SIB1 re-acquisition in an NES cell

Abstract

Embodiments of the present disclosure disclose a Network Energy Saving (NES) cell. The NES Cell is configured to detect an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode. The NES cell then broadcasts the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell, and transmit a paging message with SystemInfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell. Thus, the broadcast of the updated UL WUS configuration in the corresponding SIB improves energy saving of UE as UE need not perform cell reselection to cell A and removes additional signalling.

Description

SIB1 RE-ACQUISITION IN AN NES CELLCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Indian Provisional Application No. 202441057804, filed on July 30, 2024, and Indian Non-Provisional Application No. 202441057804, filed on February 28, 2025, the entire contents of which are incorporated herein by reference.FIELD

[0002] The present disclosure relates to system information block 1 (SIB1) re-acquisition in a network energy saving (NES) Cell.BACKGROUND

[0003] Network energy saving is of utmost importance for environmental sustainability, to reduce environmental impact (greenhouse gas emissions), and for operational cost savings. Cells associated with the Network Energy Saving (NES) features (also termed as NES cells) stay in dormant state or sleep state to save energy. The NES cells stay in dormant state until a wake-up signal is received. The NES cells transmit System Information Blocks (SIB) to the user terminals on receiving the wake-up signal.

[0004] 5G New Radio (NR) System Information block 1 (SIB1) carries critical information that user equipment (UE) needs to access and operate on a 5G network. The base station (gNB in 5G) broadcasts SIB1 periodically to ensure that UEs within its coverage area can access this information as per requirement. SIB1 provides essential initial information to facilitate synchronization and connection establishment. On-Demand SIB1 for UEs in idle / inactive mode refers to a feature in 5G networks where certain SIB1 can be requested on demand by the User Equipment (UE) in idle and / or inactive state. However, UEs in idle / inactive mode may require fresh SIB1 information during initial access, cell reselection, or when waking up.

[0005] In the case when a UE is camped on NES cell and the NES cell moves to Energy saving (ES) mode i.e., when periodic SIB1 and / or OD-SIB1 transmission is stopped. In such scenario, the UE has to re-acquire SIB1 of the NES cell by performing cell reselection to an anchor cell (Cell A) and re-acquire the updated Wake-Up signal (WUS) configuration of the NES cell from Cell A. This is sub-optimal as the UE may have to perform several additional steps to reacquire the SIB1, which incurs additional UE power and signaling towards the network. Thus, there is a need for an optimized solution for SIB 1 re-acquisition in the NES cell.

[0006] The information disclosed in this background section is only for enhancement of understanding of the general background of the disclosure and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.SUMMARY

[0007] Once the UE in IDLE / INACTIVE mode camps on NES cell, the UE has to reacquire SIB1 for various reasons such as cell-resel ection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT) etc. If the NES cell is transmitting OD-SIB1, then it can be assumed that the UE has the WUS configuration and hence can perform a SIB 1 re-acquisition. In case the NES cell is in Energy saving mode i.e., OD-SIB1 transmission is stopped, the most straightforward solution is that the UE is configured to perform cell reselection to cell A and reacquire WUS configuration. Subsequently, the UE sends UL Wake-up signal i.e., performs RACH procedure and triggers OD-SIB1 transmission from the NES cell. This is sub-optimal as the UE has to perform cell reselection to cell A, thereby incurring additional UE power as well as signaling towards the network.

[0008] In one non-limiting embodiment of the present disclosure, a Network Energy Saving (NES) Cell. The NES Cell is configured to detect an update in uplink (UL) wake-up signal (WUS) configuration of the NES cell, when NES cell is in energy saving (ES) mode. The NES Cell is then configured to broadcast the updated UL WUS configuration in acorresponding system information block (SIB) of the NES cell and transmit a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

[0009] In another non-limiting embodiment of the present disclosure, a method is disclosed. The method comprises detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode and broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell. The method then comprises transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

[0010] In yet another non-limiting embodiment of the present disclosure, a non-transitory computer-readable medium is disclosed. The non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of upon detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode and broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell. The computer-readable instructions when executed by the apparatus further causes the apparatus to perform transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

[0011] In yet another non-limiting embodiment of the present disclosure, a user equipment (UE) is disclosed. The UE is configured to receive a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell. The paging message indicates an on demand system information block 1 (OD SIB I) transmission to acquire anupdated uplink wake-up signal (UL WUS) configuration. The UE is then configured to reacquire modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.

[0012] In yet another non-limiting embodiment of the present disclosure, a method is disclosed. The method comprises receiving a paging message with SystemlnfoModifi cation from a Network Energy Saving (NES) Cell. The paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration. The method then comprises re-acquiring modified OD- SIB1 and the updated UL WUS configuration at least based on the paging message.

[0013] In yet another non-limiting embodiment of the present disclosure, a non-transitory computer-readable medium is disclosed. The non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of receiving a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell. The paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration. The computer-readable instructions when executed by the apparatus further causes the apparatus to perform reacquiring modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.

[0014] In yet another non-limiting embodiment of the present disclosure, a Network Energy Saving (NES) Cell. The NES Cell is configured to broadcast an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell and transmit a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode. The NES Cell is then configured to receive, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB1) transmissionbased on the updated UL WUS configuration, while in ES mode and initiate the modified OD-SIB1 transmission at least based on the received request.

[0015] In yet another non-limiting embodiment of the present disclosure, a method is disclosed. The method comprises broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell and transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode. The method then comprises receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, while in ES mode and initiating the modified OD-SIB1 transmission at least based on the received request.

[0016] In yet another non-limiting embodiment of the present disclosure, a non-transitory computer-readable medium is disclosed. The non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell and transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode. The computer-readable instructions when executed by the apparatus further causes the apparatus to perform receiving, from at least one UE, a request for modified on- demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, while in ES mode and initiating the modified OD-SIB1 transmission at least based on the received request.

[0017] In yet another non-limiting embodiment of the present disclosure, a user equipment (UE) is disclosed. The UE is configured to receive a paging message withSystemlnfoModification from Network Energy Saving (NES) Cell and receive an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB). The UE is then configured to in response to receipt of the paging message and the updated UL WUS configuration, detect at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB. The UE is then configured to request on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

[0018] In yet another non-limiting embodiment of the present disclosure, a method is disclosed. The method comprises receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell and receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB). The method then comprises in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB, and requesting on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

[0019] In yet another non-limiting embodiment of the present disclosure, a non-transitory computer-readable medium is disclosed. The non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes theapparatus to perform operations of receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell and receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB). The computer-readable instructions when executed by the apparatus further causes the apparatus to perform in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB. The computer-readable instructions when executed by the apparatus further causes the apparatus to perform requesting on demand system information block 1 (OD- SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.BRIEF DESCRIPTION OF DRAWINGS

[0020] Further embodiments and advantages of the present disclosure will be readily understood from the following detailed description with reference to the accompanying drawings. Reference numerals have been used to refer to identical or functionally similar elements. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present disclosure wherein:

[0021] FIG. 1 illustrates exemplary environment for on demand system information block 1 (OD SIB1) transmission by a network energy saving cell (NES) cell, in accordance with some embodiments of the present disclosure;

[0022] FIG. 2 illustrates a NES Cell and Anchor cell topography, in accordance with some embodiments of the present disclosure;

[0023] FIG. 3 illustrates a signaling diagram for system information block 1 (SIB1) reacquisition in a network energy saving (NES) Cell, in accordance with some embodiments of the present disclosure;

[0024] FIG. 4A shows a flowchart of a method for SIB1 re-acquisition performed at a network energy saving (NES) Cell, in accordance with some embodiments of the present disclosure

[0025] FIG. 4B shows a flowchart of a method for SIB1 re-acquisition performed at a user equipment, in accordance with some embodiments of the present disclosure;

[0026] FIG. 5A shows a flowchart of a method for S1B1 re-acquisition performed at a network energy saving (NES) Cell, in accordance with some embodiments of the present disclosure

[0027] FIG. 5B shows a flowchart of a method for SIB1 re-acquisition performed at a user equipment, in accordance with some embodiments of the present disclosure;

[0028] FIG. 6 shows a diagram of example components of NES cell / UE for SIB reacquisition, in accordance with embodiments of the present disclosure;DETAILED DESCRIPTION

[0029] The following detailed description of example embodiments refers to the accompanying drawings. The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the implementations. Further, one or more features or components of one embodiment may be incorporated into or combined with another embodiment (or one or more features of another embodiment). Additionally, the flowchart and description ofoperations provided below relate to one of the various embodiments. It should be noted that it is possible to make other embodiments that do not exactly match the flowchart and its description. It is understood that in other embodiments one or more operations may be omitted, one or more operations may be added, one or more operations may be performed simultaneously (at least in part).

[0030] It will be apparent that systems and / or methods, described herein, may be implemented in different forms of hardware, software, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and / or methods is not limiting of the implementations. Thus, the operation and behavior of the systems and / or methods are described herein without reference to specific software code. It is understood that software and hardware may be designed to implement the systems and / or methods based on the description herein.

[0031] Even though particular combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of implementations. In fact, many of these features may be combined in ways not specifically recited in the claims and / or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of implementations includes each dependent claim in combination with every other claim in the claim set.

[0032] No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Also, as used herein, the terms “has,” “have,” “having,” “include,” “including,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Furthermore, expressions such as “at least one of [A] and [B],” “[A] and / or [B],” or “at least one of [A] or [B]” are to be understood as including only A, only B, or both A and B

[0033] The foregoing disclosure provides illustration and description but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the implementations.

[0034] It shall be noted that, for convenience of explanation, the disclosure uses terms and names defined in the 3rd Generation Partnership Project Radio Access Network (3GPP RAN) standards. More specifically, the terminology on-demand system information block 1 (OD-SIBl), Random Access Channel (RACH) Request, RRC Connected UEs, Idle / Inactive UEs, Physical Downlink Control Channel (PDCCH) order, Physical Cell Identifier (PCI), are to be interpreted as specified by the 3GPP RAN standards.

[0035] The terminology “wake up signal configuration”, “WUS configuration data” and “WUS config” have same meaning and are alternatively used throughout the specification. The terminology “uplink wakeup signal”, “wake up signal”, “UL WUS”, “WUS”, and “RACH Request” have same meaning and are alternatively used throughout the specification. The terminology “anchor cell” and “Cell A” have same meaning and are alternatively used throughout the specification.

[0036] The user equipment (UE) needs to perform cell reselection to cell A and acquire updated WUS configuration of network energy saving (NES) cell, due to reasons such as return from out of coverage, upon receiving request (e.g., a positioning request) from upper layers; and whenever the UE does not have a valid version of a stored SIB or posSIB or a valid version of a requested SIB.

[0037] The present disclosure describes a system information block 1 (SIB 1) re-acquisition in a NES cell. A given NES cell’s WUS configuration is considered to be valid until the UEs are explicitly notified to re-acquire an updated SIB1 by the network. Whenever WUS configuration of the NES cell is modified by NES cell and the cell is in energy saving (ES) mode, the NES cell starts OD-SIBl broadcast proactively (i.e., deactivate ES mode) andissues a Paging message including SystemlnfoModification to IDLE / INACTIVE UEs camped on it. This triggers the UEs to re-acquire the modified SIB 1. This way, the UEs who already have WUS configuration of the NES cell initially acquired from Cell A SIB before camping on NES cell don’t have to go back to Cell A to re-acquire NES cell WUS configuration. The UEs can rely on the SystemlnfoModification Paging from NES cell, whenever WUS configuration is updated / modified. Therefore, whenever a UE has to reacquire SIB 1 of the NES cell due to UE-specific reasons mentioned above, the updated NES cell WUS configuration is always available at the UE and hence OD-SIB1 can be requested.

[0038] Further, whenever the NES cell goes to ES mode, the NES cell sends a SystemlnfoModification Paging message to all the IDLE / INACTIVE UEs of the NES cell before going to ES mode. This is to trigger the UEs to acquire WUS configuration from NES cell SIB, if they need to do so for various reasons (e g., not stored). This is optionally performed by those UEs that need the UL WUS configuration. The value tag in the SIB1 may indicate the UE, whether or not the SIB1 has been modified compared to the version that is with the UE. The UEs shall also be notified that the WUS configuration thus acquired shall remain valid unless explicitly notified using a SystemlnfoModification Paging message. This facilitates the UEs to acquire NES cell SIB1 without overhead. The system information block 1 (SIB1) re-acquisition in NES cell is explained in detail with reference to FIGS. 1-6.

[0039] FIG. 1 illustrates an exemplary environment 100 for on demand system information block 1 (OD SIB1) transmission by a network energy saving cell (NES) cell, in accordance with some embodiments of the present disclosure.

[0040] In an embodiment of the present disclosure, the environment 100 may comprise an anchor cell or cell A 110, a NES cell 103, and a user equipment (UE) 101. The example FIG. 1 refers to the “UE”. However, it should be understood by those skilled in the art that general terms such as “user device,” “terminal,” “terminal device,” “communication device,” and “communication terminal” can be used interchangeably with the term “UE.”

[0041] For example, the UE 101 may include a computing device (e.g., a desktop computer, a laptop computer, a tablet computer, a handheld computer, a smart speaker, a server, etc.), a mobile phone (e.g., a smart phone, a radiotelephone, etc.), a wearable device (e.g., a pair of smart glasses or a smart watch), or a similar device.

[0042] As shown in FIG. 1, the UE 101 may be initially in an idle or inactive mode and is camped on to the Cell A 110. The UE 10 may measure Reference Signal Received Power (RSRP) and / or Reference Signal Received Quality (RSRQ) of the NES cell 103. The UE may acquire UL WUS configuration of the NES cell from the Cell A SIB. If the RSRP and / or the RSRQ of the NES cell meets the respective threshold criteria, then the UE 101 may trigger the transmission of on-demand (OD) System Information Block Type 1 (S1B1) by sending an uplink wake up signal (UL WUS).

[0043] In one non-limiting embodiment, the UE 101 may access a minimum information block (MIB) indicating whether a NES cell is accessible to a UE or barred. If the MIB indicates that the NES cell 103 is not accessible to the UE 101, then UE 101 does not transmit the uplink WUS to the NES cell. In such scenario, the UE 101 remains coupled with the Cell A 110. The MIB also indicates whether a cell is transmitting periodic SIB1. Based on this and the cell barring information, the UE may procure the UL WUS configuration and send a UL WUS signal to request OD-SIB1 transmission.

[0044] The SIB1 contains essential information that the UE 101 needs to initially access the network, such as cell identity, network access parameters, and initial configuration details, etc. Further, this signal utilizes existing channels or signals of the network infrastructure. However, the SIB1 is not restricted to above parameters and may comprise any other parameter required for network, which is known to a person skilled in the art.

[0045] In an embodiment, the configuration details for the uplink WUS of the NES cell 103 may be initially provided to the UE 101 in the Cell A SIB. This ensures that UE 101 receives and understands how to initiate the uplink WUS for the NES cell 103.

[0046] If the NES cell 103 is in Energy Saving (ES) mode (i.e., periodic SIB1 and / or OD- SIB1 transmission is not being transmitted), the UE 101 may have to perform cell reselection to Cell A 110 on which the UE 101 camps to reacquire the latest WUS configuration of the NES cell 103. The WUS configuration of the NES cell 103 may be modified and hence needs to be re-acquired.

[0047] The above method for OD-SIB1 re-acquisition is considered sub-optimal as the UE 101 has to perform cell reselection to cell A all over again, which incurs additional UE power and signaling towards the network, when the NES cell 103 has an overlapping coverage with the Cell A 110.

[0048] The present disclosure describes a system information block 1 (SIB1) re-acquisition in the NES cell 103. Whenever WUS configuration of the NES cell 103 is modified by NES cell 103 and the NES cell 103 is in energy saving (ES) mode, the NES cell 103 starts OD- SIB1 broadcast proactively (i.e., deactivate ES mode) and issues a paging message including SystemlnfoModification to IDLE / INACTIVE UE 101 camped on it. This triggers the UE 101 to re-acquire the modified SIB1. This way, the UE 101 who already have WUS configuration of the NES cell 103 initially acquired from Cell A’s SIB before camping on NES cell don’t have to go back to Cell A 110 to re-acquire NES cell WUS configuration. The UEs can rely on the SystemlnfoModification Paging from NES cell 103, whenever WUS configuration is updated / modified.

[0049] FIG. 2 illustrates a NES Cell and Anchor cell topography, in accordance with some embodiments of the present disclosure.

[0050] FIG. 2 depict anchor cell i.e., Cell A that is defined by a significant coverage area within the cellular network. This Cell A serves as a primary reference point for managing mobility and ensuring continuous service for connected UE. Within the coverage area of the Cell A, there may be a number of Network Energy Saving (NES) cells (NES cell 1 and NES cell 2).

[0051] In a network scenario, where there is partial overlap between NES cells and the anchor cell as shown in FIG. 2, the UE in idle or inactive mode within the NES cell 2 coverage can initiate SIB1 transmission by sending an uplink wake up signal to the NES cell 2. In such a scenario, the UEs may receive the SIB1 broadcast from the NES cell 2, depending on the location of the UE and signal strength received by the UE. The SIB1 reacquisition in the NES cell is discussed in detail in below embodiments.

[0052] FIG. 3 illustrates a signaling diagram for system information block 1 (SIB1) reacquisition in a network energy saving (NES) cell, in accordance with some embodiments of the present disclosure.

[0053] In an embodiment of the present disclosure, the signaling diagram 300 includes a plurality of UEs 330, a NES cell 320, and a Cell A 310. The plurality of UEs 330 may be initially camped to the Cell A 310. In an embodiment, the NES cell 320 and the Cell A 430 may be serviced by same gNB. In another embodiment, the NES cell 320 and the Cell A 310 are serviced through different gNBs.

[0054] Initially, the plurality of UEs 330 may acquire wake up signal (WUS) configuration of NES Cell 320 from the Cell A 310 using the system information block (SIB) of Cell 310 (as shown in step SI). Then, the plurality of UEs 330 may be configured to store the WUS) configuration of NES Cell 320 (as shown in step S2).

[0055] The UEs 330 may send a Random-Access Channel (RACH) request to the NES cell 320. The RACH request is the WUS to request OD-SIB1 transmission (as shown in step S3). The SIB1 transmission may be used by the UEs 330 for camping to NES cell 320.

[0056] In response to the RACH request, the NES cell 320 may be configured to initiate the OD-SIB1 transmission (as shown in step S4). The SIB1 may contain essential information that the UE 101 needs to initially access the network, such as cell identity, network access parameters, and initial configuration details, etc. Further, this signal utilizes existing channels or signals of the network infrastructure. However, the SIB1 is not restricted to above parameters and may comprise any other parameter required for network, which is known to a person skilled in the art.

[0057] The UEs 330 in IDLE / INACTIVE mode may be camped on to the NES cell 320, using the necessary information present in the SIB1 (as shown in step S5). If the NES cell 320 is still transmitting periodic SIB1 and / or OD-SIB1, it may be assumed that the UEs 330 may perform SIB1 re-acquisition, when required.

[0058] In an embodiment, changes in SIB 1 may occur also when the NES cell is in energy savings (ES) mode, the change in SIB1 may be referred to as updates or modifications in the network. These changes may have to be broadcast to the UE 330. The NES cell 320 may be configured to relinquish the ES mode temporarily and transmit a paging message for the changed SIB1. The paging message may comprise SystemlnfoModification for the UEs 330 (as shown in step S5).

[0059] The UEs 330 may acquire the modified SIB1 of the NES cell 320, which is broadcasted by the NES cell 320 (as shown in step S7). The UEs 330 may remain camped on the NES cell 320 and the NES cell 320 may turn on energy saving (ES) mode (as shown in step S8).

[0060] While, the NES cell 320 is in ES mode and there is change in WUS configuration of the NES cell 320. The NES cell 320 may be configured o turn-off the ES mode and switch to non-ES mode. Then, the NES cell 320 may initiate OD-SIB1 transmission (as shown in step S9).

[0061] Then, the NES cell 320 may be configured to transmit a paging message to the UEs 330. The paging message may comprise SystemlnfoModification for the UEs 330 (as shown in step S10). The paging message indicates that they have to acquire the updated WUS configuration of the NES cell 320 to the IDLE / INACTIVE UEs 330.

[0062] The NES cell 320 may be configured to transmit OD-SIB1 transmission (as shown in step Si l). The UEs 330 may acquire updated WUS configuration of the NES cell 320 along with modified SIBl(as shown in step S12).

[0063] The UEs 330 may store the updated WUS configuration for requesting OD-SIB1, whenever needed(as shown in step S12). This facilitates the UEs to acquire NES cell SIB1 without overhead. Thus, the UEs 330 may need not perform cell reselection to Cell A for acquire updated WUS configuration of NES.

[0064] In an embodiment, the above discussed technique for SIB1 re-acquisition in the NES cell could potentially reduce unnecessary cell reselections, thereby improving the network’s efficiency. Furthermore, these disclosed techniques might also decrease the additional power used by the UE for cell reselection, as well as reduce signaling towards the network.

[0065] Referring now to FIG. 4A, which shows a flowchart of a method for SIB1 reacquisition performed at a network energy saving (NES) Cell. The method 400a is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover network energy saving (NES). In one non-limiting embodiment, the method 400a maybe performed by NES cell. In another non-limiting embodiment, the method 400a may be performed by the gNB or a NG-RAN node of the NES cell.

[0066] The method 400a may comprise, at block 401a, detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode. The WUS configuration of the NES Cell may change due to network condition. The NES cell may switch back to non-energy saving (non-ES) mode, in response to detection of the change in UL WUS configuration.

[0067] The method 400a may comprise, at block 403a, broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell. The UL WUS configuration may be required by the UE to transmit the uplink wake up signal to the NES cell.

[0068] The method 400a may comprise, at block 405a, transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell. The paging message may be used to inform about a modified on-demand SIB 1 (OD- SIB1) transmission from the NES cell. The paging message may be transmitted in response to detection of the update in UL WUS configuration of the NES Cell. The paging message indicates the updated WUS configuration of the NES cell to the IDLE / INACTIVE UEs.

[0069] In an embodiment, the method 400a may further comprise transmitting modified OD-SIB1 to the IDLE / INACTIVE UEs. The modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.

[0070] Thus, the transmission of modified SIB1 and updated WUS configuration of the NES cell facilitates potential reduction in unnecessary cell reselections, thereby improving the network’s efficiency. Furthermore, the method 400a also decreases the additional power used by the UE for cell reselection, as well as reduce signaling towards the network.

[0071] Referring now to FIG. 4B, which illustrates a flowchart of a method for SIB1 reacquisition performed at a user equipment. The method 400b is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover network energy saving (NES). In one non-limiting embodiment, the method 400b may be performed by a user equipment (UE).

[0072] The method 400b may comprise, at block 401b, receiving a paging message with SystemlnfoModifi cation from a Network Energy Saving (NES) Cell. The paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration.

[0073] The method 400b may comprise, at block 403b, re-acquiring modified OD-S B1 and the updated UL WUS configuration at least based on the paging message. The modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.

[0074] In an embodiment, the re-acquiring of the modified OD-SIB1 may comprise detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB. The re-acquiring of the modified OD-SIB1 may further comprise requesting OD-S1B1 transmission at least based on the updated UL WUS configuration and receiving the modified OD-SIB1 based on the requested OD-SIB1 transmission.

[0075] In an embodiment, the method 400b may further comprise storing the updated UL WUS configuration of the NES Cell. The updated UL WUS configuration of the NES Cell may be used by the UE for requesting OD-SZB1, whenever needed.

[0076] The reception of the updated WUS configuration of the NES cell facilitates potential reduction in unnecessary cell reselections to Cell A, thereby improving the network’s efficiency. Furthermore, the method 400b also decrease the additional power used by the UE for cell reselection, as well as reduce signaling towards the network.

[0077] Referring now to FIG. 5A, which shows a flowchart of a method for SIB1 reacquisition performed at a network energy saving (NES) Cell. The method 500a is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover network energy saving (NES). In one non-limiting embodiment, the method 500a may be performed by NES cell. In another non-limiting embodiment, the method 400a may be performed by the gNB or a NG-RAN node of the NES cell.

[0078] The method 500a may comprise, at block 501a, broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell. The WUS configuration of the NES Cell may change due to network condition. The NES cell may transmit the UL WUS configuration before switching to ES mode.

[0079] The method 500a may comprise, at block 503a, transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode. The paging message may indicate the at least one UE to re-acquire OD-SIB1 and access the updated UL WUS configuration.

[0080] The method 500a may comprise, at block 505a, receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, while in ES mode. The method 500a may comprise, at block 507a, initiating the modified OD-SIB1 transmission at least based on the receivedrequest. The modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell

[0081] In an embodiment, the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

[0082] Thus, the transmission of modified SIB1 and updated WUS configuration of the NES cell facilitates potential reduction in unnecessary cell reselections, thereby improving the network’s efficiency. Furthermore, the method 500a also decrease the additional power used by the UE for cell reselection, as well as reduce signaling towards the network.

[0083] Referring now to FIG. 5B, which illustrates a flowchart of a method for SIB1 reacquisition performed at a user equipment. The method 500b is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover network energy saving (NES). In one non-limiting embodiment, the method 500b may be performed by a user equipment (UE).

[0084] The method 500b may comprise, at block 501b, receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell. The paging message indicates an on demand system information block 1 (OD STB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration.

[0085] The method 500b may comprise, at block 503b, receiving an updated uplink wakeup signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB).

[0086] The method 500b may comprise, at block 505b, in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, afterreconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB.

[0087] The method 500b may comprise, at block 507b, requesting on demand system information block 1 (OD-SIBl) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition. The requesting the SIB1 may comprise transmitting a request for OD-SIB 1 transmission to the NES Cell based on the UL WUS configuration of the NES Cell and receiving modified OD-SIBl from the NES Cell based on the transmitted request.

[0088] In an embodiment, the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

[0089] The reception of the updated WUS configuration of the NES cell facilitates potential reduction in unnecessary cell reselections to Cell A, thereby improving the network’s efficiency. Furthermore, the method 500b also decrease the additional power used by the UE for cell reselection, as well as reduce signaling towards the network.

[0090] FIG. 6 illustrates an embodiment of a NES cell 600, or a gNB of a NES cell 600. As shown in FIG. 6, the NES cell 600 comprises a processor 610, a memory 620, a storage component 630, an input component 640, an output component 650, a communication interface 660, and a bus 670. In one non-limiting embodiment, a user equipment (UE) may comprise similar set of components for performing the above mentioned functionality.

[0091] The processor 610, as used herein, means any type of computational circuit that may comprise hardware elements and software elements. The processor 610 may be embodied as a multi-core processor, a single core processor, or a combination of one or more multi-core processors and / or one or more single core processors, a distributed processing system, or the like. The processor 610 may be a Central Processing Unit (CPU) a graphics processing unit (GPU), an accelerated processing unit (APU), an applicationspecific integrated circuit (ASIC), or another type of processing component.

[0092] The memory 620 includes a non-transitory computer readable medium. Memory 620 includes a random-access memory (RAM), a read only memory (ROM), and / or another type of dynamic or static storage device (e.g., a flash memory, a magnetic memory, and / or an optical memory) that stores information and / or instructions for use by processor 610. The memory 620 comprises machine-readable instructions which are executable by the processor 610. These machine-readable instructions when executed by the processor 610 cause the processor 610 to perform one or more method steps of an embodiment described above.

[0093] The storage component 630 stores information and / or software related to the operation and use of the NES cell 600. For example, the storage component 630 may include a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, and / or a solid-state disk), a compact disc (CD), a digital versatile disc (DVD), a floppy disk, a cartridge, a magnetic tape, and / or another type of non-transitory computer-readable medium, along with a corresponding drive.

[0094] The input component 640 is configured to receive information, such as user input. For example, the input component 640 may include, but not be limited to, a touch screen display, a keyboard, a keypad, a mouse, a button, a switch, and / or a microphone. Additionally, or alternatively, the input component 640 may include a sensor for sensinginformation (e.g., a global positioning system (GPS), an accelerometer, a gyroscope, and / or an actuator).

[0095] The output component 650 is configured to provide output information from the NES cell 600. For example, the output component 650 may be, but not limited to, a display, a speaker, instructions to an external device, and / or one or more light-emitting diodes (LEDs).

[0096] The communication interface 660 is an interface that provides a communication connection to other devices, such as external devices and internal devices. The connection by the communication interface 660 can be a wired connection, a wireless connection, or a combination of wired and wireless connections, and can be a direct connection or an indirect connection via a communication network that exists between the NES cell 600 and other devices. In other words, the standard of the communication interface 660 is not limited.

[0097] The bus 670 acts as an interconnect between the processor 610, the memory 620, the storage component 630, the input component 640, the output component 650, and the communication interface 660 of the NES cell 600. The bus 670 may include a wired interconnection or a wireless interconnection.

[0098] The number and arrangement of components shown in FIG. 6 are provided as an example. In practice, the NES cell 600 may include additional components, fewer components, different components, or differently arranged components than those shown in FIG. 6. Additionally, or alternatively, a set of components (e.g., one or more components) of the NES cell 600 may perform one or more functions described as being performed by another set of components of the NES cell 600. Further, one or more method steps described in any of the embodiments may be performed utilizing a plurality of NES cells 600 in communication with one another.Additional Description:

[0099] 1. IntroductionThe Rel-19 WI on enhancements of network energy savings for NR (RP -234065) includes the objective to study on-demand SIB1 for idle / inactive UEs as mentioned below:Study procedures and signaling method(s) to support on-demand SIB1 for UEs in idle / inactive mode, including: [RAN1 / 2 / 3]• Triggering method by uplink wake-up-signal using an existing signal / channel.• Wake-up-signal configuration provisioning to UE o Note: No modification of SSB will be discussed under this objective• Information exchange between gNBs at least for the configuration of wake-up signal, if necessary.• Checkpoint for normative work in RAN# 105The present disclosure discusses some important aspects associated with OD-SIB1, focussed on the highlighted objective.

[0100] 2. DiscussionIn this disclosure, the following nomenclature is referred.The gNB associated with the NES cell as NES cell gNBThe gNB-CU associated with the NES cell as NES cell gNB-CUThe gNB-DU associated with the NES cell as NES cell gNB-DUThe gNB associated with the Cell A as Cell A gNBThe gNB-CU associated with the Cell A as Cell A gNB-CUThe gNB-DU associated with the Cell A as Cell A gNB-DU

[0101] 2.1 IntroductionRAN1#116 (February 2024) made the following assumptions for the purpose of discussion:For discussion purpose, the following assumption will be used in RANI• Cell A: A cell that is periodically transmitting at least its own SIB 1.• NES Cell: A cell that may transmit SIB1 transmission in response to UL WUS from a UEThe cell A in the below example is a macro cell and the NES cell is a small cell which has at least partial overlapping coverage with the macro cell.

[0102] 2.2 IDLE / INACTIVE mode overload in Cell AWhen an overload condition is detected in Cell A with respect to IDLE / INACTIVE mode UEs, a percentage of IDLE / INACTIVE UEs have to be offloaded to the NES cells. Further, all new UEs coming to Cell A have to be re-directed to the NES cells until the overload condition eases. When the IDLE / INACTIVE UEs overload condition is detected, the anchor cell gNB shall offload UEs to one or more NES cells having overlapping coverage with it, an exemplary topography of anchor cell with overlapping NES cell(s) is shown in FIG. 2.Proposal 1: When an overload condition of IDLE / INACTIVE UEs is detected in Cell A, the Cell A gNB shall initiate offloading of IDLE / INACTIVE UEs to NES cells.To execute this offloading, the Cell A modifies its SIB1 to include the list of NES cell IDs to which offloading is intended. In addition to this, the cause “Overload Based Offloading” may also be indicated, so that the UEs can transmit a UL WUS to the NES cell and perform cell-reselection to NES cell after acquiring UL WUS configuration. Cell A gNB sends a Paging with System Info Modification to all UEs camped on it to read SIB1 modification. This enables the UEs to read the modified Cell A SIB1 and evaluate the radio condition of NES cell and perform cell re-selection to NES cell, if feasible. Alternatively, if the Cell A gNB wants to take proactive action to just prevent new incoming UEs, it could send a backhaul signaling to the NES cell gNB to initiate OD-SIB1 transmission, so that all the incoming UEs could directly camp on the NES cell without coming to Cell A.Proposal 2: During overload, Cell A gNB initiates a Paging message with System Info Modification to trigger camped UEs to read modified SIB1 and transmit UL WUS and perform cell re-selection to NES cell.Proposal 3: The Paging message with modified SIB1 may include the list of NES Cell IDs selected for offloading UEs and the cause.Proposal 4: Cell A gNB may request NES cell gNB to trigger OD-SIB1 transmiss ion without a UL WUS. RAN2 asks RAN3 to discuss and agree a solution to handle this issue.[00103J 2.3 SIB1 reacquisition in an NES cellOnce a UE in IDLE / INACTIVE mode camps on NES cell, it may have to re-acquire SIB1 for reasons mentioned below.RRC TS 38.331:5.2.2.2 SIB validity and need to (re)-acquire SIB5.2.2.2.1 SIB validityThe UE shall apply the SI acquisition procedure as defined in clause 5.2.2.3 upon cell selection (e.g. upon power on), cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another RAT, upon receiving an indication that the system information has changed, upon receiving a PWS notification, upon receiving request (e.g., a positioning request) from upper layers; and whenever the UE does not have a valid version of a stored SIB or posSIB or a valid version of a requested SIB.It is observed that UEs might need to reacquire SIB1 under certain circumstances as mentioned above.Observation 1: UEs might need to reacquire SIB1 of an NES cell after having camped there.If the NES cell is transmitting OD-SIB1, then it can be assumed that the UE can perform a SIB1 re-acquisition. In case the NES cell is in Energy saving mode i.e., there is no periodic SIB transmission or OD-SIB1 transmission is stopped, then the most straightforwardsolution for UEs to reacquire SIB1 is to perform cell reselection to cell A where it can reacquire NES Cell UL WUS configuration. Subsequently it sends UL WUS to NES cell i.e., performs RACH procedure and requests OD-SIBl transmission from the NES cell. Thus it can re-acquire the latest SIB1. This is sub-optimal as the UE has to perform cell reselection to cell A all over again. It incurs additional UE power as well as signaling towards the network.Observation 2: For a UE camped on NES cell, it is suboptimal to perform cell re-selection to Cell A to acquire UL WUS configuration of NES cell, request NES cell to transmit OD- SIBl again and re-acquire SIB1 of NES cell.Instead, the UL WUS configuration of an NES cell could be considered to be valid until explicitly indicated. This implies that whenever the UL WUS configuration of an NES cell is modified when the NES cell is in ES mode, the NES cell initiates OD-SIBl broadcast proactively (i.e., deactivates ES mode) and sends a Paging message with System Info Broadcast to IDLE / INACTIVE UEs camped on it. This triggers the camped UEs to acquire the UL WUS configuration from the NES cell itself. Further, the UEs may use the UL WUS to re-acquire SIB1 whenever required.Proposal 5: UL WUS configuration of a NES cell acquired by a UE is considered valid unless explicitly indicated to the UE.Proposal 6: Whenever an NES cell is in non-ES mode, the NES cell broadcasts its own UL WUS configuration in its SIBl.Proposal 7: Whenever there is a modification in the UL WUS configuration of the NES cell, the NES cell proactively initiates OD-SIBl transmission and sends a Paging message with System Info Broadcast to all IDLE / INACTIVE UEs.

[0104] 2.4 Synergizing OD-SIBl transmission in an NES cellOD-SIBl transmission is based on UL wake-up signal directly sent to NES cell (or via Cell A) from individual UEs and there could be multiple UEs in the coverage area of an NES cell who are eligible to camp on the NES cell, waiting for OD-SIBl transmission.NES cell triggering 0D-SIB1 transmission per UE is sub-optimal from energy savings perspective. Moreover, the other eligible UEs in IDLE / INACTIVE mode are not aware of OD-SIB1 transmission, as they may not try to perform cell re-selection at the same time.Observation 3: NES cell triggering OD-SIB1 transmission per UE is sub-optimal from energy savings perspective.Observation 4: Eligible UEs in IDLE / INACTIVE mode which are camped on Cell A are not aware of NES cell’s OD-SIB1 transmission.To mitigate this, the NES cell may decide when to start the OD-SIB1 transmission. For example, the gNB could configure a threshold number of “n” UEs requesting OD-SIB1, before initiating OD-SIB1 transmission, i.e., the OD-SIB1 transmission could be initiated only after ‘n’ UEs have sent UL wake-up signal to the NES cell.In such a case where the INES is not going to start the OD-SIB1 transmission immediately upon receiving the UL WUS, the gNB may indicate to the UE, for example in the Random Access Response(RAR), that the UE need not monitor PDCCH in the RAR-window. The UE may also implicitly understand that the network will communicate whenever OD-SIB1 transmission is initiated.Proposal 8: gNB shall be able to be configured to wait until a threshold number of “n” UEs request OD-SIB1 before initiating OD-SIB1 transmission in an NES cell.Proposal 9: Post receiving a UL WUS request, the gNB shall be able to indicate to the UE to not monitor PDCCH in the RAR-window, when the OD-SIB 1 transmission is not initiated immediately.Subsequently, when the ‘n’ number of UL WUS requests are received, the gNB may initiate the OD-SIB 1 transmission at the NES cell. Since the intention is to inform all the eligible UEs (including those that have already sent a UL WUS requesting OD-SIB 1 earlier), the NES cell gNB has to notify the cell A gNB to notify the IDLE / INACTIVE UEs camped on cell A, so that they can access the OD-SIB 1 transmission.Proposal 10: The NES cell gNB shall notify the Cell A gNB about the NES Cell ID and its OD-SIB 1 transmission. RAN2 asks RAN3 to discuss and agree a way forward for this issue.Proposal 11 : The Cell A gNB shall send a Paging message to all the IDLE / IN ACTIVE UEs to inform them about the NES Cell ID and its OD-SIB1 transmission.Proposal 12: The IDLE / INACTIVE UEs on Cell A, who already have the WUS configuration of the given NES cell, may access OD-SIB1 of NES cell and perform cell reselection to NES cell.[00105J 3. ConclusionIn summary, following are observations:Observation 1 UEs might need to reacquire SIB1 of an NES cell after having camped there.Observation 2 For a UE camped on NES cell, it is suboptimal to perform cell re-selection to Cell A to acquire UL WUS configuration of NES cell, request NES cell to transmit OD- SIB1 again and re-acquire SfBl of NES cell.Observation s NES cell triggering OD-SIB1 transmission per UE is sub-optimal from energy savings perspective.Observation 4 Eligible UEs in IDLE / INACTIVE mode which are camped on Cell A are not aware of NES cell’s OD-SIB1 transmission.In summary, following are the proposals:Proposal 1 When an overload condition of IDLE / INACTIVE UEs is detected in Cell A, the Cell A gNB shall initiate offloading of IDLE / INACTIVE UEs to NES cells.Proposal 2 During overload, Cell A gNB initiates a Paging message with System Info Modification to trigger camped UEs to read modified SIB1 and transmit UL WUS and perform cell re-selection to NES cell.Proposal 3 The Paging message with modified S1B1 may include the list of NES Cell IDs selected for offloading UEs and the cause.Proposal 4 Cell A gNB may request NES cell gNB to trigger OD-SIB1 transmission without a UL WUS. RAN2 asks RANT to discuss and agree a solution to handle this issue.Proposal 5 UL WUS configuration of an NES cell acquired by a UE is considered valid unless explicitly indicated to the UE.Proposal 6 Whenever an NES cell is in non-ES mode, the NES cell broadcasts its own UL WUS configuration in its SIB1.Proposal 7 Whenever there is a modification in the UL WUS configuration of the NES cell, the NES cell proactively initiates OD-SIB1 transmission and sends a Paging message with System Info Broadcast to all IDLE / IN ACTIVE UEs.Proposal 8 gNB shall be able to be configured to wait until a threshold number of “n” UEs request OD-SIB1 before initiating OD-SIB1 transmission in an NES cell.Proposal 9 Post receiving a UL WUS request, the gNB shall be able to indicate to the UE to not monitor PDCCH in the RAR-window, when the OD-SIB1 transmission is not initiated immediately.Proposal 10 The NES cell gNB shall notify the Cell A gNB about the NES Cell ID and its OD-SIB1 transmission. RAN2 asks RAN3 to discuss and agree a way forward for this issue.Proposal 11 The Cell A gNB shall send a Paging message to all the IDLE / INACTIVE UEs to inform them about the NES Cell ID and its OD-SIB1 transmission.Proposal 12 The IDLE / INACTIVE UEs on Cell A, who already have the WUS configuration of the given NES cell, may access OD-SIB1 of NES cell and perform cell re-selection to NES cell.

[0106] The present disclosure may further include below embodiments:Embodiment 1. A Network Energy Saving (NES) Cell configured to: detect an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode; broadcast the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; andtransmit a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.Embodiment 2. The NES Cell of embodiment 1, wherein the paging message indicates the updated WUS configuration of the NES cell to the IDLE / INACTIVE UEs.Embodiment 3. The NES Cell of embodiment 1, further configured to: transmit modified OD-SIB1 to the IDLE / INACTIVE UEs.Embodiment 4. A user equipment (UE) configured to: receive a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquire modified OD-SIB 1 and the updated UL WUS configuration at least based on the paging message.Embodiment 5. The UE of embodiment 4, wherein the modified OD-SIB 1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.Embodiment 6. The UE of embodiment 5, configured to: store the updated UL WUS configuration of the NES Cell.Embodiment 7. The UE of embodiment 4, wherein to re-acquire the modified OD-SIB 1, the UE is configured to: detect at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification,upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; request OD-SIB 1 transmission at least based on the updated UL WUS configuration; and receive the modified OD-SIB 1 based on the requested OD-SIB 1 transmission.Embodiment 8. A Network Energy Saving (NES) Cell configured to: broadcast an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmit a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode; receive, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB 1) transmission based on the updated UL WUS configuration, while in ES mode; and initiate the modified OD-SIB 1 transmission at least based on the received request.Embodiment 9. The NES Cell of embodiment 8, wherein the paging message indicates the at least one UE to re-acquire OD-SIB 1 and access the updated UL WUS configuration.Embodiment 10. The NES Cell of embodiment 8, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.Embodiment I L A user equipment (UE) configured to: receive a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell; receive an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB);in response to receipt of the paging message and the updated UL WUS configuration, detect at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and request on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.Embodiment 12. The UE of embodiment 11, wherein to request the SIB1, the UE is configured to: transmit a request for OD-SIB1 transmission to the NES Cell based on the WUS configuration of the NES Cell; and receive modified OD-SIB1 from the NES Cell based on the transmitted request.Embodiment 13. The UE of embodiment 11, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.Embodiment 14. A method performed by a Network Energy Saving (NES) Cell, the method comprising: detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode; broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; and transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.Embodiment 15. The method of embodiment 14, wherein the paging message indicates the updated WUS configuration of the NES cell to the IDLE / INACTIVE UEs.Embodiment 16. The method of embodiment 14, further comprising: transmitting modified OD-SIB1 to the IDLE / INACTIVE UEs.Embodiment 17. A method performed by a user equipment (UE), the method comprising: receiving a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquiring modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.Embodiment 18. The method of embodiment 17, wherein the modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.Embodiment 19. The method of embodiment 18, further comprising: storing the updated UL WUS configuration of the NES Cell.Embodiment 20. The method of embodiment 17, wherein re-acquiring the modified OD- SIB1 comprising: detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; requesting OD-SIB1 transmission at least based on the updated UL WUS configuration; andreceiving the modified OD-SIB1 based on the requested OD-SIB1 transmission.Embodiment 21. A method performed by a Network Energy Saving (NES) Cell, the method comprising: broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode; receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, while in ES mode; and initiating the modified OD-SIB1 transmission at least based on the received request.Embodiment 22. The method of embodiment 21, wherein the paging message indicates the at least one UE to re-acquire OD-SIB1 and access the updated UL WUS configuration.Embodiment 23. The method of embodiment 21, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.Embodiment 24. A method performed by user equipment (UE), the method comprising: receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell; receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB); in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that systeminformation (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and requesting on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.Embodiment 25. The method of embodiment 24, wherein requesting the SIB1, the UE is configured to: transmitting a request for OD-SIB1 transmission to the NES Cell based on the WUS configuration of the NES Cell; and receiving modified OD-SIB1 from the NES Cell based on the transmitted request.Embodiment 26. The method of embodiment 24, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.Embodiment 27. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: detecting an update in uplink (UE) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode; broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; and transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.Embodiment 28. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: receiving a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquiring modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.Embodiment 29. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode; receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, while in ES mode; and initiating the modified OD-SIB1 transmission at least based on the received request.Embodiment 30. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell; receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB);in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and requesting on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

Claims

WE CLAIM1. A Network Energy Saving (NES) Cell configured to: detect an update in uplink (UL) wake-up signal (WUS) configuration of the NES cell, when NES cell is in energy saving (ES) mode; broadcast the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; and transmit a paging message with SystemlnfoModification to ZDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

2. The NES Cell of claim 1, wherein the paging message indicates the updated WUS configuration of the NES cell to the IDLE / INACTIVE UEs.

3. The NES Cell of claim 1, further configured to: transmit modified OD-SIB1 to the IDLE / INACTIVE UEs.

4. A user equipment (UE) configured to: receive a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquire modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.

5. The UE of claim 4, wherein the modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.

6. The UE of claim 5, configured to: store the updated UL WUS configuration of the NES Cell.

7. The UE of claim 4, wherein to re-acquire the modified OD-SIB 1, the UE is configured to: detect at least one condition comprising: cell selection, cell -re sei ection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; request OD-SIB 1 transmission at least based on the updated UL WUS configuration; and receive the modified OD-SIB 1 based on the requested OD-SIB 1 transmission.

8. A Network Energy Saving (NES) Cell configured to: broadcast an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmit a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode; receive, from at least one UE, a request for modified on-demand system information block 1 (OD-SIB 1) transmission based on the updated UL WUS configuration, while in ES mode; and initiate the modified OD-SIB 1 transmission at least based on the received request.

9. The NES Cell of claim 8, wherein the paging message indicates the at least one UE to re-acquire OD-SIB 1 and access the updated UL WUS configuration.

10. The NES Cell of claim 8, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

11. A user equipment (UE) configured to: receive a paging message with SystemlnfoModifi cation from Network Energy Saving (NES) Cell; receive an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB); in response to receipt of the paging message and the updated UL WUS configuration, detect at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and request on demand system information block 1 (OD-SIB1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

12. The UE of claim 11, wherein to request the SIB1, the UE is configured to: transmit a request for OD-SIB1 transmission to the NES Cell based on the UL WUS configuration of the NES Cell; and receive modified OD-SIB1 from the NES Cell based on the transmitted request.

13. The UE of claim 11, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

14. A method performed by a Network Energy Saving (NES) Cell, the method comprising: detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode; broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; andtransmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

15. The method of claim 14, wherein the paging message indicates the updated WUS configuration of the NES cell to the IDLE / INACTIVE UEs.

16. The method of claim 14, further comprising: transmitting modified OD-SIB1 to the IDLE / INACTIVE UEs.

17. A method performed by a user equipment (UE), the method comprising: receiving a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquiring modified OD-SIB1 and the updated UL WUS configuration at least based on the paging message.

18. The method of claim 17, wherein the modified OD-SIB1 includes the necessary information to access the updated UL WUS configuration of the NES Cell.

19. The method of claim 18, further comprising: storing the updated UL WUS configuration of the NES Cell.

20. The method of claim 17, wherein re-acquiring the modified OD-SIB1 comprising: detecting at least one condition comprising: cell selection, cell-resel ection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification,upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; requesting OD-SIB1 transmission at least based on the updated UL WUS configuration; and receiving the modified OD-SIB1 based on the requested OD-SIBl transmission.

21. A method performed by a Network Energy Saving (NES) Cell, the method comprising: broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non- energy saving (non-ES) mode to ES mode; receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIBl) transmission based on the updated UL WUS configuration, while in ES mode; and initiating the modified OD-SIBl transmission at least based on the received request.

22. The method of claim 21, wherein the paging message indicates the at least one UE to re-acquire OD-SIBl and access the updated UL WUS configuration.

23. The method of claim 21, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

24. A method performed by user equipment (UE), the method comprising: receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell; receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB);in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network from another radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and requesting on demand system information block 1 (OD-SIB 1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

25. The method of claim 24, wherein requesting the SIB 1, the UE is configured to: transmitting a request for OD-SIB 1 transmission to the NES Cell based on the UL WUS configuration of the NES Cell; and receiving modified OD-SIB 1 from the NES Cell based on the transmitted request.

26. The method of claim 24, wherein the SIB1 includes a value tag indicating whether SIB1 is modified or unchanged compared to previous version of SIB1 stored at the UE.

27. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: detecting an update in uplink (UL) wake-up signal (WUS) configuration of the NES Cell, when NES cell is in energy saving (ES) mode; broadcasting the updated UL WUS configuration in a corresponding system information block (SIB) of the NES cell; and transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell to inform about a modified on-demand SIB 1 (OD-SIB1) transmission, in response to detection of the update in UL WUS configuration of the NES Cell.

28. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: receiving a paging message with SystemlnfoModification from a Network Energy Saving (NES) Cell, wherein the paging message indicates an on demand system information block 1 (OD SIB1) transmission to acquire an updated uplink wake-up signal (UL WUS) configuration; and re-acquiring modified OD-SIBl and the updated UL WUS configuration at least based on the paging message.

29. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: broadcasting an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB), in response to detection of change in UL WUS configuration of the NES cell; transmitting a paging message with SystemlnfoModification to IDLE / INACTIVE user equipment (UEs) camped on the NES Cell before switching from the non-energy saving (non-ES) mode to ES mode; receiving, from at least one UE, a request for modified on-demand system information block 1 (OD-SIBl) transmission based on the updated UL WUS configuration, while in ES mode; and initiating the modified OD-SIBl transmission at least based on the received request.

30. A non-transitory computer-readable medium having computer-readable instructions that when executed by an apparatus causes the apparatus to perform operations of: receiving a paging message with SystemlnfoModification from Network Energy Saving (NES) Cell; receiving an updated uplink wake-up signal (UL WUS) configuration of the NES cell in a corresponding system information block (SIB); in response to receipt of the paging message and the updated UL WUS configuration, detecting at least one condition comprising: cell selection, cell-reselection, return from out of coverage, after reconfiguration with sync completion, after entering the network fromanother radio access technology (RAT), upon receiving an indication that system information (SI) is changed, upon receiving a Public Warning System (PWS) notification, upon receiving request from upper layers, the UE does not have a valid version of a stored SIB, or a valid version of a requested SIB; and requesting on demand system information block 1 (OD-SIB 1) transmission based on the updated UL WUS configuration, at least based on the detection of the at least one condition.

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