Partial RRC decoding

Abstract

The present disclosure relates to a user equipment, a method for communication, a network node, a computer program. The user equipment comprises means for decoding and applying the received cell change measurement configuration prior to decoding the received cell change configuration. Wherein the cell changes the measurement configuration to provide measurement parameters specifying measurements to be performed for managing the handover. And wherein the cell change configuration provides handover enabled cell parameters.

Description

Technical Field

[0001] Examples of the present disclosure relate to handovers. Some examples relate to low-latency handovers, such as low-layer triggered handovers. Background Art

[0002] Handover transfers an ongoing communication session of a User Equipment (UE) from one cell to another in a connected state. Handover is used to provide continuity of service to the user, especially when the user is mobile.

[0003] Historically, cell level mobility has been configured at layer 3 (e.g., radio resource control, RRC). The network controls UE mobility based on UE measurement reports. The trigger for completing the handover can be the network, or in the case of conditional handover, the trigger for completing the handover can be the user equipment. The user equipment performs a conditional handover only if the execution conditions configured by the network are met. The decision to trigger or configure the handover is made based on layer 3 measurements.

[0004] Dual Active Protocol Stack (DAPS) handover allows the user equipment to initiate a handover to a target cell by activating two protocol stacks (one for the source cell and the other for the target cell) while maintaining a connection with the source cell.

[0005] Low layer triggered mobility (LTM) implements switching based on L1 / L2 signaling while maintaining the configuration of the higher layer and / or minimizing the configuration changes of the lower layer. The network triggers LTM cell switching by sending a MAC control element (CE) to the UE. According to the current proposal, the MAC CE indicates a cell change configuration, which is previously prepared by the network and provided to the UE via layer 3 (RRC) signaling. The cell change configuration can only be added, modified and released by the network via RRC signaling. In some examples, the network receives an L1 / L2 measurement report from the UE and changes the UE's serving cell via a MAC CE in response to a cell switching command.

[0006] LTM supports both intra-distributed unit (DU) and intra-central unit (CU)-inter-DU mobility. As proposed, the trigger for the LTM handover procedure is in the DU and the DU sends the MAC CE for LTM handover, but the entire setup for LTM cell handover is performed via the CU and sent to the UE via the RRC reconfiguration message. The RRC reconfiguration message sent contains the measurement configuration and cell change configuration for all cells that have been configured with LTM. The RRC reconfiguration message is decoded at the UE. Summary of the invention

[0007] According to various but not necessarily all examples, there is provided a user equipment comprising means for:

[0008] decoding and applying the received cell change measurement configuration before decoding the received cell change configuration,

[0009] wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing the handover, and

[0010] The cell change configuration provides cell parameters that enable handover.

[0011] In some but not necessarily all examples, the user equipment includes components for:

[0012] decoding the received cell change measurement configuration; performing measurements according to the received cell change measurement configuration; and decoding the received cell change configuration dependent on the measurements.

[0013] In some but not necessarily all examples, the user equipment includes components for:

[0014] Determining to initiate a handover with a candidate cell; and decoding a received cell change configuration for the candidate cell based on the determination.

[0015] In some but not necessarily all examples, the user equipment includes components for:

[0016] Depending on the measurements performed, a Low Layer Triggered Mobility (LTM) measurement report is sent to the network.

[0017] In some but not necessarily all examples, the user equipment includes components for:

[0018] The decoding of the received cell change measurement configuration is confirmed to the network, and / or the decoding of the received cell change configuration is confirmed to the network.

[0019] In some but not necessarily all examples, the user equipment includes components for:

[0020] A first message including a cell change measurement configuration and a second message including a cell change configuration are received from a network.

[0021] In some but not necessarily all examples, the user equipment includes components for:

[0022] decoding the received cell change measurement configuration; performing measurements according to the cell change measurement configuration; sending a measurement report to the network depending on the measurements; and decoding the cell change configuration.

[0023] In some but not necessarily all examples, the measurement report is a low layer triggered mobility (LTM) measurement report.

[0024] In some but not necessarily all examples, the measurement report identifies one or more cells and the second message includes a cell change configuration for each of the identified one or more cells.

[0025] In some but not necessarily all examples, the user equipment includes means for: decoding the first message upon receipt, and / or decoding the second message upon receipt.

[0026] In some but not necessarily all examples, the user equipment comprises means for receiving a message from the network comprising a cell change measurement configuration and a cell change configuration.

[0027] In some but not necessarily all examples, the message includes layer 3 radio resource control (RRC) information.

[0028] In some but not necessarily all examples, the user equipment comprises means for performing a UE triggered cell change using measurements made in accordance with a cell change measurement configuration.

[0029] In some but not necessarily all examples, the message includes:

[0030] A data structure comprising: a first information element, the first information element comprising a cell change measurement configuration, wherein the cell change measurement configuration provides parameters that specify measurements to be performed for managing a handover; and a plurality of second information elements, wherein each of the plurality of second information elements comprises a cell change configuration for one of a plurality of candidate cells, and wherein the cell change configuration provides parameters for enabling a handover with one of the plurality of candidate cells.

[0031] According to various but not necessarily all examples, a method is provided, the method comprising: decoding and applying a received cell change measurement configuration before decoding the received cell change configuration, wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing handover, and wherein the cell change configuration provides cell parameters that enable handover.

[0032] According to various but not necessarily all examples, a computer program is provided which, when executed by one or more processors, causes: decoding and applying a received cell change measurement configuration prior to decoding a received cell change configuration, wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing handover, and wherein the cell change configuration provides cell parameters that enable handover.

[0033] According to various but not necessarily all examples, a network node is provided, the network node comprising components for: sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing handover; and separately sending a cell change configuration to the user equipment, wherein the cell change configuration provides cell parameters that enable handover.

[0034] In some but not necessarily all examples, the network node is configured to send a first message comprising a cell change measurement configuration and separately send a second message comprising the cell change configuration.

[0035] In some but not necessarily all examples, the network node is configured to selectively send a cell change configuration to the user equipment in response to receiving a measurement report identifying a cell for managing handover from the user equipment, the cell change configuration being used to enable a cell change to the identified cell, or

[0036] The network node is configured to, in response to receiving a measurement report identifying a subset of cells for managing handover from the user equipment, selectively send to the user equipment a cell change configuration for enabling a cell change to each cell in the identified subset of cells.

[0037] In some but not necessarily all examples, the network node is configured to receive a message including a cell change measurement configuration and a cell change configuration for a plurality of cells; and the network node is configured to send the received cell change measurement configuration to the user equipment instead of the received cell change configuration; and the network node is configured to selectively send the cell change configuration to the user equipment, the cell change configuration being used to enable a cell change to a subset of cells.

[0038] In some but not necessarily all examples, the network node is configured to selectively send a cell change configuration to the user equipment in response to receiving a measurement report from the user equipment identifying a subset of multiple cells for managing handover, the cell change configuration being used to enable a cell change to each cell in the identified subset of cells.

[0039] In some but not necessarily all examples, the received message includes a data structure comprising: a first information element, the first information element comprising a cell change measurement configuration, wherein the cell change measurement configuration provides parameters that specify measurements to be performed for managing handover; and a plurality of second information elements, wherein each of the plurality of second information elements comprises a cell change configuration for one of a plurality of candidate cells, wherein the cell change configuration provides parameters for enabling handover with one of the plurality of candidate cells.

[0040] In some but not necessarily all examples, the received message includes mapping information including a one-to-one mapping for each cell change measurement configuration that maps the cell change measurement configuration to a cell identifier, thereby eliminating the need to decode the cell change measurement configuration.

[0041] In some but not necessarily all examples, the network nodes are configured as distributed units.

[0042] According to various but not necessarily all examples, a method is provided, the method comprising:

[0043] sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover; and

[0044] A cell change configuration is sent separately to the user equipment, wherein the cell change configuration provides cell parameters enabling handover.

[0045] According to various but not necessarily all examples, there is provided a computer program which, when executed by one or more processors of a network, causes:

[0046] sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover; and

[0047] A cell change configuration is sent separately to the user equipment, wherein the cell change configuration provides cell parameters enabling handover.

[0048] According to various but not necessarily all examples, examples are provided as claimed in the appended claims.

[0049] According to various but not necessarily all examples, there is provided a user equipment comprising means for:

[0050] decoding and using the received cell change measurement configuration before decoding the received cell change configuration,

[0051] wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for the purpose of managing a change in a serving cell, and

[0052] Therein the cell change configuration provides cell parameters that enable a change in the serving cell.

[0053] According to various but not necessarily all examples, there is provided a user equipment comprising means for:

[0054] receiving a first message including a cell change measurement configuration from a network,

[0055] decoding the received cell change measurement configuration, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover;

[0056] Performing measurements according to cell change measurement configuration;

[0057] Depending on the measurement, sending a measurement report to the network;

[0058] receiving a second message including at least a cell change configuration from the network; and

[0059] A cell change configuration is decoded, wherein the cell change configuration provides cell parameters that enable handover.

[0060] In some but not necessarily all examples, the measurement report identifies one or more cells, and the received second message includes a cell change configuration for each of the identified one or more cells.

[0061] In some but not necessarily all examples, the user equipment includes components for:

[0062] The first message is decoded upon receipt, and / or the second message is decoded upon receipt.

[0063] According to various but not necessarily all examples, there is provided a network node comprising means for:

[0064] sending a first message including a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for the purpose of managing a change of a serving cell;

[0065] receiving a measurement report based on measurements for the purpose of managing a change in a serving cell, the measurements being performed at a user equipment in accordance with a received cell change measurement configuration;

[0066] According to the measurement report, a second message including at least a cell change measurement configuration is sent to the user equipment.

[0067] In some but not necessarily all examples, the measurement report identifies one or more cells and the second message includes a cell change configuration for each of the identified one or more cells.

[0068] In some but not necessarily all examples, the network node is configured to separate a data structure into a first message and a second message, the data structure comprising:

[0069] a first information element, the first information element comprising a cell change measurement configuration; and

[0070] A plurality of second information elements, wherein each second information element comprises a cell change configuration for a candidate cell, wherein the cell change configuration provides parameters enabling a change into a serving cell of the respective candidate cell.

[0071] According to various but not necessarily all examples, there is provided a data structure for enabling low layer triggered mobility (LTM), the data structure comprising:

[0072] a first information element, the first information element comprising a cell change measurement configuration,

[0073] wherein the cell change measurement configuration provides parameters specifying measurements to be performed for managing the handover; and

[0074] A plurality of second information elements, wherein each second information element of the plurality of second information elements comprises a cell change configuration for one of the plurality of cells, wherein the cell change configuration provides parameters for enabling a handover with the one of the plurality of cells.

[0075] In some but not necessarily all examples, the data structure comprises a third information element comprising information about a conditional handover condition for a UE-triggered change in serving cell.

[0076] In some, but not necessarily all, examples, the data structure includes an information element that includes information for identifying conditions (and pointers) for decoding identified portions of the data structure.

[0077] Although the above examples and optional features of the present disclosure are described separately, it should be understood that their provision in all possible combinations and arrangements is included in the present disclosure. It should be understood that various examples of the present disclosure may include any or all of the features described for other examples of the present disclosure, and vice versa. In addition, it should be understood that any one or more or all of the features, in any combination, can be implemented / included in / can be executed by devices, methods and / or computer program instructions as needed and appropriate. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Some examples will now be described with reference to the accompanying drawings, in which:

[0079] Figure 1 An example of the subject matter described herein is shown;

[0080] Figure 2 Another example of the subject matter described herein is shown;

[0081] Figure 3 Another example of the subject matter described herein is shown;

[0082] Figure 4 Another example of the subject matter described herein is shown;

[0083] Figure 5 Another example of the subject matter described herein is shown;

[0084] Figure 6 Another example of the subject matter described herein is shown;

[0085] Fig. 7A , Figure 7B , Figure 7C An example of the subject matter described herein is shown;

[0086] Fig. 8A , Figure 8B , Figure 8C An example of the subject matter described herein is shown;

[0087] Fig. 9 Another example of the subject matter described herein is shown;

[0088] Fig.10 Another example of the subject matter described herein is shown;

[0089] Fig.11 Another example of the subject matter described herein is shown;

[0090] Fig.12 Another example of the subject matter described herein is shown;

[0091] Fig.13 Another example of the subject matter described herein is shown;

[0092] Fig.14 Another example of the subject matter described herein is shown.

[0093] These figures are not necessarily drawn to scale. For clarity and conciseness, certain features and views in the drawings may be shown schematically or enlarged in scale. For example, the dimensions of some elements in the drawings may be enlarged relative to other elements to aid in illustration. Similar reference numerals are used in the drawings to designate similar features. For clarity, all reference numerals may not necessarily be shown in all drawings.

[0094] In the following description, a reference number without a subscript index (e.g., 20) may be used to refer to a class (or collection), a reference number with a numeric type subscript index (e.g., 20_1) may be used to refer to a specific instance of the class (a member of the collection), and a reference number with a variable type subscript index (e.g., 20_i) may be used to refer to a non-specific instance of the class (a member of the collection). DETAILED DESCRIPTION

[0095] An example of a user equipment 110 is disclosed below, the user equipment comprising means 220 for decoding and applying a received cell change measurement configuration 10 before decoding 222 the received cell change configuration 20, wherein the cell change measurement configuration 10 provides measurement parameters specifying measurements to be performed for managing a handover, and wherein the cell change configuration 20 provides cell parameters to enable a handover.

[0096] Disclosed below in some examples are network nodes 120, 304, which include:

[0097] means for sending a cell change measurement configuration 10 to the user equipment 110, wherein the cell change measurement configuration 10 provides measurement parameters specifying measurements to be performed for managing handover; and means for separately sending a cell change configuration 20 to the user equipment 110, wherein the cell change configuration 20 provides cell parameters enabling handover.

[0098] The term "decoding" as applied to "configuration" means processing a data structure to obtain information. For example, the data structure may have a defined format that is used to convey information. In some examples, the data structure includes a hierarchy of information elements. For example, a markup language, such as extensible markup language (XML), may be used to define the hierarchy of information elements. For example, the data structure may have a defined format for conveying information, such as Abstract Syntax Notation One (ASN.1) or a similar format.

[0099] Figure 1An example of a network 100 is illustrated, which includes a plurality of network nodes, including a terminal node 110, an access node 120, and one or more core nodes 129. The terminal node 110 and the access node 120 are in communication with each other. The one or more core nodes 129 are in communication with the access node 120.

[0100] In this example, the network 100 is a radio communication network in which at least some of the terminal nodes 110 and the access nodes 120 communicate with each other using transmission / reception of radio waves.

[0101] In some examples, one or more core nodes 129 can communicate with each other. In some examples, one or more access nodes 120 can communicate with each other.

[0102] The network 100 may be a cellular network including a plurality of cells 122, each cell being served by an access node 120. In this example, the interface between the terminal node 110 and the access nodes 120 defining the cells 122 is a wireless interface 124.

[0103] The access node 120 is a cellular radio transceiver. The terminal node 110 is a cellular radio transceiver.

[0104] In the illustrated example, the cellular network 100 is a 3rd Generation Partnership Project (3GPP) network, in which the terminal nodes 110 are user equipments (UEs) and the access nodes 120 are base stations.

[0105] In the illustrated example, the network 100 is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The E-UTRAN consists of E-UTRAN NodeBs (eNBs) 120, providing E-UTRA user plane and control plane (RRC) protocol terminations toward the UE 110. The eNBs 120 are connected to each other by means of an X2 interface 126. The eNBs are also connected to a Mobility Management Entity (MME) 129 by means of an S1 interface 128.

[0106] In other examples, the network 100 is a Next Generation (or New Radio, NR) Radio Access Network (NG-RAN). The NG-RAN consists of gNodeBs (gNBs) 120, providing user plane and control plane (RRC) protocol terminations toward the UE 110. The gNBs 120 are connected to each other via an X2 / Xn interface 126. The gNBs are also connected to an Access and Mobility Management Function (AMF) via an N2 interface 128.

[0107] User equipment includes mobile devices. When a user equipment is referenced, the reference includes and contains a reference to the mobile device as much as possible.

[0108] Figure 2 An example of a user equipment 110 is illustrated comprising means 220 for decoding and applying a received cell change measurement configuration 10 before decoding 222 the received cell change configuration 20 .

[0109] The user equipment 110 further comprises means 222 for decoding and applying the received cell change configuration 20 after decoding and applying 222 the received cell change measurement configuration 10 .

[0110] The cell change measurement configuration 10 provides measurement parameters that specify measurements to be performed for managing handover. Applying the cell change measurement configuration 10 involves making one or more measurements in accordance with the measurement parameters. The cell change configuration 20 provides cell parameters that enable handover.

[0111] The decoding and application of the received cell change configuration 10 may for example depend on applying the decoded received cell change measurement configuration 10 .

[0112] The user equipment 110 may, for example, enable low latency triggered mobility (LTM), which enables serving cell change (handover) via low latency signaling. Once the handover is triggered, the delay in the handover may, for example, be less than 10 ms.

[0113] For example, user equipment 110 may enable low layer triggered mobility (LTM). This may enable cell changes via lower level signaling (eg, below layer 3). Network 120 may trigger LTM cell switching by sending a MAC control element (CE) to the UE.

[0114] The user equipment 110 further comprises means for receiving a cell change measurement configuration 10 and a cell change configuration 20. Rather than decoding the cell change measurement configuration 10 and the cell change configuration 20 simultaneously, the cell change measurement configuration 10 is first decoded and applied to enable measurements for managing handover. The separation of the decoding of the cell change measurement configuration 10 and the cell change configuration 20 allows them to be transmitted separately or not separately.

[0115] Figure 3 An example of transmitting the cell change measurement configuration 10 and the cell change configuration 20 together or separately before decoding 220 the received cell change measurement configuration 10 is illustrated.

[0116] The user equipment 110 is configured to receive a first message including a cell change measurement configuration 10 and a second message including a cell change configuration 20 from the network 120 .

[0117] The user equipment 110 is configured to decode 220 the received cell change measurement configuration 10 and then perform measurements according to the cell change measurement configuration 10 .

[0118] In some examples, the user equipment 110 is configured to selectively decode one of a plurality of cell change configurations 20 depending on the measurements.

[0119] In some examples ( Figure 3 The user equipment 110 is configured to send a measurement report 30 to the network 120 depending on the measurement. The measurement report 30 reports the measurement performed according to the cell change measurement configuration 10 for the cell change triggered by the network. In some examples, the user equipment 110 is configured to selectively decode one of the multiple cell change configurations 20 depending on the measurement report 30.

[0120] Figure 4 An example in which the cell change measurement configuration 10 and the cell change configuration 20 are transmitted separately is illustrated.

[0121] The cell change measurement configuration 10 is sent before decoding and applying 220 the received cell change measurement configuration 10. The cell change configuration 20 is sent after decoding and applying 220 the received cell change measurement configuration 10.

[0122] The user equipment 110 is configured to receive a first message including a cell change measurement configuration 10 from the network 120 and separately receive a second message including a cell change measurement configuration 20 after decoding and applying 220 the cell change measurement configuration 10 .

[0123] exist Figure 4 In the embodiment, the user equipment 110 is configured to receive a first message including a cell change measurement configuration 10 from the network 120, and decode the received cell change measurement configuration 10. The cell change configuration 20 is not decoded. The user equipment 110 is configured to perform measurements according to the cell change measurement configuration 10, and, depending on the measurements, send a measurement report 30 to the network reporting the measurements. The cell change configuration 20 is sent as a reply to the measurement report 30. The user equipment 110 is configured to receive a second message including one or more cell change configurations 20 from the network 120, and decode and use at least one cell change configuration 20.

[0124] See also Figure 3 and Figure 4 Both, in some examples, the user equipment 110 is configured to decode the cell change configuration 20 only when needed, rather than decoding in advance when decoding the cell change measurement configuration 10. In some examples, the user equipment 110 is configured to decode the received cell change configuration 20 for the candidate cell only when it is necessary to change the serving cell to the candidate cell.

[0125] See also Figure 3 and Figure 4Both, in some examples, the user equipment 110 is configured to decode the received cell change measurement configuration 10 and perform measurements according to the received cell change measurement configuration 10; and decode the received cell change configuration 20 depending on the measurements. Figure 3 In , the cell change configuration 20 has been received. Figure 4 In the embodiment, as a reply to the measurement report 30, a cell change configuration 20 is received.

[0126] In at least some examples, the measurement report 30 is a low layer triggered mobility (LTM) measurement report 30 , such as an L1 / L2 triggered mobility (LTM) measurement report 30 .

[0127] In at least some examples, the measurement report 30 identifies one or more cells, and the subsequent second message includes the cell change configuration 20 for each of the identified one or more cells.

[0128] In some examples, the user equipment 110 is configured to send a confirmation signal 22 to the network 120, the confirmation signal 22 confirming that the decoding 220 of the cell change measurement configuration 10 has been completed and / or confirming that the decoding 222 of the cell change configuration 20 has been completed. Figure 3 and Figure 4 In the example illustrated in , the user equipment 110 is optionally configured to send a confirmation signal 22_1 to the network 120, which confirms that the decoding 220 of the cell change measurement configuration 10 has been completed, and / or the user equipment 110 is optionally configured to send a confirmation signal 22_2 to the network 120, which confirms that the decoding 222 of the cell change configuration 20 has been completed.

[0129] In some examples, one or more cell change configurations 20 are sent in response to receiving a confirmation signal 22_1, which confirms that decoding of the cell change measurement configuration 10 has been completed. It can be appreciated that a measurement report 30 can replace the confirmation signal 22_1. The measurement report 30 confirms that the decoding of the cell change measurement configuration 10 has been decoded and applied by providing measurements.

[0130] Figure 5 An example of a network node 120 is illustrated, which is configured to send a cell change measurement configuration 10 and one or more cell change configurations 20 to a user equipment 110 .

[0131] The network node 120 is configured to send a cell change measurement configuration 10 to the user equipment 110 , and separately send a cell change configuration 20 to the user equipment 110 .

[0132] The cell change measurement configuration 10 provides measurement parameters that specify measurements to be performed for managing handover. The cell change configuration 20 provides cell parameters to enable handover.

[0133] In the illustrated example, the network node 120 is configured to send a first message including the cell change measurement configuration 10 , and separately send a second message including the cell change configuration 20 .

[0134] The network node 120 is configured to, in response to receiving a measurement report 30 for managing handover from the user equipment 110 identifying a cell, selectively send to the user equipment 110 a cell change configuration 20 for enabling a cell change to the identified cell.

[0135] The network node 120 is configured to, in response to receiving a measurement report 30 identifying a subset of cells for managing handover from the user equipment 110, selectively send to the user equipment 110 a cell change configuration 20 for enabling a cell change to each cell in the identified subset of cells.

[0136] like Figure 5 As illustrated in , in some examples, the received cell change measurement configuration 10 and the received cell change measurement configuration 20 originate from a message 310 .

[0137] The message 310 includes a cell change measurement configuration 10 and a plurality of cell change configurations (a cell change configuration 20 for each of the plurality of cells). The message 310 may be, for example, a layer 3 message such as a radio resource control (RRC) message.

[0138] In the illustrated example, the network node 120 is configured to send the received cell change measurement configuration 10 to the user equipment 110, but not to send the received cell change configuration 20; and the network node 120 is configured to selectively send the cell change configuration 20 to the user equipment 110 in response to receiving a measurement report 30 for managing handover identifying a plurality of cell subsets from the user equipment 110, the cell change configuration 20 being used to enable a cell change to each cell in the identified cell subsets.

[0139] In the illustrated example (but not necessarily in all examples), the network node 120 has a disaggregated (split) architecture. The network node 120 includes one or more distributed units (DUs) 304 and a centralized unit CU 302 .

[0140] CU 302 is a logical node configured to host the radio resource connection (RRC) layer and / or other high layers of the network node 120. CU 302 controls the operation of one or more DUs 304. DU 304 is a logical node configured to host the lower layers (radio link control (RLC) protocol layer, media access control (MAC) layer, and physical (PHY) layer) of the network node 120. DU 304 can communicate with the RRC layer hosted by CU 302 via a dedicated interface (e.g., F1 interface). One DU 304 can support one or more cells 122. DU 304 can host one or more transmit receive points (TRPs).

[0141] DU 304 sends a cell change measurement configuration 10 to UE 110 , receives a measurement report 30 from UE 110 , and sends a cell change configuration 20 to UE 110 CU 302 sends a message 310 to DU 304 .

[0142] In more detail, CU 302 obtains 320 a cell change measurement configuration 10 and a cell change configuration 20 for each target cell and sends them to DU 304 via message 310. Cell change measurement configuration 10 provides information required for UE 110 to monitor candidate target cells. As an example, this can be a measurement report configuration for LTM. Cell change configuration 20 provides information required for UE 110 to perform handover and connect to a prepared target cell.

[0143] At block 330, source DU 304_1 (which will trigger handover) stores cell change configuration 20 for the target cell. Source DU 304_1 forwards cell change measurement configuration 10 to UE 110. UE 110 decodes the received cell change measurement configuration 10 (which contains necessary information of cells that should be monitored) and performs monitoring and reporting.

[0144] Low layer (L1 / L2) triggered mobility is a low layer procedure, i.e. below layer 3, and is performed by DU 304. The triggering of this procedure is performed by DU. The setup is performed by CU. The medium access control (MAC) entity is located in DU 304. The radio resource control (RRC) entity is located in CU 302. The LTM MAC control element (CE) sent from DU 304 to UE 110 and used to trigger handover can also be used to transmit or assist in transmitting the cell change configuration 20 used in handover.

[0145] Figure 6An example of a message 310 is illustrated in . The message 310 is a data structure comprising: a first information element 322 comprising a cell change measurement configuration 10, wherein the cell change measurement configuration 10 provides parameters specifying measurements to be performed for managing a handover; and a plurality of second information elements 324, wherein each second information element 324 of the plurality of second information elements 324 comprises a cell change configuration 20 for one of a plurality of candidate cells, and wherein the cell change configuration 20 provides parameters for enabling a handover with one of the plurality of candidate cells.

[0146] The second information element 324_1 includes a cell change configuration 20_1 for a first candidate cell among the plurality of candidate cells. The cell change configuration 20_1 provides parameters enabling handover to the first candidate cell.

[0147] The second information element 324_2 includes a cell change configuration 20_2 for a second candidate cell among the plurality of candidate cells. The cell change configuration 20_2 provides parameters enabling handover to the second candidate cell.

[0148] The second information element 324_M includes a cell change configuration 20_M for an Mth candidate cell among the plurality of candidate cells. The cell change configuration 20_M provides parameters enabling handover to the Mth candidate cell.

[0149] In some examples, such as Figure 6 , message 310 includes a third information element 326. The third information element 326 identifies a condition that results in decoding the identified portion of the data structure 310 at the UE 110. In at least some examples, the third information element 326 includes mapping information 312. The mapping information 312 includes a one-to-one mapping for each cell change measurement configuration 10 that maps the cell change configuration 20 to a cell identifier.

[0150] See also Figure 5 The network node 120 is configured to, in response to receiving a measurement report 30 for managing handover from the user equipment 110, the measurement report identifying a subset of the plurality of cells using a plurality of cell identifiers, selectively send a cell change configuration 20 to the user equipment 110 to enable a cell change to each identified subset of cells.

[0151] The network node 120 maps the received cell identifier to the corresponding cell change configuration 20 of the message 310 using the mapping information 312. The network node 120 sends the corresponding cell change configuration 20 to the UE 110.

[0152] The mapping information 312 eliminates the need to decode the cell change configurations 20 in order to identify the cells to which they correspond. This information is provided in clear text in the mapping information.

[0153] In at least some examples, message 310 is a radio resource control (RRC) message.

[0154] In the illustrated example, message 310 is a splittable message. It can be stored as separate information elements. It can be transmitted to UE 110 at different times as separate information elements.

[0155] DU 304 is configured to split message 310 into a first message and a second message, the first message including a first information element 322 including a cell change measurement configuration 10; the second message including a plurality of second information elements 324, wherein each second information element 324 includes a cell change configuration 20 for a candidate cell. The cell change configuration 20 provides parameters that enable a change in the serving cell to the corresponding candidate cell.

[0156] LTM is a process in which the network node 120 receives a measurement report 30 from the UE, and on this basis, the network node 120 controls the change of the UE's (multiple) serving cells through a MAC CE. The network node 120 prepares one or more candidate cells and provides the cell change configuration 20 for the prepared candidate cells to the UE. Then, the LTM cell switching is triggered by selecting one of the cell change configurations 20 as the target configuration for LTM. The trigger for selection can be at the network node (normal switching) or at the user equipment (conditional switching). For example, the cell change configuration 20 can define information for use in a random access process for connecting to a new cell. The cell change configuration 20 can be provided as an incremental configuration (i.e., a change relative to a reference configuration) or as a fully explicit cell change configuration 20.

[0157] Fig. 7A An example is illustrated, where a cell change measurement configuration 10 and one or more cell change configurations 20_1, 20_2 are sent from a network node 120 to a user equipment 110. The user equipment 110 is configured to receive a message from the network node 120, the message comprising the cell change measurement configuration 10 and at least one cell change measurement configuration 10.

[0158] In some examples, a cell change measurement configuration 10 and a plurality of cell change configurations 20 are sent together to the user equipment 110, for example in a single message, to enable UE triggered cell change (conditional handover). The message may be, for example, a layer 3 radio resource control (RRC) message.

[0159] In some examples, the user equipment 110 is configured to perform a UE-triggered cell change using measurements performed in accordance with the cell change measurement configuration 10. In at least some examples, the user equipment is configured to determine to initiate a handover with a target candidate cell, based on which the received cell change configuration 20 for the target candidate cell is decoded.

[0160] Fig. 7A and Figure 7B An example is illustrated in which the cell change measurement configuration 10 and one or more cell change configurations 20_1 , 20_2 are sent separately from the network node 120 to the user equipment 110 .

[0161] In the illustrated example, Fig. 7A It is illustrated that a cell change measurement configuration 10 is sent from the network node 120 (DU 304) to the UE 110 without the cell change configuration 20 in the first message. Figure 7B One or more cell change configurations 20 are illustrated being sent from the network node 120 (DU 304) to the UE 110 without a cell change measurement configuration 10 in the second message. The network node 120 (DU 304) is configured to selectively send cell change configurations 20_X, 20_Y to the user equipment in response to receiving a measurement report 30 for managing handover identifying a cell subset 122_X, 122_Y from the user equipment 110 to enable a cell change to each of the identified cell subsets. In the illustrated example, the second message includes a cell change configuration 20_X for enabling a cell change to one of the identified cell subsets, and the second message includes a cell change configuration 20_Y for enabling a cell change to another of the identified cell subsets.

[0162] In at least some examples, user device 110 is configured to decode the first message upon receipt, and / or to decode the second message upon receipt.

[0163] Fig. 8A , Figure 8B , Figure 8C An example of sending a cell change configuration 20 from a network node 120 (DU 304) to a UE 110 is illustrated.

[0164] exist Fig. 8A In the embodiment of the present invention, the cell change configuration 20 is sent from the network node 120 (DU 304) to the UE 110 within a second message, which is a LTM medium access control (MAC) message. The cell change configuration 20 is radio resource control (RBB) information received at the network node 120 as part of an RRC message. The cell change configuration 20 is included within an information element within the MAC message.

[0165] exist Figure 8B In the embodiment of the present invention, the cell change configuration 20 is sent from the network node 120 (DU 304) to the UE 110 by being attached to a medium access control (MAC) message.

[0166] The cell change configuration 20 is a radio resource control (RRC) information received at the network node 120 as part of an RRC message. The cell change configuration 20 is attached to a MAC message as an RRC message.

[0167] exist Figure 8C In the LTM medium access control (MAC) message, the cell change configuration 20 is sent separately. The cell change configuration 20 is a radio resource control (RBB) information received at the network node 120 as part of an RRC message. The cell change configuration 20 is sent as an RRC message.

[0168] The message generated by the DU is an LTM MAC level message. The DU also transmits (in, attached to or separately from the MAC message) the relevant RRC segment previously obtained by the CU 302 and stored in the DU 304, which is a layer 3 message.

[0169] Composite Message( Fig. 8A , Figure 8B ) includes a MAC level message (L2) generated by DU 304 and an RRC segment provided to DU 304 by CU 302. DU 304 forwards these two messages together at the time of cell switching. In order to identify which layer 3 segment to forward (because DU 304 does not have the ability to decode these messages), DU 304 uses mapping. If DU 304 wants UE 110 to switch to cell 1, it sends a MAC level message to UE 110, which contains an instruction for UE 110 to switch to cell 1, and an RRC level message, which contains information about how the UE switches to cell 1. It depends on whether UE 110 can decode these RRC messages separately from each other.

[0170] In one implementation ( Fig. 8A ), the RRC level message is included in the LTM MAC CE. In another implementation ( Figure 8B ), the RRC level message is attached to the LTM MAC CE. In another implementation ( Figure 8C ), the RRC segment may then be sent to the LTM MAC CE. UE 110 knows that after receiving the MAC level command triggering the cell handover, it should expect an RRC segment indicating how to connect to the target cell.

[0171] The term handover is used to refer to a change in serving cell, which includes a change in serving cell associated with dual connectivity (DC).

[0172] A number of different example implementations will now be provided in the context of 3GPP New Radio. In these examples, the same references as in the previous examples will be used.

[0173] In these examples, the UE 110 decodes the content of the RRC reconfiguration message 310 in parts, i.e., the UE may decode another part of the message (e.g., cell change measurement configuration 10) at a different time than a part (e.g., cell change configuration 20). Optionally, this may also involve receiving each part 10, 20 independently. Optionally, the UE 100 indicates 22 to the network 120 the success of decoding 220, 222 of each part independently.

[0174] The cell change measurement configuration 10 provides measurement parameters that specify measurements to be performed for managing handover.

[0175] The cell change configuration 20 provides cell parameters that enable handover.

[0176] Partial decoding of the RRC message 310 at the UE 110 requires splitting the structure of the RRC message 310 sent to the UE when configuring LTM into two or more parts, such as a common part and a cell-specific part. Typically, when the RRC message 310 is split into multiple parts, each part is forwarded to the UE 110 only when it is needed. Therefore, when a specific part of the message is to be decoded, the UE 110 can be notified by receiving the part. Optionally, the network 120 can also indicate to the UE 110 whether a response to a successful decoding is required. For example, the message can have a part (cell change configuration 20) that is only used when the UE 110 (e.g., via the LTM process) switches to a specific serving cell.

[0177] Furthermore, the message structure may be such that it may be referenced via a low layer trigger: for example, the MAC CE (or DCI) may indicate applicability to a specific message segment (specific cell change configuration 20), which the UE 110 then decodes and uses in subsequent procedures to connect to the target cell.

[0178] The RRC message 310 comprises different sections including a cell change configuration 20 and a cell change measurement configuration 10 for each of the plurality of cells, e.g. Figure 6 and Fig. 7A As shown in the figure.

[0179] The RRC segment may be self-decodable. Alternatively, the segment may be decoding dependent, i.e., it can only be decoded when combined with another higher stage. The segment may be represented as a "delta" compared to the higher stage. In general, there may be multiple different segments that are either independent of each other or dependent on each other. In terms of Abstract Syntax Notation One (ASN.1), each part can be decoded independently if it is divided into independently decodable containers (e.g., using octet strings). The ASN.1 syntax may also indicate the contents of the container to allow faster decoding.

[0180] In the following example, the RRC message 310RRCPartialReconfiguration includes 1..maxRRC-Segments RRC segments packed in a segment container (i.e., OCTET STRING), and each RRC-Segment then contains one RRCReconfiguration message:

[0181] RRCPartialReconfiguration::=SEQUENCE{

[0182] rrc-Segments SEQUENCE(SIZE(1..maxRRC-Segments))OF

[0183] RRC-SegmentContainer-r18,

[0184] lateNonCriticalExtension OCTET STRING Optional,

[0185] nonCriticalExtension SEQUENCE{} Optional

[0186] }

[0187] RRC-SegmentContainer-r18::=SEQUENCE{

[0188] segment OCTET STRING(CONTAINING RRC-Segment-r18),

[0189] decodingRequested BOOLEAN

[0190] }

[0191] RRC-Segment-r18::=SEQUENCE{

[0192] rrcReconfiguration-r18 RRCReconfiguration,

[0193] lateNonCriticalExtension OCTET STRING Optional,

[0194] nonCriticalExtension SEQUENCE{} Optional

[0195] }

[0196] When LTM is set, the method does not send the entire RRC configuration message to UE 110, CU 402 only forwards the information required to monitor the cell (cell change measurement configuration 10) configured with LTM to UE 110. The information required to connect to other cells (cell change configuration 20) can be forwarded to serving DU 404 to be sent later if needed (e.g., selectively send some but not all cell change configurations 20) to UE 110.

[0197] UE 110 needs to decode the first RRC segment (cell change measurement configuration 10) provided by CU 402 because it needs information about the cell to be monitored and detailed information that needs to be reported to serving DU 402.

[0198] Then, in some examples, UE 110 may send a measurement report 30 to serving DU 402. After making the decision to trigger a cell handover, serving DU 402 may send a MAC CE command to UE 110 to switch cells and also attach an RRC segment (cell change configuration 20) containing the information needed to connect to the target cell. UE 110 decodes this message and uses the content to connect to the target cell.

[0199] These examples enable the possibility to decode the RRC reconfiguration message for LTM only in parts when needed. In addition, this has the benefit of reducing signaling and the UE 110 decodes smaller messages. This RRC splitting process is applicable to both inter-CU cases and intra-CU cases. It also applies to network-triggered handovers and UE-triggered conditional handovers.

[0200] For the situation within CU, Fig. 9 An example signaling diagram is presented in .

[0201] The signaling diagram illustrates a preparation phase, an execution phase, and a completion phase. The preparation phase prepares the UE 110 to make measurements according to the RRC cell change measurement configuration 10 and to send a measurement report 30. During the execution phase, the UE 110 makes measurements according to the received RRC cell change measurement configuration 10 and sends a measurement report 30. This triggers the transmission of the RRC cell change configuration 20 (for the cell) from the network 120 to the UE 110. During the execution phase, the UE 110 uses the received RRC cell change configuration 20 to perform a handover to the cell according to the received RRC cell change configuration 20.

[0202] The RRC cell change measurement configuration 10 is received and decoded during the preparation phase and used during the execution phase.

[0203] The RRC cell change configuration 20 is received and decoded during the execution phase and used during the completion phase.

[0204] The source DU 304_1 and the target DU 304_2 are controlled by the CU 302 .

[0205] The UE 110 forwards 801, 803 an L3 measurement report containing measurement information of the serving cell and the target cell(s). The L3 measurement report is sent 801 from the UE 110 to the source DU 304_1 and 803 from the source DU 304_1 to the CU 302, for example using UL RRC messaging. The L3 measurement report may be sent from the UE 110 to the target DU 304_2 and from the target DU 304_2 to the CU 302 (not shown).

[0206] At block 810 , the CU 302 makes a handover decision and identifies candidate target cells.

[0207] The network requests the preparation of candidate cells controlled by a DU (target DU 304_2 in this example, but the scheme is applicable to a wider range of scenarios) by sending a UE context setup request message 805. The target DU 304_2 provides the UE's configuration (cell change configuration 20) in a UE context setup response message 807. This may or may not contain UE-specific information.

[0208] The CU requests to prepare candidate cells controlled by the source DU 304_1 by sending a UE context modification request message 809. The source DU 304_1 provides 811 the configuration of the UE to the CU 302 in a context modification response message. The configuration may contain a UE-specific part and a non-UE-specific part.

[0209] After receiving all necessary information from the candidate target cells, the CU 302 prepares the source DU 304_1 to trigger the handover. The CU 302 generates 320 an RRC reconfiguration message segment (cell change measurement configuration 10 and cell change configuration 20 for each target cell). The cell change measurement configuration 10 provides the information required by the UE to monitor the candidate target cells. As an example, this may be a measurement report configuration for LTM. The cell change configuration 20 provides the information required by the UE 110 to perform a handover and connect to the prepared target cell when receiving the LTM MAC CE command to change the serving cell. Then, the RRC reconfiguration segment (cell change measurement configuration 10 and cell change configuration 20 for each target cell) is forwarded from the CU 302 to the source DU 304_1.

[0210] At block 330, the source DU 304_1 (which will trigger the handover) stores the RRC reconfiguration segment containing information on how to connect to each of the target cells (cell change configuration 20 for the target cells).

[0211] The source DU 304_1 forwards the RRC segment containing information about the target cell that needs to be monitored to the UE 110 (cell change measurement configuration 10).

[0212] The UE 110 acknowledges 22_1 receipt of the RRC reconfiguration segment to the source DU 304_1, and the source DU 304_1 sends an acknowledgement 813 to the CU 302 (eg, UL RRC messaging).

[0213] The UE 110 performs RRC reconfiguration (partial decoding) using the received cell change measurement configuration 10, which contains the necessary information of the cells that should be monitored. The UE 110 decodes the cell change measurement configuration 10 and applies it to make measurements, such as L1 beam measurements.

[0214] The UE 110 starts reporting 30 L1 beam measurements of the serving cell and candidate target cells.

[0215] After determining that there is a candidate cell with better radio conditions than the serving cell, the source DU 304_1 can forward a segment of the RRC reconfiguration message that contains only information about the target cell to which the UE should attempt to randomly access. The source DU 304_1 forwards the cell change configuration 20 for the target cell. Not all stored cell change configurations 20 are forwarded; only the required cell change configurations 20 are forwarded. The forwarding is selective. This saves the UE 110 the computational effort of decoding all cell change configurations 20 (including cell change configurations 20 containing information about candidate cells to which the UE is not connected).

[0216] At block 820, the source DU 804_1 decides to trigger a cell handover (serving cell change).

[0217] The source DU 804_1 sends a MAC CE to the UE to trigger the cell change, and sends the RRC segment required to connect to the target cell (cell change configuration 20 for the target cell).

[0218] Perform handover from the serving cell to the target cell. The UE 110 sends a random access request 821, receives a random access response 823, and then sends an RRC reconfiguration complete message 825 to the target DU 304_2, and the RRC reconfiguration complete message (e.g., transmitted using UL RRC messaging) notifies 827 the CU 802;

[0219] Release the UE context from the source DU. Perform path switching to the new serving DU. CU 802 sends 831 a context release command to the old source DU 304_1. The old source DU 304_1 replies with a context release complete message 833 to the target UE. At block 840, the path switch is complete.

[0220] For the situation within CU, Fig.10 An example signaling diagram is presented in . It is similar to Fig. 9 However, the source DU 304_1 and the target DU 304_2 are not controlled by the CU 302, but the source DU 304_1 is controlled by the source CU 302_1, and the target DU 304_2 is controlled by the target CU 302_2. Therefore, there is additional signaling 805, 827 between the source CU 302_1 and the target CU 302_2. Otherwise, the signaling is similar.

[0221] The source CU decides to configure LTM for one (or more) DUs operating within the coverage of another CU, and for the inter-CU case, enables RRC splitting of the LTM process.

[0222] The network 120 requests to prepare a candidate cell controlled by a DU (target DU 304_2 in this example, but the solution is applicable to a wider range of scenarios) by sending a UE context setup request message 805. The target DU 304_2 is controlled by the target CU 302_2, so the UE context setup request message 805 is sent in two branches, first sending 805_1 a request LTM configuration with a partial decoding message from the source CU 304_1 to the target CU 302_2, and then sending 805_2 a UE context setup request message from the target CU 302_2 to the target DU 304_2.

[0223] The target DU 304_2 provides the configuration for the UE (cell change configuration 20) in the UE context setup response message 807 sent to the source CU 302_1. This may or may not contain UE-specific information. The target DU 304_2 is controlled by the target CU 302_2, so the UE context setup response message 807 is sent in 2 branches, first sending 807_1UE context setup response message from the target DU 304_2 to the target CU 302_2, and then sending 807_2 LTM configuration with partial decoding response message from the target CU 302_2 to the source CU 302_1.

[0224] When performing a handover from a serving cell to a target cell, the UE 110 sends a random access request 821, receives a random access response 823, and then sends an RRC reconfiguration complete message 825 to the target DU 304_2. The target DU 304_2 notifies 827 the source CU 802_1. The target DU 304_2 is controlled by the target CU 302_2, so this is achieved through two branches. First, it sends 827_1LTM complete (with partial decoding) message from the target DU 304_2 to the target CU 302_2, and then sends 827_2LTM complete (with partial decoding) message from the target CU 302_2 to the source CU 302_1.

[0225] Fig.11 An example is shown where UE 110 triggers a switch (handover) to a target cell based on conditions provided by the CU. This is a form of conditional handover. Fig.11 and Fig. 9 and Fig.10 is similar and uses similar references. Fig. 9 In contrast, instead of CU 302 preparing 320, 310 source DU 304_1 to trigger a handover, CU 302 prepares 850, 310, 10, 20 UE 110 to trigger 870 a handover. Source DU 304_1 and target DU 304_2 are controlled by CU 302, as shown in FIG. Fig. 9 However, Fig.10 An arrangement is also possible.

[0226] The signaling diagram illustrates a preparation phase and an execution phase. The preparation phase prepares the UE 110 to perform measurements according to the RRC cell change measurement configuration 10 and trigger a handover according to the RRC cell change configuration 20. When the UE 110 triggers a handover, it does not need to send a measurement report to the network 120 to enable the network to trigger the handover.

[0227] During the execution phase, the UE 110 performs measurements and triggers handover. During the execution phase, the UE 110 uses the previously received RRC cell change configuration 20 to perform handover to the target cell according to the RRC cell change configuration 20.

[0228] The RRC cell change measurement configuration 10 is received and decoded during the preparation phase and used during the execution phase.

[0229] The RRC cell change configuration 20 is received during the preparation phase and decoded and used during the execution phase.

[0230] The source DU 304_1 and the target DU 304_2 are controlled by the CU 302 .

[0231] At block 850, CU 302 makes a conditional handover decision and identifies candidate target cells. CU 302 prepares UE 110 to trigger a handover.

[0232] CU 302 generates 850 an RRC reconfiguration message segment (cell change measurement configuration 10 and cell change configuration 20 for each target cell). The cell change measurement configuration 10 provides the information required for UE 110 to monitor the candidate target cells. For example, this can be a measurement report configuration for LTM. The cell change configuration 20 provides the information required for UE 110 to perform a handover and connect to the prepared target cell when it triggers a handover. Then, the RRC reconfiguration segment (cell change measurement configuration 10 and cell change configuration 20 for each target cell) is forwarded 310 from CU 302 to source DU 304_1, and source DU 304_1 forwards the cell change measurement configuration 10 and cell change configuration 20 for each target cell to UE 110.

[0233] The UE 110 (which will trigger the handover) stores the RRC reconfiguration section which contains information on how to connect to each of the target cells (cell change configuration 20 for the target cells).

[0234] The UE 110 acknowledges 22 receipt of the RRC reconfiguration segment to the source DU 304_1, which sends an acknowledgement 813 to the CU 302 (eg, UL RRC messaging).

[0235] UE 110 performs RRC reconfiguration (partial decoding) using the received cell change measurement configuration 10, which contains necessary information of cells that should be monitored. UE 110 decodes the cell change measurement configuration 10 and performs measurement and monitoring using the decoded cell change measurement configuration 10. The cell change measurement configuration 10 may include conditions for satisfying UE-triggered handover.

[0236] After determining that the handover condition for the specific cell(s) is met, the UE 110 decodes 870 only the cell change configuration(s) 20 for the conditionally selected cell(s). The UE 110 decodes only the required cell change configuration(s) 20. The cell change configuration(s) 20 that are not required because they are not related to the conditionally selected cell(s) are not decoded. This saves the UE 110 the computational effort of decoding all cell change configurations 20, including cell change configurations 20 that contain information about candidate cells to which the UE is not connected.

[0237] In some examples, UE 110 decodes the portion of the RRC message containing information on how to connect to the target cell, which may be indicated by the decodingRequested flag presented earlier. UE 110 then begins measuring the candidate cells, and when the condition is triggered (e.g., L1 RSRP of the target cell > L1 RSRP of the source cell), the UE decodes the portion of the RRC message containing information on how to connect to the target cell.

[0238] Perform handover from the serving cell to the target cell. The UE 110 sends a random access request 821, receives a random access response 823, and then sends an RRC reconfiguration complete message 825 to the target DU 304_2, which notifies 827 the CU 802 (e.g., using UL RRC messaging);

[0239] Although not illustrated in the figure, the UE context is released from the source DU and a path switch is performed to the new serving DU.

[0240] In any of the preceding examples, assistance may be provided to a layer 2 entity (eg, a UE 110 performing LTM, or a DU supporting LTM) to enable selective decoding of a subset of the cell change configurations 20 .

[0241] In the case when the network (e.g., DU 304) selectively forwards the cell change configuration 20 towards UE 110, CU 302 needs to inform DU 304 which part of the RRC reconfiguration message should be forwarded to UE 110. This eliminates the need for DU 304 to decode the entire RRC reconfiguration message. This notification can be done via a UE context modification message.

[0242] As an example, let the RRC message constructed by the CU be split into three parts (such as Fig. 7A. A mapping (which may be a dictionary, for example) is then provided by CU 302 to DU 304, which maps the cell identifier to a specific portion of the RRC reconfiguration message (appropriate cell change configuration 20). Pointers may be used to identify specific portions of the RRC reconfiguration message (e.g., the start and end points of a segment). Upon cell change, if DU 304 decides to reroute the UE to cell X, it needs to send a MAC CE command with the segment associated with cell X.

[0243] In the case where selective decoding is required by the UE 110, the approach will be similar, except that now the mapping will be provided directly (from the CU) to the UE (e.g., in an RRC reconfiguration message). Then, when a handover is triggered (by the DU or the UE), the UE will decode the relevant parts.

[0244] Fig.14 An example of a method 500 is illustrated. The method 500 may be performed at the user equipment 110, for example.

[0245] The method 500 includes, at block 502 , receiving a cell change measurement configuration 10 .

[0246] The method 500 includes decoding and applying the received cell change measurement configuration prior to decoding the received cell change configuration at block 504. The cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing handover, and the cell change configuration provides cell parameters that enable handover.

[0247] The method 500 includes, at block 506 , decoding and applying the received cell change configuration.

[0248] For example, a cell change configuration 20 may be received after block 504 .

[0249] For example, the cell change configuration 20 may be received prior to block 504 .

[0250] Fig.12 An example of a controller 400 suitable for use in devices 110, 120, 302, 304 is illustrated. An implementation of the controller 400 may be a controller circuit system. The controller 400 may be implemented solely in hardware, solely with certain aspects in software (including firmware), or may be a combination of hardware and software (including firmware).

[0251] like Fig.12As illustrated in , the controller 400 may be implemented using instructions that enable hardware functionality, such as by using executable instructions of a computer program 406 in a general or special purpose processor 402, which instructions may be stored on a computer-readable storage medium (disk, memory, etc.) for execution by such processor 402.

[0252] The processor 402 is configured to read from and write to the memory 404. The processor 402 may also include an output interface via which data and / or commands are output by the processor 402, and an input interface via which data and / or commands are input to the processor 402.

[0253] The memory 404 stores a computer program 406, which includes computer program instructions (computer program code) that control the operation of the device when loaded into the processor 402. The computer program instructions of the computer program 406 provide logic and routines that enable the device to perform the methods illustrated in the accompanying drawings. The processor 402 can load and execute the computer program 406 by reading the memory 404.

[0254] The apparatus includes: at least one processor 402; and at least one memory 404 including computer program code, wherein the at least one memory 404 and the computer program code are configured to, together with the at least one processor 402, enable the apparatus to at least perform the above functions.

[0255] In some examples, user equipment 110 includes:

[0256] at least one processor 402; and

[0257] at least one memory 404 comprising computer program code,

[0258] The at least one memory 404 stores instructions that, when executed by the at least one processor 402, cause the apparatus to at least:

[0259] decoding and applying the received cell change measurement configuration before decoding the received cell change configuration,

[0260] wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing the handover, and

[0261] The cell change configuration provides cell parameters that enable handover.

[0262] like Fig.13As illustrated in , the computer program 406 may arrive at the apparatus via any suitable delivery mechanism 408. The delivery mechanism 408 may be, for example, a machine-readable medium, a computer-readable medium, a non-transitory computer-readable storage medium, a computer program product, a storage device, a recording medium (such as a compact disk read-only memory (CD-ROM), or a digital versatile disk (DVD), or a solid-state memory), an article of manufacture containing or tangibly embodying the computer program 406. The delivery mechanism may be a signal configured to reliably transmit the computer program 406. The apparatus may propagate or send the computer program 406 as a computer data signal.

[0263] In at least some examples, computer program instructions are provided for causing user device 110 to perform at least the following operations or for performing at least the following operations:

[0264] decoding and applying the received cell change measurement configuration before decoding the received cell change configuration,

[0265] wherein the cell change measurement configuration provides measurement parameters that specify measurements to be performed for managing the handover, and

[0266] The cell change configuration provides cell parameters that enable handover.

[0267] 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. In some but not necessarily all examples, the computer program instructions may be distributed over multiple computer programs.

[0268] Although memory 404 is illustrated 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 / cached storage.

[0269] Although processor 402 is illustrated 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 402 may be a single-core or multi-core processor.

[0270] References to "computer-readable storage medium," "computer program product," "tangibly embodied computer program," etc., or "controller," "computer," "processor," etc., should be understood to cover not only computers having different architectures (such as single / multi-processor architectures and sequential (von Neumann) / parallel architectures), but also special-purpose circuits (such as field-programmable gate arrays (FPGAs), application-specific circuits (ASICs), signal processing devices, and other processing circuit systems). References to computer programs, instructions, code, etc. should be understood to cover software for a programmable processor, or firmware (such as, for example, the programmable content of a hardware device), whether instructions for a processor, or configuration settings for a fixed-function device, gate array, or programmable logic device, etc.

[0271] As used in this application, the term "circuitry" may refer to one or more or all of the following:

[0272] (a) pure hardware circuitry implementation (e.g., implementation solely in analog and / or digital circuitry) and

[0273] (b) a combination of hardware circuitry and software such as (where applicable):

[0274] (i) a combination of analog and / or digital hardware circuits and software / firmware, and

[0275] (ii) (including digital signal processor(s)) any portion of a hardware processor(s) with software, software, and one or more memories that work together to enable a device (such as a mobile phone or server) to perform various functions, and

[0276] (c) Hardware circuit(s) and / or processor(s) that require software (e.g., firmware) to operate, such as microprocessor(s) or portions of microprocessor(s), but where software is not required to operate, the software may not be present.

[0277] This definition of circuitry applies to all uses of the term in this application, including all uses of the term in any claims. As a further example, as used in this application, the term circuitry also covers implementations of hardware-only circuits or processors and their accompanying software and / or firmware. For example, and if applicable to a particular claim element, the term circuitry also covers a baseband integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing device, or network device.

[0278] The various blocks illustrated in the accompanying drawings may represent steps in the method and / or code portions in the computer program 406. The description of a particular order of blocks does not necessarily mean that the blocks have a required or preferred order, and the order and arrangement of the blocks may vary. In addition, some blocks may be omitted.

[0279] If a structural feature has been described, it may be replaced by a component that performs the function or functions of the structural feature, whether the function or functions are explicitly or implicitly described.

[0280] As used herein, a "module" refers to a unit or device that does not include certain parts / components added by the final manufacturer or user. For example, user device 110 may be a module.

[0281] The above examples can be used as enabling components for the following systems:

[0282] Automotive systems; telecommunications systems; electronic systems, including consumer electronics; distributed computing systems; media systems for generating or presenting media content, including audio, video, and audiovisual content, and mixed reality, mediated reality, virtual reality, and / or augmented reality; personal systems, including personal health systems, or personal fitness systems; navigation systems; user interfaces, also known as human-machine interfaces; networks, including cellular, non-cellular, and fiber-optic networks; ad hoc networks; the Internet; the Internet of Things; virtualized networks; and related software and services.

[0283] According to examples of the present disclosure, the device may be provided in an electronic device (e.g., a mobile terminal). However, it should be understood that the mobile terminal is only an example of an electronic device that will benefit from the examples of implementation of the present disclosure, and therefore should not be considered to limit the scope of the present disclosure to this. Although in some implementation examples, the device may be provided in a mobile terminal, other types of electronic devices, such as but not limited to: mobile communication devices, handheld portable electronic devices, wearable computing devices, portable digital assistants (PDAs), pagers, mobile computers, desktop computers, televisions, gaming devices, laptops, cameras, video recorders, GPS devices, and other types of electronic systems, can easily adopt examples of the present disclosure. In addition, whether or not the device is intended to provide mobility, they can easily adopt examples of the present disclosure.

[0284] The term "comprising" is used in this document in an inclusive rather than exclusive sense. That is, any reference to X including Y indicates that X may include only one Y or more than one Y. If "comprising" is intended to be used in an exclusive sense, it will be made clear in the context by referring to "including only one..." or using "consisting of..."

[0285] In this specification, the terms "connected", "coupled" and "in communication" and their derivatives mean operationally connected / coupled / in communication. It should be understood that any number or combination of intermediate components (including no intermediate components) may be present, i.e., to provide direct or indirect connection / coupling / in communication. Any such intermediate components may include hardware and / or software components.

[0286] As used herein, the term "determining" (and grammatical variations thereof) may include, but are not limited to: calculating, computing, processing, deriving, measuring, investigating, identifying, searching (e.g., searching in a table, database, or other data structure), ascertaining, etc. Furthermore, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), obtaining, etc. Furthermore, "determining" may include resolving, selecting, choosing, establishing, etc.

[0287] In this specification, reference is made to various examples. The description of features or functions associated with an example indicates that these features or functions are present in the example. Whether explicitly stated or not, the use of the term "example" or "for example" or "may" or "might" in the text indicates that these features or functions are at least present in the described example, whether or not described as an example, and they may but not necessarily be present in some or all other examples. Therefore, "example", "for example", "may" or "might" refers to a specific instance in a class of examples. The attributes of an instance may be attributes of only that instance, or may be attributes of the class, or may be attributes of a subclass of the class, which includes some but not all instances in the class. Therefore, it is implicitly disclosed that features described with reference to one example rather than with reference to another example may be used in the other example as part of a working combination where possible, but do not necessarily have to be used in the other example.

[0288] Although the preceding paragraphs have described the examples with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the claims.

[0289] Features described in the preceding description may be used in combinations other than the combinations explicitly described above.

[0290] Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

[0291] Although features have been described with reference to certain examples, those features may also be present in other examples whether described or not.

[0292] The terms "a", "an" or "the" are used in this document in an inclusive, rather than exclusive, sense. That is, any reference to X including a / an / the Y indicates that X may include only one Y or more than one Y, unless the context clearly indicates otherwise. If the exclusive meaning of "a", "an" or "the" is intended, it will be clearly stated in the context. In some cases, the use of "at least one" or "one or more" may be used to emphasize the inclusive meaning, but the absence of these terms should not be regarded as inferring any exclusive meaning.

[0293] The presence of a feature (or combination of features) in a claim refers to the feature or (combination of features) itself, and also refers to features that achieve substantially the same technical effect (equivalent features). Equivalent features include, for example, features that are variants 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.

[0294] In this specification, various examples have been cited that use adjectives or adjective phrases to describe example characteristics. Such descriptions of characteristics associated with examples indicate that the characteristics exist in some examples exactly as described, and in other examples substantially as described.

[0295] The above description describes some examples of the present disclosure, but those skilled in the art will be aware of possible alternative structures and method features that provide equivalent functionality to the specific examples of such structures and features described above, and have been omitted from the above description for the sake of brevity and clarity. Nevertheless, the above description should be understood to implicitly include references to such alternative structures and method features that provide equivalent functionality, unless such alternative structures or method features are explicitly excluded in the above description of examples of the present disclosure.

[0296] While an effort has been made in the foregoing description to draw attention to those features regarded as important, it should be understood that the applicant may seek protection by way of claims for any patentable feature or combination of features mentioned above and / or shown in the drawings, whether or not emphasis has been placed thereon.

Claims

1. A user equipment comprising components for: before decoding the received cell change configuration, decoding and applying the received cell change measurement configuration, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover, and The cell change configuration provides cell parameters that enable the handover.

2. The user equipment according to claim 1, comprising means for: decoding the received cell change measurement configuration; performing the measurement according to the received cell change measurement configuration; and The received cell change configuration is decoded depending on the measurements.

3. The user equipment according to claim 1 or 2, comprising means for: Determining to initiate the handover with the candidate cell; Based on the determination, the received cell change configuration for the candidate cell is decoded.

4. A user equipment according to any preceding claim, comprising means for: Depending on the measurements performed, a low layer triggered mobility LTM measurement report is sent to the network.

5. A user equipment according to any preceding claim, comprising means for: Acknowledging decoding of the received cell change measurement configuration to a network, and / or acknowledging decoding of the received cell change configuration to the network.

6. A user equipment according to any preceding claim, comprising means for: A first message including the cell change measurement configuration and a second message including the cell change configuration are received from a network.

7. The user equipment according to claim 6, comprising means for: decoding the received cell change measurement configuration; performing the measurement according to a measurement configuration changed by the cell; receiving the second message including the cell change handover configuration; and The received cell change configuration is decoded.

8. The user equipment according to claim 6 or 7, wherein the second message comprises the cell change configuration for one or more cells for which the user equipment has performed measurements.

9. The user equipment according to claim 7 or 8, comprising means for: The first message is decoded upon receipt, and / or the second message is decoded upon receipt.

10. A user equipment according to any preceding claim, comprising means for receiving a message from a network, the message comprising the cell change measurement configuration and the cell change configuration.

11. The user equipment of claim 10, wherein the message comprises layer 3 radio resource control (RRC) information.

12. The user equipment according to claim 10 or 11, comprising means for using measurements made according to the cell change measurement configuration for a UE triggered cell change.

13. The user equipment according to any one of claims 10 to 12, wherein the message comprises: A data structure, the data structure comprising: a first information element comprising the cell change measurement configuration, wherein the cell change measurement configuration provides parameters specifying the measurements to be performed for managing the handover; and a plurality of second information elements, wherein each second information element of the plurality of second information elements comprises the cell change configuration for one of a plurality of candidate cells, and wherein the cell change configuration provides parameters for enabling the handover with the one of the plurality of candidate cells.

14. A method for communication, comprising: before decoding the received cell change configuration, decoding and applying the received cell change measurement configuration, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover, and The cell change configuration provides cell parameters that enable the handover.

15. A computer program which, when executed by one or more processors, causes: before decoding the received cell change configuration, decoding and applying the received cell change measurement configuration, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover, and The cell change configuration provides cell parameters that enable the handover.

16. A network node comprising means for: sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover; A cell change configuration is separately sent to the user equipment, wherein the cell change configuration provides cell parameters enabling the handover.

17. The network node according to claim 16, configured to send a first message including the cell change measurement configuration, and separately send a second message including the cell change configuration.

18. The network node according to claim 16 or 17, configured to selectively send a cell change configuration to the user equipment in response to receiving a measurement report identifying a cell for managing handover from the user equipment, the cell change configuration being used to enable a cell change to the identified cell, or The method is configured to selectively send a cell change configuration to the user equipment in response to receiving a measurement report identifying a subset of cells for managing handover from the user equipment, the cell change configuration being used to enable a cell change to each cell in the identified subset of cells.

19. A network node according to any one of claims 16 to 18, wherein the network node is configured to receive a message comprising a cell change configuration and the cell change measurement configuration for a plurality of cells; and is configured to send the received cell change measurement configuration to the user equipment instead of the received cell change configuration; and is configured to selectively send a cell change configuration to the user equipment, the cell change configuration being used to enable a cell change to a subset of cells.

20. The network node according to claim 19 is configured to selectively send a cell change configuration to the user equipment in response to receiving a measurement report for managing handover identifying a subset of the plurality of cells from the user equipment, the cell change configuration being used to enable a cell change to each cell in the identified subset of cells.

21. The network node according to any one of claims 17 to 20, wherein the received message comprises a data structure, the data structure comprising: a first information element, the first information element comprising the cell change measurement configuration, wherein the cell change measurement configuration provides parameters specifying the measurements to be performed for managing the handover; as well as a plurality of second information elements, wherein each second information element of the plurality of second information elements comprises the cell change configuration for one of a plurality of candidate cells, and wherein the cell change configuration provides parameters for enabling the handover with the one of the plurality of candidate cells.

22. The network node according to any one of claims 17 to 21, wherein the received message includes mapping information, the mapping information including a one-to-one mapping for each cell change measurement configuration, the one-to-one mapping mapping the cell change measurement configuration to a cell identifier, thereby eliminating the need to decode the cell change measurement configuration.

23. The network node according to any one of claims 17 to 22, configured as a distributed unit.

24. A method for communication, comprising: sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover; as well as A cell change configuration is separately sent to the user equipment, wherein the cell change configuration provides cell parameters enabling the handover.

25. A computer program which, when executed by one or more processors of a network, causes: sending a cell change measurement configuration to a user equipment, wherein the cell change measurement configuration provides measurement parameters specifying measurements to be performed for managing the handover; and A cell change configuration is separately sent to the user equipment, wherein the cell change configuration provides cell parameters enabling the handover.

Images