EP4381624A1

EP4381624A1 - Frequency band assignment in a swarm of aerial vehicles

Info

Publication number: EP4381624A1
Application number: EP21754976.5A
Authority: EP
Inventors: Wojciech POTENTAS; Branko DJORDJEVIC; Konrad Liedtke
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2024-06-12
Also published as: WO2023011709A1

Abstract

A technique of controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, is provided. The multi-sector antenna system is mounted on a first aerial vehicle (100) and comprises one antenna per sector. The first aerial vehicle (100) moves within a swarm of aerial vehicles (100). As to a method aspect, a trajectory (1402) of the first aerial vehicle (100) relative to other aerial vehicles (100) within the swarm is determined. An indication of the trajectory (1402) is transmitted to another aerial vehicle (100) within the swarm. An assignment of frequency bands to the antennas of the multi-sector antenna system mounted on the first aerial vehicle (100) is substituted depending on the trajectory (1402) while the first aerial vehicle (100) moves on the trajectory (1402). Each antenna of the multi-sector antenna system is assigned at least one frequency band.

Description

FREQUENCY BAND ASSIGNMENT IN A SWARM OF AERIAL VEHICLES

Technical Field

The present disclosure relates to a technique for frequency band assignments of aerial vehicles moving within a swarm of aerial vehicles in two-dimensional and/or three- dimensional constellations.

Background

Conventional radio access networks (RANs), e.g., an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) according to the Long Term Evolution (LTE) standard of the Third Generation Partnership Project (3GPP) comprise radio base stations (RBSs) standing on masts. One frequency band can conventionally be used to provide coverage over large areas when precisely defining the placement of the masts and associated antennas powers. Occasionally, a different frequency band is planned to be used in a particular place to avoid interferences that cannot be avoided by defining suitable antenna powers or spatial ranges.

According to the document WO 2021/098972, a single RBS drone (as an example of an aerial vehicle) is used for adding spotty coverage over a small area and for providing capacity to the RAN for firefighters (or other emergency services) where disasters occurred, or where it is hard to provide internet connection by a land (i.e., terrestrial) network. Fig. 5 shows an example of an RBS drone 504-1 starting from a terrestrial base 502 and performing a path 506. In the example of Fig. 5, five different closed loop paths 506-1, 506-2, 506-3, 506-4 and 506-5 are shown with predetermined positions of the RBS drone 504-1, 504-2, 504-3, 504-4 and 504-5 on the respective path shown as small circles.

In WO 2021/098972, a plurality of RBS drones serves a limited geographical area providing RAN coverage. As shown in Fig. 6, the RBS drones 504-1, 504-2, 504-3, 504-4, 504-5, 504- 6, 504-7 and 504-8 circularly switch positions 506-1, 506-2, 506-3, 506-4, 506-5, 506-6 and 506-7 (e.g., following a Daisy chain-like pattern) whenever a new RBS drone 504-8 starts from the terrestrial base 502, the last RBS drone 504-1 lands and intermediate RBS drones 504-2, 504-3, 504-4, 504-5, 504-6 and 504-7 perform handovers of user equipments (UEs) 704-1, 704-2 and 704-3 in their positions 506-1, 506-2, 506-3, 506-4, 506-5, 506-6 and 506- 7 and succeed the respective predecessor RBS drone 504-1, 504-2, 504-3, 504-4, 504-5, 504-6 and 504-7 in service, as also shown in Fig. 7, in which the coverage area 702-1, 702- 2 and 702-3 of the three RBS drones 504-1, 504-2 and 504-3, respectively, is shown. Existing terrestrial deployments of a RAN are vulnerable to, e.g., natural, disasters. Moreover, terrestrial RAN coverage is not guaranteed, or may not exist, in some geographical areas such as in mountainous regions or deserts. When a RBS is mounted on a flying or aerial vehicle, it may fail to provide service due to technical problems such as low battery and/or mechanical faults in mid-air, e.g., due to bird-strike or weather phenomena such as lightning strike. Another RBS mounted on another flying or aerial vehicle may be deployed to recover the RAN coverage.

However, when deploying more than one RBS drone or RBSs mounted on a flying vehicle, interferences of transmissions by the RBS drones or RBSs mounted on the flying vehicles conventionally lead to a deterioration of the RAN coverage as compared to a single RBS drone or a single RBS mounted on a flying vehicle serving UEs in a geographical area.

Summary

Accordingly, there is a need for a techniques that safeguards aerial vehicles within a swarm of aerial vehicles against interferences from other aerial vehicles within the swarm. Alternatively or in addition, there is a need for a technique that avoids interferences between aerial vehicles in relative movement to each other.

As to a first method aspect, a method of controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network (RAN) is provided. The multi-sector antenna system is mounted on a first aerial vehicle. The multi-sector antenna system comprises one antenna per sector, and the first aerial vehicle moves within a swarm of aerial vehicles. Each aerial vehicle in the swarm comprises a multi-sector antenna system. The method comprises or initiates a step of determining a trajectory of the first aerial vehicle relative to other aerial vehicles within the swarm. The method further comprises or initiates a step of transmitting an indication of the determined trajectory to at least one other aerial vehicle within the swarm. The method still further comprises or initiates as step of substituting an assignment of frequency bands to the antennas of the multi-sector antenna system mounted on a first aerial vehicle depending on the determined trajectory while the first aerial vehicle moves on the determined trajectory. Each antenna of the multi-sector antenna system mounted on a first aerial vehicle is assigned at least one frequency band.

The method according to the first method aspect may be performed at the first aerial vehicle. As to a second method aspect, a method of controlling a plurality of frequency bands of a multi-sector antenna system of a RAN is provided. The multi-sector antenna system is mounted on any one aerial vehicle within a swarm of aerial vehicles. The multi-sector antenna system of each aerial vehicle comprises one antenna per sector, and each aerial vehicle moves within the swarm of aerial vehicles. The method comprises or initiates a step of determining a trajectory of at least one aerial vehicle relative to at least one other aerial vehicle within the swarm and/or determining an assignment of frequency bands to the antennas of the multi-sector antenna system of at least one aerial vehicle within the swarm. The method further comprises or initiates a step of transmitting the determined trajectory of the at least one aerial vehicle and/or the determined assignment of the frequency bands of the at least one aerial vehicle to at least one aerial vehicle within the swarm of aerial vehicles.

The method according to the second method aspect may be performed by a controller of the swarm of aerial vehicles.

The swarm of aerial vehicles may be configured to provide RAN coverage to one or more radio devices over a geographic area and/or a terrestrial area.

The technique may be applied in the context of 3GPP New Radio (NR).

Any radio device may be a user equipment (UE), e.g., according to a 3GPP specification.

The first and/or any other aerial vehicle of the swarm and a base station of the RAN may be wirelessly connected through a backhaul comprising, e.g., an SI and/or an Sl-U interface. Alternatively or in addition, the first and/or any other aerial vehicle of the swarm may be wirelessly connected among each other through an inter-aerial vehicle link (also denoted as inter-aerial vehicle communication or inter-drone link) comprising, e.g., an X2, SI and/or Sl-U interface. Further alternatively or in addition, the first and/or any other aerial vehicle and the one or more radio devices may be wirelessly connected in an uplink (UL) and/or a downlink (DL) through a Uu interface.

The swarm of aerial vehicles and/or the base stations of the RAN and/or the one or more radio devices may form, or may be part of, a radio network, e.g., according to the Third Generation Partnership Project (3GPP) or according to the standard family IEEE 802.11 (WiFi). The first method aspect and the second method aspect may be performed by one or more embodiments of the first aerial vehicle, and the RAN (e.g., a base station) or at least one of the other aerial vehicles within the swarm, respectively. The RAN may comprise one or more base stations, e.g., performing the second method aspect.

Any of the radio devices may be a 3GPP user equipment (UE) or a Wi-Fi station (STA). The radio device may be a mobile or portable station, a device for machine-type communication (MTC), a device for narrowband Internet of Things (NB-loT) or a combination thereof. Examples for the UE and the mobile station include a mobile phone, a tablet computer and a self-driving vehicle. Examples for the portable station include a laptop computer and a television set. Examples for the MTC device or the NB-loT device include robots, sensors and/or actuators, e.g., in manufacturing, automotive communication and home automation. The MTC device or the NB-loT device may be implemented in a manufacturing plant, household appliances and consumer electronics.

Whenever referring to the RAN, the RAN may be implemented by one or more base stations and/or by one or more aerial vehicles, e.g. the first aerial vehicle and other aerial vehicles within a swarm.

The first and/or any other aerial vehicle within the swarm may be wirelessly connected or connectable (e.g., according to a radio resource control, RRC, state or active mode) with at least one base station of the RAN and/or the other aerial vehicles within the swarm. Furthermore, the first and/or any other aerial vehicle within the swarm may be wirelessly connected or connectable with the one or more radio devices in the geographic area and/or the terrestrial area.

The aerial vehicle may comprise a drone (also denoted as RBS drone), a rotor, and/or an airplane.

The base station may encompass any station that is configured to provide radio access to any of the radio devices. The base stations may also be referred to as cell, transmission and reception point (TRP), radio access node or access point (AP). The base station and/or the relay radio device may provide a data link to a host computer providing the user data to the remote radio device or gathering user data from the remote radio device. Examples for the base stations may include a 3G base station or Node B, 4G base station or eNodeB, a 5G base station or gNodeB, a Wi-Fi AP and a network controller (e.g., according to Bluetooth, ZigBee or Z-Wave).

The RAN may be implemented according to the Global System for Mobile Communications (GSM), the Universal Mobile Telecommunications System (UMTS), 3GPP Long Term Evolution (LTE) and/or 3GPP New Radio (NR). Any aspect of the technique may be implemented on a Physical Layer (PHY), a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, a packet data convergence protocol (PDCP) layer, and/or a Radio Resource Control (RRC) layer of a protocol stack for the radio communication.

As to another aspect, a computer program product is provided. The computer program product comprises program code portions for performing any one of the steps of the method aspect disclosed herein when the computer program product is executed by one or more computing devices. The computer program product may be stored on a computer- readable recording medium. The computer program product may also be provided for download, e.g., via the radio network, the RAN, the Internet and/or a host computer. Alternatively, or in addition, the method may be encoded in a Field-Programmable Gate Array (FPGA) and/or an Application-Specific Integrated Circuit (ASIC), or the functionality may be provided for download by means of a hardware description language.

As to a first device aspect, a device for controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on a first aerial vehicle is provided. The multisector antenna system comprises one antenna per sector, and the first aerial vehicle moves within a swarm of aerial vehicles. Each aerial vehicle in the swarm comprises a multi-sector antenna system. The device may be configured to perform any one of the steps of the first method aspect.

As to a second device aspect, a device for controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within a swarm of aerial vehicles is provided. The multi-sector antenna system of each aerial vehicle comprises one antenna per sector, and each aerial vehicle moves within the swarm of aerial vehicles. The device may be configured to perform any one of the steps of the second method aspect.

As to a further first device aspect, a device for controlling a plurality of frequency bands of a multi-sector antenna system mounted on a first aerial vehicle of a RAN is provided. The multi-sector antenna system comprises one antenna per sector, and the first aerial vehicle moves within a swarm of aerial vehicles. Each aerial vehicle in the swarm comprises a multisector antenna system. The device comprises processing circuitry (e.g., at least one processor and a memory). Said memory comprises instructions executable by said at least one processor whereby the device is operative to perform any one of the steps of the first method aspect.

As to a further second device aspect, a device for controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within a swarm of aerial vehicles is provided. The multi-sector antenna system of each aerial vehicle comprises one antenna per sector, and each aerial vehicle moves within the swarm of aerial vehicles. The device comprises processing circuitry (e.g., at least one processor and a memory). Said memory comprises instructions executable by said at least one processor whereby the device is operative to perform any one of the steps of the second method aspect.

As to a still further aspect a communication system including a host computer is provided. The host computer comprises a processing circuitry configured to provide user data. The host computer further comprises a communication interface configured to forward the data to a cellular network (e.g., the RAN, the base station and/or the first and/or any other aerial vehicle within the swarm) for transmission to a UE. A processing circuitry of the cellular network is configured to execute any one of the steps of the first and/or second method aspects.

The communication system may further include the UE. Alternatively or in addition, the cellular network may further include one or more aerial vehicles configured for radio communication with the UE and/or to provide a data link between the UE and the host computer using the first and/or second method aspects. Further alternatively or in addition, the cellular network may further include one or more base stations configured for radio communication with the one or more aerial vehicles and/or the UE and/or to provide a data link between the UE and the host computer using the second method aspect.

The processing circuitry of the host computer may be configured to execute a host application, thereby providing the data and/or any host computer functionality described herein. Alternatively, or in addition, the processing circuitry of the UE may be configured to execute a client application associated with the host application.

Any one of the devices, the aerial vehicle, the UE, the base station, the communication system or any node or station for embodying the technique may further include any feature disclosed in the context of the method aspects, and vice versa. Particularly, any one of the units and modules disclosed herein may be configured to perform or initiate one or more of the steps of the method aspect.

Brief Description of the Drawings

Further details of embodiments of the technique are described with reference to the enclosed drawings, wherein: Fig. 1 shows a schematic block diagram of an embodiment of a device for controlling a plurality of frequency bands of a radio access network (RAN) of a multi-sector antenna system mounted on an aerial vehicle within a swarm of aerial vehicles;

Fig. 2 shows a schematic block diagram of an embodiment of a device for controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within a swarm of aerial vehicles;

Fig. 3 shows a flowchart for a method of controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on an aerial vehicle within a swarm of aerial vehicles, which method may be implementable by the device of Fig. 1;

Fig. 4 shows a flowchart for a method of controlling a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within a swarm of aerial vehicles, which method may be implementable by the device of Fig. 2;

Fig. 5 shows an exemplary embodiment of five drones starting from a common base and following their respective paths independently;

Fig. 6 shows and exemplary embodiment of eight drones performing circular switches of positions for RAN coverage of a terrestrial area comprising a base;

Fig. 7 schematically illustrates an exemplary scenario of handover procedures among drones when the respective RAN coverage areas change, which change may be implementable by the circular switches of positions of the exemplary embodiment of Fig. 6;

Fig. 8 schematically illustrates an exemplary deployment of one or more redundant aerial vehicles capable of taking over positions of one or more malfunctioning aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 9 shows an exemplary assignment of a plurality of frequency bands to an antenna system comprising four antennas in a swarm of four aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2; Fig. 10 shows an exemplary assignment of a plurality of frequency bands to an antenna system comprising six antennas in a swarm of seven aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 11 shows an exemplary assignment of a plurality of frequency bands to an antenna system comprising eight antennas in a swarm of nine aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 12 shows an exemplary assignment of a plurality of frequency bands to an antenna system comprising nine antennas in a swarm of nine aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 13 shows an example of a division of a two-dimensional layer into planar sectors with respect to a central aerial vehicle within a swarm of nine aerial vehicles, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 14 shows an exemplary trajectory and associated substitution of frequency bands for an aerial vehicle moving within the swarm, wherein the constellation of the swarm and the planar sectors with respect to a central aerial vehicle may be that of Fig. 13;

Fig. 15 shows an exemplary embodiment of a swarm of aerial vehicles comprised in a two- dimensional layer serving a plurality of radio devices, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 16 shows an exemplary embodiment of a swarm of aerial vehicles comprised in a three-dimensional constellation of two two-dimensional layers serving a plurality of radio devices, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 17 shows an exemplary map comprising planned positions and planned trajectories of aerial vehicles, wherein the positions may be coded, and wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2; Fig. 18 shows an example flowchart of method steps deciding on a change of a planned trajectory responsive to a signal quality and/or a signal strength measurement in relation to neighboring aerial vehicles, which method steps may be performed by an aerial vehicle embodying the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 19 shows an exemplary embodiment of a swarm of aerial vehicles comprised in a two- dimensional layer serving a plurality of radio devices, wherein the swarm of aerial vehicles comprises some aerial vehicles with a primary function and other aerial vehicles with a secondary function only, wherein any one of the aerial vehicles may embody the device of Fig. 1, and wherein the aerial vehicles with the primary function may further embody the device of Fig. 2;

Fig. 20 shows an exemplary embodiment of a swarm of aerial vehicles comprised in a three-dimensional constellation of three two-dimensional layers serving a plurality of radio devices, wherein each two-dimensional layer comprises some aerial vehicles with a primary function and other aerial vehicles with a secondary function only, wherein any one of the aerial vehicles may embody the device of Fig. 1, and wherein the aerial vehicles with the primary function may further embody the device of Fig. 2;

Fig. 21 shows an example of labelling assignments of frequency bands to antennas of aerial vehicles within one two-dimensional layer, which may comprise a first two- dimensional layer within a three-dimensional configuration, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 22 shows an alternative example of labelling assignments of frequency bands to antennas of aerial vehicles within one two-dimensional layer, which may comprise a first two-dimensional layer within a three-dimensional configuration, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 23 shows another alternative example of labelling assignments of frequency bands to antennas of aerial vehicles within one two-dimensional layer, which may comprise a second two-dimensional layer within a three-dimensional configuration, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2; Fig. 24 shows still another alternative example of labelling assignments of frequency bands to antennas of aerial vehicles within one two-dimensional layer, which may comprise a first two-dimensional layer or a second two-dimensional layer within a three-dimensional configuration, wherein any one of the aerial vehicles may embody the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 25 shows an example flowchart of generating an assignment of frequency bands fulfilling conditions for avoiding interferences among multi-sector antenna systems mounted on a swarm of aerial vehicles, wherein each aerial vehicle may be embodied by the device of Fig. 1, optionally in combination with Fig. 2, and wherein the generator being embodied by the device of Fig. 2;

Fig. 26 shows an example flowchart of checking the validity of an assignment of frequency bands in view of conditions for avoiding interferences, which may be combinable with and/or performed subsequently to the generating of the assignment of Fig. 25;

Fig. 27 shows an example flowchart of transmitting the valid assignment of frequency bands to the swarm of aerial vehicles in a fast mode, which comprises transmitting the first validated assignment, and/or in an interactive mode, which comprises transmitting all generated valid assignments, the steps of which may be combinable with the generating and/or the checking of the validity in Figs. 25 and 26, respectively;

Figs. 28 and 29 show nine different valid assignments of frequency bands for nine aerial vehicles comprising nine sectors each, wherein the different assignments may be obtained from a first assignment by permuting positions of aerial vehicles, wherein each aerial vehicle may be embodied by the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 30 shows an example flowchart of determining a substitution of the assignment of frequency bands for an aerial vehicle performing a planned trajectory change, wherein the aerial vehicle may be embodied by the device of Fig. 1, optionally in combination with Fig. 2;

Fig. 31 shows an example flowchart of determining a substitution of the assignment of frequency bands for an aerial vehicle performing a spontaneous trajectory change, wherein the aerial vehicle may be embodied by the device of Fig. 1, optionally in combination with Fig. 2; Fig. 32 shows a schematic block diagram of an aerial vehicle embodying the device of Fig. 1;

Fig. 33 shows a schematic block diagram of a controller of a swarm of aerial vehicles embodying the device of Fig. 2;

Fig. 34 schematically illustrates an example telecommunication network connected via an intermediate network to a host computer;

Fig. 35 shows a generalized block diagram of a host computer communicating via a base station or radio device functioning as a gateway with a user equipment over a partially wireless connection; and

Figs. 36 and 37 show flowcharts for methods implemented in a communication system including a host computer, a base station or radio device functioning as a gateway and a user equipment.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as a specific network environment in order to provide a thorough understanding of the technique disclosed herein. It will be apparent to one skilled in the art that the technique may be practiced in other embodiments that depart from these specific details. Moreover, while the following embodiments are primarily described for a New Radio (NR) or 5G implementation, it is readily apparent that the technique described herein may also be implemented for any other radio communication technique, including a Wireless Local Area Network (WLAN) implementation according to the standard family IEEE 802.11, 3GPP LTE (e.g., LTE-Advanced or a related radio access technique such as MulteFire), for Bluetooth according to the Bluetooth Special Interest Group (SIG), particularly Bluetooth Low Energy, Bluetooth Mesh Networking and Bluetooth broadcasting, for Z-Wave according to the Z-Wave Alliance or for ZigBee based on IEEE 802.15.4.

Moreover, those skilled in the art will appreciate that the functions, steps, units and modules explained herein may be implemented using software functioning in conjunction with a programmed microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP) or a general purpose computer, e.g., including an Advanced RISC Machine (ARM). It will also be appreciated that, while the following embodiments are primarily described in context with methods and devices, the invention may also be embodied in a computer program product as well as in a system comprising at least one computer processor and memory coupled to the at least one processor, wherein the memory is encoded with one or more programs that may perform the functions and steps or implement the units and modules disclosed herein.

Fig. 1 schematically illustrates a block diagram of an embodiment of a device for controlling, e.g., at a first aerial vehicle, a plurality of frequency bands (also denoted as repeatable sequence of frequency bands or shortly sequence of frequency bands) of a radio access network (RAN) of a multi-sector antenna system mounted on the first aerial vehicle, the multi-sector antenna system comprising one antenna per sector and the first aerial vehicle moving within a swarm of aerial vehicles, wherein each aerial vehicle in the swarm comprises a multi-sector antenna system. The device is generically referred to by reference sign 100.

The device 100 comprises a determination module 102 that is configured to determine a trajectory of the first aerial vehicle relative to other aerial vehicles within the swarm. The device 100 further comprises a transmission module 104 that is configured to transmit an indication of the determined trajectory to at least one other aerial vehicle within the swarm. The device 100 still further comprises a substitution module 106 that is configured to substitute an assignment of frequency bands to the antennas of the multi-sector antenna system mounted on the first aerial vehicle depending on the determined trajectory while the first aerial vehicle moves on the determined trajectory, wherein each antenna of the multi-sector antenna system mounted on the first aerial vehicle is assigned at least one frequency band.

Any of the modules of the device 100 may be implemented by units configured to provide the corresponding functionality. In an alternative embodiment, the modules may be implemented as functions operating in a processing circuitry executing a computer program code.

The device 100 may also be referred to as, or may be embodied by, an aerial vehicle for use within the swarm of aerial vehicles. The aerial vehicle 100 and any further aerial vehicle 100 within the swarm of aerial vehicles 100 may be in direct radio communication, e.g., at least for the transmission of the indication of the determined trajectory from the aerial device 100 to the further aerial device. Alternatively or in addition, the aerial vehicle 100 may be in direct radio communication, e.g., at least for the transmission of the indication of the determined trajectory from the aerial device 100 to a controller. Further alternatively or in addition, the aerial vehicle 100 may be in direct radio communication with at least one (e.g., terrestrially based) radio device. E.g., the at least one radio device may be served by the aerial vehicle 100. Fig. 2 schematically illustrates a block diagram of an embodiment of a device for controlling, e.g., by a controller of a swarm of aerial vehicles, a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within the swarm, the multi-sector antenna system comprising one antenna per sector and any one aerial vehicle moving within the swarm of aerial vehicles. The device is generically referred to by reference sign 200.

The device 200 comprises a determination module 202 that is configured to determine at least one of a trajectory of at least one aerial vehicle relative to at least one other aerial vehicle within the swarm and/or to determine an assignment of frequency bands to the antennas of the multi-sector antenna system of the at least one aerial vehicle within the swarm. The device 200 further comprises a transmission module 204 that is configured to transmit the determined trajectory of the at least one aerial vehicle and/or the determined assignment of the frequency bands of the at least one aerial vehicle to at least one aerial vehicle within the swarm of aerial vehicles.

Any of the modules of the device 200 may be implemented by units configured to provide the corresponding functionality, and in an alternative embodiment the modules may be implemented as functions operating in a processing circuitry executing a computer program code.

The device 200 may also be referred to as, or may be embodied by, a controller. The aerial vehicle and the controller 200 may be in direct radio communication, e.g., at least for the transmission, to the aerial device, of the determined trajectory and/or of the determined assignment of the frequency bands. The aerial vehicle may be embodied by the device 100.

Fig. 3 shows an example flowchart for a method 300 of controlling, at a first aerial vehicle 100, a plurality of frequency bands of a multi-sector antenna system mounted on the first aerial vehicle of a RAN. The multi-sector antenna system comprises one antenna per sector, and the first aerial vehicle moves within a swarm of aerial vehicles. Each aerial vehicle in the swarm comprises a multi-sector antenna system.

In a step 302, a trajectory of the first aerial vehicle relative to other aerial vehicles within the swarm is determined. In a further step 304, an indication of the determined trajectory to at least one other aerial vehicle within the swarm is transmitted. In a still further step 306, an assignment of frequency bands to the antennas of the multi-sector antenna system mounted on the first aerial vehicle is substituted depending on the determined trajectory while the first aerial vehicle moves on the determined trajectory, wherein each antenna of the multi-sector antenna system mounted on the first aerial vehicle is assigned at least one frequency band.

The method 300 may be performed by the device 100. For example, the modules 102, 104 and 106 may perform the steps 302, 304 and 306, respectively.

Fig. 4 shows an example flowchart for a method 400 of controlling, e.g., by a controller 200 of a swarm of aerial vehicles 100, a plurality of frequency bands of a RAN of a multi-sector antenna system mounted on any one aerial vehicle within the swarm. The multi-sector antenna system comprises one antenna per sector. Each aerial vehicle moves within a swarm of aerial vehicles.

In a step 402, a trajectory of at least one aerial vehicle relative to at least one other aerial vehicles within the swarm and/or an assignment of frequency bands to the antennas of the multi-sector antenna system of the at least one aerial vehicle within the swarm is determined. In a further step 404, the determined trajectory of the at least one aerial vehicle and/or the determined assignment of the frequency bands of the at least one aerial vehicle is transmitted to at least one aerial vehicle within the swarm of aerial vehicles.

The method 400 may be performed by the device 200. For example, the modules 202 and 204 may perform the steps 402 and 404, respectively.

Each frequency band may comprise a plurality of (e.g., consecutive) subcarriers and/or component carriers.

The plurality of frequency bands may be denoted as repeatable sequence of frequency bands. For example, the swarm of aerial vehicles 100 may be comprised in at least one two- dimensional layer parallel to a terrestrial plane. The plurality of frequency bands may be shared and/or may be identical for all aerial vehicles 100 within one of the at least one two- dimensional layer. Alternatively or in addition, the plurality of frequency bands associated with a two-dimensional layer may be denoted as planar repeatable sequence of frequency bands.

The swarm of aerial vehicles 100 (e.g., comprising the first aerial vehicle and other aerial vehicles) may comprise a three-dimensional arrangement of at least two two-dimensional layers. Each of the at least two two-dimensional layers may comprise a planar repeatable sequence of frequency bands. Alternatively or in addition, the frequency bands of at least two two-dimensional layers may at least partially overlap. E.g., the planar repeatable sequence of frequency bands of one two-dimensional layer may comprise a subset of frequency bands of the planar repeatable sequence of frequency bands of a further two- dimensional layer.

The (e.g., first and/any other) aerial vehicle 100 may also be denoted as aircraft. Alternatively or in addition, the (e.g., first and/any other) aerial vehicle 100 may be unmanned and/or manned.

Each sector may comprise a lobe, or a cone (e.g., of directional transmitter gain and/or directional receiver gain) and/or may be omnidirectional.

The number of one or more multi-sector antennas may be identical for each aerial vehicle 100 (e.g., comprising the first aerial vehicle and other aerial vehicles) in the swarm.

The swarm may comprise a predetermined number of aerial vehicles 100, e.g., four, nine or 16 aerial vehicles 100. The swarm of aerial vehicle 100 may be distributed on nodes of a (e.g., square) grid.

The RAN may be configured to serve a (e.g., terrestrial) plurality of radio devices.

The indication of the determined trajectory may be transmitted on at least one frequency band different from the plurality of frequency bands of the RAN.

Transmitting the indication of the determined trajectory may also be denoted as and/or may be included in an inter-aerial vehicle communication. Alternatively or in addition, the first aerial vehicle 100 may be in inter-aerial vehicle communication with at least one other aerial vehicle 100 within the swarm.

Determining the trajectory of the first aerial vehicle 100 may also be denoted as the first aerial vehicle 100 planning and/or making a maneuver. Alternatively or in addition, determining the trajectory may depend on at least one other aerial vehicle 100, e.g., if the first aerial vehicle 100 enters the swarm from the outside and/or from a boundary. Alternatively or in addition, determining the trajectory may depend on more than one or all other aerial vehicles 100 in the swarm, e.g., it the first aerial vehicle 100 is located centrally within the swarm.

By the substituting of the assignment of frequency bands to the antennas of the first aerial vehicle 100 within the swarm of aerial vehicles 100, embodiments of the (e.g., first and/or any other) aerial vehicle 100 can be safeguarded against interferences from the other aerial vehicles 100 within the swarm when the first aerial vehicle 100 moves on and/or follows the determined trajectory. Alternatively or in addition, by the substituting of the assignment of frequency bands depending on the trajectory of the first aerial vehicle 100, a jamming (e.g., of any one of the frequency bands) can be prevented.

The substituting may comprise permuting the frequency bands assigned to the antennas of the multi-sector antenna system.

By the controlling of the plurality of frequency bands, providing radio access to aerial vehicles 100 moving in three-dimensions, e.g., for flying cars, can be enabled.

The (e.g., first and/or any other) aerial vehicle 100 may comprise at least one of a drone, a rotor, and an airplane.

The drone may comprise an unmanned vessel.

The swarm of aerial vehicles 100 may provide a RAN coverage for a terrestrial area of a predetermined shape. Optionally, the predetermined shape of the terrestrial area may comprise a square. The shape of a square may also be denoted as square area.

The trajectory may comprise a list of available and/or planned positions of the aerial vehicle 100, e.g. as nodes on a grid. The grid may comprise columns and/or rows.

The multi-sector antenna system may comprise at least one of four planar sectors, six planar sectors and eight planar sectors.

Each planar sector may be horizontally tilted towards the ground.

A tilt angle relative to a terrestrial plane may be greater than thirty degrees and/or less than sixty degrees. Optionally, the tilt angle may be forty-five degrees.

The multi-sector antenna system may further comprise one vertical sector.

The vertical sector may correspond to a tilt angle of ninety degrees.

The plurality of frequency bands may be mutually orthogonal and/or (e.g., pairwise) disjoint.

The plurality of frequency bands may comprise an orthogonal frequency division multiplexing (OFDM) scheme. The plurality of frequency bands may comprise an OFDM access (OFDMA) scheme.

The plurality of frequency bands may comprises at least one of a sub-6 Giga Hertz (GHz) band and a millimeter (mm) wave band.

The plurality of frequency bands may be comprised in at least one frequency range (FR). E.g., the at least one sub-6 GHz band may be comprised in a first frequency range FR1 comprising frequencies below 6 GHz. Alternatively or in addition, the at least one mm wave band may be comprised in a second frequency range FR2 comprising frequencies above 24 GHz and/or below 52 GHz.

The sub-6 GHz bands may, e.g., comprise bandwidths of 1.4 Mega Hertz (MHz), 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, 50 MHz and/or 100 MHz. The mm wave bands may, e.g., comprise bandwidths of 200 MHz, 400 MHz, 500 MHz and/or 800 MHz.

The indication of the determined trajectory may be transmitted using an inter-aerial vehicle link on at least one frequency band different from the plurality of frequency bands of the RAN provided by the multi-sector antenna systems of the aerial vehicles (100) within the swarm.

Alternatively or in addition, the indication of the determined trajectory may be transmitted using a relayed inter-aerial vehicle link, wherein the inter-aerial vehicle link is relayed through at least one of a terrestrial base station and a core network (CN) of a wireless communications network comprising the RAN.

The swarm of aerial vehicles 100 may be comprised in a two-dimensional layer. The determined trajectory of the first aerial vehicle 100 may be comprised in the two- dimensional layer.

The two-dimensional layer may correspond to a plane parallel to the terrestrial plane.

The two-dimensional layer may also be denoted as a plane. Alternatively or in addition, the planned positions and/or trajectories of each aerial vehicle 100 within the swarm of aerial vehicles 100 may be comprised in a horizontal plane. The horizontal plane may be vertically displaced from a terrestrial plane.

The two-dimensional layer may comprise a two-dimensional grid. Planned positions may correspond to nodes on the two-dimensional grid. The swarm of aerial vehicles 100 may be comprised in a three-dimensional arrangement comprising at least two vertically displaced two-dimensional layers. The determined trajectory of the first aerial vehicle 100 may be comprised within one of the two- dimensional layers.

The at least two vertically displaced two-dimensional layers also be denoted as a three- dimensional arrangement.

All (e.g., except for a first) of the vertically displaced two-dimensional layers may comprise a layer-specific horizontal (e.g., position) offset relative to a first two-dimensional layer. Alternatively or in addition, at least two neighboring two-dimensional layers may comprise a relative horizontal (e.g., position) offset.

The horizontal offset may comprise an offset of planned positions of aerial vehicles 100, in particular of a central aerial vehicle 100 and/or aerial vehicles 100 at the boundaries of any two-dimensional layer, among the two-dimensional layers.

The plurality of frequency bands of all (e.g., except for a first) of the vertically displaced two-dimensional layers may comprise a layer-specific frequency offset relative to a first two-dimensional layer. Alternatively or in addition, at least two neighboring two- dimensional layers may comprise a relative frequency offset.

The plurality of frequency bands may comprise at least seven frequency bands and/or at most twelve frequency bands.

The plurality of frequency bands may comprise seven frequency bands for a swarm comprised in a two-dimensional layer.

The plurality of frequency bands may comprise twelve frequency bands for a swarm comprised in at least two vertically displayed two-dimensional layers.

Alternatively or in addition, the three-dimensional arrangement may comprise interlaced planar repeatable sequences of frequency bands.

The method 300 may be performed by a processing circuit, e.g., of the first aerial vehicle 100. Optionally, the processing circuit comprises a central processing unit (CPU) and/or a navigation unit of the first aerial vehicle 100. The first aerial vehicle 100 may comprise memory and/or storage. The trajectory may be determined and/or the assignment of frequency bands may be substituted based on a stored map.

The determined trajectory may, e.g., at least piecewise, comprise a planned trajectory and/or a planned position,. The planned trajectory and/or planned position may be comprised in a (e.g., stored) map. The map may be stored at the first aerial vehicle 100. The planned trajectory may also be denoted as planned path.

Alternatively or in addition, the determined trajectory may, e.g., at least piecewise, comprise a spontaneous trajectory. For example, the first aerial vehicle 100 may perform a spontaneous change of position due to an (e.g., unforeseen) obstacle, and then follow a planned trajectory from the changed position onwards.

The planned trajectory may be represented by a closed set of planar vectors.

The planar vectors may be parallel to the terrestrial plane. The closed set of planar vectors may sum up to zero. Each of the planar vectors may correspond to a segment of the planned trajectory.

The determined trajectory may further comprise a determined velocity for moving on the trajectory.

The substituting 306 of the assignment of frequency bands may be based on at least one measurement. The at least one measurement may comprise a distance of the first aerial vehicle 100 to at least one other aerial vehicle 100 within the swarm.

The at least one measurement may be a result of a step of measuring at the first aerial vehicle 100. Alternatively or in addition, the at least one measurement may comprise at least two (e.g., independent) measurements, e.g., comprising distances to at least two neighboring aerial vehicles 100 within the swarm and/or at least one distance to at least one neighboring aerial vehicle 100 and a vertical distance to the ground (e.g., for determining a position within and/or an affiliation to a two-dimensional layer, in particular within a three-dimensional arrangement).

The at least one measurement may comprise a signal strength and/or a signal quality of at least one other aerial vehicle 100 within the swarm.

The at least one other aerial vehicle 100 within the swarm may also be denoted as neighbor cell. The signal strength may be provided in arbitrary strength units (ASU) and/or may be valid for multiple wireless communication technologies.

The distances of nodes of a grid may depend on frequencies and powers used for serving a wireless device. E.g., for mm wave bands, the distances may range from 250 meters to 1.25 kilometers.

An initial assignment of frequency bands to the antennas may be determined at deployment and/or at takeoff of the (e.g., first and/or any) aerial vehicle 100.

The initial assignment may be determined for each of the aerial vehicles 100 within the swarm.

The assignment of frequency bands may be substituted during a service of the (e.g., first and/or any) aerial vehicle 100 within the swarm of aerial vehicle 100.

The indication of the determined trajectory may be encrypted. Alternatively or in addition, the indication of the determined trajectory may be comprised in a hermetic code. The hermetic code may be associated with a stored map.

The hermetic code may comprise a set of symbols and/or acronyms. Alternatively or in addition, each symbol and/or acronym in the set may be associated with a frequency band. E.g., letters A, B, C, D, E, F, G, H, I, J, K and L may be associated with a plurality of sub-6 GHz bands and/or mm wave bands, respectively.

The method 300 may comprise updating the stored map during the service of the aerial vehicle 100.

The (e.g., first and/or any) aerial vehicle 100 may comprise a primary function (also denoted as controller function and/or main function) and/or a secondary function (also denoted as standby function) within the swarm of aerial vehicles 100. The primary function may autonomously determine 302 the trajectory and/or substitute 306 the assignment of frequency bands. Alternatively or in addition, the secondary function may comprise receiving an indication of a trajectory and/or an assignment of frequency bands from at least one of the further aerial vehicles 100. The determining 302 of the trajectory and/or the substituting 306 of the frequency bands may, for the secondary function, depend on the received indication. The method 300 may further comprise or initiate serving at least one radio device on the assigned frequency bands of the antennas of the aerial vehicle 100. The method 300 may further comprise or initiate suspending a connection to the at least one radio device based on the substituting 306 of the assignment of frequency bands.

The serving and/or the connection to the at least one radio device may comprise a radio resource control (RRC) connection.

The indication of the determined trajectory may be transmitted periodically and/or a periodically.

The indication of the determined trajectory may be transmitted to at least one of the further aerial vehicles 100 within the swarm periodically. Alternatively or in addition, the indication of the determined trajectory may be transmitted to at least one of the further aerial vehicles 100 within the swarm aperiodically, e.g., based on a trigger event. A trigger event may, e.g., comprise a change in a previously planned trajectory, for example responsive to an environmental change and/or a change in settings and/or operating parameters of the aerial vehicle 100.

The indication of the determined trajectory may further comprise a rank of the aerial vehicle 100, a maximum served radio device priority of the first aerial vehicle 100, and/or an indication if the determined trajectory comprises a planned trajectory or a spontaneous trajectory.

The rank of the aerial vehicle 100 may be indicative of at least one of a strength of a power source, a communication capability, a maximum throughput, and/or an eligibility as a primary device (also denoted as controller device and/or main device).

The planned trajectory may comprise a trajectory previously stored, e.g., along with the stored map. Alternatively or in addition, the spontaneous trajectory may comprise a trajectory not previously stored.

The method 300 may further comprise or initiate at step of receiving an indication from at least one of the other aerial vehicles 100 within the swarm. The received indication may comprise a rank of the at least one other aerial vehicle 100, a maximum served radio device priority of the at least one other aerial vehicle 100, and/or an indication of a determined trajectory of the at least one other aerial vehicle 100 within the swarm. The method 300 may further comprise or initiate a step of ordering the aerial vehicles 100 within the swarm based on the indicated rank and/or the indicated maximum served radio device priority, optionally based on a product of the indicated rank and the indicated maximum served radio device priority.

The method 300 may further comprise or initiate a step of initiating a handover procedure of at least one radio device served by the first aerial vehicle 100 in one of the frequency bands that is subject to the substituting 306.

A higher ordered aerial vehicle 100 among at least two aerial vehicles 100 within the swarm may send a suspend message to the at least one radio device. Alternatively or in addition, a lower ordered aerial vehicle 100 among at least two aerial vehicles 100 within the swarm may disconnect from the radio device. Optionally the lower ordered aerial vehicle 100 may send a redirect message to the at least one radio device.

Alternatively or in addition, for aerial vehicles 100 within the swarm having the same order based on the indicated rank and/or the indicating maximum served radio device priority, the aerial vehicle 100 with the higher signal strength and/or the higher signal quality may send the suspend message.

A bandwidth of at least one frequency band within the plurality of frequency bands, and/or a total bandwidth of the plurality of frequency bands may be changed during a service of the first aerial vehicle 100.

The bandwidth of the at least one frequency band may comprise a (e.g., summed) bandwidth of the plurality of (e.g., consecutive) subcarriers and/or component carriers. Alternatively or in addition, the total bandwidth of the plurality of frequency bands may comprise a (e.g., summed) bandwidth of the frequency bands. Further alternatively or in addition, the total bandwidth may comprise a span from the lowest frequency to the highest frequency within the plurality of frequency bands.

The substituting 306 may further comprise a cyclic permutation of the assignment of frequency bands of the antennas of the first aerial vehicle 100, optionally responsive to a rotation of the aerial vehicle 100 around a vertical axis. A direction of the cyclic permutation may be opposite to a direction of the rotation.

The determining 302 of the trajectory may comprise receiving the trajectory, e.g., from a controller 200 of the swarm of aerial vehicles 100. Alternatively or in addition, the method may further comprise or initiate the step of receiving the assignment of frequency bands from a controller 200 of the swarm of aerial vehicles 100. The received assignment may be an initial assignment that is subject to the substituting. Alternatively or in addition, the received assignment may be the substituted assignment.

The controller 200 of the swarm of aerial vehicles 100 may be spaced apart from the swarm. The controller 200 may, e.g., be comprised in a terrestrial base station of the RAN and/or a satellite controlling the RAN. Alternatively or in addition, the controller 200 may be comprised (e.g., at least partially) in the primary function of one or more of the aerial vehicles 100.

If the aerial vehicle 100 comprises the secondary function, the receiving of the assignment of frequency bands and/or of the trajectory from the controller 200 may comprise receiving the assignment of frequency bands and/or of the trajectory from at least one of the further aerial vehicles 100 within the swarm comprising the primary function.

The method 300 may further comprise the steps of receiving an update massage regarding the stored map from the controller 200; and updating the stored map responsive to the received update message. Alternatively or in addition, the stored map may be updated responsive to an update message sent by the controller 200.

The controller 200 may be a terrestrial base station.

The trajectory and/or the assignment of frequency bands may be transmitted by the controller 200 to an aerial vehicle 100 comprising the primary function.

An initial assignment of frequency bands may be random. Optionally, the initial assignment may be subject to a constraint.

The constraint may be based on and/or may be provided for avoiding interferences.

The determining 402 of the assignment of frequency bands may comprise determining a first assignment compatible with a determined 402 trajectory and with a constraint.

The assignment of frequency bands may depend on a signal quality and/or a signal strength. The signal quality may comprise at least one of a minimum signal quality for at least one or each aerial vehicle 100 within the swarm and an average signal quality. The average may be taken over a subset or all aerial vehicles 100 within the swarm.

The signal quality may comprise a block error rate (BLER), a signal-to-noise ratio (SNR), and/or a signal-to-interference-and-noise ratio (SINR). The method 400 may further comprise or initiate a step of transmitting, from the controller 200 to at least one aerial vehicle 100 within the swarm, a map in relation to trajectories of each of the aerial vehicles 100 within the swarm.

The determining 402 of the assignment of frequency bands may be based on receiving an indication, by at least one aerial vehicle 100, of a trajectory determined at the at least one aerial vehicle 100.

The method 400 may be performed by a terrestrial base station.

Fig. 8 shows an exemplary swarm of aerial vehicles 804 starting from a terrestrial base 802 and circularly switching positions. One or more further aerial vehicles 806 are deployed from the terrestrial base 802 for redundancy. E.g., in case one of the serving aerial vehicles 804 malfunctions (e.g., breaks down), one of the further aerial vehicles 806 may move to the serving position of the malfunctioning aerial vehicle 804 to provide RAN coverage.

Figs. 9 to 12 show exemplary embodiments of swarms 900 of aerial vehicles 100 according to the invention.

In the exemplary embodiments of Figs. 9 to 11, the multi-sector antenna system of each aerial vehicle 100 within the swarm 900 comprises a fixed number of four, six and eight planer sectors, respectively. Each planar sector may be tilted towards the ground, e.g., at an angle of 45 degrees. The number of frequency bands in each of the exemplary embodiments of Figs. 9 to 11 equals to or is greater than the number of sectors per aerial vehicle 100 (e.g., six, six and eight, respectively).

Fig. 9 shows an exemplary embodiment of a swarm 900 comprising four aerial vehicles 100, with each aerial vehicle 100 comprising a multi-sector antenna system comprising four antennas. Each antenna is assigned a frequency band out of a plurality of six frequency bands denoted by A, B, C, D, E and F (also jointly denoted as "planar sequence" of frequency bands). The frequency bands are assigned to the antennas of the aerial vehicles 100 such that interferences are minimized. E.g., antennas assigned frequency band A of all four aerial vehicles 100 have their sector oriented in the same direction (e.g., to the upper right of Fig. 9.

Fig 10 shows an exemplary embodiment of a swarm 900 comprising seven aerial vehicles 100, with each aerial vehicle 100 comprising six antennas. Each antenna is assigned a frequency band out of a plurality of six frequency bands denoted by A, B, G, D, E and F (also jointly denoted as "planar sequence" of frequency bands). The frequency bands are assigned to the antennas of the aerial vehicles 100 such that interferences are minimized. E.g., antennas assigned frequency band A of all seven aerial vehicles 100 have their sector oriented in the same direction (e.g., to the top of Fig. 10). Fig. 11 shows an exemplary embodiment of a swarm 900 comprising nine aerial vehicles 100, with each aerial vehicle 100 comprising eight antennas. Each antenna is assigned a frequency band out of a plurality of eight frequency bands denoted by A, B, C, D, E, F, G and H (also jointly denoted as "planar sequence" of frequency bands). The frequency bands are assigned to the antennas of the aerial vehicles 100 such that interferences are minimized. E.g., antennas assigned frequency band A of all seven aerial vehicles 100 have their sector oriented in the same direction (e.g., to the top of Fig. 11).

In any one of the exemplary embodiments disclosed herein, all-time division duplex (a 11- TDD) like radio field planning may be excluded and/or need not be excluded.

Fig. 12 shows an exemplary embodiment of a swarm 900 of nine aerial vehicles 100 according to the invention. The swarm 900 comprises nine aerial vehicles 100 covering a terrestrial area of square shape (e.g., divided into a grid comprising three columns and three rows. Each aerial vehicle 100 comprises eight planar sectors (e.g., horizontally tilted down towards the ground) and one vertical sector (e.g., directed vertica lly towards the ground). The plurality of frequency bands comprises seven frequency bands denoted by A, B, C, D, E, F and G. The plurality of frequency bands in Fig. 12 is irregularly distributed, e.g., to avoid interferences.

The swarm of aerial vehicles 100 of Fig. 12 is comprised in a two-dimensional layer (which may also be denoted as a "carpet").

The example of a swarm of aerial vehicles 100 comprised in a two-dimensional layer may be generalized to a three-dimensional arrangement (also denoted as "three-dimensional layer" or "cube") comprising two or more two-dimensional layers. In a three-dimensional arrangement, the plurality of frequency bands comprises a total of twelve frequency bands, e.g., denoted by A, B, C, D, E, F, G,H, I, J, K and L, e.g., to avoid interferences as exemplified further below.

Aerial vehicles 100 may maneuver between other aerial vehicles 100 without interfering by planning a trajectory change and frequency band switches in positions, where they are needed, e.g., to avoid interferences.

In the examples of Figs. 13 and 14, a central aerial vehicle 100 of the configuration of nine aerial vehicles 100 with nine sectors each is shown. The planar sectors are labeled by Vertical (Top or Bottom), Horizontal (Left or Right), Diagonal Bottom (Left or Right) and Diagonal Top (Left or Right). The boundaries between neighboring sectors are shown at reference sign 1302.

In the example of Fig. 14, an aerial vehicle 100 approaching from the Diagonal-Bottom Right direction follows the trajectory 1402 in order to fill a position at the Vertical Top. The position at the Vertical Top may, e.g., be vacant (also denoted as "gap") due to a malfunctioning aerial vehicle 100 previously positioned there. At each crossing of a boundary among neighboring planar sectors of the aerial vehicle 100 in the central position, the assignment of frequency bands of the moving aerial vehicle 100 is substituted (also denoted as "changed") as depicted at reference sing 1302. The substitution of the assignment of frequency bands may also be denoted as "band conversion".

An aerial vehicles 100 may give up its served radio devices (e.g., UEs) and temporarily stop serving the RAN coverage to change the position spontaneously (e.g., immediately and/or differently from a previously planned trajectory) for the purpose of dodging obstacles and/or in case natural disasters, e.g., comprising bird strike, weather phenomena such as lightning strike, rock fragments in case of a rock fall and/or a landslide, e.g., in a mountainous area.

The aerial vehicle 100 may comprise, e.g., a drone, plane, rotor, and/or multirotor aircraft as machine conventionally able to perform spontaneous changes of trajectorys.

Fig. 14 shows an example of a repeatable sequence of seven frequency bands in a constellation of up to nine aerial vehicles 100 providing RAN coverage for a square terrestrial area with each aerial vehicle 100 comprising nine sectors. The nine sectors comprise eight planar sectors and one vertical sector per aerial vehicle 100.

The constellation of up to nine aerial vehicles 100 may be repeatable within a two- dimensional layer by repeating the constellation side-by-side. Interferences among the aerial vehicles 100 within the two-dimensional layer may be avoided by using a repeatable planar sequence satisfying a set of conditions, as exemplified in Fig. 12.

In the example of Fig. 14, the assignment of frequency bands to positions corresponds to the exemplary assignment of frequency bands displayed for all nine aerial vehicles 100 in Fig. 12. Fig. 14 shows the aerial vehicle 100 in the central position as well as one aerial vehicle 100, which substitutes the assignment of frequency bands as it moves along the planned trajectory 1402. When moving on the planned trajectory 1402, the aerial vehicle 100 may change and/or suspend RRC connections to UEs and substitute the assignment of the frequency bands at the crossings of diagonal lines as depicted at reference sign 1302.

According to the technique disclosed herein, constellations of aerial vehicles 100 comprising one two-dimensional layer can provide wireless services (e.g., to radio devices in a geographical area), swap places and maneuver using exactly seven frequency bands for the wireless service. Alternatively or in addition, a prioritization of substituting the frequency bands when aerial vehicles 100 meet and/or appear within a short distance of each other is provided.

The number of frequency bands within the (e.g., repeatable) sequence of frequency bands (also denoted as the plurality of frequency bands) depends on the constellation. If all aerial vehicles 100 are located within a two-dimensional layer (also denoted as carpet), seven frequency bands are required. If the aerial vehicles 100 are located in at least two vertically displaced two-dimensional layers (denoted as three-dimensional constellation or cube), twelve frequency bands are required.

According to an embodiment, the swarm and/or the RAN coverage provided by the swarm may comprise a constellation of aerial vehicles 100, each provided with eight symmetric (e.g., planar) sector antennas onboard and one sector directed to bottom (e.g., a vertical sector), comprising (e.g., repeated) sub-constellations of nine aerial vehicles 100, serving a RAN and/or wireless coverage for radio devices (e.g., UEs) using seven frequency bands (also denoted as carriers) with subcarriers according to an OFDMA method and communicating with each other (e.g., one aerial vehicle 100 with in the swarm with a second aerial vehicle 100 in the swarm) in a separate omni-directional, sector- and/or conedirectional inter-aerial vehicle link, e.g., in a sub-6 GHz, millimeter wave radio, Light Amplification by Stimulated Emitter Radiation (LASER), Infrared Amplification by Stimulated Emitter Radiation (IRASER), and/or Microwave Amplification by Stimulated Emitter Radiation (MASER) physical channels.

Figs. 15 and 16 show an RAN 1500 including a swarm of aerial vehicles 100 comprised in one two-dimensional layer (also denoted as carpet) and in a three-dimensional constellation (also denoted as cube) comprising two two-dimensional layers, respectively, serving a plurality of radio devices (e.g., UEs) 704 using directional sectors 1508. The aerial vehicles 100 are configured to wirelessly communicate within the swarm over an interaerial vehicle link (also denoted as inter-drone link) 1502. At least one aerial vehicle within the swarm is configured for wirelessly communicating with and/or in a coverage area of a terrestrial base station (e.g., a generalized NodeB, gNB, according to 3GPP NR) 1504 of the RAN.

In Fig. 16, the aerial vehicles 100-1 within a first two-dimensional layer are shown with white (or empty) areas. The aerial vehicles 100-2 within the second two-dimensional layer, which is displaced by a (e.g., horizontal) position offset from the first two-dimensional layer of the three-dimensional constellation, are shown with shaded areas.

The aerial vehicles 100; 100-1; 100-2 are placed in the air (or on the surface in similar attitude). In exemplary embodiments, the aerial vehicles 100; 100-1; 100-2 comprise flying drones, and/or flying cars. Herein, the semicolon in a list may correspond to "and/or". The first and/or any other aerial vehicle 100 within the swarm may have at least one CPU onboard and navigation units able to read measurements from antennas, plan their trajectory (also denoted as path) on a stored (also denoted as preloaded) map with (e.g., coded) positions of service and communicate their planning in the inter-aerial vehicle (also denoted as inter-drone or inter vessel) data channel. The (e.g., whole and/or overall) constellation of planned service places of the aerial vehicles 100 within the swarm may be planned as moving at a predetermined velocity (e.g., at a low and/or serving speed) over a trajectory consisting of and/or composed of single vectors. The vectors may close in a geometrical figure for the sake of serving the wireless and/or RAN coverage continuously.

Fig. 17 shows an example of a stored map 1700 comprising planned positions 1704 of aerial vehicles on a, e.g., cartographic, grid (also denoted as cartographic net). The planned trajectory 1402 of an aerial vehicle may start from the point reference sign 1702, e.g., coded as "Sydney". Further coded positions are exemplified at reference sign 1706 and may, e.g., comprise "Malay", "Java", "Philippines", "New Zealand" and "Thai" as code words.

Each aerial vehicle 100 may have (e.g., denoted as planar) antenna sectors directed from horizontally till 45 degrees tilted to the ground. One (e.g. denoted as vertical) sector antenna on the aerial vehicle 100 may be directed directly down to the surface.

Each time the network, e.g., comprising the swarm of aerial vehicles 100, is deployed, one or more measurements may be performed. Detecting an inappropriate (e.g., smaller than a predetermined lower threshold value and/or larger than a predetermined upper threshold value) distance, e.g., of the first aerial vehicle 100, from another cell (e.g., another aerial vehicle 100), may be reported to a controller 200 (also denoted as control center), and/or the distance (e.g., a position and/or a trajectory of the first aerial vehicle 100) may corrected automatically by alarming other aerial vehicles 100 (also denoted as vessels) within the swarm and moving the planned placement and/or the planned trajectory of the first and/or any other one of the aerial vehicles 100 on a map (e.g., the map 1700). The first and/or any other one of the aerial vehicles 100 may then perform the planned trajectory change (e.g., as described later). The one or more measurements may continue during the performance of the service (e.g., while the first and/or any other one of the aerial vehicles 100 is deployed).

Fig. 18 shows an exemplary flowchart, in which an aerial vehicle 100 (e.g., an RBS drone) decides on changing a planned trajectory depending on the result of a signal strength and/or signal quality measurement. The change of the planned trajectory may comprise one or more corrections in coded placements and/or coded planned positions on the map. The decision of changing the planned trajectory may be performed individually (also denoted as manually) by the aerial vehicle 100, e.g., by itself, and/or collectively (also denoted as automatically) by the swarm, e.g., by a controller 200.

At reference sign 1802 in Fig. 18, a first aerial vehicle 100 (e.g., an RBS drone) starts after a change in trajectory to a planned position (e.g., upon deployment of the first aerial vehicle 100). At reference sign 1804, the first aerial vehicle 100 performs one or more measurements of a signal strength and/or signal quality of neighboring aerial vehicles 100 (also denoted as neighboring cells). If the measured signal power (e.g., signal strength and/or signal quality) at reference sign 1806 is lower than a predetermined threshold, e.g., less than 1.1 (e.g., in ASU), at reference sign 1808, the first aerial vehicle 100 repeats the one or more measurements. If the measured signal power (e.g., signal strength and/or signal quality) at reference sign 1806 exceeds the predetermined threshold, e.g., is greater than 1.1 (e.g., in ASU), at reference sign 1810, the first aerial vehicle 100 determines if autocorrections are enabled at reference sign 1812. If auto-corrections are enabled as displayed at reference sign 1814, the first aerial vehicles 100 transmits a message to one or more other aerial vehicles 100 (also denoted as RBS vessels) and moves the planned position in a direction opposite to the neighboring aerial vehicles 100 (also denoted as neighbor cell) by five percent (5%) of the current distance, as shown at reference sign 1816. If autocorrections are not enabled as displayed at reference sign 1818, the first aerial vehicles 100 logs the event of the too close position and sends a message to the controller 200 (also denoted as control center) at reference sign 1820. After the step 1816 or 1820 is performed, at reference sign 1822 one or more further measurements of signal strength and/or signal quality of neighbor cells are performed at the steps displayed in Fig. 18 are repeated, until the steps are ended in the first aerial vehicle 100 at reference sign 1824 (e.g., when the first aerial vehicle 100 finishes its service within the swarm).

Each aerial vehicle 100 may plan the progressive change in the constellation (e.g., of the swarm of aerial vehicles) and communicate it together with other information on the interaerial vehicle link (also denoted as inter-aerial vehicle channel), and/or its maneuver may be regarded as spontaneous. The communication may comprise the kind of maneuver which is to be performed, the current position and/or nearest wanted position in the constellation. The communication may be encrypted to avoid interception. The communication may use hermetic codes corresponding to the (e.g., digital) map stored (also denoted as preloaded) at any one or each of the aerial vehicles 100, e.g., as exemplified in Fig. 17. The codes may be sent encrypted, and/or the map need not be sent (and/or may not be sent) over the air (e.g., using the wireless inter-aerial vehicle link) until a strong need for data (and/or, e.g., optionally software) update and/or upgrade exists in the air, e.g., while any one or all of the aerial vehicles 100 of the swarm provide RAN coverage over the (e.g., predetermined) geographic area.

A sub-constellation (e.g., of a larger swarm of aerial vehicles 100) may comprise a set of nine aerial vehicles 100 placed in a shape near a square (e.g., as shown in Fig. 12), where eight aerial vehicles 100 are located on the borders and/or the corners relative to a central aerial vehicle 100. A distance (e.g., among the aerial vehicles 100 within the subconstellation and/or within the swarm, and/or between the aerial vehicles 100 and the ground, on which one or more radio devices may be served) may correspond to a frequency (e.g., a central and/or baseband frequency of a frequency band) and/or power used for providing the wireless service. E.g., for millimeter wave frequency bands the distance may be in the range between 250 meters to 1.25 km. The aerial vehicles 100 at the corners may be at a slightly longer distance from the central aerial vehicle 100, e.g., compared to neighboring aerial vehicles within a column and/or a row of a grid.

The square around an aerial vehicle 100, which has one corner nearest the central aerial vehicle 100 (also denoted as vessel), may be the closest one where service is possible, and the corner on the other end of the diagonal may be in the same distance from aerial vehicles (also denoted as vessels) in another sub-constellation, e.g., a further set of nine aerial vehicles 100 placed in a shape near a square.

The square may be the area of the, or each, sub-constellation, and may be used to plan trajectories of aerial vehicles 100. In case the aerial vehicle 100 is moving with a planned trajectory change, it may be moving from the center of one square to another, even in a chain. The aerial vehicle 100 may change its frequency bands (also denoted as service carriers) according to a scheme planned for the service area in the sub-constellation.

In a 3D deployment, sub-constellations of two-dimensional layers may be placed one over another (e.g., along a vertical direction relative to the ground).

Fig. 19 shows an example embodiment of a swarm of aerial vehicles 100 within a two- dimensional layer. The example embodiment of Fig. 19 may be a generalization of and/or may be compatible with the example embodiment of Fig. 15.

The example embodiment of Fig. 19 may comprise several sub-constellations. Alternatively or in addition, the aerial vehicles in Fig. 19 may comprise some aerial vehicles 100-M with a primary function (e.g., configured to perform the method 300 and at least partially the method 400) and some other aerial vehicles 100-S with a secondary function only (e.g., configured to perform the method 300). Fig. 20 shows an example embodiment of a swarm of aerial vehicles 100 comprising a three- dimensional constellation with three two-dimensional layers. The example embodiment of Fig. 20 may be a generalization of and/or may be compatible with the example embodiment of Fig. 16.

The example embodiment of Fig. 20 may comprise several sub-constellations. Alternatively or in addition, the aerial vehicles in Fig. 20 may comprise some aerial vehicles 100-1M; 100- 2M; 100-3M per two-dimensional layer with a primary function (e.g., configured to perform the method 300 and at least partially the method 400) and some other aerial vehicles 100-1S; 100-2S; 100-3S per two-dimensional layer with a secondary function only (e.g., configured to perform the method 300).

In Fig. 20, the third two-dimensional layer may comprise a repetition of the assignments of frequency bands of the first two-dimensional layer. Alternatively or in addition, the second two-dimensional layer may comprise horizontally displaced planned positions (also denoted as horizontal offset) of aerial vehicles 100-2M; 100-2S relative to the first two- dimensional layer and/or the third two-dimensional layer comprising aerial vehicles 100- 1M; 100-1S and 100-3M; 100-3S, respectively. Further alternatively or in addition, the relative horizontal displacement of the first two-dimensional layer and the third two- dimensional layer may be vanishing and/or may comprise a zero offset.

Alternatively or in addition, a swarm comprising a two-dimensional layer may be changed to a three-dimensional constellation by assigning a (e.g., layer-specific) frequency offset to (e.g., each of) the frequency bands within any one of the two-dimensional layers of the three-dimensional constellation.

Conventionally, a three-dimensional constellation uses at least 24 frequency bands, e.g., to avoid interferences from neighboring antennas. By contrast, according to the technique disclosed herein, only twelve frequency bands are needed, e.g., to avoid interferences from neighboring antennas. The neighboring antennas may refer to antennas within one two- dimensional layer and/or to antennas comprised in neighboring vertically displaced two- dimensional layers.

An example of denominating positions within a two-dimensional layer corresponding to a (e.g., approximately square) area relative to a central aerial vehicle 100 and/or comprised in three columns and three rows for a set of nine aerial vehicles 100 is as shown in Fig. 13. Alternatively or in addition, a planned trajectory change of a moving aerial vehicle 100 may be as shown at reference sign 1402 in Fig. 14. In the case when an aerial vehicle's 100 maneuvers are performed because of urgent need, like broken part (e.g., at the aerial vehicle 100) and/or avoiding an (e.g., external) attack, the trajectory change may be regarded as spontaneous.

A computing device (e.g., a CPU at the aerial vehicle 100 and/or at a controller 200) may prepare the planned (and/or predicted) position(s) between waypoints. A planned trajectory change may be communicated, e.g., with (for example hermetic) codes and/or times of reaching the planned positions (also denoted as service points) on a map.

The aerial vehicles 100 within a swarm may communicate (e.g., periodically) between each other on (e.g., different and/or separate) frequency bands (e.g., on an inter-aerial vehicle link and/or inter-vessel link) differing from the (e.g., plurality of) frequency bands for providing the RAN coverage and/or service to radio devices. The aerial vehicles 100 may communicate the rank of the aerial vehicle 100 (also denoted as aerial vehicle rank or vessel rank), the maximum served radio device priority, and/or if the aerial vehicle 100 is currently moving spontaneously or planned.

The aerial vehicle rank may be set prior to the launch and/or the deployment by the Carrier and/or operator of the swarm of aerial vehicles 100. The aerial vehicle rank may be based on a power source, on communication abilities (e.g. a maximum throughput), or/or a specialization (e.g. an aerial vehicle 100 comprising a primary function, a core network (CN) equipped drone, and/or higher links in an inter-aerial vehicle link or inter-drone link). The aerial vehicle rank may be a number enabling a prioritization within the swarm (and/or network) during changes of trajectories. The biggest rank of aerial vehicle 100 may correspond to the highest value if the power source, the communication abilities and/or specializations of the aerial vehicle 100 are as high as possible.

A higher served radio device priority may be bound to those radio devices who comprise a higher priority and/or responsibility for safety of other subscribers, e.g., comprising radio devices associated to rescue, medical services and/or technical support.

By ordering aerial vehicles 100 according to a (e.g., maximum) served radio device priority, focus may be put on enabling the communication of high priority radio devices with others. The (e.g., maximum) served radio device priority may be a number provided for enabling prioritization of services for radio devices (e.g., UEs) during trajectory changes. The higher the rank is, the more prioritized the served radio device (e.g., the UE) may be.

Both rank and priority may be (e.g., unique and/or conclusive) numbers to enable quick prioritization, e.g., of an aerial vehicle 100, without sophisticated queuing and determining (e.g., calculating) during a trajectory change. E.g. according to an exemplary embodiment that is combinable with any other embodiment, if a Carrier and/or operator is known to have 10,000 aerial vehicles 100 in the stock, the higher and/or highest rank may be 90,000, and/or the lower and/or lowest rank may be 10,000. Alternatively or in addition, multithousand gaps may be left between to enable scaling (e.g., altering differences between neighbors) or/or swapping of those numbers of adding the aerial vehicles 100 to the swarm.

Alternatively or in addition, according to an exemplary embodiment that is combinable with any other embodiment, if the Carrier network and/or operator can serve 10,000,000 subscribers (e.g., conventionally a maximum of a few hundreds of subscribers may be served by a swarm of aerial vehicles, also denoted as aerial vehicle network), the highest priority may be 100,000,000 and/or the lowest 1,000,000, such that numbers can be scaled (e.g., swapped and/or added) in the crowd of all subscriptions.

The above numbers are provided as exemplary embodiments.

The radio device priority and/or the aerial vehicle rank can be on the same order of magnitude. If so, the (e.g., equal) multiplication of the priority and the rank may occur when determining (e.g., calculating) a priority of a trajectory change. Alternatively or in addition, the aerial vehicle 100 with better ASU (signal strengths in different wireless technologies) in the inter-aerial vehicle link (also denoted as inter-drone link) may have priority in taking the new place.

The aerial vehicles 100, e.g., of a swarm comprised in one two-dimensional layer, may provide RAN coverage and/or service using seven orthogonal frequency bands (e.g., which can contain subcarriers according to OFDMA scheme). The seven frequency bands may be orthogonal for all (e.g., frequency) spectrum used the terrestrial network (e.g., a terrestrial base station) below or similar, e.g., around them.

A basic sub-constellation of a serving constellation may in particular comprise nine aerial vehicles 100 keeping planned distances and places in a rectangular and/or approximately square constellation.

Each of the nine aerial vehicles in a 2D deployment may have nine sectors. Alternatively or in addition, one of seven frequency bands may be matched to each sector in the constellation in the used frequency and/or sector distribution scheme for the subconstellation. Fig. 12 depicts one exemplary embodiment with the seven frequency bands labeled by A, B, C, D, E, F and G. In a 3D deployment, aerial vehicles 100 in a first two-dimensional layer (also denoted as Layer 1) may have (e.g., each) nine sectors using one of twelve frequency bands. The aerial vehicles 100 in a second two-dimensional layer (also denoted as Layer 2) may have (e.g., each) nine sectors using, e.g., the same, twelve frequency bands.

If aerial vehicles 100 swap their places in a constellation, an automatic substitution (also denoted as swap) of frequency bands may be performed for provision of the RAN coverage and/or service according to the frequency and/or sector distribution scheme for the subconstellation by comparing, e.g., an aerial vehicle rank and a highest (also denoted as maximum) served radio device priority between the aerial vehicles 100 (e.g., drones) which could interfere during movement.

The frequency and/or sector distribution schemes for the sub-constellations comprising one two-dimensional layer may be parameterized by any set of values, e.g., belonging to the seven letters "A-G". Each A, B, C, D, E, F, G may be a frequency band (also denoted as carrier) orthogonal to others with subcarriers (e.g., a bandwidth may comprise 1.4 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, 50 MHz and/or 100MHz for sub-6 GHz band 5G radios, and/or 200 MHz, 400 MHz, 500 MHz, and/or even 800 MHz conventionally accessible in 5G millimeter wave radios).

Alternatively or in addition, the values of frequency bands and bandwidths for three- dimensional constellations under any of the twelve symbols A, B, C, D, E, F, G, H, I, J, K, L as well as total bandwidths may be changed on the fly using a procedure (e.g., as detailed below) for band conversion in case an interference and/or jamming is detected. In such a case, the discarded frequency band may be replaced on all aerial vehicles 100, e.g., within at least one two-dimensional layer and/or within all two-dimensional layers of the three- dimensional constellation, at once. Alternatively or in addition, frequency hopping during the time of service may be performed for jamming prevention.

An example of an assignment of seven frequency bands labeled by A, B, C, D, E, F and G is displayed in Fig. 12 for a two-dimensional sub-constellation (also denoted as "Layer 1").

Fig. 21 shows an embodiment of an assignment of a plurality of frequency bands that may generally be used for a first two-dimensional layer (also denoted as "Layer 1") of a two- dimensional constellation (e.g., comprising only the first two-dimensional layer) and/or of a three-dimensional constellation comprising at least one more two-dimensional layerin a two-dimensional constellation, the set of frequency bands belonging to the seven frequency bands (also denoted as carriers) may be determined by satisfying the following set of conditions (e.g., frequency band x belongs to a set of all bands in {,} but not the frequency bands as listed in / {...}: x belongs to {A,B,C,D,E,H} / { y , f, m2, n2, k3 ,m4, n4, t } y belongs to {A,B,C,D,E,H} / { x, z, m2, n2, k2, t } z belongs to {A,B,C,D,E,H} / { y, h, k2, n2, s9 p8, f8, t } f belongs to {A,B,C,D,E,H} / { x, g, m4, n4, k4, t } h belongs to {A,B,C,D,E,F,G} / { z, I, p8, f8, s8, t } g belongs to {A,B,C,D,E,F,G} / { f, I, k4, n4, m5, p6, 06, t } I belongs to {A,B,C,D,E,F,G} / { g, i, p6, 06, m6, t } i belongs to {A,B,C,D,E,F,G} / { I, h, m6, 06, p7, s8, f8, t } p2 belongs to {A,B,C,D,E,F,G} / { o2, y2, m3, n3, k5, s6, r6, t2 } y2 belongs to {A,B,C,D,E,F,G} / { p2, s2, s6, r6, k6, t2 } s2 belongs to {A,B,C,D,E,F,G} / { y2, r2, p9, f9, s7, k6, r6, t2 } o2 belongs to {A,B,C,D,E,F,G} / { p2, m2, m3, n3, k3, t2 } r2 belongs to {A,B,C,D,E,F,G} / { s2, k2, p9, f9, s9, t2 } m2 belongs to {A,B,C,D,E,F,G} / { o2, n2, k3, n3, m4, x, y, t2 } n2 belongs to {A,B,C,D,E,F,G} / { m2, k2, x, y, z, t2 } k2 belongs to {A,B,C,D,E,F,G} / { n2, r2, z, y, p8, s9, f9, t2 } p3 belongs to {A,B,C,D,E,F,G} / { f3, o3 , m9, o9, k7, s5, f5, t3 } o3 belongs to {A,B,C,D,E,F,G} / { p3, m3, s5, r5, k5, t3 } m3 belongs to {A,B,C,D,E,F,G} / { o3, n3, k5, r5, s6, p2, o2, t3 } f3 belongs to {A,B,C,D,E,F,G} / { p3, s3, m9, n9, k9, t3 } s3 belongs to {A,B,C,D,E,F,G} / { f3, r3, k9, n9, m8, p4, o4, t3 } r3 belongs to {A,B,C,D,E,F,G} / { s3, k3, p4, o4, m4, t3 } k3 belongs to {A,B,C,D,E,F,G} / { r3, n3, m4, o4, x , m2, o2, t3 } n3 belongs to {A,B,C,D,E,F,G} / { m3, k3, p2, o2, m2, t3 } p4 belongs to {A,B,C,D,E,F,G} / { o4, f4 , m8, n8, k9, s3, r3, t4 } o4 belongs to {A,B,C,D,E,F,G} / { p4, m4, s3, r3, k3, t4 } m4 belongs to {A,B,C,D,E,F,G} / { o4, n4, k3, r3, m2, x, f, t4 } f4 belongs to {A,B,C,D,E,F,G} / { p4, s4, m8, n8, k8, t4 } s4 belongs to {A,B,C,D,E,F,G} / { f4, r4, p5, o5, m7, k8, n8, t4 } r4 belongs to {A,B,C,D,E,F,G} / { s4, k4, p5, o5, m5, t4 } k4 belongs to {A,B,C,D,E,F,G} / { n4, r4, g, f, p6, m5, o5, t4 } n4 belongs to {A,B,C,D,E,F,G} / { m4, k4, x, f, g, t4 } p5 belongs to {A,B,C,D,E,F,G} / { f5, o5, s4, r4, k8, m7, n7, t5 } o5 belongs to {A,B,C,D,E,F,G} / { p5, m5, s4, r4, k4, t5 } m5 belongs to {A,B,C,D,E,F,G} / { n5, o5, k4, r4, g, p6, f6, t5 } f5 belongs to {A,B,C,D,E,F,G} / { p5, s5, m7, n7, k7, t5 } s5 belongs to {A,B,C,D,E,F,G} / { f5, r5, k7, n7, m9, p3, o3, t5 } r5 belongs to {A,B,C,D,E,F,G} / { k5, s5, p3, o3, m3, t5 } k5 belongs to {A,B,C,D,E,F,G} / { n5, r5, s6, f6, p2, m3, o3, t5 } n5 belongs to {A,B,C,D,E,F,G} / { m5, k5, p6, f6, s6, t5 } p6 belongs to {A,B,C,D,E,F,G} / { f6, 06, g, I, k4, m5, n5, t6 } 06 belongs to {A,B,C,D,E,F,G} / { m6, p6, g, I, i, t6 } m6 belongs to {A,B,C,D,E,F,G} / { n6, 06, i, I, s8, p7, f7, t6 } f6 belongs to {A,B,C,D,E,F,G} / { p6, s6, m5, n5, k5, t6 } s6 belongs to {A,B,C,D,E,F,G} / { f6, r6, k5, n5, m3, p2, y2, t6 } r6 belongs to {A,B,C,D,E,F,G} / { s6, k6, p2, y2, s2, t6 } k6 belongs to {A,B,C,D,E,F,G} / { n6, r6, s7, f7, p9, s2, y2, t6 } n6 belongs to {A,B,C,D,E,F,G} / { m6, k6, p7, f7, s7, t6 } p7 belongs to {A,B,C,D,E,F,G} / { f7, o7, s8, r8, i, m6, n6, t7 } o7 belongs to {A,B,C,D,E,F,G} / { p7, m7, s8, r8, k8, t7 } m7 belongs to {A,B,C,D,E,F,G} / { o7, n7, k8, r8, s4, p5, f5, t7 } f7 belongs to {A,B,C,D,E,F,G} / { p7, s7, m6, n6, k6, t7 } s7 belongs to {A,B,C,D,E,F,G} / { f7, r7, k6, n6, s2, p9, o9, t7 } r7 belongs to {A,B,C,D,E,F,G} / { s7, k7, p9, o9, m9, t7 } k7 belongs to {A,B,C,D,E,F,G} / { n7, r7, m9, o9, p3, s5, f5, t7 } n7 belongs to {A,B,C,D,E,F,G} / { m7, k7, p5, f5, s5, t7 } p8 belongs to {A,B,C,D,E,F,G} / { f8, 08, s9, r9, k2, z, h, t8 } 08 belongs to {A,B,C,D,E,F,G} / { p8, m8, s9, r9, k9, t8 } m8 belongs to {A,B,C,D,E,F,G} / { 08, n8, k9, r9, s3, p4, f4, t8 } f8 belongs to {A,B,C,D,E,F,G} / { p8, s8, z, h, i, t8 } s8 belongs to {A,B,C,D,E,F,G} / { f8, r8, i, h, m6, p7, o7, t8 } r8 belongs to {A,B,C,D,E,F,G} / { s8, k8, p7, o7, m7, t8 } k8 belongs to {A,B,C,D,E,F,G} / { r8, n8, m7, o7, p5, s4, f4, t8 } n8 belongs to {A,B,C,D,E,F,G} / { m8, k8, p4, f4, s4, t8 } p9 belongs to {A,B,C,D,E,F,G} / { f9, o9, s2, r2, k6, s7, r7, t9 } o9 belongs to {A,B,C,D,E,F,G} / { m9, p9, s7, r7, k7, t9 } m9 belongs to {A,B,C,D,E,F,G} / { n9, o9, k7, r7, s5, p3, f3, t9 } f9 belongs to {A,B,C,D,E,F,G} / { p9, s9, s2, r2, k2, t9 } s9 belongs to {A,B,C,D,E,F,G} / { f9, r9, k2, r2, z, p8, 08, t9 } r9 belongs to {A,B,C,D,E,F,G} / { k9, s9, p8, 08, m8, t9 } k9 belongs to {A,B,C,D,E,F,G} / { n9, r9, m8, 08, p4, s3, f3, t9 } t6 belongs to {A,B,C,D,E,F,G} / { p6, 06, m6, f6, n6, s6, r6, k6 } t7 belongs to {A,B,C,D,E,F,G} / { p7, o7, m7, f7, n7, s7, r7, k7 } t8 belongs to {A,B,C,D,E,F,G} / { p8, 08, m8, f8, n8, s8, r8, k8 } t9 belongs to {A,B,C,D,E,F,G} / { p9, o9, m9, f9, n9, s9, r9, k9 }

For a three-dimensional constellation, an assignment of twelve frequency bands within the first layer (also denoted as Layer 1) may be labeled by A, B, C, D, E, F, G, H, I, J, K and L as exemplified in Fig. 22.

Alternatively or in addition, the assignment of twelve frequency bands within the first layer (also denoted as Layer 1) may correspond to the example shown in Fig. 21.

The assignment of twelve frequency bands within the second layer (also denoted as Layer 2) of a three-dimensional constellation may also be the set of the twelve letters A, B, C, D, E, F, G, H, I, J, K and L (or a subset thereof), as exemplified in Fig. 23.

Fig. 24 provides an alternative set of labels of assignments of frequency bands for a three- dimensional sub-constellation comprising nine aerial vehicles 100 in the first two- dimensional layer (also denoted as Layer 1) and/or the second two-dimensional layer (also denoted as Layer 2).

For a three-dimensional constellation, the plurality of frequency bands (also denoted as the set of frequency bands, or briefly the set of frequencies) belonging to twelve frequency bands (also denoted as carriers) may satisfy the following conditions for Layer 1 and/or Layer 2, including conditions of avoiding interferences of Layer 2 to Layer 1 (e.g., band x belongs to set of all bands in {,} but not bands as listed in / {...}: x belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { y , f, m2, n2, k3 ,m4, n4, t } y belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { x, z, m2, n2, k2, t } z belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { y, h, k2, n2, s9, p8, f8, t } f belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { x, g, m4, n4, k4, t } h belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { z, i, p8, f8, s8, t } g belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f, I, k4, n4, m5, p6, 06, t }

I belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { g, i, p6, 06, m6, t } i belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { I, h, m6, 06, p7, s8, f8, t } p2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o2, y2, m3, n3, k5, s6, r6, t2 } y2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p2, s2, s6, r6, k6, t2 } s2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { y2, r2, p9, f9, s7, k6, r6, t2 } o2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p2, m2, m3, n3, k3, t2 } r2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s2, k2, p9, f9, s9, t2 } m2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o2, n2, k3, n3, m4, x, y, t2 } n2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m2, k2, x, y, z, t2 } k2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n2, r2, z, y, p8, s9, f9, t2 } p3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f3, o3 , m9, n9, k7, s5, r5, t3 } o3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p3, m3, s5, r5, k5, t3 } m3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o3, n3, k5, r5, s6, p2, o2, t3 } f3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p3, s3, m9, n9, k9, t3 } s3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f3, r3, k9, n9, m8, p4, o4, t3 } r3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s3, k3, p4, o4, m4, t3 } k3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r3, n3, m4, o4, x , m2, o2, t3 } n3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m3, k3, p2, o2, m2, t3 } p4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o4, f4 , m8, n8, k9, s3, r3, t4 } o4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p4, m4, s3, r3, k3, t4 } m4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o4, n4, k3, r3, m2, x, f, t4 } f4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p4, s4, m8, n8, k8, t4 } s4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f4, r4, p5, o5, m7, k8, n8, t4 } r4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s4, k4, p5, o5, m5, t4 } k4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n4, r4, g, f, p6, m5, o5, t4 } n4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m4, k4, x, f, g, t4 } p5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f5, o5, s4, r4, k8, m7, n7, t5 } o5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p5, m5, s4, r4, k4, t5 } m5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n5, o5, k4, r4, g, p6, f6, t5 } f5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p5, s5, m7, n7, k7, t5 } s5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f5, r5, k7, n7, m9, p3, o3, t5 } r5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k5, s5, p3, o3, m3, t5 } k5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n5, r5, s6, f6, p2, m3, o3, t5 } n5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m5, k5, p6, f6, s6, t5 } p6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f6, 06, g, I, k4, m5, n5, t6 }

06 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m6, p6, g, I, i, t6 } m6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n6, 06, i, I, s8, p7, f7, t6 } f6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p6, s6, m5, n5, k5, t6 } s6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f6, r6, k5, n5, m3, p2, y2, t6 } r6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s6, k6, p2, y2, s2, t6 } k6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n6, r6, s7, f7, p9, s2, y2, t6 } n6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m6, k6, p7, f7, s7, t6 } p7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f7, o7, s8, r8, i, m6, n6, t7 } o7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p7, m7, s8, r8, k8, t7 } m7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o7, n7, k8, r8, s4, p5, f5, t7 } f7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p7, s7, m6, n6, k6, t7 } s7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f7, r7, k6, n6, s2, p9, o9, t7 } r7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s7, k7, p9, o9, m9, t7 } k7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n7, r7, m9, o9, p3, s5, f5, t7 } n7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m7, k7, p5, f5, s5, t7 } p8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f8, 08, s9, r9, k2, z, h, t8 }

08 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p8, m8, s9, r9, k9, t8 } m8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 08, n8, k9, r9, s3, p4, f4, t8 } f8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p8, s8, z, h, i, t8 } s8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f8, r8, i, h, m6, p7, o7, t8 } r8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s8, k8, p7, o7, m7, t8 } k8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r8, n8, m7, o7, p5, s4, f4, t8 } n8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m8, k8, p4, f4, s4, t8 } p9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f9, o9, s2, r2, k6, s7, r7, t9 } o9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m9, p9, s7, r7, k7, t9 } m9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n9, o9, p3, f3, s5, k7, r7, t9 } f9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p9, s9, s2, r2, k2, t9 } s9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f9, r9, k2, r2, z, p8, 08, t9 } r9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k9, s9, p8, m8, 08, p8, t9 } k9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n9, r9, m8, 08, p4, s3, f3, t9 } t6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p6, 06, m6, f6, n6, s6, r6, k6 } t7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p7, o7, m7, f7, n7, s7, r7, k7 } t8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p8, 08, m8, f8, n8, s8, r8, k8 } t9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p9, o9, m9, f9, n9, s9, r9, k9 } xl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { yl , fl, ml2, nl2, kl3 ,ml4, ol4, tl } yl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { xl, zl, ml2, nl2, kl2, tl } zl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { yl, hl, kl2, nl2, sl9, pl8, fl8, tl } fl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { xl, gl, ml4, nl4, kl4, tl } hl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { zl, il, pl8, fl8, sl8, tl } gl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl, 11, kl4, nl4, ml5, pl6, 016, tl } 11 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { gl, il, pl6, 016, ml6, tl } il belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 11, hl, ml6, 016, pl7, sl8, fl8, tl } pl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 012, yl2, ml3, nl3, kl5, sl6, rl6, tl2 } yl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { pl2, sl2, sl6, rl6, kl6, tl2 } S12 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { rl2, yl2, pl9, fl9, sl7, kl6, rl6, tl2 } 012 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl2, ml2, ml3, nl3, kl3, tl2 } rl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl2, kl2, pl9, fl9, sl9, tl2 } ml2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { ol2, nl2, kl3, nl3, ml4, xl, yl, tl2 } nl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml2, kl2, xl, yl, zl, tl2 } kl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl2, rl2, zl, yl, pl8, sl9, fl9, tl2 } pl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl3, 013, ml9, nl9, kl7, sl5, rl5, tl3 } 013 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl3, ml3, sl5, rl5, kl5, tl3 } ml3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { 013, nl3, kl5, rl5, sl6, pl2, 012, tl3 } fl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl3, sl3, ml9, nl9, kl9, tl3 }

513 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl3, rl3, kl9, nl9, ml8, pl4, 014, tl3 } rl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl3, kl3, pl4, 014, ml4, tl3 } kl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { rl3, nl3, ml4, 014, xl, ml2, 012, tl3 } nl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml3, kl3, pl2, 012, ml2, tl3 } pl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 014, fl4 , ml8, nl8, kl9, sl3, rl3, tl4 } 014 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl4, ml4, sl3, rl3, kl3, tl4 } ml4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { 014, nl4, kl3, rl3, ml2, xl, fl, tl4 } fl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl4, sl4, ml8, nl8, kl8, tl4 }

514 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl4, rl4, pl5, 015, ml7, kl8, nl8, tl4 } rl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl4, kl4, pl5, 015, ml5, tl4 } kl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl4, rl4, gl, fl, pl6, ml5, 015, tl4 } nl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml4, kl4, xl, fl, gl, tl4 } pl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl5, 015, sl4, rl4, kl8, ml7, nl7, tl5 } 015 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl5, ml5, sl4, rl4, kl4, tl5 } ml5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl5, 015, kl4, rl4, gl, pl6, fl6, tl5 } fl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl5, sl5, ml7, nl7, kl7, tl5 }

515 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl5, rl5, kl7, nl7, ml9, pl3, 013, tl5 } rl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { kl5, sl5, pl3, 013, ml3, tl5 } kl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl5, rl5, sl6, fl6, pl2, ml3, 013, tl5 } nl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml5, kl5, pl6, fl6, sl6, tl5 } pl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl6, 016, gl, 11, kl4, ml5, nl5, tl6 } 016 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml6, pl6, gl, 11, il, tl6 } ml6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl6, 016, il, 11, sl8, pl7, fl7, tl6 } fl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl6, sl6, ml5, nl5, kl5, tl6 }

516 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl6, rl6, kl5, nl5, ml3, pl2, yl2, tl6 } rl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl6, kl6, pl2, yl2, sl2, tl6 } kl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl6, rl6, sl7, fl7, pl9, sl2, yl2, tl6 } nl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml6, kl6, pl7, fl7, sl7, tl6 } pl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl7, ol7, sl8, rl8, il, ml6, nl6, tl7 } 017 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl7, ml7, sl8, rl8, kl8, tl7 } ml7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { 017, nl7, kl8, rl8, sl4, pl5, fl5, tl7 } fl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl7, sl7, ml6, nl6, kl6, tl7 }

517 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl7, rl7, kl6, nl6, sl2, pl9, 019, tl7 } rl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl7, kl7, pl9, 019, ml9, tl7 } kl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { nl7, rl7, ml9, 019, pl3, sl5, fl5, tl7 } nl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml7, kl7, pl5, fl5, sl5, tl7 } pl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl8, 018, sl9, rl9, kl2, zl, hl, tl8 } 018 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl8, ml8, sl9, rl9, kl9, tl8 } ml8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { 018, nl8, kl9, rl9, sl3, pl4, fl4, tl8 } fl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl8, sl8, zl, hl, il, tl8 }

518 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl8, rl8, il, hl, ml6, pl7, 017, tl8 } rl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { sl8, kl8, pl7, 017, ml7, tl8 } kl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { rl8, nl8, ml7, 017, pl5, fl5, sl4, tl8 } nl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml8, kl8, pl4, fl4, sl4, tl8 } pl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl9, 019, sl2, rl2, kl6, sl7, rl7, tl9 } 019 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { ml9, pl9, sl7, rl7, kl7, tl9 } ml9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl9, 019, kl, rl7, sl5, pl3, fl3, tl9 } fl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl9, sl9, sl2, rl2, kl2, tl9 }

519 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { fl9, rl9, kl2, rl2, zl, pl8, 018, tl9 } rl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { kl9, sl9, pl8, 018, ml8, tl9 } kl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L}/ { nl9, rl9, ml8, 018, pl4, sl3, fl3, tl9 } nl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { kl9, ml9, pl3, fl3, sl3, tl9 } tl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { xl, yl, zl, fl, hl, gl, 11 ,11 } tl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl2, yl2, sl2, 012, rl2, ml2, nl2, kl2 } tl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl3, 013, ml3, fl3, nl3, sl3, rl3 ,kl3 } tl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl4, 014, ml4, fl4 ,nl4, sl4, rl4, kl4 } tl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl5, 015, ml5, fl5, nl5, sl5, rl5, kl5 } tl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl6, 016, ml6, fl6, nl6, sl6, rl6, kl6 } tl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl7, 017, ml7, fl7, nl7, sl7, rl7, kl7 } tl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl8, 018, ml8, fl8, nl8, sl8, rl8, kl8 } tl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { pl9, 019, ml9, fl9, nl9, sl9, rl9, kl9 } xl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { x, y, f, k3, m2, n2, m4, n4 } yl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { y, x, z, n2, m2, k2 } zl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { z, y, h, k2, n2, s9, p8, f8 } hl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { h, z, i, p8, f8, s8 } il belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { i, h, I, s8, f8, m6, 06, p6 } 11 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { I, g, i, 06, p6, m6 } gl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { g, f, I, k4, n4, p6, 06, m5 } fl belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f, x, g, n4, m4, k4 } pl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p2, y2, o2, m3, n3, k5, s6, r6 } yl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { y2, p2, s2, r6, s6, k6 }

S12 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s2, y2, r2, p9, f9, k6, r6, s7 } rl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r2, s2, k2, f9 , p9, s9 } kl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k2, r2, n2, s9, f9, p8, z, y } nl2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n2, m2, k2, x, y, z } ml2 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m2, o2, n2, k3, n3, x, y, m4 } 012 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o2, p2, m2, n3, m3, k3 } pl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p3, o3, f3, s5, r5, m9, n9, k7} 013 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p3, o3, m3, s5, r5, k5 } ml3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m3, o3, n3, p2, o2, s6, k5, r5 } nl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n3, m3, k3, p2, o2, m2 } kl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k3, n3, r3, m2, o2, x, m4, o4 } rl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r3, s3, k3, p4, o4, m4 }

513 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s3, f3, r3, p4, o4, m8, k9, n9 } fl3 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f3, p3, s3, m9, n9, k9 } pl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p4, o4, f4, s3, r3, m8, n8, k9 } 014 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o4, p4, m4, r3, s3, k3 } ml4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m4, o4, n4, k3, r3, x, f, m2} nl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n4, m4, k4, f, x, g } kl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k4, n4, r4, g, f, m5, o5, p6 } rl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r4, k4, s4, o5, m5, p5 }

514 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s4, f4, r4, p5, o5, k8, n8, m7 } fl4 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f4, p4, s4, n8, m8, k8 } pl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p5, f5, o5, s4, r4, m7, n7, k8 } 015 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o5, p5, m5 r4, s4, k4 } ml5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m5, o5, n5, k4, r4, p6, f6, g } nl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n5, m5, k5, f6, p6, s6 } kl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k5, n5, r5, s6, f6, m3, o3, p2 } rl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r5, k5, s5, o3, m3, p3 }

515 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s5, f5, r5, p3, o3, m9, k7, n7 } fl5 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f5, p5, s5, n7, k7, m7 } pl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p6, 06, f6, m5, n5, g, I, k4 } 016 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 06, m6, p6, g, I, i } ml6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m6, 06, n6, i, I, p7, f7, s8 } nl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n6, k6, m6, f7, p7, s7 } kl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k6, n6, r6, s7, f7, s2, y2, p9 } rl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r6, k6, s6, y2, p2, s2 }

516 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s6, f6, r6 , p2, y2 ,k5, n5, m3 } fl6 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f6, p6, s6, n5, m5, k5 } pl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p7, o7, f7, m6, n6, s8, r8, i } 017 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o7, m7, p7, r8, s8, k8 } ml7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m7, n7, o7, k8, r8, p5, f5, s4 } nl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n7, m7, k7, p5, f5, s5 } kl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k7, n7, r7, s5, f5, m9, o9, s5 } rl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r7, k7, s7, o9, m9, p9 }

517 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s7, f7, r7, k6, n6, p9, o9, s2 } fl7 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f7, p7, s7, n6, m6, k6 } pl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p8, f8, 08, s9, r9, z, h, k2 } 018 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { 08, m8, p8, k9, r9, s9 } ml8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m8, 08, n8, k9, r9, p4, f4, s3 } nl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n8, m8, k8, p4, f4, s4 } kl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k8, n8, r8, m7, o7, s4, f4, p5 } rl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r8, k8, s8, o7, p7, m7 }

518 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s8, f8, r8, p7, o7, i, h, m6 } fl8 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f8, p8, s8, h, i, z } pl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { p9, o9, f9, s2, r2, s7, r7, k6 }

019 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { o9, m9, p9, r7, k7, s7 } ml9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { m9, n9, o9, p3, f3, k7, r7, s5 } nl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { n9, k9, m9, f3, p3, s3 } kl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { k9, n9, r9, f3, s3, m8, 08, p4 } rl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { r9, k9, s9, 08, m8, p8 }

519 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { s9, f9, r9, p8, 08, k2, r2, z } fl9 belongs to {A,B,C,D,E,F,G,H,I,J,K,L} / { f9, p9, s9, r2, k2, s2 }

The sets of frequency bands associated to antennas at predetermined positions and/or comprising predetermined sectors fulfilling conditions for avoiding interferences, e.g., for serving radio devices within a geographical area, may be generated by a configuration software.

Fig. 25 shows an example of generating a set of frequency bands (also denoted as mosaic) by a configuration node, e.g., comprising the controller 200. The configuration node may comprise a terrestrial base station and/or may be part of a CN of the RAN.

The scheme generator starts at reference sign 2502 and prepares, at reference sign 2504, nine arrays (for a two-dimensional layer) or 19 arrays (for a three-dimensional configuration comprising at least two two-dimensional layers), e.g., corresponding to the number of aerial vehicles 100, with nine fields (e.g., corresponding to the number of sectors per aerial vehicle 100), which may take values from 0 to the number of frequency bands minus 1 at reference sign 2504. At reference sign 2506, the scheme generator proceeds to set all fields to zero and perform a flow B for current data, e.g., as detailed in Fig. 26. At reference sign 2508, the least significant bit is found, and at reference sign 2510 the field is increased, and the flow B (e.g., as detailed in Fig. 26) is performed again. At reference sign 2512, the scheme generator determines if the change field has a maximum value. If not, the scheme generator proceeds at reference sign 2514 to repeat the step 2510 of increasing the field. If the changed field has a maximum value, at reference sign 2516, the scheme generator proceeds to determine, at reference sign 2518, whether there is one or more significant field with no maximum value. If the answer is no, at reference sign 2534, flow B (e.g., as detailed in Fig. 26) is performed again, and at reference sign 2536 the generating of the set of frequency bands in the configuration node ends. If at reference sign 2520, one or more significant fields with no maximum value is found, at reference sign 2522, the nearest more significant field is found, and at reference sign 2524, if significant fields are zero-less, then they may be increased and the flow B (e.g., as detailed in Fig. 26) is performed again. At reference sign 2526, it is determined if the changed field has maximum value. If yes, at reference sign 2528, the scheme generator goes back to step 2508, If no, at reference sign 2530, the field is increased at reference sign 2510.

The number representation of a full pattern (e.g., an assignment of frequency bands to all aerial vehicles of a two-dimensional layer and/or of a three-dimensional constellation) may be incremented as long as the pattern does not fulfill the conditions. If the conditions are fulfilled, a valid assignment of frequency bands is found. The scheme generator operates from a least significant field by incrementing to more significant fields, and when having reached the most significant field, returning to the least significant field and repeatedly controlling if the conditions are fulfilled. If a valid assignment of frequency bands is found, the scheme generator may continue to find more, e.g., all, valid assignments of frequency bands.

Each field may be randomly assigned and conditions checked. Alternatively or in addition, a number of frequency bands may be represented by a number, where each frequency band A,B,C,D,E,F,G,H,I,J,K,L is represented by a digit additionally to the alphabetic character.

When solving for more than ten (e.g., twelve) digits, each row in a sub-constellation may be represented by an array where each field has a value representing the frequency band.

Alternatively or in addition, a set of nine arrays with nine fields each may be regarded as a number in a calculating system equal to a number of frequency bands used. A number of performing iterations may be up to (e.g., less than) or equal to a maximum value of the number plus 1.

Each (e.g., set of) value (e.g., comprising entries of the arrays) may be checked against the conditions for a two-dimensional layer deployment and/or a three-dimensional constellation deployment. Each (e.g., set of) value (e.g., comprising entries of the arrays) that fulfills the conditions may represent a valid mosaic for a sub-constellation for a predefined deployment type and/or using a predetermined number of frequency bands.

The configuration node (e.g., comprising controller 200) may work in an interactive mode and/or in a fast mode. In the interactive mode, all valid results may be shown to be chosen by aerial vehicle (e.g., drone) swarm operator. In the fast mode, the first valid result may be sent to the swarm (e.g., before and/or without determining further valid results). The validity may refer to the result (e.g., the values) satisfying the conditions.

Fig. 26 shows an example flowchart of checking the validity of a set of frequency bands (also denoted as sequence of frequency bands), e.g., as denoted by "flow B" in Fig. 25. At reference sign 2602, the check starts by, at reference sign 2604, determining if any neighboring sequence fields (e.g., corresponding to neighboring antennas and/or neighboring sectors being assigned the same frequency band) are equal. If yes, at reference sign 2608, the sequence is classified as invalid at reference sign 2620. If not, at reference sign 2606, it is checked if compared fields are equal in any condition. If yes, at reference sign 2614, the sequence is again classified as invalid. If no, at reference sign 2612, the sequence (also denoted as "current scheme" at reference sign 2616) is saved as valid. After the sequences has been saved as either valid at reference sign 2616 or as invalid at reference sign 2620, the check ends at reference sign 2618.

Fig. 27 shows an example flowchart of a configuration node (e.g., comprising the controller 200) sending validated results in interactive and/or fast mode. The configuration node start reference sign 2702 and checks at reference sign 2704, if the flow B (e.g., as described for Fig. 26, also denoted as "B check") has ended. If not, at reference sign 2706, the configuration node returns to the start. If yes, at reference sign 2708, the configuration node proceeds to determine if it operates in the interactive mode. If it does not operate in the interactive mode, at reference sign 2718, the configuration node proceeds to transmit the first valid result to the swarm of aerial vehicles at reference sign 2720 and ends its operation (e.g., regarding determining and/or transmitting valid results) at reference sign 2732. If the configuration node operates in interactive mode, at reference sign 2712, it proceeds to wait for all results for all flows B (e.g., as described for Fig, 26, also denoted as "B checks") at reference sign 2714 and then proceeds at reference sign 2716 to show the validated results on a desktop terminal to an operator of the swarm of aerial vehicles. At reference sign 2722, it is determined if the operator has chosen a valid set of frequency bands (also denoted as band scheme). If not, at reference signs 2726 and 2728, a loop of waiting for the operator's choice is performed. If yes at reference sign 2724, the chosen valid set of frequency bands is transmitted to the swarm of aerial vehicles at reference sign 2730, and the operation of the configuration node is ended at reference sign 2732. Any one of the sets of frequency bands (also denoted as schemes) that fulfill the conditions above may be chosen to represent the assignment of frequency bands (also denoted as frequency schematic) for the constellation of the swarm of aerial vehicles 100. The criteria of choosing a scheme may be based on, e.g., a transmission BLER and/ortransmission SINR at least in some cells of network (e.g., some sectors of the swarm of aerial vehicles 100). E.g., a too high BLER > 0.01% (configurable) may require a change of frequency band assignments, and/or a too low SINR < 99.99% (configurable) may require a change of frequency band assignments. A performance may be simulated or/and tested in the field (e.g., based on a radio device and/or UE score). Machine learning may be helpful to determine the best frequency band assignment (also denoted as frequency scheme) for foreseen, previously observed, and/or simulated conditions.

Figs. 28 and 29 show nine different sets of frequency bands for nine aerial vehicles 100 within an approximately square constellation. The number of frequency bands in each example in Figs. 28 and 29 is seven, denoted by letter A, B, C, D, E, F and G.

The sector assignments of among the aerial vehicles 100 may correspond to permutations with respect to the first sequence in Fig. 28. E.g., the assignment of frequency bands of the central vehicle 100 may take the positions of horizontal left (sequence 3), horizontal right (sequence 2), diagonal top-left (sequence 6), vertical top (sequence 4), diagonal top-right (sequence 5), diagonal bottom-left (sequence 7), vertical bottom (sequence 8) and diagonal bottom-right (sequence 9).

Sequence 1 in Fig. 28 corresponds the assignment of frequency bands displayed in Fig. 12 and, for an aerial vehicle 100 moving along trajectory 1402, in Fig. 14.

The aerial vehicle 100 (also denoted as vessel) with a planned trajectory (also denoted as path) may read navigation metrics. If a read azimuth of a neighboring aerial vehicle 100 changes, e.g., more than 22.5 + n-45 (wherein n is integer) degrees from the center of the analyzing aerial vehicle azimuth (0, north) and/or the distance is short enough to have interference of service, the aerial vehicle 100 (or the vessel) may densify radio power measurements from sectors. If a power of a previously opposite sector becomes weaker, a measurement of a power with regard to a new opposite sector is carried out (e.g., if non- orthogonal frequencies were used, interference could occur). The analyzing aerial vehicle 100 may check if the other aerial vehicle 100 is on a planned and/or spontaneous trajectory (also denoted as course). Alternatively or in addition, it may read and/or transmit its rank and the maximum served radio device priority. In normal circumstances, a first aerial vehicle 100 planning a trajectory change may have a follower (e.g., another aerial vehicle 100) that will take the place left but the first aerial vehicle 100. During a movement, handovers and/or chain handovers of radio devices (e.g., UEs) may occur between moving aerial vehicles 100. Alternatively or in addition, the aerial vehicles 100 may comprise mobile robots (also denoted as redundant mobile robots in case of taking over positions, e.g., in a chain).

During rotations, antennas may keep the azimuth as much as possible if mounted on an aerial vehicle 100 and/or a servo. Inter-sector handovers within the antenna system of an aerial vehicle 100 may occur when the antennas need to be rotated new course-wise to keep the overall sector-azimuths geometry and to not break antenna cables.

If the trajectory of another aerial vehicle 100 with a planned trajectory to move on the chosen position (also denoted as place), e.g. , based on a multiplication of rank and maximum served radio device priority of all aerial vehicles 100 claiming the same position, is performed, the aerial vehicle 100 with the bigger (or biggest, e.g., among neighboring aerial vehicles 100) result of the multiplication sends an RRC message suspend to radio devices (e.g., UEs) that have not been handed over to the aerial vehicle 100 behind (e.g., within a planned chain of changes of positions). The aerial vehicle 100 changes its frequency bands as required in new position (also denoted as area), and the next aerial vehicle 100 on the old position (also denoted as place) hands over non-suspended radio devices (e.g., UEs) and resumes suspended radio devices (e.g., UEs), e.g., after downloading a radio device context through the inter-aerial vehicle channel.

The aerial vehicle 100 with the smaller (or smallest, e.g., neighboring aerial vehicles 100) result of the multiplication disconnects from the RAN coverage (also denoted as network) sending a release message with a redirect to served radio devices (e.g., UEs) pointing to the cell of the neighbor aerial vehicle 100 with the strongest signal (e.g., ASU signal strengths in different wireless technologies). The aerial vehicle 100 repeats the checking actions in new position (also denoted as area) approached.

If two aerial vehicles 100 have an equal multiplication value, the aerial vehicle 100 with the better ASU (e.g., signal strengths in different wireless technologies) wins the competition for the new position.

In case the disconnected aerial vehicle 100 is again online near the same served radio device (e.g., UE), the UE may send an RRC resume message to reconnect to the RAN. If the reconnection is not performed on time, the radio device (e.g., UE) may reconnect to any other cell in the RAN, and/or to a new unlocked aerial vehicle 100 in the position (or place) of the previous aerial vehicle service. Fig. 30 shows a flowchart of managing substitutions of frequency bands (also denoted as carriers) in an aerial vehicle 100 performing a planned trajectory change (e.g., a planned change in position and/or a planned change in direction).

At reference sign 3002, the aerial vehicle 100 (e.g., a drone, RBS drone or RBS vessel) starts changing a planned trajectory. After checking its position relative to a central aerial vehicle 100 at reference sign 3004, it determines at reference sign 3006 if it passes the line of 22.5 + n-45 degrees, e.g., from north, relative to the central aerial vehicle 100. It not, at reference sign 3008, it returns to checking the position relative to the central aerial vehicle 100. If yes, at reference sign 3010, it proceeds to increase a density of radio measurements on sectors neighboring to the central aerial vehicle 100 at reference sign 3012. The density of radio measurements may comprise a number of measurements within a given time interval (e.g., performing measurements more frequently when increasing the density), a number of spatial directions for which measurements are performed, and/or a number of frequencies (e.g., subcarriers and/or frequency bands) for which measurements are performed. At reference sign 3014, it is determined if radio conditions of sectors on interfering positions are stronger than previously near opposite sectors. Previously near opposite sectors may refer to sectors, some frequency band assignments of which are (e.g., mutually) excluded by not fulfilling conditions, before a switch and/or change of (e.g., relative) positions aerial vehicles 100. Alternatively or in addition, new opposite sectors may be ones with frequency band assignments excluded by not fulfilling conditions after a reconfiguration (e.g., switch and/or change of (e.g., relative) positions aerial vehicles 100). If the radio conditions of sectors on interfering positions are stronger at reference sign 3016, it is further determined at reference sign 3018 if there are aerial vehicles 100 claiming to take the position. If yes at reference sign 3022, the aerial vehicle 100 gathers further aerial vehicles 100 claiming the same position, the same rank and/or the same maximum served radio device priority at reference sign 3022 and proceeds, at reference sign 3028, to multiply (in particular its own) rank and priority. At reference sign 3030, it determines if the result of (in particular its own) multiplication is higher than that of other aerial vehicles 100. If yes at reference sign 3032, the aerial vehicle 100 proceeds to send an RRC suspend message to radio devices (e.g., UEs it is serving) and substitutes frequency bands, followed by which it sends an RRC resume message to the radio devices at reference sign 3036.

If at the step 3014, the answer is no at reference sign 3024, and/or if at the step 3018, the answer is no at reference sign 3026, the aerial vehicle 100 (e.g., directly) proceeds to the step 3036. If at the step 3030, the answer is no at reference sign 3034, the aerial vehicle 100 instead sends a handover (HO) message with redirects to radio devices (e.g., UEs) and turns off its service. In any case, the steps taken by the aerial vehicle 100 for performing a planned change in trajectory (e.g., a planned change in position and/or direction of movement) ends at reference sign 3040.

Alternatively or in addition, an aerial vehicle 100 moving spontaneously with operational service provision may send an RRC suspend message to its served radio devices (e.g., UEs) each time it begins to interfere with any aerial vehicle 100 on a on planned trajectory. In such a situation, the spontaneously moving aerial vehicle 100 may send the RRC suspend message to its served radio devices (e.g., UEs) and turn off the service. If it starts a planned trajectory change (e.g., a change in position and/or a change in direction) later, it may turn on the service according to the scheme in the constellation (e.g., according to the assignment of frequency bands depending on the position of the aerial vehicle 100), e.g., after checking the multiplication of its rank and maximum (also denoted as highest) served radio device priority with other aerial vehicles 100 claiming the same planned positions (e.g., areas).

In case of radio devices (e.g., UEs) not supporting RRC suspend, the aerial vehicle 100 may reserve 250 milliseconds (ms) and send a handover message with redirect to radio devices (e.g., UEs) starting from the highest (e.g., radio device) in priority. The aerial device 100 may attempt to serve as much as possible (e.g., as many radio devices as possible) when decrementing the priority.

Fig. 31 shows a flowchart of managing substitutions of frequency bands (also denoted as carriers) in an aerial vehicle 100 (also denoted as RBS vessel) performing a spontaneous (e.g., different from a previously planned) trajectory change.

After starting a spontaneous change in trajectory at reference sign 3102, the aerial vehicle 100 checks, at reference sign 3104, its position relative to a central aerial vehicle 100 and proceeds, at reference sign 3106, to determine if passing the line of 22.5 + n-45 degree, e.g., from the north, towards the central aerial vehicle 100. If not at reference sign 3108, the aerial vehicle 100 returns to the step 3104. If yes at reference sign 3110, the aerial vehicle 100 increases, at reference sign 3112, a density of radio measurements on neighboring sectors, in particular to the central aerial vehicle 100. At reference sign 3114, the aerial vehicle 100 determines if radio conditions of sectors in interfering positions are stronger than previously, e.g., near opposite sectors. If yes at reference sign 3116, it is further determined at reference sign 3118 if there is any aerial vehicle 100 with a planned trajectory claiming to take the position. If this is not the case at reference sign 3120, at reference sign 3122, it is further determined if there is any aerial vehicle 100 on a spontaneously change trajectory that may interfere with any sector. If so at reference sign 3124, the aerial vehicle 100 gathers others aerial vehicles 100 that may interfere with any rank (e.g., per sector) and/or with any maximum served radio device priority at reference sign 3126 and proceeds, at reference sign 2134, to multiply (e.g., its own) rank and priority and, at reference sign 2136, to compare the result of the multiplication with that of other aerial vehicles 100. If its own results is higher at reference sign 3138, the aerial vehicle 100 proceeds at reference sign 3142 to send an RRC suspend message to radio devices, substitute frequency bands and transmit an RRC resume message to the radio devices.

If at step 3114 the result is no at reference sign 3128, and/or if at step 3122 the answer is no at reference sign 3132, the aerial vehicle 100 proceeds (e.g., directly) to the step 3142. It the result of step 3118 at reference sign 3130 is yes, and/or if the result of the step 3136 at reference sign 3140 is no, the aerial vehicle 100 instead proceeds to send a handover (HO) message with a redirect to the radio devices and turns of its service at reference sign 3144. In any case, the steps taken by the aerial vehicle 100 for performing a spontaneous change in trajectory ends at reference sign 3146.

The technique may be applied to uplink (UL), downlink (DL) or direct communications between radio devices, e.g., device-to-device (D2D) communications or sidelink (SL) communications.

Herein, any radio device may be a mobile or portable station and/or any radio device wirelessly connectable to a base station or RAN, or to another radio device. For example, the radio device may be a user equipment (UE), a device for machine-type communication (MTC) or a device for (e.g., narrowband) Internet of Things (loT). Two or more radio devices may be configured to wirelessly connect to each other, e.g., in an ad hoc radio network or via a 3GPP SL connection. Furthermore, any base station may be a station providing radio access, may be part of a radio access network (RAN) and/or may be a node connected to the RAN for controlling the radio access. For example, the base station may be an access point, for example a Wi-Fi access point, and/or an aerial vehicle.

Herein, whenever referring to noise or a signal-to-noise ratio (SNR), a corresponding step, feature or effect is also disclosed for noise and/or interference or a signal-to- interference-and-noise ratio (SINR), or vice versa.

Fig. 32 shows a schematic block diagram for an embodiment of the device 100. The device 100 comprises processing circuitry, e.g., one or more processors 3204 for performing the method 300 and memory 3206 coupled to the processors 3204. For example, the memory 3206 may be encoded with instructions that implement at least one of the modules 102, 104 and 106.

The one or more processors 3204 may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, microcode and/or encoded logic operable to provide, either alone or in conjunction with other components of the device 100, such as the memory 3206, transmitter functionality. For example, the one or more processors 3204 may execute instructions stored in the memory 3206. Such functionality may include providing various features and steps discussed herein, including any of the benefits disclosed herein. The expression "the device being operative to perform an action" may denote the device 100 being configured to perform the action.

As schematically illustrated in Fig. 32, the device 100 may be embodied by an aerial vehicle 3200, e.g., functioning as a transmitting base station. The aerial vehicle 3200 comprises a radio interface 3202 coupled to the device 100 for radio communication with one or more receiving stations, e.g., functioning as a receiving base station or a receiving UE.

Fig. 33 shows a schematic block diagram for an embodiment of the device 200. The device 200 comprises processing circuitry, e.g., one or more processors 3304 for performing the method 400 and memory 3306 coupled to the processors 3304. For example, the memory 3306 may be encoded with instructions that implement at least one of the modules 202 and 204.

The one or more processors 3304 may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, microcode and/or encoded logic operable to provide, either alone or in conjunction with other components of the device 200, such as the memory 3306, receiver functionality. For example, the one or more processors 3304 may execute instructions stored in the memory 3306. Such functionality may include providing various features and steps discussed herein, including any of the benefits disclosed herein. The expression "the device being operative to perform an action" may denote the device 200 being configured to perform the action.

As schematically illustrated in Fig. 33, the device 200 may be embodied by a controller 3300 of the swarm of aerial vehicles. The controller 3300 comprises a radio interface 3302 coupled to the device 200 for radio communication with one or more aerial vehicles, e.g., functioning as a transmitting base station or a transmitting UE.

With reference to Fig. 34, in accordance with an embodiment, a communication system 3400 includes a telecommunication network 3410, such as a 3GPP-type cellular network, which comprises an access network 3411, such as a radio access network, and a core network 3414. The access network 3411 comprises a plurality of base stations 3412a, 3412b, 3412c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 3413a, 3413b, 3413c. Each base station 3412a, 3412b, 3412c is connectable to the core network 3414 over a wired or wireless connection 3415. A first user equipment (UE) 3491 located in coverage area 3413c is configured to wirelessly connect to, or be paged by, the corresponding base station 3412c. A second UE 3492 in coverage area 3413a is wirelessly connectable to the corresponding base station 3412a. While a plurality of UEs 3491, 3492 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 3412.

The telecommunication network 3410 is itself connected to a host computer 3430, which may be embodied in the hardware and/or software of a standalone server, a cloud- implemented server, a distributed server or as processing resources in a server farm. The host computer 3430 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 3421, 3422 between the telecommunication network 3410 and the host computer 3430 may extend directly from the core network 3414 to the host computer 3430 or may go via an optional intermediate network 3420. The intermediate network 3420 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3420, if any, may be a backbone network or the Internet; in particular, the intermediate network 3420 may comprise two or more sub-networks (not shown).

The communication system 3400 of Fig. 34 as a whole enables connectivity between one of the connected UEs 3491, 3492 and the host computer 3430. The connectivity may be described as an over-the-top (OTT) connection 3450. The host computer 3430 and the connected UEs 3491, 3492 are configured to communicate data and/or signaling via the OTT connection 3450, using the access network 3411, the core network 3414, any intermediate network 3420 and possible further infrastructure (not shown) as intermediaries. The OTT connection 3450 may be transparent in the sense that the participating communication devices through which the OTT connection 3450 passes are unaware of routing of uplink and downlink communications. For example, a base station 3412 need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 3430 to be forwarded (e.g., handed over) to a connected UE 3491. Similarly, the base station 3412 need not be aware of the future routing of an outgoing uplink communication originating from the UE 3491 towards the host computer 3430. By virtue of the method 300 being performed by any one of the aerial vehicles 100 (acting as airborne base station 3412), and/or by virtue of the method 400 being performed by any controller 200 (acting as airborne and/or terrestrial base station 3412 and/or being deployed in the access network 3411, and/or generally being deployed in the telecommunications network 3419), the performance or range of the OTT connection 3450 can be improved, e.g., in terms of increased throughput and/or reduced latency. More specifically, the host computer 3430 may indicate to the RAN or the aerial vehicle 100 or the controller 200 (e.g., on an application layer) the QoS of the traffic. Beneficially, the OTT services may be delivered, e.g., in disaster affected areas and/or geographical areas without terrestrial base stations, where RAN coverage is provided by a swarm of aerial vehicles 100 with mounted base stations 3412.

Example implementations, in accordance with an embodiment of the UE, airborne and/or terrestrial base station (in particular the aerial vehicle 100 and/or controller 200) and host computer discussed in the preceding paragraphs, will now be described with reference to Fig. 35. In a communication system 3500, a host computer 3510 comprises hardware 3515 including a communication interface 3516 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 3500. The host computer 3510 further comprises processing circuitry 3518, which may have storage and/or processing capabilities. In particular, the processing circuitry 3518 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 3510 further comprises software 3511, which is stored in or accessible by the host computer 3510 and executable by the processing circuitry 3518. The software 3511 includes a host application 3512. The host application 3512 may be operable to provide a service to a remote user, such as a UE 3530 connecting via an OTT connection 3550 terminating at the UE 3530 and the host computer 3510. In providing the service to the remote user, the host application 3512 may provide user data, which is transmitted using the OTT connection 3550. The user data may depend on the location of the UE 3530. The user data may comprise auxiliary information or precision advertisements (also: ads) delivered to the UE 3530. The location may be reported by the UE 3530 to the host computer, e.g., using the OTT connection 3550, e.g., as provided by a swarm of aerial vehicles 100 and/or controller 200, and/or by the base station 3520, e.g., using a connection 3560. The base station 3520 may in particular comprise an airborne base station mounted on an aerial vehicle 100. The communication system 3500 further includes a base station 3520 provided in a telecommunication system and comprising hardware 3525 enabling it to communicate with the host computer 3510 and with the UE 3530. The hardware 3525 may include a communication interface 3526 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3500, as well as a radio interface 3527 for setting up and maintaining at least a wireless connection 3570 with a UE 3530 located in a coverage area (not shown in Fig. 35) served by the base station 3520. The communication interface 3526 may be configured to facilitate a connection 3560 to the host computer 3510. The connection 3560 may be direct, or it may pass through a core network (not shown in Fig. 35) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 3525 of the base station 3520 further includes processing circuitry 3528, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 3520 further has software 3521 stored internally or accessible via an external connection.

The communication system 3500 further includes the UE 3530 already referred to. Its hardware 3535 may include a radio interface 3537 configured to set up and maintain a wireless connection 3570 with a base station serving a coverage area in which the UE 3530 is currently located. The hardware 3535 of the UE 3530 further includes processing circuitry 3538, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 3530 further comprises software 3531, which is stored in or accessible by the UE 3530 and executable by the processing circuitry 3538. The software 3531 includes a client application 3532. The client application 3532 may be operable to provide a service to a human or non-human user via the UE 3530, with the support of the host computer 3510. In the host computer 3510, an executing host application 3512 may communicate with the executing client application 3532 via the OTT connection 3550 terminating at the UE 3530 and the host computer 3510. In providing the service to the user, the client application 3532 may receive request data from the host application 3512 and provide user data in response to the request data. The OTT connection 3550 may transfer both the request data and the user data. The client application 3532 may interact with the user to generate the user data that it provides.

It is noted that the host computer 3510, base station 3520 and UE 3530 illustrated in Fig. 35 may be identical to the host computer 3430, one of the base stations 3412a, 3412b, 3412c and one of the UEs 3491, 3492 of Fig. 34, respectively. This is to say, the inner workings of these entities may be as shown in Fig. 35, and, independently, the surrounding network topology may be that of Fig. 34.

In Fig. 35, the OTT connection 3550 has been drawn abstractly to illustrate the communication between the host computer 3510 and the UE 3530 via the base station 3520, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 3530 or from the service provider operating the host computer 3510, or both. While the OTT connection 3550 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection 3570 between the UE 3530 and the base station 3520 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 3530 using the OTT connection 3550, in which the wireless connection 3570 forms the last segment. More precisely, the teachings of these embodiments may reduce the latency and improve the data rate and thereby provide benefits such as better responsiveness and improved QoS.

A measurement procedure may be provided for the purpose of monitoring data rate, latency, QoS and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 3550 between the host computer 3510 and UE 3530, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 3550 may be implemented in the software 3511 of the host computer 3510 or in the software 3531 of the UE 3530, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 3550 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 3511, 3531 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 3550 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3520, and it may be unknown or imperceptible to the base station 3520. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer's 3510 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 3511, 3531 causes messages to be transmitted, in particular empty or "dummy" messages, using the OTT connection 3550 while it monitors propagation times, errors etc.

Fig. 36 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station (in particular airborne and/or mounted on an aerial vehicle 100) and a UE which may be those described with reference to Figs. 34 and 35. For simplicity of the present disclosure, only drawing references to Fig. 36 will be included in this paragraph. In a first step 3610 of the method, the host computer provides user data. In an optional substep 3611 of the first step 3610, the host computer provides the user data by executing a host application. In a second step 3620, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 3630, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 3640, the UE executes a client application associated with the host application executed by the host computer.

Fig. 37 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station (in particular airborne and/or mounted on an aerial vehicle 100) and a UE which may be those described with reference to Figs. 34 and 35. For simplicity of the present disclosure, only drawing references to Fig. 37 will be included in this paragraph. In a first step 3710 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 3720, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 3730, the UE receives the user data carried in the transmission.

As has become apparent from above description, at least some embodiments of the technique allow for a frequency saving placement and motion of aerial vehicles forming 2D and 3D swarms.

Alternatively or in addition, at least some embodiments of the technique enable self- healing RAN, and/or defining future techniques such as 6G, that may comprise limitless connectivity, trustworthy systems and/or cognitive networks. Mosaics of frequencies and constellations of aerial vehicles (e.g., mobile robots, vehicles, drones) may act as an interference antidote.

The aerial vehicles (e.g., embodying mobile base stations) within the swarm may be safeguarded against interference of other aerial vehicles (e.g., other mobile base stations) when a serving aerial vehicle makes a maneuver between (e.g., in terms of its geographical location) other serving aerial vehicles.

Besides of providing a network capable of being deployable in case of environmental catastrophes as emergency networks, the 3D constellations and assignments of frequency bands may also enable an operation of flying cars and/or drone cabs, where it is inevitable that some flying cars and/or drone cabs needs to provide wireless coverage for others.

An exemplary embodiment of the invention provides planar mobility (e.g., within a two- dimensional layer) of aerial vehicles bases on eight symmetrical sectors and one vertical directed below of the Aerial vehicle, using seven bands for one two-dimensional layer (also denoted as carpet network) and twelve bands for a three-dimensional constellation (also denoted as 3D network or cub) comprising multiple (e.g., at least two) two- dimensional layers, e.g., based on two interlaced planar sequences of frequency bands (e.g., repeated at every second two-dimensional layer).

Embodiments of the invention allow for a scaling of the architecture of the swarm of aerial vehicles in terms of planar scalable two-dimensional layers and associated frequency band assignments (also denoted as sequences of frequency bands), and/or in terms of vertically scalable blocks from interlaced two-dimensional layers and associated frequency band assignments (e.g., alternatingly repeated between vertically displayed two-dimensional layers).

The invention may in particular be implemented in connection to eNodeBs and/or gNodeBs of 4G, 5G and 6G developments of RANs, e.g., according to the 3GPP standards. Alternatively or in addition, open source software may be used, e.g., comprising bash, awk and/or sed.

Embodiments of the invention can provide energy improvements at the network level, e.g., at any aerial vehicles within the swarm and/or by saving energy at a terrestrial base station comprising a controller.

Many advantages of the present invention will be fully understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the units and devices without departing from the scope of the invention and/or without sacrificing all of its advantages. Since the invention can be varied in many ways, it will be recognized that the invention should be limited only by the scope of the following claims.

Claims

59 Claims

1. A method (300) of controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on a first aerial vehicle (100) and comprising one antenna per sector and the first aerial vehicle (100) moving within a swarm of aerial vehicles (100), wherein each aerial vehicle (100) in the swarm comprises a multi-sector antenna system, the method (300) comprising or initiating the steps of: determining (302) a trajectory of the first aerial vehicle (100) relative to other aerial vehicles (100) within the swarm; transmitting (304) an indication of the determined trajectory to at least one other aerial vehicle (100) within the swarm; and substituting (306) an assignment of frequency bands to the antennas of the multisector antenna system mounted on the first aerial vehicle (100) depending on the determined (302) trajectory while the first aerial vehicle (100) moves on the determined (302) trajectory, wherein each antenna of the multi-sector antenna system mounted on the first aerial vehicle (100) is assigned at least one frequency band.

2. The method (300) of claim 1, wherein the swarm of aerial vehicles (100) provides a RAN coverage for a terrestrial area of a predetermined shape.

3. The method (300) of claim l or 2, wherein the trajectory comprises a list of available and/or planned positions of the first aerial vehicle (100) as nodes on a grid.

4. The method (300) of any one of claims 1 to 3, wherein the multi-sector antenna system comprises at least one of four planar sectors, six planar sectors and eight planar sectors.

5. The method (300) of claim 4, wherein each planar sector is horizontally tilted towards the ground.

6. The method (300) of claim 5, wherein a tilt angle relative to a terrestrial plane is greater than thirty degrees and/or less than sixty degrees.

7. The method (300) of any one of claims 1 to 6, wherein the multi-sector antenna system further comprises one vertical sector. 60

8. The method (300) of any one of claims 1 to 7, wherein the plurality of frequency bands are mutually orthogonal and/or disjoint.

9. The method (300) of any one of claims 1 to 8, wherein the plurality of frequency bands comprises at least one of a sub-6 Giga Hertz, GHz, band and a millimeter, mm, wave band.

10. The method (300) of any one of claims 1 to 9, wherein the indication of the determined trajectory is transmitted using an inter-aerial vehicle link on at least one frequency band different from the plurality of frequency bands of the RAN provided by the multi-sector antenna systems of the aerial vehicles (100) within the swarm.

11. The method (300) of any one of claims 1 to 10, wherein the indication of the determined trajectory is transmitted using a relayed inter-aerial vehicle link, wherein the inter-aerial vehicle link is relayed through at least one of a terrestrial base station and a core network, CN, of a wireless communication system comprising the RAN.

12. The method (300) of any one of claims 1 to 11, wherein the swarm of aerial vehicles (100) is comprised in a two-dimensional layer, and wherein the determined trajectory of the first aerial vehicle (100) is comprised in the two-dimensional layer.

13. The method (300) of any one of claims 1 to 12, wherein the swarm of aerial vehicles (100) is comprised in a three-dimensional arrangement comprising at least two vertically displaced two-dimensional layers, and wherein the determined trajectory of the first aerial vehicle (100) is comprised within one of the two-dimensional layers.

14. The method (300) of claim 13, wherein all of the vertically displaced two- dimensional layers comprise a layer-specific horizontal position offset relative to a first two-dimensional layer.

15. The method (300) of claim 12 or 13, wherein the plurality of frequency bands of the vertically displaced two-dimensional layers comprises a layer-specific frequency offset relative to a first two-dimensional layer.

16. The method (300) of any one of claims 1 to 15, wherein the plurality of frequency bands comprises at least seven frequency bands and/or at most twelve frequency bands. 61

17. The method (300) of any one of claims 1 to 16, wherein the plurality of frequency bands comprises seven frequency bands for a swarm comprised in a two-dimensional layer.

18. The method (300) of any one of claims 1 to 17, wherein the plurality of frequency bands comprises twelve frequency bands for a swarm comprised in at least two vertically displayed two-dimensional layers.

19. The method (300) of any one of claims 1 to 18, wherein the method (300) is performed by a processing circuit of the first aerial vehicle (100).

20. The method (300) of any one of claims 1 to 19, wherein the first aerial vehicle (100) comprises memory and/or storage, and wherein the trajectory is determined (302) and/or the assignment of frequency bands is substituted (306) based on a stored map.

21. The method (300) of claim 20, wherein the planned trajectory and/or the planned position is comprised in a stored map.

22. The method (300) of any one of claims 1 to 21, wherein the determined trajectory further comprises a determined velocity for moving on the trajectory.

23. The method (300) of any one of claims 1 to 22, wherein the substituting (306) of the assignment of frequency bands is based on at least one measurement.

24. The method (300) of claim 23, wherein the at least one measurement comprises a distance of the first aerial vehicle (100) to at least one other aerial vehicle (100) within the swarm.

25. The method (300) of claim 23 or 24, wherein the at least one measurement comprises a signal strength and/or a signal quality of at least one other aerial vehicle (100) within the swarm.

26. The method (300) of any one of claims 1 to 25, wherein an initial assignment of frequency bands to the antennas is determined at deployment and/or at takeoff of the first aerial vehicle (100).

27. The method (300) of any one of claims I to 26, wherein the assignment of frequency bands is substituted (306) during a service of the first aerial vehicle (100) within the swarm of aerial vehicle (100). 62

28. The method (300) of any one of claims 1 to 27, wherein the indication of the determined (302) trajectory is encrypted.

29. The method (300) of any one of claims 1 to 28, wherein the indication of the determined (302) trajectory is comprised in a hermetic code, and wherein the hermetic code is associated with the stored map.

30. The method (300) of any one of claims 1 to 29, comprising updating the stored map during the service of the aerial vehicle (100).

31. The method (300) of any one of claims 1 to 30, further comprising serving at least one radio device on the assigned frequency bands of the antennas of the first aerial vehicle (100).

32. The method (300) of any one of claims 1 to 31, further comprising suspending a connection to the at least one radio device based on the substituting (306) of the assignment of frequency bands.

33. The method (300) of claim 31 or 32, wherein the serving and/or the connection comprises a radio resource control, RRC, connection.

34. The method (300) of any one of claims 1 to 33, wherein the indication of the determined (302) trajectory is transmitted (304) periodically.

35. The method (300) of any one of claims 1 to 34 wherein the indication of the determined trajectory further comprises at least one of a rank of the first aerial vehicle (100), a maximum served radio device priority of the first aerial vehicle (100), and an indication if the determined (302) trajectory comprises a planned trajectory or a spontaneous trajectory.

36. The method (300) of any one of claims 1 to 35, further comprising receiving an indication from at least one of the other aerial vehicles (100) within the swarm.

37. The method (300) of claim 36, wherein the received indication comprises at least one of a rank of the at least one other aerial vehicle (100), a maximum served radio device priority of the at least one other aerial vehicle (100), and an indication of a determined trajectory of the at least one other aerial vehicle (100) within the swarm. 63

38. The method (300) of claim 37, further comprising ordering the aerial vehicles (100) within the swarm based on the indicated rank and/or on the indicated maximum served radio device priority.

39. The method (300) of claim 38, wherein the ordering is based on a product of the indicated rank and the indicated maximum served radio device priority.

40. The method (300) of any one of claims 1 to 39, further comprising initiating a handover procedure of at least one radio device served by the first aerial vehicle (100) in one of the frequency bands that is subject to the substituting (306).

41. The method (300) of any one of claims 38 to 40, wherein a higher ordered aerial vehicle (100) among at least two aerial vehicles (100) within the swarm sends a suspend message to the at least one radio device and/or wherein a lower ordered aerial vehicle (100) among at least two aerial vehicles (100) within the swarm disconnects from the radio device.

42. The method (300) of any one of claims 38 to 41, wherein for aerial vehicles (100) within the swarm having the same order based on the indicated rank and/or on the indicating maximum served radio device priority, the aerial vehicle (100) with the higher signal strength and/or the higher signal quality sends the suspend message.

43. The method (300) of any one of claims 1 to 42, wherein at least one of a bandwidth of at least one frequency band within the plurality of frequency bands, and total bandwidth of the plurality of frequency bands is changed during a service of the first aerial vehicle (100).

44. The method (300) of any one of claims 1 to 43, wherein the substituting (306) further comprises a cyclic permutation of the assignment of frequency bands of the antennas of the first aerial vehicle (100).

45. The method (300) of claim 44, wherein the substitution (306) is responsive to a rotation of the first aerial vehicle (100) around a vertical axis, and wherein a direction of the cyclic permutation is opposite to a direction of the rotation.

46. The method (300) of any one of claims 1 to 45, wherein the determining (302) of the trajectory comprises receiving the trajectory from a controller (200; 3500) of the swarm of aerial vehicles (100).

47. The method (300) of any one of claims 1 to 46, wherein the method (300) further comprises or initiates the step of: receiving the assignment of frequency bands from a controller (200) of the swarm of aerial vehicles (100).

48. The method (300) of claim 46 or47 in combination with claim 20, further comprising the steps of: receiving an update massage regarding the stored map from the controller (200); and updating the stored map responsive to the received update message.

49. The method (300) of any one of claims 46 to 48, wherein the controller (200) is a terrestrial base station.

50. A method (400) of controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on any one aerial vehicle (100) of a swarm of aerial vehicles (100), the multisector antenna system comprising one antenna per sector and each aerial vehicle (100) moving within the swarm of aerial vehicles (100), the method (400) comprising or initiating the steps of: determining (402) at least one of a trajectory of at least one aerial vehicle (100) relative to at least one other aerial vehicle (100) within the swarm and/or determining (402) an assignment of frequency bands to the antennas of the multi-sector antenna system of the at least one aerial vehicle (100) within the swarm; and transmitting (404) at least one of the determined (402) trajectory of the at least one aerial vehicle (100) and the determined (402) assignment of the frequency bands of the at least one aerial vehicle (100) to at least one aerial vehicle (100) within the swarm of aerial vehicles (100).

51. The method (400) of claim 50, wherein an initial assignment of frequency bands is random.

52. The method (400) of claim 51, wherein the initial assignment is subject to a constraint.

53. The method (400) of any one of claims claim 50 to 52, wherein the determining (402) of the assignment of frequency bands comprises determining a first assignment compatible with a determined (402) trajectory and with a constraint.

54. The method (400) of any one of claims 50 to 53, wherein the assignment of frequency bands depends on a signal quality and/or a signal strength.

55. The method (400) of claim 54, wherein the signal quality comprises at least one of a minimum signal quality for at least one or each aerial vehicle (100) within the swarm and an average signal quality, wherein the average is taken over a subset or all aerial vehicles (100) within the swarm.

56. The method (400) of claim 54 or 54, wherein the signal quality comprises at least one of a block error rate, BLER, a signal-to-noise ratio, SNR, and a signal-to-interference- and-noise ratio, SINR.

57. The method (400) of any one of claims 50 to 56, further comprising transmitting, from a controller (200) to at least one aerial vehicle (100) within the swarm, a map in relation to trajectories of at least one or each of the aerial vehicles (100) within the swarm.

58. The method (400) of any one of claims 50 to 57, wherein the determining (402) of the assignment of frequency bands is based on receiving an indication, from at least one aerial vehicle (100) within the swarm, of a trajectory determined at the at least one aerial vehicle (100).

59. The method (400) of any one of claims 50 to 50, wherein the method is performed by a terrestrial base station.

60. A computer program product comprising program code portions for performing the steps of any one of the claims 1 to 49 or 50 to 59 when the computer program product is executed on one or more computing devices (3404; 3504), optionally stored on a computer-readable recording medium (3406; 3506). 66

61. A device (100; 3400) for controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on a first aerial vehicle (100; 3400) and comprising one antenna per sector and the first aerial vehicle (100; 3400) moving within a swarm of aerial vehicles (100; 3400), wherein each aerial vehicle (100; 3400) in the swarm comprises a multi-sector antenna system, the device (100; 3400) configured to: determine a trajectory of the first aerial vehicle (100; 3400) relative to other aerial vehicles (100; 3400) within the swarm; transmit an indication of the determined trajectory to at least one other aerial vehicle (100; 3400) within the swarm; and substitute an assignment of frequency bands to the antennas of the multi-sector antenna system mounted on the first aerial vehicle (100; 3400) depending on the determined trajectory while the first aerial vehicle (100; 3400) moves on the determined trajectory, wherein each antenna of the multi-sector antenna system mounted on the first aerial vehicle (100; 3400) is assigned at least one frequency band.

62. The device (100; 3400) of claim 61, wherein the aerial vehicle (100; 3400) comprises at least one of a primary function and a secondary function within the swarm of aerial vehicles (100; 3400), wherein the primary function autonomously determines (302) the trajectory and/or substitutes (306) the assignment of frequency bands, and wherein the secondary function comprises receiving an indication of a trajectory and/or an assignment of frequency bands from at least one of the other aerial vehicles (100; 3400), the determining (302) of the trajectory and/or the substituting (306) of the frequency bands depending on the received indication.

63. The device (100; 3400) of claim 62, wherein, if the aerial vehicle (100; 3400) comprises the secondary function, a receiving of the assignment of frequency bands and/or of the trajectory from a controller (200) comprises receiving the assignment of frequency bands and/or of the trajectory from at least one of the other aerial vehicles (100; 3400) within the swarm comprising the primary function.

64. The device (100; 3400) of any one of claims 61 to 63, further configured to perform the steps of any one of claims 2 to 49. 67

65. A device (200; 3500) for controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on any one aerial vehicle (100; 3400) of a swarm of aerial vehicles (100; 3400), the multi-sector antenna system comprising one antenna per sector and each aerial vehicle (100; 3400) moving within the swarm of aerial vehicles (100; 3400), the device (200; 3500) configured to: determine at least one of a trajectory of at least one aerial vehicle (100; 3400) relative to at least one other aerial vehicle (100; 3400) within the swarm and/or determine an assignment of frequency bands to the antennas of the multi-sector antenna system of the at least one aerial vehicle (100; 3400) within the swarm; and transmit at least one of the determined trajectory of the at least one aerial vehicle (100; 3400) and the determined assignment of the frequency bands of the at least one aerial vehicle (100; 3400) to at least one aerial vehicle (100; 3400) within the swarm of aerial vehicles (100; 3400).

66. The device (200; 3500) of claim 65, further configured to perform the steps of any one of claims 51 to 59.

67. A device (100; 3400) for controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on a first aerial vehicle (100; 3400) and comprising one antenna per sector and the first aerial vehicle (100; 3400) moving within a swarm of aerial vehicles (100; 3400), wherein each aerial vehicle (100; 3400) in the swarm comprises a multi-sector antenna system, the device (100; 3400) comprising memory (3406) operable to store instructions and processing circuitry (3404) operable to execute the instructions, whereby the device (100; 3400) is operative to: determine a trajectory of the first aerial vehicle (100; 3400) relative to other aerial vehicles (100; 3400) within the swarm; transmit an indication of the determined trajectory to at least one other aerial vehicle (100; 3400) within the swarm; and substitute an assignment of frequency bands to the antennas of the multi-sector antenna system mounted on the first aerial vehicle (100; 3400) depending on the determined trajectory while the first aerial vehicle (100; 3400) moves on the determined trajectory, wherein each antenna of the multi-sector antenna system mounted on the first aerial vehicle (100; 3400) is assigned at least one frequency band. 68

68. The device (100; 3400) of claim 67, wherein the aerial vehicle (100; 3400) comprises at least one of a primary function and a secondary function within the swarm of aerial vehicles (100; 3400), wherein the primary function autonomously determines (302) the trajectory and/or substitutes (306) the assignment of frequency bands, and wherein the secondary function comprises receiving an indication of a trajectory and/or an assignment of frequency bands from at least one of the other aerial vehicles (100; 3400), the determining (302) of the trajectory and/or the substituting (306) of the frequency bands depending on the received indication.

69. The device (100; 3400) of claim 68, wherein, if the aerial vehicle (100) comprises the secondary function, a receiving of the assignment of frequency bands and/or of the trajectory from a controller (200) comprises receiving the assignment of frequency bands and/or of the trajectory from at least one of the other aerial vehicles (100) within the swarm comprising the primary function.

70. The device (100; 3400) of any one of claims 67 to 69, further configured to perform the steps of any one of claims 2 to 49.

71. A device (200; 3500) for controlling a plurality of frequency bands of a multi-sector antenna system of a radio access network, RAN, the multi-sector antenna system being mounted on any one aerial vehicle (100) of a swarm of aerial vehicles (100), the multisector antenna system comprising one antenna per sector and each aerial vehicle (100) moving within the swarm of aerial vehicles (100), the device (200; 3500) comprising memory (3506) operable to store instructions and processing circuitry (3504) operable to execute the instructions, whereby the device (200; 3500) is operative to: determine at least one of a trajectory of at least one aerial vehicle (100) relative to at least one other aerial vehicle (100) within the swarm and/or determine an assignment of frequency bands to the antennas of the multi-sector antenna system of the at least one aerial vehicle (100) within the swarm; and transmit at least one of the determined trajectory of the at least one aerial vehicle (100) and the determined assignment of the frequency bands of the at least one aerial vehicle (100) to at least one aerial vehicle (100) within the swarm of aerial vehicles (100).

72. The device (200; 3500) of claim 71, further operative to perform the steps of any one of claims 51 to 59. 69

73. An aerial vehicle (100; 200; 3200; 3300) configured to communicate with a radio device (3491; 3492; 3530), the aerial vehicle (100; 200; 3200; 3300) comprising a radio interface and processing circuitry configured to execute the steps of any one of claims 1 to 49 or 50 to 59.

74. A base station (200; 3300; 3412; 3412a; 3412b; 3412c; 3520) configured to communicate with a swarm of aerial vehicles (100; 3400), the base station (200; 3300; 3412; 3412a; 3412b; 3412c; 3520) comprising a radio interface and processing circuitry configured to execute the steps of any one of claims 50 to 59.

75. A communication system (3400; 3500) including a host computer (3430; 3510) comprising: processing circuitry (3518) configured to provide user data; and a communication interface (3516) configured to forward user data to a cellular or ad hoc radio network (1500; 3410; 3411) for transmission to a user equipment, UE (3491; 3492; 3530), wherein the UE (3491; 3492; 3530) comprises a radio interface (3537), wherein a processing circuitry (3204; 3304) of the cellular network (1500; 3410; 3411) is configured to execute the steps of any one of claims 1 to 49 or 50 to 59.

76. The communication system (3400; 3500) of claim 75, further including the UE (3491; 3492; 3530).

77. The communication system (3400; 3500) of claim 75 or 76, further including one or more aerial vehicles (100; 200; 3200; 3300).

78. The communication system (3400; 3500) of any one of claims 75 to 77, wherein the radio network (1500; 3410; 3411) further comprises a base station (3412; 3412a; 3412b; 3412c; 3520) or radio device functioning as a gateway configured to communicate with at least one of the one or more aerial vehicles (100; 200; 3200; 3300) and the UE (3491; 3492; 3530).

79. The communication system (3400; 3500) of any one of claims 75 to 78, wherein: the processing circuitry (3518) of the host computer (3430; 3510) is configured to execute a host application (3512), thereby providing the user data; and the processing circuitry (3538) of the UE (3491; 3492; 3530) is configured to execute a client application (3532) associated with the host application (3512).