Air user equipment, radio access network node and methods thereof

Abstract

An air user equipment, an air UE, receives, from a network in a first cell, NTZ-related information including geographic information defining a geographic range of a forbidden transmission zone, NTZ, for the air UE. For example, this helps to solve problems related to implementation of a mechanism for allowing an over-the-air UE to comply with NTZ.

Description

Technical Field

[0001] This disclosure relates to radio communication systems, and more particularly to air user equipment (UE). Background Technology

[0002] 3GPP Release 15 and later support over-the-air user equipment (UE) communications. In 3GPP Releases 15-17, the following functionalities support mechanisms based on the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) for providing Long Term Evolution (LTE) connectivity to UEs capable of over-the-air communications:

[0003] - Subscription-based over-the-air UE identification and authorization;

[0004] - Height reporting for events where the UE's height exceeds a reference height threshold configured by the network;

[0005] - Interference detection based on measurement reports, which are triggered when a configured number of cells (i.e., more than one cell) simultaneously meet the triggering criteria;

[0006] - Signaling for flight path information from UE to E-UTRAN;

[0007] - Location information report, including the UE's horizontal and vertical velocity.

[0008] In 3GPP Release 18, there are plans to support similar functionality to the above to provide New Radio (NR) communication to over-the-air UEs (see, for example, Non-Patent Literature 1-6).

[0009] The European Conference on Postal and Telecommunications Administration (CEPT) Electronic Communications Committee (ECC) decision (22)07, dated 8 November 2022, specifies the technical conditions for out-of-band (OOB) transmission restrictions specific to air-to-the-ground (UE) devices and prohibited transmission zones (NTZs) specific to air-to-the-ground (NTZs) (see Non-Patent Document 7). An NTZ is a geographical area in which air-to-the-ground (NTZ) devices are not permitted to operate in a specific frequency band to ensure coexistence with other radio systems and services, such as Digital Terrestrial Television (DTT) receivers, Radio Astronomy Service (RAS) sites, and radar sites. ECC Decision (22)07 requires that the prohibited transmission zones (NTZs) described in the decision be defined and enforced at the national level, and coordinated with neighboring countries as needed.

[0010] The coexistence conditions described in ECC Decision (22)07 are presented below. These coexistence conditions are established under the assumption that a mechanism exists to distinguish between airborne UEs and conventional UEs, and that this mechanism cannot be altered by the end user. A mechanism is required to ensure that airborne UEs comply with the NTZ. In ECC Decision (22)07, the term airborne UE means a UE that supports Unmanned Aircraft System (UAS) features and services and requires an airborne subscription. Airborne UEs can be installed on unmanned aerial vehicles (e.g., drones) or manned aircraft (e.g., helicopters, flying taxis, etc.).

[0011] For example, for airborne UEs operating in the 703-733MHz range, NTZ is required above ground level up to 30m in height to avoid interference with DTT receivers. In other words, airborne UEs operating in the 703-733MHz range should not transmit at heights less than 30m above ground level.

[0012] For example, for airborne UEs operating in the 703-718MHz band, a nationally determined NTZ may be required around RAS sites operating in the 1400-1427MHz band, depending on the circumstances.

[0013] For example, for airborne UEs operating in the 832-837MHz band, a nationally determined NTZ may be required around RAS sites operating in the 1660-1670MHz band, depending on the circumstances.

[0014] For example, for airborne UEs operating in the 2500-2570MHz or 2570-2620MHz bands, a nationally determined NTZ is required around RAS sites operating in the 2690-2700MHz band, depending on the circumstances.

[0015] For example, for airborne UEs operating in the 2500-2570MHz or 2570-2620MHz band, a nationally determined NTZ may be required around radars operating in the 2700-2900MHz band.

[0016] Non-Patent Document 6 contains the following description of a mechanism for satisfying the NTZ requirement specified in ECC Decision (22)07 of the CEPT ECC. If the NTZ is to be interpreted in a very strict manner, this would mean that an airborne UE (e.g., an unmanned aerial vehicle (UAV)) should not make initial access to a cell within the NTZ. In that case, it would be impossible for the airborne UE to even camp on such a cell. In contrast, in a less strict scenario, the airborne UE can access the cell but be redirected to another cell for further transmission. The airborne UE can see several cells and may potentially be served by distant cells even if the airborne UE itself is in or near the NTZ. Another aspect to consider is the potential interference with neighboring cells. In the case where the airborne UE is in the NTZ but connected to another cell, the airborne UE may cause unwanted interference. The same applies if the airborne UE is close to the NTZ.

[0017] For over-the-air UEs, two mechanisms can be envisioned to comply with NTZ. One is a cell-level granular mechanism, and the other is a finer-grained mechanism. At the cell level, radio access network (RAN) nodes take cell-level measures to prohibit over-the-air UEs from accessing cells affected by NTZ.

[0018] With finer granularity, airborne UEs in Radio Resource Control (RRC)_Connected mode notify the RAN node when the UE enters or leaves the NTZ. Signaling can be defined for airborne UEs in RRC_CONNECTED mode to notify the RAN node when the airborne UE enters the NTZ, allowing the network to prepare to maintain connectivity with that airborne UE (e.g., to switch to another permitted frequency band or carrier in the NTZ). Conversely, knowing when an airborne UE is leaving the NTZ makes it possible for the network to revert to its previous communication mode with the airborne UE. This may be necessary, for example, to monitor interference caused by airborne UEs near the NTZ.

[0019] The first (cell-level) mechanism offers several advantages. First, it applies to UEs in both connected and idle modes. Second, it requires less work within the 3GPP Technical Specification Group (TSG) Radio Access Network (RAN) Working Group #2 (WG2). Specifically, only one bit of the system information broadcast by the network is needed to prevent over-the-air UEs from accessing cells affected by NTZ.

[0020] Non-patent document 6 proposes a signaling method that allows NTZ-affected cells to prohibit over-the-air UEs from accessing the network.

[0021] Existing technical documents

[0022] Non-patent literature

[0023] [Non-Patent Document 1] 3GPP TS 23.256 V18.1.0 (2023-06), “Third Generation Partnership Project; Technical Specification Group Services and Systems Aspects; Support for Unmanned Aerial Systems (UAS) Connectivity, Identification and Tracking; Phase 2 (Version 18)”, June 2023

[0024] [Non-Patent Literature 2] InterDigital, “Report from Session on NES, UAV, Rel-15-17UP, Rel-17 Small Data, IIoT / URLLC, and RACH partitioning”, R2-2306543, 3GPPTSG-RAN WG2 Meeting #122, Incheon, South Korea, May 22-26, 2023

[0025] [Non-Patent Document 3] Nokia, Nokia Shanghai Bell, “Stage-2 Text Proposal for Rel-18 UAVs”, R2-2305886, 3GPP TSG-RAN WG2 Meeting #122, Incheon, South Korea, May 22-26, 2023

[0026] [Non-Patent Document 4] Ericsson, “UAV flight path reporting”, R2-2305544, 3GPP TSG-RAN WG2 Meeting #122, Incheon, South Korea, May 22-26, 2023

[0027] [Non-Patent Document 5] Nokia, Nokia Shanghai Bell, “Further Details on Flight Path Plan (FPP)”, R2-2305887, 3GPP TSG-RAN WG2 Meeting #122, Incheon, South Korea, May 22-26, 2023

[0028] [Non-Patent Document 6] Ericsson, “No-transmit zones for UAVs”, RP-231203, 3GPP TSGRAN Meeting #100, Taipei, China, June 12-14, 2023

[0029] [Non-Patent Document 7] European Conference on Postal and Telecommunications Administration (CEPT), “Harmonized technical conditions for the usage of aerial UE for communications based on LTE and 5G NR in the bands 703-733 MHz, 832-862 MHz, 880-915 MHz, 1710-1785 MHz, 1920-1980 MHz, 2500-2570 MHz and 2570-2620 MHz harmonized for MFCN”, ECC / DEC / (22)07, November 18, 2022 Summary of the Invention

[0030] The problem the invention aims to solve

[0031] The inventors examined the mechanisms for addressing the NTZ requirements specified in ECC Decision (22)07 for CEPT ECC and identified various issues. Some of these issues involve the use of NTZ geographic information by airborne UEs. Non-Patent Document 6 describes how airborne UEs in RRC_CONNECTED mode notify the RAN node when entering or leaving the NTZ at a finer granularity than the cell level. However, Non-Patent Document 6 does not disclose further details, and the procedures and signaling details that enable airborne UEs to comply with the NTZ remain unclear.

[0032] One of the objectives of the exemplary embodiments disclosed herein is to provide apparatus, methods, and procedures that help resolve at least one of several problems (including the aforementioned problems) related to implementing mechanisms that enable over-the-air UEs to comply with NTZ. It should be noted that this objective is only one of the objectives of the exemplary embodiments disclosed herein. Other objectives or problems and novel features will become apparent from the following description and accompanying drawings.

[0033] Solution for solving the problem

[0034] In the first aspect, the airborne UE is configured to receive NTZ-related information from the network in the first cell, which includes geographic information for defining the geographic range of the prohibited transmission zone, i.e., the NTZ, for the airborne UE.

[0035] In a second aspect, a method performed by an airborne UE includes receiving, in a first cell, NTZ-related information from a network that contains geographic information for defining the geographic range of an NTZ for the airborne UE.

[0036] In the third aspect, the RAN node is configured to transmit NTZ-related information, which includes geographic information for defining the geographic range of the NTZ for the airborne UE, to the airborne UE in the first cell.

[0037] In a fourth aspect, a method performed by a RAN node includes transmitting NTZ-related information, which contains geographic information for defining the geographic range of the NTZ for the airborne UE, to an airborne UE in a first cell.

[0038] In the fifth aspect, the program includes an instruction set (software code) that, if loaded into a computer, causes the computer to perform the methods according to any of the foregoing aspects.

[0039] Advantages of the invention

[0040] Based on the above aspects, apparatus, methods, and procedures may be provided to help resolve at least one of several problems related to the implementation of mechanisms that enable airborne UEs to comply with NTZ. Attached Figure Description

[0041] Figure 1 This is a diagram illustrating an example configuration of a radio communication system associated with one or more example embodiments.

[0042] Figure 2 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0043] Figure 3 This is a flowchart illustrating an example of the operation of an airborne UE associated with one or more example embodiments.

[0044] Figure 4 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0045] Figure 5 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0046] Figure 6 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0047] Figure 7 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0048] Figure 8This is a diagram illustrating an example of the format of a System Information Block Type 3 (SIB3) information element associated with one or more example embodiments.

[0049] Figure 9 This is a diagram illustrating an example of the format of a SIB Type 4 (SIB4) information element associated with one or more example embodiments.

[0050] Figure 10 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0051] Figure 11 This is a diagram illustrating an example of the format of SIB3 information elements associated with one or more example embodiments.

[0052] Figure 12 This is a diagram illustrating an example of the format of SIB4 information elements associated with one or more example embodiments.

[0053] Figure 13 This is a sequence diagram illustrating examples of signaling between RAN nodes associated with one or more example embodiments.

[0054] Figure 14 This is a flowchart illustrating an example of the operation of a RAN node associated with one or more example embodiments.

[0055] Figure 15 This is a flowchart illustrating an example of the operation of a RAN node associated with one or more example embodiments.

[0056] Figure 16 This is a diagram illustrating an example of the format of the Served Cell Information (NR) information element associated with one or more example embodiments.

[0057] Figure 17 This is a diagram illustrating an example of the format of a proximity information (NR) information element associated with one or more example embodiments.

[0058] Figure 18 This is a diagram illustrating an example configuration of a RAN node associated with one or more example embodiments.

[0059] Figure 19 This is a sequence diagram illustrating examples of signaling between a central unit and distributed units associated with one or more example embodiments.

[0060] Figure 20 This is a sequence diagram illustrating examples of signaling between a central unit and distributed units associated with one or more example embodiments.

[0061] Figure 21 This is a sequence diagram illustrating examples of signaling between a central unit and distributed units associated with one or more example embodiments.

[0062] Figure 22 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0063] Figure 23 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0064] Figure 24 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0065] Figure 25 This is a flowchart illustrating an example of the operation of an airborne UE associated with one or more example embodiments.

[0066] Figure 26 This is a flowchart illustrating an example of the operation of an airborne UE associated with one or more example embodiments.

[0067] Figure 27 This is a sequence diagram illustrating examples of the operation of an airborne UE and RAN node associated with one or more example embodiments.

[0068] Figure 28 This is a block diagram illustrating an example configuration of an airborne UE associated with one or more example embodiments.

[0069] Figure 29 This is a block diagram illustrating an example configuration of a RAN node associated with one or more example embodiments.

[0070] Example Implementation

[0071] In the following, specific exemplary embodiments will be described in detail with reference to the accompanying drawings. Identical or corresponding elements are designated by the same symbols throughout the drawings, and repeated explanations are omitted where necessary for clarity.

[0072] The various example embodiments described below can be implemented independently or in any suitable combination. These various example embodiments have novel features that differ from each other. Therefore, these various example embodiments help to achieve different purposes or solve different problems and help to achieve different advantages.

[0073] The various accompanying drawings or figures are merely examples illustrating one or more exemplary embodiments. Each figure may not be associated with only one specific exemplary embodiment, but may be associated with one or more other exemplary embodiments. As will be understood by those skilled in the art, various features or steps described with respect to any figure may be combined with features or steps illustrated in one or more other figures to produce exemplary embodiments, such as those not explicitly illustrated or described. Not all features or steps illustrated in any figure to describe exemplary embodiments are necessarily necessary, and some features or steps may be omitted. The order of steps described in any figure may be appropriately changed.

[0074] The following example embodiments are described primarily in the context of 3GPP fifth-generation mobile communication systems (5G systems). However, these example embodiments can also be applied to other radio communication systems that support radio terminals similar to 3GPP air-to-air UEs.

[0075] As used in this specification, depending on the context, “if” can be interpreted as “when,” “at or around the time,” “after,” “upon,” “in response to determination,” “according to determination,” or “in response to detection.” Depending on the context, these expressions can be interpreted as referring to the same thing.

[0076] First, the configuration and operation of several network elements common to multiple example embodiments are described. Figure 1 An example configuration of a radio communication system associated with several example embodiments is shown. Figure 1 The various elements shown are network functions, such as providing interfaces defined by 3GPP. Figure 1 The various elements (or network functions) shown can be implemented as, for example, network elements on dedicated hardware, software instances running on dedicated hardware, or virtualization functions instantiated on an application platform.

[0077] Figure 1 The illustrated radio communication system includes an airborne UE 1 and multiple RAN nodes 2 (specifically, RAN nodes 2A to 2G). In the following description, unless otherwise stated, reference will be made to RAN nodes 2 to describe matters common to the multiple RAN nodes 2A-2G. RAN node 2 can be, for example, any one of RAN nodes 2A-2G. Similarly, unless otherwise stated, reference will be made to cell 21 to describe matters common to the multiple cells 21A to 21G. Cell 21 can be, for example, any one of cells 21A to 21G.

[0078] Airborne UE 1 is a UE that supports or is capable of airborne UE communication. Airborne UE 1 can be installed on a UAV (e.g., a drone) or a manned aircraft (e.g., a helicopter, a flying taxi, etc.). Airborne UE 1 can be an LTE airborne UE or an NR airborne UE. Airborne UE 1 can be referred to by other terms such as UAV UE, UAV radio terminal, airborne radio terminal, UAV mobile terminal, airborne mobile terminal, UAV mobile station, airborne mobile station, UAV radio transmit / receive unit (WTRU), or airborne WTRU.

[0079] RAN Node 2 can be referred to as a base station, radio station, or access point. RAN Node 2 can be an E-UTRAN node or an NG-RAN node. RAN Node 2 can be a combination of a Central Unit (CU) (e.g., gNB-CU) and one or more Distributed Units (DUs) (e.g., gNB-DU) in a cloud RAN (C-RAN) deployment. C-RAN is also known as CU / DU splitting. Furthermore, a CU can contain a Control Plane (CP) unit (e.g., gNB-CU-CP) and one or more User Plane (UP) units (e.g., gNB-CU-UP).

[0080] RAN nodes 2A to 2G provide cells 21A to 21G respectively. One RAN node 2 can provide more than one cell. Figure 1 At least two of the illustrated cells 21A to 21G can be provided by a single RAN node 2. Figure 1 The dimensions of cells 21A to 21G shown are for illustrative purposes only. The dimensions of cells 21A to 21G may differ from one another. For example, any cell in cells 21A to 21G may be a macrocell, any cell in the other cells may be a microcell, and any cell in the remaining cells may be a picocell. Any cell in cells 21A to 21G may be contained in or covered by any cell in the other cells. The frequency bands (e.g., NR operating bands or NR radio frequency (RF) carriers) of cells 21A to 21G may differ from one another.

[0081] exist Figure 1 In the example, airborne UE 1 flies through cells 21A, 21B, and 21C in this order. In other words, the flight path of airborne UE 1 sequentially includes waypoints in cells 21A, 21B, and 21C. Each waypoint is defined by a three-dimensional location. The flight path of airborne UE 1 contains multiple waypoints, each defined as a three-dimensional location.

[0082] exist Figure 1In the example shown, a forbidden transmission zone (NTZ) 3 specific to the airborne UE is defined. The geographical scope of NTZ 3 extends over cells 21B, 21C, 21E, and 21G. As previously mentioned, NTZ 3 is a geographical area where airborne UEs are not permitted to operate in a specific frequency band to ensure coexistence with other radio systems and services, such as DTT receivers, RA sites, and radar sites. NTZ 3 can be defined and enforced at the national level. For example, for an airborne UE operating in the 703-718MHz band, NTZ 3 can be defined around RAS sites operating in the 1400-1427MHz band. For an airborne UE operating in the 832-837MHz band, NTZ 3 can be defined around RAS sites operating in the 1660-1670MHz band. For airborne UEs operating in the 2500-2570MHz or 2570-2620MHz band, NTZ 3 can be defined around RAS sites operating in the 2690-2700MHz band. Alternatively, for airborne UEs operating in the 2500-2570MHz or 2570-2620MHz band, NTZ 3 can be defined around radars operating in the 2700-2900MHz band.

[0083] The definition of the geographic shape of NTZ 3 is not limited to Figure 1 The definition shown in the example. In Figure 1 In this context, NTZ 3 can be defined as a three-dimensional region comprising a circular ground area with a predetermined radius centered at a predetermined location (e.g., a RAS site or radar site) and the airspace above that ground area up to a predetermined height. Alternatively, NTZ 3 can be defined as a spherical three-dimensional region with a predetermined radius centered at a predetermined location. NTZ 3 can be defined as a three-dimensional region with an elliptical shape centered at a predetermined location. NTZ 3 can be defined as a three-dimensional region comprising a square ground area centered at a predetermined location and the airspace above that ground area up to a predetermined height. NTZ 3 can be defined as a three-dimensional region with a cubic or cuboid shape centered at a predetermined location.

[0084] If NTZ 3 is to be interpreted very strictly, this would mean that over-the-air UE 1 should not target cells in NTZ 3 or cells that partially overlap with NTZ 3 (e.g., Figure 1 Initial access is performed in cells 21B, 21C, 21E, and 21G. In this case, it is even impossible for the airborne UE 1 to camp on these cells that at least partially overlap with NTZ 3. In contrast, in a less strict scenario, the airborne UE 1 can access these cells that at least partially overlap with NTZ 3, but the airborne UE 1 is redirected to another cell for further transmission.

[0085] For over-the-air UE 1, two mechanisms can be envisioned to comply with NTZ 3. One is a cell-level granular mechanism, and the other is a finer-grained mechanism. For example, at the cell level, one or more RAN nodes 2 can take cell-level measures to prevent over-the-air UE 1 from accessing cells affected by NTZ, such as... Figure 1 The communities in question are 21B, 21C, 21E, and 21G.

[0086] At a finer granularity, an airborne UE 1 in RRC_CONNECTED mode can notify RAN node 2 when the UE is entering or leaving NTZ 3. Airborne UE 1 can use Global Navigation Satellite System (GNSS) positioning information to obtain its location. Signaling can be defined for airborne UE 1 in RRC_CONNECTED mode to notify RAN node 2 whether airborne UE 1 is approaching or entering NTZ 3. This allows the network (e.g., one or more RAN nodes 2) to prepare to maintain connectivity with airborne UE 1 (e.g., to switch to another frequency band or carrier permitted in NTZ 3). Conversely, knowing when airborne UE 1 is leaving NTZ 3 at a certain timing makes it possible for the network (e.g., one or more RAN nodes 2) to revert to its previous communication mode with airborne UE 1.

[0087] The example embodiments described below provide operations, procedures, and signaling for air 1 and RAN node 2 that help or assist in implementing mechanisms that enable air UEs to comply with NTZ.

[0088] First Example Implementation

[0089] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 2 An example of signaling between UE 1 and RAN node 2 is illustrated. In step 201, RAN node 2 (e.g., Figure 1 RAN node 2B in cell 21 (e.g., Figure 1 System information is transmitted via broadcast in cell 21B. The system information can be a Master Information Block (MIB) or any System Information Block (SIB) (e.g., SIB type 1 (SIB1) or SIB type 2 (SIB2)).

[0090] The system information in step 201 includes information indicating whether the cell is blocked for the over-the-air UE. This information can be a single bit. This information can be an enumerated type information element (IE) and can indicate "blocked" or "not blocked". For example, the IE could be named "cellBarredUAV", but is not limited to this name. This information or IE can be applied to all public land mobile networks (PLMNs) and non-public networks (NPNs) associated with the cell. This information or IE can be included in the MIB or SIB1, similar to other information elements indicating cell status and cell reservation (e.g., cellBarred IE, cellBarredNTN IE, cellBarredRedCap1Rx, cellReservedForOtherUse).

[0091] If cell 21 is included in or partially overlaps with NTZ 3 for airborne UEs, and if the uplink frequency of cell 21 falls within a prohibited band in NTZ 3, then RAN Node 2 may indicate to airborne UE 1 via information or IE (e.g., cellBarredUAV) that cell 21 is prohibited for airborne UEs. Otherwise, RAN Node 2 may indicate to airborne UE 1 via information or IE that cell 21 is not prohibited for airborne UEs. Alternatively, RAN Node 2 may indicate that cell 21 is not prohibited for airborne UEs by omitting information or IE from the system information.

[0092] Figure 3 An example of the operation of air UE 1 is illustrated. In step 301, air UE 1 receives system information (e.g., SIB1) via broadcast in cell 21. In step 302, air UE 1 determines whether the received system information contains an IE (e.g., cellBarredUAV) indicating whether cell 21 is blocked for the air UE.

[0093] If the system information contains an IE ("Yes" in step 302) and the IE indicates that the cell is banned for the air UE ("Yes" in step 303), then the air UE 1 will consider the cell as a banned cell in cell selection or cell reselection (step 304). In other words, the air UE 1 excludes cell 21 from the candidate cells used for cell selection or cell reselection. Conversely, if the system information contains the IE in question ("Yes" in step 302) and the IE indicates that the cell is not banned for the air UE ("No" in step 303), then the air UE 1 will not consider the cell as a banned cell in cell selection or cell reselection (step 305). Additionally, if the system information does not include the IE ("No" in step 302), then the air UE 1 will not consider cell 21 as a banned cell in cell selection or cell reselection (step 305).

[0094] According to the reference Figure 2 and Figure 3 The described operation states that if information indicating whether cell 21 is prohibited for the airborne UE or an IE (e.g., cellBarredUAV) is not broadcast in cell 21, then airborne UE 1 can assume that access to cell 21 is not prohibited. This helps to clarify the signaling and UE behavior details related to the mechanisms that enable airborne UEs to comply with NTZ.

[0095] Second Example Implementation

[0096] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 4 , Figure 5 and Figure 6 An example of signaling between over-the-air UE 1 and RAN node 2 is illustrated. In steps 401, 501, and 601, RAN node 2 (e.g., Figure 1 RAN node 2B in cell 21 (e.g., Figure 1 NTZ-related information is transmitted via broadcast in cell 21B. NTZ-related information may be included in system information (e.g., MIB, SIB1, or other SIBs).

[0097] exist Figure 4In the example, the NTZ-related information (step 401) indicates that cell 21 belongs to or contains NTZ3 for the airborne UE. In other words, the NTZ-related information (step 401) indicates that at least a portion of cell 21 overlaps with NTZ 3. If airborne UE 1 receives the NTZ-related information (step 401) in cell 21, airborne UE 1 can understand that uplink transmissions are not permitted for the airborne UE in the cell. More specifically, airborne UE 1 can understand that in cell 21, initial access from RRC_IDLE, RRC reconstruction, RRC restart from RRC_INACTIVE, and random access associated with all uplink transmissions from the airborne UE are restricted.

[0098] exist Figure 5 In the example, the NTZ-related information (step 501) indicates that uplink transmission is not permitted for the airborne UE in cell 21. If airborne UE 1 receives the NTZ-related information (step 501) in cell 21, airborne UE 1 can understand that uplink transmission is not permitted for the airborne UE in the cell. More specifically, airborne UE 1 can understand that in cell 21, initial access from RRC_IDLE, RRC reconstruction, RRC restart from RRC_INACTIVE, and random access associated with all uplink transmissions from the airborne UE are restricted.

[0099] exist Figure 6 In the example, the NTZ-related information (step 601) instructs cell 21 to provide downlink communication services to the air UE, but not uplink communication services. Such a cell can be called a supplementary downlink cell. If air UE 1 receives the NTZ-related information (step 601) in cell 21, air UE 1 can understand that downlink data reception is allowed in cell 21, but uplink data transmission is not allowed.

[0100] The air-to-air UE 1 may consider NTZ-related information for either or both of cell selection and cell reselection (steps 401, 501, or 601). For example, during cell selection or reselection, the air-to-air UE 1 may select a cell that is not transmitting NTZ-related information over a cell that is currently transmitting such information. For example, if SIB2 includes a rangeToBestCell field, the air-to-air UE 1 may reselect a cell from multiple candidate cells whose R values—calculated using average reference received signal power (RSRP)—fall within the range specified by the rangeToBestCell field relative to the highest-ranked cell, towards a cell that is not transmitting NTZ-related information. Alternatively, the air-to-air UE 1 may treat cells transmitting NTZ-related information (steps 401, 501, or 601) as prohibited cells during cell selection or cell reselection.

[0101] NTZ-related information can be an enumerated type IE and can indicate "true". This IE can be named, for example, "noTransmitZoneUAV", "noRachULtransmitUAV", or "supplementaryDLUA", but is not limited to these names. This information or IE can be applied to all PLMNs and NPNs associated with the cell. The information or IE can be included in the MIB or SIB1, similar to other information elements indicating cell status and cell reservations (e.g., cellBarred IE, cellBarredNTN IE, cellBarredRedCap1Rx, cellReservedForOtherUse).

[0102] If cell 21 is included in or partially overlaps with NTZ 3 for airborne UEs, and the uplink frequency of cell 21 falls within a prohibited band in NTZ 3, then RAN node 2 may broadcast the aforementioned NTZ-related information in cell 21. Otherwise, RAN node 2 may indicate that cell 21 is not prohibited for airborne UEs by not transmitting the aforementioned NTZ-related information in cell 21.

[0103] According to the reference Figure 4 , Figure 5 and Figure 6 The described operation allows RAN node 2 to broadcast to the air UE whether cell 21 is within the NTZ for the air UE, whether uplink transmissions by the air UE in cell 21 are prohibited, or whether cell 21 is dedicated to downlink services for the air UE. This helps to clarify the signaling details related to the mechanisms that enable the air UE to comply with the NTZ.

[0104] Third Example Implementation

[0105] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 7 An example of signaling between over-the-air UE 1 and RAN node 2 is illustrated. In step 701, RAN node 2 (e.g., Figure 1 RAN node 2A in its own cell 21 (e.g., Figure 1 In cell 21A, a list of excluded cells specific to the over-the-air UE is transmitted. RAN node 2 (e.g., Figure 1 RAN node 2A in the RAN can include one or more neighboring cells in the exclusion cell list specific to the airborne UE (e.g., Figure 1 Cell 21B in the NTZ 3, wherein one or more neighboring cells at least partially overlap with NTZ 3 and the uplink frequency of one or more neighboring cells falls within a prohibited frequency band in NTZ 3.

[0106] RAN Node 2 can transmit an air UE-specific excluded cell list to air UE 1 via a Dedicated Radio Resource Control (RRC) message or via common system information in cell 21. RAN Node 2 can transmit or broadcast the air UE-specific excluded cell list via SIB Type 3 (SIB3) or SIB Type 4 (SIB4).

[0107] Air-based UE 1 can exclude one or more cells included in the received excluded cell list from candidate cells used for cell reselection. Additionally or alternatively, air-based UE 1 can exclude cells included in the excluded cell list from primary cell candidates used for carrier aggregation. Additionally or alternatively, air-based UE 1 can exclude one or more cells included in the received excluded cell list, preventing those cells from undergoing Radio Resource Management (RRM) measurements for cell reselection. Additionally or alternatively, air-based UE 1 can exclude one or more cells included in the received excluded cell list, preventing those cells from undergoing IDLE / INACTIVE measurements. IDLE / INACTIVE measurements were introduced in 3GPP Release 16. IDLE / INACTIVE measurements are a feature in which UE 1 acquires and stores measurement results of the stored cell and neighboring cells when in RRC_IDLE or RRC_INACTIVE state, and transmits the stored measurement results to the network when in RRC_CONNECTED state.

[0108] According to the reference Figure 7The described operation allows RAN node 2 to transmit a list of excluded cells specific to the air UE in its own cell 21. This helps to clarify the details of the signaling related to the mechanisms that enable air UEs to comply with NTZ (particularly the signaling related to cell reselection by the air UE).

[0109] Figure 8 An example of the format of a SIB3 Information Element (IE) is shown. A SIB3 IE contains neighboring cell information relevant only to intra-frequency cell reselection. A SIB3 IE includes cells with specific reselection parameters and cells from an exclusion list. Figure 8 In the example, the SIB3 IE may include the intraFreqExcludedCellListUAV field 801. The intraFreqExcludedCellListUAV field 801 is IntraFreqExcludedCellListUAV IE 802. IntraFreqExcludedCellListUAV IE 802 is an example of the excluded cell list in step 701, i.e., an example of an excluded cell list specific to the air UE. IntraFreqExcludedCellListUAV IE 802 indicates one or more neighboring cells to be excluded during intra-frequency cell reselection by the air UE. The names of field 801 and IE 802 are examples and may differ.

[0110] Figure 9 An example of the SIB4 IE format is shown. The SIB4 IE contains information related to inter-frequency cell reselection (i.e., information about other NR frequencies and neighboring cells between frequencies related to cell reselection). The SIB4 IE can also be used for IDLE / INACTIVE measurements. The SIB4 IE includes common cell reselection parameters and cell-specific reselection parameters for a given frequency. Figure 9In the example, the SIB4 IE may include the interFreqExcludedCellListUAV field 901. The interFreqExcludedCellListUAV field 901 is InterFreqExcludedCellListUAV IE 902. InterFreqExcludedCellListUAV IE 902 is an example of the excluded cell list in step 701, i.e., an example of an excluded cell list specific to the air UE. InterFreqExcludedCellListUAV IE 902 indicates one or more neighboring cells to be excluded during inter-frequency cell reselection by the air UE. Additionally, InterFreqExcludedCellListUAV IE 902 indicates one or more neighboring cells to be excluded from the IDLE / INACTIVE measurements by the air UE. The names of field 901 and IE 902 are examples and may differ.

[0111] Fourth Example Implementation

[0112] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 10 An example of signaling between UE 1 and RAN node 2 over the air is illustrated. In step 1001, RAN node 2 (e.g., Figure 1 RAN node 2A in its own cell 21 (e.g., Figure 1 In cell 21A), a list of neighboring cells specific to the air UE is transmitted. Each cell included in one or more cells in the neighboring cell list is a cell belonging to or containing NTZ 3 for the air UE; a cell where uplink transmission is not permitted for the air UE; or a cell that provides downlink communication services to the air UE but not uplink communication services. RAN Node 2 (e.g., Figure 1 RAN node 2A in the list of neighboring cells can include one or more neighboring cells (e.g., Figure 1 Cell 21B in the NTZ 3, wherein one or more neighboring cells at least partially overlap with NTZ 3 and the uplink frequency of one or more neighboring cells falls within a prohibited frequency band in NTZ 3.

[0113] RAN Node 2 can transmit a UE-specific list of neighboring cells to UE 1 via Dedicated Radio Resource Control (RRC) messages or via common system information in cell 21. RAN Node 2 can also transmit or broadcast the UE-specific list of neighboring cells via SIB3 or SIB4.

[0114] Air UE 1 can exclude one or more cells included in the received neighbor cell list from candidate cells used for cell reselection. Additionally or alternatively, air UE 1 can exclude cells included in the neighbor cell list from primary cell candidates used for carrier aggregation. Additionally or alternatively, air UE 1 can exclude one or more cells included in the received neighbor cell list so that the one or more cells are not subject to RRM measurements used for cell reselection. Additionally or alternatively, air UE 1 can exclude one or more cells included in the received neighbor cell list so that the one or more cells are not subject to IDLE / INACTIVE measurements.

[0115] According to the reference Figure 10 The described operation allows RAN Node 2 to transmit a list of neighboring cells specific to the air UE in its own cell 21. This enables RAN Node 2 to inform air UEs belonging to cell 21 of RAN Node 2 about neighboring cells that belong to or contain NTZ 3 for the air UE, neighboring cells that do not allow uplink transmissions for the air UE, or neighboring cells that provide downlink communication services to the air UE but not uplink communication services. This helps to clarify the signaling details of the mechanisms that enable air UEs to comply with NTZ, particularly the signaling related to cell reselection by the air UE.

[0116] Figure 11 An example of the SIB3 IE format is shown. The SIB3 IE contains neighboring cell information relevant only to intra-frequency cell reselection. The SIB3 IE includes cells with specific reselection parameters and cells from an exclusion list. Figure 11 In the example, the SIB3 IE may include the intraFreqnoRachULtransmitUAV field 1101. The intraFreqnoRachULtransmitUAV field 1101 is IntraFreqnoRachULtransmitUAV IE 1102. IntraFreqnoRachULtransmitUAV IE 1102 is an example of the neighboring cell list in step 1001, i.e., an example of a neighboring cell list specific to the airborne UE. IntraFreqnoRachULtransmitUAV IE 1102 indicates one or more neighboring cells within a frequency range where random access transmissions by the airborne UE are prohibited. The names of field 1101 and IE 1102 are examples and may differ. For example, these names could be IntraFreqnoTransmitZoneUAV or IntraFreqsupplementaryDLUAV.

[0117] Figure 12 An example of the SIB4 IE format is shown. The SIB4 IE contains information related to inter-frequency cell reselection (i.e., information about other NR frequencies and neighboring cells between frequencies related to cell reselection). The SIB4 IE can also be used for IDLE / INACTIVE measurements. The SIB4 IE includes common cell reselection parameters and cell-specific reselection parameters for a given frequency. Figure 12 In the example, the SIB4 IE may include the interFreqnoRachULtransmitUAV field 1201. The interFreqnoRachULtransmitUAV field 1201 is InterFreqnoRachULtransmitUAV IE 1202. InterFreqnoRachULtransmitUAV IE 1202 is an example of the neighboring cell list in step 1001, i.e., an example of a neighboring cell list specific to the air UE. InterFreqnoRachULtransmitUAV IE 1202 indicates one or more frequency-nearer cells where random access transmissions by the air UE are prohibited. The names of field 1201 and IE 1202 are examples and may differ. For example, these names could be InterFreqnoTransmitZoneUAV or InterFreqsupplementaryDLUAV.

[0118] Fifth Example Implementation

[0119] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 13 An example of signaling between two RAN nodes 2 is illustrated. In step 1301, RAN node 2A sends information to its neighboring RAN node 2B indicating whether cell 21A, provided by RAN node 2A, at least partially overlaps with NTZ 3. If cell 21A at least partially overlaps with NTZ 3 and the uplink frequency of cell 21A falls within a prohibited frequency band in NTZ 3, then RAN node 2A can inform RAN node 2B that cell 21A at least partially overlaps with NTZ 3. Otherwise, RAN node 2A can inform RAN node 2B that cell 21A does not overlap with NTZ 3, or even partially overlaps with NTZ 3.

[0120] In step 1302, RAN node 2A receives information from neighboring RAN node 2B indicating whether cell 21B, provided by neighboring RAN node 2B, at least partially overlaps with NTZ 3. If cell 21B at least partially overlaps with NTZ 3 and the uplink frequency of cell 21B falls within a prohibited frequency band in NTZ 3, then RAN node 2B can inform RAN node 2A that cell 21B at least partially overlaps with NTZ 3. Otherwise, RAN node 2B can inform RAN node 2A that cell 21B does not overlap with NTZ 3, or even only partially overlaps with NTZ 3.

[0121] The order of steps 1301 and 1302 is not restricted. The control messages carrying information in each step of steps 1301 and 1302 can be Xn Application Protocol (XnAP) messages, and more specifically, can be, for example, XN SETUP REQUEST, XN SETUP RESPONSE, NG-RAN NODE CONFIGURATION UPDATE, or ACCESS AND MOBILITY INDICATION messages.

[0122] Additionally, RAN node 2A can send to RAN node 2B an indication of the neighboring cells of cell 21A of RAN node 2A—specifically, by one or more neighboring RAN nodes other than RAN node 2B (e.g., Figure 1 RAN nodes 2D and 2F in the RAN provide one or more neighboring cells 21 (e.g., Figure 1 The RAN node 2A can receive information from RAN nodes 2D and 2F regarding whether cells 21D and 21F overlap at least partially with NTZ 3. RAN node 2A can use the same message used in step 1301 to send information about the overlap between neighboring cells 21A and the NTZ to RAN node 2B. Alternatively, RAN node 2A can send this information to RAN node 2B in a separate message.

[0123] Similarly, RAN node 2B can send to RAN node 2A an indication of the various neighboring cells of cell 21B of RAN node 2B—specifically, one or more cells 21 provided by one or more neighboring RAN nodes other than RAN node 2A (e.g., Figure 1The RAN node 2B can receive information from RAN nodes 2C, 2E, and 2G regarding whether cells 21C, 21E, and 21G overlap at least partially with NTZ 3. RAN node 2B can use the same message used in step 1302 to send information about the overlap between neighboring cells and NTZ to RAN node 2A. Alternatively, RAN node 2B can send this information to RAN node 2A in a separate message.

[0124] According to the reference Figure 13 The described operation allows RAN node 2A to exchange or share information about the overlap between cell 21 and NTZ 3 with neighboring RAN node 2B. This helps to clarify the signaling details related to the mechanism that enables over-the-air UEs to comply with NTZ.

[0125] RAN node 2A can use the information received from RAN node 2B regarding the overlap between neighboring cell 21B and NTZ 3 for various purposes or applications. For example, Figure 14 As shown, RAN node 2A can consider or use this information to determine the target cell for handover to airborne UE 1 in the RRC_CONNECTED state. The handover can be a conditional handover (CHO). Additionally or alternatively, such as... Figure 15 As shown, RAN node 2A may consider or use this information to generate an exclusion cell list or a neighboring cell list specific to the air UE, which may be similar to those lists described in the third or fourth example embodiments.

[0126] Figure 14 An example of the operation of RAN node 2A is illustrated. In step 1401, RAN node 2A determines the handover of air UE 1 in the RRC_CONNECTED state. This handover may be a conditional handover (CHO). RAN node 2A may determine the handover of air UE 1 based at least on the receipt of measurement reports from air UE 1. RAN node 2A may determine the handover of air UE 1 based at least on flight path information about air UE 1 received from air UE 1.

[0127] In step 1402, RAN node 2A attempts to select a target cell that does not overlap with NTZ 3 (or even partially overlaps with NTZ 3). If a target cell that does not overlap with NTZ 3 (or even partially overlaps with NTZ 3) is selected, RAN node 2A prepares for handover or CHO to the target cell. Then, RAN node 2A transmits configuration information for handover or CHO to air UE 1. In response to receiving the configuration information for handover, air UE 1 leaves cell 21A and begins accessing the target cell. Alternatively, after receiving the configuration information for CHO and in response to the CHO execution conditions being met, air UE 1 leaves cell 21A and begins accessing the target cell.

[0128] Conversely, if RAN node 2A fails to select a target cell that does not overlap with NTZ 3, or even partially overlap with NTZ 3, then at step 1403, RAN node 2A sends a message to air UE 1 to release the RRC connection of air UE 1. This message may be an RRCRelease message. RAN node 2A includes a reason value in the message indicating that the reason for the RRC connection release is entry into the NTZ. In other words, the message indicates that the reason for the RRC connection release is entry into the NTZ.

[0129] According to the reference Figure 14 The described operation allows RAN node 2A to consider or use information about the overlap between neighboring cells and the NTZ to determine the target cell for handover of air UE 1. This helps to clarify the operational and signaling details related to the mechanisms that enable air UEs to comply with the NTZ, particularly the operational and signaling details related to the handover of air UEs.

[0130] Figure 15 An example of the operation of RAN node 2A is illustrated. In step 1501, RAN node 2A generates an airborne UE-specific neighboring cell list (or neighboring cell list) based on information received from neighboring RAN node 2B regarding overlap with NTZ 3. In step 1502, RAN node 2A broadcasts the generated neighboring cell list (or neighboring cell list) in its own cell 21A.

[0131] The air-to-air UE-specific exclusion cell list may be the same as the exclusion cell list described in the third embodiment. Specifically, the air-to-air UE-specific exclusion cell list may indicate one or more neighboring cells to be excluded from the candidate cells used for cell reselection by the air-to-air UE. RAN node 2A may include cells in the exclusion cell list that at least partially overlap with NTZ 3 and whose uplink frequency falls within the prohibited frequency band in NTZ 3.

[0132] On the other hand, the air UE-specific neighboring cell list can be the same as the neighboring cell list described in the fourth embodiment. Specifically, each cell in the air UE-specific neighboring cell list can be a cell belonging to or containing NTZ 3, a cell that does not allow uplink transmission for the air UE, or a cell that provides downlink communication service to the air UE but not uplink communication service. The air UE-specific neighboring cell list allows the air UE to exclude one or more cells included in the neighboring cell list from the candidate cells used for cell reselection. Additionally or alternatively, the air UE-specific neighboring cell list allows the air UE to exclude cells included in the neighboring cell list from the primary cell candidates used for carrier aggregation. RAN Node 2A can include cells in the neighboring cell list that at least partially overlap with NTZ 3, and whose uplink frequency falls within the prohibited frequency band in NTZ 3.

[0133] According to the reference Figure 15 The described operation allows RAN node 2A to consider or use information related to the overlap between neighboring cells and the NTZ to control cell reselection performed by air UE 1. This helps to clarify the operational and signaling details related to the mechanisms that enable air UEs to comply with the NTZ, particularly the operational and signaling details related to cell reselection by air UEs.

[0134] Figure 16 An example of the format of the Served Cell Information (NR IE) is shown. The Served Cell Information (NR IE) contains cell configuration information for NR cells that neighboring NG-RAN nodes may need for the XnAP interface. For example, the Served Cell Information (NR IE) can be included in the XN SETUP REQUEST, XN SETUP RESPONSE, NG-RAN NODE CONFIGURATION UPDATE, and NG-RAN NODE CONFIGURATION UPDATE ACKNOWLEDGE messages. Figure 16 In the example, the Serving Cell Information NR IE may include UAVNotransmitZone IE 1601. UAVNotransmitZone IE 1601 indicates whether the NR cell associated with the Serving Cell Information NR IE at least partially overlaps with the NTZ of the airborne UE. UAVNotransmitZone IE 1601 may be an enumeration type and may indicate "false" or "true".

[0135] Figure 17An example of the format of the Neighborhood Information (NR IE) is shown. The Neighborhood Information (NR IE) contains cell configuration information of the NR cells that neighboring RAN nodes may need to properly operate their own served cells. For example, the Neighborhood Information (NR IE) can be included in the XN SETUP REQUEST, XN SETUP RESPONSE, NG-RAN NODE CONFIGURATION UPDATE, and NG-RAN NODE CONFIGURATION UPDATE ACKNOWLEDGE messages. Figure 17 In the example, the Neighborhood Information NR IE can include UAVNotransmitZone IE 1701 for each of the neighboring NR cells in one or more neighboring NR cells. UAVNotransmitZone IE 1701 indicates whether the associated neighboring NR cell at least partially overlaps with the NTZ of the airborne UE. UAVNotransmitZone IE 1701 can be an enumeration type and can indicate "false" or "true".

[0136] Sixth Example Implementation

[0137] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. RAN Node 2 can have... Figure 18 The configuration shown. Figure 18 The various elements (or network functions) shown can be implemented as, for example, network elements on dedicated hardware, software instances running on dedicated hardware, or virtualization functions instantiated on an application platform. Figure 18 As shown, RAN node 2 may include CU 22 and one or more DU 23 (e.g., DU23A to 23C). In the following description, unless otherwise stated, the common aspects of the plurality of DU 23A to 23C will be described with reference to DU 23. CU 22 and each DU 23 are connected via interface 24. Air UE 1 is connected to at least one DU 23 via at least one air interface 25.

[0138] CU 22 can be a logical node for the Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols (or the RRC and PDCP protocols of the gNB) of the hosted gNB. DU 23 can be a logical node for the Radio Link Control (RLC), Media Access Control (MAC), and Physical (PHY) layers of the hosted gNB. If CU 22 is a gNB-CU and DU 23 is a gNB-DU, then interface 24 can be an F1 interface. CU 22 can include CU-CP and CU-UP.

[0139] Figure 19 An example of signaling between CU 22 and DU 23 is illustrated. In step 1901, CU 22 sends a first message to DU 23 indicating whether cell 21 provided by or associated with DU 23 at least partially overlaps with NTZ 3 for the over-the-air UE. CU 22 may send the first message to DU 23 via an F1 SETUP RESPONSE, GNB-DU CONFIGURATION UPDATEACKNOWLEDGE, or GNB-CU CONFIGURATION UPDATE message. CU 22 may include the first message in a list of cells to be activated (IE) that can be included in these F1 Application Protocol (F1AP) messages. The list of cells to be activated (IE) contains a list of cells that CU 22 requests DU 23 to activate.

[0140] DU 23 can use the received first information for various purposes or applications. For example, DU 23 can consider or use the first information to decide whether to redirect airborne UE 1 in its own cell 21, which is in the RRC_CONNECTED state, to another cell. DU 23 can use L1 / L2 triggered mobility (LTM) to change the serving cell of airborne UE 1. LTM is the process by which the gNB receives L1 measurement reports from the UE and changes one or more serving cells of the UE based on them via L2 signaling (specifically, MAC control element (CE)).

[0141] According to the reference Figure 19 The described operation allows CU 22 to notify DU 23 whether cell 21 provided by or associated with DU 23 at least partially overlaps with NTZ 3 for an airborne UE. This helps to clarify signaling details related to the mechanisms that enable airborne UEs to comply with NTZ, particularly those related to airborne UE mobility procedures (e.g., LTM).

[0142] Additionally, CU 22 may send a second message to DU 23 (e.g., DU 23A) indicating whether one or more neighboring cells provided by one or more other DU 23s (e.g., DU 23B and DU 23C) at least partially overlap with NTZ 3. Figure 20An example of signaling between CU 22 and DU 23 is illustrated. In step 2001, CU 22 sends a second message to DU 23 (e.g., DU 23A) indicating whether one or more neighboring cells at least partially overlap with NTZ 3 for the airborne UE. CU 22 may send the second message to DU 23 via F1 SETUP RESPONSE, GNB-DU CONFIGURATION UPDATEACKNOWLEDGE, or GNB-CU CONFIGURATION UPDATE messages. CU 22 may include the second message in a list of neighboring cell information (IE) that can be included in these F1 Application Protocol (F1AP) messages.

[0143] DU 23 can use the received second information for various purposes or applications. For example, DU 23 can consider or use the second information to determine another cell to redirect DU 23's own cell 21, where the over-the-air UE 1 is in the RRC_CONNECTED state. DU 23 can consider or use the second information to determine the target cell for LTM.

[0144] According to the reference Figure 20 The described operation allows CU 22 to notify DU 23 whether one or more neighboring cells at least partially overlap with NTZ 3 for an airborne UE. This helps to clarify the signaling details related to the mechanisms that enable airborne UEs to comply with NTZ, particularly those related to airborne UE mobility procedures (e.g., LTM).

[0145] Figure 19 The process described herein can be used in situations or scenarios where CU 22 configures or determines information related to whether a cell at least partially overlaps with NTZ 3. Conversely, situations or scenarios where DU 23 configures or determines information related to whether a cell at least partially overlaps with NTZ 3 are also conceivable. In such cases, CU 22 and DU 23 can perform... Figure 21 The process is shown.

[0146] Figure 21 An example of signaling between CU 22 and DU 23 is illustrated. In step 2101, DU 23 sends a first message to CU 22 indicating whether cell 21 provided by or associated with DU 23 at least partially overlaps with NTZ 3 for the over-the-air UE. DU 23 may send the first message to CU 22 via an F1 SETUP REQUEST or GNB-DU CONFIGURATION UPDATE message. DU 23 may include the first message in the Served Cell Information (IE), which can be included in these F1 Application Protocol (F1AP) messages.

[0147] CU 22 can use the received first information for various purposes or applications. For example, CU 22 can consider or use the received first information to determine a target cell for intra-CU inter-DU handover or CHO. In intra-CU inter-DU handover or CHO, CU 22 can attempt to select a target cell that does not overlap with NTZ 3 (or even partially overlap with NTZ 3). Additionally or alternatively, CU 22 can consider or use the received first information to determine the content of system information (e.g., the system information described in the first or second example embodiments) broadcast in one or more cells 21 provided by one or more DUs 23. Additionally or alternatively, CU 22 can consider or use the received first information to determine the content of an air UE-specific excluded cell list or neighboring cell list (e.g., the excluded cell list or neighboring cell list described in the third or fourth example embodiments). Additionally or alternatively, CU 22 can consider or use the first information received from DU 23 to send the aforementioned second information ( Figure 20 ).

[0148] According to the reference Figure 21 The described operation allows DU 23 to notify CU 22 whether cell 21 provided by or associated with DU 23 at least partially overlaps with NTZ 3 for an airborne UE. This helps to clarify signaling details related to the mechanisms that enable airborne UEs to comply with NTZ, particularly those related to airborne UE mobility procedures (e.g., cell reselection, handover, CHO).

[0149] Seventh Example Implementation

[0150] The example configuration of the radio communication system according to this example embodiment is similar to that in the reference. Figure 1 Example configuration described. Figure 22 An example of signaling between air UE 1 and RAN node 2 is illustrated. In step 201, RAN node 2 transmits NTZ-related information to air UE 1, containing geographic information defining the geographic range of NTZ 3 for the air UE. The NTZ-related information may also contain information indicating one or more frequency bands (e.g., NR operating bands or NR RF carriers) that the air UE is not allowed to transmit in NTZ 3 (e.g., NR band number or NR absolute radio frequency channel number (ARFCN)). RAN node 2 may broadcast the NTZ-related information via cell common or area common system information (e.g., SIB), or may transmit the NTZ-related information to air UE 1 via a dedicated RRC message.

[0151] Figure 22RAN node 2 in (e.g., Figure 1 RAN node 2A in the middle) can be in cell 21 (e.g., not overlapping with NTZ 3 (or even partially overlapping with NTZ 3) Figure 1 In cell 21A, NTZ-related information is transmitted to UE1 over the air. Additionally or alternatively, RAN node 2 (e.g., Figure 1 RAN node 2B in the RAN can at least partially overlap with cell 21 of NTZ 3 (e.g., Figure 1 In cell 21B, NTZ-related information is transmitted from the cell to the airborne UE1.

[0152] As described above, several examples of the geographic shape of NTZ 3 exist. Specifically, for example, NTZ 3 can be defined as a three-dimensional region comprising a circular ground area with a predetermined radius centered at a predetermined location (e.g., a RAS site or radar site) and an airspace above that ground area up to a predetermined height. Alternatively, NTZ 3 can be defined as a spherical three-dimensional region with a predetermined radius centered at a predetermined location. NTZ 3 can be defined as a three-dimensional region with an elliptical shape centered at a predetermined location. NTZ 3 can be defined as a three-dimensional region comprising a square ground area centered at a predetermined location and an airspace above that ground area up to a predetermined height. NTZ 3 can be defined as a three-dimensional region with a cubic or cuboid shape centered at a predetermined location.

[0153] The geographic information used to define the geographic extent of NTZ 3 includes information required to specify these geographic shapes. For example, the geographic information may include information about latitude and longitude to define the location and extent of the geographic extent of NTZ 3. The geographic information may specify the latitude and longitude of the starting and ending points for defining the ground cover of NTZ 3, and the starting and ending altitudes for defining the altitude range of NTZ 3. The geographic information may define the two-dimensional shape of NTZ 3 (e.g., circle, ellipse, quadrilateral), the latitude and longitude of the center point of the two-dimensional shape, and the starting and ending altitudes for defining the altitude range of NTZ 3. The geographic information may also define the three-dimensional shape of NTZ 3 (e.g., sphere, ellipsoid, cube, cuboid) and the latitude and longitude of the center point of the three-dimensional shape.

[0154] According to the reference Figure 22 The described operation allows RAN node 2 to inform air UE 1 of a specific geographic range of NTZ 3. This helps clarify the signaling details related to the mechanisms that enable air UEs to comply with NTZ. Air UE 1 can use or consider the specific geographic range of NTZ 3 for various purposes or applications. Examples of these purposes or applications are as follows.

[0155] Airborne UE 1 can use or consider the geographic information of NTZ 3 to transmit a report to RAN node 2 of the serving cell regarding airborne UE 1's approach to or entry into NTZ 3. Airborne UE 1 can utilize GNSS positioning information to obtain its location. Figure 23 An example of the operation of UE 1 and RAN node 2 in the air is shown. Figure 23 Assume that the air UE 1 is in the RRC_CONNECTED state. In step 2301, the air UE 1 can receive geographical information from the serving RAN node 2 to define the geographical range of NTZ 3. However, step 2301 can be omitted. Specifically, the air UE 1 can receive the geographical information in advance from the serving RAN node 2 when it is in the RRC_IDLE or RRC_INACTIVE state. Figure 23 The serving RAN node 2 shown receives geographic information about NTZ 3. Alternatively, the airborne UE 1 initiates communication with... Figure 23 Prior to the communication of RAN Node 2 shown, geographical information about NTZ 3 may have been received from different RAN Node 2s.

[0156] In step 2302, the air UE 1 detects its approach to or entry into NTZ 3 based on the geographical information of NTZ 3. The air UE 1 can detect that it is approaching NTZ 3, entering NTZ 3, or has already entered NTZ 3. In step 2303, the air UE 1 transmits a report related to the approach to or entry into NTZ 3 to RAN node 2 of serving cell 21. This report can be transmitted to RAN node 2 of serving cell 21 if serving cell 21 is operating in a frequency band prohibited in NTZ 3.

[0157] Prior to step 2302, the serving RAN node 2 can configure air UE 1 to send a report related to air UE 1 approaching or entering NTZ 3. If serving cell 21 is operating in a frequency band prohibited in NTZ 3, the serving RAN node 2 can configure air UE 1 to send this report.

[0158] For example, to receive reports related to approaching or entering NTZ 3, the serving RAN Node 2 can use the UE Assistance Information procedure. Specifically, the serving RAN Node 2 can use the RRCReconfiguration message to configure the air UE 1 to report UE Assistance Information. The serving RAN Node 2 can configure conditions or events for the air UE 1 to trigger the reporting of UE Assistance Information. In this case, the serving RAN Node 2 configures conditions or events for the air UE 1 to trigger the reporting of UE Assistance Information related to approaching or entering NTZ 3. This condition or event could be that the distance between the air UE 1 and NTZ 3 (or the reference location of NTZ 3) decreases to less than a threshold. Based on the configuration of the serving RAN Node 2, the air UE 1 sends a report related to approaching or entering NTZ 3 as UE Assistance Information to the serving RAN Node 2. That is, the air UE 1 sends this report to the serving RAN Node 2 via the UEAssistanceInformation message.

[0159] In another example, to receive reports related to proximity to or entry into NTZ 3, the serving RAN Node 2 can use a measurement reporting procedure. Specifically, the serving RAN Node 2 can use the RRCReconfiguration message to configure conditions or events for triggering measurement reports for the air UE 1. In this case, the serving RAN Node 2 configures conditions or events for triggering measurement reports related to proximity to or entry into NTZ 3 for the air UE 1. This condition or event could be that the distance between the air UE 1 and NTZ 3 (or a reference location of NTZ 3) decreases to less than a threshold. Based on the configuration of the serving RAN Node 2, the air UE 1 sends a report related to proximity to or entry into NTZ 3 as a measurement report to the serving RAN Node 2. That is, the air UE 1 sends the report to the serving RAN Node 2 via a MeasurementReport message.

[0160] In response to receiving a report relating to approaching or entering NTZ 3, the serving RAN node 2 may perform a procedure or take action to continue uplink communication for air UE 1. For example, as shown in step 2304, based on or in response to receiving a report relating to approaching or entering NTZ 3, the serving RAN node 2 may transfer air UE 1 to another cell operating in a frequency band not prohibited in NTZ 3. Alternatively, the serving RAN node 2 may add another cell operating in a frequency band not prohibited in NTZ 3 as a secondary cell group cell for dual connectivity of the air UE.

[0161] according to Figure 23As shown in the diagram, the airborne UE 1 can use or consider the geographic information of NTZ 3 to send a report to the network related to the airborne UE 1 approaching or entering NTZ 3. This helps to clarify the signaling details related to the mechanisms that enable airborne UEs to comply with NTZ.

[0162] Air UE 1 can use or consider the geographic information of NTZ 3 to transmit a report to RAN node 2 of the serving cell regarding the air UE 1's exit from NTZ 3. Air UE 1 can utilize GNSS positioning information to obtain its location. Figure 24 An example of the operation of UE 1 and RAN node 2 in the air is shown. Figure 24 Assume that the air UE 1 is in the RRC_CONNECTED state. In step 2401, the air UE 1 can receive geographical information from the serving RAN node 2 to define the geographical range of NTZ 3. However, step 2401 can be omitted. Specifically, the air UE 1 can receive the geographical information in advance from the serving RAN node 2 when it is in the RRC_IDLE or RRC_INACTIVE state. Figure 24 The serving RAN node 2 shown receives geographic information about NTZ 3. Alternatively, the airborne UE 1 initiates communication with... Figure 24 Prior to the communication of RAN Node 2 shown, geographical information about NTZ 3 may have been received from different RAN Node 2s.

[0163] In step 2402, the air UE 1 detects its exit from NTZ 3 based on the geographical information of NTZ 3. The air UE 1 can detect whether it is leaving NTZ 3 or has already left NTZ 3. In step 2403, the air UE 1 transmits a report related to its exit from NTZ 3 to RAN node 2 of serving cell 21.

[0164] Prior to step 2402, serving RAN node 2 can configure air UE 1 to send a report related to air UE 1 exiting NTZ 3. Serving cell 21 can be a cell operating in a frequency band not prohibited in NTZ 3. Alternatively, serving cell 21 can be a cell operating in a frequency band prohibited in NTZ 3. In this case, while air UE 1 is still outside NTZ 3, serving RAN node 2 can send the configuration for this report to UE 1 in serving cell 21. Similar to... Figure 23 In the example, Serving RAN Node 2 can utilize the UE Auxiliary Information Procedure or Measurement Report Procedure to receive reports related to exiting NTZ 3.

[0165] In response to receiving a report related to exiting NTZ 3, Serving RAN Node 2 may perform procedures or take actions to restore or restart previous uplink communication of air UE 1. For example, as shown in step 2404, Serving RAN Node 2 may hand over air UE 1 to another cell operating in a frequency band that is prohibited in NTZ 3.

[0166] according to Figure 24 As shown in the diagram, the air UE 1 can use or consider the geographic information of NTZ 3 to send a report to the network related to the air UE 1's exit from NTZ 3. This helps to clarify the signaling details related to the mechanisms that enable air UEs to comply with NTZ.

[0167] The airborne UE 1 can use or consider the geographic information of NTZ 3 for cell selection or cell selection when it is in RRC_IDLE or RRC_INACTIVE state. Figure 25 An example of the operation of airborne UE 1 is illustrated. In step 2501, when airborne UE 1 is in the RRC_IDLE or RRC_INACTIVE state, airborne UE 1 receives NTZ-related information containing geographic information of NTZ 3. In step 2502, airborne UE 1 determines whether it is in NTZ 3. Airborne UE 1 can use GNSS positioning information to obtain its location. In step 2503, if airborne UE 1 is in NTZ 3, airborne UE 1 excludes cells operating in frequency bands prohibited in NTZ 3 from the candidate cells used for cell selection or cell reselection. In other words, if airborne UE 1 is in NTZ 3, airborne UE 1 will consider cells operating in frequency bands prohibited in NTZ 3 as prohibited cells during cell selection or cell reselection.

[0168] according to Figure 25 As shown in the diagram, the air UE 1 can use or consider the geographic information of NTZ 3 for cell selection or cell reselection. This helps to clarify the details regarding how air UEs operate in relation to the mechanisms that make NTZ compliance possible.

[0169] Airborne UE 1 can use or consider the geographic information of NTZ 3 to update the flight path information of airborne UE 1. Figure 26An example of the operation of air UE 1 is illustrated. In step 2601, air UE 1 receives NTZ-related information containing geographic information of NTZ 3. Air UE 1 can receive NTZ-related information when it is in the RRC_IDLE or RRC_INACTIVE state. Alternatively, when air UE 1 is in the RRC_CONNECTED state, air UE 1 can receive NTZ-related information via a dedicated RRC message (e.g., an RRCReconfiguration message).

[0170] In step 2602, the airborne UE 1 updates its flight path information based on NTZ-related information. For example, the airborne UE 1 can update its flight path information to avoid NTZ 3. The flight path information includes multiple waypoints defined as three-dimensional locations.

[0171] Airborne UE 1 can report updated flight path information to the network (e.g., RAN node 2). The triggering conditions for reporting updated flight path information are not specifically limited. For example, the triggering condition could be an update of the flight path information. The triggering condition could be based on a threshold for the number of updated or changed waypoints. Alternatively, the triggering condition could be a periodic trigger based on a timer. Alternatively, the triggering condition could be an event trigger based on distance.

[0172] according to Figure 25 As shown in the diagram, the airborne UE 1 can use or consider the geographic information of NTZ 3 to update its flight path. This helps to clarify the details regarding how airborne UEs operate in relation to the mechanisms that make NTZ compliance possible.

[0173] Airborne UE 1 can use or consider the geographic information of NTZ 3 to send a flight path update notification to the network (e.g., RAN Node 2). In this specification, a flight path update notification can be a notification that flight path information is available. In other words, a flight path update notification may not involve updating the flight path information. Therefore, a flight path update notification can be referred to as a flight path availability notification.

[0174] Figure 27An example of the operation of air UE 1 and RAN node 2 is illustrated. In step 2701, air UE 1 receives geographic information from serving RAN node 2 to define the geographic range of NTZ 3. When air UE 1 is in the RRC_IDLE or RRC_INACTIVE state, air UE 1 can receive geographic information via broadcast in serving cell 21. Alternatively, when air UE 1 is in the RRC_CONNECTED state, air UE 1 can receive geographic information via a UE-specific RRC message (e.g., an RRCReconfiguration message). However, step 2701 can be omitted. Specifically, air UE 1 initiates a connection with... Figure 27 Prior to the communication of RAN Node 2 shown, it may have received the geographical information of NTZ 3 from another RAN Node 2.

[0175] In step 2702, the serving RAN node 2 transmits a configuration to the airborne UE 1 for configuring flight path update notification triggering based on the distance to NTZ 3. In other words, the serving RAN node 2 configures a condition or event for the airborne UE 1 based on the distance to NTZ 3 to trigger the transmission of the flight path update notification. This condition could be that the distance between the airborne UE 1 and NTZ 3 (or the reference position of NTZ 3) falls below a threshold. Alternatively, the condition could be that the distance between the airborne UE 1 and NTZ 3 (or the reference position of NTZ 3) exceeds a threshold. The serving RAN node 2 can broadcast the flight path update notification triggering configuration in cell 21 via system information (e.g., SIB). Alternatively, the serving RAN node 2 can configure the flight path update notification triggering in the airborne UE 1 via a UE-specific RRC message (e.g., an RRCReconfiguration message).

[0176] In step 2703, the air UE 1 detects that the configured trigger condition has been met. In step 2704, in response to the satisfaction of the trigger condition, the air UE 1 transmits a flight path update notification to the serving RAN node 2.

[0177] Flight path update notifications (or flight path availability notifications) can be transmitted via various RRC messages. For example, an airborne UE 1 can indicate to the serving RAN node 2 via the RRCReconfigurationComplete, RRCReestablishmentComplete, RRCResumeComplete, or RRCSetupComplete messages whether the message is a flight path update notification (or flight path availability notification). Additionally or alternatively, UE auxiliary information procedures can be used to transmit flight path update notifications (or flight path availability notifications). Specifically, an airborne UE 1 in the RRC_CONNECTED state can send a flight path update notification or indication to the network via UE auxiliary information messages based on the configuration by the serving RAN node 2.

[0178] As shown in step 2705, upon receiving a flight path update notification (or flight path availability notification), the serving RAN node 2 can request the airborne UE 1 to report flight path information. The serving RAN node 2 can use a UEInformationRequest message to request this information. In response to this request, in step 2706, the airborne UE 1 can transmit the flight path information to the network. The airborne UE 1 can use a UEInformationResponse message to send the flight path information to the network. The flight information may only contain incremental reports (i.e., differences from previous reports).

[0179] according to Figure 27 As illustrated, the airborne UE 1 can use or consider NTZ 3 geographic information to trigger the transmission of a flight path update notification (or flight path availability notification). This helps to clarify the details regarding how airborne UEs operate in relation to the mechanisms that make NTZ compliance possible.

[0180] The following describes example configurations of air UE 1 and RAN node 2 according to the above-described example embodiments. Figure 28A block diagram of an example configuration of over-the-air UE 1 is shown. Radio frequency (RF) transceiver 2801 performs analog RF signal processing to communicate with RAN nodes, including RAN node 2. RF transceiver 2801 may include multiple transceivers. The analog RF signal processing performed by RF transceiver 2801 includes up-conversion, down-conversion, and amplification. RF transceiver 2801 is coupled to antenna array 2802 and baseband processor 2803. RF transceiver 2801 receives modulated symbol data (or orthogonal frequency division multiplexing (OFDM) symbol data) from baseband processor 2803, generates a transmit RF signal, and supplies the transmit RF signal to antenna array 2802. RF transceiver 2801 also generates a baseband receive signal based on the receive RF signal received by antenna array 2802 and supplies the baseband receive signal to baseband processor 2803. RF transceiver 2801 may include analog beamformer circuitry for beamforming. Analog beamformer circuits include, for example, multiple phase shifters and multiple power amplifiers.

[0181] The baseband processor 2803 performs digital baseband signal processing (data plane processing) and control plane processing for radio communications. Digital baseband signal processing includes (a) data compression / decompression, (b) data segmentation / concatenation, (c) transmission format (transmission frame) composition / decomposition, (d) channel coding / decoding, (e) modulation (i.e., symbol mapping) / demodulation, and (f) generating OFDM symbol data (baseband OFDM signals) using inverse fast Fourier transform (IFFT), etc. On the other hand, control plane processing includes communication management at layers 1 (e.g., transmission power control), 2 (e.g., radio resource management and hybrid automatic repeat request (HARQ) processing), and 3 (e.g., signaling related to attach, mobility, and call management).

[0182] For example, digital baseband signal processing performed by baseband processor 2803 may include signal processing for the Serving Data Adaptation Protocol (SDAP) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, Media Access Control (MAC) layer, and Physical (PHY) layer. Control plane processing performed by baseband processor 2803 may include processing of Non-Access Stratum (NAS) protocols, RRC protocols, MAC CE, and Downlink Control Information (DCI).

[0183] The baseband processor 2803 can perform multiple-input multiple-output (MIMO) coding and precoding for beamforming.

[0184] The baseband processor 2803 may include a modem processor (e.g., a digital signal processor (DSP)) for digital baseband signal processing and a protocol stack processor (e.g., a central processing unit (CPU) or microprocessor unit (MPU)) for control plane processing. In this case, the protocol stack processor for control plane processing may be integrated with the application processor 2804, which will be described later.

[0185] Application processor 2804 is also referred to as CPU, MPU, microprocessor, or processor core. Application processor 2804 may include multiple processors (multiple processor cores). Application processor 2804 executes system software programs (operating system (OS)) and various application programs (e.g., call application, web browser, mail transceiver, camera operation application, music player application) read from memory 2806 or unspecified memory, thereby enabling various functions of the over-the-air UE 1.

[0186] In some implementations, such as by Figure 28 As shown by the dashed line (2805), the baseband processor 2803 and application processor 2804 can be integrated on a single chip. In other words, the baseband processor 2803 and application processor 2804 can be implemented as a single system-on-a-chip (SoC) device 2805. SoC devices can also be referred to as system-on-large-scale integration (LSI) or chipsets.

[0187] Memory 2806 is volatile memory, non-volatile memory, or a combination thereof. Memory 2806 may include multiple physically independent memory devices. Volatile memory is, for example, static random access memory (SRAM), dynamic RAM (DRAM), or a combination thereof. Non-volatile memory is, for example, mask read-only memory (MROM), electrically erasable programmable ROM (EEPROM), flash memory, or hard disk drive, or any combination thereof. For example, memory 2806 may include external memory devices accessible by baseband processor 2803, application processor 2804, and SoC 2805. Memory 2806 may also include internal memory devices integrated into baseband processor 2803, application processor 2804, or SoC 2805. Additionally, memory 2806 may include memory within a Universal Integrated Circuit Card (UICC).

[0188] The memory 2806 may store one or more software modules (or computer programs) 2807 including instruction sets and data for processing by the UE 1 described in the above example embodiments. In some implementations, the baseband processor 2803 or application processor 2804 may be configured to read from the memory 2806 and execute the software module 2807 to perform the processing of the UE 1 as described in the example embodiments with reference to the accompanying drawings.

[0189] The control plane processing and operations performed by the UE 1 described in the above example embodiments can be implemented by components other than the RF transceiver 2801 and the antenna array 2802, namely, by at least one of the baseband processor 2803 and the application processor 2804 and the memory 2806 of the storage software module 2807.

[0190] Figure 29 This is a block diagram illustrating an example configuration of RAN node 2 according to the above example embodiment. (See reference) Figure 29 RAN node 2 includes an RF transceiver 2901, a network interface 2903, a processor 2904, and a memory 2905. The RF transceiver 2901 performs analog RF signal processing to communicate with UEs, including UE 1. The RF transceiver 2901 may include multiple transceivers. The RF transceiver 2901 is coupled to an antenna array 2902 and a processor 2904. The RF transceiver 2901 receives modulation symbol data from the processor 2904, generates a transmission RF signal, and supplies the transmission RF signal to the antenna array 2902. The RF transceiver 2901 generates a baseband receive signal based on the received RF signal received by the antenna array 2902 and supplies the baseband receive signal to the processor 2904. The RF transceiver 2901 may include analog beamformer circuitry for beamforming. The analog beamformer circuitry includes, for example, multiple phase shifters and multiple power amplifiers.

[0191] Network interface 2903 is used to communicate with network nodes (e.g., other RAN nodes, as well as control and transport nodes in the core network). For example, network interface 2903 may include a network interface card (NIC) compliant with the IEEE 802.3 family.

[0192] Processor 2904 performs digital baseband signal processing (data plane processing) and control plane processing for radio communications. Processor 2904 may include multiple processors. For example, processor 2904 may include a modem processor (e.g., DSP) for digital baseband signal processing and a protocol stack processor (e.g., CPU or MPU) for control plane processing.

[0193] For example, digital baseband signal processing performed by processor 2904 may include signal processing for SDAP, PDCP, radio RLC, MAC, and PHY layers. Control plane processing performed by processor 2904 may include processing of NAS messages, RRC messages, MAC CE, and DCI.

[0194] The processor 2904 may include a digital beamformer module for beamforming. The digital beamformer module may include a MIMO encoder and a pre-encoder.

[0195] Memory 2905 comprises a combination of volatile and non-volatile memory. Volatile memory may be, for example, SRAM or DRAM, or a combination thereof. Non-volatile memory may be MROM, EEPROM, flash memory, or hard disk drive, or any combination thereof. Memory 2905 may include a storage device configured separately from processor 2904. In this case, processor 2904 may access memory 2905 via network interface 2903 or an I / O interface not illustrated.

[0196] Memory 2905 may store one or more software modules (computer programs) 2906 containing instructions and data for processing by the RAN node 2 described in the above example embodiments. In some implementations, processor 2904 may be configured to execute software module 2906 read from memory 2905 to perform the processing of RAN node 2 described in the above example embodiments.

[0197] In the case that RAN node 2 is a CU (e.g., eNB-CU or gNB-CU) or CU-CP, RAN node 2 may not include RF transceiver 2901 (and antenna array 2902) and LP-WUS transmitter 1810.

[0198] If used Figure 28 and Figure 29 As explained, the processors of the airborne UE 1 and RAN node 2 in the above example embodiments can each execute one or more programs containing instruction sets to cause the computer to perform the algorithms described with reference to the accompanying drawings. Each of these programs contains an instruction set (or software code) that, if loaded into the computer, causes the computer to perform one or more of the functions described in the example embodiments. Each of these programs can be stored in a non-transitory computer-readable medium or tangible storage medium. By way of example, and not limitation, the non-transitory computer-readable medium or tangible storage medium may include random access memory (RAM), read-only memory (ROM), flash memory, solid-state drives (SSDs) or other memory technologies, CD-ROMs, digital versatile discs (DVDs), Blu-ray discs or other optical disc storage, magnetic tape cassettes, magnetic tapes, disk storage, or other magnetic storage devices. Each program can be transmitted on a transient computer-readable medium or communication medium. By way of example, and not limitation, the transient computer-readable medium or communication medium may include electrical, optical, acoustic, or other forms of propagated signals.

[0199] The above examples are merely illustrative of the application of technical concepts obtained by the inventors. These technical concepts are not limited to the above examples and can be modified in various ways.

[0200] For example, all or part of the exemplary embodiments disclosed above may be described as, but not limited to, the following supplementary descriptions. Of course, all or part of the elements (e.g., configuration and functionality) described in the supplementary descriptions for devices (e.g., air UEs or RAN nodes) may also be described as supplementary descriptions for methods and procedures, or described in supplementary descriptions for methods and procedures. For example, all or part of the elements listed in Supplementary Descriptions 2-22 that depend on Supplementary Description 1 may also be listed as supplementary descriptions that depend on Supplementary Descriptions 43 or 45 having the same dependencies as Supplementary Descriptions 2-22. Similarly, all or part of the elements listed in Supplementary Descriptions 24-42 that depend on Supplementary Description 23 may also be listed as supplementary descriptions that depend on Supplementary Descriptions 44 or 46 having the same dependencies as Supplementary Descriptions 24-42. All or part of the elements described in the supplementary descriptions may be applicable to various hardware, software, storage devices for storing software, systems, and methods.

[0201] (Supplementary Note 1)

[0202] An airborne user equipment, or airborne UE, includes:

[0203] A component for receiving NTZ-related information from the network in the first cell, which includes geographic information for defining the geographic range of the prohibited transmission zone (NTZ) for airborne UEs.

[0204] (Supplementary Note 2)

[0205] According to Supplementary Note 1, the airborne UE, wherein the NTZ related information further includes information indicating one or more frequency bands in which transmission by the airborne UE is not permitted in the NTZ.

[0206] (Supplementary Note 3)

[0207] According to Supplementary Note 1 or 2, the airborne UE, wherein the geographic information includes latitude and longitude information for defining the location and extent of the geographic range.

[0208] (Supplementary Note 4)

[0209] According to any one of Supplementary Notes 1 to 3, the airborne UE, wherein the component for receiving is adapted to receive the NTZ-related information via a Radio Resource Control (RRC) message dedicated to the airborne UE or via system information common within the first cell.

[0210] (Supplementary Note 5)

[0211] According to any one of Supplementary Notes 1 to 4, the airborne UE further includes components for transmitting a first report related to approaching or entering the NTZ to the RAN node of the first serving cell based on the NTZ-related information.

[0212] (Supplementary Note 6)

[0213] According to the air UE in Supplementary Note 5, the component for transmission is adapted to transmit the first report to the RAN node of the first serving cell if the first serving cell is operating in a frequency band that is prohibited in the NTZ.

[0214] (Supplementary Note 7)

[0215] According to Supplementary Note 5 or 6, the air UE is provided in which the first report causes the RAN node to transfer the air UE to another cell that operates in a frequency band not prohibited in the NTZ, or to add the other cell as a secondary cell group cell for the dual connectivity of the air UE.

[0216] (Supplementary Note 8)

[0217] According to any one of Supplementary Notes 5 to 7, the airborne UE wherein the component for transmission is adapted to transmit the first report via an RRC message.

[0218] (Supplementary Note 9)

[0219] According to Supplementary Note 8, the airborne UE, wherein the RRC message carrying the first report is a UEAssistanceInformation message or a MeasurementReport message.

[0220] (Supplementary Note 10)

[0221] According to any one of Supplementary Notes 5 to 9, the airborne UE, wherein the first serving cell is the same as the first cell.

[0222] (Supplementary Note 11)

[0223] According to any one of Supplementary Notes 1 to 10, the airborne UE further includes a component for transmitting a second report relating to exiting the NTZ to the RAN node of the second serving cell based on the NTZ-related information.

[0224] (Supplementary Note 12)

[0225] According to the airborne UE described in Supplementary Note 11, the second serving cell is a cell operating in a frequency band that is not prohibited in the NTZ.

[0226] (Supplementary Note 13)

[0227] According to Supplementary Note 12, the air UE is described in which the second report causes the RAN node of the second serving cell to transfer the air UE to another cell operating in a frequency band that is prohibited in the NTZ.

[0228] (Supplementary Note 14)

[0229] According to any one of Supplementary Notes 11 to 13, the airborne UE wherein the component for transmitting the second report is adapted to transmit the second report via an RRC message.

[0230] (Supplementary Note 15)

[0231] According to Supplementary Note 14, the airborne UE, wherein the RRC message carrying the second report is a UEAssistanceInformation message or a MeasurementReport message.

[0232] (Supplementary Note 16)

[0233] According to any one of Supplementary Notes 11 to 15, the airborne UE, wherein the second serving cell is different from the first cell.

[0234] (Supplementary Note 17)

[0235] According to any one of Supplementary Notes 1 to 16, the airborne UE further includes a component for treating cells operating in frequency bands prohibited in the NTZ as prohibited cells during cell selection or cell reselection based on NTZ-related information if the airborne UE is within the NTZ.

[0236] (Supplementary Note 18)

[0237] According to any one of Supplementary Notes 1 to 17, the airborne UE also includes components for updating the flight path information of the airborne UE based on the NTZ-related information.

[0238] (Supplementary Note 19)

[0239] According to the airborne UE described in Supplementary Note 18, the flight path information includes multiple waypoints, each of which is defined as a three-dimensional position.

[0240] (Supplementary Note 20)

[0241] According to any one of Supplementary Notes 1 to 19, the airborne UE further includes components for transmitting a flight path update notification to the network in response to determining proximity to the NTZ based on the NTZ-related information.

[0242] (Supplementary Note 21)

[0243] According to the airborne UE as described in Supplementary Note 20, the component for transmitting the flight path update notification is adapted to transmit the flight path update notification via a UE auxiliary information message.

[0244] (Supplementary Note 22)

[0245] According to the airborne UE described in Supplementary Note 20, the component for transmitting the flight path update notification is adapted to transmit the flight path update notification via an RRCReconfigurationComplete, RRCReestablishmentComplete, RRCResumeComplete, or RRCSetupComplete message.

[0246] (Supplementary Note 23)

[0247] A radio access network node, or RAN node, includes:

[0248] A component for transmitting NTZ-related information, which includes geographic information for defining the geographic range of the prohibited transmission zone (NTZ) for the airborne UE, to an airborne UE in the first cell.

[0249] (Supplementary Note 24)

[0250] According to the RAN node described in Supplementary Note 23, the NTZ-related information further includes information indicating one or more frequency bands in which transmission by an over-the-air UE is not permitted in the NTZ.

[0251] (Supplementary Note 25)

[0252] According to the RAN node described in Supplementary Note 13 or 24, the geographic information includes latitude and longitude information for defining the location and extent of the geographic range.

[0253] (Supplementary Note 26)

[0254] According to any one of Supplementary Notes 23 to 25, the RAN node used for transmission is adapted to transmit the NTZ-related information via Radio Resource Control (RRC) messages dedicated to the airborne UE or via system information common within the first cell.

[0255] (Supplementary Note 27)

[0256] According to any one of Supplementary Notes 23 to 26, the RAN node further includes components for configuring the air UE to transmit a first report related to approaching or entering the NTZ, determined based on the NTZ-related information.

[0257] (Supplementary Note 28)

[0258] According to the RAN node in Supplementary Note 27, the component for configuration is adapted to configure the air UE to transmit the first report if the first cell operates in a frequency band that is prohibited in the NTZ.

[0259] (Supplementary Note 29)

[0260] According to Supplementary Note 27 or 28, the RAN node also includes components for transferring the air UE to another cell operating in a frequency band not prohibited in the NTZ based on the first report, or for adding the other cell as a secondary cell group cell for the dual connectivity of the air UE.

[0261] (Supplementary Note 30)

[0262] The RAN node according to any one of Supplementary Notes 27 to 29 further includes components for receiving the first report via RRC messages.

[0263] (Supplementary Note 31)

[0264] According to the RAN node described in Supplementary Note 30, the RRC message carrying the first report is a UEAssistanceInformation message or a MeasurementReport message.

[0265] (Supplementary Note 32)

[0266] According to any one of Supplementary Notes 23 to 31, the RAN node further includes a component for configuring the air UE to transmit a second report related to exiting the NTZ, determined based on the NTZ-related information.

[0267] (Supplementary Explanation 33)

[0268] The RAN node, as described in Supplementary Note 32, also includes components for transferring the airborne UE to another cell operating in a frequency band prohibited in the NTZ based on the second report.

[0269] (Supplementary Note 34)

[0270] According to the RAN node described in Supplementary Note 32 or 33, the component for receiving the second report is adapted to receive the second report transmitted via RRC messages.

[0271] (Supplementary Note 35)

[0272] According to the RAN node described in Supplementary Note 34, the RRC message carrying the second report is a UEAssistanceInformation message or a MeasurementReport message.

[0273] (Supplementary Explanation 36)

[0274] According to any one of Supplementary Notes 23 to 35, for any RAN node, if the air UE is within the NTZ, the NTZ-related information causes the air UE to consider cells operating in frequency bands prohibited in the NTZ as prohibited cells during cell selection or cell reselection.

[0275] (Supplementary Note 37)

[0276] According to any one of Supplementary Notes 23 to 36, the RAN node, wherein the NTZ related information causes the airborne UE to update the airborne UE's flight path information.

[0277] (Supplementary Note 38)

[0278] According to the RAN node described in Supplementary Note 37, the flight path information includes multiple waypoints, each of which is defined as a three-dimensional location.

[0279] (Supplementary Note 39)

[0280] According to any one of Supplementary Notes 23 to 38, the RAN node, wherein the NTZ-related information causes the airborne UE to transmit a flight path update notification to the network in response to determining proximity to the NTZ.

[0281] (Supplementary Note 40)

[0282] The RAN node described in Supplementary Note 39 also includes components for receiving the flight path update notification from the airborne UE.

[0283] (Supplementary Note 41)

[0284] According to the RAN node described in Supplementary Note 40, the component for receiving the flight path update notification is adapted to receive the flight path update notification via a UEAssistanceInformation message.

[0285] (Supplementary Note 42)

[0286] According to the RAN node described in Supplementary Note 40, the component for receiving the flight path update notification is adapted to receive the flight path update notification via an RRCReconfigurationComplete, RRCReestablishmentComplete, RRCResumeComplete, or RRCSetupComplete message.

[0287] (Supplementary Note 43)

[0288] A method performed by an over-the-air user equipment (UE), the method comprising:

[0289] In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for airborne UEs is received from the network.

[0290] (Supplementary Note 44)

[0291] A method performed by a radio access network node, i.e., a RAN node, the method comprising:

[0292] In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for the airborne UE is transmitted to the airborne UE.

[0293] (Supplementary Note 45)

[0294] A program for enabling a computer to perform a method for an airborne user equipment, i.e., an airborne UE, said method comprising:

[0295] In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for airborne UEs is received from the network.

[0296] (Supplementary Explanation 46)

[0297] A program for enabling a computer to perform a method for a radio access network node, i.e., a RAN node, said method comprising:

[0298] In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for the airborne UE is transmitted to the airborne UE.

[0299] This application is based on and claims the priority of Japanese Patent Application No. 2023-139933, filed on August 30, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0300] List of reference numerals

[0301] 1. Airborne UE

[0302] 2. 2A-2G RAN Nodes

[0303] 21, 21A-21G Community

[0304] 3. No Transmission Zone (NTZ)

[0305] 22. Central Unit (CU)

[0306] 23. 23A-23C Distributed Unit (DU)

Claims

1. An over-the-air user equipment, i.e., an over-the-air UE, comprising: A component for receiving NTZ-related information from the network in the first cell, which includes geographic information for defining the geographic range of the prohibited transmission zone (NTZ) for airborne UEs.

2. The airborne UE according to claim 1, wherein, The NTZ-related information also includes information indicating one or more frequency bands in which transmission by an over-the-air UE is not permitted in the NTZ.

3. The airborne UE according to claim 1 or 2, wherein, The geographic information includes latitude and longitude information used to define the location and extent of the geographic area.

4. The airborne UE according to any one of claims 1 to 3, wherein, The receiving component is adapted to receive the NTZ-related information via Radio Resource Control (RRC) messages dedicated to the airborne UE or via system information common within the first cell.

5. The airborne UE according to any one of claims 1 to 4, further comprising a component for transmitting a first report relating to proximity to or entry into the NTZ to the RAN node of the first serving cell based on the NTZ-related information.

6. The airborne UE according to claim 5, wherein, The first report causes the RAN node to transfer the air UE to another cell operating in a frequency band that is not prohibited in the NTZ, or to add the other cell as a secondary cell group cell for the air UE's dual connectivity.

7. The airborne UE according to any one of claims 1 to 6, further comprising a component for transmitting a second report relating to exit from the NTZ to the RAN node of the second serving cell based on the NTZ-related information.

8. The airborne UE according to any one of claims 1 to 7, further comprising a component for treating cells operating in frequency bands prohibited in the NTZ as prohibited cells during cell selection or cell reselection based on NTZ-related information if the airborne UE is within the NTZ.

9. The airborne UE according to any one of claims 1 to 8, further comprising a component for updating the flight path information of the airborne UE based on the NTZ related information.

10. The airborne UE according to any one of claims 1 to 9, further comprising a component for transmitting a flight path update notification to the network in response to determining proximity to the NTZ based on the NTZ-related information.

11. A radio access network node, i.e., a RAN node, comprising: A component for transmitting NTZ-related information, which includes geographic information for defining the geographic range of the prohibited transmission zone (NTZ) for the airborne UE, to an airborne UE in the first cell.

12. The RAN node according to claim 11, wherein, The NTZ-related information also includes information indicating one or more frequency bands in which transmission by an over-the-air UE is not permitted in the NTZ.

13. The RAN node according to claim 11 or 12, wherein, The geographic information includes latitude and longitude information used to define the location and extent of the geographic area.

14. The RAN node according to any one of claims 11 to 13, wherein, The components used for transmission are adapted to transmit the NTZ-related information via Radio Resource Control (RRC) messages dedicated to the airborne UE or via system information common within the first cell.

15. The RAN node according to any one of claims 11 to 14, further comprising a component for configuring the airborne UE to transmit a first report related to proximity to or entry into the NTZ, determined based on the NTZ-related information.

16. The RAN node of claim 15, further comprising components for transferring the air UE to another cell operating in a frequency band not prohibited in the NTZ based on the first report, or for adding the other cell as a secondary cell group cell for dual connectivity of the air UE.

17. The RAN node according to any one of claims 11 to 16, further comprising a component for configuring the air UE to transmit a second report related to exiting the NTZ, determined based on the NTZ-related information.

18. The RAN node according to any one of claims 11 to 17, wherein, If the air UE is within the NTZ, the NTZ-related information causes the air UE to treat cells operating in frequency bands prohibited in the NTZ as prohibited cells during cell selection or cell reselection.

19. The RAN node according to any one of claims 11 to 18, wherein, The NTZ-related information enables the airborne UE to update its flight path information.

20. The RAN node according to any one of claims 11 to 19, wherein, The NTZ-related information causes the airborne UE to transmit a flight path update notification to the network in response to determining its approach to the NTZ.

21. A method performed by an over-the-air user equipment (UE), the method comprising: In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for airborne UEs is received from the network.

22. A method performed by a radio access network node, i.e., a RAN node, the method comprising: In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for the airborne UE is transmitted to the airborne UE.

23. A program for causing a computer to perform a method for an airborne user equipment, i.e., an airborne UE, said method comprising: In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for airborne UEs is received from the network.

24. A program for causing a computer to perform a method for a radio access network node, i.e., a RAN node, said method comprising: In the first cell, NTZ-related information containing geographic information used to define the geographic range of the no-transmission zone (NTZ) for the airborne UE is transmitted to the airborne UE.

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