Network node, method, and storage medium for mobility preparation enhancements

Abstract

In some example embodiments, a network node, method, and computer-readable storage medium for enhanced mobility preparation may be provided. The network node includes: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause means to send a handover request to at least one candidate node, receive a handover request confirmation from at least one candidate node, wherein the confirmation is based on excluding a Layer 1 reporting configuration for at least one candidate node from a handover process triggered by at least one candidate node that is based on a Layer 3 measured handover, and send a radio resource reconfiguration to another means, the reconfiguration excluding a Layer 1 reporting configuration for at least one candidate node.

Description

Technical Field

[0001] Various example embodiments relate to the field of wireless communications, and more specifically to enhancements for mobility preparation triggered by Layer 1 / Layer 2. Background Technology

[0002] In the field of wireless communications, there are multiple mobility management concepts, including mobility processes such as, for example, lower-layer triggered mobility (LTM) or layer 1 (L1) / layer 2 (L2) triggered mobility. These can include cell switching or handover processes, particularly where the serving cell of a device (e.g., a user equipment (UE)) can be changed or handed over, for example, by changing or handing over to a candidate cell or a target cell. Mobility processes (such as LTM) can include two rounds of processes during the mobility preparation phase, in which one or more candidate nodes are prepared for mobility, one for reserving cell resources and retrieving information, and the other for updating merging information. This can be beneficial, for example, by optimizing the processing of updating merging information to reduce and / or minimize overhead and / or energy consumption, such as saving energy for the device (e.g., the UE), and / or reducing the overhead between gNBs involved in L1 / L2 LTM. Summary of the Invention

[0003] The subject matter of the independent claims is provided for several aspects. Further aspects, advantages, and / or features are defined in the dependent claims, the description, and / or the drawings.

[0004] In the first example, a network node may be provided, including: At least one processor; and At least one memory storing instructions, which, when executed by at least one processor, cause the device to: send a handover request to at least one candidate node, wherein the handover request includes: an indication that a common resource configuration will be used by the at least one candidate node; receiving a handover request confirmation from the at least one candidate node, wherein the confirmation includes a report configuration indicating that the common resource configuration is being used; and sending a radio resource reconfiguration to the device, the reconfiguration including a report configuration indicating that the common resource configuration is being used.

[0005] Furthermore, according to the first example aspect, a network node can be provided, including components for the following: Send a handover request to at least one candidate node, wherein the handover request includes: an indication that a public resource configuration will be used by at least one candidate node; Receive a handover request confirmation from at least one candidate node, wherein the confirmation includes: a report configuration indicating that a public resource configuration is being used, and Send a radio resource reconfiguration to the device, the reconfiguration including a report configuration indicating that a public resource configuration is being used.

[0006] In the second example, a method can be provided, including: Send a handover request to at least one candidate node, wherein the handover request includes: an indication that a public resource configuration will be used by at least one candidate node; Receive a handover request confirmation from at least one candidate node, wherein the confirmation includes: a report configuration indicating that a public resource configuration is being used, and Send a radio resource reconfiguration to the device, the reconfiguration including a report configuration indicating that a public resource configuration is being used.

[0007] In a third example aspect, a non-transitory computer-readable storage medium may be provided, including program instructions that, when executed by a device, particularly any device according to the first example aspect and / or the associated example embodiments described herein, cause operation including: sending a handover request to at least one candidate node, wherein the handover request includes an indication that a common resource configuration will be used by at least one candidate node; the confirmation includes a reporting configuration indicating that the common resource configuration is used; and sending a radio resource reconfiguration to the device, the reconfiguration including a reporting configuration indicating that the common resource configuration is used.

[0008] In the fourth example aspect, it can be combined with any of the example aspects and / or any of the associated example embodiments described herein to provide a network node comprising: At least one processor; and At least one memory storing instructions that, when executed by at least one processor, cause the device to at least: Send a handover request to at least one candidate node. At least one candidate node receives a handover request confirmation, wherein the confirmation is based on the exclusion of the Layer 1 reporting configuration for the at least one candidate node from the handover process triggered by the at least one candidate node, which is based on a Layer 3 measurement handover, and sends a radio resource reconfiguration to another device, the reconfiguration excluding the Layer 1 reporting configuration for the at least one candidate node.

[0009] According to the fourth example aspect, a network node can be provided, including components for the following: Send a handover request to at least one candidate node. Receive handover request confirmation from at least one candidate node, wherein the confirmation is based on the exclusion of Layer 1 reporting configurations for at least one candidate node from a handover process triggered by at least one candidate node, which is based on a Layer 3 measurement handover. Radio resource reconfiguration is sent to another device, the reconfiguration excluding Layer 1 report configurations for at least one candidate node.

[0010] In the fifth example, one approach could be provided, including: Send a handover request to at least one candidate node. Receive handover request confirmation from at least one candidate node, wherein the confirmation is based on the exclusion of Layer 1 reporting configurations for at least one candidate node from a handover process triggered by at least one candidate node, which is based on a Layer 3 measurement handover. Radio resource reconfiguration is sent to another device, the reconfiguration excluding Layer 1 report configurations for at least one candidate node.

[0011] In a sixth example aspect, a non-transitory computer-readable storage medium may be provided, including program instructions that, when executed by a network node, particularly a network node according to any of the associated example embodiments described herein, cause operation including: sending a handover request to at least one candidate node. Receive handover request confirmation from at least one candidate node, wherein the confirmation is based on the exclusion of Layer 1 reporting configurations for at least one candidate node from a handover process triggered by at least one candidate node, which is based on a Layer 3 measurement handover. Radio resource reconfiguration is sent to another device, the reconfiguration excluding Layer 1 report configurations for at least one candidate node.

[0012] In the seventh example aspect, it can be combined with any of the example aspects and / or any of the associated example embodiments described herein to provide a network node comprising: At least one processor; and At least one memory storing instructions, wherein the instructions, when executed by at least one processor, cause the device to at least Send a handover request to at least one candidate node in the candidate node group. Receive handover request confirmation from at least one candidate node, wherein the confirmation includes the following indications: that no further mobility procedure will be triggered by the network node based on mobility within the cell of at least one candidate node or within the cell of the candidate node group, and send radio resource reconfiguration to the user equipment.

[0013] According to the seventh example aspect, a network node may be provided, including components for the following: Send a handover request to at least one candidate node in the candidate node group. Receive handover request confirmation from at least one candidate node, wherein the confirmation includes the following indications: that no further mobility procedure will be triggered by the network node based on mobility within the cell of at least one candidate node or within the cell of the candidate node group, and send radio resource reconfiguration to the user equipment.

[0014] In the eighth example aspect, there may be a method that includes: Send a handover request to at least one candidate node in the candidate node group. At least one candidate node receives a handover request confirmation, wherein the confirmation includes the following indications: based on mobility, no further mobility procedures will be triggered by the network node within the cell of at least one candidate node or within the cell of the candidate node group, and a radio resource reconfiguration is sent to the user equipment.

[0015] In the ninth example aspect, a non-transitory computer-readable storage medium may be provided, including program instructions that, when executed by a network node, particularly a network node according to the seventh example aspect and / or any of the associated example embodiments described herein, cause operation including: Send a handover request to at least one candidate node in the candidate node group. Receive handover request confirmation from at least one candidate node, wherein the confirmation includes the following indications: that no further mobility procedure will be triggered by the network node based on mobility within the cell of at least one candidate node or within the cell of the candidate node group, and send radio resource reconfiguration to the user equipment. Attached Figure Description

[0016] Some exemplary embodiments will now be described with reference to the accompanying drawings.

[0017] The complete disclosure that is readily available and achievable by one of ordinary skill in the art is set forth in more detail in the remainder of the specification, including reference to the accompanying drawings:

[0018] Figure 1 An example of a wireless communication network is shown;

[0019] Figure 2 Example signaling diagrams based on the topics described in this article are shown;

[0020] Figure 3 Example signaling diagrams based on the topics described in this article are shown;

[0021] Figure 4 Example signaling diagrams based on the topics described in this article are shown;

[0022] Figure 5Example signaling diagrams based on the topics described in this article are shown;

[0023] Figure 6 A flowchart illustrating an example aspect of the topic described in this article is shown;

[0024] Figure 7 A flowchart illustrating an example aspect of the topic described in this article is shown;

[0025] Figure 8 A flowchart illustrating an example aspect of the topic described in this article is shown;

[0026] Figure 9 An example of the device is shown. Detailed Implementation

[0027] Referring now to various embodiments, one or more examples of these embodiments are illustrated in the accompanying drawings. In the following description of the drawings, the same reference numerals may refer to the same components. Generally, only differences with respect to the various embodiments may be described. Each embodiment is provided by way of interpretation, but is not intended to be limiting. Furthermore, features illustrated or described as part of one embodiment may be used on or in combination with other embodiments to produce further embodiments. This specification is intended to include these modifications and variations.

[0028] The accompanying drawings are schematic diagrams not drawn to scale. Some elements in the drawings may have exaggerated dimensions for the purpose of highlighting aspects of this disclosure and / or for clarity of presentation.

[0029] For mobility purposes, such as for mobility procedures and / or carrier aggregation, one or more measurements may be configured for a device (e.g., a user equipment (UE)), particularly when connected to at least one cell. A “mobility procedure” can be considered or can refer to the process of switching, handing over, or changing a device (particularly a UE) from one network entity (e.g., a cell, beam, transmit / receive point, or access point) to another network entity, particularly the process of maintaining seamless connectivity. Mobility ensures communication when a user moves across different coverage areas. It can prevent dropped calls and / or interruptions in data sessions. Multiple mobility procedures may also be referred to as multiple cell switching / handover / change procedures. Non-limiting examples of mobility procedures are handovers (HOs) that may occur in multiple higher layers (e.g., Layer 3 (L3)), and / or cell switches or cell changes that may occur in lower layers (e.g., Layer 1 (L1) / Layer 2 (L2)). "Lower-layer triggered mobility" (LTM) or "Layer 1 (L1) / Layer 2 (L2) triggered mobility" can refer to a specific mobility procedure, such as a mobility procedure initiated in a cellular network based on events and / or measurements detected at lower layers of the protocol stack (e.g., the physical layer or Layer 1 and / or the data link layer or Layer 2 or MAC layer, etc.). LTM can provide mechanisms, for example, for network nodes and UEs, to address mobility needs, complementing mobility procedures at higher layers (e.g., Layer 3 or Radio Resource Control (RRC)). LTM can include cell change / handover procedures, where the UE's serving cell (e.g., primary cell (PCell), PSCell, or secondary cell (SCell)) can be changed / handed over (e.g., by a network node) for example, by sending a message (e.g., a cell change / handover command or an LTM cell change / handover command). It can be assumed that the LTM cell change / handover command will be delivered via Media Access Control (MAC) signaling, particularly using a MAC Control Element (CE). Therefore, not using RRC signaling as an L3-based handover can be a method for changing between cells.

[0030] "Mobility or cell configuration" (these terms may be used interchangeably herein) can be considered as a set of network parameters, such as a set of network parameters provided to a device (e.g., a UE) to guide how it should perform (multiple) mobility procedures and / or define how and / or when the device (e.g., a UE) triggers one or more mobility-related actions. Mobility configuration can be associated with at least one candidate / target cell or candidate node or candidate gNB. Mobility configuration can include at least one of the following: at least one Channel State Information (CSI), resource configuration, and / or at least one CSI reporting configuration. Mobility configuration can also include at least one offset value. In the example, mobility configuration can be an L1 / L2 triggered mobility LTM configuration or an LTM (candidate) cell configuration. In the exemplary context of LTM, mobility configuration can be included in a message. This can be referred to, for example, as an "LTM configuration message," which can be understood as, for example, at least one message from a network node to configure a device (e.g., a user equipment (UE)) for one or more parts or steps of the LTM process and / or LTM procedures (e.g., LTM cell change / handover). LTM messages may include data, information, configuration, parameters, and / or instructions, particularly as exemplarily outlined above, for example for a UE, such as to perform and / or trigger mobility-related measurements and / or reports.

[0031] Mobility processes, such as those exemplified above, may have multiple associated measurements and / or multiple reports, and mobility is subsequently triggered, particularly based on such multiple measurements and / or reports. These measurements may include, for example, multiple cell measurements and / or reports.

[0032] In the context of LTM, a non-limiting example of a measurement for at least one cell can be a Layer 1 (L1) measurement. Multiple L1 measurements may include multiple physical layer measurements to evaluate radio conditions. These measurements may involve, for example, using one or more beams to evaluate the signal strength, quality, and / or other parameters of multiple reference signals transmitted by network nodes. However, it should be noted that these may also be applied or applicable without the concept of using one or more beams. L1 measurements can be used for mobility management (such as handover / cell transitions, beam management, and / or connection re-establishment). For the selection of appropriate candidate cells and / or beams, such as for early uplink and / or downlink synchronization and / or cell handover in LTM, both intra-frequency L1 measurements and / or inter-frequency L1 measurements can be supported and / or utilized, for example using measurement reference signals (RS) such as synchronization signal blocks (SSBs) transmitted from candidate cells or channel state information reference signals (CSI-RS). LTM cell handover / change decisions can be based on measurements (e.g., L1 measurements, and / or L3 measurements) that may be performed and / or reported by the UE (e.g., via corresponding L1 measurement reports or L3 measurement reports). "Uplink (UL) synchronization" can refer to the process by which a device (e.g., a UE) aligns its transmission timing with the network's desired timing, for example, to ensure correct communication. In other words, the device (e.g., a UE) can transmit its signals at the correct timing, for example, so that they reach the network without collision or interference. "Downlink (DL) synchronization" can refer to the process by which a device (e.g., a UE) aligns itself with the timing and / or frequency of downlink signals from the network. DL synchronization can ensure that the device (e.g., a UE) can correctly receive and / or interpret signals from the network. "Early" synchronization can refer to initiating and / or performing at least one of the following: UL or DL ​​synchronization, particularly before the actual execution of the cell handover / change process. In-frequency L1 measurement can refer to a measurement performed on a reference signal transmitted, for example, on the same carrier frequency or the same active bandwidth portion (BWP) as the serving cell, which can be used, for example, to assess the signal quality of the serving cell or neighboring cells. Inter-frequency L1 measurements can refer to measurements performed on a reference signal transmitted at a frequency different from the serving cell's carrier frequency. These measurements can be used, for example, to assess the signal quality of cells or beams operating at different frequency layers (e.g., different carrier frequencies) or on a BWP different from the active BWP. Reference signals used for L1 measurements can include synchronization signal blocks (SSBs), multiple SSB-based signal or channel state information reference signals (CSI-RS), etc. A non-limiting example in the context of associated reporting / reporting in LTM can be layer 1 (L1) reporting / reporting. L1 reporting can be periodic (e.g., every "X" ms), semi-persistent, aperiodic, or event-based (e.g., when beam quality changes significantly), etc.L1 reporting can involve the physical channel on which / it is reported (i.e., the Physical Uplink Control Channel (PUCCH) or the Physical Uplink Shared Channel (PUSCH)). Similarly, L1 reporting can involve a container in which the report is sent (e.g., a UCI, MAC CE report, RRC measurement report, or CSI report container). When a device (e.g., a UE) detects a sufficiently strong L1 measurement, for example, from a neighboring cell, a report can be sent, for example, to trigger (multiple) L1 or L3 measurements. As the quality of different beams changes, L1 reports can be generated repeatedly and / or continuously.

[0033] In the context of LTM, a non-limiting example for using at least one cell measurement can be a Layer 3 (L3) measurement. Multiple L3 measurements can be used to provide higher-layer mobility management functions and / or can assist in determining whether a cell is a viable candidate for mobility, for example, by monitoring reference signals (RS) (such as SSB-based signals). For example, an L3 measurement can correspond to an L1 measurement that is filtered at Layer 3 in addition to an L1 filter (or filtered differently at Layer 1), for example, to remove or minimize the effects of the channel (e.g., fast fading), particularly to reduce short-term variations in the measurement results. An L3 measurement can correspond to the average of multiple beam measurements corresponding to a cell. A non-limiting example in the context of LTM for associated reporting / reporting can be a Layer 3 (L3) report / reporting.

[0034] A “candidate cell” (or “target cell” or “candidate node”) (these terms are used interchangeably herein) can refer to a serving cell among neighboring cells or the UE’s current serving cell (e.g., SCell), which the device (e.g., the UE) evaluates, particularly during mobility events, as a potential replacement for the current serving cell (e.g., PCell or PSCell). The UE can initiate or assist the network in initiating a transition / handover / change process to the target cell if certain conditions are met. A “serving cell” or “source node” or “source gNB” can be an active cell currently providing network connectivity to or serving the device (e.g., the UE). In the non-restrictive context of LTM, (multiple) candidate cells or candidate nodes can be (multiple) neighboring cells or nodes or gNBs or the UE’s current serving cell (e.g., SCell) (as mentioned above). In a non-limiting example of 5G, the term "cell" can and / or may be applied as follows: i) primary cell (PCell), ii) secondary cell (SCell), iii) primary cell of a secondary cell group (PSCell), iv) special cell (SpCell), which can be specifically used to collectively refer to PCell or PSCell. There may be only one special cell for each cell group. A PCell can specifically be the primary cell in / for the primary cell group (MCG), and a PSCell can specifically be the primary cell in / for the secondary cell group (SCG). Each cell group can have multiple SCells, but only one PCell. All cell types can be configured for target or candidate cells. A target cell can be the cell from which a device (e.g., UE) is performing a handover or cell change. A serving cell can be, in particular, the cell currently serving the device (e.g., UE). A source cell can be the cell from which a device (e.g., UE) is performing a handover or cell change. A candidate cell or candidate node can be a candidate cell that becomes the target cell for a handover or cell change.

[0035] A "measurement configuration" (which may also be referred to as a measurement and / or reporting configuration) can refer to a set of parameters and / or rules that define how a device (e.g., a UE) can perform, implement, and / or execute one or more measurements. The measurement configuration can be provided by the network and / or specify which frequency to measure, what signal (e.g., a reference signal) to measure, and / or how often / how frequently the measurements should be performed and / or under what conditions they should be reported back to the network. The measurement configuration may include at least one "measurement object," which can specify and / or define the object, element, signal, carrier frequency, cell, entity, measurement window, resource block, and / or channel to be measured, particularly what the UE should measure, such as, for example, at least one signal (e.g., Channel State Information (CSI) Reference Signal (RS)), Synchronization Signal Block (SSB), SSB-based synchronization signal, etc. The measurement configuration may define and / or include a measurement period (e.g., SMTC (SSB-based Measurement Timing Configuration)), such as the frequency at which the measurement will be performed. Providing the measurement configuration to a device (e.g., a UE) can be referred to as "configuring" the device (e.g., the UE) or the device (e.g., the UE) being "configured." It should be noted that measurement configurations can also be included in cell change commands. In particular, cell change commands such as handover commands or handover requests (e.g., RRC) can include at least one measurement configuration for at least one or more cells. The device (e.g., UE) can optionally store all source measurements in the target measurement configuration (e.g., a cell change command with a measurement configuration can be used as an implicit indication to continue measurement).

[0036] For Layer 1 based measurements and reporting, a UE can be configured with one or more LTM CSI reporting configurations (e.g., LTM-CSI-ReportConfig), where each reporting configuration contains an LTM CSI resource configuration (LTM-CSI-ResourceConfig) that contains information about the resources to be used for channel measurements (L1-RSRP measurements). The LTM resource configuration may contain SSBs or CSI-RS from one or more candidate cells. For SSB-based measurements, for each reporting configuration, the UE can be configured to report M beams from each of the L configured candidate cells. That is, each LTM CSI resource setting (LTM-CSI-ResourceConfig) can contain the configuration of an LTM-CSI-SSB-ResourceSet, which includes a list of Z ≥ 1 SS / PBCH (SSB) block indices (given by ltm-CSI-SSB-ResourceList) and a list of Z LTM-CandidateIds (given by ltm-CandidateIDList), which refer to the candidate cells associated with the SS / PBCH block indices.

[0037] For each candidate cell, the UE determines the temporal behavior of the SSB block resources based on ssb-Periodicity and ssb-PositionsInBurst, and the frequency behavior of the SS / PBCH block resources is determined by the higher-layer parameters subCarrierSpacing and ssbFrequency.

[0038] For each cell, the LTM CSI report configuration is provided under the configuration of the currently serving cell, where each report configuration contains an indication of the LTM CSI resource configuration and other parameters related to the report (such as the timing of report transmission and uplink resources). The LTM CSI resource configuration may contain a set of SSB indexes from multiple candidate cells. This is placed in the common LTM configuration, i.e., LTM-Config. The detailed configuration of each SSB of the candidate cell is given in LTM-SSB-Config under LTM-CandidateIE, and these SSBs are indicated in the LTM CSI resource configuration. For each candidate cell, the LTM CandidateIE contains the configuration / information (such as SSB information for LTM measurements) required by the UE before cell handover.

[0039] The candidate cell configuration (e.g., LTM-candidate IE) also includes an RRC container (containing the candidate cell's RRCReconfiguration of the ServingCellConfig), which contains all the configuration details the UE will need after a cell handover from its current serving cell to this candidate cell. The reporting configuration for handover from this cell is provided in the candidate cell's RRC container. In other words, the ServingCellConfig given under LTM-candidate IE contains the configuration details required to perform regular serving cell operations within the candidate cell.

[0040] Figure 1 An example of a communication system to which the embodiments described herein can be applied is illustrated. The system may include a control node 110 providing one or more cells (such as cell 100) and a control node 112 providing one or more other cells (such as cell 102). For example, each cell may be, for example, a macro cell, micro cell, femtocell, or picocell, and may be considered to belong to the control node providing it. A cell may define the coverage area or service area of ​​a corresponding access node. Control nodes 110 and 112 may be, for example, an evolved Node B (eNB) in LTE and LTE-A, an ng-eNB in ​​eLTE, a gNB in ​​5G, or any other means capable of controlling radio communications and managing radio resources within a cell. Control nodes 110 and 112 may be referred to as a base station, network node, access node, or means.

[0041] The system can be a cellular communication system consisting of a radio access network of access nodes, with each access node controlling one or more corresponding cells. Access node 110 can provide user equipment (UE) 120 (one or more UEs) with radio access to other networks, such as the Internet. Radio access can include downlink (DL) communication from the control node to UE 120 and uplink (UL) communication from UE 120 to the control node.

[0042] Additionally, although not shown, one or more local access nodes may be arranged such that the cell provided by the local access node at least partially overlaps with the cell of access nodes 110 and / or 112. The local access node may provide radio access within a sub-cell. Examples of sub-cells may include microcells, picocells, and / or femtocells. Typically, a sub-cell provides a hotspot within a macrocell. The operation of the local access node may be controlled by an access node, under which the sub-cell is provided within the control area of ​​that access node. Typically, the control node for a small cell may also be referred to as a base station, network node, or access node.

[0043] Multiple UEs 120 and 122 can exist in the system. Each of them can be served by the same or different control nodes 110 and 112. With a D2D communication interface established between UEs 120 and 122, UEs 120 and 122 can communicate with each other.

[0044] The term "terminal device" or "UE" refers to any terminal device capable of wireless communication. By way of example and not limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), access terminal (AT), or apparatus. The terminal device may include, but is not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices (such as digital cameras), gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop-mounted devices (LMEs), USB dongles, smart devices, wireless client devices (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in industrial and / or automated processing chain environments), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," "device," and "UE" are used interchangeably.

[0045] Based on the topics described herein and mentioned above, the L1 / 2 triggered mobility framework involves a two-round process in most cases. In the first round, which can be viewed as a cell resource reservation process, the source gNB requests inter-gNB LTM for one or more candidate cells belonging to one or more candidate gNBs or candidate nodes. The source gNB initiates a handover request message for each candidate cell, containing a candidate cell ID and CSI resource configuration (including SSB information, since SSBs are typically cell-specific RSs, and the source gNB may already have SSB information for all candidate cells collected during the F1 / Xn setup process; however, for CSI-RSs, since such RSs are UE-specific RSs, this information is collected by the handover request and response messages) for subsequent LTM. The source gNB may request CSI-RS configuration from (multiple) candidate gNBs. Admission control can then be performed by the candidate gNBs or candidate nodes. This first round can also be viewed as the LTM preparation phase.

[0046] Following admission control, candidate nodes (multiple gNBs) prepare multiple LTM configurations and send an inter-gNB response (HO request confirmation) to the source gNB, including the generated RRC configuration for the accepted candidate cell. The candidate gNBs may also include CSI-RS configuration upon request.

[0047] Intra-gNB LTM refers to mobility restricted to cells belonging to the same gNB. Inter-gNB LTM refers to mobility restricted to cells belonging to different gNBs, where the different gNBs belong to the same central cell (CU).

[0048] In the second process of the mobility framework triggered by L1 / 2, which can be considered an information update process, the source gNB sends an LTM configuration update to (multiple) candidate gNBs to update the LTM configuration of (multiple) candidate cells. The source gNB may include a public CSI-RS resource configuration. (Multiple) candidate gNBs send an LTM configuration update confirmation message to the source gNB. (Multiple) candidate gNBs may also provide a CSI-RS report configuration that can be used later for subsequent handover when the UE moves to one of the cells of (multiple) candidate gNBs. This process defines the process by which the source gNB sends LTM configuration updates to the UE. RRCReconfiguration information.

[0049] The inter-CU LTM preparation phase includes the two steps mentioned above (handover request and handover response, primarily used to collect configuration information for CSI-RS used in Layer 1 measurements and reporting). Compared to traditional handover and conditional handover scenarios, this increases the total number of signaling messages required to complete the preparation. The two-step signaling can also introduce additional latency when delivering LTM configuration messages to the UE. Depending on the number of candidate gNBs involved, the signaling overhead for individual UE LTM preparation can increase accordingly. Therefore, reducing the preparation time for UE LTM occurring between CUs is beneficial and desirable.

[0050] Figure 2 An example signaling diagram based on the topics described herein is shown. It can be assumed that UE 120 sends measurements containing neighboring cells to source gNB 110. Measurement ReportMessage (L3 Measurement Results). The source gNB 110 can be a network node or a candidate node. In step 202, the source gNB 110 decides to configure inter-gNB LTM. In steps 204 and 206, the source gNB initiates and sends a handover request message for each candidate cell or candidate node, which can belong to the target gNB 111 and other gNBs 112. A candidate node can be at least one candidate node, multiple candidate nodes, or one of other candidate nodes. The handover request may include a candidate cell ID, a CSI resource configuration for subsequent LTM (if any, for SSB-based CSI resource configuration), and a request to provide CSI-RS information. Furthermore, the handover request may include the following indication: a common resource configuration, a common measurement set, or a common CSI resource configuration (containing CSI-RS from all configured candidates) will be used by the target gNB 111 and other gNBs 112 for subsequent LTM. The handover request is for lower-layer triggered mobility. In other words, the handover request indicates that there are no multiple CSI resource configurations for Layer 1 measurements and reporting. For LTM or conditional LTM, this indication can be sent within the LTM information request information element of the switch request message.

[0051] This indication can be a parameter used to specify whether a public or single LTM-CSI-RS resource configuration is used. This parameter can be referred to as "Fixed-LTM-Report-Config" or "Single-CSI-Resource-Config" and can be set to true, false, 0, or 1. The public resource configuration is used for lower-tier triggered mobility measurements or for Layer 1 measurements. Furthermore, the reporting configuration is either a Layer 1 reporting configuration or a lower-tier triggered mobility reporting configuration.

[0052] In steps 208 and 210, candidate nodes (multiple target and other gNBs) 111 and 112 prepare multiple LTM configurations and send an inter-gNB response (Handover Request Acknowledgment ACK) to the source gNB 110. The Handover Request ACK, or for both LTM and CLTM, includes an LTM information response element in the Handover Request Acknowledgment that indicates the use of a report configuration or CSI report configuration. Since only one common CSI resource configuration exists, all CSI report configurations need to use / associate with this common CSI resource configuration; that is, no additional steps are required, such as collecting candidate cell report configurations by sharing the prepared CSI resource configurations, at least for the current handover or handover in the current source cell. The information of the finally prepared CSI resource configuration can be shared with the candidate nodes later, but there is no need to delay the current handover by delaying the delivery of RRC Reconfiguration to the UE. The report configuration can be included in the Radio Resource Control (RRC) reconfiguration. More specifically, when a public or individual LTM-CSI-RS resource configuration is indicated, the candidate node includes an LTM-Report-config corresponding to LTM-CSI-resource-ID=1 when preparing its RRC reconfiguration. This indication allows the receiving node to know that the same LTM configuration will be applied to subsequent LTM mobility.

[0053] In step 212, the source gNB 110 forwards the RRC reconfiguration to the UE 120, and the UE 120 stores the LTM candidate configuration and sends it to the source gNB. RRCReconfigurationComplete Message 214. RRC reconfiguration includes a report configuration indicating that public resource configurations are being used.

[0054] Figure 3 An example signaling diagram based on the topics described herein is shown. It can be assumed that UE 120 sends measurements containing neighboring cells to source gNB 110. Measurement Report Message (L3 measurement results). In 302, the source gNB 110 decides to configure inter-gNB LTM. In 304 and 306, the source gNB initiates a handover message for each candidate cell or candidate node. Each candidate cell or candidate node can belong to the target gNB 111 and other gNBs 112. The handover request may include a candidate cell ID, CSI resource configuration for subsequent LTM (if any, for SSB-based CSI resource configuration), and a request to provide CSI-RS information.

[0055] In steps 310 and 312, candidate nodes (multiple target and other gNBs) 111 and 112 prepare multiple LTM configurations and send an inter-gNB response (handover request acknowledgment ACK) to the source gNB 110. If the candidate node does not support the Layer 1 measurement-based cell handover procedure for cell handover from the candidate node (or when the UE is served by the candidate node), the handover request ACK does not include or does not include reporting configuration, Layer 1 reporting configuration, or CSI reporting configuration. In this case, the handover in the candidate node can be considered a Layer 3 measurement-based handover, or the candidate node only supports Layer 3 measurement-based handover, so there is no need to prepare and provide Layer 1 reporting configurations, as these will not be used / supported. If the candidate node does not support Layer 1 reporting configurations, no additional steps are required, such as collecting the candidate cell's reporting configuration by sharing the prepared CSI resource configuration, at least for the current handover or the handover in the current source cell. The information of the finally prepared CSI resource configuration can be shared with the candidate node later, but there is no need to delay the current handover by delaying the delivery of RRCReconfiguration to the UE. Exclusion of the report configuration can be indicated by parameters or elements, such as the "No-LTM-Report-Config" element, which can be set to true or false or 0 or 1. Furthermore, in 314, the source gNB 110 sends a radio resource reconfiguration to UE 120 without or excluding the report configuration. The transmission of the radio resource reconfiguration in 314 can be conditionally performed based on whether all nodes among the candidate nodes or multiple candidate nodes indicate that the report configuration is excluded. More specifically, if all candidate nodes indicate that the report configuration is excluded, no radio resource reconfiguration is sent to UE 120. If UE 120 has already received the radio resource reconfiguration in 314, then in 316, UE 120 responds to the source gNB with an RRC reconfiguration completion message. Such an indication can be sent if no report configuration can be sent for LTM and CLTM in the LTM information response information element of the handover request confirmation.

[0056] Figure 4 An example signaling diagram based on the topics described herein is shown. The process is related to... Figure 3The description is the same up to and including steps 408 and 410. In 408 and 410, candidate nodes ((multiple) target and other gNBs) 111 and 112 prepare (multiple) LTM configurations and send an inter-NB response (handover request confirmation ACK) to the source gNB 110. This confirmation includes the following indication: based on mobility, no additional mobility procedures will be triggered by the network node within the cell of at least one candidate node. In other words, it indicates to the source gNB that the candidate node will not configure or perform subsequent inter-CU cell handovers, for example, inter-CU LTM after moving to one of its cells. This indication can be indicated by parameters or elements, such as the "no-subsequent-Inter-CU-LTM" element which can be set to true or false or 0 or 1. This indication can be sent if no reported configuration can be sent for LTM and CLTM in the LTM information response information element of the handover request confirmation. This indication indicates that the candidate node has prepared a candidate configuration that does not require LTM mobility outside the CU. For example, the report configuration does not need to include measurements from any cells outside the CU, and therefore does not need to receive updated / finalized CSI resource configuration information from the source CU. Therefore, the source gNB will not trigger further LTM configuration updates for these candidate nodes based on this indication. In other words, the source gNB does not send LTM configuration update messages to (multiple) candidate gNBs to update the LTM configuration of (multiple) candidate cells, thereby reducing signaling exchange. Furthermore, in 412, source gNB 110 sends a radio resource reconfiguration to UE 120, and in 414, source gNB 110 responds to the source gNB with an RRC reconfiguration completion message.

[0057] Figure 5 An example signaling diagram based on the topics described herein is shown. The process is related to... Figure 4The description is the same up to and including steps 508 and 510. In 508 and 510, candidate nodes ((multiple) target and other gNBs) 111 and 112 prepare (multiple) LTM configurations and send an inter-NB response (handover request confirmation ACK) to the source gNB 110. This confirmation includes the following indication: based on mobility within or only within cells belonging to the candidate node group, no further mobility procedures will be triggered by the network node. In other words, it indicates to the source gNB that the candidate node will not configure or perform subsequent inter-CU cell handovers, for example, inter-CU LTM after moving to one of its cells. This indication can be indicated by parameters or elements, such as "gNB-only LTM mobility," and can be set to true or false or 0 or 1. This indication can be sent if no configuration for LTM and CLTM is reported and sent in the LTM information response information element of the handover request confirmation. An indication that no additional mobility procedure for mobility will be triggered by the network node can cause the network node to skip or not send lower-layer triggered mobility configuration updates to candidate nodes. Furthermore, this indication can indicate that the mobility procedure for mobility, or mobility itself, will be triggered in one or more cells belonging to a candidate node, other candidate nodes, or multiple candidate nodes. In an embodiment, this indication can specifically indicate that mobility will be triggered in at least one cell belonging to at least one candidate node. For example, the reporting configuration may not need to include measurements from any cells outside the CU, and therefore, it may not be necessary to receive updated / finalized CSI resource configuration information from the source CU. In this case, the network node can skip sending lower-layer triggered mobility configuration updates to at least one candidate node.

[0058] Figure 6 A flowchart 600 illustrating an example aspect of the subject matter described herein is shown. This flowchart may include steps of the apparatus, network node, gNB, method, and / or non-transitory computer-readable medium mentioned herein. Flowchart 600 may include step 610 of a network node sending a HO request to a candidate node, which may be at least one or more candidate nodes. The HO request switching includes an indication that a public resource configuration will be used by the candidate node. Flowchart 600 may also include step 620 of a network node receiving an HO request ACK from a candidate node, the HO request ACK including a reporting configuration indicating that a public resource configuration is being used. Flowchart 600 may also include step 630 of a network node sending a radio resource reconfiguration to an apparatus or user equipment, the radio resource reconfiguration including a reporting configuration indicating that a public resource configuration is being used.

[0059] Flowchart 600 may include or be combined with one or more additional steps associated with or in combination with some of the exemplary aspects and / or associated exemplary embodiments described herein.

[0060] Figure 7 A flowchart 700 illustrating an example aspect of the subject matter described herein is shown. This flowchart may include steps of apparatus, network nodes, gNBs, methods, and / or non-transitory computer-readable media as mentioned herein. Flowchart 700 may include step 710 of a network node sending a HO request to a candidate node, which may be at least one or more candidate nodes. Flowchart 700 may also include step 720 of a network node receiving an HO request ACK from a candidate node, the HO request ACK being configured to exclude handover based on Layer 3 measurement handover. Flowchart 700 may also include step 730 of a network node sending a radio resource reconfiguration to an apparatus, which may be a user equipment, to exclude handover from reporting the reconfiguration.

[0061] Flowchart 700 may include or be combined with one or more additional steps associated with or in combination with some of the example aspects and / or related example embodiments described herein.

[0062] Figure 8 A flowchart 800 illustrating an example aspect of the subject matter described herein is shown. This flowchart may include steps of apparatus, network nodes, gNBs, methods, and / or non-transitory computer-readable media as mentioned herein. Flowchart 800 may include step 810 of a network node sending a HO request to candidate nodes, which may be at least one or more candidate nodes. Flowchart 800 may also include step 820 of a network node receiving an HO request ACK from a candidate node, the HO request ACK indicating that no further mobility procedures for mobility will be triggered by the network node if mobility is within the cell of the candidate node or within a group of candidate nodes that may belong to the same central cell (CU). Flowchart 800 may also include step 830 of a network node sending a radio resource reconfiguration to an apparatus, which may be a user equipment.

[0063] Flowchart 800 may include or be combined with one or more additional steps associated with or in combination with some of the exemplary aspects and / or associated exemplary embodiments described herein.

[0064] Figure 9An example of apparatus 50 according to an embodiment is illustrated. Apparatus 50 may be an element in or associated with a communication network. It may take the form of a user equipment (UE), mobile device (ME), mobile station, mobile device, fixed device, IoT device, or other type of device. As described herein, the apparatus may alternatively be referred to as, for example, a user equipment, mobile station, mobile device, mobile unit, mobile device, subscriber station, wireless terminal, tablet computer, smartphone, IoT device, sensor or NB-IoT device, watch or other wearable device, head-mounted display (HMD), vehicle, drone, medical device and its applications (e.g., remote surgery), industrial device and its applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. As an example, apparatus 20 may be implemented in, for example, a wireless handheld device, a wireless plug-in accessory, etc.

[0065] In some example embodiments, device 50 may include one or more processors, one or more computer-readable storage media (e.g., memory, storage device, etc.), one or more radio access components (e.g., radio interface, modem, transceiver, etc.), and / or user interface. In some embodiments, device 50 may be configured to operate using one or more radio access technologies (such as GSM, LTE, LTE-A, NR, 5G, WLAN, WiFi, NB-IoT, Bluetooth, NFC, MulteFire, and / or any other radio access technology). It should be noted that those skilled in the art will understand that device 50 may include... Figure 9 Components or features not shown in the diagram.

[0066] like Figure 9 As illustrated in the example, device 50 may include or be coupled to processor 12 for processing information and executing instructions or operations. Processor 12 may be any type of general-purpose or special-purpose processor. In practice, as an example, processor 12 may include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), and a processor based on a multi-core processor architecture. Although in Figure 9 A single processor 12 is shown, but multiple processors may be utilized according to other embodiments. For example, in some embodiments, apparatus 50 may include two or more processors that can form a multiprocessor system capable of supporting multiple processing (e.g., in this case, processor 12 may represent multiple processors). In some embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

[0067] The processor 12 can perform functions associated with the operation of the device 50, including, for example, precoding of antenna gain / phase parameters, encoding and decoding of individual bits forming communication messages, formatting of information, and overall control of the device 50, including processing related to communication resource management.

[0068] Device 50 may also include or be coupled to memory 14 (internal or external), which may be coupled to processor 12 for storing information and instructions executable by processor 12. Memory 14 may be one or more memories and may be of any type suitable for the local application environment, and may be implemented using any suitable volatile or non-volatile data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and / or removable memory. For example, memory 14 may consist of random access memory (RAM), read-only memory (ROM), static storage devices (such as disks or optical discs), hard disk drives (HDDs), or any other type of non-transitory machine or computer-readable medium, and any combination thereof. Instructions stored in memory 14 may include program instructions 15 or computer program code that, when executed by processor 12, enable device 50 to perform the tasks described herein.

[0069] In embodiments, device 50 may also include or be coupled to an (internal or external) drive or port configured to accept and read external computer-readable storage media (such as an optical disc, USB drive, flash drive, or any other storage media). For example, the external computer-readable storage media may store computer programs or software executed by processor 12 and / or device 50.

[0070] In some embodiments, device 50 may further include or be coupled to one or more antennas for receiving downlink signals and transmitting from device 50 via an uplink. Device 50 may also include a transceiver or radio interface 16 configured to transmit and receive information. Radio interface 16 may include a modem coupled to antenna 25. The radio interface may comply with one or more of various radio access technologies, including GSM, LTE, LTE-A, 5G, NR, WLAN, NB-IoT, Bluetooth, BT-LE, NFC, RFID, UWB, etc. The radio interface may include other components such as filters, converters (e.g., digital-to-analog converters), signal processing components, and inverse fast Fourier transform (IFFT) modules to process symbols carried by the downlink or uplink (such as Orthogonal Frequency Division Multiple Access (OFDMA) symbols).

[0071] For example, radio interface 16 can be configured to modulate information onto a carrier waveform for transmission via antenna(s) and demodulate information received via antenna(s) for further processing by other elements of device 50. In other embodiments, radio interface 16 can directly transmit and receive signals or data. Additionally or alternatively, in some embodiments, device 50 may include input and / or output devices (I / O devices). In some embodiments, device 50 may also include user interface 18, such as a graphical user interface or a touchscreen.

[0072] In one embodiment, memory 14 stores software modules that provide functionality when executed by processor 12. These modules may include, for example, an operating system that provides operating system functionality to device 50. The memory may also store one or more functional modules (such as applications or programs) to provide additional functionality to device 50. Components of device 50 may be implemented in hardware or as any suitable combination of hardware and software. According to an example embodiment, device 50 may optionally be configured to communicate with other devices via wireless or wired communication links according to any radio access technology, such as NR.

[0073] According to some embodiments, the processor 12 and memory 14 may be included in or form part of a processing circuit system or control circuit system. Furthermore, in some embodiments, the radio interface 16 may be included in or form part of a transceiver circuit system.

[0074] The term “non-transient” as used in this article refers to a limitation on the medium itself (i.e., tangible, not signal), rather than a limitation on the persistence of data storage (e.g., RAM versus ROM).

[0075] The term "circuit system" can refer to one or more, or all of the following:

[0076] (a) Hardware circuit implementation only (such as implementation in analog and / or digital circuits only) and

[0077] (b) A combination of hardware circuitry and software, such as (if applicable):

[0078] (i) A combination of (multiple) analog and / or digital hardware circuits and software / firmware, and

[0079] (ii) Any part of a hardware processor (including digital signal processors), software, and memory (including multiple memory), which work together to enable a device (such as a mobile phone or server) to perform various functions.

[0080] The hardware circuits and / or processors (such as microprocessors or a portion of microprocessors) that require software (e.g., firmware) to operate may be absent when the software is not required to operate.

[0081] The definition of "circuit system" applies to all uses of the term in this application, including in any claim. As another example, as used in this application, the term "circuit system" also covers only hardware circuitry or a processor (or processors) or a portion of hardware circuitry or a processor and its accompanying software and / or firmware implementation. The term "circuit system" also covers (e.g., and if applicable to a particular claim element) baseband integrated circuits or processor integrated circuits for mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing or networking devices.

[0082] While the foregoing describes embodiments of this disclosure, other and further embodiments of this disclosure may be conceived without departing from the basic scope of the invention, the scope of which is defined by the appended claims.

[0083] List of abbreviations

[0084] ACK confirmation

[0085] CSI Channel State Information

[0086] CSI-RS Channel State Information Reference Signal

[0087] CU Central Unit

[0088] HO switch

[0089] LTM L1 / L2 triggered mobility or lower layer triggered mobility

[0090] L1 Floor 1

[0091] L2 Floor 2

[0092] L3 Floor 3

[0093] MAC CE Media Access Control Element

[0094] RRC Radio Resource Control

[0095] RS reference signal

[0096] SSB Synchronization Signal Block

[0097] UCI uplink control information

[0098] UE User Equipment

Claims

1. A network node, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the network node to at least: Send a handover request to at least one candidate node; Receive handover request confirmation from the at least one candidate node, wherein the confirmation is based on a further handover process triggered by the at least one candidate node for handover, and excludes the layer 1 report configuration for the at least one candidate node based on the handover measured by layer 3. as well as Radio resource reconfiguration is sent to another device, the reconfiguration excluding the Layer 1 report configuration for the at least one candidate node.

2. The network node of claim 1, wherein the handover request and handover request confirmation are for mobility triggered by a lower layer.

3. The network node according to claim 1 or 2, wherein the reporting configuration is a layer 1 reporting configuration or a mobility reporting configuration triggered by a lower layer.

4. The network node according to claim 1 or 2, wherein if the at least one candidate node indicates that the reporting configuration for the at least one candidate node is excluded, the network node sends the radio resource reconfiguration to the other device.

5. A method for a network node, comprising: Send a handover request to at least one candidate node. Receive handover request confirmation from the at least one candidate node, wherein the confirmation is based on a further handover process triggered by the at least one candidate node for handover, and excludes the layer 1 report configuration for the at least one candidate node based on the handover measured by layer 3. as well as Radio resource reconfiguration is sent to another device, the reconfiguration excluding the Layer 1 report configuration for the at least one candidate node.

6. A computer-readable storage medium comprising program instructions that, when executed by a device, cause operations including: Send a handover request to at least one candidate node. Receive handover request confirmation from the at least one candidate node, wherein the confirmation is based on a further handover process triggered by the at least one candidate node for handover, and excludes the layer 1 report configuration for the at least one candidate node based on the handover measured by layer 3. as well as Radio resource reconfiguration is sent to another device, the reconfiguration excluding the Layer 1 report configuration for the at least one candidate node.

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