Wireless device for receiving OD-SSB and method thereof

Abstract

A method, network node and user equipment (UE) for renewal of an on-demand synchronization signal block (OD-SSB) timer are disclosed According to one aspect, a method in a UE includes receiving from the network node an indication of an on-demand synchronization signal block (OD-SSB) activation condition. The method also includes restarting an OD-SSB deactivation timer when the activation condition occurs.

Description

[0001] WIRELESS DEVICE FOR RECEIVING OD-SSB AND METHOD THEREOF

[0002] The present application claims the priority to and the benefit of U.S. Provisional Patent Application No. 63 / 755412, filed 2025-02-07, the disclosure of which is hereby incorporated herein by reference of its entirety.

[0003] TECHNICAL FIELD

[0004] The present disclosure relates to wireless communications, and in particular, to provision of on-demand synchronization signal block of a secondary cell.

[0005] BACKGROUND

[0006] The Third Generation Partnership Project (3GPP) is developing New Radio (NR) wireless communication system which supports carrier aggregation of up to 16 component carriers. A user equipment (UE) capable of carrier aggregation may transmit / receive on multiple component carriers at the same time, where different component carriers may be of different channel bandwidths and / or duplex schemes.

[0007] In NR specifications, a component carrier is referred to as a cell. One of the cells is known as the primary cell (PCell) and is the cell that the UE initially connects to. After the UE is connected, one or multiple secondary cells (SCells) may be additionally configured. Furthermore, the SCells may be dynamically activated / deactivated depending on traffic load. The dynamic signaling may be via a medium access control (MAC) control element (CE). When carrier aggregation is not configured, UE may transmit and receive only on the PCell.

[0008] To manage power consumption and network efficiency, SCells can be dynamically activated and deactivated based on traffic demands. In NR, unless direct SCell activation is configured, SCell activation is typically indicated by the network node to the UE for a radio resource control (RRC) configured SCell via MAC CE signaling, specifically via a kind of SCell activation / deactivation MAC CE.

[0009] NR supports both explicit SCell deactivation, in which the network node sends to the UE an SCell activation / deactivation MAC CE indicating to the UE that SCell is to be deactivated, and implicit SCell deactivation, in which SCell is deactivated upon the expiry of an SCell deactivation timer (i.e., without explicit signaling). Implicit SCell deactivation may be referred to as timer-based SCell deactivation.

[0010] Synchronization Signal Blocks (SSBs) serve as fundamental reference signals in wireless networks, providing synchronization, measurement references, and otherfunctions for connected devices. Traditionally, SSBs are transmitted continuously at regular intervals to maintain network coverage and connectivity. However, to further improve energy efficiency, on-demand SSB (OD-SSB) transmission has been introduced, where SSBs are provided temporarily based on specific procedures or UE requests rather than being continuously transmitted. The SSBs continuously being transmitted may be referred to as always-on SSB (AO-SSB) in a cell.

[0011] The coordination between different timer-based mechanisms in wireless systems presents various operational considerations. For instance, when SCells utilize OD-SSB transmission, the duration of SSB provision may need to align with other network procedures and timer operations to maintain proper system functionality. The management of multiple concurrent timers and their interactions can affect the overall performance and reliability of wireless communication systems.

[0012] As wireless networks continue to evolve toward greater energy efficiency while maintaining service quality, there is an ongoing development of mechanisms to coordinate various timer-based procedures and resource provisioning schemes. These developments aim to balance power savings with the maintenance of adequate signal coverage and system performance across different network scenarios and use cases.

[0013] 3GPP RAN2 is currently discussing the mechanism for OD-SSB activation or deactivation. An open question is whether the MAC CE for OD-SSB activation or deactivation may also indicate SCell activation or deactivation at the same time.

[0014] SUMMARY

[0015] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0016] Some embodiments advantageously provide methods, network nodes, and UEs for renewal of an on-demand synchronization signal block (OD-SSB) timer.

[0017] According to one aspect of the present disclosure, a method performed by a wireless device is provided, where while the wireless is receiving OD-SSB from a secondary cell (SCell) of the wireless device, it receives an indication of ta trigger event associated with the provision of the OD-SSBs of the SCell.

[0018] In some embodiments, in response to the trigger event, the wireless device renews or restarts a deactivation timer of the SCell, depending on whether the current status of theSCell is active or non-active. And the OD-SSB provision timer is renewed at least until the deactivation time expires.

[0019] In some embodiments, the trigger event is an OD-SSB activation command by MAC CE. In some further embodiments, the wireless device is configured with a number of OD-SSB configurations, each of which is associated with a candidate value. The OD-SSB activation command contains a candidate value so that the associated OD-SSB configuration is to be utilized by the wireless device.

[0020] According to another aspect of the present disclosure, a method performed by a network node is provided. The network node sends to a wireless device an indication of a trigger event associated with provision of OD-SSBs from an SCell of the wireless device. The network node could be the SCell providing the OD-SSB, a PCell or another SCell of the wireless device.

[0021] In some embodiments, a number of OD-SSB configurations are transmitted by the network node to the wireless device. In some embodiment, the trigger event is a OD-SSB activation command by MAC CE, which includes a value associated with one of the number of OD-SSB configurations. Some embodiments, provide support for timer-based SCell deactivation or the connected mode Discontinuous Reception (C-DRX) active period together with timer-based OD-SSB deactivation and / or finite-duration OD-SSB provision.

[0022] According to another aspect of the present disclosure, a wireless device and a network node configured to perform the embodiments described hereinafter are provided.

[0023] BRIEF DESCRIPTION OF THE DRAWINGS

[0024] A more complete understanding of the present embodiments, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

[0025] FIG. 1 is an SCell activation / deactivation MAC / CE;

[0026] FIG. 2 is an enhanced SCell activation / deactivation MAC / CE;

[0027] FIG. 3 is a schematic diagram of an example network architecture illustrating a communication system according to principles disclosed herein;

[0028] FIG. 4 is a block diagram of a network node in communication with a user equipment over a wireless connection according to some embodiments of the present disclosure;FIG. 5 is a flowchart of an example process in a user equipment for renewal of an OD-SSB timer according to some embodiments of the present disclosure;

[0029] FIG. 6 is a flowchart of an example process in a network node for renewal of an on-demand synchronization signal block (OD-SSB) timer according to some embodiments of the present disclosure;

[0030] FIG. 7 is a flowchart of an example process in a user equipment for renewal of an on-demand (OD-SSB timer according to some embodiments of the present disclosure.

[0031] FIG. 8 is a flowchart of an example process in a network node for OD-SSB provision and SCell activation according to some embodiments of the present disclosure.

[0032] DETAILED DESCRIPTION

[0033] Before describing in detail example embodiments, it is noted that the embodiments reside primarily in combinations of apparatus components and processing steps related to renewal of an on-demand synchronization signal block (OD-SSB) timer. Accordingly, components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

[0034] As used herein, relational terms, such as “first” and “second,” and the like, may be used solely to distinguish one entity or element from another entity or element without necessarily requiring or implying any physical or logical relationship or order between such entities or elements. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the concepts described herein. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and / or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0035] In embodiments described herein, the joining term, “in communication with” and the like, may be used to indicate wireless communication, which may be accomplished by radio signaling, for example. One having ordinary skill in the art will appreciate that multiple components may interoperate and modifications and variations are possible of achieving the communication.In some embodiments described herein, the term “coupled,” “connected,” and the like, may be used herein to indicate a connection, although not necessarily directly, and may include wired and / or wireless connections.

[0036] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the concepts described herein. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and / or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0037] The term “network node” used herein may be any kind of network node comprised in a radio network which may further comprise any of base station (BS), radio base station, base transceiver station (BTS), base station controller (BSC), radio network controller (RNC), g Node B (gNB), evolved Node B (eNB or eNodeB), Node B, multistandard radio (MSR) radio node such as MSR BS, multi-cell / multicast coordination entity (MCE), relay node, donor node controlling relay, radio access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU) Remote Radio Head (RRH), a core network node (e.g., mobile management entity (MME), self-organizing network (SON) node, a coordinating node, positioning node, MDT node, etc.), an external node (e.g., 3rd party node, a node external to the current network), nodes in distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The network node may also comprise test equipment. In some embodiments, the non-limiting terms wireless device (WD) or a user equipment (UE) are used interchangeably. The UE herein may be any type of user equipment capable of communicating with a network node or another UE over radio signals, such as a wireless device (WD). The UE may also be a radio communication device, target device, device to device (D2D) UE, machine type UE or UE capable of machine to machine communication (M2M), low-cost and / or low-complexity UE, a sensor equipped with UE, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), an Internet of Things (loT) device, or a Narrowband loT (NB-IOT) device etc.

[0038] Note that although terminology from one particular wireless system, such as, for example, 3GPP LTE and / or New Radio (NR) and / or 6G, may be used in this disclosure,this should not be seen as limiting the scope of the disclosure to only the aforementioned system. It is contemplated that other 3GPP systems may make use of the concepts and arrangements disclosed herein. For example, a disclosure relating to NR may also be implementable in a 6G system and / or an LTE system, a disclosure relating to 6G may also be implementable in a NR and / or LTE system, and a disclosure relating to LTE may also be implementable in a NR and / or 6G system. Other wireless systems, including without limitation Wide Band Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMax), Ultra Mobile Broadband (UMB) and Global System for Mobile Communications (GSM), may also benefit from exploiting the ideas covered within this disclosure.

[0039] Note further, that functions described herein as being performed by a network node may be distributed over a plurality of network nodes. In other words, it is contemplated that the functions of the network node and user equipment described herein are not limited to performance by a single physical device and, in fact, may be distributed among several physical devices.

[0040] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0041] Returning to timer-based SCell deactivation in a NR system, upon expiry of the SCell deactivation timer in slot n, the UE shall perform actions related to SCell deactivation no later than slot n + m, where m is an offset that depends on the numerology. The length of timer is optionally configured by the network node and indicated to the UE via RRC signaling, specifically by the sCellDeactivationTimer field in ServingCellConflg IE, whose value, if configured, is one of {ms20, ms40, ms80, ms!60, ms200, ms240, ms320, ms400, ms480, ms520, ms640, ms720, ms840, ms 1280}. If timerbased SCell deactivation is not configured, such as the optional field sCellDeactivationTimer is not provided, the UE may assume that the SCell deactivation timer is set to infinity. In this case, the SCell may be deactivated only via explicit signaling.

[0042] Since it may not be known upon sending the SCell activation command how long the SCell is to remain activated, NR supports mechanisms for renewing / restarting theSCell deactivation timer. In particular, according to 3GPP Technical Standard (TS) 38.321, the SCell deactivation timer is renewed or restarted if 1) a MAC packet date unit (PDU) is scheduled on the SCell or if 2) the network node sends a new

[0043] activation / deactivation MAC CE indicating that the SCell is activated.

[0044] Note that the UE receives an MAC CE indicating SCell activation in slot n, the UE may start or restart the timer-based in slot n + k, where k is an offset that depends on the numerology and on the slot in which the UE sends a subsequent hybrid automatic repeat request acknowledgement such as HARQ-ACK.

[0045] Examples of existing SCell activation / deactivation MAC CEs are shown in FIG. 1, in which the MAC CE of one octet is identified by a MAC sub header with Logical Channel Identity (LCID) as specified in Table 6.2.1-1 of 3GPP TS 38.321. It has a fixed size and consists of a single octet containing seven C-fields and one R-field. The Ci: is defined as follow If there is an SCell configured for the MAC entity with SCelllndex i as specified in 3GPP TS 38.331, this field indicates the activation / deactivation status of the SCell with SCelllndex i, else the MAC entity shall ignore the Ci field. The Ci field is set to 1 to indicate that the SCell with SCelllndex i shall be activated. The Ci field is set to 0 to indicate that the SCell with SCelllndex i is to be deactivated.

[0046] There is another existing SCell activation / deactivation MAC CE of four octets that may support up-to 31 SCells. In this MAC CE signaling, network has to indicate the wanted activation status for each configured SCell. And yet an enhanced SCell activation / deactivation MAC CE, wherein along with the SCell activation message, the network node may indicate to the UE whether a tracking reference signal (TRS) for SCell activation is also triggered, as shown in FIG. 2.

[0047] Similar to the SCell deactivation timer described above, there are other configurations that are provided to a UE during a limited time period. Similar to the SCell scenario, upon activation, a timer is started in the UE / network node and upon timeout and data inactivity, the configuration is reverted to a default configuration. On the other hand, upon data activity, the timers are restarted.

[0048] Another example is the bandwidth part (BWP) inactivity timer which is a parameter that controls the switching between different BWPs based on user activity and if no data is being transmitted or received, the inactivity timer starts. Once the timer expires, the UE moves to a default BWP.

[0049] Yet another example is related to the UE discontinuous reception, such as C-DRX, and the interarrival time (IAT) defining the duration the UE should wait in an active stateafter data transmission or reception before entering a low-power DRX sleep / off cycle. If no data is transmitted and / or received for a certain period defined by I AT, the UE moves to the DRX off period. If new data arrives, the UE immediately wakes up and resets the inactivity timer.

[0050] Returning to OD-SSB provision, in the current NR deployments, SSBs are typically configured statically, with e.g., 20 ms period, with constant power and spatial configuration for initial access cells and serve as de-facto coverage indicators. If a UE detects an SSB indicating a cell at a certain location, with a certain signal strength that allows finding and connecting to the network node, it may usually make a robust assumption that the same cell will be available in a predictable manner in the future, with a sufficient signal strength, or at least the network node has activated another cell providing coverage at the same location.

[0051] In ongoing NR evolution, SSBs are provided temporarily to UEs whose functionality or performance may be improved if additional signals for e.g., loop convergence, synchronization, measurements, or other signal processing steps are available. In some scenarios, a cell may be transmitting baseline SSBs at a lower rate, e.g., 160 ms or 20 ms, also referred to as always-on SSB, or no SSBs may be transmitted as a baseline. The network node may then activate additional SSBs or SSB bursts, e.g., with period 20 ms or 5 ms, respectively, in association with certain procedures, or based on a UE requesting them, otherwise known as OD-SSB. OD-SSBs may also be one-shot transmissions or limitedduration SSB bursts, without a recurrent structure. They may be transmitted at the same or at a different power level and spatial configuration than the baseline SSB.

[0052] In a previous 3GPP meeting RANI# 118, it was agreed that OD-SSB transmission is indicated to the UE via MAC CE signaling “for Scenarios #2 and #2A In the following meeting RAN1#119, it was agreed that both explicit (see Option 1 below) and implicit OD-SSB deactivation (see Option 2 below) will be supported:

[0053] “For a cell supporting on-demand SSB SCell operation, support at least the following options to deactivate on-demand SSB transmission from a UE perspective.

[0054] • Option 1: Explicit indication of deactivation for on-demand SSB via MAC-CE for on-demand SSB transmission indication

[0055] Deactivation by RRC is up to RAN2

[0056] FFS: Which scenario Option 1 is used

[0057] • Option 2: Configuration / indication of the number N of on-demand SSB bursts to be transmitted after on-demand SSB is indicated

[0058] FFS: Whether Option 4, 4a is needed in addition to Option 2

[0059] FFS: Whether the value of N can be implicitly determined using a timer. " In explicit OD-SSB deactivation, see Option 1 above, the NW sends to the UE a MAC CE indicating that OD-SSB is turned off. In implicit OD-SSB deactivation, seeOption 2 above, the UE assumes that the NW turns off SSB after some duration after it received an indication that OD- SSB was turned on. The length of the duration is determined by an OD-SSB provision timer, which is also referred to as OD-SSB deactivation timer, since when the timer expires, the transmission or provision of the OD-SSB is considered as deactivated. For Option 2, also referred to as timer-based OD-SSB deactivation, it is an open question whether the finite OD-SSB duration will be explicitly determined by a number N of OD-SSB bursts or whether the finite OD-SSB duration will be implicitly determined using a timer, which hereinafter also referred to as OD-SSB transmission timer or OD-SSB provision timer.

[0060] The network node is expected to provide an SSB to the UE while a UE’s SCell is in an activated state. If OD-SSB is the only SSB provided in the SCell, it may need to be provided, at least, while an SCell is in an active state. Then, with explicit (using MAC CE) OD-SSB deactivation, timer-based SCell deactivation may be supported, as long as the MAC CE carrying the OD-SSB deactivation command is received by the UE after the SCell deactivation timer has expired.

[0061] An open question, however, is whether implicit (timer-based) OD-SSB deactivation may be supported in combination with other timer-based procedures such as SCell deactivation. Since SCell deactivation timer may be renewed at any time, no OD-SSB provision of finite duration may guarantee that OD-SSB is provided for the entirety of SCell active period.

[0062] Similar problems may arise in future if OD-SSB provision is associated with other type of timer-based procedures, such as BWP inactivity timer, C-DRX IAT, and alike.

[0063] Some embodiments are directed to renewal of an OD-SSB timer.tRetuming to a communication system 10 as shown in FIG. 3 as a schematic diagram, a 3GPP-type cellular network may support standards such as LTE and / or NR (5G) and / or 6G, which comprises an access network 12, such as a radio access network, and a core network 14. The core network 14 includes one or more network nodes 15. The access network 12 comprises a plurality of network nodes 16a, 16b, 16c (referred to collectively as network nodes 16, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 18a, 18b, 18c (referred to collectively as coverage areas 18. Each network node 16a, 16b, 16c is connectable to the core network 14 over a wired or wireless connection 20. A first user equipment (UE) 22a located in coverage area 18a is configured to wirelessly connect to, or be paged by, the corresponding network node 16a. A second UE 22b in coverage area 18b is wirelessly connectable to the correspondingnetwork node 16b. While a plurality of UEs 22a, 22b (collectively referred to as user equipments 22 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding network node 16. Note that although only two UEs 22 and three network nodes 16 are shown for convenience, the communication system may include many more UEs 22 and network nodes 16.

[0064] As one example, in certain embodiments, access network 12 may contain some access network nodes 16 that support 3GPP radio access technologies (RAT), such as LTE or NR, while other access network nodes 16 support (or the same access network nodes 16 additionally support) non-3GPP RATs, such as Wi-Fi or a proprietary RAT. As another example, communication system 10 may support multiple generations of related communication standards (e.g., 4G, 5G and 6G 3GPP communication standards) and, as a result, may include an access network 12 and / or a core network 14 that supports multiple different standard generations or may include multiple access networks 12 and / or multiple core networks 14 with individual networks supporting different standards generations.

[0065] Also, it is contemplated that a UE 22 may be in simultaneous communication and / or configured to separately communicate with more than one network node 16 and more than one type of network node 16. For example, a UE 22 may have dual connectivity with a network node 16 that supports LTE and the same or a different network node 16 that supports NR. As an example, UE 22 may be in communication with an eNB for LTE / E-UTRAN, a gNB for NR / NG-RAN (i.e., being configured for multiradio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC) and / or Wi-Fi.

[0066] A network node 16 (eNB or gNB) is configured to include a configuration unit 24 which may be configured to perform one or more network node 16 functions as described herien such as, for example, configuring the UE with an indication of OD-SSB activation condition, or further, configurating the UE with a number of OD-SSB configurations. A user equipment 22 is configured to include a timer unit 26 which may be configured to perform one or more UE 22 functions as described herein such as, for example, restarting an OD-SSB provision timer, also referred to as OD-SSB deactivation timer, when the activation condition occurs.

[0067] Example implementations, in accordance with an embodiment, of the UE 22 and network node 16 discussed in the preceding paragraphs will now be described with reference to FIG. 4.The communication system 10 includes a network node 16 provided in a communication system 10 and including hardware 28 enabling it to communicate with the UE 22. The hardware 28 may include a communication interface 29 comprising a radio interface 30 for setting up and maintaining at least a wireless connection 32 with a UE 22 located in a coverage area 18 served by the network node 16. The radio interface 30 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers. The radio interface 30 includes an array of antennas 34 to radiate and receive signal(s) carrying electromagnetic waves.

[0068] In the embodiment shown, the hardware 28 of the network node 16 further includes processing circuitry 36. The processing circuitry 36 may include a processor 38 and a memory 40. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 36 may comprise integrated circuitry for processing and / or control, e.g., one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Array) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 38 may be configured to access (e.g., write to and / or read from) the memory 40, which may comprise any kind of volatile and / or nonvolatile memory, e.g., cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0069] Thus, the network node 16 further has software 42 stored internally in, for example, memory 40, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the network node 16 via an external connection. The software 42 may be executable by the processing circuitry 36. The processing circuitry 36 may be configured to control any of the methods and / or processes described herein and / or to cause such methods, and / or processes to be performed, e.g., by network node 16.

[0070] Processor 38 corresponds to one or more processors 38 for performing network node 16 functions described herein. The memory 40 is configured to store data, programmatic software code and / or other information described herein. In some embodiments, the software 42 may include instructions that, when executed by the processor 38 and / or processing circuitry 36, causes the processor 38 and / or processing circuitry 36 to perform the processes described herein with respect to network node 16. For example, processing circuitry 36 of the network node 16 may include a configuration unit 24 which may be configured to perform one or more network node 16 functions as described herein such as,for example, configuring the UE with an indication of an on-demand synchronization signal block (OD-SSB) activation condition.

[0071] The network node 16 may be composed of multiple distinct network entities, which may each have or utilize their own respective physical components. In certain scenarios in which the network node 16 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 16 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memories 40 or portions of memory 40 for different RATs) and some components may be reused (e.g., a same antenna may be shared by different RATs). The network node 16 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 16, for example NR, future generation (6G), 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 16.

[0072] In certain alternative embodiments, network node 16 may be capable of wireless communication but does not include separate radio front-end circuitry, instead, the processing circuitry 36 includes radio front-end circuitry and is connected to the antenna 34. Similarly, in some embodiments, all or some of the RF receivers, transmitters and / or transceivers are part of the radio interface 30. In still other embodiments, the communication interface 29 includes one or more ports or terminals, the radio interface 30, and the RF receiver, transmitter and / or transceiver, and the communication interface 31 communicates with baseband processing circuitry, which is part of a digital unit (not shown).

[0073] The antenna 34 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 34 may be coupled to the radio front-end circuitry in radio interface 30 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 34 is separate from the network node 16 and connectable to the network node 16 through one or more interfaces or ports.Network node 16 may include one or more components described above with respect to network node 16, e.g., communication interface 29, radio interface 30, antenna 34, ports, processing circuitry 36, processor 38, memory 40 and software 42. These elements of network node 15 may be arranged such that network node 15 may perform various core network functions. Network node 15 may communicate wirelessly or via a wired connection with network nodes 16 via communication link 59.

[0074] The communication system 10 further includes the UE 22 already referred to. The UE 22 may have hardware 44 that may include a radio interface 46 configured to set up and maintain a wireless connection 32 with one or more network nodes 16 each serving a coverage area 18 in which the UE 22 is currently located. The radio interface 46 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers. The radio interface 46 includes an array of antennas 48 to radiate and receive signal(s) carrying electromagnetic waves.

[0075] Communication functions of the radio interface 46 may include cellular communication, Wi-Fi communication, 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, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / intemet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0076] The hardware 44 of the UE 22 further includes processing circuitry 50. The processing circuitry 50 may include a processor 52 and memory 54. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 50 may comprise integrated circuitry for processing and / or control, e.g., one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Array) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 52 may be configured to access (e.g., write to and / or read from) memory 54, which may comprise any kind of volatile and / or nonvolatile memory, e.g., cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).Thus, the UE 22 may further comprise software 56, which is stored in, for example, memory 54 at the UE 22, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the UE 22. The software 56 may be executable by the processing circuitry 50. The software 56 may include a client application 58. The client application 58 may be operable to provide a service to a human or non-human user via the UE 22.

[0077] The processing circuitry 50 may be configured to control any of the methods and / or processes described herein and / or to cause such methods, and / or processes to be performed, e.g., by UE 22. The processor 52 corresponds to one or more processors 52 for performing UE 22 functions described herein. The UE 22 includes memory 54 that is configured to store data, programmatic software code and / or other information described herein. In some embodiments, the software 56 and / or the client application 58 may include instructions that, when executed by the processor 52 and / or processing circuitry 50, causes the processor 52 and / or processing circuitry 50 to perform the processes described herein with respect to UE 22. For example, the processing circuitry 50 of the user equipment 22 may include a timer unit 26 which may be configured to perform one or more UE 22 functions as described herein such as, for example, restarting an OD-SSB deactivation timer when the activation condition occurs.

[0078] In some embodiments, the inner workings of the network node 16 and UE 22 may be as shown in FIG. 4 and independently, the surrounding network topology may be that of FIG. 3.

[0079] The wireless connection 32 between the UE 22 and the network node 16 is in accordance with the teachings of the embodiments described throughout this disclosure. More precisely, the teachings of some of these embodiments may improve the data rate, latency, and / or power consumption and thereby provide benefits such as reduced user waiting time, relaxed restriction on file size, better responsiveness, extended battery lifetime, etc. In some embodiments, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve.

[0080] FIG. 5 is a flowchart of an example process in a user equipment 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of user equipment 22 such as by one or more of processing circuitry 50 (including the timer unit 26), processor 52, and / or radio interface 46.A method performed by a wireless device is provided, where while the wireless is receiving OD-SSB from a secondary cell (SCell) of the wireless device, it receives (S40) an indication of a trigger event associated with the provision of the OD-SSBs of the SCell. Then, the wireless device renews (S42) the OD-SSB provision timer (since the wireless is receiving OD-SSB from the SCell, the OD-SSB provision timer should be running at the time of receiving the indication).

[0081] In some further embodiments, in response to the trigger event, the wireless device renews or restarts a deactivation timer of the SCell, depending on whether the current status of the SCell is active or non-active. And the OD-SSB provision timer is renewed at least until the deactivation time expires.

[0082] In some further embodiments, the trigger event is an OD-SSB activation command by MAC CE. In some further embodiments, the wireless device is configured with a number of OD-SSB configurations, each of which is associated with a candidate value. The OD-SSB activation command contains a candidate value so that the associated OD-SSB configuration is to be utilized by the wireless device.

[0083] FIG. 6 is a flowchart of an example process in a network node 16 for renewal of an on-demand synchronization signal block (OD-SSB) timer. One or more blocks described herein may be performed by one or more elements of network node 16 such as by one or more of processing circuitry 36 (including the configuration unit 24), processor 38, and / or radio interface 30. Network node 16 is configured to configure the UE 22 with an indication of an on-demand synchronization signal block (OD-SSB) activation condition (Block S10). The network node 16 is further configured to configure the UE 22 to restart an OD-SSB deactivation timer when the activation condition occurs (Block S12).

[0084] In some embodiments, wherein the OD-SSB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer. In some embodiments, the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n. In some embodiments, the process includes configuring the UE 22 to maintain a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing. In some embodiments, a duration of an OD-SSB configured to be not less than a duration of a secondary cell (SCell) deactivation timer.

[0085] FIG. 7 is a flowchart of an example process in a user equipment 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of user equipment 22 such as by one or more ofprocessing circuitry 50 (including the timer unit 26), processor 52, and / or radio interface 46. User equipment 22 is configured to receive from the network node 16 an indication of an on-demand synchronization signal block (OD-SSB) activation condition (Block S14). UE 22 is further configured to restart an OD-SSB deactivation timer when the activation condition occurs (Block SI 6).

[0086] In some embodiments, the OD-SSB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer. In some embodiments, the OD-SSB deactivation timer is restarted when a medium access control (MAC) control element (CE) is received on a secondary cell (SCell). In some embodiments, the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n. In some embodiments, the method includes restarting an SCell deactivation timer assuming that an OD-SSB is transmitted for at least a minimum number of SSB bursts after slot n+k. In some embodiments, the process includes receiving an indication to prolong a duration of the OD-SSB deactivation timer. In some embodiments, the process includes maintaining a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing. In some embodiments, a duration of the OD-SSB is not less than a duration of a secondary cell (SCell) deactivation timer. In some embodiments, an OD-SSB and a secondary cell (SCell) are determined to be active when either the OD-SSB deactivation timer and an secondary cell (SCell) deactivation timer are running. In some embodiments, a starting point for OD-SSB retransmission is configured by the network node 16.

[0087] Having described the general process flow of arrangements of the disclosure and having provided examples of hardware and software arrangements for implementing the processes and functions of the disclosure, the sections below provide details and examples of arrangements for renewal of an on-demand synchronization signal block (OD-SSB) timer.

[0088] One or more network node 16 functions described below may be performed by one or more of processing circuitry 36, processor 38, configuration unit 24, communication interface 29, etc. One or more UE 22 functions described below may be performed by one or more of processing circuitry 50, processor 52, timer unit 26, radio interface 46, etc.

[0089] For the sake of simplicity, a scenario which is currently being considered in 3GPP, namely the OD-SSB provision in association to carrier aggregation and more specifically an SCell’s deactivation timer, are discussed. However, principles disclosed herein are also equally applicable to other scenarios where an inactivity timer is relevant for a UE 22operation, such as C-DRX. In some embodiments, these timers or events that would have led to restart of those timers also leads to restart of the OD-SSB provision timer. In some embodiments, the UE 22 may be preconfigured one or more of those timers such as C-DRX IAT, and / or BWP inactivity, and / or SCell deactivation timer restart that lead to restart of the OD-SSB provision timer.

[0090] The disclosure below is discussed in the context of carrier aggregation where it is assumed that at least timer-based OD-SSB deactivation is configured for an SCell. In some embodiments, it may be assumed that timer-based SCell deactivation is configured as well, although it is not strictly required.

[0091] 3GPP ongoing discussion has considered that the OD-SSB duration may be measured in a number N of OD-SSB bursts or by a timer. Here, for simplicity, implicit OD-SSB deactivation is referred to as timer-based OD-SSB deactivation.

[0092] In some embodiments, an event that restarts the SCell deactivation timer (if configured) also restarts or renews the OD-SSB deactivation timer.

[0093] In some embodiments, an OD-SSB deactivation timer for an SCell is restarted if a MAC PDU is received on the SCell.

[0094] In some embodiments, an OD-SSB deactivation timer for an SCell is restarted once the UE 22 receives a MAC CE (e.g., on the PCell or on another SCell) indicating that OD-SSB is activated and / or that the SCell is activated.

[0095] The action that renews the OD-SSB deactivation timer may be same or different from the action that renews the SCell deactivation timer.

[0096] In some embodiments, if the UE 22 receives a MAC CE indicating both OD-SSB and SCell (re)activation in slot n, the UE 22 restarts the SCell deactivation timer and assumes that OD-SSB is transmitted for at least N SSB bursts after slot n + k. The value of N may be provided to the UE 22 via RRC signaling or indicated in the MAC CE, for example, from a list of RRC configured candidate values. Further, each of the candidate values is included in an OD-SSB configuration configured for the UE, so that the value N can indicate which OD-SSB configuration is to apply. Alternatively, an OD-SSB configuration configured for the UE may include the list of candidate values.

[0097] In some embodiments, if the UE 22 receives for an SCell a MAC CE indicating both its OD-SSB and (re)activation, the UE 22 restarts both the SCell deactivation timer and the OD-SSB transmission timer, or a single timer for both, namely e.g., an onDemandSSBAndSCellDeactivationTimer. The duration of the timer(s) may be provided to the UE 22 via RRC signaling or indicated in the MAC CE, for example, from a list ofRRC configured candidate timer durations. Further, the candidate timer durations correspond respectively to a plurality of OD-SSB configurations configured for the UE. Alternatively, an OD-SSB configuration configured for the UE may include the list of candidate timer durations.

[0098] In some embodiments, if the UE 22 receives for an SCell a MAC CE indicating SCell (re)activation, the UE 22 restarts both the SCell deactivation timer and the OD-SSB transmission / provision timer, or a single timer called, e.g., an onDemandSSBAndSCellDeactivationTimer. The duration of the timer(s) may be provided to the UE 22 via RRC signaling or indicated in the MAC CE, for example, from a list of RRC configured candidate timer durations.

[0099] In some embodiments, the UE 22 may be preconfigured (e.g., via RRC signaling) with whether an OD-SSB provision timer is to be prolonged or not in conjunction with the SCell reactivation. If the UE 22 is configured to prolong the OD-SSB provision timer in response to the SCell reactivation, when the UE 22 receives, for an activated SCell, a MAC CE indicating SCell (re)activation, the UE 22 restarts both the SCell deactivation timer and the OD-SSB transmission timer, or a single timer functions both, e.g., an onDemandSSBAndSCellDeactivationTimer. The duration of the timer(s) may be provided to the UE 22 via RRC signaling or indicated in the MAC CE (e.g., from a list of RRC configured candidate timer durations).

[0100] In some of the above embodiments, the SCell deactivation timer and the OD-SSB provision timer can belong to a same timer, i.e., the UE 22 maintains only one timer for both purposes. In some embodiments, a new parameter, called, e.g., onDemandSSBAndSCellDeactivationTimer configures the timer. In an alternate embodiment, legacy sCellDeactivationTimer is repurposed / extended to also consider as OD-SSB provision / transmission timer.

[0101] In some embodiments, the SCell deactivation timer and the OD-SSB provision timer are separate . In this case, the UE 22 expects the indicated value of onDemandDeactivationTimer to be larger than or equal to the value of sCellDeactivationTimer such that OD-SSB is provided for at least the duration when the SCell is assumed to be active. This restriction may be given in RRC field descriptions of the timers.

[0102] In some embodiments, when the SCell deactivation timer and the OD-SSB provision timer are separate, the UE 22 considers both the SCell and OD-SSB transmission to be active as long as one of these timers are running. Alternatively, the UE22 considers OD-SSB transmission to be active at least as long as the SCell deactivation timer is running. Alternatively, the OD-SSB provision timer is restarted if it is expiring while the SCell deactivation timer is running.

[0103] In some embodiments, the start point of the OD-SSB retransmission is at slot n + p after the SCell deactivation timer renewed or restarted (depending on the current status of the SCell is active or inactive) at slot n. The offset p is indicated by the network node 16.

[0104] In some embodiments, the start point of the OD-SSB retransmission should follow the same OD-SSB transmission pattern as before the SCell deactivation timer was renewed or restarted. The duration between the first OD-SSB retransmission occasion and the last OD-SSB transmission occasion before the SCell deactivation timer was renewed / restarted is M multiplied with the OD-SSB transmission periodicity. The value M may be predefined or configured / indicated by the network node 16. For example, M equals 1.

[0105] In some embodiments, the value N of OD-SSB bursts may be inferred by the UE 22 by the value of OD-SSB and / or SCell deactivation timer and the value of the (active) OD-SSB periodicity. For example, if the length of SCell deactivation timer is 1280 ms and the OD-SSB periodicity is 20 ms, the number of OD-SSB bursts is TV = 1280 / 20 = 64.

[0106] In some embodiments, the UE 22 is not configured with a timer for SCell deactivation for SCells that do not have always-on SSB. In this case the UE 22 assumes the timer value is infinite. If the UE 22 is configured with a timer for OD-SSB provision, the timer for OD-SSB provision is always restarted or renewed if the SCell is still active, for example, the UE 22 has not received explicit deactivation signaling for the SCell.

[0107] In some embodiments, the UE 22 is not configured for timer for OD-SSB deactivation of SCells that do not have always-on SSB. In this case the UE 22 assumes OD-SSB is active unless explicitly deactivated.

[0108] In some embodiments, the UE 22 is not configured for timer for SCell deactivation or for timer for OD-SSB provission of SCells that do not have always-on SSB. This may be reflected in the field descriptions of the timers.

[0109] In some embodiments, the restart or renewing of OD-SSB provision timer is triggered by the reception of a PDSCH or by the scheduling of a PDSCH. I.e. similar triggering mechanism as for C-DRX but not explicitly linked to the C-DRX inactivity timer. An example use case for this is for certain types of UEs 22 that are not battery powered (e.g., fixed wireless access) or UEs 22 currently active with very latency sensitive services that do not have any C-DRX IAT configured, or that have an IAT that is extremely long (e.g., 100 seconds).Figure 8 is a flowchart of an example process in a network node 16 according to some embodiments of the present disclosure.

[0110] At step S44, the network node, as an SCell of a wireless device, provides the wireless device with OD-SSBs while the OD-SSB provision timer is running. While step S44 is ongoing, at step S46, the network node sends an indication of a trigger event associated with provision of OD-SSBs from the SCell.

[0111] Note that the network node sending the indication to the wireless device might be another node instead of the node providing the SCell to the wireless device. And in this circumstance, S44 is not performed by the SCell providing the OD-SSB, but a PCell or another SCell of the wireless device.

[0112] Some examples may include one or more of the following:

[0113] Example 1. A method in a UE 22 for renewing / restarting or extending an OD-SSB deactivation timer based on, e.g., one or more of:

[0114] Receiving from a network node 16 an OD-SSB (re)activation indication.

[0115] Receiving from a network node 16 a configuration parameter indicative of whether an OD-SSB shall be reactivated in association with certain event.

[0116] Example 2. Example where the OD-SSB (re)activation indication / event is triggered by the same actions that would have renewed / restarted one or more of:

[0117] The SCell deactivation timer;

[0118] The SCell’s associated C-DRX IAT; and / or

[0119] The BWP IAT.

[0120] Example 3. Any one of Examples 1-2 where the OD-SSB (re)activation indication also / additionally renews / restarts the SCell deactivation timer, C-DRX IAT, and / or BWP IAT.

[0121] Example 4. Any one of Examples 1-3 where the event for OD-SSB provision timer restart / reactivation is the restart of the SCell deactivation timer and / or C-DRX IAT and / or BWP IAT.

[0122] Example 5. Any one of Examples 1-4 were the UE 22 is configured with which of events (restart of the SCell deactivation timer and / or C-DRX IAT and / or BWP IAT) should lead to restart of the OD-SSB provision timer.

[0123] Example 6. Any one of Examples 1-5 where the configuration parameter is provides per OD-SSB, e.g., as a list of events (event_l, event_2, etc.) that if they occur shall trigger a restart of the deactivation timer associated with the OD-SSB.Example 7. Any one of Examples 1-6 where the configuration parameter is provides per event e.g., as a list of OD-SSBs (OD-SSB l, OD-SSB 2, etc.) that shall restart their deactivation timers if the event occurs.

[0124] Example 8. Any one of Examples 1-8 where where the lists are encoded as bitmaps where each bit indicating an event or an OD-SSB .

[0125] Example 9. Any one of Examples 1-8 where the timer / valid duration of OD-SSB (re)activation is the same as the timer value of the event, such as the SCell deactivation restart timer and / or C-DRX IAT and / or BWP inactivity timer.

[0126] Example 10. Any one of Examples 1-9 where the event timer renewed / restarted at the slot n, the first OD-SSB (re)transmission occasion is expected after slot n + k.

[0127] Example 11. Any one of Examples 1-10 where the last OD-SSB transmission at slot m which is before the event timer renewed / restarted at the slot n, the first OD-SSB (re)transmission occasion is expected as smallest value of (m + N*OD-SSB periodicity) which is larger than slot n.

[0128] Example 12. Any one of Examples 1-11 where the OD-SSB (re)activation indication is a MAC CE.

[0129] Example 13. Any one of Examples 1-12 wherein an OD-SSB (re)activation indication (or event) in slot n explicitly indicates a number, N, of SSB bursts that the UE 22 expects the network node 16 to transmit after slot n + k.

[0130] Example 14. Any one of Examples 1-13 wherein an OD-SSB (re)activation indication (or event) in slot n explicitly indicates a time window, W. including SSB bursts that the UE 22 expects the network node 16 to transmit after slot n + k.

[0131] Example 15. Any one of Examples 1-14 where the number N or timer window W is implicitly determined to be at least covering (providing OD-SSBs) the same period of time as one or more of:

[0132] SCell deactivation timer;

[0133] UE C-DRX IAT; and / or

[0134] BWP IAT.

[0135] As will be appreciated by one of skill in the art, the concepts described herein may be embodied as a method, data processing system, computer program product and / or computer storage media storing an executable computer program. Accordingly, the concepts described herein may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects all generally referred to herein as a “circuit” or “module.” Any process, step,action and / or functionality described herein may be performed by, and / or associated to, a corresponding module, which may be implemented in software and / or firmware and / or hardware. Furthermore, the disclosure may take the form of a computer program product on a tangible computer usable storage medium having computer program code embodied in the medium that may be executed by a computer. Any suitable tangible computer readable medium may be utilized including hard disks, CD-ROMs, electronic storage devices, optical storage devices, or magnetic storage devices.

[0136] Some embodiments are described herein with reference to flowchart illustrations and / or block diagrams of methods, systems and computer program products. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer (to thereby create a special purpose computer), special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0137] It is to be understood that the functions / acts noted in the blocks may occur out of the order noted in the operational illustrations. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality / acts involved. Although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

[0138] Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, all embodiments may be combined in any way and / or combination, and the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or

[0139] subcombination.Example Embodiments are provided hereinafter:

[0140] Embodiment Al . A network node configured to communicate with a user equipment (UE), the network node configured to, and / or comprising a radio interface and / or comprising processing circuitry configured to:

[0141] configure the UE with an indication of an on-demand synchronization signal block (OD-SSB) activation condition; and

[0142] configure the UE to restart an OD-SSB deactivation timer when the activation condition occurs.

[0143] Embodiment A2. The network node of Embodiment Al , wherein the OD-S SB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer.

[0144] Embodiment A3. The network node of any of Embodiments Al and A2, wherein the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n.

[0145] Embodiment A4. The network node of any of Embodiments Al -A3, wherein the network, radio interface and / or processing circuitry are configured to configure the UE to maintain a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing.

[0146] Embodiment A5. The network node of any of Embodiments A1-A4, wherein a duration of an OD-SSB configured to be not less than a duration of a secondary cell (SCell) deactivation timer.

[0147] Embodiment Bl . A method implemented in a network node that is configured to communicate with a user equipment, the method comprising:

[0148] configuring the UE with an indication of an on-demand synchronization signal block (OD-SSB) activation condition; and

[0149] configuring the UE to restart an OD-SSB deactivation timer when the activation condition occurs.Embodiment B2. The method of Embodiment Bl, wherein the OD-SSB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer.

[0150] Embodiment B3. The method of any of Embodiments Bl and B2, wherein the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n.

[0151] Embodiment B4. The method of any of Embodiments B1-B3, further comprising configuring the UE to maintain a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing.

[0152] Embodiment B5. The method of any of Embodiments B1-B4, wherein a duration of an OD-SSB configured to be not less than a duration of a secondary cell (SCell) deactivation timer.

[0153] Embodiment Cl . A user equipment (UE) configured to communicate with a network node, the UE configured to, and / or comprising a radio interface and / or processing circuitry configured to:

[0154] receive from the network node an indication of an on-demand synchronization signal block (OD-SSB) activation condition; and

[0155] restart an OD-SSB deactivation timer when the activation condition occurs.

[0156] Embodiment C2. The UE of Embodiment Cl, wherein the OD-SSB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer.

[0157] Embodiment C3. The UE of any of Embodiments Cl and C2, wherein the OD-SSB deactivation timer is restarted when a medium access control (MAC) control element (CE) is received on a secondary cell (SCell).

[0158] Embodiment C4. The UE of Embodiment C3, wherein the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n.Embodiment C5. The UE of Embodiment C4, wherein the UE, radio interface and / or processing circuitry are configured to restart an SCell deactivation timer assuming that an OD-SSB is transmitted for at least a minimum number of SSB bursts after slot n+k.

[0159] Embodiment C6. The UE of any of Embodiments C1-C5, wherein the UE, radio interface and / or processing circuitry are configured to receive an indication to prolong a duration of the OD-SSB deactivation timer.

[0160] Embodiment C7. The UE of any of Embodiments C1-C6, wherein the UE is configured to maintain a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing.

[0161] Embodiment C8. The UE of any of Embodiments C1-C7, wherein a duration of the OD-SSB is not less than a duration of a secondary cell (SCell) deactivation timer.

[0162] Embodiment C9. The UE of any of Embodiments C1-C8, wherein an OD- SSB and a secondary cell (SCell) are determined to be active when either the OD-SSB deactivation timer and an secondary cell (SCell) deactivation timer are running.

[0163] Embodiment CIO. The UE of any of Embodiments C1-C9, wherein a starting point for OD-SSB retransmission is configured by the network node.

[0164] Embodiment DI . A method implemented in a user equipment (UE) that is configured to communicate with a network node, the method comprising:

[0165] receiving from the network node an indication of an on-demand synchronization signal block (OD-SSB) activation condition; and

[0166] restarting an OD-SSB deactivation timer when the activation condition occurs.

[0167] Embodiment D2. The method of Embodiment DI, wherein the OD-SSB activation condition is a condition that causes reactivation of a secondary cell (SCell) deactivation timer.Embodiment D3. The method of any of Embodiments DI and D2, wherein the OD-SSB deactivation timer is restarted when a medium access control (MAC) control element (CE) is received on a secondary cell (SCell).

[0168] Embodiment D4. The method of Embodiment D3, wherein the activation condition includes receiving an activated MAC CE indicating an OD-SSB reactivation indication in a slot, n.

[0169] Embodiment D5. The method of Embodiment D4, further comprising restarting an SCell deactivation timer assuming that an OD-SSB is transmitted for at least a minimum number of SSB bursts after slot n+k.

[0170] Embodiment D6. The method of any of Embodiments D1-D5, further comprising receiving an indication to prolong a duration of the OD-SSB deactivation timer.

[0171] Embodiment D7. The method of any of Embodiments D1-D6, further comprising maintaining a single timer for both OD-SSB deactivation timing and secondary cell (SCell) deactivation timing.

[0172] Embodiment D8. The method of any of Embodiments D1-D7, wherein a duration of the OD-SSB is not less than a duration of a secondary cell (SCell) deactivation timer.

[0173] Embodiment D9. The method of any of Embodiments D1-D8, wherein an OD-SSB and a secondary cell (SCell) are determined to be active when either the OD-SSB deactivation timer and an secondary cell (SCell) deactivation timer are running.

[0174] Embodiment DIO. The method of any of Embodiments D1-D9, wherein a starting point for OD-SSB retransmission is configured by the network node.

Claims

CLAIMS1. A method performed by a wireless device (22), WD, served by a primary cell in a wireless communication system, the method comprising:when receiving, from a secondary cell, SCell, on-demand Synchronization Signal Blocks, OD-SSBs, as an OD-SSB provision timer is running, receiving an indication of a trigger event associated with provision of OD-SSBs of the SCell; andrenewing the OD-SSB provision timer for OD-SSBs of the SCell.

2. The method of Claim 1, further comprising:in response to the trigger event, renewing or (re)starting any of:a deactivation timer of the SCell,a Connected-Discontinuous Reception, C-DRX, Inactivity Timer, IAT, associated with the SCell, and / orBandwidth Part, BWP, IAT associated with the SCell;wherein renewing the OD-SSB provision timer comprises: renewing the OD-SSB provision timer at least until any of the above timer expires.

3. The method of Claims 1 or 2, wherein the indication of the trigger event comprises any of:an SCell activation command by medium access control, MAC, control element, CE;an OD-SSB activation command by MAC CE;an MAC CE command activating both the SCell and OD-SSB; andan MAC PDU scheduling on the SCell.

4. The method of Claim 3, wherein the OD-SSB activation command by MAC CE or the MAC CE command activating both the SCell and OD-SSB comprises an indication of a number N of OD-SSB bursts to be received after a time offset, or a time window W in which OD-SSB bursts to be received after a time offset, andwherein the number N or time window W is one of a list of candidate values or timer durations configured for the WD.

5. The method of Claim 4, wherein each of the candidate values or the timer durations of the list is associated with one of a number of OD-SSB configurations configured with the WD.

6. The method of any of Claims 2 to 5, wherein when the renewing of the OD-SSB provision timer and the renewing / restarting of the SCell deactivation timer are performedat a same time, the renewed duration of the OD-SSB provision timer is longer than or equal to the renewed or restarted duration of the SCell deactivation timer.

7. The method of any of Claims 2 to 5, wherein when the SCell is active at the reception of the indication of the trigger event, the method comprising: renewing the deactivation timer of the SCell; andwhen the SCell is inactive at the reception of the indication of the trigger event, the method comprising: restarting the deactivation timer of the SCell.

8. The method of Claim 1, wherein the renewed OD-SSB provision timer also function as a deactivation timer of the SCell that the SCell is deactivated when it expires.

9. The method of any of the preceding claims, wherein SSBs received from the SCell are OD-SSBs only; and / or the indication of the trigger event is received from a primary cell of the WD, the SCell, or another SCell.

10. A method performed by a network node (16), NB, configured to communicate with a wireless device (22), WD, in a wireless communication system, the method comprising:when the WD (22) is receiving on-demand Synchronization Signal Blocks, OD- SSBs, from a secondary cell, SCell, providing an indication of a trigger event associated with provision of OD-SSBs from the SCell.

11. The method of Claim 10, wherein the trigger event comprises any of:an SCell activation command by MAC CE;an OD-SSB activation command by MAC CE;an MAC CE command activating both the SCell and OD-SSB; andan MAC PDU scheduling on the SCell.

12. The method of Claim 11, wherein the OD-SSB activation command by MAC CE or the MAC CE command activating both the SCell and OD-SSB comprises an indication of a number N of OD-SSB bursts to be transmitted after a time offset, or a time window W in which OD-SSB bursts to be transmitted after a time offset; andthe number N or time window W is one of a list of candidate values or timer durations configured for the WD.

13. The method of Claim 12, further comprising: configuring the WD with a number of OD-SSB configurations associated with the list of candidate values or timer durations respectively.

14. The method of any of Claims 10 to 13, wherein SSBs provided by the SCell consist of OD-SSBs.

15. The method of any of the Claims 10 to 14, wherein the SCell is operated by the NB, the method further comprising: providing the OD-SSBs to the UE at least until the SCell transitions from active state to inactive state; and / orthe NB operates a primary cell of the WD.

16. A wireless device (22), WD, comprising:a radio interface (46) configured to communicate with a network node;a processor (52); anda memory (54) containing instructions executable by the processor (52) whereby the WD is operative to perform the method according to any of the claims 1 to 9.

17. A network node (16), comprising:a radio interface (30) configured to communicate with a wireless device (22);a processor (38); anda memory (40) containing instructions executable by the processor (38) whereby the network node (16) is operative to perform the method according to any of the claims 10 to 15.

Images