Controlling beamforming for a non-terresterial network

Abstract

The present disclosure relates to a method of a device (300) of assisting a non- terrestrial network (200) to serve at least one wireless communication device (110), and a device (300) performing the method. The method comprises acquiring (S101) information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of the terrestrial network (100), creating (S102), based on the acquired information, beamforming control data specifying how beamforming should be performed by the non-terrestrial network (200) to serve said at least one wireless communication device (110) while complying with a quality criterion, and controlling (S103) the beamforming of the non- terrestrial network (200) for serving said at least one wireless communication device (110) based on the created beamforming control data.

Description

CONTROLLING BEAMFORMING FOR A NON-TERRESTERIAL NETWORK TECHNICAL FIELD

[0001] The present disclosure relates to a method of a device of assisting a nonterrestrial network to serve at least one wireless communication device, and a device performing the method. Further disclosed are computer programs and computer program products.BACKGROUND

[0002] In sixth generation (6G) wireless communication systems, non-terrestrial networks (NTNs) are expected to serve as a complement to terrestrial networks (TNs), for instance providing connectivity in areas where the TNs do not provide coverage. Examples of such areas are remote areas, where TN operators do not have a financial incentive to provide coverage, or areas where a TN is not available due to power outages or equipment malfunction. Recently, advances in rocket technology have allowed significant reductions in NTN launch costs, and further allowed less expensive procedures for setting satellites into orbit, thereby resulting in a significant increase in broadband capability. In addition, the satellites themselves are becoming both less expensive and more capable of providing broadband capability.

[0003] Still, the coverage and capacity of satellites is limited when compared to TNs. In the art, modern satellites providing broadband services have beam steering technology, which allows the satellites to focus their signals on a specific area and therefore provide targeted coverage and capacity.

[0004] Beam steering in NTN is a well-explored topic. However, the data used to control the beam steering originates from observations made by the NTN, such as satellite position and velocity (relative to a user device to be served on the ground), user location, atmospheric conditions and interference. This may result in inferior NTN beam steering, and there is thus room for improvement.SUMMARY

[0005] One objective is to solve, or at least mitigate, the problems in the art and thus to provide a method of assisting a non-terrestrial network to serve at least one wireless communication device.

[0006] This objective is attained in a first aspect by a method of a device of assisting a non-terrestrial network to serve at least one wireless communication device. The method comprises acquiring information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network, creating, based on the acquired information, beamforming control data specifying how beamforming should be performed by the non-terrestrial network to serve said at least one wireless communication device while complying with a quality criterion, and controlling the beamforming of the non-terrestrial network for serving said at least one wireless communication device based on the created beamforming control data.

[0007] This objective is attained in a second aspect by a device configured to assist a non-terrestrial network to serve at least one wireless communication device. The device comprises a processing unit and a memory, said memory containing instructions executable by said processing unit, whereby the device is operative to acquire information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network, create, based on the acquired information, beamforming control data specifying how beamforming should be performed by the non-terrestrial network to serve said at least one wireless communication device while complying with a quality criterion, and control the beamforming of the non-terrestrial network for serving said at least one wireless communication device based on the created beamforming control data.

[0008] Advantageously, with the beamforming control data created based on information indicating capability of the terrestrial network to serve the wireless communication device, the non-terrestrial network will have access to far more information for performing the beamforming towards the wireless communication device as compared to current systems and the non-terrestrial network will thus be able to provide far more efficient communication with the wireless communication device. By integrating information from the terrestrial network into the beam management in the non-terrestrial network, the no n-t er restrial network can provide an improved coverage and support the terrestrial network not only in cases of signal loss but also during high demand or malfunctions in the terrestrial network.Furthermore, resources in the non-terrestrial network maybe saved as unnecessary beam allocations can be avoided.

[0009] In an embodiment, the controlling of the beamforming of the nonterrestrial network for serving said at least one wireless communication device based on the created beamforming control data comprises providing the created beamforming control data to the non-terrestrial network with an instruction to apply the created beamforming control data upon serving said at least one wireless communication device.

[0010] In an embodiment, the information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network is received from the terrestrial network with a handover request for said at least one wireless communication device.

[0011] In an embodiment, the method further comprises providing the terrestrial network with an instruction to perform handover of said at least one wireless communication device to the non-terrestrial network.

[0012] In an embodiment, said information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network comprises characteristics of said at least one wireless communication device including one or more of historical and / or future traffic patterns, mobility patterns, demands, policies, handover history.

[0013] In an embodiment, said information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network comprises one or more of an indication of one or more wireless communication devices that the terrestrial network requests to handover to the non-terrestrial network, one or more wireless communication devices that the terrestrial network considers as candidates for handover to the non-terrestrial network, one or more wireless communication devices that the terrestrial network considers as candidates for handover to the nonterrestrial network should the load in the terrestrial network increase to a load threshold, one or more wireless communication devices being in vicinity of parts of the coverage area where coverage is below a coverage threshold or in vicinity to an edge of the coverage area, one or more wireless communication devices that of acertain type, class or category, one or more wireless communication devices with a certain type or certain types of subscription.

[0014] In an embodiment, said information indicating capability of the terrestrial network to serve said at least one wireless communication device in at least one selected coverage area of the terrestrial network comprises one or more of status of wireless channels and / or radio access equipment in the coverage area, geographical coverage and shape of the coverage area, cell related traffic or load information of the coverage area.

[0015] In an embodiment, the method further comprises acquiring information indicating capability of the non-terrestrial network to serve said at least one wireless communication device in said at least one selected coverage area of the terrestrial network, wherein the creating of the beamforming control data further takes into account said acquired information indicating capability of the non-terrestrial network to serve said at least one wireless communication device.

[0016] In an embodiment, said information indicates capability of the nonterrestrial network to serve said at least one wireless communication device comprises one or more of weather or atmospheric conditions, terrain type and elevation.

[0017] In an embodiment, said information indicating capability of the nonterrestrial network to serve said at least one wireless communication device comprises observations indicating demand in the terrestrial network, and / or temporary or permanent occlusions that may obstruct signals of the non-terrestrial network.

[0018] In an embodiment, said information indicating capability of the terrestrial network and / or the non-terrestrial network to serve said at least one wireless communication device is provided at multiple time instances.

[0019] In an embodiment, the created beamforming control data is configured to cause beamforming at the non-terrestrial network, the causing of the beamforming including on or more of steering and / or controlling beam(s) of a satellite in terms of their directions, widths and shapes, on / off status, and number of beams.

[0020] In an embodiment, the created beamforming control data is configured to include instructions to the non-terrestrial network to prioritize areas with highaggregated demand and / or with limited coverage and steer the satellite beam(s) to cover those areas upon executing the beamforming control data.

[0021] In an embodiment, the created beamforming control data is configured to cause beamforming for a plurality of satellites in the non-terrestrial network.

[0022] In an embodiment, the creating of the beamforming control data comprises training an artificial intelligence (Al) model with the acquired information, and subsequently supplying the trained Al model with further acquired information for having the trained Al model create the beamforming control data.

[0023] In an embodiment, the method further comprises receiving a reward from the non-terrestrial network indicating to the Al model a degree of success attained upon applying the beamforming control data at the non-terrestrial network.

[0024] In an embodiment, the method further comprises receiving a reward from the terrestrial network indicating to the Al model a degree of success attained upon applying the beamforming control data at the non-terrestrial network.

[0025] In an embodiment, the quality criterion to be complied with relates to quality of a service to be provided to said at least one wireless communication device.

[0026] In a third aspect, a computer program is provided comprising computerexecutable instructions for causing a device to perform steps recited in the method of the first aspect when the computer-executable instructions are executed on a processing unit included in the device.

[0027] In a fourth aspect, a computer program product is provided comprising a computer readable medium, the computer readable medium having the computer program according to the third aspect embodied thereon.

[0028] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / an / the element, apparatus, component, means, step, etc." are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Aspects and embodiments are now described, by way of example, with reference to the accompanying drawings, in which:

[0030] Figure 1 illustrates a prior art terrestrial communication network;

[0031] Figure 2 illustrates a prior art terrestrial communications network and a non-terrestrial communication network;

[0032] Figure 3 illustrates a device according to an embodiment configured to assist a non-terrestrial communication network in serving a wireless communication device handed over from a terrestrial communication network;

[0033] Figure 4 shows a signalling diagram illustrating a method according to an embodiment;

[0034] Figure 5 shows a signalling diagram illustrating a method according to an embodiment;

[0035] Figure 6 shows a signalling diagram illustrating a method according to an embodiment;

[0036] Figure 7 shows a signalling diagram in another view illustrating a method according to an embodiment;

[0037] Figure 8 shows a signalling diagram in another view illustrating a method according to an embodiment; and

[0038] Figure 9 shows a device according to an embodiment configured to assist a non-terrestrial communication network in serving a wireless communication device.DETAILED DESCRIPTION

[0039] The aspects of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown.

[0040] These aspects may, however, be embodied in many different forms and should not be construed as limiting; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and to fully convey the scope of all aspects of invention to those skilled in the art. Like numbers refer to like elements throughout the description.

[0041] Figure 1 illustrates a schematic illustration of a terrestrial communication network 100 (TN) in which embodiments may be implemented. In the communication network 100, a first set of devices no, in, 112 in the form of User Equipment (UE), e.g. smart phones, tablets, desktops, gaming consoles, connected vehicles, Internet-of-Things (loT) devices, etc., are served by a network node which in this example is embodied in the form of a first radio base station 116 (RBS), while a second set of UEs 113, 114, 115 are served by a network node in the form of a second RBS 117. The first RBS 116 and the second RBS 117 are capable of communicating with each other via an Xn interface. In a 5G system, the radio base stations are commonly referred to as gNodeBs.

[0042] The network nodes 116, 117 may be composed of multiple physically separate components (e.g., a gNodeB component and a radio network controller (RNC) component, or a base transceiver station (BTS) component and a base station controller (BSC) component, etc.), which may each have their own respective components. In certain scenarios in which the network nodes 116, 117 comprise multiple separate components (e.g., BTS and BSC components), one or more of the separate components maybe shared among several network nodes. For example, a single RNC may control multiple gNodeBs. In such a scenario, each unique gNodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network nodes 116, 117 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory for different RATs) and some components may be reused (e.g., a same antenna may be shared by different RATs). The network nodes 116, 117 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network nodes 116, 117, for example Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), New Radio (NR), WiFi, Zigbee, Z-wave, Long Range Wide Area Network (LoRaWAN), Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network nodes 116, 117. The network nodes 116, 117 will in the following be exemplified in the form of RBSs.

[0043] Each RBS 116, 117 is connected to a core network 130, such has e.g., a 3rd Generation Partnership Project (3GPP) 5thgeneration core (5GC) network, and the 5GC network 130 is typically in its turn connected to the Internet, in this example illustrated with the 5GC network 130 connected to a cloud server 150.

[0044] Figure 2 illustrates that while one or more of the UEs 110-112 may be handed over from the first RBS 116 to the second RBS 117, and / or one or more of the UEs 113-115 may be handed over from the second RBS 117 to the first RBS 116, it may also be that in some deployments, a non-terrestrial communication network 200 (NTN) in the form of e.g. a satellite may be capable of serving one or more of the UEs, for instance in areas where none of the RBSs 116, 117 has capacity to serve the UEs, typically at the edges of the coverage areas of the RBSs 116, 117 (or outside these coverage areas).

[0045] As previously discussed, upon performing beamforming at an NTN 200 for serving a UE on ground, the data used to control the beamforming / beam steering originates from observations made by the NTN 200, which may be problematic.Beamforming and beam steering are herein used to refer to beam management in a broad sense, including creating, forming, refining, steering, and / or controlling beams and their patterns.

[0046] First, there are many different types of UEs, e.g. smart phones, tablets, desktops, gaming consoles, connected vehicles, Internet-of-Things (loT) devices, etc., and one UE may differ greatly from another (even in case of two UEs of the same type, such as two different smart phones) in terms of configuration, such as antenna set-up, processing power, data throughput capacity, etc.

[0047] Second, different subscription rules (e.g., policies) may apply to different users (and their UEs). For instance, one user may be assigned a higher priority than another user, as well as having different mobility and throughput patterns.

[0048] Third, NTN beam steering is performed on existing demand, without taking into account future demand. The NTN 200 may potentially try to predict future demand using e.g. a machine-learning (ML) model, but network traffic is generally stochastic and is in practice difficult to predict.

[0049] In embodiments, with reference to Figure 3, this is resolved by involving the TN 100 in providing data for the NTN 200 to decide how to perform beamsteering towards the UEs 110-115. Specifically, a logical entity 300 referred to as a Demand Matrix Calculator (DMCalc) is proposed. This entity extracts a spatial matrix of demand from the TN 100 that may be augmented with observations from the NTN 200.

[0050] In one embodiment, the DMCalc 300 uses this augmented map to predict demand, by training a neural network, and sends this information to the beam steering management function of the NTN 200. In another embodiment, optimizations may further include TN-initiated handover procedure for any UE that are deemed as risky to move outside of the coverage area 118 of the TN 100, or for any UE that is located in an area where the TN 100 is experiencing instabilities.

[0051] Figure 4 shows a signalling diagram illustrating a method performed by the DMCalc 300 for assisting the NTN 200 in serving one or more of the UEs 110-115.

[0052] While the DMCalc 300 is illustrated in Figure 3 as a stand-alone entity, the DMCalc 300 is a logical node and can reside e.g. in the TN 100 (for instance in one of the RBSs 113, 117 or in the core network 130), in a satellite control centre, in the NTN 200, or be operated as a third-party node, e.g, hosted as a cloud service at a hyperscale cloud provider.

[0053] Thus, as shown in Figure 4, the TN 100 (for instance either the first RBS 113, the second RBS 117 or both) provides information indicating capability of the TN 100 to serve one or more of the UEs in at least one selected coverage area 118 of the TN 100 to the DMcalc 300 in S101.

[0054] For instance, assuming that the first UE 110 moves towards an edge of the coverage area 118 provided by the first RBS 116 currently serving TN 100 (and subsequently potentially even moving out of the coverage area 118), as illustrated by means of the dotted arrow in Figure 3. If in this example there is no neighbouring RBS to which the first UE 110 can be handed over (other than the second RBS 117 which cannot provide coverage to the UE 110 moving in the indicated direction), the first RBS 116 may send information accordingly that it cannot serve the first UE 110 if the first UE 110 maintains its movement in the indicated direction. The information sent from the RBS 116 to the DMCalc 300 in S101 may for instance comprise a handover request including an identifier of the first UE 110, an indication of a qualityof service (QoS) to be expected by a user of the UE no in accordance with a current policy agreement and geographic coordinates of the UE too.

[0055] Upon receiving information indicating capability to serve in S101 (e.g. in a handover request as shown in Figure 4), the DMCalc 300 creates in S102, based on the acquired information, beamforming control data specifying how beamforming should be performed by the NTN 200 to serve the first UE 110 while complying with a quality criterion. The quality criterion may in this embodiment be stipulated by the expected QoS provided in S101. In other words, the satellite of the NTN 200 should aim at providing beamforming upon communication with the first UE 110 such that the expected QoS is delivered.

[0056] The created beamforming control data is sent to the NTN 200 in S103, wherein the NTN 300 performs the beamforming in step S104 towards the first UE no in accordance with the created beamforming control data received in S103. Thus, the DMCalc 300 effectively controls, with the created beamforming control data sent in S103, the beamforming performed by the NTN 200 towards the first UE 110.

[0057] Hence, the beamforming control data will in this example generally stipulate that the NTN 200 should perform beamforming towards the first UE 110 as identified by the UE ID and located at the provided geographical coordinates such that the expected QoS is achieved. This may or may not include specific instructions on e.g. how to steer an antenna of the satellites of the NTN 200, but it may alternatively be that the NTN 200 itself determines how the antenna should be steered towards the UE 110.

[0058] Advantageously, the NTN 200 will have access to far more information for performing the beamforming towards the UE 110 as compared to current systems and the NTN 200 will thus be able to provide far more efficient communication with the UE 110.

[0059] Figure 5 illustrates a further embodiment, where in addition to acquiring information as to the capability of the TN 100 to serve the first UE 110, the DMCalc 300 further acquires in Sioia information from the NTN 200 regarding capability of the NTN 200 to serve the first UE 110 in case the first UE 110 is handed over to the NTN 200.

[0060] For instance, this information may include satellite observations such as weather or atmospheric conditions that may affect coverage, visual observations that upon analysis can indicate potential “hotspots” of network demand but also reveal temporary or permanent occlusions that may obstruct satellite signals, and other geographical observations such as terrain type, elevation, etc.

[0061] Advantageously, this will facilitate the creation of the beamforming control data at the DMCalc in S102.

[0062] For instance, assuming that the NTN 200 indicates with the information in Sioia that the first UE 110 is moving into a forest or building, it may be that the created beamforming control data will indicate a higher transmission power to be applied by the NTN 200 upon performing the beamforming in S104 for sending data to the first UE 110, since otherwise it may not be possible to provide the expected QoS. In another scenario, it may be that the expected QoS to be complied with is relatively low, having as an effect that the transmission power may be lowered at the NTN 200, even if the UE 100 is moving into a forest or building. Nevertheless, with the created beamforming control data, an informed decision is being taken.

[0063] In an alternative, it may be that the DMCalc 300 concludes from the NTN information acquired in Sioia that this particular NTN 200 is not a good candidate to which the first UE 110 should be handed over, and thus turn to another NTN (not shown) for investigating a potential handover of the first UE 110.

[0064] While in the above exemplified embodiment, data pertaining to a single UE 110 is sent from the TN 100 to the DMCalc 300 for creation of the beamforming control data to be applied by the NTN 200 for communicating with the UE 110.However, in practice, the TN 100 can send data of a large number of UEs based on which the DMCalc 300 creates the beamforming control data to subsequently be applied by the NTN 200. This created beamforming data will thus consider the NTN 200 communicating with said large number of UEs. In such a scenario, the quality criterion to be complied with may include distinguishing between different UEs based on service level agreements (SLAs), where e.g. one group of UEs are prioritized before another group on terms of QoS to be provided. This may further include redirecting beams of neighbouring satellites forming part of the NTN 200 towards a prioritized area or even prioritized UEs. The created beamforming control data may thus bestructured in matrix form where matrix elements represent different geographical regions and / or different UEs.

[0065] Advantageously, by taking into account TN-supplied information as regards the capability of the TN 100 to serve the UEs, and potentially any UE characteristics, the DMCalc 300 can adjust beam steering at the NTN 200 and more efficiently set up a handover strategy. This further enables for mobile network operators to make the NTN 200 aware of information in the form of SLAs and other service policies.

[0066] Further advantageous is that the NTN 200 can serve as a backup coverage provider for the TN 100 to serve the UEs 110-115, not only in cases of signal loss (LoS), e.g. if one or more of the UEs 110-115 move out of the coverage area 118 of the TN 100, but also when the TN 100 reaches capacity limits or encounters malfunctions.

[0067] Now, the information provided to the DMCalc 300 by the TN 100 in S101 of Figures 4 and 5 may comprise many different types of information, which ultimately will be reflected in the beamforming control data created by the DMCalc 300 in S102 being provided to the NTN 200 in S103 with an instruction to apply S104 the beamforming control data upon serving one or more of the UEs 110-115.

[0068] In embodiments, the information provided by the TN 100 in S101 may include one or more of:- characteristics of the UE(s) 110-115 in the coverage area 118, which information may indicate traffic patterns, mobility patterns and policies of the UEs 110-115, where (a) the traffic patterns may be quantified e.g. as historical throughput or historical or future traffic demand (per UE or group of UEs) in uplink and downlink, (b) mobility patterns may indicate the handover history of a UE, for example to which RBS 116, 117 the UE was handed over to and how much time the UE spent being served by a specific RBS. All observations can be expressed as individual observations or using some statistical metric (e.g., average and standard deviation);- UE(s) the TN 100 wish to handover to the NTN 200;- UE(s) the TN 100 potentially may consider handing over to the NTN 200;- UE(s) that may be candidates for being handed over to the NTN 200, should the total TN load increase up to a load threshold;- UE(s) close to known holes in the coverage area 118 of the TN 100 or being close to edges of the TN coverage area 118;- UE(s) of a certain type / class / category; and / or- UE(s) with a certain type or certain types of subscription; or any combination or subset of the above.

[0069] In further embodiments, the information provided by the TN 100 in S101 may include one or more of:- status of the wireless channels in the coverage area 118, which information may be quantified using pilot signal observations from one or more UEs, e.g., Reference Signal Received Power (RSRP) Layer 3 observations from Radio Resource Control / Radio Resource Management (RRC / RRM) measurement reports (e.g. MeasurementReport messages or Channel Quality Information (CQI) from Channel State Information Reference Signal (CSI-RS) requests (Layer 1)), and other sources of information could for example be block error rate (BLER), measuring proportion of data blocks received with errors, and bit error rate (BER), a similar metric that measures the rate of errors in the bits received compared to the bits transmitted;- status of radio access equipment in the area, where specifically of interest in this category is whether some part of the RBSs 116, 117 is malfunctioning or is overloaded in such a way that it impairs normal operation, and there are several metrics that can be used here, for example frequency of triggered alarms or system logs and their criticality rating and voltage fluctuations of power supplied, that may indicate issues with the electrical grid;- geographical coverage and shape of the area 118, where one way to record this information e.g. would be to use a so-called bounding box with two sets of <latitude, longitude> coordinates in case the area 118 is rectangular, or additional sets of <latitude, longitude> pairs in case the area 118 has another shape, or a more compact way to roughly indicate the area may be to use one <latitude, longitude> coordinate pair representing the centre of a circle, and one value representing the circle’s radius;- cell related traffic or load information, e.g. the load in the cell or area 118 and / or margin to overload, aggregated traffic characteristics (for the cell or restricted to aggregated traffic characteristics pertaining to a set of UE(s) according to the restrictions listed above), total traffic demand (for the cell or restricted to traffic demand pertaining to a set of UE(s) according to the restrictions listed above), wherein the information may be provided for a set of cells, or a geographical area, rather than a single cell.

[0070] The information can be provided in multiple time instances, i.e. a first piece of information is provided for time instant ti, while a second piece of information is provided for time instant t2, and a third piece of information is provided for time instant t3, and so on. This may advantageously be useful for an artificial intelligence (Al) model to predict a future network state based on information gathered at different time instances.

[0071] Similarly, the information provided to the DMCalc 300 by the NTN 200 in Sioia of Figure 5 may comprise many different types of information, which ultimately will be reflected in the beamforming control data created by the DMCalc 300 in S102 and provided to the NTN 200 in S103 for application by the NTN 200 in S104 upon communicating with one or more of the UEs 110-115.

[0072] In embodiments, the information provided by the NTN 200 in Sioia may include one or more of:- satellite observations such as atmospheric conditions, that may affect coverage, heat signatures and visual observations that upon analysis can indicate potential “hotspots” of network demand but also reveal temporary or permanent occlusions that may obstruct satellite signals, and other geographical observations such as terrain type, elevation, etc. As is the case with the previously described TN observations, this information may be arranged in different elements.

[0073] Thus, the DMCalc 300 acquires in S101 and optionally in Sioia information from the TN 100 and the NTN 200, respectively, and creates the beamforming control data in S102 based on the sets of information attained in S101 and Sioia, and thereafter the created beamforming control data is sent to the NTN200 in S103 for controlling the beamforming applied by the NTN 200 in S104 upon communicating with one or more of the UEs 110-115.

[0074] In embodiments, the DMCalc 300 may in S102 (or earlier) train an artificial neural network (ANN) or other artificial intelligence (Al) model by supplying the information acquired in S101 and optionally in Sioia to the model in order to have the model output the created beamforming control data. Subsequently, in an inference phase, upon receiving any new information in S101 and Sioia, said new information is input to the trained model for creating the beamforming control data as output to be supplied to the TN 200 in S103 such that the NTN 200 can control the beamforming upon communicating with one or more of the UEs 110-115. As mentioned, the created beamforming control data may be structured as one or matrices where the elements represent different geographical areas, different UEs, different demands to be captured for different time instances, etc.

[0075] The training phase may be performed continuously throughout the lifetime of the network and can be triggered upon detection of model performance degradation from the DMCalc 300 or another node (also known as “model drift”), or can be done proactively, e.g., on a timely basis such as fixed period. In an example, the training phase may rely on a feedback-based mechanism such that online learning and reinforcement learning type of algorithms can be applied.

[0076] In some embodiments, the DMCalc 300 may produce longer-term predictions, e.g. through learning regular or systematic patterns of time of day changes of demand (or broken down to different input types) and / or day of week patterns, and possibly patterns related to public holidays.

[0077] Thus, the trained model may subsequently be utilized in S102 by the DMCalc 300 either triggered on a timely basis (e.g., periodically), or based on a specific event (e.g., the TN 100 detecting potential service outage in the area 118), to provide updated beamforming control data to the NTN 200 in S103, in response to which the NTN 200 for instance may steer its beam(s) to cover certain area(s) based on predicted demand as set out by the updated beamforming control data.

[0078] In an optional embodiment, illustrated in 8103a of Figure 6, the DMCalc 300 may also inform the TN 100 that the TN 100 should (in response to the handoverrequest sent in Slot), initiate handover of the UE no to the NTN 200 (or whichever NTN the DMCalc 200 selects for the handover).

[0079] As illustrated in Figure 7, in an embodiment, based on the information provided to the DMCalc 300 by the TN 100 in S101 and optionally the information provided to the DMCalc 300 by the NTN 200 in Sioia, the DMCalc 300 creates the beamforming control data in S102 and sends the beamforming control data to the NTN 200, wherein the NTN 200 applies the beamforming control data for controlling the beamforming in S104 upon communicating with the UE 110 having moved out of the coverage area 118 of the TN 100 and thus having been handed over to the NTN 200.

[0080] In this embodiment, the beamforming control data created by the DMCalc 300 in S102 and supplied to the NTN 200 in S103 comprises control data being input to a physical or logical entity of the NTN 200, such as e.g. a processing entity 202 of the satellite 201, which steers and / or controls the satellite’s beam(s), e.g. in terms of their directions, their widths and shapes (e.g. the size and shape of the beams’ footprints on the Earth, controlled by antenna 203 and / or antenna element weights), their on / off status, the number of beams, etc. The beamforming control data may hence control the creation / formation of a beam and / or its beam pattern. This beam steering control entity may be an entity on the ground, e.g. residing in a satellite control centre or in one of the RBSs 116, 117 or may be an entity in the satellite 201 (such as said processing entity 202) or may be a combination of an entity in a satellite and an entity on the ground. Based at least partly on the output from the DMCalc 300, the beam steering control entity may e.g. change or adapt the direction, width, shape of one or more beam(s) and / or the number of satellite beams as well as whether specific beams are turned on or off at certain times (e.g. on / off or active / inactive schedules).

[0081] Again with refence to Figure 7, the created beamforming control data supplied to the NTN 200 in S103 may in an embodiment included instructions to the beam steering control entity to prioritize areas with high aggregated demand and steer the satellite beam(s) to cover those areas upon executing the beamforming control data in S104 to communicate with one or more of the UEs in S105 (in this example communicating with the first UE 110). This may comprise only covering those areas, while other areas are left without coverage. As another option, all areaspotentially reachable by the satellite’s beam(s) (or at least more areas than the satellite can cover simultaneously) will receive coverage on a time-sharing basis (e.g. a first set of areas is covered during a certain time period, a second set of areas is covered during a subsequent time period, etc.), wherein the time shares / periods different areas get coverage in vary depending on the aggregated demand of the areas (e.g. longer or more frequent coverage time periods the higher the demand).

[0082] In another embodiment, e.g. as a first level of area coverage prioritization, the beam steering control entity (embodied for instance by the processing entity 202 of the satellite 201) prioritizes to provide coverage in areas where there is no TN coverage, i.e. outside of the coverage area 118, and / or areas in which input S101 from the TN 100 indicates that the TN 100 is overloaded or malfunctioning (or even not functioning at all). When this embodiment is combined with the preceding embodiment, the beam steering control entity 202 may for example first determine the areas where there is no or limited TN coverage and determine to only cover those areas, and among those areas, the beam steering control entity 202 could then prioritize areas with high aggregated demand as described in the preceding embodiment. In another example of how the embodiment may be combined with the preceding embodiment, the beam steering control entity 202 could first determine the areas where there is no TN coverage and determine to prioritize giving coverage to those areas, but to also provide coverage in the areas which have TN coverage (such as e.g. area 118), albeit with lower priority. To this end, the beam steering control entity 202 may give the areas without TN coverage a share of the coverage that is unproportionally large compared with the areas where there is TN coverage.

[0083] For instance, the average coverage time share for the areas without TN coverage maybe larger than the average coverage time share for the areas with TN coverage. As an example, if there are equally many areas with TN coverage as without TN coverage (and the combined size of the areas with TN coverage is equal to the combined size of the areas without TN coverage), the beam steering control entity 202 may give a share of the coverage (e.g. in time) to the areas without TN coverage which is greater than the share of the coverage given to the areas with TN coverage (e.g. a share greater than 50%). Then, among the areas without TN coverage the beam steering control entity 202 may prioritize areas with high aggregated demand as described in the preceding embodiment (e.g. provide longer or more frequentcoverage time periods to areas with higher demand than to areas with lower demand). Similarly, among the areas with TN coverage the beam steering control entity 202 may prioritize areas with high aggregated demand as described in the preceding embodiment (e.g. provide longer or more frequent coverage time periods to areas with higher demand than to areas with lower demand). As is understood, the actions taken by the beam steering control entity 202 are based on the beamforming control data.

[0084] As previously mentioned, the DMCalc 300 may consider further satellites (not shown) in the NTN 200 for performing the handover. For instance, when a constellation of satellites is used, each satellite can obtain beamforming control data related to its own area of coverage at a given time, and then these sets of beamforming control data can be exchanged among neighbouring satellites in the constellation, either through the ground network or via inter-satellite communication links. The satellites can then use the collected sets of beamforming control data to perform beam steering in a more coordinated manner; for example, a satellite can steer its beam in order to account for an area losing coverage because of the movement of another satellite that was currently covering the area.

[0085] Further, the coverage area of the TN 100 and the NTN 200 may be different in size. For instance, in NTN 200, satellites cover much larger geographical distances, which also means that when creating the beamforming control data in S102, several TN observations may be aggregated from information acquired in S101, which may correspond to a single NTN observation.

[0086] Moreover, there can be multiple TN and NTN observations accounting for different time durations. As is understood, a great amount of data may be acquired from different parts of the TN 100 in S101 and the NTN 200 in sioia to gather these observations based on which the beamforming control data is created by the DMCalc in S102, the acquired observations may account for a time duration rather than a single moment in time (e.g., 0-5, 5-10 and 10-15 seconds before current time). When combining information from the TN 100 and the NTN 200 to create the beamforming control data in S102, the time dimension may also need to be considered as information collection is not necessarily synchronized between the TN 100 and the NTN 200. Therefore, based on the above, the combining of the TN and NTNobservations typically need to take both spatial and temporal dimensions into account.

[0087] Figure 8 illustrates an embodiment where in the case an Al model is utilized for creating the beamforming control data in S102, the process for training the Al model may incorporate an exploration-exploitation algorithm, such as epsilon-greedy. The beamforming control data is then applied in the NTN 200 in S104, which provides feedback in the form of a reward function in S106. The reward indicates how successful application of the beamforming control data was upon communicating with the UE 110 in S105, for instance in terms of how well the expected QoS was complied with. Optionally, the beamforming control data can also be sent to the TN 100, which can produce its own reward e.g. reflecting a reduction in packet drop rate (due to avoiding the TN 100 being over-utilized), as indicated in S107. The rewards of S106 and S107 can be combined for a total reward (e.g., by averaging the two rewards). Once the rewards are received and aggregated, the DMCalc 300 can observe new data from the TN 100 and the NTN 200. The complete interaction <input, the beamforming control data, reward, new input> can be stored as an “experience” in a buffer.

[0088] After a few iterations, the DMCalc 300 can acquire random samples from its experience buffer and train its Al model.

[0089] Figure 9 illustrates a device 300 (referred to herein as DMCalc) configured to assist an NTN to serve one or more UEs according to an embodiment. The steps of the method performed by the DMCalc 300 are in practice performed by a processing unit 411 embodied in the form of one or more microprocessors arranged to execute a computer program 412 downloaded to a storage medium 413 associated with the microprocessor, such as a Random Access Memory (RAM), a Flash memory or a hard disk drive. The processing unit 411 is arranged to cause the DMCalc 300 to carry out the method according to embodiments when the appropriate computer program 412 comprising computer-executable instructions is downloaded to the storage medium 413 and executed by the processing unit 411. The storage medium 413 may also be a computer program product comprising the computer program 412. Alternatively, the computer program 412 may be transferred to the storage medium 413 by means of a suitable computer program product, such as a Digital Versatile Disc (DVD) or a memory stick. As a further alternative, the computer program 412 may bedownloaded to the storage medium 413 over a network. The processing unit 411 may alternatively be embodied in the form of a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a complex programmable logic device (CPLD), etc. The DMCalc 300 further comprises a communication interface 414 (wired or wireless) over which it is configured to transmit and receive data.

[0090] The aspects of the present disclosure have mainly been described above with reference to a few embodiments and examples thereof. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

[0091] Thus, while various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

CLAIMS1. A computer implemented method of a device (300) of assisting a non-terrestrial network (200) to serve at least one wireless communication device (110), comprising:acquiring (S101) information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of the terrestrial network (100);creating (S102), based on the acquired information, beamforming control data specifying how beamforming should be performed by the non-terrestrial network (200) to serve said at least one wireless communication device (110) while complying with a quality criterion; andcontrolling (S103) the beamforming of the non-terrestrial network (200) for serving said at least one wireless communication device (110) based on the created beamforming control data.

2. The method of claim 1, wherein the controlling (S103) the beamforming of the non-terrestrial network (200) for serving said at least one wireless communication device (110) based on the created beamforming control data comprises:providing (S103) the created beamforming control data to the non-terrestrial network (200) with an instruction to apply (S104) the created beamforming control data upon serving said at least one wireless communication device (110).

3. The method of claims 1 or 2, wherein the information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of the terrestrial network (100) is received (S101) from the terrestrial network (100) with a handover request for said at least one wireless communication device (110).

4. The method of claim 3, further comprising:providing (8103a) the terrestrial network (100) with an instruction to perform handover of said at least one wireless communication device (110) to the nonterrestrial network (200).

5. The method of any one of the preceding claims, wherein said information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of theterrestrial network (no) comprises:characteristics of said at least one wireless communication device (no) including one or more of historical and / or future traffic patterns, mobility patterns, demands, policies, handover history.

6. The method of any one of the preceding claims, wherein said information indicating capability of the terrestrial network (too) to serve said at least one wireless communication device (no) in at least one selected coverage area (118) of the terrestrial network (no) comprises one or more of:an indication of one or more wireless communication devices (110-115) that the terrestrial network (100) requests to handover to the non-terrestrial network (200), one or more wireless communication devices (110-115) that the terrestrial network (100) considers as candidates for handover to the non-terrestrial network (200), one or more wireless communication devices (110-115) that the terrestrial network (100) considers as candidates for handover to the non-terrestrial network (200) should the load in the terrestrial network (100) increase to a load threshold, one or more wireless communication devices (110-115) being in vicinity of parts of the coverage area (118) where coverage is below a coverage threshold or in vicinity to an edge of the coverage area (118), one or more wireless communication devices (110-115) that of a certain type, class or category, and / or one or more wireless communication devices (110-115) with a certain type or certain types of subscription.

7. The method of any one of the preceding claims, wherein said information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of the terrestrial network (110) comprises one or more of:status of wireless channels and / or radio access equipment (116, 117) in the coverage area (118), geographical coverage and shape of the coverage area (118), cell related traffic or load information of the coverage area (118).

8. The method of any one of the preceding claims, further comprising:acquiring (Sioia) information indicating capability of the non-terrestrial network (200) to serve said at least one wireless communication device (110) in said at least one selected coverage area (118) of the terrestrial network (100), wherein the creating (S102) of the beamforming control data further takes into account saidacquired information indicating capability of the non-terrestrial network (200) to serve said at least one wireless communication device (110).

9. The method of claim 8, wherein said information indicating capability of the non-terrestrial network (200) to serve said at least one wireless communication device (110) comprises one or more of:weather or atmospheric conditions, terrain type and elevation.

10. The method of claims 8 or 9, wherein said information indicating capability of the non-terrestrial network (200) to serve said at least one wireless communication device (110) comprises one or more of:observations indicating demand in the terrestrial network (100), temporary or permanent occlusions that may obstruct signals of the non-terrestrial network (200)11. The method of any one of the preceding claims, wherein said information indicating capability of the terrestrial network (100) and / or the non-terrestrial network (200) to serve said at least one wireless communication device (110) is provided at multiple time instances.

12. The method of any one of the preceding claims, wherein the created beamforming control data is configured to cause beamforming at the non-terrestrial network (200), the causing of the beamforming including one or more of:steering and / or controlling beam(s) of a satellite (201) in terms of their directions, widths and shapes, on / off status, and number of beams.

13. The method of any one of the preceding claims, wherein the created beamforming control data is configured to include instructions to the non-terrestrial network (200) to prioritize areas with high aggregated demand and / or with limited coverage and steer the satellite beam(s) to cover those areas upon executing the beamforming control data.

14. The method of any one of the preceding claims, wherein the created beamforming control data is configured to cause beamforming for a plurality of satellites in the non-terrestrial network (200).

15. The method of any one of the preceding claims, wherein the creating (S102) of the beamforming control data comprises:training an artificial intelligence, Al, model with the acquired information, and subsequently supplying the trained Al model with further acquired information for having the trained Al model create the beamforming control data.

16. The method of claim 15, further comprising:receiving (S106) a reward from the non-terrestrial network (200) indicating to the Al model a degree of success attained upon applying (S104) the beamforming control data at the non-terrestrial network (200).

17. The method of claims 15 or 16, further comprising:receiving (S107) a reward from the terrestrial network (100) indicating to the Al model a degree of success attained upon applying (S104) the beamforming control data at the non-terrestrial network (200).

18. The method of any one of the preceding claims, wherein the quality criterion to be complied with relates to quality of a service to be provided to said at least one wireless communication device (110).

19. A computer program (412) comprising computer-executable instructions for causing the device (300) to perform steps recited in any one of claims 1-18 when the computer-executable instructions are executed on a processing unit (411) included in the device (300).

20. A computer program product comprising a computer readable medium (413), the computer readable medium having the computer program (412) according to claim 19 embodied thereon.

21. A device (300) configured to assist a non-terrestrial network (200) to serve at least one wireless communication device (110), the device (300) comprising a processing unit (411) and a memory (413), said memory containing instructions (412) executable by said processing unit (411), whereby the device (300) is operative to: acquire (S101) information indicating capability of the terrestrial network (100) to serve said at least one wireless communication device (110) in at least one selected coverage area (118) of the terrestrial network (100);create (S102), based on the acquired information, beamforming control data specifying how beamforming should be performed by the non-terrestrial network(200) to serve said at least one wireless communication device (no) while complying with a quality criterion; andcontrol (S103) the beamforming of the non-terrestrial network (200) for serving said at least one wireless communication device (110) based on the created beamforming control data.

22. The device (300) of claim 21, further being operative to perform the method as claimed in any one of claims 2 to 18.

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