Method and apparatus for optimizing intermobility between distributed radio access network nodes

Abstract

[0003] The present disclosure relates to data communications. Particular embodiments provide a user equipment (UE) (110) for accessing a radio access network (RAN) (100), the user equipment (UE) comprising at least a central node (210) and a distributed node (220), the central node controlling the distributed node, the user equipment (UE) comprising at least one processor (12) and at least one memory (13) storing instructions (14), which, when executed by the at least one processor, cause the user equipment (UE) to at least establish a connection to the radio access network, receive from the central node a UE context modification request, the UE context modification request including a request to change at least a portion of a lower layer configuration and an identifier associated with the request, implement the requested change of the lower layer configuration (502), send a confirmation that the requested change has been implemented toward the central node (504), and send the identifier toward the distributed node (505).

Description

[Technical Field]

[0001] Various embodiments of the present disclosure relate to the field of data communications, and in particular to user equipment, distributed nodes, central nodes, and systems for data communications. Without prejudice to the above, particular embodiments relate to user equipment, distributed nodes, central nodes, and systems for use in Layer 1 / Layer 2-based inter-cell mobility within a radio access network. [Background technology]

[0002] During traditional intra-gNB-Central Unit (CU) mobility in a Radio Access Network (RAN), a User Equipment (UE) moves from one cell of a gNB-CU to another cell of the gNB-CU. During traditional intra-gNB-CU mobility, a gNB-Distributed Unit (gNB-DU) of a gNB-CU currently serving the UE hands over the UE's serving to a new gNB-DU of the gNB-CU that will begin serving the UE. An intra-gNB-CU handover (HO) procedure (also referred to as an inter-gNB-DU HO procedure) is performed to perform intra-gNB-CU mobility (also referred to as inter-gNB-DU mobility).

[0003] Conventional intra-gNB-CU (inter-gNB-DU) HO procedures are not always optimal.

[0004] In some situations, it may be desirable to provide improved data communications, particularly in the case of intra-gNB-CU mobility.

[0005] The listing or discussion of any previously published document or any background in this specification should not necessarily be taken as an acknowledgement that the document or background is part of the state of the art or is common general knowledge. One or more aspects / embodiments of the present disclosure may or may not address one or more of the issues in the background. Summary of the Invention

[0006] The scope of protection sought for various embodiments of the invention is set forth in the claims.

[0007] In accordance with various, but not necessarily all, embodiments of the present disclosure, examples are provided as claimed in the accompanying claims. Any examples and features described herein that do not fall within the scope of an independent claim are to be construed as examples useful for understanding various embodiments of the present invention.

[0008] According to at least some embodiments of the present disclosure, there is provided a radio access network, a user equipment (UE) for accessing a radio access network (RAN), comprising at least a central node and distributed nodes, the central node controlling the distributed nodes, and the UE: at least one processor; at least one memory for storing instructions; the instructions, when executed by the at least one processor, cause the UE to establishing a connection towards a radio access network; A UE context modification request from a central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, including: implementing the requested changes in lower layer configuration; sending a confirmation to the central node that the requested changes have been implemented; Sending the identifier to the distributed node; Make them do so.

[0009] In accordance with various, but not necessarily all, embodiments of the present disclosure, a method for a user equipment, UE, is provided, the method comprising: Establishing a connection towards a Radio Access Network (RAN), the RAN comprising at least a central node and distributed nodes, the central node controlling the distributed nodes; A UE context modification request from a central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, including: implementing the requested changes in lower layer configuration; sending a confirmation to the central node that the requested changes have been implemented; Sending the identifier to the distributed node; This includes at least partially causing an action that results in

[0010] In accordance with various, though not necessarily all, embodiments of the present disclosure, a chipset is provided that includes processing circuitry configured to implement the methods described above.

[0011] According to various, though not necessarily all, embodiments of the present disclosure, there are provided modules, circuitry, devices, and / or systems comprising means for performing the methods described above.

[0012] According to various, though not necessarily all, embodiments of the present disclosure, a computer program product is provided that includes instructions that, when executed by an apparatus, cause the apparatus to perform the methods described above.

[0013] In accordance with various, though not necessarily all, embodiments of the present disclosure, a non-transitory computer-readable medium is provided that is encoded with instructions that, when executed by at least one processor, cause at least the following to be performed in accordance with the methods described above:

[0014] According to at least some embodiments of the present disclosure, There is provided a user equipment (UE) for accessing a radio access network (RAN), comprising at least a central node and distributed nodes, wherein the central node controls the distributed nodes, and the UE: means for establishing a connection towards a radio access network; A UE context modification request from a central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request means for receiving a UE context modification request, comprising: means for implementing the requested change in lower layer configuration; means for transmitting a confirmation to the central node that the requested change has been implemented; means for transmitting the identifier to a distributed node; Equipped with.

[0015] The remainder of this "Brief Summary" section describes, mutatis mutandis, various features that may be characteristic of any of the embodiments described in the preceding portion of this "Brief Summary" section. The description of a function should also be considered to disclose any suitable means for implementing that function.

[0016] In some, but not necessarily all, embodiments, the UE context modification request includes: Layer 3 protocol messages, Radio Resource Configuration (RRC) messages, and RRC Reconfiguration Message is received from the central node in one selected from the group:

[0017] In some, but not necessarily all, embodiments, the identifier is: Through Layer 2 signaling, In Layer 2 protocol messages, and Medium Access Control (MAC), Control Element (CE) , which is one selected from the group of , and is sent towards the distributed node.

[0018] In some, but not necessarily all, embodiments, the identifier is: Through Layer 1 signaling, Uplink Control Information (UCI) Channel State Information, CSI, reports, and Layer 1 measurement report , which is one selected from the group of , and is sent towards the distributed node.

[0019] In some, but not necessarily all, embodiments, the UE context modification request includes an indicator for the UE to request the UE to confirm to the distributed node that the UE has implemented the requested changes, and the UE is further configured to, based at least in part on the received indicator, send an indicator to the distributed node to confirm to the distributed node that the UE has implemented the requested changes.

[0020] In some, but not necessarily all, embodiments, the indicator is a flag or identifier.

[0021] In some, but not necessarily all, embodiments, the identifier is: An identifier to identify the request, a multi-bit identifier, or Flags is.

[0022] In some, but not necessarily all, embodiments, the requested change is: Reconfiguring a lower layer protocol of the UE; Coordinating Layer 1, L1, measurements performed by the UE; and Reconstructing a L1 measurement report of the UE; measuring one or more beams of the target cell; reporting one or more measurements of one or more beams of the target cell; The request includes a request made by the UE to at least one selected from the group consisting of:

[0023] According to at least some embodiments of the present disclosure, there is provided a radio access network (RAN) comprising at least a central node and a distributed node, the distributed node of the RAN, wherein the central node controls the distributed node, and the distributed node: at least one processor; at least one memory for storing instructions; The instructions, when executed by the at least one processor, cause the distributed node to perform at least A first user equipment, UE, context modification request sent from a central node towards a distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a first UE context modification request, a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and identifier receiving a second UE context modification request, sending a second UE context modification request to the UE; receiving an identifier from the UE; Make them do so.

[0024] In accordance with at least some embodiments of the present disclosure, a method for distributed nodes in a radio access network (RAN) is provided, the RAN comprising at least a central node and distributed nodes, the central node controlling the distributed nodes, the method comprising: A first user equipment, UE, context modification request sent from a central node towards a distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a first UE context modification request, a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and identifier receiving a second UE context modification request, sending a second UE context modification request to the UE; receiving an identifier from the UE; This includes at least partially causing an action that results in

[0025] In accordance with various, though not necessarily all, embodiments of the present disclosure, a chipset is provided that includes processing circuitry configured to implement the methods described above.

[0026] According to various, though not necessarily all, embodiments of the present disclosure, there are provided modules, circuitry, devices, and / or systems comprising means for performing the methods described above.

[0027] According to various, though not necessarily all, embodiments of the present disclosure, a computer program product is provided that includes instructions that, when executed by an apparatus, cause the apparatus to perform the methods described above.

[0028] In accordance with various, though not necessarily all, embodiments of the present disclosure, a non-transitory computer-readable medium is provided that is encoded with instructions that, when executed by at least one processor, cause at least the following to be performed in accordance with the methods described above:

[0029] According to at least some embodiments of the present disclosure, there is provided a radio access network (RAN) comprising at least a central node and a distributed node, the distributed node of the RAN, wherein the central node controls the distributed node, and the distributed node: A first user equipment, UE, context modification request sent from a central node towards a distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request means for receiving a first UE context modification request, comprising: a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and identifier means for receiving a second UE context modification request, comprising: means for sending a second UE context modification request to the UE; means for receiving an identifier from the UE; Equipped with.

[0030] The remainder of this "Summary of the Invention" section describes, mutatis mutandis, various features that may be characteristic of any of the embodiments described in the preceding portion of the "Summary of the Invention" section. The description of a function should also be considered to disclose any suitable means for implementing that function.

[0031] In some, but not necessarily all, embodiments, the distributed node is further configured to determine that the UE has implemented the requested change based at least in part on the identifier received from the UE.

[0032] In some, but not necessarily all, embodiments, the distributed node is further configured to transmit a response to the first UE context modification request towards the central node.

[0033] In some, but not necessarily all, embodiments, the response to the first UE context modification request includes an identifier or exchange identifier to identify the request.

[0034] In some, but not necessarily all, embodiments, the distributed node: receiving a confirmation from the UE for transmission towards the central node that the requested change has been implemented; Sending a confirmation to the central node The device is further configured to:

[0035] In some, but not necessarily all, embodiments, the first UE context modification request includes: Reconfiguring a lower layer protocol of the UE; Coordinating interpretation of Layer 1, L1, measurement reports received from the UE; receiving L1 measurements from the UE for the target cell; Associating one or more measurements from a measurement report received from the UE with one or more beams of the target cell; UE, a target cell controlled by a distributed node; a target cell controlled by another distributed node; and One or more candidate target cells and handing over to at least one selected from the group The request includes a request to perform at least one or more of the following:

[0036] In some, but not necessarily all, embodiments, the first UE context modification request includes multiple requested changes to lower layer configurations; the identifier is configured to distinguish between multiple requested modifications; or The identifiers include a plurality of identifiers configured to identify a plurality of requested modifications, respectively.

[0037] In some, but not necessarily all, embodiments, the distributed node: and / or adjusting the interpretation of Layer 1, L1, measurement reports received from the UE based at least in part on the identifier received from the central node. The node is further configured to associate, based at least in part on the identifier received from the central node, one or more measurements from the measurement report received from the UE with one or more beams of the target cell.

[0038] In some, but not necessarily all, embodiments, the distributed node determines, based at least in part on the identifier received from the UE, that one or more L1 measurements received from the UE: target cell, one or more candidate target cells; one or more beams of the target cell; and One or more beams of one or more candidate target cells The method is further configured to determine whether the selected one of the following is associated with at least one selected from the group:

[0039] In some, but not necessarily all, embodiments, the distributed node: an identifier received from the UE; and a L1 measurement report received from the UE following receipt of the identifier from the UE; the group of: determining to trigger the UE to perform a handover of the UE to the target cell based at least in part on at least one selected from the group of:

[0040] In some, but not necessarily all, embodiments, the second UE context modification request includes: Layer 3 protocol messages, Radio resource configuration, RRC,messages, and, RRC Reconfiguration Message is received from the central node in one selected from the group:

[0041] In some, but not necessarily all, embodiments, the identifier is: Through Layer 2 signaling, In Layer 2 protocol messages, and Medium Access Control, MAC, Control Element, CE and received from the EU.

[0042] In some, but not necessarily all, embodiments, the identifier is: Through Layer 1 signaling, Uplink Control Information (UCI) Channel state information, in CSI reports, and Layer 1 measurement report and received from the UE.

[0043] In some, but not necessarily all, embodiments, the second UE context modification request includes an indicator for requesting the UE to confirm to the distributed node that the UE has implemented the requested changes, and the distributed node is further configured to receive from the UE an indicator for the UE to confirm to the distributed node that the UE has implemented the requested changes.

[0044] In some, but not necessarily all, embodiments, the indicator is a flag or identifier.

[0045] In some, but not necessarily all, embodiments, the identifier is: An identifier to identify the request, a multi-bit identifier, or Flags is.

[0046] In some, but not necessarily all, embodiments, the requested changes in the second UE context modification request include: Reconfiguring a lower layer protocol of the UE; Coordinating Layer 1, L1, measurements performed by the UE; and Reconstructing a L1 measurement report of the UE; measuring one or more beams of the target cell; reporting one or more measurements of one or more beams of the target cell; The request includes a request made by the UE to at least one selected from the group consisting of:

[0047] According to at least some embodiments of the present disclosure, there is provided a radio access network (RAN) comprising at least a central node and distributed nodes, the central node of the RAN controlling the distributed nodes, the central node comprising: at least one processor; at least one memory for storing instructions; The instructions, when executed by the at least one processor, cause the distributed node to perform at least generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: A request to modify at least a portion of the lower layer; and identifier a first user equipment, UE, sending a context modification request towards a distributed node; A second UE context modification request, A request to change at least a portion of the lower layer configuration; and identifier sending a second UE context modification request to the UE, the second UE context modification request including: Make them do so.

[0048] According to at least some embodiments of the present disclosure, there is provided a method for a radio access network (RAN) comprising at least a central node and distributed nodes, the central node controlling the distributed nodes, the method comprising: generating an identifier associated with a request to modify at least a portion of a lower layer; A first user equipment (UE) context modification request, comprising: A request to modify at least a portion of the lower layer; and identifier sending a first UE context modification request towards the distributed node, comprising: A second UE context modification request, A request to change at least a portion of the lower layer configuration; and identifier sending a second UE context modification request to the UE, the second UE context modification request including: Includes.

[0049] In accordance with various, though not necessarily all, embodiments of the present disclosure, a chipset is provided that includes processing circuitry configured to implement the methods described above.

[0050] According to various, though not necessarily all, embodiments of the present disclosure, there are provided modules, circuitry, devices, and / or systems comprising means for performing the methods described above.

[0051] According to various, though not necessarily all, embodiments of the present disclosure, a computer program product is provided that includes instructions that, when executed by an apparatus, cause the apparatus to perform the methods described above.

[0052] In accordance with various, though not necessarily all, embodiments of the present disclosure, a non-transitory computer-readable medium is provided that is encoded with instructions that, when executed by at least one processor, cause at least the following to be performed in accordance with the methods described above:

[0053] According to at least some embodiments of the present disclosure, there is provided a radio access network (RAN) comprising at least a central node and distributed nodes, the central node of the RAN controlling the distributed nodes, the central node comprising: means for generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: A request to modify at least a portion of the lower layer; and identifier a first user equipment (UE) means for transmitting a context modification request towards a distributed node; A second UE context modification request, A request to change at least a portion of the lower layer configuration; and identifier means for transmitting a second UE context modification request to the UE, the second UE context modification request including: Equipped with.

[0054] The remainder of this "Summary of the Invention" section describes, mutatis mutandis, various features that may be characteristic of any of the embodiments described in the preceding portion of the "Summary of the Invention" section. The description of a function should also be considered to disclose any suitable means for implementing that function.

[0055] In some, but not necessarily all, embodiments, the central node is further configured to receive a response to the first UE context modification request from the distributed node.

[0056] In some, but not necessarily all, embodiments, the response to the first UE context modification request includes an identifier or exchange identifier to identify the request.

[0057] In some, but not necessarily all, embodiments, the central node is further configured to receive confirmation from the UE that the requested changes have been implemented.

[0058] In some, but not necessarily all, embodiments, the first UE context modification request includes: Reconfiguring a lower layer protocol of the distributed node; Coordinating interpretation of Layer 1, L1, measurement reports received from the UE; receiving L1 measurements for a target cell from the UE; Associating one or more measurements from a measurement report received from the UE with one or more beams of the target cell; The UE is then sent from the cell of the distributed node to a target cell, and One or more candidate target cells and handing over to at least one selected from the group The request includes a request to perform at least one or more of the following:

[0059] In some, but not necessarily all, embodiments, the first UE context modification request includes multiple requested changes to lower layer configurations; the identifier is configured to distinguish between multiple requested modifications; or The identifiers include a plurality of identifiers configured to identify a plurality of requested modifications, respectively.

[0060] In some, but not necessarily all, embodiments, the second UE context modification request includes: Layer 3 protocol messages, Radio resource configuration, RRC,messages, and, RRC Reconfiguration Message is transmitted to the UE in one selected from the group:

[0061] In some, but not necessarily all, embodiments, the second UE context modification request includes an indicator to request the UE to confirm to the distributed node that the UE has implemented the requested changes.

[0062] In some, but not necessarily all, embodiments, the indicator is a flag or identifier.

[0063] In some, but not necessarily all, embodiments, the identifier is: An identifier to identify the request, a multi-bit identifier, or Flags is.

[0064] In some, but not necessarily all, embodiments, the requested changes in the second UE context modification request include: Reconfiguring a lower layer protocol of the UE; adjusting Layer 1, L1, measurements performed by the UE; and Reconstructing a L1 measurement report of the UE; measuring one or more beams of the target cell; reporting one or more measurements of one or more beams of the target cell; The request includes a request made by the UE to at least one selected from the group consisting of:

[0065] While the above-described exemplary and optional features of the present disclosure are described separately, it is understood that their provision in all possible combinations and permutations is included within the present disclosure. It is understood that various exemplary embodiments of the present disclosure may include any or all of the features described with respect to other exemplary embodiments of the present disclosure, and vice versa. Likewise, it is understood that any one or more or all of the features may be performed by / included in / enabled by apparatus, methods, and / or computer program instructions, in any combination, as desired and appropriate.

[0066] Some embodiments will now be described with reference to the accompanying drawings. [Brief explanation of the drawings]

[0067] [Figure 1]FIG. 1 illustrates an example of the subject matter described herein. [Figure 2] FIG. 1 illustrates another example of the subject matter described herein. [Figure 3] FIG. 1 illustrates another example of the subject matter described herein. [Figure 4] FIG. 1 illustrates another example of the subject matter described herein. [Figure 5] FIG. 1 illustrates another example of the subject matter described herein. [Figure 6] FIG. 1 illustrates another example of the subject matter described herein. [Figure 7] FIG. 1 illustrates another example of the subject matter described herein. [Figure 8] FIG. 1 illustrates another example of the subject matter described herein. [Figure 9] FIG. 1 illustrates another example of the subject matter described herein. DETAILED DESCRIPTION OF THE INVENTION

[0068] The figures are not necessarily to scale. Certain features and views of the figures may be shown diagrammatically or exaggerated in scale for clarity and conciseness. For example, the dimensions of some elements in the figures may be exaggerated relative to other elements to aid in illustration. Like reference numerals may be used in the figures to designate like features. For clarity, not all reference numerals may appear in every figure.

[0069] In the drawings (and descriptions), similar features may be referenced by the same three-digit number. In the drawings (and descriptions), an optional subscript to the three-digit number may be used to distinguish between different instances of similar features. Thus, a three-digit number without a subscript may be used as a general reference, and a three-digit number with a subscript may be used as a specific reference. A subscript may include one digit that labels a different instance. A subscript may include two digits, with a first digit that labels a group of instances and a second digit that labels a different instance of the group.

[0070] Saving words / definition 5G (5th Generation) CE Control Elements CU Central Unit / Central Node CSI Channel State Information DL Downlink DU Distributed Unit / Distributed Node gNB gNodeB HO Handover ID Identifier L1 Layer 1 L2 Layer 2 L3 Layer 3 MAC Media Access Control NR New Radio RAN Radio Access Network RRC Radio Resource Configuration UCI Uplink Control Information UE User Equipment UL Uplink

[0071] 1 illustrates a schematic diagram of an embodiment of a network 100 comprising multiple network nodes, including terminal nodes 110 (also referred to as user equipment, UE), access nodes 120, and one or more core nodes 130. The terminal nodes 110 and access nodes 120 communicate with each other. The access nodes 120 communicate with one or more core nodes 130. One or more core nodes 130 may communicate with each other in some, but not necessarily all, embodiments. One or more access nodes 120 may communicate with each other in some, but not necessarily all, embodiments.

[0072] Network 100, in this example, is a wireless telecommunications network, or radio access network, RAN, in which at least some of the end nodes 110 and access nodes 120 communicate with each other using the transmission / reception of radio waves.

[0073] The RAN 100 may be a cellular network comprising multiple cells 122, each served by an access node 120. The access nodes 120 comprise cellular radio transceivers. The end nodes 110 comprise cellular radio transceivers.

[0074] In the particular embodiment shown, network 100 is a Next Generation (NG) or New Radio (NR) network, where NR is the third generation Partnership Project (3GPP) name for fifth generation (5G) technology.

[0075] The interface between the end node 110 and the access node 120 is a radio interface 124 (e.g., a Uu interface). The interface between the access node 120 and one or more core nodes 130 is a backhaul interface 128 (e.g., an S1 and / or NG interface).

[0076] Depending on the exact deployment scenario, the access nodes 120 can be RAN nodes, such as NG-RAN nodes. The NG-RAN nodes may be g NodeBs (gNBs) that provide NR user plane and control plane protocol terminations toward the UE. The NG-RAN nodes may also be Evolved Universal Terrestrial Radio Access network (E-UTRAN) NodeBs (ng-eNBs) that provide E-UTRA user plane and control plane protocol terminations toward the UE. The gNBs and ng-eNBs may be interconnected with each other by an Xn interface. The gNBs and ng-eNBs are similarly connected to the 5G Core (5GC) by an NG interface, more specifically to the Access and Mobility management Function (AMF) by an NG-C interface, and to the User Plane Function (UPF) by an NG-U interface. The access nodes 120 may be interconnected with each other by an Xn interface 126. The cellular network 100 may be configured to operate in licensed or unlicensed frequency bands, particularly, for example, the 60 GHz unlicensed band, where beamforming is enforced to achieve the required coverage.

[0077] The access node 120 may be deployed in an NR standalone operation / scenario. The access node 120 may be deployed in an NR non-standalone operation / scenario. The access node 120 may be deployed in a Carrier Aggregation (CA) operation / scenario. The access node 120 may be deployed in a dual connectivity operation / scenario, i.e., in particular, for example: Evolved Universal Terrestrial Radio Access - New Radio Dual Connectivity (EUTRA-NR-DC, also known as EN-DC), New Radio-Evolved Universal Terrestrial Radio Access Dual Connectivity (NR-EUTRA-DC, also known as NE-DC), Next Generation Radio Access Network Evolved Universal Terrestrial Radio Access-New Radio Dual Connectivity (NG-RAN E-UTRA-NR Dual Connectivity, also known as NGEN-DC), or New Radio Dual Connectivity (also known as NR-DC) It can be deployed with Multi-Radio Access Technology-Dual Connection (MR-DC) such as:

[0078] In such a non-standalone / dual connectivity deployment, the access nodes 120 may be interconnected to each other by X2 or Xn interfaces and connected to the Evolved Packet Core (EPC) by an S1 interface or to the 5GC by an NG interface.

[0079] A terminal node 110 is a network element in a network that terminates the user side of a wireless link. A terminal node 110 is a device that enables access to network services. A terminal node 110 may also be referred to as a user equipment (UE), a mobile terminal, or a mobile station. The term "user equipment" may be used to designate a mobile device that includes a smart card for authentication / encryption, such as a subscriber identity module (SIM). In other embodiments, the term "user equipment" may be used to designate a mobile device that includes circuitry embedded as part of the user equipment for authentication / encryption, such as a software SIM.

[0080] The access node 120 is a network element in the network responsible for radio transmission and reception in one or more cells 122 to or from the end nodes 110. Such an access node may also be called a transmission reception point (TRP) or base station. The access node 120 is the network termination of a radio link. The access node 120 may be implemented as a single network device or may be disaggregated / distributed across two or more RAN nodes, such as a central unit (CU), a distributed unit (DU), or a remote radio head-end (RRH), using different functional division architectures and different interfaces.

[0081] In the following description, the access node will be referred to as gNB7120 and the terminal node 110 will be referred to as UE110.

[0082] 2 shows an embodiment of an access node 120 (e.g., a gNB). In this embodiment, the access node has a split architecture. The gNB 120 has one or more distributed units / distributed nodes (gNB-DU) 220 and a central unit / central node (gNB-CU) 210.

[0083] The gNB-CU 210 is a logical node, called a central node, configured to host the radio resource connection (RRC) layer and other layers of the gNB 120. The gNB-CU 210 controls the operation of one or more gNB-DUs 220. The gNB-DUs 220 are logical nodes, called distributed nodes, configured to host the radio link control (RLC) protocol layer, medium access control (MAC) layer, and physical (PHY) layer of the access node (gNB) 120. The gNB-DUs 220 communicate with the RRC layer hosted by the gNB-CU via a dedicated interface 250 (F1).

[0084] One gNB-DU 220 can support one or more cells 122 (not shown). One cell is supported by only one gNB-DU 220.

[0085] The gNB-CU 210 and gNB-DU 220 communicate over a dedicated interface 250, the F1 interface. The F1 interface 250 connects the radio resource connectivity (RRC) layer hosted by the gNB-CU 210 to different lower layers (e.g., Layer 1 and Layer 2) hosted by the gNB-DU 220. The F1 interface functions are divided into F1 control plane functions (F1-C) 2501 and F1 user plane functions (F1-U) 2502.

[0086] In the following description, the central unit of the gNB (i.e., gNB-CU) will be referred to as CU210, the distributed unit of the gNB (i.e., gNB-DU) will be referred to as DU220, and the terminal node 110 will be referred to as UE110.

[0087] As discussed above, the gNB comprises a node that provides NR user plane and control plane protocol terminations towards the UE. The gNB is connected to the 5GC by an NG interface, for example, in accordance with 3GPP TS 38.300 V16.6.0(2021-06) Section 3.2.

[0088] The CU comprises a logical node that hosts, for example, the RRC, SDAP, and PDCP protocols of a gNB or the RRC and PDCP protocols of an en-gNB, controlling the operation of one or more DUs. The CU terminates the F1 interface connected to the DU.

[0089] The DU comprises, for example, a logical node that hosts the RLC, MAC, and PHY layers of a gNB or en-gNB, and its operation is partially controlled by the CU. One DU supports one or more cells. One cell is supported by only one DU. The DU terminates the F1 interface that is connected to the CU.

[0090] The CU-Control Plane (i.e., CU-CP) comprises, for example, a logical node that hosts the control plane portion of the RRC and PDCP protocols of the CU for, for example, an en-gNB or a gNB. The CU-CP terminates the E1 interface connected to the CU-UP and the F1-C interface connected to the DU.

[0091] The CU-User Plane (i.e., CU-UP) comprises, for example, a logical node that hosts, for example, the user plane portion of the PDCP protocol of the gNB-CU for the en-gNB and the user plane portion of the PDCP protocol and SDAP protocol of the gNB-CU for the gNB. The gNB-CU-UP terminates the E1 interface connected to the gNB-CU-CP and the F1-U interface connected to the gNB-DU, for example, in accordance with 3GPP TS 38.401 V16.6.0(2021-07) Section 3.1.

[0092] Different divisions of functionality between CU and DU are possible, e.g., called options: Option 1 (1A-like split): The functional split in this option is similar to the 1A architecture in the DC. The RRC is in the CU. The PDCP, RLC, MAC, physical layer, and RF are in the DU. Option 2 (3C-like split): The functional split in this option is similar to the 3C architecture in the DC. RRC and PDCP are in the CU. RLC, MAC, physical layer, and RF are in the DU. Option 3 (intra-RLC split): Low RLC (partial functions of RLC), MAC, physical layer, and RF are in the DU. PDCP and high RLC (other partial functions of RLC) are in the CU. Option 4 (RLC-MAC Split): MAC, physical layer, and RF are in the DU. PDCP and RLC are in the CU. Otherwise, follow, for example, 3GPP TR 38.801 V14.0.0(2017-03) Section 11.

[0093] The gNB supports different protocol layers, for example, Layer 1 (L1) to the physical layer.

[0094] Layer 2 (L2) of NR consists of the following sublayers: Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Service Data Adaptation Protocol (SDAP). where, for example: The physical layer provides transport channels to the MAC sublayer, The MAC sublayer provides logical channels to the RLC sublayer. The RLC sublayer provides an RLC channel to the PDCP sublayer; The PDCP sublayer provides radio bearers to the SDAP sublayer. The SDAP sublayer provides QoS flows for 5GC. Comp. refers to header compression, Segm. refers to segmentation, The control channels include (BCCH, PCCH).

[0095] Layer 3 (L3) includes, for example, Radio Resource Control (RRC), for example, according to 3GPP TS 38.300 V16.6.0(2021-06) Section 6.

[0096] A RAN (Radio Access Network) node or network node or central node or distributed node (e.g., gNB, base station, CU or DU, or a predetermined part thereof) may be implemented using, for example, a device having at least one processor and / or at least one memory (having computer readable instructions (computer programs)) configured to support and / or provide and / or process CU and / or DU related functions and / or features and / or at least one protocol (sub)layer of the RAN (Radio Access Network), for example, Layer 2 and / or Layer 3. They may be executed using specific means configured to perform each specific task, for example, Layer 3 means for performing Layer 3 operations, Layer 2 means for performing Layer 2 operations, etc.

[0097] The CU and DU portions may be, for example, co-located or physically separated. The gNB DU may be further divided into, for example, two portions, e.g., a portion including processing equipment and a portion including antennas. The CU may be referred to as a BBU / REC / RCC / C-RAN / V-RAN, O-RAN, or a predetermined portion thereof. The DU may be referred to as an RRH / RRU / RE / RU, or a predetermined portion thereof.

[0098] A DU may support one or more cells and thus serve, for example, as a serving cell for a user equipment (UE).

[0099] A user equipment (UE) may include a wireless or mobile device, a device having a radio interface that interacts with a RAN (Radio Access Network), a smartphone, an in-vehicle device, an IoT device, an M2M device, or others. Such a UE or device may include: at least one processor and at least one memory including computer program code configured to cause the device, using the at least one processor, to perform at least certain operations, such as, for example, an RRC connection to the RAN. The UE may be configured, for example, to generate a message (e.g., including a cell ID) to be transmitted over the air toward the RAN (to reach and communicate with a serving cell). The UE may generate, send, and receive RRC messages including one or more RRC PDUs (Packet Data Units).

[0100] The UE may have different states (e.g., according to 3GPP TS 38.331 V16.5.0(2021-06) sections 42.1 and 4.4).

[0101] When an RRC connection is established, the UE is, for example, in an RRC_CONNECTED state or an RRC_INACTIVE state.

[0102] In RRC_CONNECTED state the UE: may store AS context, may forward unicast data to / from the UE, may monitor a control channel associated with the shared data channel to determine whether data is scheduled for the data channel; may provide channel quality and feedback information; and / or Neighbor cell measurements and measurement reporting may be performed.

[0103] The RRC protocol includes, for example, the following main mechanisms: RRC connection control, Measurement configuration and reporting, Establishing / modifying / releasing measurement configurations (e.g., intra-frequency, inter-frequency, and inter-RAT measurements); Setting up and releasing the measurement gap, and / or Measurement Reporting Includes.

[0104] FIG. 3 shows an example of message exchange for L1 / L2 based inter-cell mobility (L1 / 2 centric mobility, L1 / 2 inter-cell mobility, and Lower Layer Mobility, LLM).

[0105] In L1 / L2-based inter-cell mobility, the handover decision (e.g., regarding a cell change, such as changing the UE 110 from a serving cell served by a serving DU "Source DU" 2201 to a target cell) is made by source-DU-based L1 measurements (e.g., received from the UE), and the command to perform the handover is made by L2 signaling (e.g., MAC CE triggering the handover) from the source DU to the UE (the UE is pre-configured for handover to the target cell but is configured to wait for the source DU's command / trigger to complete the handover). In this regard, inter-cell mobility is based on L1 measurements and triggered by L2 signaling (hence, such mobility is referred to as "L1 / L2"-based inter-cell mobility).

[0106] In the handover scenario shown in the message exchange of Figure 3, the handover is to the target cell of the target DU 2202. However, it is recognized that in other scenarios, the target cell may be the cell of the source DU itself 2201 (whereby the target DU is, in effect, the source DU).

[0107] In this scenario, the UE 110 has established a connection to the RAN and is initially served by a source DU 2201.

[0108] In block 1, the UE 110 provides the source DU 2201 with L3 measurements of the target DU, for example, measurements of one or more beams of one or more target cells of the target DU.

[0109] In block 2, the L3 measurements are transferred by the target DU to the CU-CP 230 via UpLink, UL, and RRC message transfer.

[0110] In block 3, the CU-CP performs handover, HO, decisions based on L3 measurements and makes decisions regarding cell preparation.

[0111] In block 4, the CU-CP proceeds to set up the context in the target DU via a UE Context Setup Request message.

[0112] In block 5, the target DU responds by sending a UE Context Setup Response message to the CU-CP.

[0113] As part of handover preparation, the source DU may be configured to receive UE L1 measurements for the target DU's newly prepared target cell. In that regard, the source DU may receive a UE context modification request from the CU, which includes configuration information for requesting / enabling the source DU to modify the source DU's lower layer configuration, e.g., at least some of its Layer 1 and / or Layer 2 configurations / protocols. The UE context modification request may be used to encapsulate an RRC message that the source DU subsequently sends to the UE (the source DU may send an RRC reconfiguration toward the UE after receiving the RRC reconfiguration in the UE context modification request from the CU). The sending of the UE context modification request from the CU to the source DU and the source DU's response thereto to the CU are not shown in FIG. 3 (but are shown and discussed below with respect to blocks 5 and 6 of FIG. 4).

[0114] In block 6, the CU-CP communicates with the CU-UP 240 to perform bearer context setup by sending a bearer context setup request message.

[0115] In block 7, the CU-UP responds with a bearer context setup response message.

[0116] In block 8, the CU-UP sends an RRC reconfiguration message to the source DU using DownLink, UL, RRC message transport.

[0117] In some embodiments of L1 / L2 based inter-cell mobility, the RRC reconfiguration message may actually include two UE configuration components, a first and a second configuration component.

[0118] The first configuration component of the RRC reconfiguration message may include configuration information to enable the UE to reconfigure its lower layer configuration, e.g., to reconfigure its L1 configuration, such as to change the configuration of the UE's L1 measurement reports. For example, the UE may be configured to change its L1 measurement reports from reporting measurements of the beams of the current serving cell to reporting measurements of both beams: some beams of the current serving cell and some beams of the target cell (such measurements of the beams of the target cell in the L1 measurement reports will thereby be used by the source DU to decide if / when to trigger the UE to change cells to the target cell). In L1 / L2-based inter-cell mobility, the first configuration component is applied immediately by the UE, i.e., immediately following receipt of the RRC reconfiguration message.

[0119] As an example, the lower layer configuration could be, for example, a reconfiguration of the UE's L1 measurements and L1 beam reports, so that instead of associating SSB indices 0 to L-1 (where L=number of cell beams, e.g., 6) with beam measurements for beams 1 to L of the serving cell, SSB indices 0 to X-1 may be associated with X beams of the serving cell, and The SSB indices 0 to X to L1 may be associated with Y beams of the target cell.

[0120] In some embodiments, there may be more than one target cell (and / or more than one target DU for each of the more than one target cells). a) There is a possibility to associate 0 to 1 with the beam measurements for the two beams of the serving cell; b) 2 to 3 may be associated with beam measurements for two beams of the first target cell of the first target DU; c) Possibility of relating 4 to 5 to beam measurements for two beams of the second target cell of the second target DU.

[0121] The second configuration component of the RRC reconfiguration message may contain configuration information for the UE to switch from the currently serving source cell to the target cell, where application of the configuration information is delayed until triggered by a command from the DU. In L1 / L2-based inter-cell mobility, the second configuration component is not applied immediately by the UE upon receiving the RRC reconfiguration message, but instead is applied only when subsequently triggered to do so by the source DU (i.e., by L2 signaling / MAC CE in block 13). When appropriately triggered, the UE applies the second configuration component and proceeds to perform a random access procedure to the target cell (blocks 15-17).

[0122] In block 9, the source DU forwards an RRC reconfiguration message to the UE.

[0123] In block 10, the UE applies the first configuration component and modifies its lower layer configuration appropriately, and responds to the RRC reconfiguration message with a reconfiguration complete message that is forwarded to the CU-CP in block 11.

[0124] In block 12, the UE sends periodic L1 reports to the source DU, for example based on the configuration provided in block 9 (i.e., lower layer configuration changes), so that the UE's L1 beam measurement report includes measurements of one or more beams of the target cell of the target DU.

[0125] If the source DU determines, based on the received L1 measurement report (i.e., L1 signaling), that the UE should be handed over to another cell (i.e., the target cell of the target DU), the source DU triggers L1 / L2-based inter-cell mobility by sending a MAC CE (i.e., L2 signaling) to the UE in block 13. By this point, the UE has received data from the serving DU, as shown in block 14.

[0126] In response to the MAC CE, the UE applies the RRC configuration for the target cell (i.e., the target DU) indicated by the MAC CE and performs a Random Access (RA) procedure to the target DU, as indicated by blocks 15 and 16.

[0127] In block 17, after the RA procedure, the UE sends an RRC reconfiguration complete message to the target DU, and the RRC reconfiguration complete message is forwarded to the CU-CP by UL RRC message forwarding in block 18.

[0128] In blocks 19 and 20, the CU-CP performs a bearer modification with the CU-UP to update the bearer setup and for the CU-UP to start forwarding data to the target DU (and stop forwarding data to the source DU). This is done by a Modify Bearer Context Request message from the CU-CP to the CU-UP in block 19 and a Modify Bearer Context Response message from the CU-UP to the CU-CP in block 20. Once this is complete, the UE starts receiving data from the target DU, as shown in block 21.

[0129] In block 22, the CU-CP releases the UE context from the source DU with a UE context release request message, and the source DU responds to the UE context release request message with a UE context release complete message.

[0130] In some embodiments, L1 / L2-based inter-cell mobility (ie, its mechanisms and procedures) may provide a way to reduce latency, overhead, and (service) interruption time in inter-cell mobility.

[0131] In some embodiments, L1 / L2 based inter-cell mobility includes: Configuration and maintenance for multiple candidate target cells to enable fast application of configurations for candidate target cells; Dynamic switch mechanisms between candidate serving cells (including special cells, SpCells and secondary cells, SCells) for possible applicable scenarios based on L1 / L2 signaling; L1 enhancements for inter-cell beam management, including L1 measurement and reporting and beam direction; Timing advance management, and CU-DU interface signaling to support L1 / L2-based inter-cell mobility may be provided.

[0132] The L1 / L2 based inter-cell mobility procedure is applicable to the following scenarios: Standalone, CA, and NR-DC cases with serving cell change within one carrier group, CG Intra-DU cases, intra-CU cases, and inter-DU cases (applicable for standalone and CA) Both same-frequency and different-frequency Both FR1 and FR2 The source and target cells may or may not be synchronized may be applicable to

[0133] Figure 4 shows a further example of message exchange (roughly similar to that of Figure 3) for L1 / L2 based inter-cell mobility, where the serving / source DU makes the handover decision for cell change based on L1 signaling (i.e. L1 measurement reports) and the source DU triggers the cell change by L2 signaling (i.e. MAC CE).

[0134] In blocks 1-4, the CU 210 determines the readiness of the target cell controlled by the target DU 2202 for lower layer mobility based on measurement reports from the UE forwarded to the CU by the source DU 2201. Blocks 1, 2, 3, and 4 roughly correspond to blocks 1, 2, 4, and 5 in FIG.

[0135] As part of the preparation, the source DU is configured to receive UE L1 measurements for the target DU's newly prepared cell in blocks 5-6 (equivalent blocks are not shown in Figure 3, but may be present). Therefor, the source DU receives a UE context modification request from the CU, which includes configuration information for requesting / enabling the source DU to change at least some of its lower layer configuration.

[0136] Block 7 roughly corresponds to block 8 in FIG.

[0137] In block 8, the UE sends an L1 measurement report, the configuration of which follows the lower layer configuration received in the last RRC reconfiguration that the UE previously received from the network / CU (i.e., prior to receiving the new RRC reconfiguration in block 9).

[0138] In block 9, the UE receives a new RRC reconfiguration from the network / CU instructing the target DU to prepare a new target cell for L1 / L2-based inter-cell mobility. The RRC reconfiguration also requests the UE to change at least some of its lower layer configurations, e.g., configure the UE to report at least some L1 measurements for the newly configured target cell.

[0139] In block 10, the UE sends an RRC reconfiguration complete message to the DU, which forwards the RRC reconfiguration complete message to the CU in block 11.

[0140] In block 12, the CU sends an RRC reconfiguration complete indicator to the DU.

[0141] Meanwhile, in block 13, the UE starts sending L1 measurement reports using the new RRC reconfiguration received from the network / CU in block 9.

[0142] A problem with conventional L1 / L2-based inter-cell mobility is that the source DU does not know exactly when the UE applies the new RRC reconfiguration in block 9, i.e., the source DU does not know when the UE changed its lower layer configuration according to the RRC reconfiguration message in block 9. (It is noted that the RRC messaging is effectively “transparent” to the source DU, i.e., the source DU does not know the content of the RRC messages and therefore does not know that the UE applied the reconfiguration according to the UE's RRC reconfiguration complete message in block 10.) Therefore, the source DU cannot determine whether the received L1 measurement report in block 13 follows the new RRC reconfiguration in block 9 or the previous RRC reconfiguration. Therefore, the source DU may misinterpret the UE's L1 measurement report in block 13 of FIG. 4, i.e., misinterpret the radio measurements and SSB resource indicators included in the L1 measurement report in block 13. Since the source DU makes handover decisions based on the L1 measurement report, misinterpretation of the L1 measurement report may lead to the source DU making incorrect or suboptimal handover decisions.

[0143] It may be possible to perform a "with sync" reconfiguration in blocks 9-10, but this requires the use of random access to the serving DU and dormancy of the PCDP and RLC layers. Performing random access and resetting protocol layers after each RRC reconfiguration would lead to delays and disruption times that would defeat the purpose of L1 / L2-based inter-cell mobility.

[0144] Various embodiments of the present disclosure attempt to address such issues in L1 / L2 based inter-cell mobility.

[0145] Certain embodiments of the present disclosure provide methods for ensuring synchronization of the applied L1 / L2 configuration in the UE (e.g., following the RRC reconfiguration message of block 9 of FIG. 4) and the L1 / L2 configuration in the DU (e.g., following the UE context modification request message of block 5 of FIG. 4).

[0146] In various embodiments of the present disclosure, when a CU requests a UE context modification that includes a change to a lower layer configuration, the UE context modification request sent by the CU in this regard is identified by an identifier, ID, which is included in the UE context modification request. In this regard, the CU generates an ID that identifies the request and communicates the ID to the source DU and the UE.

[0147] The DU may send a UE context modification request including the ID to the CU, and the CU may send an RRC reconfiguration message to the UE (via the DU), which includes the ID generated by the CU (and also communicated to the source DU).

[0148] This RRC reconfiguration may include an indicator requesting the UE to confirm to the DU that it has performed the requested lower layer configuration changes. In this regard, such an indicator may be a flag meaning "L1-sync is needed" and an ID sent by the UE, for example, via L1 signaling. The inclusion of the ID in the RRC configuration may be implicitly considered as triggering the activation for L1 synchronization. In other words, the presence of the ID itself in the RRC configuration may serve as an indicator.

[0149] In an embodiment of the present disclosure, in response to the UE applying the new RRC reconfiguration and completing the reconfiguration of its lower layer protocols, the UE sends out L2 or L1 signaling (e.g., L1 signal such as MAC CE or L1 measurement report) including the received ID to notify the DU that the UE has applied the new lower layer configuration.

[0150] In some embodiments, the ID can be a flag or a single-bit identifier signaled over the existing L1 uplink control channel indication (instead of a multi-bit / long identifier ID). This method can be used when the CU only prepares a single target DU configuration for L1 / L2-based inter-cell mobility operation, ensuring that no other reconfiguration is applied after the L1 / L2-based inter-cell mobility configuration.

[0151] In some embodiments, the ID may be included by the UE in an L1 measurement report (e.g., channel state information, CSI, report) after applying a new RRC reconfiguration. The L1 indication may be included always (e.g., in each L1 measurement report) or only once after the UE applies a new RRC reconfiguration.

[0152] Similar to the baseline / traditional L1 / L2-based inter-cell mobility operation (shown in FIG. 3), in an embodiment of the present disclosure, after successfully applying the lower layer configuration using the new RRC configuration, the UE may also send an RRC reconfiguration complete message to the source DU, and the source DU forwards the RRC reconfiguration complete message to the CU.

[0153] FIG. 5 shows a signaling diagram illustrating the exchange of signals / messages (between the UE 110 and the source gNB-DU "DU" 220 and gNB-CU "CU" 210) for use in L1 / L2-based inter-cell mobility in accordance with an embodiment of the present disclosure.

[0154] One or more of the features discussed in connection with Figure 5 may be found in one or more of the other figures, and during the discussion of Figure 5, reference will be made to the other figures for explanation.

[0155] In the embodiment of FIG. 5, the UE is configured to access a RAN, which includes at least a CU (which may be referred to herein as a "central node") and DUs (which may be referred to herein as "distributed nodes") that serve the UE, and the central node controls the distributed nodes.

[0156] The UE comprises means (e.g., at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the UE to perform at least establishing the connection) configured to establish a connection towards a radio access network, as shown in block 501.

[0157] The UE is further configured to receive a UE context modification request from the central node, as shown in block 502. The UE context modification request includes: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request (e.g., an identifier that identifies the request, which may be generated by the CU and pre-assigned / associated with the request) Includes.

[0158] Block 502 is somewhat similar to blocks 8 and 9 of FIG. 3 and blocks 7 and 10 of FIG. 4, although the UE context modification request of block 502 further includes an identifier.

[0159] The UE is further configured to implement the requested change in lower layer configuration, as indicated by block 503 .

[0160] Based at least in part on implementing the requested lower layer configuration change (e.g., in response to applying / completing the requested lower layer configuration change), the UE: Sending a confirmation that the requested changes have been implemented towards the central node (thereby informing the CU that the requested lower layer configuration has been implemented / completed - block 504 is somewhat similar to blocks 10 and 11 of Figure 3 and blocks 10 and 11 of Figure 4), as shown in block 504; and 5. Transmit the identifier towards the distributed node, as shown in block 505 (which the DU may use to determine that the requested lower layer configuration has been implemented / completed, as discussed with respect to FIG. 6 ). It is configured as follows.

[0161] In some embodiments, the UE context modification request includes: Layer 3 protocol messages, Radio resource configuration, RRC,messages, and, RRC Reconfiguration Message and is received from the central node.

[0162] In some embodiments, the identifier is: Through Layer 2 signaling, In Layer 2 protocol messages, and Medium Access Control, MAC, Control Element, CE , which is one selected from the group of , and is sent towards the distributed node.

[0163] In some embodiments, the identifier is: Through Layer 1 signaling, Uplink Control Information, UCI, In the channel state information, CSI, report, and Layer 1 measurement report , which is one selected from the group of , and is sent towards the distributed node.

[0164] In some embodiments, the identifier is: Through Layer 1 signaling, Uplink control information, UCI (e.g., Physical Uplink Control Channel (PUCCH)), sent via Sent via an uplink control channel such as PUCCH), In the channel state information, CSI, report, and Layer 1 Measurement Report (Layer 1 Beam Measurement Report) one or more Layer 1 measurement reports, one selected from the group and is sent to the distributed node.

[0165] In some embodiments, the UE context modification request includes an indicator for the UE to request the UE to confirm to the distributed node that the UE has implemented the requested changes, and the UE is further configured to, based at least in part on the received indicator, send an indicator to the distributed node for confirming to the distributed node that the UE has implemented the requested changes.

[0166] In some embodiments, the indicator is a flag or an identifier (ie, the identifier itself serves as the indicator).

[0167] In some embodiments, the identifier is: an identifier to identify the request (e.g., an identifier generated by the CU associated with / assigned to the request); a multi-bit identifier, or Flags is.

[0168] In some embodiments, the UE context modification request is a request for use in a handover procedure for handing over the UE from a currently serving cell to another cell (controlled or not controlled by the DU). In some embodiments, the UE context modification request is a request for use in an L1 / L2 based inter-cell mobility procedure for switching the UE between cells.

[0169] In some embodiments, the requested change in the lower layer configuration is: Reconfiguring a lower layer protocol of the UE; Coordinating Layer 1, L1, measurements performed by the UE; and Reconstructing a L1 measurement report of the UE; measuring one or more beams of the target cell; reporting one or more measurements of one or more beams of the target cell; The request includes a request made by the UE to at least one selected from the group consisting of:

[0170] FIG. 6 shows a signaling diagram illustrating the exchange of signals / messages (between the UE 110 and the source gNB-DU "DU" 220 and the gNB-CU "CU" 210) for use in L1 / L2-based inter-cell mobility according to a further embodiment of the present disclosure.

[0171] One or more of the features discussed in connection with Figure 6 may be found in one or more of the other figures, and during the discussion of Figure 6, reference will be made to the other figures for explanation.

[0172] At block 601, the CU generates an identifier, ID, associated with a request to modify at least a portion of a lower layer configuration. For example, the ID is configured to identify the request, and the CU assigns / associates the ID with the request.

[0173] At block 602, the CU sends a first UE context modification request to the distributed node. The first UE context modification request includes: A request to change at least part of the lower layers (i.e., for the DU to change its lower layer configuration), and identifier Includes.

[0174] Block 602 is somewhat similar to block 5 of Figure 4, although the first UE context modification request of block 602 further includes an identifier. In response to receiving the UE context modification, the DU may send a response to the CU (similar to block 6 of Figure 4 (according to block 2 of Figure 7) although the response may further include an identifier), and the DU may apply the requested changes to its lower layer configuration.

[0175] In some embodiments, the first UE context modification request comprises: Reconfiguring a lower layer protocol of the UE; Coordinating interpretation of Layer 1, L1, measurement reports received from the UE; receiving L1 measurements from the UE for the target cell; Associating one or more measurements from a measurement report received from the UE with one or more beams of the target cell; UE, target cells controlled by the DU, a target cell controlled by another DU, and One or more candidate target cells and handing over to at least one selected from the group The request includes a request to perform at least one or more of the following:

[0176] In some embodiments, the first UE context modification request includes a plurality of requested changes to one or more lower layer configurations; the identifier is configured to distinguish between multiple requested modifications; or The identifiers include a plurality of identifiers configured to identify a plurality of requested modifications, respectively.

[0177] In some embodiments, the distributed node: and / or adjusting the interpretation of Layer 1, L1, measurement reports received from the UE based at least in part on the identifier received from the central node; Associating one or more measurements from a measurement report received from the UE with one or more beams of the target cell based at least in part on the identifier received from the central node. It is configured as follows.

[0178] In response to completing the requested lower layer configuration change, the DU may send a confirmation to the CU that the requested change has been implemented (not shown). The response to the first UE context modification request may include an identifier to identify the request or a replacement identifier (e.g., if the DU was already using the originally proposed identifier generated by and received from the CU). Such a replacement identifier may be used in subsequent blocks instead of the identifier generated by the CU.

[0179] In block 502, the CU sends a second UE context modification request to the UE, the second UE context modification request including: a request to change at least a part of the lower layer configuration (i.e., for the UE to change its lower layer configuration); and identifier Includes.

[0180] Blocks 503 to 505 are the same as blocks 503 to 505 in FIG.

[0181] In block 603, the DU determines whether the UE has implemented the requested change based at least in part on the identifier received from the UE in block 505. In this regard, because the UE only sends the identifier in response to completing the requested change, the DU can determine that the requested lower layer configuration is complete based on matching the identifier received from the UE in block 505 with the identifier received from the CU in block 602.

[0182] In block 604 , the UE sends an L1 measurement report according to the lower layer reconfiguration received in block 502 .

[0183] Following the determination of block 605, the DU may determine that the L1 measurement report is in accordance with the lower layer reconfiguration received in block 502. In this regard, the lower layer reconfiguration received in block 502 may be Coordinating Layer 1, L1, measurements performed by the UE; and Reconstructing a L1 measurement report of the UE; measuring one or more beams of a target cell (or one or more candidate target cells); reporting one or more measurements of one or more beams of the target cell (or one or more candidate target cells); The request may be made by the UE to perform one or more of the following:

[0184] Therefore, the DU must ensure that the L1 measurements received from the UE are target cell, one or more candidate target cells; one or more beams of the target cell; and One or more beams of one or more candidate target cells It can be determined whether the information is associated with at least one selected from the group:

[0185] DU is an identifier received from the UE; and an L1 measurement report received from the UE following receipt of an identifier from the UE; The method may be configured to determine to trigger the UE to perform a handover of the UE to the target cell based at least in part on at least one selected from the group of:

[0186] In block 605, the DU determines whether to change / switch the UE's serving cell to the target cell. This determination is based at least in part on the received identifier in block 505 and the subsequently received L1 measurement report in block 604.

[0187] Because the DU can determine, based at least in part on the identifier received from the UE in block 505, that the UE has implemented the requested changes, the DU can verify that the L1 measurement report received in block 604 complies with the lower layer reconfiguration of the most recent UE context modification request (i.e., the L1 measurement report complies with an earlier / earlier received lower layer configuration received before the UE context modification request in block 502). Advantageously, the DU thereby knows that both it (following block 602) and the UE (following block 502) have applied lower layer reconfiguration, and thus the DU's lower layer reconfiguration is "in-sync" with the UE's lower layer reconfiguration. Advantageously, this can avoid / reduce the risk of the DU misinterpreting the L1 measurement report in block 604. Furthermore, because the DU makes handover decisions that determine a cell change / switch based on the L1 measurement report, this can avoid / reduce the DU making incorrect or suboptimal handover decisions.

[0188] In block 606, following the DU's decision in block 605 to change the UE's serving cell to the target cell, the DU triggers the UE to perform a handover of the UE to the target cell.

[0189] FIG. 7 illustrates a message flow (between the UE 110 and the source gNB-DU “DU” 220 and the gNB-CU “CU” 210) for use in L1 / L2-based inter-cell mobility in accordance with an embodiment of the present disclosure.

[0190] In block 1, the CU requests modification of the UE context, including lower layers (e.g., Layer 1 reconfiguration request), by sending a UE context modification request to the DU. The request is identified by an ID. The DU stores the UE's previous Layer 1 configuration until the UE indicates that it has switched to a new L1 configuration (i.e., in block 5, discussed below).

[0191] In block 2, in response to the UE context modification request received from the CU, the DU sends a UE context modification request to the CU. An ID may be included in this message. Similarly, if the DU determines that the ID received from the CU is already in use by the DU, the DU can generate its own replacement ID to identify the request, for example, in the UE context modification request of block 2, and send the replacement ID to the CU.

[0192] In block 3, the CU generates an RRC reconfiguration message including the ID and sends the RRC reconfiguration message to the UE via the DU via DL RRC message transfer.

[0193] In block 4, the RRC reconfiguration message is forwarded by the DU to the UE.

[0194] In block 5, once the UE has applied the requested reconfiguration, the UE sends a MAC CE indication to indicate that the UE has applied the changes requested in the message of block 4. The ID is included in the MAC CE.

[0195] Using the ID reported by the UE in block 5, the DU matches this ID with the ID it received from the CU in the context modification request in block 1, thereby determining that the UE has applied the requested lower layer reconfiguration and switched its L1 configuration.

[0196] As an alternative to sending the ID via Layer 2 signaling such as MAC CE in block 5, in other embodiments the ID may be sent by the UE in Uplink Control Information, UCI, which includes channel state information, CSI, reports (e.g., the ID may be included in an L1 beam measurement report - not shown), thereby conserving resources by reducing / saving MAC CE signaling.

[0197] In block 6, having applied the RRC reconfiguration, the UE responds to the CU by sending an RRC reconfiguration complete message to the CU via the DU.

[0198] In block 7, the DU transfers an RRC reconfiguration complete message to the CU via UL RRC message transfer.

[0199] In some embodiments, the ID / L1 indication can be a single bit signaled over the existing L1 uplink control channel (rather than the ID / L1 indication being a multi-bit / long identifier). This may be done if the CU only prepares a single target configuration for L1 / L2-based inter-cell mobility operation and the CU ensures / requires that no other reconfiguration is applied after the configuration for L1 / L2-based inter-cell mobility operation.

[0200] If the UE was not requested to send an L2 or L2 indication (i.e., was not requested via the messages of blocks 3 and 4 to send an L2 / MAC CE indication or an L1 indication in block 5), the ID may be omitted in the RRC reconfiguration message of blocks 3 and 4, and therefore no L2 or L1 indication will be sent in block 5.

[0201] Advantageously, the process of Figure 7 may avoid / reduce misinterpretation by the DU of L1 measurement reports subsequently received from the UE, so that the DU can properly determine (in accordance with blocks 604-606 of Figure 6) the correct / optimal lower layer mobility decision to trigger the UE to switch cells. The process of Figure 7 may ensure that the UE and DU are synchronized with the use of the new lower layer reconfiguration (i.e., reconfiguration for L1 / L2-based inter-cell mobility).

[0202] The signal diagrams of Figures 3-7 may be considered to illustrate multiple methods in the sense that they may be considered to illustrate one or more actions performed by / at multiple actors / entities (e.g., UE 110, DU 220, and CU 210). Accordingly, these diagrams may be considered to illustrate multiple individual methods performed by each respective actor / entity. These diagrams may also be considered to illustrate the transmission / communication / sending / receiving of various signals / messages / information (directly or indirectly) between actors / entities. Furthermore, for any transmitting / effecting transmitting feature / action shown in these diagrams, these diagrams may also be considered to illustrate the corresponding receiving / effecting receiving feature / action.

[0203] The various component blocks shown in the figures may be functional, and the functions described in each block may be implemented by a single physical entity (such as a UE, DU, and CU, and a suitably configured device as described with reference to FIG. 8). The functions described may also be performed by a computer program (as described with reference to FIG. 9). Thus, the blocks shown in the signal diagrams of FIGS. 3-7 may represent actions of a method, function, performed by an apparatus and / or by sections of instructions / code in a computer program.

[0204] The signal diagrams of Figures 3-7 each illustrate, among other things, possible scenarios. The order of the blocks shown is not necessarily required, and in principle certain of the blocks may be performed out of order (in particular, for example, blocks 504 and 505 of Figures 5 and 6 may be reversed).

[0205] It will be understood that each block and combination of blocks illustrated in Figures 3-7, as well as the additional functions described above, can be implemented by various means, such as hardware, firmware, and / or software, including one or more computer programs. For example, one or more of the functions described above can be implemented by a suitably configured device (such as a UE, DU, or CU comprising means for performing the functions described above). One or more of the functions described above can be embodied by a suitably configured computer program (such as a computer program including computer program instructions that, when executed by the device, cause the device to perform the functions described above). The computer program instructions can be stored in a memory storage device and executed by a processor.

[0206] As will be appreciated, any such computer program instructions can be loaded into a computer or other programmable device (i.e., hardware) to produce a machine where the instructions, when executed on the programmable device, create means for performing the functions specified in the blocks. These computer program instructions can also be stored on a computer-readable medium, and the computer program instructions can direct the programmable device to function in a particular manner, such that the instructions stored in a computer-readable memory produce an article of manufacture including instruction means for performing the functions specified in the blocks. The computer program instructions can also be loaded into a programmable device to cause a series of operational actions to be performed on the programmable device, thereby creating a computer-implemented process where the instructions executed on the programmable device provide actions for performing the functions specified in the blocks.

[0207] Although not all embodiments of the present disclosure may take the form of a method, apparatus, or computer program product, and thus, although not all embodiments of the present disclosure may be implemented in hardware, software, or a combination of hardware and software.

[0208] Although not all of the present disclosure is provided herein, various embodiments are described using flowchart illustrations and schematic block diagrams. It will be understood that each block (of the flowchart illustrations and block diagrams) and combinations of blocks can be implemented by computer program instructions of a computer program. These program instructions can be provided to one or more processors, processing circuitry, or controllers such that the instructions executing on the one or more processors, processing circuitry, or controllers create means for performing the functions specified in the one or more blocks, i.e., such that the method is computer-implemented. The computer program instructions, when executed by the processor, can cause a series of operational blocks / steps / actions to be performed by the processor, thereby creating a computer-implemented process in which the instructions executing on the processor provide steps for performing the functions specified in the one or more blocks.

[0209] Thus, the blocks support: a combination of means for performing the specified function, a combination of actions for performing the specified function, and computer program instructions / algorithms for performing the specified function. It will also be understood that each block and combination of blocks can be performed by a dedicated hardware-based system that performs the specified function or action or a combination of dedicated hardware and computer program instructions.

[0210] Various, but not necessarily all, embodiments of the present disclosure provide methods and corresponding apparatuses comprising various modules, means, or circuitry that provide functionality for performing / applying the actions of the methods. The modules, means, or circuitry may be implemented as hardware, or as software or firmware executed by a computer processor. In the case of firmware or software, embodiments of the present disclosure may be provided as a computer program product including a computer-readable storage structure having computer program instructions (i.e., software or firmware) embodied thereon for execution by a computer processor.

[0211] 8 illustrates a block diagram of an apparatus 10 for implementing the methods, processes, procedures, and signaling described in this disclosure, and particularly shown in FIGS. 5-7. In this regard, the apparatus may perform the role of the UE 110, the DU 220, or the CU 210 in the methods shown and described above. The component blocks of FIG. 2 are functional, and the described functions may be performed by a single physical entity.

[0212] The apparatus comprises a controller 11 which may be provided in a device such as a UE 110, a DU 220 or a CU 210.

[0213] The controller 11 may be embodied by a computing device, such as those specifically mentioned above. In some, but not necessarily all, embodiments of the present disclosure, the device may be embodied as a chip, chipset, circuitry, or module, i.e., for use in any of the above. As used herein, "module" refers to a unit or device that excludes specific parts / components that would be added by the end manufacturer or user.

[0214] The implementation of the controller 11 can be such as controller circuitry, the controller 11 can be implemented solely in hardware, can have certain aspects in software including firmware only, or can be a combination of hardware and software (including firmware).

[0215] The controller 11 may be implemented, for example, by using executable instructions of a computer program 14, which may be stored on a computer-readable storage medium 13, such as a disk or memory, in a general-purpose or special-purpose processor 12, using instructions that enable hardware functions to be performed by such processor 12.

[0216] Processor 12 is configured to read from and write to memory 13. Processor 12 may also comprise an output interface, via which data and / or commands are output by processor 12, and an input interface, via which data and / or commands are input to processor 12. The apparatus may be coupled to or comprise one or more other components 15 (e.g., wireless transceivers, sensors, input / output user interface elements, and / or other modules / devices / components for inputting and outputting data / commands, among others).

[0217] Memory 13 stores computer program 14, which includes computer program instructions (computer program code) that, when loaded into processor 12, control the operation of device 10. The computer program instructions of computer program 14 provide the logic and routines that enable the device to implement the methods, processes, and procedures described in this disclosure and particularly illustrated in Figures 5-7. Processor 12 can load and execute computer program 14 by reading memory 13.

[0218] The computer program instructions may be included in a computer program, a non-transitory computer-readable medium, a computer program product, a machine-readable medium, etc. In some, but not necessarily all, embodiments, the computer program instructions may be distributed across two or more computer programs.

[0219] Although memory 13 is shown as a single component / circuitry, it may be implemented as one or more separate components / circuitry, some or all of which may be integrated / removable and / or may provide permanent / semi-permanent / dynamic / cache storage.

[0220] Although processor 12 is shown as a single component / circuitry, it may be implemented as one or more separate components / circuitry, some or all of which may be integrated / removable. Processor 12 may be a single-core or multi-core processor.

[0221] An apparatus may include one or more components for performing the methods, processes, and procedures described in this disclosure and illustrated in the figures. It is contemplated that the functions of these components may be combined in one or more components or performed by other components of equivalent functionality. A description of a function should also be considered to disclose any suitable means for performing that function. Where a structural feature is described, the structural feature may be replaced by a means for performing one or more of the functions of the structural feature, whether that function or functions are explicitly or implicitly described.

[0222] While apparatus embodiments are described above in terms of including various components, it should be understood that the components may be embodied as or otherwise controlled by corresponding controllers or circuitry, such as one or more processing elements or processors of the apparatus. In this regard, each of the above-described components may be one or more of any device, means, or circuitry embodied in hardware, software, or a combination of hardware and software, configured to perform the corresponding function of each above-described component.

[0223] The device may be, for example, a UE 110, a DU 220, or a CU 210. In some embodiments, the device may be embodied as a chip, a chipset, a circuit unit, or a module, i.e., for use in any of the above.

[0224] In one example, the apparatus is a UE and may be embodied on a handheld portable electronic device such as a mobile phone, a mobile communication device, a wearable computing device, or a personal digital assistant, which may further provide one or more audio / text / video communication functions (e.g., telecommunications, video communication, and / or text transmission (Short Message Service (SMS), Multimedia Message Service (MMS) / email) functions), interactive / non-interactive viewing functions (e.g., web browsing, navigation, TV / program viewing functions), music recording / playback functions (e.g., Moving Picture Experts Group-1 Audio Layer 3 (MP3) or other formats and / or (frequency modulation / amplitude modulation) radio broadcast recording / playback), data downloading / playback functions, image capture functions (e.g., using a (e.g., built-in) digital camera), and gaming functions, or any combination thereof.

[0225] The UE may be provided within an electronic device, such as a mobile terminal. However, it should be understood that a mobile terminal is merely an example of an electronic device that would benefit from implementation embodiments of the present disclosure and, therefore, should not be considered to limit the scope of the present disclosure to the implementation embodiments. In certain implementation embodiments, the apparatus may be provided within a mobile terminal, although other types of electronic devices may readily use embodiments of the present disclosure. Furthermore, devices may readily use embodiments of the present disclosure regardless of their intent to provide mobility.

[0226] In an embodiment in which the device is provided in the UE 110, the device at least one processor 12; at least one memory 13 containing computer program code; Equipped with The at least one memory 13 stores instructions that, when executed by the at least one processor 12, cause the device to at least: establishing a connection towards a radio access network; A UE context modification request from a central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, including: implementing the requested changes in lower layer configuration; sending a confirmation to the central node that the requested changes have been implemented; Sending the identifier to the distributed node; Make them do so.

[0227] In an embodiment in which the device is located within a distributed node 220, the device: at least one processor 12; at least one memory 13 containing computer program code; Equipped with The at least one memory 13 stores instructions that, when executed by the at least one processor 12, cause the device to at least: A first user equipment, UE, context modification request sent from a central node towards a distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a first UE context modification request, a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and identifier receiving a second UE context modification request, sending a second UE context modification request to the UE; receiving an identifier from the UE; Make them do so.

[0228] In an embodiment in which the device is provided in the central node 220, the device: at least one processor 12; at least one memory 13 containing computer program code; Equipped with The at least one memory 13 stores instructions that, when executed by the at least one processor 12, cause the device to at least: generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: A request to modify at least a portion of the lower layer; and identifier a first user equipment, UE, sending a context modification request towards a distributed node; A second UE context modification request, A request to change at least a portion of the lower layer configuration; and identifier sending a second UE context modification request to the UE, the second UE context modification request including: Make them do so.

[0229] According to some embodiments of the present disclosure, a system is provided that includes at least one UE 110, at least one DU 220, and / or at least one CU 210.

[0230] The embodiments described above have application in telecommunications systems; tracking systems; automotive systems; electronic systems, including consumer electronic products; distributed computing systems; media systems for generating or rendering media content, including audio, visual, and audiovisual content, and mixed, mediated, virtual, and / or augmented reality; personal systems, including personal health or fitness systems; navigation systems; user interfaces, also known as human-machine interfaces; networks, including cellular, non-cellular, and optical networks; ad hoc networks; the Internet; the Internet of Things (IOT); Vehicle-to-Everything (V2X); virtualized networks; and as usable components of related software and services.

[0231] 9 illustrates a computer program 14 that may be conveyed via a distribution mechanism 20. The distribution mechanism 20 can be any suitable distribution mechanism, e.g., a machine-readable medium, a computer-readable medium, a non-transitory computer-readable storage medium, a computer program product, a memory device, a solid-state memory, a recording medium such as a Compact Disc Read-Only Memory (CD-ROM) or a Digital Versatile Disc (DVD), or an article of manufacture that comprises or tangibly embodies the computer program 14. The distribution mechanism can be a signal configured to reliably transfer the computer program. A device can receive, propagate, or transmit the computer program as a computer data signal.

[0232] In certain embodiments of the present disclosure, a computer program is provided that includes instructions that, when executed by an apparatus (such as the UE 110), cause the apparatus to perform or to cause the apparatus to perform at least the following: establishing a connection to a radio access network; A UE context modification request from a central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, including: implementing the requested changes in lower layer configuration; sending a confirmation to the central node that the requested changes have been implemented; Sending the identifier to the distributed node; is.

[0233] In certain embodiments of the present disclosure, a computer program is provided that includes instructions that, when executed by an apparatus (such as the DU 220), cause the apparatus to perform or to perform at least the following: A first user equipment, UE, context modification request sent from a central node towards a distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a first UE context modification request, a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and identifier receiving a second UE context modification request, sending a second UE context modification request to the UE; receiving an identifier from the UE; is.

[0234] In certain embodiments of the present disclosure, a computer program is provided that includes instructions that, when executed by an apparatus (such as CU 210), cause the apparatus to perform or to perform at least the following: generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: A request to modify at least a portion of the lower layer; and identifier a first user equipment, UE, sending a context modification request towards a distributed node; A second UE context modification request, A request to change at least a portion of the lower layer configuration; and identifier sending a second UE context modification request to the UE, the second UE context modification request including: is.

[0235] References to a "computer program," "computer-readable storage medium," "computer program product," "tangibly embodied computer program," etc., or to a "controller," "computer," "processor," etc., should be understood to encompass computers having different architectures, such as single / multi-processor architectures and sequential (Von Neumann) / parallel architectures, as well as special purpose circuitry, such as field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), signal processing devices, and other processing circuitry. References to a computer program, instructions, code, etc., whether instructions for a processor or configuration settings for a fixed function device, gate array, or programmable logic device, etc., should be understood to encompass software for a programmable processor or firmware, e.g., the programmable content of a hardware device.

[0236] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware-only circuit implementation (e.g., an implementation using only analog and / or digital circuitry); and (b) Combinations of hardware circuitry and software, such as (where applicable): (i) a combination of analog and / or digital hardware circuitry with software / firmware, and (ii) any portion of a hardware processor (including a digital signal processor) with software, software, and memory that works together to cause a device, such as a mobile phone or server, to perform various functions; and (c) A hardware circuit and / or processor, such as a microprocessor or portion of a microprocessor, that requires software (e.g., firmware) to operate, but the software may not be present when not required for operation.

[0237] This definition of circuitry applies to all uses of the term in this disclosure, including in any claims. As a further example, as used in this disclosure, the term circuitry also covers merely hardware circuits or processors and their (or their) accompanying software and / or firmware implementations. The term circuitry also covers, for example, baseband integrated circuits for mobile devices or similar integrated circuits in servers, cellular network devices, or other computing or network devices, if applicable to particular claim elements.

[0238] Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0239] Features described in the preceding description may be used in combinations other than those explicitly described.

[0240] Although functions have been described with reference to particular features, these functions may be implemented by other features, whether or not described.

[0241] Although features have been described with reference to particular embodiments, these features may be present in other embodiments whether or not described. Thus, a feature described in connection with one embodiment / aspect of the present disclosure may include any or all of the features described in connection with another embodiment / aspect of the present disclosure, and vice versa, to the extent that they are not mutually inconsistent.

[0242] While various embodiments of the present disclosure have been described in the preceding sections, it should be appreciated that modifications to the given embodiments may be made without departing from the scope of the present disclosure as defined in the claims. For example, while embodiments of the present disclosure have been discussed with respect to UE handover / cell switching (e.g., L1 / L2-based inter-cell mobility, etc.), it is appreciated that embodiments of the present disclosure are not limited to such applications / procedures and L1 / L2-based inter-cell mobility, but may also apply to other applications / procedures involving lower layer reconfiguration (e.g., Layer 1 or Layer 2 configuration changes).

[0243] The term "comprise" is used in this document in an inclusive rather than exclusive sense, i.e., any reference to X comprising Y indicates that X may comprise only one Y or may comprise two or more Y. Where it is intended to use "comprise" in the exclusive sense, this will be made clear in the context by a reference to "comprising only one" or by using "consisting".

[0244] In this description, the terms "connect," "couple," and "communication," as well as derivatives thereof, mean operatively connected / coupled / in communication. It should be recognized that any number or combination of intermediate components (including no intermediate components) can be present, i.e., to provide a direct or indirect connection / coupling / communication. Any such intermediate components can include hardware and / or software components.

[0245] As used herein, "determine / determining" (and grammatical variations thereof) can include, among other things, calculating, computing, processing, deriving, measuring, investigating, identifying, looking up (e.g., looking in a table, database, or another data structure), ascertaining, and the like. Similarly, "determining" can include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), obtaining, and the like. Similarly, "determining" can include resolving, selecting, choosing, establishing, and the like.

[0246] In this description, reference has been made to various embodiments. A description of features or functions associated with an embodiment indicates that these features or functions are present in that embodiment. Use of the terms "example" or "for example" or "can" or "may" in the text, whether explicitly stated or not, indicates that such features or functions are present in at least the described embodiment, whether or not they are described as an embodiment, and that they may, but are not necessarily, present in some or all other embodiments. Thus, "example," "for example," "can," or "may" refers to a particular instance within a class of embodiments. Properties of an instance can be properties of only that instance or of the class or of a subclass of the class that includes some but not all of the instances within the class.

[0247] In this description, references to the terms "a / an / the" (feature, element, component, means...) are used in an inclusive rather than an exclusive sense and are to be interpreted as "at least one" (feature, element, component, means...) unless expressly stated otherwise. That is, any reference to X comprising a / the Y indicates that X may comprise only one Y or may comprise two or more Ys, unless the context clearly dictates to the contrary. If the use of "a" or "the" in an exclusive sense is intended, this will be made clear in the context. In some circumstances, the use of "at least one" or "one or more" may be used to emphasize an inclusive sense, but the absence of these terms should not be considered to infer any exclusive sense.

[0248] The presence of a feature (or combination of features) in a claim is a reference to the feature (or combination of features) itself, and similarly to features that achieve substantially the same technical effect (equivalent features). Equivalent features include, for example, features that are modifications and achieve substantially the same result in substantially the same way. Equivalent features include, for example, features that perform substantially the same function in substantially the same way to achieve substantially the same result.

[0249] In this description, reference has been made to various embodiments using adjectives or adjective phrases to describe features of the embodiments. Such description of a feature in connection with an embodiment indicates that the feature is present in some embodiments exactly as described and in other embodiments substantially as described.

[0250] In the above description, the described devices alternatively or additionally comprise devices that, in some other embodiments, comprise a distributed system of devices, e.g., a client / server device system. In embodiments in which the provided devices form (or the method is performed as) a distributed system, each device forming a component and / or part of the system provides (or performs) one or more features that collectively perform embodiments of the present disclosure. In some embodiments, the device is reconfigured by an entity other than its original manufacturer to perform embodiments of the present disclosure by being provided with additional software, e.g., by a user downloading software that, when executed, causes the device to perform embodiments of the present disclosure (whether entirely by the device or as part of the system of devices described above).

[0251] The above description describes several embodiments of the present disclosure; however, those skilled in the art will recognize possible alternative structural and method features that provide equivalent functionality to the particular embodiments of such structure and features described above and that have been omitted from the above description for brevity and clarity. Nevertheless, the above description should be read as implicitly including references to such alternative structural and method features that provide equivalent functionality, unless such alternative structural or method features are expressly excluded in the above description of embodiments of the present disclosure.

[0252] While the foregoing specification has sought to draw attention to features of the embodiments of the present disclosure which are considered to be particularly important, it is to be understood that applicants may seek protection with respect to any patentable feature or combination of features described above with reference to and / or shown in the drawings, whether or not such feature is emphasized.

[0253] The embodiments of the present disclosure and the appended claims may be combined as appropriate in any manner apparent to one skilled in the art. Separate references in the description to an "example," "in some examples," and / or the like do not necessarily refer to the same embodiment, nor are they mutually exclusive, unless so stated and / or otherwise readily apparent to one skilled in the art from the description. For example, a feature, structure, process, block, step, action, or the like described in one embodiment may, but is not necessarily, included in other embodiments.

[0254] Each and every claim is incorporated herein as further disclosure, and the claims are embodiments of the present disclosure. Furthermore, although the claims herein are provided as including certain dependencies, to the extent that any claim depends on any other claim, and any alternative embodiment can be obtained by combining, integrating, and / or omitting features of various claims and / or changing claim dependencies, any such alternative embodiments and their equivalents are also contemplated to be within the scope of the present disclosure.

Claims

1. A radio access network (RAN) comprising at least a central node and distributed nodes, a user equipment (UE) for accessing the RAN, wherein the central node controls the distributed nodes, and the UE: at least one processor; at least one memory for storing instructions; the instructions, when executed by the at least one processor, cause the UE to establishing a connection to the radio access network; a UE context modification request from the central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, including: implementing the requested change in the lower layer configuration; and sending a confirmation to the central node that the requested change has been implemented; transmitting the identifier towards the distributed node; UE.

2. The UE context modification request: Layer 3 protocol messages, Radio resource configuration, RRC,messages, and RRC Reconfiguration Message The UE of claim 1 , wherein the signal is received from the central node in one selected from the group consisting of:

3. The identifier is Through Layer 2 signaling, in Layer 2 protocol messages, and Medium Access Control, MAC, Control Element, CE 3. The UE according to claim 1 or 2, wherein the UE transmits a signal to the distributed node in one selected from the group consisting of:

4. The identifier is Through Layer 1 signaling, Uplink Control Information, UCI, In the channel state information, CSI, report, and Layer 1 measurement report The UE according to any one of claims 1 to 3, wherein the UE transmits a signal to the distributed node in one selected from the group consisting of:

5. 5. The UE of claim 1, wherein the UE context modification request includes an indicator for requesting the UE to confirm to the distributed node that the UE has performed the requested changes, and the UE is further configured to, based at least in part on the received indicator, send the indicator towards the distributed node for confirming to the distributed node that the UE has performed the requested changes.

6. The UE according to any one of claims 1 to 5, wherein the indicator is a flag or the identifier.

7. The identifier is an identifier for identifying the request; a multi-bit identifier, or Flags The UE according to any one of claims 1 to 6,

8. The requested change is: reconfiguring a lower layer protocol of the UE; and Coordinating Layer 1, L1, measurements performed by the UE; and reconstructing L1 measurement reports of the UE; measuring one or more beams of a target cell; reporting one or more measurements of one or more beams of the target cell; The UE according to any one of claims 1 to 7, comprising a request made by the UE to at least one selected from the group consisting of:

9. 1. A method for a user equipment, UE, comprising: Establishing a connection to a radio access network, RAN, the RAN comprising at least a central node and distributed nodes, the central node controlling the distributed nodes; a UE context modification request from the central node, A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a UE context modification request, implementing the requested change in the lower layer configuration; sending a confirmation to the central node that the requested change has been implemented; and transmitting the identifier towards the distributed node; 3. A method comprising at least partially causing an action that results in:

10. A computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform the method of claim 9.

11. A distributed node of a radio access network, RAN, comprising at least a central node and the distributed node, the central node controls the distributed node, and the distributed node: at least one processor; at least one memory for storing instructions; the instructions, when executed by the at least one processor, cause the distributed node to a first user equipment, UE, context modification request sent from the central node towards the distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request a first user equipment (UE) receiving a context modification request; a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and said identifier receiving a second UE context modification request, sending the second UE context modification request towards the UE; receiving the identifier from the UE; Distributed nodes.

12. The distributed node of claim 11 , further configured to determine that the UE has implemented the requested change based at least in part on the identifier received from the UE.

13. 13. The distributed node of claim 11 or 12, further configured to send a response to the first UE context modification request towards the central node.

14. The distributed node of claim 13 , wherein the response to the first UE context modification request includes the identifier or an exchange identifier for identifying the request.

15. The distributed node receiving a confirmation from the UE for transmission to the central node that the requested change has been implemented; sending said confirmation towards said central node; The distributed node of any one of claims 11 to 14, further configured to:

16. The first UE context modification request comprises: reconfiguring a lower layer protocol of the UE; and adjusting the interpretation of Layer 1, L1, measurement reports received from the UE; receiving L1 measurements for a target cell from the UE; Associating one or more measurements from a measurement report received from the UE with one or more beams of a target cell; The UE, a target cell controlled by the distributed node; a target cell controlled by another distributed node; and One or more candidate target cells and handing over to at least one selected from the group The distributed node of any one of claims 11 to 15, comprising a request to perform at least one or more of the following:

17. the first UE context modification request includes a plurality of requested changes to the lower layer configuration; the identifier is configured to identify the plurality of requested modifications; or A distributed node according to any one of claims 11 to 16, wherein the identifiers comprise a plurality of identifiers each configured to identify the plurality of requested changes.

18. The distributed nodes are and / or - adjusting the interpretation of Layer 1, L1, measurement reports received from the UE based at least in part on the identifier received from the central node; Associating one or more measurements from a measurement report received from the UE with one or more beams of a target cell based at least in part on the identifier received from the central node. The distributed node according to any one of claims 11 to 17, further configured to:

19. The distributed node determines, based at least in part on the identifier received from the UE, that one or more L1 measurements received from the UE: target cell, one or more candidate target cells; one or more beams of the target cell; and One or more beams of one or more candidate target cells The distributed node of any one of claims 11 to 18, further configured to determine whether it is associated with at least one selected from the group:

20. The distributed node the identifier received from the UE; and an L1 measurement report received from the UE following receipt of the identifier from the UE; 20. The distributed node of claim 11, further configured to: determine to trigger the UE to perform a handover of the UE to a target cell based at least in part on at least one selected from the group:

21. A method for a distributed node of a radio access network (RAN), comprising at least a central node and the distributed nodes, wherein the central node controls the distributed nodes, the method comprising: a first user equipment, UE, context modification request sent from the central node towards the distributed node, comprising: A request to change at least a portion of the lower layer configuration; and An identifier associated with the request receiving a first UE context modification request, a second UE context modification request sent from the central node towards the UE via the distributed node, A request to change at least a portion of the lower layer configuration; and said identifier receiving a second UE context modification request, sending the second UE context modification request towards the UE; receiving the identifier from the UE; 3. A method comprising at least partially causing an action that results in:

22. 22. A computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform the method of claim 21.

23. A radio access network (RAN) comprising at least a central node and distributed nodes, the central node of the RAN controlling the distributed nodes, the central node comprising: at least one processor; at least one memory for storing instructions; the instructions, when executed by the at least one processor, cause the distributed node to generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: the request to modify at least a portion of a lower layer; and said identifier a first user equipment, UE, sending a context modification request towards the distributed node; A second UE context modification request, A request to change at least a portion of the lower layer configuration; and said identifier sending a second UE context modification request to the UE, the second UE context modification request including: Let the central node.

24. 24. The central node of claim 23, wherein the central node is further configured to receive a confirmation from the UE that the requested change has been implemented.

25. A method for a central node of a radio access network (RAN) comprising at least the central node and distributed nodes, the central node controlling the distributed nodes, the method comprising: generating an identifier associated with a request to modify at least a portion of a lower layer configuration; A first user equipment (UE) context modification request, comprising: the request to modify at least a portion of a lower layer; and said identifier sending a first UE context modification request towards the distributed node, comprising: A second UE context modification request, A request to change at least a portion of the lower layer configuration; and said identifier sending a second UE context modification request to the UE, the second UE context modification request including:

3. A method comprising at least partially causing an action that results in:

26. 26. A computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform the method of claim 25.

27. A system comprising a UE according to any one of claims 1 to 8 and a distributed node according to any one of claims 11 to 20.

28. 28. The system of claim 27, further comprising a central node according to claim 23 or 24.

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