WO2024207740A1

WO2024207740A1 - Layer 1 or layer 2 triggered mobility

Info

Publication number: WO2024207740A1
Application number: PCT/CN2023/131363
Authority: WO
Inventors: Shuigen Yang; Mingzeng Dai
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2023-11-13
Filing date: 2023-11-13
Publication date: 2024-10-10
Anticipated expiration: 2026-05-13

Abstract

Various aspects of the present disclosure relate to LTM. In one aspect, a first network node receives, from a second network node, a CSI resource configuration for LTM of a UE. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The first network node determines, based on an L1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource. In turn, the first network node determines a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

Description

LAYER 1 OR LAYER 2 TRIGGERED MOBILITY

TECHNICAL FIELD

The present disclosure relates to wireless communications, and more specifically to user equipment (UE) , network nodes and methods for supporting layer 1 (L1) or layer 2 (L2) triggered mobility (LTM) .

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication devices, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

When the UE moves from one cell to another cell, at some point a serving cell change needs to be performed. In the legacy, a serving cell change is done by explicit radio resource configuration (RRC) reconfiguration signalling to trigger synchronization of a target cell based on layer 3 (L3) measurements report. It leads to longer latency, larger overhead, and longer interruption time.

In order to reduce the latency, overhead, and interruption time, LTM was proposed to change a serving cell via L1 or L2 signalling. LTM may refer to a switch procedure of a primary cell of a master cell group (also referred to as PCell) or a primary cell of a secondary cell group (also referred to as PSCell) , wherein a network device triggers the procedure via a medium access control (MAC) control element (CE) based on L1 measurements.

SUMMARY

The present disclosure relates to network nodes, UE and methods that support LTM. With the UE, network nodes and methods, a cell global identifier (CGI) for a target LTM cell may be determined. In turn, a network node may trigger an LTM cell change notification or timing advance (TA) information notification with the CGI for the target LTM cell.

Some implementations of a first network node described herein may include a processor and a transceiver coupled to the processor, wherein the processor is configured to: receive, via the transceiver from a second network node, a channel state information (CSI) resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an identifier (ID) for one of the at least one LTM candidate cell configuration and with a physical cell identifier (PCI) for one of at least one LTM candidate cell; determine, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and determine a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

In some implementations, the processor is further configured to: obtain information related to at least one association. Each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell, the at least one association comprises the first association between the first PCI and the first CGI.

In some implementations, the processor is configured to obtain the information related to the at least one association by: obtaining a neighbour cell relation table. Each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell, the at least one LTM candidate cell is configured as the at least one neighbour cell.

In some implementations, the processor is configured to obtain the neighbour cell relation table from operations administration and maintenance (OAM) or the second network node.

In some implementations, the processor is configured to obtain the information related to the at least one association from OAM.

In some implementations, the processor is configured to obtain the information related to the at least one association from the second network node.

In some implementations, the CSI resource configuration for LTM comprises the information related to the at least one association.

In some implementations, the processor is further configured to: receive a radio resource control (RRC) reconfiguration message via the transceiver from the second network node. The RRC reconfiguration message comprises the CSI resource configuration for LTM; and forward the RRC reconfiguration message via the transceiver to the UE.

In some implementations, each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is further associated with the CGI for one of the at least one LTM candidate cell.

In some implementations, the processor is further configured to: receive, via the transceiver from the second network node, at least one reference signal (RS) configuration for at least one LTM candidate cell. Each of the at least one RS configuration includes at least one second CSI resource and the PCI for one of at least one LTM candidate cell, and the second CSI resource includes the first CSI resource.

Some implementations of a second network node described herein may include a processor and a transceiver coupled to the processor, wherein the processor is configured to: transmit, via the transceiver to a first network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; and transmit, via the transceiver to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell.

In some implementations, the processor is further configured to: obtain the information related to the at least one association from OAM or a third network node providing the at least one LTM candidate cell.

In some implementations, the processor is configured to transmit the information related to the at least one association by: transmitting a neighbour cell relation table. Each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell, the at least one LTM candidate cell is configured as the at least one neighbour cell.

In some implementations, the processor is further configured to: transmit a radio resource control (RRC) reconfiguration message via the transceiver to the first network node. The RRC reconfiguration message comprises the CSI resource configuration for LTM.

In some implementations, the processor is further configured to: transmit, via the transceiver to the first network node, at least one reference signal (RS) configuration for the at least one LTM candidate cell. Each of the at least one RS configuration includes at least one second CSI resource and the PCI for one of the at least one LTM candidate cell, and the at least one second CSI resource includes the at least one first CSI resource.

Some implementations of a UE described herein may include a processor and a transceiver coupled to the processor, wherein the processor is configured to: receive an RRC reconfiguration message via the transceiver from a first network node, wherein the RRC reconfiguration message comprises a CSI resource configuration for LTM of a UE, the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration and a PCI for one of the at least one LTM candidate cell; and transmit an RRC reconfiguration complete message via the transceiver to the first network node.

In some implementations, each of the at least one first CSI resource is further associated with a cell global identifier (CGI) for one of the at least one LTM candidate cell.

Some implementations of a first network node described herein may include a processor and a transceiver coupled to the processor, wherein the processor is configured to: transmit, via the transceiver to a UE, a cell change command for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and transmit, via the transceiver to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration.

Some implementations of a second network node described herein may include a processor and a transceiver coupled to the processor, wherein the processor is configured to: receive, via the transceiver from a first network node, a cell change notification for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and determine a first CGI for a target LTM cell based on association between the first CGI and the ID for the LTM candidate cell configuration.

Some implementations of a method described herein may include: receiving, from a second network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; determining, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and determining a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

Some implementations of a method described herein may include: transmitting, to a first network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; and transmitting, to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell.

Some implementations of a method described herein may include: receiving an RRC reconfiguration message from a first network node, wherein the RRC reconfiguration message comprises a CSI resource configuration for LTM of a UE, the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration and a PCI for one of the at least one LTM candidate cell; and transmitting an RRC reconfiguration complete message to the first network node.

Some implementations of a method described herein may include: transmitting, to a UE, a cell change command for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and transmitting, to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration.

Some implementations of a method described herein may include: receiving, from a first network node, a cell change notification for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and determining a first CGI for a target LTM cell based on association between the first CGI and the ID for the LTM candidate cell configuration.

Some implementations of a processor described herein may include at least one memory and a controller coupled with the at least one memory and configured to cause the controller to: receiving, from a second network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; determining, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and determining a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 illustrates an example of a wireless communications system that supports LTM in accordance with aspects of the present disclosure;

Fig. 2A illustrates another example of a wireless communications system that supports LTM in accordance with aspects of the present disclosure;

Fig. 2B illustrates a further example of a wireless communications system that supports LTM in accordance with aspects of the present disclosure;

Figs. 3 to 8 illustrate a signaling diagram illustrating an example process that supports LTM in accordance with aspects of the present disclosure, respectively;

Fig. 9 illustrates an example of a device that supports LTM in accordance with some aspects of the present disclosure;

Fig. 10 illustrates an example of a processor that supports LTM in accordance with aspects of the present disclosure; and

Figs. 11, 12, 13, 14 and 15 illustrate a flowchart of a method that supports LTM in accordance with aspects of the present disclosure, respectively.

DETAILED DESCRIPTION

Principles of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein may be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As described above, in order to reduce the latency, overhead, and interruption time, LTM was proposed to change a serving cell via L1 or L2 signalling. In the LTM, different identifiers (IDs) may be used in different messages.

For example, the LTM-CandidateID may be used in an LTM cell switch command. The LTM-CandidateID may be used to identify an LTM candidate configuration. For another example, a new radio (NR) cell global identifier (CGI) may be used in an LTM cell change notification from a distributed unit (DU) to a central unit (CU) , early synchronization information transfer in a UE context modification request, and in a TA information notification. The NR CGI may be used to identify an LTM candidate cell. For a further example, a physical cell identifier (PCI) may be used in a reference signal (RS) configuration in an LTM channel state information (CSI) resource configuration. The PCI may be used to identify an LTM candidate cell.

In the present disclosure, the term “identifier” may be used interchangeably with the term “identity” .

Taking the different IDs used in the LTM into account, the following issues should be considered: how to determine the NR CGI of a target cell based on an L1 measurement report by the source DU, in order to trigger an LTM cell change notification or the timing advance (TA) information notification.

In view of the above, the present disclosure provides a solution that supports LTM. In this solution, a first network node receives, from a second network node, a CSI resource configuration for LTM of a UE. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The first network node determines, based on an L1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource. In turn, the first network node determines a first CGI for the target LTM cell based on first association between the first PCI and the first CGI. In this way, the first network node may determine the CGI for the target LTM cell. Then the first network node may trigger an LTM cell change notification or the TA information notification with the CGI for the target LTM cell.

Aspects of the present disclosure are described in the context of a wireless communications system.

Fig. 1 illustrates an example of a wireless communications system 100 that supports LTM in accordance with aspects of the present disclosure. The wireless communications system 100 may include one at least one of network entities 102 (also referred to as network equipment (NE) ) , one or more terminal devices or UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including institute of electrical and electronics engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station (BS) , a network element, a radio access network (RAN) node, a base transceiver station, an access point, a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface. The network entities 102 may be collectively referred to as network entities 102 or individually referred to as a network entity 102. Hereinafter, some implementations of the present disclosure will be described by taking a gNB as an example of the network entity 102. Thus, the network entity 102 may be used interchangeably with the gNB 102.

A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc. ) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non- terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an internet-of-things (IoT) device, an internet-of-everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100. In some other implementations, a UE 104 may be mobile in the wireless communications system 100.

The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in Fig. 1. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment) , as shown in Fig. 1. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100.

A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102) . In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106) . In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open radio access network (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 102 may include one or more of a CU, a DU, a radio unit (RU) , a RAN intelligent controller (RIC) (e.g., a near-real time RIC (Near-RT RIC) , a non-real time RIC (Non-RT RIC) ) , a service management and orchestration (SMO) system, or any combination thereof.

An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations) . In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., an L3, an L2) functionality and signaling (e.g., radio resource control (RRC) , service data adaption protocol (SDAP) , packet data convergence protocol (PDCP) ) . The CU may be connected to one or more DUs or RUs, and the one or more DUs or RUs may host lower protocol layers, such as an L1 (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU.

Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs) . In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU) .

A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., F1, F1-c, F1-u) , and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface) . In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links.

The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a packet data network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106) .

In the wireless communications system 100, the network entities 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

Fig. 2A illustrates another example of a wireless communications system 200A that supports LTM in accordance with aspects of the present disclosure. As shown in Fig. 2A, the wireless communications system 200A may comprise a first network node 210, a second network node 220, a third network node 230 and the UE 104. Both the first network node 210 and the third network node 230 are connected to the second network node 220.

In some implementations, the first network node 210, the second network node 220, and the third network node 230 may be collectively implemented as one of the following: a gNB, a base station, a network element, a RAN node, a base transceiver station, an access point, a NodeB, or an eNB. For example, the first network node 210, the second network node 220, and the third network node 230 may be collectively implemented as the gNB 102-1 in Fig. 1.

In the wireless communications system 200A, the second network node 220 may be implemented as a gNB-CU, and each of the first network node 210 and the third network node 230 may be implemented as a gNB-DU. In such implementations, the first network node 210, the second network node 220, and the third network node 230 may be referred to as a gNB-DU 210, a gNB-CU 220 and a gNB-DU 230, respectively.

In some implementations, the gNB-CU may be a logical node hosting RRC, SDAP and PDCP protocols of the gNB or RRC and PDCP protocols of the en-gNB that controls the operation of one or more gNB-DUs. The gNB-CU terminates the F1 interface connected to the gNB-DU.

In some implementations, the gNB-DU may be a logical node hosting RLC, MAC and PHY layers of the gNB or en-gNB, and its operation is partly controlled by gNB-CU. One gNB-DU supports one or multiple cells. One cell is supported by only one gNB-DU. The gNB-DU terminates the F1 interface connected with the gNB-CU.

Fig. 2B illustrates another example of a wireless communications system 200B that supports LTM in accordance with aspects of the present disclosure.

The wireless communications system 200B is different from the wireless communications system 200A in that the wireless communications system 200B further comprises a fourth network node 240. The first network node 210 and the second network node 220 may be collectively implemented as one of the following: a gNB, a base station, a network element, a RAN node, a base transceiver station, an access point, a NodeB, or an eNB. The third network node 230 and the fourth network node 240 may be collectively implemented as one of the following: a gNB, a base station, a network element, a RAN node, a base transceiver station, an access point, a NodeB, or an eNB. For example, the first network node 210 and the second network node 220 may be collectively implemented as the gNB 102-1 in Fig. 1, and the third network node 230 and the fourth network node 240 may be collectively implemented as the gNB 102-2 in Fig. 1.

In the wireless communications system 200B, the second network node 220 may be implemented as a first gNB-CU and the first network node 210 may be implemented as a gNB-DU connected to the first gNB-CU, and the fourth network node 240 may be implemented as a second gNB-CU and the third network node 230 may be implemented as a gNB-DU connected to the second gNB-CU. The second network node 220 may be connected to the fourth network node 240 through an Xn interface.

In some implementations, the UE 104 may move from a cell provided by one source network node (such as one gNB-DU) to a cell provided by a target network node (such as another gNB-DU) .

For example, in some implementations, the UE 104 may move from a cell provided by the first network node 210 to a cell provided by the third network node 230. In this example, the first network node 210 may be referred to as a source network node (such as a source gNB-DU) , and the third network node 230 may be referred to as a target network node (such as a target gNB-DU) .

For another example, in some implementations, the UE 104 may move from a cell provided by the third network node 230 to a cell provided by a further network node (not shown) . In this example, the third network node 230 may be referred to as a source network node (such as a source gNB-DU) , and the further network node may be referred to as a target network node (such as a target gNB-DU) .

In order to reduce the latency, overhead, and interruption time, the first network node 210 may triggers an LTM cell change procedure via an MAC CE based on L1 measurements for the UE 104.

Fig. 3 illustrates a signaling diagram illustrating an example process 300 that supports LTM in accordance with aspects of the present disclosure. The process 300 may involve the UE 104, a source network node and a network node connected to the source network node.

As described above, in some implementations, the UE 104 may move from a cell provided by the first network node 210 to a cell provided by the third network node 230. In such implementations, the first network node 210 may act as a source network node, and the third network node 230 may act as a target network node. In such implementations, the process 300 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B.

Alternatively, in some implementations, the UE 104 may move from a cell provided by the third network node 230 to a cell provided by a further network node (not shown) . In such implementations, the third network node 230 may act as a source network node, and the further network node may act as a target network node. In such implementations, the process 300 may involve the UE 104, the third network node 230 and the second network node 220 in Fig. 2A.

For the purpose of discussion, the process 300 and some example implementations of the process 300 will be described by taking the first network node 210 as an example of a source network node. Thus, the process 300 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B.

As shown in Fig. 3, the first network node 210 receives 310, from the second network node 220, a CSI resource configuration for LTM of the UE 104. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell.

Upon receiving the CSI resource configuration for LTM, the first network node 210 may store the CSI resource configuration for LTM.

In some implementations, an LTM candidate cell may refer to a candidate cell configured to the UE 104 for LTM. There may be multiple LTM candidate cells prepared for the UE 104. The LTM candidate cells may belong to the same or different candidate nodes.

In some implementations, an LTM candidate cell configuration may refer to a configuration associated with an LTM candidate cell. For example, the LTM candidate cell configuration may include at least one of the following: a configuration used to perform the early uplink synchronization procedure, a list of uplink transmission configuration indicator, radio bearer configuration, physical channel configuration, or information for mobility control.

In some implementations, each LTM candidate cell configuration may be identified by an ID or index. An ID for an LTM candidate cell configuration is also referred to as an LTM candidate cell configuration ID. An index for an LTM candidate cell configuration is also referred to as an LTM candidate cell configuration index. For example, an LTM candidate cell configuration ID or an LTM candidate cell configuration index may be LTM-CandidateId, which is used to identify an LTM candidate cell configuration.

Consider a first example. In this example, the CSI resource configuration for LTM may indicate CSI resource #1, CSI resource #2 and CSI resource #3. The CSI resource #1 is associated with LTM-CandidateId #1 and PCI #1 for LTM candidate cell #1. The CSI resource #2 is associated with LTM-CandidateId #2 and PCI #2 for LTM candidate cell #2. The CSI resource #3 is associated with LTM-CandidateId #3 and PCI #3 for LTM candidate cell #3.

It shall be understood that in other examples, multiple CSI resources may be associated with an LTM candidate cell configuration ID and with a PCI for an LTM candidate cell.

In some implementations, the first network node 210 may receive, from the second network node 220, at least one RS configuration for the at least one LTM candidate cell. Each of the at least one RS configuration includes at least one second CSI resource and the PCI for one of at least one LTM candidate cell. The at least one second CSI resource includes the at least one first CSI resource. It shall be understood that the CSI resource configuration for LTM may indicate CSI resource #1, CSI resource #2 and CSI resource #3, where the CSI resource #1 is associated with LTM-CandidateId #1, the CSI resource #2 is associated with LTM-CandidateId #2, and the CSI resource #3 is associated with LTM-CandidateId #3. That is, the CSI resource in the CSI resource configuration is not associated with the PCI of the LTM candidate cell directly. Based on the RS configuration, the CSI resource #1 is associated with PCI #1 for LTM candidate cell #1, the CSI resource #2 is associated with PCI #2 for LTM candidate cell #2, and the CSI resource #3 is associated with PCI #3 for LTM candidate cell #3.

In some implementations, the first network node 210 may receive a UE context modification request message from the second network node 220. The UE context modification request message may comprise an LTM-CSI-ResourceConfig information element (IE) generated by the second network node 220. The LTM-CSI-ResourceConfig information element IE may comprise the CSI resource configuration for LTM.

In some implementations, the UE context modification request message may further comprise the at least one RS configuration for the at least one LTM candidate cell.

The first network node 210 determines to execute cell switch to a target LTM cell. The target LTM cell is one of the at least one LTM candidate cell. In turn, the first network node 210 determines 320 a first PCI for the target LTM cell based on an L1 measurement report from the UE 104. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource.

Still consider the first example. As described above, in the first example, the CSI resource #1 is associated with LTM-CandidateId #1 and PCI #1 for LTM candidate cell #1. The CSI resource #2 is associated with LTM-CandidateId #2 and PCI #2 for LTM candidate cell #2. The CSI resource #3 is associated with LTM-CandidateId #3 and PCI #3 for LTM candidate cell #3.

In the first example, the L1 measurement report may comprise measurement result #1 for CSI resource #1, measurement result #2 for CSI resource #2, and measurement result #3 for CSI resource #3.

In the first example, the first network node 210 may select LTM candidate cell #3 as a target LTM cell based on the L1 measurement report. Because the CSI resource #3 is associated with LTM-CandidateId #3 and PCI #3 for LTM candidate cell #3, the first network node 210 may determine LTM-CandidateId #3 and PCI #3 for LTM candidate cell #3 based on measurement result #3 for CSI resource #3.

In turn, the first network node 210 determines 330 a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

In some implementations, the first network node 210 may obtain information related to at least one association. Each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell. The at least one association comprises the first association between the first PCI and the first CGI for the target LTM cell.

Alternatively, in some implementations, the at least one association may be pre-defined.

With the process 300, the first network node 210 may determine the CGI for the target LTM cell. In turn, the first network node 210 may trigger an LTM cell change notification or the TA information notification with the CGI for the target LTM cell.

Hereinafter, some implementations for obtaining the at least one association will be described with reference to Figs. 4 to 6.

Fig. 4 illustrates a signaling diagram illustrating an example process 400 that supports LTM in accordance with aspects of the present disclosure. The process 400 may be considered as an example implementation of the process 300. The process 400 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B and an OAM 250 which is not shown in Fig. 1, 2A or 2B. For the purpose of discussion, the process 400 will be described with reference to Fig. 2A or 2B.

Generally, in the process 400, the first network node 210 may obtain the information related to the at least one association from the OAM 250.

As shown in Fig. 4, the first network node 210 receives 410, from the second network node 220, a CSI resource configuration for LTM of the UE 104. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The action 410 in the process 400 is similar to the action 310 in the process 300. Details of this action are omitted for brevity.

The first network node 210 obtains 420 the information related to the at least one association from the OAM 250. In other words, the at least one association may be configured by the OAM 250. Each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell. The at least one association comprises the first association between the first PCI and the first CGI for the target LTM cell.

In some implementations, the first network node 210 may obtain the information related to the at least one association by obtaining a neighbour cell relation table from the OAM 250. In other words, the neighbour cell relation table may be configured by the OAM 250. Each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell. The at least one LTM candidate cell is configured as the at least one neighbour cell.

Upon obtaining the information related to the at least one association, the first network node 210 may maintain or store the information related to the at least one association.

Then, the first network node 210 transmits 430 an RRC reconfiguration message to the UE 104. The RRC reconfiguration message comprises the CSI resource configuration for LTM.

In some implementations, the RRC reconfiguration message may further comprise the at least one RS configuration for the at least one LTM candidate cell.

In some implementations, the RRC reconfiguration message may further comprise the at least one LTM candidate cell configuration.

In some implementations, the first network node 210 may receive the RRC reconfiguration message from the second network node 220. Then, the first network node 210 may forward the RRC reconfiguration message to the UE 104.

Upon receiving the RRC reconfiguration message, the UE 104 transmits 440 an RRC reconfiguration complete message to the first network node 210.

In turn, the UE 104 may perform early synchronization with the at least one LTM candidate cell.

Then, the UE 104 transmits 450 an L1 measurement report to the first network node 210. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource.

The first network node 210 determines to execute cell switch to a target LTM cell. The target LTM cell is one of the at least one LTM candidate cell. In turn, the first network node 210 determines 460 a first PCI for the target LTM cell based on the L1 measurement report from the UE 104. The action 460 in the process 400 is similar to the action 320 in the process 300. Details of this action are omitted for brevity.

In turn, the first network node 210 determines 470 a first CGI for the target LTM cell based on first association between the first PCI and the first CGI obtained from the OAM 250.

After that, the first network node 210 transmits 480 an LTM cell switch command to the UE 104. The LTM cell switch command comprises an ID for the target LTM cell configuration. For example, in the first example as described above, the LTM cell switch command may comprise LTM-CandidateId #3 for the target LTM cell configuration.

Upon receiving the LTM cell switch command, the UE 104 switches to the target LTM cell and applies the target LTM cell configuration indicated by the ID for the target LTM cell configuration. For example, in the first example as described above, the UE 104 switches to the target LTM cell #3 and applies the target LTM cell configuration indicated by LTM-CandidateId #3.

The first network node 210 transmits 490 an LTM cell change notification to the second network node 220 to indicate the initiation of the LTM cell switch command to the UE 104. The LTM cell change notification may comprise the first CGI for the target LTM cell.

Fig. 5 illustrates a signaling diagram illustrating an example process 500 that supports LTM in accordance with aspects of the present disclosure. The process 500 may be considered as another example implementation of the process 300. The process 500 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B. For the purpose of discussion, the process 500 will be described with reference to Fig. 2A or 2B.

Generally, in the process 500, the first network node 210 may obtain the information related to the at least one association from the second network node 220.

The actions 410, 430, 440, 450, 460, 470, 480 and 490 in the process 500 are similar to those in the process 400. Details of these actions are omitted for brevity.

The process 500 is different from the process 400 in an action 520.

Specifically, the first network node 210 obtains 520 the information related to the at least one association from the second network node 220. Each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell. The at least one association comprises the first association between the first PCI and the first CGI for the target LTM cell.

In some implementations, the first network node 210 may obtain the information related to the at least one association by obtaining a neighbour cell relation table from the second network node 220. Each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell. The at least one LTM candidate cell is configured as the at least one neighbour cell.

In some implementations, the first network node 210 may receive a CU configuration update message from the second network node 220. The CU Configuration Update message may comprise the neighbour cell relation table.

Alternatively, the CU Configuration Update message may comprise a neighbour cell information list IE. The neighbour cell information list IE comprises a PCI and a CGI of each of at least one neighbour cell. The at least one LTM candidate cell is configured as the at least one neighbour cell.

In such implementations, upon receiving the CU configuration update message, the first network node 210 may transmit a CU configuration update acknowledge message to the second network node 220.

Alternatively, in some implementations, the first network node 210 may receive a UE context modification request message from the second network node 220. The UE context modification request message may comprise at least one LTM indicator. Each of the at least one LTM indicator may comprise a PCI and a CGI for an LTM candidate cell. In such implementations, upon receiving the UE context modification request message, the first network node 210 may transmit a UE context modification response message to the second network node 220. In some implementations, each of the at least one LTM indicator may comprise an LTM-CandidateID, a PCI and a CGI for an LTM candidate cell. In some implementations, each of the at least one LTM indicator may comprise an LTM-CandidateID and a CGI for an LTM candidate cell.

Alternatively, in some implementations, the first network node 210 may receive a downlink (DL) RRC message transfer message from the second network node 220. The DL RRC message transfer message may comprise the information related to the at least one association. In such implementations, upon receiving the DL RRC message transfer message, the first network node 210 may transmit an uplink (UL) RRC message transfer message to the second network node 220.

In some implementations, the second network node 220 may obtain the information related to the at least one association from the OAM 250. Alternatively, the second network node 220 may obtain the information related to the at least one association from the third network node 230 via the fourth network node 240. The third network node 230 provides the at least one LTM candidate cell.

Fig. 6 illustrates a signaling diagram illustrating an example process 600 that supports LTM in accordance with aspects of the present disclosure. The process 600 may be considered as a further example implementation of the process 300. The process 600 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B. For the purpose of discussion, the process 600 will be described with reference to Fig. 2A or 2B.

Generally, in the process 600, the CSI resource configuration for LTM comprises the information related to the at least one association. Each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is associated with the following: an ID for one of the at least one LTM candidate cell configuration, a PCI for one of at least one LTM candidate cell and a CGI for the one of the at least one LTM candidate cell.

The actions 430, 440, 450, 460, 470, 480 and 490 in the process 600 are similar to those in the process 400. Details of these actions are omitted for brevity.

The process 600 is different from the processes 400 and 500 in actions 610 and 630.

Specifically, the first network node 210 receives 610, from the second network node 220, a CSI resource configuration for LTM of the UE 104.

The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. The CSI resource configuration for LTM further comprises the information related to the at least one association. Each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is associated with the following: an ID for one of the at least one LTM candidate cell configuration, a PCI for one of at least one LTM candidate cell and a CGI for the one of the at least one LTM candidate cell.

In some implementations, the first network node 210 may receive a UE context modification request message from the second network node 220. The UE context modification request message comprises the CSI resource configuration for LTM of the UE 104. In such implementations, upon receiving the UE context modification request message, the first network node 210 may transmit a UE context modification response message to the second network node 220.

Then, the first network node 210 transmits 630 an RRC reconfiguration message to the UE 104. The RRC reconfiguration message comprises the CSI resource configuration for LTM. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration, a PCI for one of at least one LTM candidate cell and a CGI for the one of the at least one LTM candidate cell.

Fig. 7 illustrates a signaling diagram illustrating an example process 700 that supports LTM in accordance with aspects of the present disclosure. The process 700 may be considered as a further example implementation of the process 300. The process 700 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B. For the purpose of discussion, the process 700 will be described with reference to Fig. 2A or 2B.

Generally, in the process 700, each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is associated with the following: an ID for one of the at least one LTM candidate cell configuration, and a CGI for the one of the at least one LTM candidate cell.

The actions 440, 450, 480 and 490 in the process 700 are similar to those in the process 400. Details of these actions are omitted for brevity.

The process 700 is different from the processes 400, 500 and 600 in actions 710, 730 and 760.

Specifically, the first network node 210 receives 710, from the second network node 220, a CSI resource configuration for LTM of the UE 104.

The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration, and a CGI for one of the at least one LTM candidate cell.

Then, the first network node 210 transmits 730 an RRC reconfiguration message to the UE 104. The RRC reconfiguration message comprises the CSI resource configuration for LTM. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration, and a CGI for the one of the at least one LTM candidate cell.

Consider a second example. In this example, the CSI resource configuration for LTM may indicate CSI resource #1, CSI resource #2 and CSI resource #3. The CSI resource #1 is associated with LTM-CandidateId #1 and CGI #1 for LTM candidate cell #1. The CSI resource #2 is associated with LTM-CandidateId #2 and CGI #2 for LTM candidate cell #2. The CSI resource #3 is associated with LTM-CandidateId #3 and CGI #3 for LTM candidate cell #3.

It shall be understood that in other examples, multiple CSI resources may be associated with an LTM candidate cell configuration ID and with a CGI for an LTM candidate cell.

In some implementations, the first network node 210 may receive a UE context modification request message from the second network node 220. The UE context modification request message may comprise an LTM-CSI-ResourceConfig IE generated by the second network node 220. The LTM-CSI-ResourceConfig information element IE may comprise the CSI resource configuration for LTM.

The first network node 210 determines to execute cell switch to a target LTM cell. The target LTM cell is one of the at least one LTM candidate cell. In turn, the first network node 210 determines 760, based on an L1 measurement report from the UE 104, an ID for a target LTM cell configuration and a first CGI for a target LTM cell. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource.

Still consider the second example. As described above, in the second example, the CSI resource #1 is associated with LTM-CandidateId #1 and CGI #1 for LTM candidate cell #1. The CSI resource #2 is associated with LTM-CandidateId #2 and CGI #2 for LTM candidate cell #2. The CSI resource #3 is associated with LTM-CandidateId #3 and CGI #3 for LTM candidate cell #3.

In the second example, the L1 measurement report may comprise measurement result #1 for CSI resource #1, measurement result #2 for CSI resource #2, and measurement result #3 for CSI resource #3.

In the second example, the first network node 210 may select LTM candidate cell #3 as a target LTM cell based on the L1 measurement report. Because the CSI resource #3 is associated with LTM-CandidateId #3 and CGI #3 for LTM candidate cell #3, the first network node 210 may determine LTM-CandidateId #3 and CGI #3 for LTM candidate cell #3 based on measurement result #3 for CSI resource #3.

Fig. 8 illustrates a signaling diagram illustrating an example process 800 that supports LTM in accordance with aspects of the present disclosure. The process 800 may involve the UE 104, the first network node 210 and the second network node 220 in Fig. 2A or 2B. For the purpose of discussion, the process 800 will be described with reference to Fig. 2A or 2B.

Generally, in the process 800, the first network node 210 does not have information related to association between an ID for one of the at least one LTM candidate cell configuration and a CGI for the one of the at least one LTM candidate cell. In addition, the first network node 210 does not have information related to association between a PCI and a CGI for one of the at least one LTM candidate cell.

As shown in Fig. 8, the first network node 210 receives 810, from the second network node 220, a CSI resource configuration for LTM of the UE 104. The CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration. Each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The action 810 in the process 800 is similar to the action 310 in the process 300. Details of this action are omitted for brevity.

Then, the first network node 210 transmits 820 an RRC reconfiguration message to the UE 104. The RRC reconfiguration message comprises the CSI resource configuration for LTM.

Upon receiving the RRC reconfiguration message, the UE 104 transmits 830 an RRC reconfiguration complete message to the first network node 210.

Then, the UE 104 transmits 840 an L1 measurement report to the first network node 210. The L1 measurement report comprises at least one measurement result for the at least one first CSI resource.

The first network node 210 determines to execute cell switch to a target LTM cell. The target LTM cell is one of the at least one LTM candidate cell. In turn, the first network node 210 determines 850 an ID for a target LTM cell configuration based on the L1 measurement report from the UE 104.

After that, the first network node 210 transmits 860 an LTM cell switch command to the UE 104. The LTM cell switch command comprises the ID for the target LTM cell configuration. For example, in the first example as described above, the LTM cell switch command may comprise LTM-CandidateId #3 for the target LTM cell configuration.

The first network node 210 transmits 870 an LTM cell change notification to the second network node 220 to indicate the initiation of the LTM cell switch command to the UE 104. The LTM cell change notification may comprise the ID for the target LTM cell configuration.

Upon receiving the LTM cell change notification, the second network node 220 determines 880 a first CGI for the target LTM cell based on the ID for the target LTM cell configuration. Since the ID for each LTM candidate cell configuration is assigned by the second network node 220, the second network node 220 knows the association between the ID for each LTM candidate cell configuration and the CGI for each LTM candidate cell.

Fig. 9 illustrates an example of a device 900 that supports LTM in accordance with aspects of the present disclosure. The device 900 may be an example of a network entity 102 or a UE 104 as described herein. The device 900 may support wireless communication with one or more network entities 102, UEs 104, or any combination thereof. The device 900 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 902, a memory 904, a transceiver 906, and, optionally, an I/O controller 908. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 902, the memory 904, the transceiver 906, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 902, the memory 904, the transceiver 906, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 902, the memory 904, the transceiver 906, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 902 and the memory 904 coupled with the processor 902 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 902, instructions stored in the memory 904) .

For example, the processor 902 may support wireless communication at the device 900 in accordance with examples as disclosed herein. The processor 902 may be configured to operable to support a means for performing the following: receiving, from a second network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; determining, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and determining a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

Alternatively, in some implementations, the processor 902 may be configured to operable to support a means for performing the following: transmitting, to a first network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; and transmitting, to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell.

Alternatively, in some implementations, the processor 902 may be configured to operable to support a means for performing the following: receiving an RRC reconfiguration message from a first network node, wherein the RRC reconfiguration message comprises a CSI resource configuration for LTM of a UE, the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration and a PCI for one of the at least one LTM candidate cell; and transmitting an RRC reconfiguration complete message to the first network node.

Alternatively, in some implementations, the processor 902 may be configured to operable to support a means for performing the following: transmitting, to a UE, a cell change command for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and transmitting, to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration.

Alternatively, in some implementations, the processor 902 may be configured to operable to support a means for performing the following: receiving, from a first network node, a cell change notification for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and determining a first CGI for a target LTM cell based on association between the first CGI and the ID for the LTM candidate cell configuration.

The processor 902 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 902 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 902. The processor 902 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 904) to cause the device 900 to perform various functions of the present disclosure.

The memory 904 may include random access memory (RAM) and read-only memory (ROM) . The memory 904 may store computer-readable, computer-executable code including instructions that, when executed by the processor 902 cause the device 900 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 902 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 904 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 908 may manage input and output signals for the device 900. The I/O controller 908 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 908 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 908 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 908 may be implemented as part of a processor, such as the processor 906. In some implementations, a user may interact with the device 900 via the I/O controller 908 or via hardware components controlled by the I/O controller 908.

In some implementations, the device 900 may include a single antenna 910. However, in some other implementations, the device 900 may have more than one antenna 910 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 906 may communicate bi-directionally, via the one or more antennas 910, wired, or wireless links as described herein. For example, the transceiver 906 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 906 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 910 for transmission, and to demodulate packets received from the one or more antennas 910. The transceiver 906 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 910 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 910 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

Fig. 10 illustrates an example of a processor 1000 that supports LTM in accordance with aspects of the present disclosure. The processor 1000 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 1000 may include a controller 1002 configured to perform various operations in accordance with examples as described herein. The processor 1000 may optionally include at least one memory 1004, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 1000 may optionally include one or more arithmetic-logic units (ALUs) 1006. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 1000 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 1000) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 1002 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 1000 to cause the processor 1000 to support various operations in accordance with examples as described herein. For example, the controller 1002 may operate as a control unit of the processor 1000, generating control signals that manage the operation of various components of the processor 1000. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 1002 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 1004 and determine subsequent instruction (s) to be executed to cause the processor 1000 to support various operations in accordance with examples as described herein. The controller 1002 may be configured to track memory address of instructions associated with the memory 1004. The controller 1002 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 1002 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 1000 to cause the processor 1000 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 1002 may be configured to manage flow of data within the processor 1000. The controller 1002 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 1000.

The memory 1004 may include one or more caches (e.g., memory local to or included in the processor 1000 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 1004 may reside within or on a processor chipset (e.g., local to the processor 1000) . In some other implementations, the memory 1004 may reside external to the processor chipset (e.g., remote to the processor 1000) .

The memory 1004 may store computer-readable, computer-executable code including instructions that, when executed by the processor 1000, cause the processor 1000 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 1002 and/or the processor 1000 may be configured to execute computer-readable instructions stored in the memory 1004 to cause the processor 1000 to perform various functions. For example, the processor 1000 and/or the controller 1002 may be coupled with or to the memory 1004, the processor 1000, the controller 1002, and the memory 1004 may be configured to perform various functions described herein. In some examples, the processor 1000 may include multiple processors and the memory 1004 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 1006 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 1006 may reside within or on a processor chipset (e.g., the processor 1000) . In some other implementations, the one or more ALUs 1006 may reside external to the processor chipset (e.g., the processor 1000) . One or more ALUs 1006 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 1006 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 1006 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 1006 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 1006 to handle conditional operations, comparisons, and bitwise operations.

The processor 1000 may support wireless communication in accordance with examples as disclosed herein. The processor 1000 may be configured to operable to support a means for performing the following: receiving, from a second network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; determining, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and determining a first CGI for the target LTM cell based on first association between the first PCI and the first CGI.

Alternatively, in some implementations, the processor 1000 may be configured to operable to support a means for performing the following: transmitting, to a first network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell; and transmitting, to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell.

Alternatively, in some implementations, the processor 1000 may be configured to operable to support a means for performing the following: receiving an RRC reconfiguration message from a first network node, wherein the RRC reconfiguration message comprises a CSI resource configuration for LTM of a UE, the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration and a PCI for one of the at least one LTM candidate cell; and transmitting an RRC reconfiguration complete message to the first network node.

Alternatively, in some implementations, the processor 1000 may be configured to operable to support a means for performing the following: transmitting, to a UE, a cell change command for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and transmitting, to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration.

Alternatively, in some implementations, the processor 1000 may be configured to operable to support a means for performing the following: receiving, from a first network node, a cell change notification for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration; and determining a first CGI for a target LTM cell based on association between the first CGI and the ID for the LTM candidate cell configuration.

Fig. 11 illustrates a flowchart of a method 1100 that supports LTM in accordance with aspects of the present disclosure. The operations of the method 1100 may be implemented by a device or its components as described herein. For example, the operations of the method 1100 may be performed by a first network node as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1110, the method may include receiving, from a second network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The operations of 1110 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1110 may be performed by a device as described with reference to Fig. 2A or 2B.

At 1120, the method may include determining, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource. The operations of 1120 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1120 may be performed by a device as described with reference to Fig. 2A or 2B.

At 1130, the method may include determining a first CGI for the target LTM cell based on first association between the first PCI and the first CGI. The operations of 1130 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1130 may be performed by a device as described with reference to Fig. 2A or 2B.

Fig. 12 illustrates a flowchart of a method 1200 that supports LTM in accordance with aspects of the present disclosure. The operations of the method 1200 may be implemented by a device or its components as described herein. For example, the operations of the method 1200 may be performed by a second network node as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1210, the method may include transmitting, to a first network node, a CSI resource configuration for LTM of a UE, wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an ID for one of the at least one LTM candidate cell configuration and with a PCI for one of at least one LTM candidate cell. The operations of 1210 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1210 may be performed by a device as described with reference to Fig. 2A or 2B.

At 1220, the method may include transmitting, to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell. The operations of 1220 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1220 may be performed by a device as described with reference to Fig. 2A or 2B.

Fig. 13 illustrates a flowchart of a method 1300 that supports LTM in accordance with aspects of the present disclosure. The operations of the method 1300 may be implemented by a device or its components as described herein. For example, the operations of the method 1300 may be performed by a UE 104 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1310, the method may include receiving an RRC reconfiguration message from a first network node, wherein the RRC reconfiguration message comprises a CSI resource configuration for LTM of a UE, the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an ID for one of the at least one LTM candidate cell configuration and a PCI for one of the at least one LTM candidate cell. The operations of 1310 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1310 may be performed by a device as described with reference to Fig. 1, 2A or 2B.

At 1320, the method may include transmitting an RRC reconfiguration complete message to the first network node. The operations of 1320 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1320 may be performed by a device as described with reference to Fig. 1, 2A or 2B.

Fig. 14 illustrates a flowchart of a method 1400 that supports LTM in accordance with aspects of the present disclosure. The operations of the method 1400 may be implemented by a device or its components as described herein. For example, the operations of the method 1400 may be performed by a first network node as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1410, the method may include transmitting, to a UE, a cell change command for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration. The operations of 1410 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1410 may be performed by a device as described with reference to Fig. 2A or 2B.

At 1420, the method may include transmitting, to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration. The operations of 1420 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1420 may be performed by a device as described with reference to Fig. 2A or 2B.

Fig. 15 illustrates a flowchart of a method 1500 that supports LTM in accordance with aspects of the present disclosure. The operations of the method 1500 may be implemented by a device or its components as described herein. For example, the operations of the method 1500 may be performed by a second network node as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1510, the method may include receiving, from a first network node, a cell change notification for LTM, wherein the cell change command for LTM comprises an ID for an LTM candidate cell configuration. The operations of 1510 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1510 may be performed by a device as described with reference to Fig. 2A or 2B.

At 1520, the method may include determining a first CGI for a target LTM cell based on association between the first CGI and the ID for the LTM candidate cell configuration. The operations of 1520 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1520 may be performed by a device as described with reference to Fig. 2A or 2B.

It shall be noted that implementations of the present disclosure which have been described with reference to Figs. 1 to 8 are also applicable to the device 900, the processor 1000 as well as the methods 1100, 1200, 1300, 1400 and 1500.

It should be noted that the methods described herein describes possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

As used herein, including in the claims, an article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A first network node, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive, via the transceiver from a second network node, a channel state information (CSI) resource configuration for layer 1 or layer 2 triggered mobility (LTM) of a user equipment (UE) , wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an identifier (ID) for one of the at least one LTM candidate cell configuration and with a physical cell identifier (PCI) for one of at least one LTM candidate cell;

determine, based on a layer 1 measurement report from the UE, a first PCI for a target LTM cell which is one of the at least one LTM candidate cell, wherein the layer 1 measurement report comprises at least one measurement result for the at least one first CSI resource; and

determine a first cell global identifier (CGI) for the target LTM cell based on first association between the first PCI and the first CGI.
The first network node of claim 1, wherein the processor is further configured to:

obtain information related to at least one association, wherein each of the at least one association is between the PCI and a CGI for one of the at least one LTM candidate cell, the at least one association comprises the first association between the first PCI and the first CGI.
The first network node of claim 2, wherein the processor is configured to obtain the information related to the at least one association by:

obtaining a neighbour cell relation table, wherein each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell, the at least one LTM candidate cell is configured as the at least one neighbour cell.
The first network node of claim 3, wherein the processor is configured to obtain the neighbour cell relation table from operations administration and maintenance (OAM) or the second network node.
The first network node of claim 2, wherein the processor is configured to obtain the information related to the at least one association from operations administration and maintenance (OAM) .
The first network node of claim 2, wherein the processor is configured to obtain the information related to the at least one association from the second network node.
The first network node of claim 2, wherein the CSI resource configuration for LTM comprises the information related to the at least one association.
The first network node of claim 1, wherein the processor is further configured to:

receive a radio resource control (RRC) reconfiguration message via the transceiver from the second network node, wherein the RRC reconfiguration message comprises the CSI resource configuration for LTM; and

forward the RRC reconfiguration message via the transceiver to the UE.
The first network node of claim 7 or 8, wherein each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is further associated with the CGI for one of the at least one LTM candidate cell.
The first network node of claim 1, wherein the processor is further configured to:

receive, via the transceiver from the second network node, at least one reference signal (RS) configuration for the at least one LTM candidate cell, wherein each of the at least one RS configuration includes at least one second CSI resource and the PCI for one of the at least one LTM candidate cell, and the at least one second CSI resource includes the at least one first CSI resource.
A second network node, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

transmit, via the transceiver to a first network node, a channel state information (CSI) resource configuration for layer 1 or layer 2 triggered mobility (LTM) of a user equipment (UE) , wherein the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with an identifier (ID) for one of the at least one LTM candidate cell configuration and with a physical cell identifier (PCI) for one of at least one LTM candidate cell; and

transmit, via the transceiver to the first network node, information related to at least one association, wherein each of the at least one association is between the PCI and a cell global identifier (CGI) for one of the at least one LTM candidate cell.
The second network node of claim 11, wherein the processor is further configured to:

obtain the information related to the at least one association from operations administration and maintenance (OAM) or a third network node providing the at least one LTM candidate cell.
The second network node of claim 11, wherein the processor is configured to transmit the information related to the at least one association by:

transmitting a neighbour cell relation table, wherein each of entries of the neighbour cell relation table comprises the PCI and the CGI of one of at least one neighbour cell, the at least one LTM candidate cell is configured as the at least one neighbour cell.
The second network node of claim 11, wherein the CSI resource configuration for LTM comprises the information related to the at least one association.
The second network node of claim 11, wherein the processor is further configured to:

transmit a radio resource control (RRC) reconfiguration message via the transceiver to the first network node, wherein the RRC reconfiguration message comprises the CSI resource configuration for LTM.
The second network node of claim 14 or 15, wherein each of the at least one first CSI resource indicated in the CSI resource configuration for LTM is further associated with the CGI for one of the at least one LTM candidate cell.
The second network node of claim 11, wherein the processor is further configured to:

transmit, via the transceiver to the first network node, at least one reference signal (RS) configuration for the at least one LTM candidate cell, wherein each of the at least one RS configuration includes at least one second CSI resource and the PCI for one of the at least one LTM candidate cell, and the at least one second CSI resource includes the at least one first CSI resource.
A user equipment (UE) , comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive a radio resource control (RRC) reconfiguration message via the transceiver from a first network node, wherein the RRC reconfiguration message comprises a channel state information (CSI) resource configuration for layer 1 or layer 2 triggered mobility (LTM) of a user equipment (UE) , the CSI resource configuration for LTM indicates at least one first CSI resource for at least one LTM candidate cell configuration, each of the at least one first CSI resource is associated with the following: an identifier (ID) for one of the at least one LTM candidate cell configuration and a physical cell identifier (PCI) for one of the at least one LTM candidate cell; and

transmit an RRC reconfiguration complete message via the transceiver to the first network node.
The user equipment of claim 18, wherein each of the at least one first CSI resource is further associated with a cell global identifier (CGI) for one of the at least one LTM candidate cell.
A first network node, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

transmit, via the transceiver to a user equipment (UE) , a cell change command for layer 1 or layer 2 triggered mobility (LTM) , wherein the cell change command for LTM comprises an identifier (ID) for an LTM candidate cell configuration; and

transmit, via the transceiver to a second network node, a cell change notification for LTM, wherein the cell change notification for LTM comprises the ID for the LTM candidate cell configuration.