User equipment, radio network node, and methods performed for signalling cell indications in LTM mobility

Abstract

Embodiments herein relate to, for example, a method performed by a UE (10) for handling a cell switching procedure in a wireless communication network. The UE (10) obtains an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching5 procedure.

Description

[0001] USER EQUIPMENT, RADIO NETWORK NODE, AND METHODS PERFORMED THEREIN

[0002] TECHNICAL FIELD

[0003] Embodiments herein relate to a user equipment (UE), a radio network node, and methods performed therein regarding wireless communication. Furthermore, a computer program product and a computer readable storage medium are also provided herein. In particular, embodiments herein relate to handling communication, such as handling a cell switching procedure, in a wireless communication network.

[0004] BACKGROUND

[0005] In a typical wireless communication network, UEs, also known as wireless communication devices, mobile stations, stations (STA) and / or wireless devices, communicate via a Radio Access Network (RAN) with one or more core networks (CN). The RAN covers a geographical area which is divided into service areas or cells, with each service area or cell being served by a radio network node such as an access node, e.g., a Wi-Fi access point or a radio base station (RBS), which in some networks may also be called, for example, a NodeB, a gNodeB, or an eNodeB. The service area or cell is a geographical area where radio coverage is provided by the radio network node. The radio network node operates on radio frequencies to communicate over an air interface with the UEs within range of the radio network node. The radio network node communicates over a downlink (DL) to the UE and the UE communicates over an uplink (UL) to the radio network node.

[0006] A Universal Mobile Telecommunications System (UMTS) is a third generation (3G) telecommunication network, which evolved from the second generation (2G) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and / or High-Speed Packet Access (HSPA) for communication with user equipment. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for present and future generation networks and investigate e.g. enhanced data rate and radio capacity. In some RANs, e.g. as in UMTS, several radio network nodes may be connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural radio network nodes connected thereto. The RNCs are typically connected to one or more core networks.

[0007] Specifications for the Evolved Packet System (EPS) have been completed within the 3GPP and coming 3GPP releases, such as New Radio (NR), are worked on. The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long-Term Evolution (LTE) radio access network, and the Evolved Packet Core (EPC), also known as SystemArchitecture Evolution (SAE) core network. E-UTRAN / LTE is a 3GPP radio access technology wherein the radio network nodes are directly connected to the EPC core network. As such, the Radio Access Network (RAN) of an EPS has an architecture comprising radio network nodes connected directly to one or more core networks.

[0008] With the emerging 5G technologies such as NR and 6G, the use of very many transmit-and receive-antenna elements may be of great interest as it makes it possible to utilize beamforming, such as transmit-side and receive-side beamforming. Transmit-side beamforming means that the transmitter can amplify the transmitted signals in a selected direction or directions, while suppressing the transmitted signals in other directions. Similarly, on the receive-side, a receiver can amplify signals from a selected direction or directions, while suppressing unwanted signals from other directions. NR is connected to the 5G Core Network (5GC) which comprises a number of Network Functions (NF) such as Session Management Function (SMF), User Plane Function (UPF), Access and Mobility Management Function (AMF), Authentication Service Function (AUSF), Policy Control Function (PCF), Unified Data Manager (UDM), Network Repository Function (NRF), Network Exposure Function (NEF), just to mention some. In the 5GC, NFs can discover other NFs by using a discovery service provided by the NRF.

[0009] Measurements and reporting in 5G NR enable the network to dynamically configure cells in a Master Cell Group (MCG) or a Secondary Cell Group (SCG) for enhancing coverage, capacity, and mobility. The UE performs measurements on neighboring cells, focusing on measurement metrics like reference signal received power (RSRP), reference signal received quality (RSRQ), and / or signal to interference and noise ratio (SINR) to evaluate signal quality and interference levels. These measurements are based on reference signals such as the Synchronization Signal Block (SSB) for initial synchronization and Channel State Information Reference Signals (CSI-RS) for detailed channel state information (CSI). The network uses Radio Resource Control (RRC) signaling to configure the UE with measurement objects and one or more reporting criteria. A measurement object specifies the target frequency of the cells to be measured, cell group information, such as MCG or SCG, reference signal information, such as SSB or CSI-RS, measurement types, e.g., RSRP, RSRQ, or SINR, the UE needs to perform, and / or other relevant neighboring cell information. Reporting configurations define one or more triggering events for sending measurement reporting, which may be event-based, such as using threshold conditions, or periodic, such as performed in regular intervals. For MCG, measurement reports help decide if a neighboring cell should be added as a secondary cell (SCell), improving data rates and / or providing redundancy using carrier aggregation (CA). For SCG, in Dual Connectivity (DC), received reports guide addition of one or more SCG SCells to enhance capacity or offload traffic from an MCG cell or cells.

[0010] The UE sends measurement reports to a Master Node (MN) for MCG SCell measurements or a Secondary Node (SN) for SCG SCell measurements. Upon receiving the measurementreports, the network evaluates signal quality and decides whether to add, modify, or remove SCells based on predefined thresholds and / or resource availability. The network activates SCells using RRC signaling, specifying CA and / or dual connectivity settings for data transmission. Dynamic updates allow the network to deactivate SCells with degrading signal quality or replace the SCells with better-performing neighboring cells. By leveraging UE measurement and reporting, 5G NR achieves efficient resource allocation, improved coverage, and seamless user mobility management.

[0011] Layer 1 and / or Layer 2 (L1 / L2) Triggered Mobility, denoted as LTM, has been introduced as a lower-layer mobility procedure in Release (Rel)-18, enabling a network node to receive measurement reports from a UE via L1 signaling. These L1 -measurement reports are used by the network for mobility-related decisions, such as executing an LTM cell switch to a target cell by sending an LTM Cell Switch Medium Access Control (MAC) Control Element (CE) command. The LTM process is outlined as follows:

[0012] 1. The UE, being in RRC_Connected state, sends one or more layer 3 (L3)-measurement reports to the gNB for one or more cells. Based on these reports, the gNB identifies and configures one or more cells as LTM candidate cells, initiating an LTM preparation phase.

[0013] 2. The gNB performs candidate preparation, and sends an RRC Reconfiguration message to the UE with configuration details for the LTM candidate cells, i.e. , with one or more LTM candidate configurations.

[0014] 3. The UE stores the received one or more LTM candidate configurations and acknowledges with an RRC Reconfiguration Complete message.

[0015] 4. -4a-DL Pre-Synchronization: The UE may perform early DL synchronization with one or more LTM candidate cells upon receiving a Candidate Cell Transmission Configuration Indicator (TCI) States Activation and / or Deactivation MAC CE, reducing the mobility interruption by avoiding SSB-based synchronization after the cell switch.

[0016] -4b-UL Pre-Synchronization: If the UE receives a Physical Downlink Control Channel (PDCCH) order for early Timing Advance (TA) acquisition, the UE may also perform UL pre-synchronization with the one or more LTM candidate cells, further reducing the mobility delay.

[0017] 5. The UE performs L1 measurements on the configured one or more LTM candidate cells and reports the L1 measurements to the gNB, i.e., the source node.

[0018] 6. The source node decides the target cell for the switch and sends an LTM Cell Switch command MAC CE containing the configuration index of the decided or selected LTM cell. The UE switches to the target cell and applies the indicated configuration of the LTM candidate cell. Thus, the UE detaches from source node and applies target configuration or configurations.7. If the UE lacks a valid TA value for the target cell, the UE performs a random-access procedure over a Random Access Channel (RACH). If a valid TA was acquired earlier during early UL synchronization, this procedure is skipped. Moreover, if the target cell TCI state indicated in the LTM cell switch MAC CE differs from the pre-synchronized TCI state, additional synchronization may be required.

[0019] 8. The UE completes the LTM cell switch by sending an RRC Reconfiguration Complete message to the target cell, such as an LTM cell switch completion. For cases involving random-access, successful completion of the random-access procedure confirms the switch. For RACH-less LTM, the switch is deemed successful once the network acknowledges the UE’s first UL data transmission. Fig. 1 depicts the overall procedure for LTM.

[0020] SUMMARY

[0021] As part of developing embodiments herein one or more issues have been identified. During the Rel-18 discussions for LTM, the following was agreed in RAN2:

[0022] RAN2#119-e meeting:

[0023] R2 assumption: Rel-18 L 1 / L2 mobility includes both non-carrier aggregation (CA) (primary cell (PCell) only) and CA scenarios (PCell and SCell). This includes the following cases:

[0024] a) the target PCell and / or target SCell(s) is not a current serving cell (CA -> CA scenario with PCell change)

[0025] b) For further study (FPS) the target PCell is a current SCell

[0026] c) FFS the target SCell is the current PCell.

[0027] RAN2#119bis-e meeting:

[0028] For L 1 / L2 mobility, Target Pcell and / or SCell can be current SCell and / or PCell, i.e., current Seel and / or PCell can be configured as candidates.

[0029] RAN2#123bis meeting:

[0030] Confirm that deactivated SCell as LTM candidate cell is supported

[0031] According to the two agreements cited above, it should be possible when performing an LTM cell switching procedure to handoff the UE to a primary cell (PCell) which is a current SCell and vice versa. Also, there is no limitation that only activated SCells should be part of an LTM candidate cell configuration, but network has the freedom to also include a deactivated SCell. Furthermore, it could be possible with an LTM to do an SCell switch without changing the PCell or primary secondary cell (PSCell).

[0032] However, according to the current signaling, in case the UE performs a cell switch such as an LTM cell switch to a LTM candidate cell which includes only an SCell configuration, there is no support at the moment to indicate to the UE whether the SCell included within the LTM candidateconfiguration should be considered as the new PCell or if one of the current one or more SCells should be switched with the SCell included within the LTM candidate configuration. In particular, the following may happen:

[0033] • A UE in Celli (serving cell) is configured with a PCell and / or PSCell and 1 SCell (SCell ID1) o UE is configured also with an LTM candidate configuration which has only 1 SCell (SCell ID2)

[0034] • Celli sends to the UE an LTM cell switch command to switch to the LTM candidate configuration

[0035] • When switching to the indicated LTM candidate configuration:

[0036] o Should the UE consider the SCell ID2 as the new PCell and / or PSCell? o Should the UE consider to keep its current PCell and switch SCell from current SCell ID1 to SCell ID2?

[0037] At the moment it is unclear what the UE behavior is when the described situation, or a similar cell switching procedure, will occur and there is no signaling supported so that the network can indicate to the UE what to do.

[0038] An object of embodiments herein is to handle communication, such as handling a cell switching procedure, in a wireless communication network in an efficient manner.

[0039] According to an aspect the object is achieved, according to some embodiments herein, by providing a method performed by a UE for handling a cell switching procedure in a wireless communication network. The UE obtains an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, a special cell (SpCell), or an SCell. The candidate cell configuration is to be used in the cell switching procedure.

[0040] According to another aspect the object is achieved, according to some embodiments herein, by providing a method performed by a radio network node, such as gNB, for handling a cell switching procedure of a UE in a wireless communication network. The radio network node transmits an indication to the UE, wherein the indication indicates whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure.

[0041] It is furthermore provided herein a computer program product comprising instructions, which, when executed on at least one processor, cause the at least one processor to carry out the methods herein, as performed by the UE and the radio network node, respectively. It is additionally provided herein a computer-readable storage medium, having stored thereon a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the methods herein, as performed by the UE and the radio network node, respectively.

[0042] According to another aspect the object is achieved by providing a UE, and a radio network node configured to perform the methods herein, respectively.Thus, according to an aspect the object is achieved, according to some embodiments herein, by providing a UE for handling a cell switching procedure in a wireless communication network. The UE is configured to obtain an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCelL The candidate cell configuration is to be used in the cell switching procedure.

[0043] According to another aspect the object is achieved, according to some embodiments herein, by providing a radio network node for handling a cell switching procedure of a UE in a wireless communication network. The radio network node is configured to transmit an indication to the UE, wherein the indication indicates whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCelL The candidate cell configuration is to be used in the cell switching procedure.

[0044] Embodiments herein aim to allow the network such as the radio network node, to clarify how the UE should handle the case where the UE performs a cell switch, such as an LTM cell switch, according to a candidate cell configuration, such as an LTM candidate cell configuration, which include only one or more candidate cells, such as SCells. To allow this, different solutions may be adopted, which may refer to one or more of the following:

[0045] • The radio network node may send the indication to indicate to the UE whether the UE should change the current PCell and / or PSCell with one or more SCells which are within the indicated candidate cell configuration.

[0046] • The radio network node may send the indication to indicate to the UE whether the UE should change (one of) one or more of the current SCells with (one of) one or more of the SCells which are within the indicated candidate cell configuration.

[0047] • If the radio network node wants, upon a cell switch, for the UE to change the current PCell and / or PSCell with (one of) one or more of the SCells which are within the indicated candidate cell configuration, it should include and / or indicate within the candidate cell configuration (one of) one or more of the SCells as a PCell and / or PSCell.

[0048] • If the UE is switched to a candidate cell which has only one or more SCells this is an indication, being an example of the indication, that the UE should either change the current PCell and / or PSCell with (one of) one or more of the SCells which are within the indicated LTM candidate cell configuration or that the UE should change (one of) one or more of the current SCells with (one of) one or more of the SCells which are within the indicated candidate cell configuration.

[0049] The methods and solutions proposed herein aim to allow the radio network node to clarify how the UE should handle the case where the UE performs a cell switch to a candidate cell configuration which include only one or more SCells. This will prevent the UE from declaring a failure or executing a procedure which is not in line with what the radio network node wants. In this case, long delays, connectivity interruptions, and / or signaling overhead may also be reduced oravoided. Thus, embodiments herein handle communication, such as handling a cell switching procedure, in a wireless communication network in an efficient manner.

[0050] BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Embodiments will now be described in more detail in relation to the enclosed drawings, in which: Fig. 1 is a schematic overview depicting a flowchart for performing a cell switch according to prior art;

[0052] Fig. 2 shows an overview depicting a wireless communication network according to embodiments herein;

[0053] Fig. 3 is a combined flowchart and signaling scheme according to some embodiments herein; Fig. 4 is a schematic flowchart depicting a method performed by a UE according to embodiments herein;

[0054] Fig. 5 is a schematic flowchart depicting a method performed by a radio network node according to embodiments herein;

[0055] Fig. 6 shows a block diagram depicting embodiments of a UE according to embodiments herein; Fig. 7 shows a block diagram depicting embodiments of a radio network node according to embodiments herein;

[0056] Fig. 8 shows an example of a communication system 15100 in accordance with some embodiments;

[0057] Fig. 9 shows a communication system 15200 in accordance with some embodiments;

[0058] Fig. 10 shows a UE 15300 in accordance with some embodiments;

[0059] Fig. 11 is a block diagram of a network node 15400 in accordance with various aspects described herein; and

[0060] Fig. 12 is a block diagram illustrating a virtualization environment 15500 in which functions implemented by some embodiments may be virtualized.

[0061] DETAILED DESCRIPTION

[0062] Embodiments herein relate to wireless communication networks in general. Fig. 2 is a schematic overview depicting a wireless communication network 1. The wireless communication network 1 comprises one or more RANs and one or more CNs. The wireless communication network 1 may use one or a number of different technologies. Embodiments herein relate to recent technology trends that are of particular interest in a New Radio (NR) context, however, embodiments are also applicable in further development of existing wireless communications systems such as e.g. LTE or Wideband Code Division Multiple Access (WCDMA), or upcoming systems such as 6G etc.

[0063] In the wireless communication network 1 , one or more UEs such as a user equipment (UE) 10 exemplified herein as a wireless device such as a mobile station, a non-access point (non-AP) station (STA), a STA and / or a wireless terminal, are comprised communicating via e.g. one or more Access Networks (AN), e.g. radio access network (RAN), to one or more core networks (CN). It should be understood by the skilled in the art that “UE” is a non-limiting term which means any terminal, wireless communications terminal, user equipment, narrowband internet of things (NB-loT) device, Machine Type Communication (MTC) device, Device to Device (D2D) terminal, or node e.g. smart phone, vehicle, smart glasses, smart watch, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station capable of communicating using radio communication with a radio network node within an area served by the radio network node.

[0064] The wireless communication network 1 comprises a first radio network node 12, providing radio coverage over a geographical area, a first service area 11 or first cell, of a first radio access technology (RAT), such as 6G, NR, LTE, or similar. The first radio network node 12 may be a transmission and reception point such as an access node, an access controller, a base station, A Next Generation Radio Access Network (NG-RAN) node, e.g. a radio base station such as a gNodeB (gNB), an evolved Node B (eNB, eNode B), a NodeB, a base transceiver station, a radio remote unit, an Access Point Base Station, a Central unit (CU) node, base station router, a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node capable of communicating with a UE within the area served by the first radio network node depending e.g. on the first radio access technology and terminology used. The first radio network node 12 may be referred to as a primary node, or primary radio network node wherein the service area may be referred to as a primary cell and / or as primary secondary cell, and the primary node communicates with the UE 10 in form of DL transmissions to the UE 10 and UL transmissions from the UE 10. It should be noted that a service area may be denoted as cell, beam, beam group or similar to define an area of radio coverage.

[0065] The wireless communication network 1 comprises a second radio network node 13, providing radio coverage over a geographical area, a second service area 14 or second cell and a third service area 15 or third cell, of a second RAT, such as 6G, NR, LTE, or similar. The second radio network node 13 may be a transmission and reception point such as an access node, an access controller, a base station, e.g. a radio base station such as a gNodeB (gNB), an evolved Node B (eNB, eNode B), a NodeB, a base transceiver station, a radio remote unit, a CU node, an Access Point Base Station, a base station router, a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node capable of communicating with a wireless device within the area served by the second radio network node depending e.g. on the first radio access technology and terminology used. The second radio network node may be referred to as a secondary radio network node or secondary serving radio network node, wherein the service area may be referred to as a secondary cell or secondary serving cell, and the secondradio network node communicates with the UE in form of DL transmissions to the UE 10 and UL transmissions from the UE 10. It should be noted that a service area may be denoted as cell, beam, beam group or similar to define an area of radio coverage.

[0066] The first RAT may be the same RAT as the second RAT or the first RAT may be a different RAT than the second RAT.

[0067] The wireless communication network 1 may further comprise a number of network nodes providing network functions (NF) or actually instantiations of NFs also referred to as NF instances, such as a first network node 16, for example, an AMF. The different NF instances may have different tasks. Other functions may be for LTE such as mobility management entity (MME) or similar.

[0068] The respective node may be a standalone server, a cloud-implemented server, a distributed server or processing resources in a server farm or same node. Embodiments herein may be implemented as physical bare metal, virtual or cloud native such as Kubernetes environment in, e.g., hyper-cloud networks.

[0069] Embodiments herein relate to a UE for handling a cell switching procedure of cells and how the UE 10 obtains information about whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure. The UE 10 may receive an indication indicating the information from a radio network node 120 such as the first radio network node 12 or the second radio network node 13. The cell switching procedure may comprise an LTM mobility procedure.

[0070] The text herein refers to the term LTM, which may also sometimes may be referred to as L1 / L2 based inter-cell mobility, L1 / L2-centric inter-cell mobility, or Lower-layer triggered Mobility (LLM). The basic principle is that the UE 10 receives a lower layer signaling, e.g., a MAC CE, from the network indicating to the UE 10 a change, or switch or activation, of its serving cell, e.g., change of PCell, from a source to a target PCell, wherein a lower layer signaling is a message and / or signaling of a lower layer protocol, which may be referred as a LTM execution command or LTM cell switch command. The change of serving cell, e.g., change of PCell, may also lead to a change in one or more SCells for the same cell group e.g., in case the command triggers the UE 10 to change to another cell group configuration of the same type, e.g., another MCG configuration. The change in cell group configuration may also refer to the switch in a special cell (SpCell), SpCell is a common term for covering both PCell and PScell, activation / deactivation of some of the SCells, and / or addition / modification / release of the SCells in the cell group. Before the UE 10 receives the LTM cell switch command, the UE 10 is configured by the network with one or more LTM candidate cells, e.g., reception of an RRC Reconfiguration message, with at least one LTM candidate cell configuration. A candidate cell configuration may include parameters in the information element (IE) CellGroupConfig per LTM candidate cell and / or an embedded RRC Reconfiguration per LTM candidate cell.The term cell switching procedure or LTM cell switching procedure refers to the process of a UE changing its cell from a source cell to a target cell, which may be called here a candidate cell or a neighboring cell, using LTM. In the context of LTM execution or LTM cell switch, the text may refer to the serving cell before the LTM cell switch as source cell, old source cell, or previous source cell. An LTM cell switching procedure may sometimes also be known as dynamic switch, LTM switch, (LTM) cell switch, (LTM) serving cell change or (LTM) cell change, or LTM execution. Even if the term change of cell is used, that may comprise a change of a whole cell group configuration, which includes a change in the SpCell, e.g., change of PCell or change of PSCell, and a change in SCells of the cell group, e.g., addition, modification and / or release of one or more SCells. The LTM cell switching procedure may be triggered by the UE receiving an LTM cell switch command from the network. The source and target cells in a LTM cell switching procedure may be controlled by the same gNB, which sometimes is referred to as the intra-gNB case, or when the gNB uses a distributed CU and / or distributed unit (DU) RAN architecture, the intra-CU inter-DU case or the intra-CU intra-DU case, depending on whether the cells are controlled by the same DU or different DUs. When the source and target cells in an (LTM) cell switching procedure are controlled by different gNBs, this is sometimes referred to as the inter-gNB case, or inter-CU case, or sometimes known as an inter-CU LTM cell switching procedure.

[0071] The text refers to an LTM candidate cell, which is a cell the UE 10 is configured with when configured with L1 / L2-triggered mobility. That is, a cell the UE 10 can move to in an LTM cell switching procedure, upon reception of an LTM cell switch command. The one or more cells may also be called candidate cell or cells, LTM candidate cells, LTM target cells, candidates, mobility candidates, non-serving cells, additional cells, target candidate cell, target candidate, etc. An LTM candidate cell is a cell the UE performs lower layer measurements on, such as Layer 1 reference signal received power (L1-RSRP) and / or synchronization signal (SS)-RSRP, derived from SSBs and / or CSI-RSs of either the source cell and / or an LTM candidate cell. Lower layer measurements, in this context, are measurements reported to support lower layer procedures like beam management, candidate cell TCI state activation and / or deactivation, early TA acquisition, and link adaptation, and they aren't filtered based on L3 parameters, though there may or may not be some filtering of these measurements based on the other lower layer parameters. Lower layer measurement and reporting may also involve receiving the configuration of the parameters such as one or more event conditions, one or more event identifiers, one or more offsets, one or more thresholds, Reference Signal (RS) type, trigger quantity such as RSRP, RSRQ or SINR, Time-To-Trigger (TTT), and so forth. The UE 10 reports these lower layer measurements and network may take educated decisions on which beam, e.g., TCI state, and / or cell the UE is to be switched to. An LTM candidate cell may be a candidate to be a target PCell or PSCell, or an SCell of a cell group, e.g., MCG SCell.Even if the embodiments are written by considering LTM as example, the methods and solution described may be equally applied without any loss of meaning also to the concept of Conditional LTM (CLTM), which can be viewed as a form of conditional reconfiguration, in which LTM cell switch is triggered in the UE 10 by some other event, such as a condition, e.g., a triggering condition used for conditional configuration. In CLTM, the UE 10 is configured with at least one LTM candidate cell, denoted as a CLTM candidate cell, by receiving an LTM candidate cell configuration, as in legacy LTM, and called herein a Conditional LTM candidate cell configuration, and an associated execution condition, denoted as CLTM execution condition. The evaluation of CLTM execution condition associated to a CLTM candidate cell is performed by the assessment of lower layer measurements, such as L1-RSRP and / or SS-RSRP, derived from SSBs and / or CSI-RSs of either the source cell and / or an LTM candidate cell. Lower layer measurements, in this context, are measurements reported to support lower layer procedures like beam management, candidate cell TCI state activation and / or deactivation, early TA acquisition, and link adaptation, and they aren't filtered based on L3 parameters, though there may or may not be some filtering of these measurements based on the other lower layer parameters. The reception of CLTM execution condition may also involve receiving an indication of the condition and / or configuring it with parameters such as one or more event identifiers, one or more offsets, one or more thresholds, RS type, trigger quantity such as RSRP, RSRQ or SINR, TTT, and so forth.

[0072] In the context of CLTM, the UE 10 relies on evaluating one or two conditions, referred to as CLTM execution conditions, LTM execution conditions, or triggering conditions, or a combination thereof. And, when the one or more conditions for a CLTM candidate cell is(are) fulfilled, the UE 10 performs a cell switch, which may be seen as a kind of LTM execution which is not triggered by the reception of an LTM cell switch command. This may also be considered as a kind of LTM cell switch, or LTM cell switch execution, or Conditional LTM cell switch, or Conditional LTM execution, or CLTM execution, or simply cell switch. According to the methods outlined herein, upon satisfaction of the execution condition(s), the UE 10 may initiate an LTM cell switch. The term LTM cell switch refers to the process of a UE changing its cell from a source cell to a target cell, using LTM. In the context of Conditional LTM execution, the text may refer to the serving cell before the LTM cell switch as source cell, old source cell, or previous source cell.

[0073] The text also discusses the concept of an LTM candidate cell within the framework of Conditional LTM. The candidate cell may be referred to as a CLTM candidate cell, CLTM cell, simply candidate cell, candidate target cell, simply target cell, LTM candidate cell, LTM cell, or L1 / L2 inter-cell mobility candidate cell, depending on the context or terminology used herein.

[0074] Essentially, it denotes a cell to which the UE is directed or switches to in the event of executing a conditional L1 / L2 inter-cell mobility procedure after meeting the associated one or more execution conditions and may also be termed as new source cell or next source cell after the LTM cell switch, or after LTM cell switch execution. These cells may also be termed as candidate cells, mobilitycandidates, non-serving cells, additional cells, candidate target cell, simply target cell, and / or deactivated cells. In the context of embodiments herein, performing the CLTM execution comprises the UE 10 considering that the CLTM candidate cell becomes its new special cell or serving primary cell (SpCell) e.g., PCell in case of CLTM being configured for a Master Cell Group (MCG) and / or PSCell in case of CLTM being configured for a Secondary Cell Group (SCG); or, changing its SpCell from the current PCell to a CLTM candidate cell.

[0075] An LTM candidate cell might also pertain to a candidate cell in a 5G Radio Access Technology like NR or a future 6G Radio Access Technology.

[0076] An LTM cell switching procedure may alternatively be triggered in the UE upon the reception of LTM cell switch or by some other event, e.g., an event condition evaluated on L3-RSRP for conditional configuration, such as conditional handover, being fulfilled, as a result of recovery from radio link failure or handover failure.

[0077] The text uses the term “cell” to identify a location, or coverage, on which the UE 10 is located. However, the term “cell” can also be exchanged without any loss of meaning with the terms “radio resources”, “beams”, “TCI state”, or “Tracking Reference Signal (TRS)”. This is just to clarify that embodiments herein do not target specifically a scenario where there is a cell, but rather when a UE uses a set of source radio resources and needs to switch to a target set of radio resources. In such a case, radio resources can also identify a set of configurations, field, parameters, or ASN.1 structures or lEs.

[0078] The text further uses the term MCG to identify a first network entity that provides a first connectivity link to the UE 10 and SCG to identify a second network entity that provides a second connectivity link to the UE 10. However, the terms “MCG” and “MN” can be exchanged without any loss of meaning as well as the terms “SCG” and “SN”. Moreover, the text uses the terms “first radio network node” and “second radio network node” to refer to a source cell, serving cell, source gNB-DU, and / or source DU (S-DU), and an LTM target cell, candidate gNB-DU, and / or candidate DU (C-DU), respectively.

[0079] Examples of radio network nodes, or network nodes, are NodeB, base station (BS), multistandard radio (MSR) radio node such as MSR BS, eNodeB, gNodeB, MeNB, SeNB, location measurement unit (LMU), integrated access backhaul (IAB) node, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), Central Unit e.g. in a gNB, Distributed Unit e.g. in a gNB, Baseband Unit, Centralized Baseband, centralized RAN (C-RAN), access point (AP), transmission points, transmission nodes, transmission reception point (TRP), Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node, e.g. Mobile Switching Center (MSC), MME etc, operation and maintenance (O&M), Operation Support Systems (OSS), Self-Organizing Networks (SON), positioning node, e.g. Evolved-Serving Mobile Location Center (E-SMLC), or the like.The non-limiting term UE refers to any type of wireless device communicating with a network node and / or with another UE in a cellular or mobile communication system. Examples of the UE 10 are target device, device to device (D2D) UE, Internet of Things (loT) capable device, vehicular to vehicular (V2V), machine type UE, machine type communication (MTC) UE or UE capable of machine to machine (M2M) communication, PDA, tablet, smartwatch, smart glasses, mobile terminals, smart phone, laptop embedded equipment (LEE), laptop mounted equipment (LME), universal serial bus (USB) dongles etc.

[0080] The term radio access technology, or RAT, may refer to any RAT e.g. UTRA, E-UTRA, narrow band internet of things (NB-loT), WiFi, Bluetooth, next generation RAT, New Radio (NR), 4G, 5G, 6G etc. Any of the equipment denoted by the term node, network node or radio network node may be capable of supporting a single or multiple RATs.

[0081] The term signal or radio signal used herein can be any physical signal or physical channel. Examples of DL physical signals are RSs, such as primary synchronization signal (PSS), secondary synchronization signal (SSS), CSI-RS, demodulation reference signal (DMRS) in synchronization signal (SS) and / or physical broadcast channel (PBCH) block, also referred to as SSB, discovery reference signal (DRS), Cell RS, positioning reference signal (PRS) etc. RS may be periodic e.g. RS occasion carrying one or more RSs may occur with a certain periodicity e.g. 20 ms, 40 ms etc. The RS may also be aperiodic. Each SSB carries NR-PSS, NR-SSS and NR-PBCH in 4 successive symbols. One or multiple SSBs are transmitted in one SSB burst which is repeated with certain periodicity e.g. 5 ms, 10 ms, 20 ms, 40 ms, 80 ms and 160 ms. The UE is configured with information about SSB on cells of a certain carrier frequency by one or more SS / PBCH block measurement timing configuration (SMTC) configurations. The SMTC configuration comprises parameters such as SMTC periodicity, SMTC occasion length in time or duration, SMTC time offset with regards to reference time, e.g., serving cell’s system frame number (SEN), etc.

[0082] Therefore, SMTC occasion may also occur with certain periodicity, e.g., 5 ms, 10 ms, 20 ms, 40 ms, 80 ms and 160 ms. Examples of UL physical signals are reference signals such as SRS, DMRS etc. The term physical channel refers to any channel carrying higher layer information e.g. data, control etc. Examples of physical channels are PBCH, NPBCH, PDCCH, physical downlink shared channel (PDSCH), short Physical Uplink Control Channel (sPUCCH), sPDSCH, sPUCCH, sPUSCH, MTC physical downlink control channel (MPDCCH), narrowband PDCCH (NPDCCH), NPDSCH, Enhanced-PDCCH, physical uplink shared channel (PUSCH), Physical Uplink Control Channel (PUCCH), NPUSCH etc.

[0083] The term time resource used herein may correspond to any type of physical resource or radio resource expressed in terms of length of time. Examples of time resources are: symbol, time slot, subframe, radio frame, transmission time interval (TTI), interleaving time, slot, sub-slot, minislot, system frame number (SFN) cycle, hyper-SFN (H-SFN) cycle etc.An example scenario which is considered in embodiments herein is the following:

[0084] • The UE 10 is operating in Celli and is configured with a PCell and / or PSCell, such as serving cell 11 , and one SCell, such as SCell 14 ID1.

[0085] o The UE 10 is configured also with an LTM candidate cell configuration with has only 1 SCell ID2, such as cell 15.

[0086] • Celli sends to the UE 10 an LTM cell switch command to switch to the LTM candidate configuration

[0087] • When switching to the indicated LTM candidate configuration:

[0088] o Should the UE 10 consider the SCell ID2 as a new PCell and / or / PSCell? o Should the UE 10 consider to keep its current PCell (Celli) and switch from current SCell ID1 to SCell ID2?

[0089] According to embodiments herein, the UE 10 obtains an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure. As an example, the radio network node 120 may indicate to the UE 10, when performing an LTM cell switch to an LTM candidate cell which has at least an SCell configured, whether to consider the SCell within the LTM candidate cell configuration as the new PCell or whether to consider the SCell within the LTM candidate configuration as a new SCell. The indication may, thus, indicate whether a cell in candidate cell configuration, which candidate cell configuration is to be used in the cell switching procedure, is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell.

[0090] If the SCell within the LTM candidate configuration should be considered as a new SCell, in a further embodiment the radio network node 120 may indicate what are the actions to be performed with the new SCell. The indication may thus further indicate action and / or a role associated with the candidate cell. In particular, one or more of the following may be indicated:

[0091] • Change one of the serving SCells with the candidate cell (the new SCell)

[0092] • Add the candidate cell as an additional serving SCell

[0093] • Release all the serving SCells and configure only the candidate cell as the serving SCell.

[0094] • Modify one of the serving SCells with the configuration of the candidate cell.

[0095] In this case, if more than one SCell is configured within the LTM candidate cell configuration, in another embodiment the network indicates to the UE 10 specifically, when performing an LTM cell switching procedure, which one, i.e. , which candidate cell, should be the new PCell or a new SCell. In this case, the indication may indicate which SCell should be considered as the new PCell and which other SCell should be considered as a new SCell. For instance, if the UE 10 has a PCell and an SCell ID2 configured in the serving cell and if the LTM candidate cell configuration has SCells: SCell ID1, SCell ID2, and SCell ID3, the radio network node 120 may indicate the following to the UE 10, in case the UE 10 switches to the LTM candidate cell configuration:• SCell ID1 should be considered as a new PCell in the (new) serving cell

[0096] • SCell ID1 should be considered as a new SCell ID1 in the (new) serving cell

[0097] • SCell ID2 should be modified with the configuration of SCell ID2, within the LTM candidate cell configuration, in the (new) serving cell, and / or

[0098] • SCell ID3 should be added as a new SCell ID3 in the (new) serving cell.

[0099] The radio network node 120 may indicate to the UE 10 how to handle the one or more SCells within an LTM candidate cell configuration during an LTM cell switching procedure and this indication is only valid for the next (one) LTM cell switching procedure performed by the UE 10 or is valid for all the LTM cell switching procedures performed, unless the radio network node 120 sends a new indication to the UE 10.

[0100] The indication from the radio network node 120 to the UE 10 on how to handle the SCell or SCells within an LTM candidate cell configuration during an LTM cell switching procedure may be specific for an LTM candidate cell configuration or may be common for all configured LTM candidate cell configurations. This is the case where the UE 10 is configured with more than one LTM candidate cell configuration and the radio network node 120 may want to differentiate on how the UE 10 needs to handle the one or more SCells within an LTM candidate cell configuration during an LTM cell switching procedure based on the LTM candidate cell configuration that is applied.

[0101] It may be specified (hard-coded) in a specification how the UE 10 may need to handle the one or more SCells within an LTM candidate cell configuration during an LTM cell switching procedure. For instance, if the UE 10 performs an LTM cell switch to an LTM candidate cell which has only one SCell configured, the UE 10 always considers this SCell as the new PCell in the (new) serving cell. Or also the other way may be true, in an alternative embodiment, if the UE 10 performs an LTM cell switch to an LTM candidate cell which has only one SCell configured, the UE always consider this SCell as the new SCell in the (new) serving cell. Thus, the UE 10 may obtain the indication locally as specified in the specification.

[0102] If the UE 10 performs an LTM cell switch, whether to consider the SCell of the LTM candidate cell configuration as the new PCell or the new SCell in the (new) serving cell is enforced by the configuration, which may be provided within the LTM candidate cell configuration itself. For instance, if the radio network node 120 wants the UE 10 when performing an LTM cell switch to consider the SCell within the LTM candidate cell configuration as the new PCell, it will configure the SCell as an SCell, e.g., within the field sCellToAddModList of CellGroupConfig IE in TS 38.331 v. 18.4.0, but also as a PCell, e.g., within the field spCellConfig of CellGroupConfig IE in TS 38.331 v. 18.4.0. Alternatively, the radio network node 120 may configure the SCell only as a PCell, e.g., within the field spCellConfig of CellGroupConfig IE in TS 38.331 v.18.4.0. In another option, the radio network node 120 may include the current PCell (of the serving cell) of the UE 10 within a configuration which is common to all the configured LTM candidate cell configurations, e.g., a socalled Reference Configuration, and the Reference Configuration may include only an SCell with an LTM candidate cell configuration. This means that when the UE 10 is to perform an LTM cell switching procedure, the UE 10 will apply the PCell from the reference configuration and the SCell from the indicated LTM candidate cell configuration.

[0103] In one embodiment, the SCell included within the LTM candidate cell configuration may be one or more of the following:

[0104] • A totally new SCell e.g., meaning that a physical cell identity (PCI) of the SCell within the LTM candidate cell is different from any PCI of the PCell and SCells which the UE 10 is configured in the serving cell. For instance, the SCell within the LTM candidate cell configuration as PCI 1 and in the serving cell the UE 10 has a PCell with PCI 10 and an SCell with PCI 3.

[0105] • The PCell in the serving cell e.g., meaning that the PCI of the SCell within the LTM candidate cell is the same as the PCI of the PCell which the UE 10 is configured in the serving cell. For instance, the SCell within the LTM candidate cell configuration as PCI 1 and in the serving cell the UE 10 has a PCell with PCI 1 and an SCell with PCI 3.

[0106] • One of the SCell in the serving cell e.g., meaning that the PCI of the SCell within the LTM candidate cell is the same as the PCI of one of the SCells which the UE 10 is configured in the serving cell. For instance, the SCell within the LTM candidate cell configuration as PCI 3 and in the serving cell the UE 10 has a PCell with PCI 10 and an SCell with PCI 3.

[0107] How the radio network node 120 indicates to the UE 10, when performing an LTM cell switch to an LTM candidate cell which has at least an SCell configured, whether to consider the SCell within the LTM candidate cell configuration as the new PCell or whether to consider the SCell within the LTM candidate cell configuration as a new SCell is preconfigured within the LTM candidate cell configuration or is an indication which is included within the LTM cell switch command from the radio network node 120. In particular, the radio network node 120 may include the indication within the LTM candidate cell configuration, and this means that the indication would be pre-configured in RRC, so the indication is static, and the UE 10 may apply the same logic every time that applies the LTM candidate cell configuration. Alternatively, or additionally, the radio network node 120 may include the indication within the LTM cell switch command, e.g., in a MAC CE, and this means that the radio network node 120 may indicate something different at every LTM cell switch, since in this case the indication is dynamic.

[0108] It should be noted that embodiments herein may be applied for the PCell and may also be applied equally to the PSCell or SpCelL Further, embodiments herein may apply equally whether the LTM candidate configuration is configured at the MCG or the SCG. Embodiments herein are described for LTM but applies equally also for other cell switching such as CLTM and any other feature which configure candidate cell configurations at the UE 10.Fig.3 is combined flowchart and signaling scheme according to some embodiments herein.

[0109] Action 301. The radio network node 120, such as the second radio network node 13 or first radio network node 12, may transmit a configuration indication. The configuration indication may comprise a configuration or similar. The radio network node 120 may thus configure the UE 10 with the candidate cell configuration comprising one or more candidate cells such as SCells or similar. The candidate cell configuration may comprise an LTM candidate cell configuration.

[0110] Action 302. A mobility event may be triggered or initiated. This may be based on signal strength of one or more candidate cells and the serving cell.

[0111] Action 303. The radio network node 120 may transmit a switch command to the UE 10. According to some embodiments, the radio network node 120 may transmit the indication to the UE 10, wherein the indication indicates whether a candidate cell in candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell or an SCell. The indication may further indicate action and / or role associated with the candidate cell. The indication may be comprised in the switch command to the UE 10, or the indication may be comprised in the candidate cell configuration sent in action 301.

[0112] Action 304. The UE 10 may then perform cell switching procedure based on the indication, taking the indication into account, or using the indication.

[0113] The method actions performed by the UE 10 for handling the cell switching procedure in the wireless communication network according to embodiments herein will now be described with reference to a flowchart depicted in Fig.4. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes.

[0114] Action 401. The UE 10 may be configured or preconfigured with a candidate cell configuration comprising one or more SCells or similar. The candidate cell configuration may comprise an LTM candidate configuration. The UE 10 may receive the candidate cell configuration from the radio network node 120. The UE 10 may receive an RRC Reconfiguration message from the radio network node 120 with the configuration details for the LTM candidate cells.

[0115] Action 402. The UE 10 may store the received candidate cell configuration such as the LTM candidate cell configuration, and may acknowledge with a confirmation message such as with an RRC Reconfiguration Complete message.

[0116] Action 403. The UE 10 may perform a pre-synchronization with one or more candidate cells in the candidate cell configuration for reducing the mobility delay.

[0117] Action 404. The UE 10 may trigger or initiate the cell switching procedure. As an example, the UE 10 may perform L1 measurements on one or more candidate cells and may report them to the radio network node 120.Action 405. The UE 10 obtains the indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure. The indication may further indicate an action and / or a role associated with the candidate cell. The indication may be comprised in the switch command from the radio network node 120, or the indication may be comprised in the candidate cell configuration in action 401. Furthermore, the UE 10 may be preconfigured with the indication and may obtain it locally from a memory or the like. The indication may indicate that the UE 10 should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

[0118] Action 406. The UE 10 may perform the cell switching procedure based on the indication, taking the indication into account, or using the indication. The cell switching procedure may be related to an LTM procedure. For example, the UE 10 may switch to the target cell and apply the indicated configuration of the LTM candidate cell. For example, the UE 10 may use the candidate cell as a PCell, an SpCell, a PScell or an SCell as indicated by the indication. If the UE 10 lacks a valid TA value for the target cell, it may perform a random-access procedure to the target cell.

[0119] The method actions performed by the radio network node 120 for handling the cell switching procedure of the UE 10 in the wireless communication network according to embodiments herein will now be described with reference to a flowchart depicted in Fig.5. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes.

[0120] Action 501. The radio network node 120 may transmit the configuration indication to the UE 10. The configuration indication may comprise a configuration or similar. The radio network node 12 may thus configure the UE 10 with the candidate cell configuration comprising one or more SCells or similar. The candidate cell configuration may comprise an LTM candidate cell configuration. The radio network node 120 may select one or more candidate cells based on measurements from the UE 10. The radio network node 120 may send an RRC Reconfiguration message to the UE with the configuration details for the LTM candidate cells.

[0121] Action 502. The radio network node 120 may receive one or more measurement reports such as L1 measurements reports from the UE 10.

[0122] Action 503. The radio network node 120 may select or determine the target cell for the switch.

[0123] Action 504. The radio network node 120 transmits the indication to the UE 10, wherein the indication indicates whether the candidate cell in the candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure. The indication may further indicate the action and / or the roleassociated with the candidate cell. The indication may be comprised in the switch command to the UE 10, or the indication may be comprised in the candidate cell configuration sent in action 501. The cell switching procedure may be related to an LTM procedure. In some embodiments, the radio network node 120 sends an “LTM Cell Switch” command MAC CE containing a configuration index of the selected LTM cell. The indication may indicate that the UE 10 should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

[0124] Fig.6 is a block diagram depicting the UE 10 for handling the cell switching procedure in the wireless communication network 1 according to embodiments herein.

[0125] The UE 10 may comprise processing circuitry 601 , e.g., one or more processors, configured to perform the methods herein.

[0126] The UE 10 and / or the processing circuitry 601 is configured to obtain the indication indicating whether the candidate cell in the candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCelL The candidate cell configuration is to be used in the cell switching procedure,

[0127] The indication may further indicate the action and / or the role associated with the candidate cell.

[0128] The indication may be comprised in the switch command from the radio network node, or the indication may be comprised in a candidate cell configuration from the radio network node, or the UE may be preconfigured with the indication and obtains it locally from a memory.

[0129] The indication may indicate that the UE 10 should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

[0130] The UE 10 and / or the processing circuitry 601 may be configured to perform the cell switching procedure based on the indication, taking the indication into account, or using the indication.

[0131] The cell switching procedure may be related to an LTM procedure.

[0132] The UE 10 may comprise a memory 605. The memory 605 comprises one or more units to be used to store data on, such as data packets, indications, candidate cell configuration, cell information, cell roles, actions, common signal / channel information, reference signal measurement, events and applications to perform the methods disclosed herein when being executed, and similar. Furthermore, the UE 10 may comprise a communication interface 606 such as comprising a transmitter, a receiver, a transceiver and / or one or more antennas.

[0133] The methods according to the embodiments described herein for the UE 10 are respectively implemented by means of e.g. a computer program product 607 or a computer program,comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. The computer program product 607 may be stored on a computer-readable storage medium 608, e.g., a disc, a universal serial bus (USB) stick or similar. The computer-readable storage medium 608, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. In some embodiments, the computer-readable storage medium may be a transitory or a non-transitory computer-readable storage medium. Thus, embodiments herein may disclose the UE for handling the cell switching procedure in a wireless communication network, wherein UE comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said UE is operative to perform any of the methods herein.

[0134] Fig.7 is a block diagram depicting the radio network node 120 for handling the cell switching procedure of the UE in the wireless communication network according to embodiments herein.

[0135] The radio network node 120 may comprise processing circuitry 701 , e.g., one or more processors, configured to perform the methods herein.

[0136] The radio network node 120 and / or the processing circuitry 701 is configured to transmit to the UE, the indication indicating whether the candidate cell in the candidate cell configuration is, or is to be used as, a PCell, a PSCell, an SpCell, or an SCell. The candidate cell configuration is to be used in the cell switching procedure,

[0137] The indication may further indicate the action and / or the role associated with the candidate cell.

[0138] The indication may be comprised in the switch command to the UE 10, or the indication may be comprised in the candidate cell configuration to the UE.

[0139] The cell switching procedure may be related to an LTM procedure. The indication may indicate that the UE 10 should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

[0140] The radio network node 120 may comprise a memory 705. The memory 705 comprises one or more units to be used to store data on, such as data packets, indications, candidate cell configuration, SSB information, common signal / channel information, cell information, candidate cells, reference signal information, assistance information, application information, messages, measurement, events and applications to perform the methods disclosed herein when being executed, and similar. Furthermore, the radio network node 120 may comprise a communicationinterface 706 such as comprising a transmitter, a receiver, a transceiver and / or one or more antennas.

[0141] The methods according to the embodiments described herein for the radio network node 120 are respectively implemented by means of e.g. a computer program product 707 or a computer program, comprising instructions, i.e. , software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node 120. The computer program product 707 may be stored on a computer-readable storage medium 708, e.g., a disc, a USB stick or similar. The computer-readable storage medium 708, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node 120. In some embodiments, the computer-readable storage medium may be a transitory or a non-transitory computer-readable storage medium. Thus, embodiments herein may disclose the radio network node for handling communication in a wireless communication network, wherein radio network node comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said radio network node is operative to perform any of the methods herein.

[0142] In some embodiments a more general term “network node” or “radio network node” is used and it can correspond to any type of radio-network node or any network node, which communicates with a UE and / or with another network node.

[0143] In some embodiments the non-limiting term wireless device or user equipment (UE) is used and it refers to any type of wireless device communicating with a network node and / or with another wireless device in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, proximity capable UE (aka ProSe UE), loT capable device, machine type UE or UE capable of machine to machine (M2M) communication, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles etc.

[0144] Embodiments are applicable to any RAT or multi-RAT systems, where the wireless device receives and / or transmit signals (e.g. data) e.g. NR, Wi-Fi, LTE, LTE-Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications / enhanced Data rate for GSM Evolution (GSM / EDGE), Worldwide Interoperability for Microwave Access (WiMax), or Ultra Mobile Broadband (UMB), just to mention a few possible implementations.

[0145] As will be readily understood by those familiar with communications design, that functions means or circuits may be implemented using digital logic and / or one or more microcontrollers, microprocessors, or other digital hardware. In some embodiments, several or all of the various functions may be implemented together, such as in a single application-specific integrated circuit(ASIC), or in two or more separate devices with appropriate hardware and / or software interfaces between them. Several of the functions may be implemented on a processor shared with other functional components of a wireless device or network node, for example.

[0146] Alternatively, several of the functional elements of the processing means discussed may be provided through the use of dedicated hardware, while others are provided with hardware for executing software, in association with the appropriate software or firmware. Thus, the term “processor” or “controller” as used herein does not exclusively refer to hardware capable of executing software and may implicitly include, without limitation, digital signal processor (DSP) hardware and / or program or application data. Other hardware, conventional and / or custom, may also be included. Designers of communications devices will appreciate the cost, performance, and maintenance trade-offs inherent in these design choices.

[0147] Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and / or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

[0148] Fig.8 shows an example of a communication system 15100 in accordance with some embodiments.

[0149] In the example, the communication system 15100 includes a telecommunications network 15102 that includes an access network 15104, such as a radio access network (RAN), and a core network 15106, which includes one or more core network nodes 15108. The access network 15104 includes one or more access network nodes or base stations of various types, access network nodes 15110A and 15110B are depicted (which may be collectively referred to as network nodes 15110 or radio network node 120), or any other similar 3rdGeneration Partnership Project (3GPP) access nodes or non-3GPP access points (APs). Some embodiments of the access network 15104 may include more than one access network technology. The network nodes 15110 of access network 15104 facilitate direct or indirect connection of wireless devices, also referred to as UEs, such as by connecting UEs 15112A, 15112B, 15112C, and 15112D (one or more of whichmay be generally referred to as UEs 15112 or UE 10) to the core network 15106 over one or more wireless connections.

[0150] Moreover, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunications network 15102 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a network node in the telecommunications network 15102 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other network nodes to implement one or more functionalities of any network node in the telecommunications network 15102, including one or more access network nodes 15110 and / or core network nodes 15108.

[0151] Examples of an ORAN network node include an open radio unit (O-RU), an open distributed unit (O-DU), an open central unit (O-CU), including an O-CU control plane (O-CU-CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). An ORAN network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1 , F1 , W1 , E1 , E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. F1 being an interface between Central Unit and Distributed Unit, and Xn being the interface between base stations. Moreover, an ORAN network node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an O-2 interface defined by the O-RAN Alliance or comparable technologies.

[0152] The network nodes 15110 facilitate direct or indirect connection of one or more UEs 15112 to the core network 15106 over one or more wireless connections. Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 15100 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 15100 may include and / or interface with any type ofcommunication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0153] The UEs 15112 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 15110 and other communication devices. Similarly, the network nodes 15108, 15110 are arranged, capable, configured, and / or operable to communicate directly or indirectly (e.g., via other devices of telecommunications network 15102) with the UEs 15112 and / or with other network nodes or equipment in the telecommunications network 15102 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunications network 15102. More specifically, UEs 15112 may send messages, data, and / or other signals to network nodes 15108, 15110 or other elements of the telecommunications network 15102 by transmitting such signals to the relevant device directly without the signals passing through any intervening devices or by transmitting such signals to the relevant device indirectly through an intervening device (or multiple intervening devices) that then transmit the signal to the relevant device. Similarly, network nodes 15108, 15110 may send messages, data, and other signals to UEs 151122, other network nodes 15108, 15110, and other devices in telecommunications network 15102 directly or indirectly. As one specific example, a core network node 108 may transmit a particular message to a UE 15112 by transmitting the message to an access network node 15110 that will then transmit the message to the intended UE 15112.

[0154] Similarly, a core network node 108 may receive a particular message from a UE 15112 by receiving the message from an access network node 15110 that itself received the message from the UE 15112.

[0155] In the depicted example, the core network 15106 connects elements of the access network 15104 (e.g., one or more of the network nodes 15110) to one or more host computing systems, such as host 15116. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 15106 includes one or more core network nodes (e.g., core network node 15108) of various types, one or more of which may be generally referred to as network nodes 15108.

[0156] Network nodes 15108 are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, access network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 15108. Example core network nodes provide functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier Deconcealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).The host 15116 may be under the ownership or control of a service provider other than an operator or provider of the access network 15104 and / or the telecommunications network 15102. The host 15116 may be operated by the service provider or on behalf of the service provider. The host 15116 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0157] As a whole, the communication system 15100 of Fig. 8 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 15100 may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (Wi-Fi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (Wi-Max), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, Li-Fi, and / or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox. Moreover, the communication system 15100 may be configured to support multiple different standards, protocols, or other rule sets, with individual components supporting all of the relevant rule sets or with different components or sub-systems within the communication system 15100 supporting different standards, protocols, or rule sets.

[0158] As one example, in certain embodiments, access network 15104 may contain some access network nodes 15110 that support 3GPP radio access technologies (RAT), such as LTE or NR, while other access network nodes 15110 support (or the same access network nodes 15110 additionally support) non-3GPP RATs, such as Wi-Fi or a proprietary RAT. As another example, telecommunications network 15102 may support multiple generations of related communication standards (e.g., 4G and 5G 3GPP communication standards) and, as a result, may include an access network 104 and / or a core network 106 that supports multiple different standard generations or may include multiple access networks 104 and / or multiple core networks 106 with individual networks 104, 106 supporting different standard generations.

[0159] Telecommunications network 15102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunications network 15102. For example, the telecommunications network 15102 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband(eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC) / Massive loT services to yet further UEs.

[0160] In some examples, one or more of the UEs 15112 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 15104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 15104. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0161] In the example, the hub 15114 communicates with the access network 15104 to facilitate indirect communication between one or more UEs (e.g., UE 15112C and / or 15112D) and network nodes (e.g., network node 15110B). In some examples, the hub 15114 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 15114 may be a broadband router enabling access to the core network 15106 for the UEs. As another example, the hub 15114 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 15110, or by executable code, script, process, or other instructions in the hub 15114.

[0162] As another example, the hub 15114 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 15114 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 15114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 15114 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 15114 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

[0163] The hub 15114 may have a constant / persistent or intermittent connection to the network node 15110B. The hub 15114 may also allow for a different communication scheme and / or schedule between the hub 15114 and UEs (e.g., UE 15112C and / or 15112D), and between the hub 15114 and the core network 15106. In other examples, the hub 15114 is connected to the core network 15106 and / or one or more UEs via a wired connection. Moreover, the hub 15114 may be configured to connect to an M2M service provider over the access network 15104 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 15110 while still connected via the hub 15114 via a wired or wireless connection. In some embodiments, the hub 15114 may be a dedicated hub - that is, a hub whoseprimary function is to route communications to / from the UEs from / to the network node 15110B. In other embodiments, the hub 15114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 15110B, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0164] Fig.9 is another example of a communication system 15200 according to some embodiments. As used herein, the communication system 15200 includes multiple access points (APs) 15210 (with four exemplary APs 15210A, 15210B, 15210C, and 15210D being depicted) and multiple wireless devices, referred to in the context of communication system 15200 as stations (STAs) 15212 (referred to individually as STA 15212A, STA 15212B, STA 15212C, STA 15212D, and STA 15212E). STA 15212A is served by AP 15210A in a first basic service set (BSS) 15220A. STA 15210B and STA 15210C are served by AP 15210B in a second BSS, BSS 15220B. STA 15212D is served by AP 15210C in a third BSS, BSS 15220C. STA 15212E is served by AP 15210D in a fourth BSS, BSS 15220D. Stations 15212 may be non-AP STAs and correspond to various kinds of wireless devices, for example, user terminals, such as mobile or stationary computing devices like smartphones, laptop computers, desktop computers, tablet computers, gaming devices, head-mounted displays (HMDs) for Augmented Reality (AR) or Virtual Reality (VR), or the like. Further, stations 15212 could, for example, correspond to other kinds of equipment like smart home devices, printers, multimedia devices, data storage devices, or the like.

[0165] Each of STAs 15212 may connect through a radio link to one of APs 15210. For example, depending on location or channel conditions experienced by a given STA 15212, the STA may select an appropriate AP and BSS for establishing the radio link. The radio link may be based on one or more orthogonal frequency-division multiplexing (OFDM) carriers from a frequency spectrum that is shared on the basis of a contention-based mechanism, e.g., an unlicensed or license exempt band like 2.4 GHz Industrial, Scientific, and Medical (ISM) band, the 5 GHz band, the 6 GHz band, or the 60 GHz band.

[0166] Each AP 15210 may provide data connectivity to STAs 15212 connected to a particular AP 15210. As illustrated, APs 15210 may be connected to a data network 15230. In this way, APs 15210 may also provide data connectivity between STAs 15212 and other entities, e.g., to one or more servers, service providers, data sources, data sinks, user terminals, or the like. Accordingly, the radio link established between a given STA 15212 and its serving AP 15210 may be used for providing various kinds of services to STA 15212, e.g., a voice service, a multimedia service, or other data service. Such services may be based on applications that are executed on STA 15212 and / or on a device linked to STA 15212. By way of example, Fig. 9 illustrates an application service platform 15232 provided in data network 15230. The application(s) executed on STA 15212 and / or on one or more other devices linked to STA 15212 may use the radio link for datacommunication with one or more other STA 15212 and / or the application service platform 15232, thereby enabling utilization of the corresponding service(s) at STA 15212.

[0167] Fig. 10 shows a wireless device 15300, being an example of the UE 10, which may be configured to operate in communication system 15100 of Fig. 8 or in communication system 15200 of Fig. 9. The wireless device 15300 may be alternatively referred to as a UE 15300 or the UE 10, like a UE 15112 within the context of communication system 15100, or as a station (STA) 15300 or as a non-access-point station (non-AP STA) 15300, like a STA 15212 within the context of the communication system 15200, in accordance with respective embodiments. As used herein, a wireless device refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other wireless devices. Examples of a wireless device include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle, vehicle-mounted or vehicle embedded / integrated wireless device, and wireless terminal. Other examples include any type of UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-loT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0168] A wireless device 15300 may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, wireless device 15300 may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, wireless device 15300 may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, wireless device 15300 may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0169] In particular embodiments, wireless device 15300 includes processing circuitry 15302 that is operatively coupled via a bus 15304 to an input / output interface 15306, a power source 15308, a memory 15310, a communication interface 15312, and / or any other component, or any combination thereof. Certain embodiments of wireless device 15300 may include all or a subset of the components shown in Fig. 10. The level of integration between the components may vary from one embodiment of wireless device 15300 to another. In general, in a particular embodiment of wireless device 15300, processing circuitry 15302, input / output interface 15306, power source 15308, memory 15310, and communication interface 15312 may, in whole or in part, represent orinclude physical components common to or shared by one or more of the other elements of wireless device 15300. Further, certain embodiments of wireless devices 15300 may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0170] The processing circuitry 15302 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 15310. The processing circuitry 15302 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 15302 may include multiple central processing units (CPUs).

[0171] In the example, the input / output interface 15306 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices.

[0172] Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into wireless device 15300. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

[0173] In some embodiments, the power source 15308 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used to supply power to circuitry or to charge an associated battery. The power source 15308 may further include power circuitry for delivering power from the power source 15308 itself, and / or an external power source, to the various parts of wireless device 15300 via input circuitry or an interface such as an electrical power cable. Power source 15308 may perform any formatting, converting, or other modification to make accessible power suitable for the respective components of the wireless device 15300 to which power is supplied.

[0174] The memory 15310 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasableprogrammable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 15310 includes one or more programs 15314, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 15316. The memory 15310 may store, for use by wireless device 15300, any of a variety of various operating systems or combinations of operating systems.

[0175] The memory 15310 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or IS IM , other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUlCC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 15310 may allow wireless device 15300 to access instructions, programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 15310, which may be or comprise a device-readable storage medium.

[0176] The processing circuitry 15302 may be configured to communicate with an access network or other network via or using the communication interface 15312. The communication interface 15312 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 15322. The communication interface 15312 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another wireless device or a network node in an access network). Each transceiver may include a transmitter 15318 and / or a receiver 15320 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 15318 and receiver 15320 may be coupled to one or more antennas (e.g., antenna 15322) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0177] In the illustrated embodiment, communication functions of the communication interface 15312 may include cellular communication, Wi-Fi communication (e.g., according to an IEEE 802.11 family standard), LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof.Communications may be implemented according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / internet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0178] In particular embodiments, wireless device 15300 may provide an output of data captured via a sensor, through its communication interface 15312, via a wireless connection to a network node, and / or in any appropriate manner. Data captured by sensors of a wireless device 15300 can be communicated through a wireless connection to a network node via another wireless device 15300. In particular embodiments, such output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0179] As another example, wireless device 15300 comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, wireless device 15300 may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

[0180] Wireless device 15300, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. In particular embodiments, wireless device 15300 represents an loT device that comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the example embodiment of wireless device 15300 shown in Fig. 10.As yet another specific example, in an loT scenario, wireless device 15300 may represent a machine or other device that performs monitoring and / or measurements, and transmits the results of such monitoring and / or measurements to another wireless device and / or a network node.

[0181] Wireless device 15300 may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, wireless device 15300 may implement the 3GPP NB-loT standard. In other scenarios, wireless device 15300 may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0182] In practice, any number of wireless devices 15300 may be used together with respect to a single use case. For example, a first wireless device 15300 might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second wireless device 15300 that is a remote controller operating the drone. When a user makes changes from the remote controller, the first wireless device 15300 may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and / or the second wireless device 15300 can also include more than one of the functionalities described above. For example, wireless device 15300 might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

[0183] Fig. 11 shows a network node 15400, being an example of the radio network node 120, in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment, in a telecommunications network. In accordance with respective embodiments, network node 15400 may be configured to operate in communication system 15100 of Fig. 8, like network nodes 15108 or 15110, or in communication system 15200 of Fig. 9, like an AP 15210 or a station 15212. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)), O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU).

[0184] Network nodes 15400 may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. Network node 15400 may be a relay node or a relay donor node controlling a relay. Network nodes 15400 may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node) and / or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts ofa distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0185] Other examples of network nodes 15400 include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, SelfOrganizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0186] In particular embodiments, network node 15400 includes a processing circuitry 15402, a memory 15404, a communication interface 15406, and a power source 15408. In general, in a particular embodiment of network node 15400, processing circuitry 15402, memory 15404, communication interface 15406, and power source 15408 may, in whole or in part, represent or include physical components common to or shared by one or more of the other elements of network node 15400.

[0187] The network node 15400 may be composed of multiple distinct network entities (e.g., a NodeB entity and a RNC entity, or a BTS entity and a BSC entity, etc.), which may each have or utilize their own respective physical components. In certain scenarios in which the network node 15400 comprises multiple such entities (e.g., BTS and BSC), one or more of the separate entities may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 15400 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memories 15404 or portions of memory 15404 for different RATs) and some components may be reused (e.g., a same antenna 15410 may be shared by different RATs). The network node 15400 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 15400, for example GSM, WCDMA, LTE, NR, Wi-Fi (e.g., according to an IEEE 802.11 family standard), Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 15400.

[0188] The processing circuitry 15402 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic operable to provide, either alone or in conjunction with other components, such as the memory 15404, to provide network node 15400 functionality.In some embodiments, the processing circuitry 15402 includes a system on a chip (SOC). In some embodiments, the processing circuitry 15402 includes one or more of radio frequency (RF) transceiver circuitry 15412 and baseband processing circuitry 15414. In some embodiments, the RF transceiver circuitry 15412 and the baseband processing circuitry 15414 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 15412 and baseband processing circuitry 15414 may be on the same chip or set of chips, boards, or units.

[0189] The memory 15404 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or nonvolatile, non-transitory device-readable and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 15402. The memory 15404 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 15402 and utilized by the network node 15400. The memory 15404 may be used to store any calculations made by the processing circuitry 15402 and / or any data received via the communication interface 15406. In some embodiments, the processing circuitry 15402 and memory 15404 is integrated.

[0190] The communication interface 15406 is used in wired or wireless communication of signaling and / or data with UEs, other network nodes, and / or any other network equipment. In the illustrated embodiment, communication interface 15406 comprises port(s) / terminal(s) 15416 to send and receive data, for example to and from a network over a wired connection. In particular embodiments, network node 15300 may be capable of wireless communication and communication interface 15406 may also include radio front-end circuitry 15418 that may be coupled to, or in certain embodiments a part of, an antenna 15410. Particular embodiments of radio front-end circuitry 15418 include filter(s) 15420 and amplifier(s) 15422. The radio front-end circuitry 15418 may be connected to an antenna 15410 and processing circuitry 15402. The radio front-end circuitry may be configured to condition signals communicated between antenna 15410 and processing circuitry 15402. The radio front-end circuitry 15418 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 15418 may convert the digital data into a radio signal(s) having the appropriate channel and bandwidth parameters using a combination of filters 15420 and / or amplifiers 15422. The radio signal(s) may then be transmitted via the antenna 15410. Similarly, when receiving data, the antenna 15410 may collect radio signals which are then converted into digital data by the radio front-end circuitry 15418. The digital data may be passed to the processing circuitry 15402. Inother embodiments, the communication interface may comprise different components and / or different combinations of components.

[0191] In certain alternative embodiments, network node 15400 may be capable of wireless communication but does not include separate radio front-end circuitry 15418, instead, the processing circuitry 15402 includes radio front-end circuitry and is connected to the antenna 15410. Similarly, in some embodiments, all or some of the RF transceiver circuitry 15412 is part of the communication interface 15406. In still other embodiments, the communication interface 15406 includes one or more ports or terminals 15416, the radio front-end circuitry 15418, and the RF transceiver circuitry 15412, as part of a radio unit (not shown), and the communication interface 15406 communicates with the baseband processing circuitry 15414, which is part of a digital unit (not shown).

[0192] The antenna 15410 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 15410 may be coupled to the radio front-end circuitry 15418 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 15410 is separate from the network node 15400 and connectable to the network node 15400 through one or more interfaces or ports.

[0193] The antenna 15410, communication interface 15406, and / or the processing circuitry 15402 may be configured to perform some or all of the receiving operations and / or obtaining operations described herein as being performed by the network node 15400. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment. Similarly, the antenna 15410, the communication interface 15406, and / or the processing circuitry 15402 may be configured to perform some or all of the transmitting or sending operations described herein as being performed by the network node 15400. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment.

[0194] The power source 15408 provides power to the various components of network node 15400 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 15408 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 15400 with power for performing the functionality described herein. For example, the network node 15400 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 15408. As a further example, the power source 15408 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

[0195] Embodiments of the network node 15400 may include additional components beyond those shown in Fig. 11 for providing certain aspects of the network node’s functionality, including any ofthe functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 15400 may include user interface equipment to allow input of information into the network node 15400 and to allow output of information from the network node 15400. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 15400.

[0196] Fig. 12 is a block diagram illustrating a virtualization environment 15500 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 15500 hosted by one or more of hardware nodes, such as a hardware computing device that operates as an access network node, UE, core network node, or host. Further, in embodiments in which a virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment 15500 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an O-2 interface.

[0197] Applications 15502 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and / or benefits of some of the embodiments disclosed herein.

[0198] Hardware 15504 includes processing circuitry, memory that stores software and / or instructions executable by hardware processing circuitry, and / or other hardware devices as described herein, such as a network interface, input / output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 15506 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VM 15508A and VM 15508B (which may be collectively referred to as VMs 15508), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer 15506 may present a virtual operating platform that appears like networking hardware to one or more of the VMs 15508.

[0199] The VMs 15508 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by virtualization layer 15506. Different embodiments of the instance of a virtual appliance 15502 may be implemented on one or more of VMs 15508, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many networkequipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

[0200] In the context of NFV, each of the VMs 15508 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 15508, and that part of hardware 15504 that executes that VM, be it hardware dedicated to that VM and / or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more of the VMs 15508 on top of the hardware 15504 and corresponds to an application 15502.

[0201] Hardware 15504 may be implemented in a standalone network node with generic or specific components. Hardware 15504 may implement some functions via virtualization.

[0202] Alternatively, hardware 15504 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 15510, which, among others, oversees lifecycle management of applications 15502. In some embodiments, hardware 15504 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 15512 which may alternatively be used for communication between hardware nodes and radio units.

[0203] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0204] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

[0205] It will be appreciated that the foregoing description and the accompanying drawings represent non-limiting examples of the methods and apparatus taught herein. As such, the apparatus and techniques taught herein are not limited by the foregoing description and accompanying drawings. Instead, the embodiments herein are limited only by the following claims and their legal equivalents.

[0206] Embodiments:

[0207] A1. A method performed by a UE (10) for handling a cell switching procedure in a wireless communication network, the method comprising:

[0208] obtaining (405) an indication indicating whether a candidate cell in a candidate cell configuration, which candidate cell configuration is to be used in the cell switching procedure, is, or is to be used as, a PCell, PSCell, SpCell, or an SCell

[0209] A2. The method according to A1 wherein the indication further indicates an action and / or role associated with the candidate cell.

[0210] A3. The method according to any of A1-A2, wherein the indication is comprised in a switch command from a radio network node, or the indication is comprised in a candidate cell configuration from the radio network node, or the UE is preconfigured with the indication and obtains it locally from a memory.

[0211] A4. The method according to any of A1-A3, further comprising

[0212] - performing (406) the cell switching procedure based on the indication, taking the indication into account, or using the indication.B1. A method performed by a radio network node (120) for handling a cell switching procedure of a UE in a wireless communication network, the method comprising:

[0213] transmitting (504) to the UE, an indication indicating whether a candidate cell in a candidate cell configuration, which candidate cell configuration is to be used in the cell switching procedure, is, or is to be used as, a PCell, PSCell, SpCell, or an SCell

[0214] B2. The method according to B1 wherein the indication further indicates an action and / or role associated with the candidate cell.

[0215] B3. The method according to any of B1-B2, wherein the indication is comprised in a switch command to the UE, or the indication is comprised in a candidate cell configuration to the UE.

[0216] C1. A computer program product comprising instructions, which, when executed on at least one processor, cause the at least one processor to carry out the method according to any of the embodiments, as performed by the UE and the radio network node, respectively.

[0217] D1. A computer-readable storage medium, having stored thereon a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any of the embodiments, as performed by the UE and the radio network node, respectively.

[0218] E1. A UE (10) for handling a cell switching procedure in a wireless communication network, wherein the UE is configured to:

[0219] obtain an indication indicating whether a candidate cell in a candidate cell configuration, which candidate cell configuration is to be used in the cell switching procedure, is, or is to be used as, a PCell, PSCell, SpCell, or an SCell

[0220] E2. The UE (10) according to E1 wherein the indication further indicates an action and / or role associated with the candidate cell.

[0221] E3. The UE (10) according to any of E1-E2, wherein the indication is comprised in a switch command from a radio network node, or the indication is comprised in a candidate cell configuration from the radio network node, or the UE is preconfigured with the indication and obtains it locally from a memory.E4. The UE according to any of E1-E3, wherein the UE is configured to:

[0222] perform the cell switching procedure based on the indication, taking the indication into account, or using the indication.

[0223] F1. A radio network node (120) for handling a cell switching procedure of a UE in a wireless communication network, wherein the radio network node is configured to: transmit to the UE, an indication indicating whether a candidate cell in a candidate cell configuration, which candidate cell configuration is to be used in the cell switching procedure, is, or is to be used as, a PCell, PSCell, SpCell, or an SCell

[0224] F2. The radio network node (120) according to F1 wherein the indication further indicates an action and / or role associated with the candidate cell.

[0225] F3. The radio network node (120) according to any of F1-F2, wherein the indication is comprised in a switch command to the UE, or the indication is comprised in a candidate cell configuration to the UE.

Claims

CLAIMS1. A method performed by a user equipment, UE, (10) for handling a cell switching procedure in a wireless communication network, the method comprising: obtaining (405) an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a primary cell, PCell, a primary secondary cell, PSCell, a special cell, SpCell, or a secondary cell, SCell, which candidate cell configuration is to be used in the cell switching procedure.

2. The method according to claim 1 , wherein the indication further indicates an action and / or a role associated with the candidate cell.

3. The method according to any of the claims 1-2, wherein the indication is comprised in a switch command from a radio network node (120), or the indication is comprised in a candidate cell configuration from the radio network node (120), or the UE (10) is preconfigured with the indication and obtains it locally from a memory.

4. The method according to any of the claims 1-3, further comprising- performing (406) the cell switching procedure based on the indication, taking the indication into account, or using the indication.

5. The method according to any of the claims 1-4, wherein the indication indicates that the UE should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

6. The method according to any of the claims 1-5, wherein the cell switching procedure is related to a layer one and / or layer two triggered mobility procedure.

7. A method performed by a radio network node (120) for handling a cell switching procedure of a user equipment, UE, (10) in a wireless communication network, the method comprising:transmitting (504) to the UE (10), an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a primary cell, PCell, a primary secondary cell, PSCell, a special cell, SpCell, or a secondary cell, SCell, which candidate cell configuration is to be used in the cell switching procedure.

8. The method according to claim 7, wherein the indication further indicates an action and / or a role associated with the candidate cell.

9. The method according to any of the claims 7-8, wherein the indication is comprised in a switch command to the UE (10), or the indication is comprised in a candidate cell configuration to the UE (10).

10. The method according to any of the claims 7-9, wherein the indication indicates that the UE should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

11. The method according to any of the claims 7-10, wherein the cell switching procedure is related to a layer one and / or layer two triggered mobility procedure.

12. A user equipment, UE, (10) for handling a cell switching procedure in a wireless communication network, wherein the UE (10) is configured to:obtain an indication indicating whether a candidate cell in a candidate cell configuration is, or is to be used as, a primary cell, PCell, a primary secondary cell, PSCell, a special cell, SpCell, or a secondary cell, SCell, which candidate cell configuration is to be used in the cell switching procedure.

13. The UE (10) according to claim 12, wherein the indication further indicates an action and / or a role associated with the candidate cell.

14. The UE (10) according to any of claims 12-13, wherein the indication is comprised in a switch command from a radio network node (120), or the indication is comprised in a candidate cell configuration from the radio network node (120), or the UE (10) is preconfigured with the indication and obtains it locally from a memory.

15. The UE (10) according to any of claims 12-14, wherein the UE (10) is configured to:perform the cell switching procedure based on the indication, taking the indication into account, or using the indication.

16. The UE (10) according to any of the claims 12-15, wherein the indication indicates that the UE should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

17. The UE (10) according to any of the claims 12-16, wherein the cell switching procedure is related to a layer one and / or layer two triggered mobility procedure.

18. A radio network node (120) for handling a cell switching procedure of a user equipment, UE, (10) in a wireless communication network, wherein the radio network node (120) is configured to:transmit to the UE (10), an indication indicating whether a candidate cell in a candidate cell configuration, is, or is to be used as, a primary cell, PCell, a primary secondary cell, PSCell, a special cell, SpCell, or a secondary cell, SCell, which candidate cell configuration is to be used in the cell switching procedure19. The radio network node (120) according to claim 18, wherein the indication further indicates an action and / or a role associated with the candidate cell.

20. The radio network node (120) according to any of claims 18-19, wherein the indication is comprised in a switch command to the UE (10), or the indication is comprised in a candidate cell configuration to the UE (10).

21. The radio network node (120) according to any of the claims 18-20, wherein the indication indicates that the UE should change: a current PCell and / or PSCell with one or more SCells which are within the candidate cell configuration; and / or one or more of current SCells with one or more of the SCells which are within the candidate cell configuration.

22. The radio network node (120) according to any of the claims 18-21 , wherein the cell switching procedure is related to a layer one and / or layer two triggered mobility procedure.

23. A computer program product comprising instructions, which, when executed on at least one processor, cause the at least one processor to carry out the methodaccording to any of the claims 1 -11 , as performed by the UE (10) and the radio network node (120), respectively.

24. A computer-readable storage medium, having stored thereon a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any of the claims 1 -11 , as performed by the UE (10) and the radio network node (120), respectively.

Images