Avoiding CHO cancel or re-initiation in case of SCG reconfiguration

Abstract

An apparatus is provided that includes at least one processor and at least one memory storing instructions. The instructions, when executed by the at least one processor, cause the apparatus to at least: receive a list of features of a radio resource control (RRC) configuration, where the list is provided by a target secondary node (target SN) of a conditional switching (CHO) procedure, and where for each of the list of features of the RRC configuration, the list of features is provided by a target secondary node (target SN); the list indicates whether the change of the corresponding feature needs to cancel or re-initiate the CHO; and during the CHO procedure, based on information about secondary cell group (SCG) reconfiguration for a source secondary node (source SN), comparing the information with the list to determine whether the SCG reconfiguration needs to cancel or re-initiate the CHO procedure.

Description

Technical Field

[0001] Various example embodiments relate generally to wireless networking, and more particularly to conditional handoff in dual-connectivity wireless networking. Background Art

[0002] Wireless networking offers significant advantages for user mobility. The ability to stay connected while on the move not only provides advantages for the user, but also increases efficiency and productivity for society as a whole. As user expectations for connection reliability, data speeds, and device battery life become more demanding, the technology used for wireless networking must also keep pace. Consequently, there is a continued interest in improving wireless networking technology. Summary of the Invention

[0003] According to an aspect of the present disclosure, an apparatus includes at least one processor and at least one memory storing instructions. The instructions, when executed by the at least one processor, cause the apparatus to at least: receive a list of features configured by radio resource control (RRC), wherein the list is provided by a target secondary node (target SN) of a conditional handover (CHO) procedure, and wherein for each feature in the list of features configured by the RRC, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of CHO. The instructions further cause the apparatus to at least: during the CHO procedure, based on information about a secondary cell group (SCG) reconfiguration for a source secondary node (source SN), compare the information with the list to determine whether the SCG reconfiguration requires cancellation or re-initiation of the CHO procedure.

[0004] In one aspect of the disclosed apparatus, comparing the information with the list may include: determining that a first feature is indicated in the list provided by the target SN as a feature that, if changed, requires cancellation or re-initiation of the CHO process, and determining that the first feature is indicated in the information as a feature of the SCG reconfiguration change. When executed by at least one processor, the instructions may further cause the apparatus to at least: generate an indication to cancel or re-initiate the CHO process based on the comparison.

[0005] In one aspect of the disclosed apparatus, the indication may be a flag value. When executed by at least one processor, the instructions may further cause the apparatus to at least: send the flag value to a source master node (source MN) to cause the source MN to cancel or re-initiate the CHO process.

[0006] In one aspect of the disclosed apparatus, the instructions, when executed by at least one processor, may further cause the apparatus to at least: cancel or re-initiate the CHO process.

[0007] In one aspect of the disclosed apparatus, comparing the information with the list may include determining that there is no overlap between: features indicated in the list provided by the target SN as requiring cancellation or re-initiation of a CHO procedure if changed, and features indicated in the information as being changed by the SCG reconfiguration. When executed by at least one processor, the instructions may further cause the apparatus to at least: generate an indication to maintain the CHO procedure based on the comparison.

[0008] In one aspect of the disclosed apparatus, for each feature in the list of RRC configured features, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

[0009] In one aspect of the disclosed apparatus, the list may be implemented as a bitmap that maps bits to characteristics of the RCC configuration.

[0010] In one aspect of the disclosed apparatus, the information about the SCG reconfiguration may include a second list of RRC configured features, wherein the second list is provided by the source SN, and wherein, for each feature in the second list of RRC configured features, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

[0011] In one aspect of the disclosed apparatus, the list and the second list may be implemented as bitmaps that map bits to characteristics of an RCC configuration, wherein the list and the second list have the same bitmap structure.

[0012] According to aspects of the present disclosure, a processor-implemented method includes receiving a list of radio resource control (RRC) configured features, wherein the list is provided by a target secondary node (target SN) of a conditional handover (CHO) procedure, and wherein for each feature in the list of RRC-configured features, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of CHO. The processor-implemented method further comprises: during the CHO procedure, based on information about a secondary cell group (SCG) reconfiguration for a source secondary node (source SN), comparing the information with the list to determine whether the SCG reconfiguration requires cancellation or re-initiation of the CHO procedure.

[0013] In one aspect of the disclosed processor-implemented method, comparing the information with the list may include determining that a first characteristic is indicated in the list provided by the target SN as a characteristic that, if changed, requires cancellation or re-initiation of the CHO procedure, and determining that the first characteristic is indicated in the information as a characteristic of the SCG reconfiguration change. The processor-implemented method may also include generating an indication to cancel or re-initiate the CHO procedure based on the comparison.

[0014] In one aspect of the disclosed processor-implemented method, the indication may be a flag value. The processor-implemented method may further include: sending the flag value to a source master node (source MN) to cause the source MN to cancel or re-initiate the CHO procedure.

[0015] In one aspect of the disclosed processor-implemented method, the processor-implemented method may further include canceling or re-initiating the CHO process.

[0016] In one aspect of the disclosed processor-implemented method, comparing the information with the list may include determining that there is no overlap between the following: features indicated in the list provided by the target SN as requiring cancellation or re-initiation of a CHO procedure if changed and features indicated in the information as SCG reconfiguration changes. The processor-implemented method may also include generating an indication to maintain the CHO procedure based on the comparison.

[0017] In one aspect of the disclosed processor-implemented method, for each feature in the list of features of the RRC configuration, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

[0018] In one aspect of the disclosed processor-implemented method, the list may be implemented as a bitmap that maps bits to characteristics of the RCC configuration.

[0019] In one aspect of the disclosed processor-implemented method, the information about the SCG reconfiguration may include a second list of RRC-configured features, wherein the second list is provided by the source SN, and wherein for each feature in the second list of RRC-configured features, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

[0020] In one aspect of the disclosed processor-implemented method, the list and the second list may be implemented as bitmaps that map bits to characteristics of an RCC configuration, wherein the list and the second list have the same bitmap structure.

[0021] According to aspects of the present disclosure, a processor-implemented method includes: initiating a conditional handover (CHO) process by a source master node (source MN); generating a first list of features configured by a radio resource control (RRC) by a target secondary node (target SN), wherein for each feature in the first list of features configured by the RRC, the first list indicates whether a change in the corresponding feature requires cancellation or re-initiation of CHO; storing the first list at the source MN; generating a second list of features configured by the source secondary node (source SN), wherein for each feature in the second list of features configured by the RRC, the second list indicates whether a secondary cell group (SCG) reconfiguration for the source SN changes the corresponding feature; storing the second list at the source MN; and determining by the source MN whether to cancel or re-initiate the CHO process based on comparing the stored first list and the stored second list by the source MN.

[0022] According to aspects of the present disclosure, a processor-implemented method includes: initiating a conditional handover (CHO) process by a source master node (source MN); generating a list of features of a radio resource control (RRC) configuration by a target secondary node (target SN), wherein, for each feature in a first feature list of the RRC configuration, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of CHO; storing the list at a source secondary node (source SN); generating, by the source SN, information about a secondary cell group (SCG) reconfiguration for the source SN, wherein the information indicates features of the RRC configuration changed by the SCG reconfiguration; generating, by the source SN, an indication of whether the source MN should cancel or re-initiate the CHO process based on a comparison of the stored list and the information by the source SN; and re-initiating or maintaining the CHO process by the source MN based on the indication generated by the source SN.

[0023] According to some aspects, the subject matter of the independent claims is provided. Some further aspects are defined in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Some exemplary embodiments will now be described with reference to the accompanying drawings.

[0025] Figure 1 is a diagram of an example embodiment of dual connectivity (DC) of a user equipment device (UE) with a primary node (MN) and a secondary node (SN) according to one illustrated aspect of the present disclosure;

[0026] Figure 2 is a diagram of an example embodiment of a conditional handover (CHO) procedure involving dual connectivity (DC) according to one illustrated aspect of the present disclosure;

[0027] Figure 3A and 3B is a diagram of an example embodiment of signals and operations between a UE, a source MN, a source SN, a target MN, and a target SN according to one illustrated aspect of the present disclosure;

[0028] Figure 4A and 4B is a diagram of another example embodiment of signals and operations between a UE, a source MN, a source SN, a target MN, and a target SN according to one illustrated aspect of the present disclosure;

[0029] Figure 5 is a diagram of an example operation of a network node apparatus; and

[0030] Figure 6 is a diagram of an example embodiment of components of a device according to one illustrated aspect of the disclosure. DETAILED DESCRIPTION

[0031] In the following description, certain specific details are set forth in order to provide a thorough understanding of the disclosed aspects. However, one skilled in the relevant art will recognize that the various aspects can be practiced without one or more of these specific details, or with other methods, components, materials, etc. In other instances, well-known structures associated with transmitters, receivers, or transceivers are not shown or described in detail to avoid unnecessarily obscuring the description of the various aspects.

[0032] Reference throughout this specification to "one aspect" or "aspects" means that a particular feature, structure, or characteristic described in connection with that aspect is included in at least one aspect. Thus, the appearances of the phrases "in one aspect" or "in aspects" in various places throughout this specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more aspects.

[0033] The embodiments described in the present disclosure may be implemented in wireless networking devices, such as, but not limited to, devices utilizing Worldwide Interoperability for Microwave Access (WiMAX), Global System for Mobile Communications (GSM, 2G), GSM EDGE Radio Access Network (GERAN), General Packet Radio Service (GRPS), Universal Mobile Telecommunications System (UMTS, 3G) based on basic Wideband Code Division Multiple Access (W-CDMA), High Speed ​​Packet Access (HSPA), Long Term Evolution (LTE), LTE-Advanced, Enhanced LTE (eLTE), 5G New Radio (5G NR) and 802.11ax (Wi-Fi 6), as well as other wireless networking systems. The term "eLTE" herein refers to the evolution of LTE connected to a 5G core. LTE is also known as Evolved UMTS Terrestrial Radio Access (EUTRA) or Evolved UMTS Terrestrial Radio Access Network (EUTRAN).

[0034] Aspects of the present disclosure relate to conditional handover in dual connectivity situations. Aspects of the present disclosure provide various advantages, including avoiding cancellation or re-initiation of conditional handover initiated by a primary node in the event of secondary cell group reconfiguration in various scenarios.

[0035] Figure 1 1 is a diagram illustrating an example of dual connectivity (DC) between a user equipment device (UE) 110 and a master node (MN) 120 and a secondary node (SN) 130. UE 110 may include, but is not limited to, a smartphone, a tablet, a laptop, an in-vehicle wireless terminal device, an IoT device, and / or a watch or other wearable device. Dual connectivity allows UE 110 to be connected to two network nodes simultaneously. In embodiments, MN 120 and / or SN 130 may be a 5G New Radio (NR) node (e.g., a gNB) or an LTE network node (e.g., an eNB), among other types of nodes. In embodiments, MN 120 and / or SN 130 may be a base station.

[0036] In an embodiment, MN 120 is connected to a core network such as a 5G core (5GC) and provides a control plane connection between UE 110 and the core network, while SN 130 is connected to MN 120 (e.g., via an Xn interface) and provides additional resources for user plane services. In an embodiment, MN 120 processes signaling messages, such as radio resource control (RRC) signaling messages. In an embodiment, SN 130 may also process signaling messages, such as RRC signaling messages, using signaling radio bearers (SRBs) for LTE networks (e.g., SRB0, SRB1, and / or SRB2) and / or signaling radio bearers (SRBs) for 5G NR networks (e.g., SRB3). As will be understood by those skilled in the art, RRC is used by nodes and UEs for various radio resource operations, such as, but not limited to, connection management and mobility functions. As used herein, the term "resource" may refer to radio resources, such as physical resource blocks (PRBs), radio frames, subframes, time slots, subbands, frequency regions, subcarriers, beams, etc. As used herein, the terms "transmit" and / or "receive" may refer to wirelessly transmitting and / or receiving on radio resources via a wireless propagation channel, respectively. Those skilled in the art will understand RRC and SRB.

[0037] Carrier aggregation may be used in conjunction with dual connectivity. Carrier aggregation enables the UE 110 to be connected to multiple cells simultaneously in order to operate on multiple frequencies simultaneously. In an embodiment, the multiple cells may be located at a single base station and / or a common location (e.g., a small cell or femto cell at a facility). The one or more cells that may be used by a UE under carrier aggregation may be referred to as a "cell group". When carrier aggregation is used with dual connectivity, the primary node and / or the secondary node may have a cell group. The cell group of the primary node may be referred to as a primary cell group (MCG), and the cell group of the secondary node may be referred to as a secondary cell group (SCG). As Figure 1 As shown, an MCG includes a primary cell (PCell) and may include one or more secondary cells (SCells). An SCG includes a primary cell of a secondary cell group (PSCell) and may include one or more secondary cells (SCells). Those skilled in the art will understand the features and functions of these cells and cell groups.

[0038] In radio communications, a node may be implemented at least in part by a centralized unit CU (e.g., a server or host) operatively coupled to one or more distributed units DU (e.g., a radio head). In an embodiment, it is possible that node operations may be distributed across multiple centralized units (e.g., servers or hosts). In an embodiment, network nodes in a 5G wireless network may be implemented based on a so-called CU-DU split. In an embodiment, processing tasks may be performed in either the CU or the DU, and the transfer of responsibilities between the CU and the DU may be configured according to a specific implementation.

[0039] Figure 1 The examples are illustrative only. Figure 1 Various other arrangements are considered to be within the scope of this disclosure.

[0040] Figure 2 An example of a conditional handover procedure involving dual connectivity (DC) is described. Handover (HO) refers to the process of transferring a UE's service from a source node or cell to a target node or cell. HO can be performed, for example, when a UE transitions between cells, as well as in other situations. Figure 2 UE 110, source MN 220, source SN 230, target MN 240, and target SN 250 are shown.

[0041] The 5G 3GPP (3rd Generation Partnership Project) Release 16 standard enables Conditional Handover (CHO) operations. CHO is a process that allows the source node to define one or more execution conditions for HO and then allows the UE to perform HO when the execution conditions are met. In the case of dual connectivity, and with reference to Figure 2 , CHO may involve a handover from a source MN 220 to a target MN 240, a handover from a source SN 230 to a target SN 250, and / or a change of a PSCell within an SN. When a PSCell change is performed in a conditional manner, the PSCell change is referred to as a conditional PSCell change (CPC). For clarity, a CHO from a source MN 220 to a target MN 240 may be referred to herein as an inter-MN CHO, a conditional PSCell change from a source SN 230 to a target SN 250 may be referred to herein as an inter-SN CPC (whether MN-initiated or SN-initiated), and a CPC within an SN (e.g., within the source SN 230) may be referred to herein as an intra-SN CPC. Relevant specific standards include, but are not limited to, 3GPP TS 37.340 and TS 38.423.

[0042] In various situations, complications may arise in connection with CHO. As will be appreciated by those skilled in the art, when CHO is initially triggered, the CHO target node or cell confirms and agrees to process the UE configuration. As described above, RRC is used by the node and the UE for various radio resource operations. UE RRC reconfiguration occurring between the triggering of CHO and the execution of the handover may result in inconsistencies during the handover execution because the UE may have an RRC configuration that is different from the RRC configuration assumed by the target node or cell. As another example, where incremental configuration (i.e., a configuration that relies on a base configuration) is used, changes to the base configuration may render the incremental configuration unusable.

[0043] Potential scenarios can be even more complex. The 5G 3GPP Release 17 standard extends the CHO procedure to dual-connectivity scenarios, where the target MN 240 is also established with dual connectivity, and extends the CHO procedure so that CPC can be initiated by the source MN 220 or the source SN 230. From Release 17 onwards, in dual-connectivity scenarios, it is now possible for the source MN 220 to initiate inter-MN CHO or inter-SN CPC at the same time as the source SN 230 initiates intra-SN CPC or inter-SN CPC.

[0044] When all of these functions related to inter-MN CHO, MN-initiated CPC (inter-SN or intra-SN), and SN-initiated CPC (inter-SN or intra-SN) are enabled, the interactions between them can occur in a complex manner. For example, in some cases, the execution of CPC (or normal SCG reconfiguration) erases the CHO configuration in UE 110, which may affect the triggered inter-MN CHO. In other cases, the execution of CPC (or normal SCG reconfiguration) does not erase the CHO configuration in UE 110, but the executed CPC may still change the basic configuration of the SCG configuration, and if the target MN 240 or target SN 250 uses an already prepared incremental configuration, this may cause potential problems for such incremental configuration. In the case of incremental configuration, any change to the basic SCG configuration in UE 110 may result in the cancellation of the existing CHO (e.g., inter-MN CHO and / or MN-initiated CPC) and the possibility of re-initiating it using the new SCG configuration in UE 110. However, in some cases, the modification of the SCG configuration in the UE 110 does not affect the incremental SCG configuration created at the target SN 250 .

[0045] In various aspects, the present disclosure identifies situations when SCG reconfiguration does not require cancellation or re-initiation of inter-MN CHO and / or MN-initiated CPC. In various aspects, the present disclosure addresses avoiding cancellation or re-initiation of inter-MN CHO (and, in embodiments, avoiding cancellation or re-initiation of MN-initiated CPC) in the event of SCG reconfiguration.

[0046] Aspects of the present disclosure apply an RRC-configured feature list that notifies the source MN 220 and / or source SN 230 of changes that are allowed to be completed in the SCG configuration without affecting the prepared inter-MN CHO or MN-initiated CPC. In an embodiment, the RRC-configured feature list may be implemented as a mapping of bits (e.g., bits in a signal or message) to RRC features and may be referred to herein as a "bitmap" or "feature bitmap." As explained in more detail below in conjunction with Figures 3 and 4, the bits of the bitmap may mean different things depending on how it is used. For ease of description, the following paragraphs may include descriptions using bitmaps, but it is intended that all such descriptions will apply to RRC-configured feature lists implemented in any manner. Therefore, any description referring to a bitmap should be regarded as such description also referring to a list of RRC-configured features (implemented in any manner).

[0047] Figure 2 The examples described are illustrative only. Variations are considered to be within the scope of this disclosure.

[0048] Figure 3A / 3B and Figure 4A / 4B is a diagram of example signals and operations between a UE, a source MN, a source SN, a target MN, and a target SN in conjunction with an embodiment of a CHO operation (eg, inter-MN CHO or MN-initiated CPC). Figure 3A / 3B and Figure 4A Both SN and SN4B provide embodiments of a mechanism for determining whether SCG reconfiguration at the source SN will require the source MN to cancel or re-initiate a CHO request.

[0049] One or more of the following operations may be implemented in conjunction with the CHO operation of the present disclosure, such as Figure 3A / 3B and Figure 4A / 4B shows an example. Also see Figure 2 :

[0050] The source MN 220 controls inter-MN CHO and / or MN-initiated CPC, and the source MN 220 decides whether to cancel or re-initiate inter-MN CHO and / or MN-initiated CPC.

[0051] As long as inter-MN CHO or MN-initiated CPC is not performed, the source SN 230 controls the SCG configuration in the UE.

[0052] The SCG configuration to be used after an inter-MN CHO or MN-initiated CPC execution is controlled by the target SN 250, which defines the incremental SCG configuration and decides which parts of the base SCG configuration are to be replaced.

[0053] The MN 220, 240 does not need to decode or interpret the SCG reconfiguration it receives from its SN 230, 250 or from the target node in HO.

[0054] In various aspects of the present disclosure, Figure 3A An embodiment of / 3B implements a three-part approach. In part (1), the source MN stores an SCG bitmap (referred to as the target SN SCG bitmap) received from the target SN in connection with a CHO request (e.g., inter-MN CHO or MN-initiated CPC). The target SN SCG bitmap indicates which features of the RRC configuration, if changed, require CHO re-initiation or cancellation. In part (2), the source SN notifies the source MN about the performed SCG reconfiguration and includes a second bitmap (referred to as the source SN SCG bitmap) in the SN modification request signal sent from the source SN to the source MN. The source SN SCG bitmap has the same structure as the target SN SCG bitmap received from the target SN. However, the source SN SCG bitmap indicates which features of the RRC configuration are changed or are being changed. Thus, the source SN SCG bitmap informs the source MN what changes will be performed or have been performed. Part (3) provides a mechanism for determining when CHO cancellation or re-initiation is required or not required. In part (3), the source MN compares the target SN SCG bitmap and the source SN SCG bitmap received by the source MN in parts (1) and (2), respectively. As described above, the target SN SCG bitmap indicates which RRC configuration feature changes require CHO re-initiation or cancellation, and the source SN SCG bitmap indicates which RRC configuration features are changed or are about to be changed. Therefore, if the RRC configuration features in the SCG bitmap overlap, this indicates that the changes performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation. Based on at least one of such overlaps in the SCG bitmap, the source MN determines that it must cancel or re-initiate inter-MN CHO or MN-initiated CPC. On the other hand, if the SCG bitmap is exclusive, this indicates that the changes performed by the source SN are not changes that the target SN has indicated will require CHO re-initiation or cancellation. In this case, the source MN determines that any inter-MN CHO or MN-initiated CPC can remain as prepared.

[0055] The above part is Figure 3A This is implemented in the example CHO operation shown in / 3B, where the UE has dual connectivity with the source MN and the source SN. Figure 3A The signals and operations shown in / 3B are merely examples, and various variations are contemplated within the scope of this disclosure. For example, Figure 3A / Additional signals and / or operations not shown in 3B, and Figure 3A Some of the signals and / or operations shown in FIG. 3B may not appear or may appear in a different order.

[0056] Signals 31 and 32 are optional. For signal 31, the source MN sends an SN modification request signal (SN MODREQ) to the source SN. For signal 32, the source SN confirms the request by sending an SN modification request confirmation (SN MOD REQ ACK) signal to the source MN.

[0057] For signal 33, the source MN sends a CHO request signal (HO REQ) to the target MN. For signal 34, the target MN sends an SN add request signal (ADD REQ) to the target SN. For operation 35, the target SN prepares a target SN SCG bitmap, which indicates which features of the RRC configuration require CHO re-initiation or cancellation if changed. For signal 36, the target SN confirms the ADD REQ by sending an add request acknowledgment (ADD REQ ACK) signal to the target MN, wherein the target SN SCG bitmap is included in the acknowledgment signal. Operation 37 is optional. For operation 37, the target MN prepares an MCG bitmap. For signal 38, the target MN confirms the HO REQ by sending a handover request acknowledgment (HO REQ ACK) signal to the source MN, wherein the target SN SCG bitmap (and optionally the MCG bitmap) is included in the acknowledgment signal.

[0058] At operation 39, the source MN stores the target SN SCG bitmap. At signal(s) 310, the UE and the source MN perform RRC reconfiguration. At signal 311, the source MN sends an Xn address indication signal (Xn ADRIND) to the source SN. In the Xn ADR IND signal, the information element for CHO indication may be set to "true" or "coordination only."

[0059] At operation 312, the source SN performs SCG reconfiguration or decides to perform SCG reconfiguration. At operation 313, the source SN generates a source SN SCG bitmap, which has the same structure as the target SN SCG bitmap and indicates which features of the RRC configuration are changed or are being changed in the SCG reconfiguration. (Multiple) signals 314 are optional to signal 317. (Multiple) signals 314, the source SN and the UE can perform RRC reconfiguration according to the SCG reconfiguration using SRB3. (Multiple) signals 315, the source SN sends an SN modification request signal (SN MOD REQD) to the source MN, wherein the source SN SCG bitmap is included in the SN MOD REQD signal.

[0060] The source MN performs a comparison of the target SN SCG bitmap with the source SN SCG bitmap for operation 316. For example, the comparison may be implemented by a logical AND operation between the bitmaps.

[0061] As described above, if the RRC configuration features in the SCG bitmap overlap, a logical AND operation will result in a non-zero value, indicating that the change performed by the source SN is a change that the target SN has indicated will require CHO re-initiation or cancellation. As a result of this determination, signals and operations 319-328 may be performed, wherein the source MN re-initiates the CHO request. Signals and operations 319-326 and 328 are the same as signals and operations 33-311. With signal 327, the source MN sends an SN modification confirmation signal (SNMOD CONF) to the source SN.

[0062] On the other hand, if the SCG bitmap is exclusive, the logical AND will have a value of zero, indicating that the change performed by the source SN is not a change that the target SN has indicated will require CHO re-initiation or cancellation. As a result of this determination, signals 317 and 318 may be executed, wherein the source MN maintains the prepared HO procedure. Signal(s) 317 are optional. For signal(s) 317, the source MN and the UE may perform RRC reconfiguration via SRB1. For signal 318, the source MN confirms the SN modification by sending the signal SN MOD CONF to the source SN.

[0063] As mentioned above, Figure 3A The signals and operations shown in 3B are merely examples, and various variations are contemplated within the scope of this disclosure. For example, the RRC-configured feature list may not be implemented as a bitmap, but rather in another manner. Regardless of how the RRC-configured feature list is implemented, the source MN may compare the target SN list with the source SN list to determine whether the changes performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation. Such and other variations are contemplated within the scope of this disclosure.

[0064] In various aspects of the present disclosure, Figure 4A The embodiment of / 4B implements another three-part approach. In part (1), in conjunction with a CHO request (e.g., inter-MN CHO or MN-initiated CPC), the source MN receives the target SN SCG bitmap received from the target SN and forwards the target SN SCG bitmap to the source SN (e.g., in an "Xn Address Indication"). Figure 3AAs in / 3B, the target SN SCG bitmap indicates which features of the RRC configuration, if changed, require CHO re-initiation or cancellation. The source SN stores the target SN SCG bitmap. In part (2), when the source SN decides to perform SCG reconfiguration or performs SCG reconfiguration, it compares the changes or planned changes with the stored target SN's SCG bitmap from the target SN. If any changes or planned changes are RRC configuration features indicated in the target SN SCG bitmap as requiring cancellation or re-initiation of CHO, the source SN sets the value of a flag (e.g., flag value = 1) to indicate this determination in the notification to the source MN. Otherwise, if there are no planned changes or changes performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation, the source SN may set a flag value to indicate this determination (e.g., flag value = 0). In part (3), the source MN determines whether to cancel or re-initiate CHO based on the flag value received from the source SN.

[0065] The above part is Figure 4A This is implemented in the example CHO operation shown in / 4B, where the UE has dual connectivity with the source MN and the source SN. Figure 4A The signals and operations shown in / 4B are merely examples, and various variations are contemplated within the scope of this disclosure. For example, Figure 4A / Additional signals and / or operations not shown in 4B, and Figure 4A Some of the signals and / or operations shown in FIG. 4B may not appear or may appear in a different order.

[0066] exist Figure 4A Signals and Operations 41-48 Figure 3A The signals are the same as operations 31 to 38. Specifically, the target SN prepares a target SN SCG bitmap.

[0067] For signal(s) 49, the UE and source MN perform RRC reconfiguration. For signal 410, the source MN sends an Xn address indication signal (Xn ADRIND) to the source SN, where the target SN SCG bitmap is included in the signal. In the Xn ADRIND signal, the information element for CHO indication can be set to "true" or "coordination only." For operation 411, the source SN stores the target SN SCG bitmap.

[0068] For operation 412, the source SN performs SCG reconfiguration or decides to perform SCG reconfiguration. For operation 413, the source SN compares the changes or planned changes with the stored target SN SCG bitmap from the target SN. If any changes or planned changes are RRC configuration features indicated in the target SN SCG bitmap as requiring cancellation or re-initiation of CHO, the source SN sets a flag value to indicate the determination (e.g., flag value = 1). Otherwise, if there are no planned changes or the changes performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation, the source SN sets a flag value to indicate the determination (e.g., flag value = 0). (Multiple) signals 414 are optional for (multiple) signals 416. For (multiple) signals 414, the source SN and the UE may perform RCC reconfiguration according to the SCG reconfiguration using SRB3. For signal 415, the source SN sends an SN modification request signal (SN MOD REQD) to the source MN, wherein the flag value is included in the SN MOD REQD signal.

[0069] As described above, the source MN determines whether to cancel or re-initiate a CHO based on a flag value received from the source SN. The flag may have a value (e.g., flag value = 1) indicating that the change performed by the source SN is a change that the target SN has indicated will require CHO re-initiation or cancellation. As a result of this flag value, signals and operations 418-426 may be executed, in which the source MN re-initiates the CHO request. Signals and operations 418-424, 426 are the same as signals and operations 43-410. With respect to signal 425, the source MN confirms the SN modification by sending a signal SN MOD CONF to the source SN.

[0070] On the other hand, if there are no planned changes or the changes performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation, the source SN may set a flag value to indicate this determination (e.g., flag value = 0). As a result of this determination, signals 416 and 417 may be executed, in which the source MN maintains the prepared HO procedure. Signal(s) 416 are optional. With respect to signal(s) 416, the source MN and the UE may perform RRC reconfiguration via SRB1. With respect to signal 417, the source MN confirms the SN modification by sending a signal SN MOD CONF to the source SN.

[0071] As mentioned above, Figure 4AThe signals and operations shown in / 4B are merely examples, and various variations are contemplated within the scope of this disclosure. For example, the list of RRC-configured features may not be implemented as a bitmap, but rather in another manner. Regardless of how the list of RRC-configured features is implemented, the source SN may compare its changes or planned changes with the target SN list to determine whether the changes being performed by the source SN are changes that the target SN has indicated will require CHO re-initiation or cancellation. Such and other variations are contemplated within the scope of this disclosure.

[0072] Figure 5 5 is a diagram of example operations of a network node apparatus, such as a source MN or source SN. At block 510, the operations involve receiving a list of radio resource control (RRC) configured features, wherein the list is provided by a target secondary node (target SN) of a conditional handover (CHO) procedure, and wherein for each feature in the list of RRC configured features, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of CHO. In the case where the network node apparatus is a source MN, the source MN receives the list, such as Figure 3A / 3B. In the case where the network node device is the source SN, the source SN receives the list, such as Figure 4A / 4B.

[0073] At block 520, operations involve, during a CHO procedure, based on information about a secondary cell group (SCG) reconfiguration for a source secondary node (source SN), comparing the information with a list to determine whether the SCG reconfiguration requires cancellation or re-initiation of the CHO procedure. In the case where the network node device is the source MN, the information about the SCG reconfiguration may be a second list of features of the RRC reconfiguration that will be changed by the SCG reconfiguration, such as Figure 3A This second list will be generated by the source SN and sent to the master MN so that the master MN can compare the second list with the list from the target SN, as shown in FIG. Figure 3A In the case where the network node device is the source SN, the information about the SCG reconfiguration may be information related to the SCG reconfiguration generated in the source SN, such as Figure 4A The source SN compares this information with the list from the target SN, as shown in / 4B. Figure 4A / 4B described.

[0074] At block 530 , the operation evaluates the determination at block 520 whether to cancel or re-initiate the CHO.

[0075] If it is determined to cancel or re-initiate CHO, the operation proceeds to block 540 to generate an indication to cancel or re-initiate the CHO process based on the comparison at block 520. In the case where the network node device is the source MN, as Figure 3A As shown in FIG. 3B, the indication may be a value within the source MN, such as a value obtained from the comparison at block 520. In the case where the network node device is the source SN, as shown in FIG. Figure 4A As shown in FIG4B, the indication may be a flag value generated by the source SN.

[0076] If it is determined not to cancel or re-initiate CHO, the operation proceeds to block 550 to generate an indication to maintain the CHO process based on the comparison at block 520. In the case where the network node device is the source MN, as Figure 3A As shown in FIG. 3B, the indication may be a value within the source MN, such as a value obtained from the comparison at block 520. In the case where the network node device is the source SN, as shown in FIG. Figure 4A As shown in FIG4B, the indication may be a flag value generated by the source SN.

[0077] Figure 5 The example operations shown in are merely illustrative, and various variations are contemplated within the scope of this disclosure. Figure 5 Other operations not shown in the figure may be performed by the source MN and / or source SN or by another network node device.

[0078] Now refer to Figure 6 , a block diagram of example components of a user equipment device or network node device is shown. The device includes an electronic storage device 610, a processor 620, a memory 650, and a network interface 640. The various components can be communicatively coupled to each other. The processor 620 can be and can include any type of processor, such as a single-core central processing unit (CPU), a multi-core CPU, a microprocessor, a digital signal processor (DSP), a system on a chip (SoC), or any other type of processor. The memory 650 can be a volatile type of memory, such as RAM, or a non-volatile type of memory, such as NAND flash memory. The memory 650 includes machine-readable instructions that can be executed by the processor 520 to cause the device to perform various operations, including the above-described processes.

[0079] Electronic storage 610 may be and include any type of electronic storage device for storing data, such as a hard drive, a solid-state drive, and / or an optical disk, among other types of electronic memory. Electronic storage 610 stores software instructions for causing the apparatus to perform its operations, and stores data associated with such operations, such as data related to the 5G NR standard and other data. Network interface 640 may implement wireless networking technologies such as LTE, 5G NR, Wi-Fi 6, and / or other wireless networking technologies.

[0080] Figure 6 The components shown in the figure are merely examples, and those skilled in the art will understand that the device includes other components not shown and may include multiples of any of the components shown. Such and other embodiments are considered to be within the scope of the present disclosure.

[0081] Further embodiments of the present disclosure include the following examples.

[0082] Example 1. An apparatus comprising:

[0083] means for receiving a list of radio resource control (RRC) configured features, the list being provided by a target secondary node (target SN) of a conditional handover (CHO) procedure, wherein for each feature in the list of RRC configured features, the list indicates whether a change of the corresponding feature requires cancellation or re-initiation of CHO; and

[0084] A component for, during the CHO procedure, based on information about a secondary cell group (SCG) reconfiguration for a source secondary node (source SN), comparing the information with the list to determine whether the SCG reconfiguration requires cancellation or re-initiation of the CHO procedure.

[0085] Example 2. The apparatus of example 1, wherein comparing the information to the list comprises:

[0086] determining that the first feature is indicated in a list provided by the target SN as a feature that, if changed, requires cancellation or re-initiation of the CHO procedure, and

[0087] determining that the first characteristic is indicated in the information as a characteristic of the SCG reconfiguration change,

[0088] The apparatus also includes means for generating an indication to cancel or re-initiate the CHO procedure based on the comparison.

[0089] Example 3. The apparatus of Example 2, wherein the indication is a flag value,

[0090] The apparatus further includes a component for sending the flag value to a source master node (source MN) so that the source MN cancels or re-initiates the CHO process.

[0091] Example 4. The apparatus according to any of the preceding examples, further comprising: a component for canceling or restarting the CHO process.

[0092] Example 5. The apparatus of example 1 or example 4, wherein comparing the information with the list comprises:

[0093] Make sure there is no overlap between:

[0094] Features that are indicated in a list provided by the target SN as requiring cancellation or re-initiation of the CHO procedure if changed, and

[0095] Indicate in this message the characteristics that have changed for this SCG reconfiguration,

[0096] The apparatus also includes means for generating an indication to maintain the CHO process based on the comparison.

[0097] Example 6. An apparatus according to any of the preceding examples, wherein, for each feature in the list of features of the RRC configuration, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

[0098] Example 7. An apparatus according to any of the preceding examples, wherein the list is implemented as a bitmap that maps bits to characteristics of the RCC configuration.

[0099] Example 8. An apparatus according to any of the preceding examples, wherein the information about the SCG reconfiguration includes a second list of RRC configured features, the second list being provided by the source SN, wherein for each feature in the second list of RRC configured features, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

[0100] Example 9. The apparatus of Example 8, wherein the list and the second list are implemented as bitmaps that map bits to characteristics of an RCC configuration, the list and the second list having the same bitmap structure.

[0101] Embodiment 10. A processor-implemented method comprising:

[0102] receiving a list of radio resource control (RRC) configured features, the list being provided by a target secondary node (target SN) of a conditional handover (CHO) procedure, wherein for each feature in the list of RRC configured features, the list indicates whether a change to the corresponding feature requires cancellation or re-initiation of CHO; and

[0103] During the CHO procedure: based on information about the secondary cell group (SCG) reconfiguration for the source secondary node (source SN), the information is compared with the list to determine whether the SCG reconfiguration requires cancellation or re-initiation of the CHO procedure.

[0104] Example 11. The processor-implemented method of Example 10, wherein comparing the information to the list comprises:

[0105] determining that a first feature is indicated in the list provided by the target SN as a feature that, if changed, requires cancellation or re-initiation of a CHO procedure, and

[0106] determining that the first characteristic is indicated in the information as a characteristic of the SCG reconfiguration change,

[0107] The processor-implemented method further comprises:

[0108] An indication to cancel or re-initiate the CHO process is generated based on the comparison.

[0109] Example 12. The processor-implemented method of Example 10 or Example 11, wherein the indication is a flag value,

[0110] The processor-implemented method further comprises:

[0111] The flag value is sent to the source master node (source MN) to enable the source MN to cancel or re-initiate the CHO process.

[0112] Embodiment 13. The processor-implemented method of any one of embodiments 10-12, further comprising canceling or re-initiating a CHO process.

[0113] Example 14. The processor-implemented method of Example 10 or Example 13, wherein comparing the information to the list comprises:

[0114] Make sure there is no overlap between:

[0115] Features that are indicated in the list provided by the target SN as requiring cancellation or re-initiation of the CHO procedure if changed, and

[0116] Indicate in this message the characteristics that have changed for this SCG reconfiguration,

[0117] The processor-implemented method further comprises:

[0118] An indication to maintain the CHO process is generated based on the comparison.

[0119] Example 15. A processor-implemented method according to any of Examples 10-14, wherein, for each feature in the list of features of the RRC configuration, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

[0120] Example 16. The processor-implemented method of any of Examples 10-15, wherein the list is implemented as a bitmap that maps bits to characteristics of the RCC configuration.

[0121] Example 17. A method implemented by a processor according to any one of Examples 10-16, wherein the information about the SCG reconfiguration includes a second list of features of the RRC configuration, the second list being provided by the source SN, wherein for each feature in the second list of features of the RRC configuration, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

[0122] Example 18. The processor-implemented method of Example 17, wherein the list and the second list are implemented as bitmaps that map bits to characteristics of the RCC configuration, the list and the second list having the same bitmap structure.

[0123] The embodiments and aspects disclosed herein are examples of the present disclosure and can be embodied in various forms. For example, although some embodiments herein are described as separate embodiments, each embodiment herein can be combined with one or more other embodiments herein. The specific structural and functional details disclosed herein should not be interpreted as restrictive, but as the basis of the claims and as a representative basis for teaching those skilled in the art to adopt the present disclosure differently with any appropriate detailed structure. Throughout the description of the drawings, similar reference numerals may represent similar or identical elements.

[0124] The phrases "in aspects," "in aspects," "in various aspects," "in some aspects," or "in other aspects" may each refer to one or more of the same or different aspects according to the present disclosure. The phrase "plurality" may refer to two or more.

[0125] The phrases “in an embodiment,” “in multiple embodiments,” “in various embodiments,” “in some embodiments,” or “in other embodiments” may each refer to one or more of the same or different embodiments according to the present disclosure. A phrase of the form “A or B” means “(A), (B), or (A and B).” A phrase of the form “at least one of A, B, or C” means “(A); (B); (C); (A and B); (A and C); (B and C); or (A, B, C).”

[0126] Any of the methods, programs, algorithms or codes described herein can be converted into a programming language or computer program, or expressed in a programming language or computer program. As used herein, the terms "programming language" and "computer program" each include any language for specifying instructions to a computer, and include, but are not limited to, the following languages ​​and their derivatives: assembler, Basic, batch file, BCPL, C, C+, C++, Delphi, Fortran, Java, JavaScript, machine code, operating system command language, Pascal, Perl, PL1, Python, scripting languages, Visual Basic, the metalanguages ​​of the programs themselves, and all first, second, third, fourth, fifth or further generations of computer languages. Also included are databases and other data schemas, and any other metalanguages. No distinction is made between the languages ​​of the methods of interpretation, compilation or use of compilation and interpretation methods. No distinction is made between the compiled version and the source version of the program. Therefore, a reference to a program is a reference to any and all such states, wherein a programming language can exist in more than one state (such as source, compilation, object or link). A reference to a procedure may include the actual instructions and / or the intent of those instructions.

[0127] Although various aspects of the present disclosure are shown in the accompanying drawings, it is not intended that the present disclosure be limited thereto, as the scope of the present disclosure is as broad as the art will allow, and the specification should be read accordingly. Therefore, the foregoing description should not be construed as limiting, but merely as exemplification of particular aspects. Those skilled in the art will envision other modifications within the scope and spirit of the appended claims.

Claims

1. A device 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 apparatus to at least: receiving a list of features configured by a radio resource control (RRC), provided by a target secondary node (i.e., a target SN) of a conditional handover (CHO) procedure, wherein for each feature in the list of features configured by the RRC, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of the CHO; and During the CHO process: Based on the information about the secondary cell group SCG reconfiguration for the source secondary node, ie, the source SN, the information is compared with the list to determine whether the SCG reconfiguration requires canceling or re-initiating the CHO procedure.

2. The device according to claim 1, wherein Comparing the information to the list includes: determining that a first feature is indicated in the list provided by the target SN as a feature that, if changed, requires cancellation or re-initiation of the CHO procedure, and determining that the first characteristic is indicated in the information as a characteristic of the SCG reconfiguration change, The instructions, when executed by the at least one processor, further cause the apparatus to at least: An indication to cancel or re-initiate the CHO process is generated based on the comparison.

3. The device according to claim 2, wherein The indication is a flag value, The instructions, when executed by the at least one processor, further cause the apparatus to at least: The flag value is sent to a source master node, ie, a source MN, so that the source MN cancels or re-initiates the CHO process.

4. The device according to claim 2, wherein The instructions, when executed by the at least one processor, further cause the apparatus to at least: cancel or re-initiate the CHO process.

5. The device according to claim 1, wherein Comparing the information to the list includes: Make sure there is no overlap between: features indicated in the list provided by the target SN as requiring cancellation or re-initiation of the CHO procedure if changed, and the characteristics of the SCG reconfiguration changes indicated in the information, The instructions, when executed by the at least one processor, further cause the apparatus to at least: An indication to maintain the CHO process is generated based on the comparison.

6. The device according to claim 1, wherein For each feature in the list of features of the RRC configuration, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

7. The device according to claim 1, wherein The list is implemented as a bitmap that maps bits to characteristics of the RCC configuration.

8. The device according to claim 1, wherein The information about the SCG reconfiguration includes a second list of RRC configured features, which is provided by the source SN, wherein, for each feature in the second list of RRC configured features, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

9. The device according to claim 8, wherein The list and the second list are implemented as bitmaps that map bits to characteristics of RCC configuration, and the list and the second list have the same bitmap structure.

10. A processor-implemented method comprising: receiving a list of features configured by a radio resource control (RRC), provided by a target secondary node (i.e., a target SN) of a conditional handover (CHO) procedure, wherein for each feature in the list of features configured by the RRC, the list indicates whether a change in the corresponding feature requires cancellation or re-initiation of the CHO; and During the CHO process: Based on the information about the secondary cell group SCG reconfiguration for the source secondary node, ie, the source SN, the information is compared with the list to determine whether the SCG reconfiguration requires canceling or re-initiating the CHO procedure.

11. The processor-implemented method of claim 10, wherein: Comparing the information to the list includes: determining that a first feature is indicated in the list provided by the target SN as a feature that, if changed, requires cancellation or re-initiation of the CHO procedure, and determining that the first characteristic is indicated in the information as a characteristic of the SCG reconfiguration change, The processor-implemented method further comprises: An indication to cancel or re-initiate the CHO process is generated based on the comparison.

12. The processor-implemented method of claim 11 , wherein: The indication is a flag value, The processor-implemented method further comprises: The flag value is sent to a source master node, ie, a source MN, so that the source MN cancels or re-initiates the CHO process.

13. The processor-implemented method of claim 11 , further comprising: Cancel or re-initiate the CHO process.

14. The processor-implemented method of claim 10, wherein: Comparing the information to the list includes: Make sure there is no overlap between: features indicated in the list provided by the target SN as requiring cancellation or re-initiation of the CHO procedure if changed, and the characteristics of the SCG reconfiguration changes indicated in the information, The processor-implemented method further comprises: An indication to maintain the CHO process is generated based on the comparison.

15. The processor-implemented method of claim 10, wherein: For each feature in the list of features of the RRC configuration, the list indicates whether a future SCG reconfiguration that changes the corresponding feature requires cancellation or re-initiation of CHO.

16. The processor-implemented method of claim 10, wherein: The list is implemented as a bitmap that maps bits to characteristics of the RCC configuration.

17. The processor-implemented method of claim 10, wherein: The information about the SCG reconfiguration includes a second list of RRC configured features, which is provided by the source SN, wherein, for each feature in the second list of RRC configured features, the second list indicates whether the SCG reconfiguration changes the corresponding feature.

18. The processor-implemented method of claim 17, wherein: The list and the second list are implemented as bitmaps that map bits to characteristics of RCC configuration, and the list and the second list have the same bitmap structure.

19. A processor-implemented method comprising: The source master node (MN) initiates the conditional handover (CHO) process. generating, by the target secondary node (i.e., the target SN), a first list of features configured by a radio resource control (RRC), wherein for each feature in the first list of features configured by the RRC, the first list indicates whether a change of the corresponding feature requires cancellation or re-initiation of CHO; storing the first list at the source MN; A second list of RRC-configured features is generated by a source secondary node, i.e., a source SN, where, for each feature in the second list of RRC-configured features, the second list indicates whether a secondary cell group (SCG) reconfiguration for the source SN changes the corresponding feature; storing the second list at the source MN; as well as Based on the comparison by the source MN of the stored first list and the stored second list, the source MN determines whether to cancel or re-initiate the CHO procedure.

20. A processor-implemented method comprising: The source master node (MN) initiates the conditional handover (CHO) process. generating, by the target secondary node, i.e., the target SN, a list of features configured by radio resource control (RRC), wherein for each feature in the list of features configured by RRC, the list indicates whether a change of the corresponding feature requires cancellation or re-initiation of CHO; Storing the list at a source secondary node, i.e., a source SN; generating, by the source SN, information about secondary cell group (SCG) reconfiguration for the source SN, the information indicating characteristics of an RRC configuration changed by the SCG reconfiguration; Based on a comparison by the source SN of the stored list and the information, the source SN generates an indication as to whether the source MN should cancel or re-initiate the CHO procedure; as well as Based on the indication generated by the source SN, the CHO procedure is reinitiated or maintained by the source MN.

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