing device to suppress any communication of the H-UAS or to take-over control of the H-UAS.

[0035] Both or only one of the S-UAV and the A-UAV can be equipped with suitable sensors to detect whether there is an H-UAS in the net. If this sensor detects that an H-UAS has been captured, the net and H-UAS may be ejected so that the H-UAS crashed together with the net.

[0036] Preferably, the system comprises several, at least two three, four or more, actuator unmanned aerial vehicles which are configured to span a net attached to each of the actuator unmanned aerial vehicle such that the net span or hung over a predetermined, in particular vertical, area. For this, the A-UAV may be controlled, in particular by the S-UAV, to move or be stationarily positioned in a predetermined formation, in particular a straight line, such that the net is span along the A-UAV of the formation. It is also possible, that several nets are span according to the described principle. The nets of this embodiment may be larger than nets used for shooting towards the H-UAS. In particular, the net or nets may have a side length between about 20 m to 50 m. The nets may have a square or rectangular shape.

[0037] In this scenario, it is typically assumed that an H-UAS is flying in a straight line towards an object or a crowd of people that requires protection. The speed can be relatively high, e.g. > 30 m / s. This scenario occurs if a route has been programmed into the H-UAS in advance, i.e. the H-UAS flies according to so-called waypoints, for example.

[0038] The net can also be weighted down with concentrated or distributed weights (e.g. rods) to prevent it from being blown away by the wind.

[0039] Furthermore, the net may be configured such that it is not visible to the naked eye and such that even a high-resolution camera can only detect the net with difficulty. This may be achieved by choosing a suitable mesh sizing and thread width. The mesh size is typically 20 cm x 20 cm to 40 cm x 40 cm and the individual net threads have a width of approx. 0.1 mm - 0.2 mm.

[0040] Suspensions means, such as suspension ropes, may be provided to attach the net at a certain distance to the A-UAV. The suspension ropes on which the net hangs may have a length of at least 10 m and more, so that the A-UAV do not come into the field of view of a camera of an H-UAS.

[0041] Due to the size of the net, it is hardly possible to move it quickly from one place to another. The transfer speed may be approximately 1 m / s. This means that this type of setup is usually not suitable for tracking an H-UAS. Thus, the net may be placed in a preprogrammed path of an approaching H-UAS.

[0042] It is also possible to position several of these nets one behind the other, so that not only a small H-UAS but also larger H-UAS can be intercepted, where there is a risk that the large propellers would cut through a net.

[0043] It is also possible that several nets are positioned next to each other and on top of each other by the A-UAV in order to create an even larger protective or effective area.

[0044] The net or nets can also be reinforced with additional cords or ropes to prevent the net from being cut by larger H-UAS. It is also advantageous if the nets are equipped with one or more parachutes to increase the braking effect in the event of a captured H-UAS.

[0045] It is also possible to set up one or more nets with several A-UAV horizontally. In this way open stadiums, for example, can also be protected against the entering of H-UAS.

[0046] In the case of particularly fast H-UAS, where the flight path cannot be precisely predetermined, several A-UAV can also form a row or a similar pattern where the A-UAV cover a certain area in order to increase the probability of the defense measure of the A-UAV being effective or successful.

[0047] In a further embodiment, the one or more A-UAV may be controlled such that the H-UAS is forced towards the one or more nets.

[0048] This scenario, which may also be referred to as the hammer-anvil-principle, is based on the assumption that an H-UAS is flown professionally, e.g. via FPV. If a A-UAV appears in the drone controller's video image, the controller must react and initiate evasive maneuvers. In this case, it is assumed that the human senses are quickly "oversaturated". The A-UAV will automatically attempt to drive the H-UAS towards the large net, so that if the drone pilot is inattentive, the H-UAS will fly into the large net that may not be visible. The prerequisite for this is that the A-UAV is aware of the position of the safety net or safety nets at all times, so that it does not become entangled in them itself.

[0049] In all cases where a net is span by several A-UAS the S-UAS may detect the position and orientation of the net by means of the sensor system. The position and / or orientation data may be communicated to the A-UAS.

[0050] In the EU Drone Regulation 2021, Unmanned Aerial Vehicles (UAV) are divided into different categories C0 - C6: C0: Maximum take-off weight (MTOW) of the UAV is less than 250g C1: MTOW < 900 grams or kinetic energy < 80 joules C2: MTOW < 4 kg C3 / C4: MTOW < 25 kg C5 / C6: Unmanned Aerial Systems (UAV + remote control) correspond to UAS of class C3, but which are no longer subject to the automatic altitude limitation due to special modifications and requirements and also do not require a system for automatic flight restriction monitoring.

[0051] The present invention preferably aims at intercepting all UAVs listed above. Only in the case of categories C0 to C2 it is the aim to transport the intercepted UAV in the net. In the other categories, the connection to the net is preferably disconnected for safety reasons before the net is thrown.

[0052] In general, it is also possible that several of the aforementioned systems may be provided which are employed simultaneously. For example several of the system may be arranged hierarchically or next to each other to perform a maneuver. For example, the systems may take turn during a maneuver to increase the flight time.

[0053] An area that may be monitored by the system may have a size of for example 1 km x 1km.

[0054] The technical problem is furthermore solved by a method for defending against a hostile unmanned aerial system using the system with the aforementioned features, comprising the following steps: Detecting the hostile unmanned aerial system by means of the sensor system of the sensor unmanned aerial vehicle, Determining a position of the hostile unmanned aerial system and transmit position data of the hostile unmanned aerial system to the actuator unmanned aerial vehicle, Moving the actuator unmanned aerial vehicle towards the hostile unmanned aerial system based on the position data, and Performing the attack or defense measure against the hostile unmanned aerial system by means of the actuator unmanned aerial vehicle.

[0055] Preferably, the sensor unmanned aerial vehicle is tracking the movement of the hostile unmanned aerial system. To achieve this, the S-UAV may follow the H-UAS such that the S-UAV is within the detection range of the sensor system of the S-UAV at all times. For this, a moderate agility of the S-UAV is sufficient. The one or more A-UAS may follow the S-UAV, for example while always staying within a predetermined distance to the S-UAV. Thus, the at least one S-UAV and the A-UAV may fly in a formation. The A-UAV may leave the formation to track the H-UAS and ultimately perform the defense or attack measure once instructed by the S-UAV. In other words, the A-UAV may swarm out once the S-UAV determined that a H-UAS is present. The S-UAV may remain at an distant standby position or may follow an approximate trajectory of the H-UAS such that the H-UAS is within the detection range of the H-UAS and such that a communication with the A-UAV is still possible. This scenario may also be referred to as a high-dynamic scenario.

[0056] Preferably, the actuator unmanned aerial vehicle has a sensor device for detecting a position of the hostile unmanned aerial system, wherein a detection range and / or field of view of the sensor system of the sensor unmanned aerial vehicle is greater than that of the sensor device of the actuator unmanned aerial vehicle. By means of the sensor system the unmanned aerial vehicle or a group of unmanned aerial vehicles may act as an agent or as an agent system which may perform certain tasks independent from the S-UAS. The A-UAS may in particular form an agent system as is known from automation technology.

[0057] Preferably, a plurality of actuator unmanned aerial vehicles are provided, wherein the actuator unmanned aerial vehicle are each connected to a net and wherein the actuator unmanned aerial vehicle are moved into a formation such that the net is span over a predetermined, in particular vertical, area. This scenario may also be referred to as a stationary scenario.

[0058] In addition the technical problem is solved by a sensor unmanned aerial vehicle configured for use in the system with the aforementioned features.

[0059] Also the technical problem is solved by a actuator unmanned aerial vehicle configured for use in the system with the aforementioned features.

[0060] The invention is explained in more detail below with reference to exemplary embodiments. It shows in Fig. 1a C-UAS of the prior art, Fig. 2a C-UAS of the prior art performing a defense measure, Fig. 3a system for defense against a H-UAS according to the invention, Fig. 4a system for defense against a H-UAS according to a first embodiment, Fig. 5a system for defense against a H-UAS according to a second embodiment, Fig. 6a system for defense against a H-UAS according to a third embodiment, Fig. 7a system for defense against a H-UAS according to a fourth embodiment, and Fig. 8a system for defense against a H-UAS according to a fifth embodiment.

[0061] Figure 1 shows a C-UAS 100' from the prior art. The C-UAS 100' comprises sensor devices 10', 10" in the form of a RADAR unit and a camera which is gimballed to the C-UAS. Furthermore, the C-UAS 100' comprises two net guns 11' for shooting a net 12'towards a target.

[0062] The process of shooting the net 12' towards a H-UAS 13 as a target is shown in Figure 2. Due to the number, size and weight of the components of the C-UAS 100', such as the sensor devices 10', 10" and the net guns 11', the C-UAS 100' is not agile enough to track especially fast and agile H-UAS. Furthermore, damages to the C-UAS 100' or even a crash result in high loss of costs.

[0063] To solve this problem, the system 100 according to the invention as shown in Figure 3 distributes the components of a common C-UAS 100' as shown in Figure 3 on the left is distributed to two separate UAS 14, 15 as shown in the middle and on the right in Figure 3. A first of the two UAS is the S-UAV comprising the sensor system. The sensor system comprises a RADAR unit 16 and a camera 17 for monitoring an area for H-UAS 13 entering the area.

[0064] The other one of the two UAS is the A-UAV 15 which comprises an actuator system. The actuator system comprises a LIDAR and four net guns. Since the components of the system are distributed over more than one device, the flight dynamics of the UAS, in particular the A-UAV 15, can be improved.

[0065] Figure 4 shows a further embodiment in which two A-UAV 15 are assigned to one S-UAV 14. The two A-UAV 15 may be employed to target the same H-UAS 13 or the A-UAV-15 may target different H-UAS 13. Figure 4 shows a high-dynamic scenario in which the A-UAV 15 swarm out to follow and target a very fast and agile H-UAS 13. The movement of the H-UAS is controlled or conducted by the S-UAS 14 which has a communicative link 19 to each of the A-UAV 15. The arrows in Figure 4 depict further communicative links which are also present between the A-UAV 15-

[0066] Figure 5 shows a further embodiment of a high-dynamic scenario similar to that shown in Figure 4. In contrast to the embodiment of Figure 4, the A-UAV 15 are here configured as fixed wing UAS each having a single net ejector 18.

[0067] Figure 6 shows a further embodiment of the system 100 wherein three A-UAV 15 are moved cooperatively. The three A-UAV 15 are spanning a net 20 which is used to catch or intercept a H-UAS 13. For this, there the A-UAV 15 are communicatively linked with one another to coordinate the formation of the A-UAV 15 such that the net 20 is held in the desired position. In a minimal configuration one of the A-UAVs can also be replaced by the S-UAS. In this case the S-UAS still has the role of a command and control center but is additionally equipped with means to carry the net with the risk that in the case that the interception process does not go as planned, the UAS may be affected.

[0068] In Figure 7, a further embodiment is shown in which several A-UAV 15 form rows, in this case two rows with three A-UAV 15 each. The A-UAV 15 are arranged such that they cover a certain area in which they may catch the H-UAS 13. This area is greater than that of the single A-UAV 15 so that the probability of catching the H-UAS is increased. This is in particular advantageous for small and agile H-UAS which trajectory may not be assessed beforehand.

[0069] In the embodiment shown in Figure 8 a first group of A-UAV 15 carry a net 20 in a similar fashion as shown in Figure 6. The net 20 may be held stationary or may move. A further A-UAV is employed to push or herd the H-UAS towards 13 towards the net 20. It is assumed that in this case the human senses of the operator of the H-UAS 13 are quickly "oversaturated". The C- A-UAV will automatically try to drive the H-UAS towards the large net, so that if the operator is inattentive, the H-UAS will fly into the large net that is preferably not visible.List of reference signs

[0070] 100,100'systems 10', 10"sensor devices of a sensor system 11'actuator system 12'net 13H-UAS 14S-UAV 15A-UAV 16RADAR unit 17camera 18net ejectors 19communicative link 20net

Claims

1. System (100) for defense against a hostile unmanned aerial system (13) comprising at least one sensor unmanned aerial vehicle (14), wherein the sensor unmanned aerial vehicle (14) comprises a sensor system (16, 17) for detecting and / or tracking the hostile unmanned aerial system (13), and comprising at least one actuator unmanned aerial vehicle (15), wherein the actuator unmanned aerial vehicle (15) comprises an actuator system (18) configured to perform a defense measure against the hostile unmanned aerial system (13), wherein the sensor unmanned aerial vehicle (14) and the actuator unmanned aerial vehicle (15) are communicatively linked to one another to transmit data between the sensor unmanned aerial vehicle (14) and the actuator unmanned aerial vehicle (15).

2. System (100) of claim 1, comprising more than one sensor unmanned aerial vehicle (14) and / or more than one actuator unmanned aerial vehicle (15).

3. System (100) of one of the preceding claim, wherein the actuator unmanned aerial vehicle (15) is configured to communicate its position, in particular GNSS position, and / or its speed to the sensor unmanned aerial vehicle (14) and / or wherein the sensor unmanned aerial vehicle (14) is configured to detect a location and / or speed of the actuator unmanned aerial vehicle (15).

4. System (100) of one of the preceding claims, wherein the actuator unmanned aerial vehicle (15) has a sensor device for detecting a position of the hostile unmanned aerial system (13), wherein a detection range and / or field of view of the sensor system (16, 17) of the sensor unmanned aerial vehicle (14) is greater than that of the sensor device of the actuator unmanned aerial vehicle (15), wherein preferably the detection range and / or field of view of the sensor device is between 5% and 20%, more preferably between 7% and 15%, especially preferably between 9% and 11%, of the detection range of the sensor system (16, 17).

5. System (100) of one of the preceding claims, wherein, in particular exclusively, the sensor unmanned aerial vehicle (14) is configured for communication with a base station, preferably a ground base station.

6. System (100) of one of the preceding claim, wherein the sensor unmanned aerial vehicle (14) and the actuator unmanned aerial vehicle (15) are configured for communication over a mobile network, in particular 5G.

7. System (100) of one of the preceding claims, wherein the sensor system (16, 17) of the sensor unmanned aerial vehicle (14) comprises one or more of a RADAR and / or LIDAR sensor device (16), a camera device (17), an opto-electric infrared sensor device, a spectrum analyzer, a communication analyzer, a radio direction finder and / or an acoustic sensor device.

8. System (100) of one of the preceding claims, wherein the defense measure is catching, destroying and / or causing a crash of the hostile unmanned aerial system (13).

9. System (100) of one of the preceding claim, wherein the actuator system comprises at least one net (20) for catching the hostile unmanned aerial system (13) and / or means for destroying the hostile unmanned aerial system (13).

10. System (100) of one of the preceding claims, wherein the system (100) comprises several, at least two three, four or more, actuator unmanned aerial vehicles (15) which are configured to span a net (20) attached to each of the actuator unmanned aerial vehicles (15) such that the net (20) is span over a predetermined, in particular vertical, area.

11. Method for defending against a hostile unmanned aerial system (13) using the system (100) of one of the preceding claims, comprising the following steps: - Detecting the hostile unmanned aerial system (13) by means of the sensor system (16, 17) of the sensor unmanned aerial vehicle (14), - Determining a position of the hostile unmanned aerial system (13) and transmit position data of the hostile unmanned aerial system (13) to the actuator unmanned aerial vehicle (15), - Moving the actuator unmanned aerial vehicle (15) towards the hostile unmanned aerial system (13) based on the position data, and - Performing the defense and attack measure against the hostile unmanned aerial system (13) by means of the actuator unmanned aerial vehicle (15).

12. Method of claim 11, wherein the sensor unmanned aerial vehicle (14) is tracking the movement of the hostile unmanned aerial system (13).

13. Method of claim 11, wherein a plurality of actuator unmanned aerial vehicles (15) are provided, wherein the actuator unmanned aerial vehicles (15) are each connected to a net (20) and wherein the actuator unmanned aerial vehicles (15) are moved into a formation such that the net (20) is span over a predetermined, in particular vertical, area.

14. Sensor unmanned aerial vehicle (14) configured for use in the system (100) of one of claims 1 to 10.

15. Actuator unmanned aerial vehicle (15) configured for use in the system (100) of one of claims 1 to 10.

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