WO2025208609A1

WO2025208609A1 - On-demand system information block type 1 transmission

Info

Publication number: WO2025208609A1
Application number: PCT/CN2024/086228
Authority: WO
Inventors: Yushu Zhang; Ming-Hung Tao
Original assignee: Google LLC
Current assignee: Google LLC
Priority date: 2024-04-05
Filing date: 2024-04-05
Publication date: 2025-10-09
Anticipated expiration: 2026-10-05

Abstract

This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for an UL-WUS to request an on-demand SIB1. A UE (102) receives (730), from a first network entity (104a), a first configuration configuring an uplink-wakeup signal, UL-WUS for requesting system information block type 1, SIB1, associated with a second network entity (104b). The UE (102) transmits (740), to the first network entity (104a), the UL-WUS based on status information of the SIB1. The UE 102 receives (750), from the first network entity (104a), a response indicating a second configuration for monitoring the SIB1 from the second network entity (104b).

Description

ON-DEMAND SYSTEM INFORMATION BLOCK TYPE 1 TRANSMISSION

TECHNICAL FIELD

The present disclosure relates generally to wireless communication, and more particularly, a user equipment (UE) request to receive a system information block type 1 (SIB1) from a network entity.

BACKGROUND

The Third Generation Partnership Project (3GPP) specifies a radio interface referred to as fifth generation (5G) new radio (NR) (5G NR) . An architecture for a 5G NR wireless communication system includes a 5G core (5GC) network, a 5G radio access network (5G-RAN) , a user equipment (5G UE) , etc. The 5G NR architecture seeks to provide increased data rates, decreased latency, and/or increased capacity compared to prior generation cellular communication systems.

In a wireless communication system, a network entity and a user equipment (UE) may implement techniques to reduce power consumption. For example, a UE operates in a radio resource control (RRC) connected state when the UE has an active wireless connection with a network entity. During times when the UE does not have an active wireless connection with the network entity, the UE may enter into a power saving mode. For example, the UE transitions from the RRC connected state to an RRC idle state or RRC inactive state. In the RRC idle state, the UE releases the RRC configuration. In the RRC inactive state, the UE suspends the RRC configuration and the RRC configuration may remain dormant until the UE transitions back to the RRC connected state. During the RRC idle or inactive states, the UE may obtain downlink synchronization signals blocks (SSBs) and system information (SI) (e.g., system information block type 1 (SIB1) ) from the network entity. The UE relies on SIB1 from the network entity for various operations, such as initial cell access, cell-reselection, return from out of coverage, performing a random access procedure, and transitioning to RRC connected state, among other examples.

It is desirable to reduce signaling overhead and improve network energy performance. Some recent improvements to wireless communication technology are based on network energy saving (NES) in which the network entity eliminates or reduces some uplink and downlink transmissions. For example, the network entity (e.g., NES network entity) might refrain from transmitting some of the SIB1s associated with particular cells or beams operated by the network entity. In order to trigger the initial access procedure for the UE to access the NES network entity (e.g., NES cell) , the UE may need to transmit an uplink wake-up signal (UL-WUS) to request the SIB1 from the NES cell.

BRIEF SUMMARY

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects. This summary neither identifies key or critical elements of all aspects nor delineates the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In some aspects, the UE may transmit the UL-WUS signal (e.g., physical random access channel (PRACH) signal) to another network entity requesting the SIB1 (e.g., an on-demand SIB1) from the NES network entity based on status information of the on-demand SIB1. Accordingly, responsive to the request, the other network entity may transmit a signal (e.g., a network entity WUS) to the NES network entity requesting the NES network entity to transmit the on-demand SIB1 to the UE. The NES network entity may transmit the on-demand SIB1 to the UE. The UE may then perform an initial access procedure to access the NES network entity using the information from the SIB1. In some aspects, the UE may transmit the UL-WUS when the status information indicates that a previously received (e.g., prior) SIB1 is no longer valid (e.g., no longer effective) . For example, the prior SIB1 may be effective for an effective time period. The UE may transmit the UL-WUS after the effective time period. Additionally or alternatively, the UE may determine (or receive an indication from the first network entity) to transmit the UL-WUS when the status information indicates that one or more parameters included in the SIB1 have been updated or modified. For example, the UE may perform a comparison of a value tag associated with on-demand SIB1 and a value tag associated with the prior SIB1.

According to some aspects, a UE receives, from a first network entity, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The UE transmits, to the first network entity, the UL-WUS based on status information of the SIB1. The UE receives, from the first network entity, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

According to some aspects, a first network entity transmits, to a UE, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The first network entity receives, from the UE, the UL-WUS based on status information of the SIB1. The first network entity transmits, to the UE, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

According to some aspects, a second (NES) network entity transmits, to a UE, a first SIB1 associated with the second network entity (104b) . The second network entity receives, from a first network entity, a network entity wakeup signal. The second network entity transmits, to the UE in response to receiving the network entity wakeup signal, a second SIB1 associated with the second network entity, the second SIB1 being different from the first SIB1. The second network entity receives, from the UE, a PRACH signal for initial access based on the second SIB1.

Technical benefits of the present disclosure include reducing initial access latency, reducing network overhead, and reducing power consumption in a network entity and/or a UE.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a diagram of a wireless communications system that includes a plurality of user equipments (UEs) and network entities in communication over one or more cells according to an embodiment.

FIG. 2 illustrates a scheduling diagram for a network entity that transmits multiple SSBs and associated SIB1s according to an embodiment.

FIG. 3 illustrates network entities transmitting SIB1s to a UE based on SIB1 value tags according to an embodiment.

FIG. 4 illustrates network entities transmitting SIB1s to a UE based on an effective time for the SIB1 according to an embodiment.

FIG. 5 illustrates network entity initial access and on-demand SIB1 monitoring according to an embodiment.

FIG. 6 illustrates scheduling for a network entity that transmits multiple SSBs and associated SIB1s based on a slot offset according to an embodiment.

FIG. 7 is a signaling diagram illustrating on-demand SIB1 transmission according to an embodiment.

FIG. 8 is a signaling diagram illustrating on-demand SIB1 transmission and network entity initial access according to an embodiment.

FIG. 9 is a flowchart of a method of wireless communication at a UE according to an embodiment.

FIG. 10 is a flowchart of a method of wireless communication at a first network entity according to an embodiment.

FIG. 11 is a flowchart of a method of wireless communication at a second (NES) network entity according to an embodiment.

FIG. 12 is a diagram illustrating a hardware implementation for an example UE apparatus according to some embodiments.

FIG. 13 is a diagram illustrating a hardware implementation for one or more example network entities according to some embodiments.

In FIGs. 1-13 like reference numbers refer to like features.

DETAILED DESCRIPTION

FIG. 1 illustrates a diagram 100 of a wireless communications system associated with a plurality of cells 190. The wireless communications system includes user equipments (UEs) 102 and base stations/network entities 104. Some base stations may include an aggregated base station architecture and other base stations may include a disaggregated base station architecture. The aggregated base station architecture utilizes a radio protocol stack that is physically or logically integrated within a single radio access network (RAN) node. A disaggregated base station architecture utilizes a protocol stack that is physically or logically distributed among two or more units (e.g., radio unit (RU) 106, distributed unit (DU) 108, central unit (CU) 110) . For example, a CU 110 is implemented within a RAN node, and one or more DUs 108 may be co-located with the CU 110, or alternatively, may be geographically or virtually distributed throughout one or multiple other RAN nodes. The DUs 108 may be implemented to communicate with one or more RUs 106. Any of the RU 106, the DU 108 and the CU 110 can be implemented as virtual units, such as a virtual radio unit (VRU) , a virtual distributed unit (VDU) , or a virtual central unit (VCU) . The base station/network entity 104 (e.g., an aggregated base station or disaggregated units of the base station, such as the RU 106 or the DU 108) , may be referred to as a transmission reception point (TRP) .

Operations of the base station 104 and/or network designs may be based on aggregation characteristics of base station functionality. For example, disaggregated base station architectures are utilized in an integrated access backhaul (IAB) network, an open-radio access network (O-RAN) network, or a virtualized radio access network (vRAN) , which may also be referred to a cloud radio access network (C-RAN) . Disaggregation may include distributing functionality across the two or more units at various physical locations, as well as distributing functionality for at least one unit virtually, which can enable flexibility in network designs. The various units of the disaggregated base station architecture, or the disaggregated RAN architecture, can be configured for wired or wireless communication with at least one other unit. For example, the base stations 104d, 104e and/or the RUs 106a, 106b, 106c, 106d may communicate with the UEs 102a, 102b, 102c, 102d, and/or 102s via one or more radio frequency (RF) access links based on a Uu interface. In examples, multiple RUs 106 and/or base stations 104 may simultaneously serve the UEs 102, such as by intra-cell and/or inter-cell access links between the UEs 102 and the RUs 106/base stations 104.

The RU 106, the DU 108, and the CU 110 may include (or may be coupled to) one or more interfaces configured to transmit or receive information/signals via a wired or wireless transmission medium. For example, a wired interface can be configured to transmit or receive the information/signals over a wired transmission medium, such as via the fronthaul link 160 between the RU 106d and the baseband unit (BBU) 112 of the base station 104d associated with the cell 190d. The BBU 112 includes a DU 108 and a CU 110, which may also have a wired interface (e.g., midhaul link) configured between the DU 108 and the CU 110 to transmit or receive the information/signals between the DU 108 and the CU 110. In further examples, a wireless interface, which may include a receiver, a transmitter, or a transceiver, such as an RF transceiver, configured to transmit and/or receive the information/signals via the wireless transmission medium, such as for information communicated between the RU 106a of the cell 190a and the base station 104e of the cell 190e via cross-cell communication beams 136-138 of the RU 106a and the base station 104e.

The RUs 106 may be configured to implement lower layer functionality. For example, the RU 106 is controlled by the DU 108 and may correspond to a logical node that hosts RF processing functions, or lower layer PHY functionality, such as execution of fast Fourier transform (FFT) , inverse FFT (iFFT) , digital beamforming, physical random access channel (PRACH) extraction and filtering, etc. The functionality of the RU 106 may be based on the functional split, such as a functional split of lower layers.

The RUs 106 may transmit or receive over-the-air (OTA) communication with one or more UEs 102. For example, the RU 106b of the cell 190b communicates with the UE 102b of the cell 190b via a first set of communication beams 132 of the RU 106b and a second set of communication beams 134b of the UE 102b, which may correspond to inter-cell communication beams or, in some examples, cross-cell communication beams. For instance, the UE 102b of the cell 190b may communicate with the RU 106a of the cell 190a via a third set of communication beams 134a of the UE 102b and a fourth set of communication beams 136 of the RU 106a. DUs 108 can control both real-time and non-real-time features of control plane and user plane communications of the RUs 106.

Any combination of the RU 106, the DU 108, and the CU 110, or reference thereto individually, may correspond to a base station 104. Thus, the base station 104 may include at least one of the RU 106, the DU 108, or the CU 110. The base stations 104 provide the UEs 102 with access to a core network. The base stations 104 may relay communications between the UEs 102 and the core network (not shown) . The base stations 104 may be associated with macrocells for higher-power cellular base stations and/or small cells for lower-power cellular base stations. For example, the cell 190e may correspond to a macrocell, whereas the cells 190a-190d may correspond to small cells. Small cells include femtocells, picocells, microcells, etc. A network that includes at least one macrocell and at least one small cell may be referred to as a “heterogeneous network. ”

Transmissions from a UE 102 to a base station 104/RU 106 are referred to as uplink (UL) transmissions, whereas transmissions from the base station 104/RU 106 to the UE 102 are referred to as downlink (DL) transmissions. Uplink transmissions may also be referred to as reverse link transmissions and downlink transmissions may also be referred to as forward link transmissions. For example, the RU 106d utilizes antennas of the base station 104d of cell 190d to transmit a downlink/forward link communication to the UE 102d or receive an uplink/reverse link communication from the UE 102d based on the Uu interface associated with the access link between the UE 102d and the base station 104d/RU 106d.

Communication links between the UEs 102 and the base stations 104/RUs 106 may be based on multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be associated with one or more carriers. The UEs 102 and the base stations 104/RUs 106 may utilize a spectrum bandwidth of Y MHz (e.g., 5, 10, 15, 20, 100, 400, 800, 1600, 2000, etc. MHz) per carrier allocated in a carrier aggregation of up to a total of Yx MHz, where x component carriers (CCs) are used for communication in each of the uplink and downlink directions. The carriers may or may not be adjacent to each other along a frequency spectrum. In examples, uplink and downlink carriers may be allocated in an asymmetric manner, with more or fewer carriers allocated to either the uplink or the downlink. A primary component carrier and one or more secondary component carriers may be included in the component carriers. The primary component carrier may be associated with a primary cell (PCell) and a secondary component carrier may be associated with a secondary cell (SCell) .

Some UEs 102, such as the UEs 102a and 102s, may perform device-to-device (D2D) communications over sidelink. For example, a sidelink communication/D2D link utilizes a spectrum for a wireless wide area network (WWAN) associated with uplink and downlink communications. Such sidelink/D2D communication may be performed through various wireless communications systems, such as wireless fidelity (Wi-Fi) systems, Bluetooth systems, Long Term Evolution (LTE) systems, New Radio (NR) systems, etc.

The UEs 102 and the base stations 104/RUs 106 may each include a plurality of antennas. The plurality of antennas may correspond to antenna elements, antenna panels, and/or antenna arrays that may facilitate beamforming operations. For example, the RU 106b transmits a downlink beamformed signal based on a first set of communication beams 132 to the UE 102b in one or more transmit directions of the RU 106b. The UE 102b may receive the downlink beamformed signal based on a second set of communication beams 134b from the RU 106b in one or more receive directions of the UE 102b. In a further example, the UE 102b may also transmit an uplink beamformed signal (e.g., sounding reference signal (SRS) ) to the RU 106b based on the second set of communication beams 134b in one or more transmit directions of the UE 102b. The RU 106b may receive the uplink beamformed signal from the UE 102b in one or more receive directions of the RU 106b. The UE 102b may perform beam training to determine the best receive and transmit directions for the beamformed signals. The transmit and receive directions for the UEs 102 and the base stations 104/RUs 106 may or may not be the same.

In further examples, beamformed signals may be communicated between a first base station/RU 106a and a second base station 104e. For instance, the base station 104e of the cell 190e may transmit a beamformed signal to the RU 106a based on the communication beams 138 in one or more transmit directions of the base station 104e. The RU 106a may receive the beamformed signal from the base station 104e of the cell 190e based on the RU communication beams 136 in one or more receive directions of the RU 106a. In further examples, the base station 104e transmits a downlink beamformed signal to the UE 102e based on the communication beams 138 in one or more transmit directions of the base station 104e. The UE 102e receives the downlink beamformed signal from the base station 104e based on UE communication beams 130 in one or more receive directions of the UE 102e. The UE 102e may also transmit an uplink beamformed signal to the base station 104e based on the UE communication beams 130 in one or more transmit directions of the UE 102e, such that the base station 104e may receive the uplink beamformed signal from the UE 102e in one or more receive directions of the base station 104e.

The base station 104 may include and/or be referred to as a network entity. That is, “network entity” may refer to the base station 104 or at least one unit of the base station 104, such as the RU 106, the DU 108, and/or the CU 110. The base station 104 may also include and/or be referred to as a next generation evolved Node B (ng-eNB) , a next generation NB (gNB) , an evolved NB (eNB) , an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS) , an extended service set (ESS) , a TRP, a network node, network equipment, or other related terminology. The base station 104 or an entity at the base station 104 can be implemented as an IAB node, a relay node, a sidelink node, an aggregated (monolithic) base station, or a disaggregated base station including one or more RUs 106, DUs 108, and/or CUs 110. A set of aggregated or disaggregated base stations may be referred to as a next generation-radio access network (NG-RAN) . In some examples, the UE 102a operates in dual connectivity (DC) with the base station 104e and the base station/RU 106a. In such cases, the base station 104e can be a master node and the base station/RU 160a can be a secondary node.

Still referring to FIG. 1, in certain aspects, any of the UEs 102 may include an on-demand SIB1 component 140 configured to receive, from a first network entity, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The on-demand SIB1 component 140 is further configured to transmit, to the first network entity, the UL-WUS based on status information of the SIB1. The on-demand SIB1 component 140 is further configured to receive, from the first network entity, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

In certain aspects, any of the base stations 104 or a network entity of the base stations 104 may include an on-demand SIB1 configuration component 150 configured to transmit, to a UE, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The on-demand SIB1 configuration component 150 is further configured to receive, from the UE, the UL-WUS based on status information of the SIB1. The on-demand SIB1 configuration component 150 is further configured to transmit, to the UE, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

In certain aspects, any of the base stations 104 or a network entity of the base stations 104 may include an on-demand SIB1 configuration component 150 configured to transmit, to a UE, a first SIB1 associated with the second network entity. The on-demand SIB1 configuration component 150 is further configured to receive, from a first network entity, a network entity wakeup signal. The on-demand SIB1 configuration component 150 is further configured to transmit, to the UE in response to receiving the network entity wakeup signal, a second SIB1 associated with the second network entity, the second SIB1 being different from the first SIB1. The on-demand SIB1 configuration component 150 is further configured to receive, from the UE, a PRACH signal for initial access based on the second SIB1.

Accordingly, FIG. 1 describes a wireless communication system that may be implemented in connection with aspects of one or more other figures described herein. Further, although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as 5G-Advanced and future versions, LTE, LTE-advanced (LTE-A) , and other wireless technologies, such as 6G.

FIG. 2 illustrates a scheduling diagram 200 for a network entity that transmits multiple SSBs 230 and associated SIB1s according to an embodiment. In the example shown in FIG. 2, there are multiple monitoring occasions (MOs) for a UE to monitor a search space (SS) (e.g., SS in control resource set (CORESET) 0) . A network entity may broadcast multiple SSBs (e.g., SSB1 230a and/or SSB2 230b) . For example, a first MO occurs at slot 6 where a PDCCH 232a schedules PDSCH 233a carrying a SIB1 associated with the SSB1 230a. A second MO occurs at slot 7, where a PDCCH 232b schedules PDSCH 233b carrying a SIB1 associated with the SSB1 230b.

In some aspects, the SSB 230 includes downlink synchronization signals (e.g., a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) ) for the UE to maintain synchronization with the network entity. Each SSB 230 may include a master information block (MIB) and other information to enable the UE to receive the SIB1 via the PDSCH 233. While each cell has at least one SSB 230, the network entity may transmit multiple SSBs 230 within a cell. For example, the network entity may transmit a different SSB 230 for each of a plurality of beams or transmission/reception points (TRPs) . Additionally or alternatively, a network entity may operate multiple cells and transmit multiple SSBs 230 for the cells. To conserve bandwidth and energy, the network entity may refrain from transmitting the SIB1 (s) for some or all of the SSBs 230 that the network entity transmits. For example, the network entity may transmit SSB 1 230a in slot 1 and refrain from transmitting the SIB1 (e.g., via PDSCH 233a) in associated slot 6. As another example, the network entity may transmit SSB 2 230b in slot 2 and refrain from transmitting the SIB1 (e.g., via PDSCH 233b) in associated slot 7.

Due to a limited payload size in the physical broadcast channel (PBCH) carrying the MIB, the network entity can only transmit part of the common configuration in the MIB. The network entity may transmit the remaining common configuration in a SIB1 via the PDSCH 233. The SIB1 is part of a minimum SI needed by the UE to perform certain functions such as a random access procedure or cell selection/cell reselection. The MIB may include a field (e.g., PDCCH-ConfigSIB1) indicating the PDCCH 232 as a monitoring occasion for the UE to obtain downlink control information. The PDCCH 232 includes scheduling of the PDSCH 233 which includes the SIB1. The network entity transmits the PDSCH 233 based on a system information radio network temporary identifier (SI-RNTI) , which is pre-defined as ‘0xFFFF’ . The network entity schedules the SIB1 by the PDCCH 232 in search space (SS) 0 on CORESET 0. The network entity configures the time and frequency location for the monitoring occasion SS/CORESET 0 associated with the SSB by the MIB transmitted via the SSB 230 (e.g., PDCCH-ConfigSIB1) . The network entity may transmit the SSB 1 230a and the PDCCH 232a/PDSCH 233a for the SIB1 associated with the SSB 1 230a based on the same beam settings. The network entity may transmit the SSB 2 230b and the PDCCH 232b/PDSCH 233b for the SIB1 associated with the SSB 2 230b based on the same beam settings. The beam settings for SSB 1 230a and SSB 2 230b may be different. Thus, the UE may determine the demodulation reference signal (DMRS) of the PDCCH 232/PDSCH 233 for the SIB1 is quasi-co-located (QCLed) with the associated SSB 230 based on one or more parameters, such as delay spread, average delay, Doppler shift, Doppler spread, spatial reception parameter, and/or antenna gain.

FIG. 3 illustrates diagrams 300, 301, and 302 of network entities 104 transmitting SIB1s 308 to a UE 102 based on status information (e.g., SIB1 value tags) according to an embodiment. In some aspects, the network entity 104 may transmit SIB1 periodically. In some aspects, the network entity 104b may enter a NES mode and may not transmit the SIB1 for some SSBs.

In some aspects, the UE 102 may have received an SIB1 from the network entity 104b before the network entity 104b entered the NES mode. The UE 102 may be in RRC idle mode or RRC inactive mode. For RRC idle mode, the UE 102 may release the RRC configurations. For RRC inactive mode, the UE 102 may suspend the RRC configurations and store the RRC configurations in the UE inactive access stratum (AS) context. However, after the UE 102 attempts to camp again on the network entity 104b (e.g., when the UE 102 reselects the network entity 104b from another network entity/cell and/or the UE 102 recovers from an out-of-coverage situation) , the UE 102 may have no information on whether the SIB1 for the network entity 104b has changed or not. If the UE 102 has no information on whether SIB1 has changed or not, the UE 102 may request the on-demand SIB1 from the network entity 104b. However, if the SIB1 has not changed, the UE 102 will be unnecessarily requesting the on-demand SIB1 thereby wasting energy and resources in the UE 102 and the network entity 104b. Aspects of the present disclosure may include the UE 102 transmitting an UL-WUS to request an on-demand SIB1 based on status information (e.g., whether the SIB1 for the network entity 104b has changed or not) .

Referring to FIG. 3, diagram 300 illustrates the network entity 104b (e.g., a second network entity) transmitting, to the UE 102, a SIB1 308a and optionally status information (e.g., a value tag) associated with the first SIB1 308a. The value tag may be a hash function or other suitable function of the SIB1 308a. The network entity 104b may configure the UE 102 with the value tag for SIB1 308a by transmitting, to the UE 102, an indicator of the value tag via the SIB1 308a, a master information block (MIB) , another SIB, and/or a PDCCH scheduling a PDSCH carrying the SIB1 208a. Additionally or alternatively, the UE 102 may determine (e.g., compute or calculate) the value tag for the SIB1 308a. For example, the UE 102 may receive the SIB1 308a and determine its value tag by taking the entire or partial SIB1 308a message as an input to a hash function, where the output of the hash function (e.g., the value tag) may be a k-bit integer X. In some aspects, the network entity 104a (e.g., a first network entity not in NES mode) and/or the network entity 104b may determine the value tag for the on-demand SIB1 308b associated with the network entity 104b by feeding the on-demand SIB1 308b into the same hash function employed by the UE 102. The network entity 104a may include the value tag 307 for the on-demand SIB1 in a SIB1, in another SIB, and/or in the UL-WUS configuration 330. In some other implementations, the status information of a SIB1 includes not only the value tag but also a System Information Area Identity (i.e., systemInformationAreaID) . In such implementations, when two different SIB1s (of the same cell or different cells) have the same value tag value but have different systemInformationAreaIDs, these two SIB1s shall not be considered as identical. In other words, two different SIB1s are considered as identical only if both their systemInformationAreaIDs and value tags are identical.

In some aspects, the network entity 104a may receive the on-demand value tag 307 from the network entity 104b over link 311 (e.g., an X2 interface, shared memory, or other suitable link) . Although the first network entity 104a and second network entity 104a are described as different network entities, they may be the same network entity 104 operating different cells. In some aspects, the first network entity 104a is different from the second network entity 104b. For ease of description, this disclosure refers to the first network entity 104a as operating a first cell and the second network entity 104b as operating a second cell. The first network entity 104a and the second network entity 104b can coordinate with each other via link 311.

The UE 102 may determine that the value tag 307 for the on-demand SIB1 308b is different from or the same as the value tag for the SIB1 308a. For example, the UE 102 may receive the value tag 307 for the on-demand SIB1 308b from the first network entity 104a and compare the value tag 307 to the value tag for the SIB1 308a. Additionally or alternatively, the network entity 104a may transmit an indicator to the UE 102 indicating whether the value tag 307 for the on-demand SIB1 308b is different from the value tag for the SIB1 308a.

As shown in diagram 301, if the UE 102 determines that the value tag associated with the SIB1 308a (e.g., stored in the UE 102) is different from the value tag 307 for the on-demand SIB1 308b, the UE 102 may transmit, to the first network entity 104a, an UL-WUS 340a to request the on-demand SIB1 308b. The network entity 104a may transmit (e.g., forward) , to the second network entity 104b over the link 311, a network entity WUS and the request for the on-demand SIB1 308b. Additionally or alternatively , the UE 102 may transmit, to the second network entity 104b, the UL-WUS 340b to request the on-demand SIB1 308b. In response to the request, the network entity 104b may transmit, to the UE 102, the on-demand SIB1 308b. The UE 102 may then perform an initial access procedure to access the network entity 104b based on the on-demand SIB1 308b.

As shown in diagram 302, if the UE 102 determines that the value tag associated with the SIB1 308a is the same as the value tag 307 for the on-demand SIB1 308b, the UE 102 may consider the previously received SIB1 308a (e.g., the stored SIB1) as a valid (e.g., effective) SIB1 for the network entity 104b and the UE 102 may refrain from transmitting the UL-WUS to the network entity 104a and perform an initial access procedure 309 to access the network entity 104b based on the stored SIB1 308a. In some other implementations, (not shown in FIG. 3) , if the UE 102 determines that the value tag and the systemInformationAreaID of the SIB1 308a transmitted by the network entity 104b are identical to the value tag and the systemInformationAreaID of the on-demand SIB1 308b, the UE 102 may consider the SIB1 transmitted by the network entity 104b to be identical to the on-demand SIB1 308b and the UE 102 may refrain from transmitting the UL-WUS to the network entity 104a.

FIG. 4 illustrates a diagram 400 of network entities 104 transmitting SIB1s to a UE 102 based on status information (e.g., an effective time 404) for the SIB1 according to an embodiment. The effective time 404 may be a time period for which the SIB1 is valid. In some aspects, the network entity 104b may operate in a NES mode and configure the effective time 404 for a periodically transmitted SIB1. The network entity 104b may transmit, to the UE 102, the SIB1 effective time 404b configuration via the SIB1, another SIB, a MIB, and/or the PDCCH scheduling a PDSCH for the SIB1. Additionally or alternatively, the network entity 104b may transmit, to the network entity 104a via the link 311, the SIB1 effective time 404. The network entity 104a may in turn transmit, to the UE 102, the SIB1 effective time 404a configuration to the UE 102 via another SIB1, another SIB, another MIB, and/or the PDCCH scheduling a PDSCH for the SIB1.

In some aspects, the UE 102 may start or reset a timer based on the effective time 404 when the UE 102 receives the SIB1 from the network entity 104b. While the timer is running, the UE 102 may refrain from transmitting the UL-WUS 340a indicating an on-demand SIB1 request since the SIB1 remains unchanged during the effective time. In some aspects, when the timer is expired the UE 102 may transmit, to the network entity 104a, the UL-WUS 340a to request the on-demand SIB1 from the network entity 104b. In some other aspects, the UE 102 may transmit, to the second network entity 104b, the UL-WUS 340b to request the on-demand SIB1 from the network entity 104b. The network entity 104a may transmit (e.g., forward) , to the second network entity 104b over the link 311, a network entity WUS and the request for the on-demand SIB1. In response to the request, the network entity 104b may transmit, to the UE 102, the on-demand SIB1. The UE 102 may then perform an initial access procedure to access the network entity 104b based on the on-demand SIB1.

FIG. 5 illustrates a diagram 500 of network entity 104 initial access and on-demand SIB1 monitoring according to an embodiment. In some aspects, the UE 102 may determine whether to transmit, to the network entity 104a, the UL-WUS 340a to request an on-demand SIB1 308 from the network entity 104b or whether to perform an initial access procedure to access network entity 104a (e.g., fallback to perform initial access) . In some other aspects, the UE 102 may determine whether to transmit, to the second network entity 104b, the UL-WUS 340b to request the on-demand SIB1 from the network entity 104b or whether to perform an initial access procedure to access network entity 104a. The UE 102 may determine whether to transmit the UL-WUS based on status information of the on-demand SIB1 308 (e.g., a value tag comparison as described with reference to FIG. 3 and/or a SIB1 effective time as described with reference to FIG. 4) .

In some aspects, the UE 102 may determine whether to fallback to perform initial access to the network entity 104a based on measurement information (e.g., first measurement information associated with the first network entity 104a and/or second measurement information associated with the second network entity 104b) . The measurement information may include a measured reference signal received power (RSRP) (e.g., layer 1 RSRP (L1-RSRP) and/or layer 3 RSRP (L3-RSRP) ) associated with the network entity 104a and/or the network entity 104b, a measured signal to interference plus noise ratio (SINR) (e.g., L1-SINR and/or L3-SINR) for the network entity 104a and/or the network entity 104b, and/or a measured reference signal received quality (RSRQ) for the network entity 104a and/or the network entity 104b. The UE 102 may measure the RSRP/SINR/RSRQ for the network entity 104a and/or the network entity 104b based on one or more SSBs.

In some aspects, the UE 102 may determine to fallback to perform initial access to the network entity 104a based on at least one of the following conditions:

-The RSRP associated with the first network entity 104a is greater than the RSRP associated with the second network entity 104b minus a first offset;

-The SINR associated with the first network entity 104a is greater than the SINR associated with the second network entity 104b minus a second offset;

-The RSRQ associated with the first network entity 104a is greater than the RSRQ associated with the second network entity 104b minus a third offset;

-The RSRP associated with the first network entity 104a is greater than a first threshold;

-The SINR associated with the first network entity 104a is greater than a second threshold;

-The RSRQ associated with the first network entity 104a is greater than a third threshold;

-The RSRP associated with the second network entity 104b is less than a fourth threshold;

-The SINR associated with the second network entity 104b is less than a fifth threshold; or

-The RSRQ associated with the second network entity 104b is less than a sixth threshold.

In some aspects, the first/second/third offsets and/or the first/second/third/fourth/fifth/sixth thresholds may be predefined or configured by the network entity 104a and/or the network entity 104b (e.g., by SIB1 or another SIB from the network entity 104a and/or the network entity 104b) . The measurement information (e.g., RSRP/SINR/RSRQ) to determine the fallback operation may be pre-defined or configured by the network entity 104a and/or the network entity 104b.

The UE 102 may trigger the on-demand SIB1 procedure, (e.g., transmitting the UL-WUS 340 to request the on-demand SIB1 308 from the network entity 104b) if the UE 102 determines not to fallback to access the network entity 104a. The network entity 104a may transmit (e.g., forward) , to the second network entity 104b over the link 311, a network entity WUS 503 and the request for the on-demand SIB1. Otherwise, if the UE 102 determines to fallback to access the network entity 104a, the UE 102 may perform the initial access procedure to access the network entity 104a based on the configuration 530 (e.g., a second configuration) received from the network entity 104a.

In some aspects, the UL-WUS 340 may be a PRACH signal (e.g., a random access (RA) preamble) . The network entity 104a may configure dedicated PRACH resources for the UE 102 to transmit the UL-WUS 340. In some aspects, the network entity 104a may be connected to multiple network entities 104 operating in NES mode including the network entity 104b. The network entity 104a may configure multiple sets of dedicated PRACH resources, each of the dedicated sets of PRACH resources may be associated with a different network entity 104. For example, the network entity 104a may configure different PRACH resources corresponding to a different carrier frequency for the network entity 104b and/or different SSBs QCLed with the on-demand SIB1. In some aspects, the UE 102 may determine the PRACH resources for UL-WUS 340 based on the physical cell identifier (PCI) for the network entity 104b, the requested SSB index (es) QCLed with the PDSCH for the on-demand SIB1 and/or the carrier frequency for the on-demand SIB1. After receiving the UL-WUS 340 requesting the on-demand SIB1 for the network entity 104b, the network entity 104a may determine, based on the status information, whether the UE 102 should fallback to perform initial access to the network entity 104a or start to monitor resources for the on-demand SIB1 from the network entity 104b.

In response to receiving the UL-WUS 340 from the UE 102, the network entity 104a may transmit, to the UE 102, a response indicating configuration (e.g., a second configuration) for monitoring the SIB1 from the second network entity 104b or to configure the UE 102 for initial access the network entity 104a. The response may be a random access response (RAR) . The RAR may include a first RAR type to configure the UE 102 to monitor the on-demand SIB1 from the network entity 104b or a second RAR type (e.g., defined in 3GPP TS 38.321) to configure the UE 102 for initial access the network entity 104a. The second type of RAR may provide a configuration for the UE 102 to monitor for the on-demand SIB1 from the network entity 104b.

The network entity 104a may configure the RAR types by the corresponding medium access control (MAC) sub-header for the RAR. In one example, the network entity 104a may configure a backoff indicator (BI) in the MAC sub-header to indicate whether the first type of RAR or the second type of RAR is being transmitted by the network entity 104a. In another embodiment, the network entity 104a may provide a random access preamble identifier (RAPID) in the MAC sub-header corresponding to one of the random access preambles configured for the on-demand SIB1 request. The MAC payload for the RAR may be appended after the MAC sub-header to indicate whether the first type of RAR or the second type of RAR is transmitted.

As an alternative to the network entity 104a configuring dedicated PRACH resources for the UE 102 to transmit the UL-WUS 340, the network entity 104a may configure non-dedicated PRACH resources for the UE 102 to transmit the UL-WUS 340. For example, the PRACH resources may be shared by multiple network entities 104 operating in NES mode. In some aspects, the non-dedicated resources may be used for different functionalities (e.g., UL-WUS or PRACH for initial access) . After receiving the UL-WUS 340 (e.g., PRACH) from the UE 102, the network entity 104a may transmit a RAR scheduling a PUSCH for message 3 (Msg3) transmission. The UE 102 may transmit, to the network entity 104a, the scheduled PUSCH carrying the Msg3. In some aspects, the Msg3 may indicate the PCI associated with the network entity 104b, one or more SSBs (e.g., SSB indexes associated with the network entity 104b) that are QCLed with a PDSCH carrying the on-demand SIB1, the measurement information associated with the network entity 104a, the measurement information associated with the network entity 104b (e.g., to allow the network entity 104a to determine whether to fallback) , a carrier frequency associated with the on-demand SIB1, and/or a time window for the UE 102 to monitor the on-demand SIB1. The time window for the UE 102 to monitor the on-demand SIB1 may indicate the UE 102 preferred or recommended time window for the on-demand SIB1 reception (e.g., the minimum/maximum/preferred starting time and/or the minimum/maximum/preferred duration for the on-demand SIB1 monitoring) . The recommended time window may be indicated as a slot offset and/or frame offset.

In response to the Msg3, the network entity 104a may transmit, to the UE 102, a Msg4. The network entity 104a may transmit the Msg4 in a MAC-CE via PDSCH or in a DCI via PDCCH. The Msg4 may indicate to the UE 102 whether to fallback to performing an initial access procedure with the network entity 104a or whether to start to monitor the on-demand SIB1 from the network entity 104b. The Msg4 may include information (e.g., time/frequency resources) for the UE 102 to monitor the on-demand SIB1.

In some aspects, the UE 102 may transmit the UL-WUS 340 (e.g., PRACH signal) and the Msg3 in two separate transmissions (e.g., 4-step random access procedure) . Alternatively, the UE 102 may transmit the UL-WUS 340 (e.g., PRACH signal) and the Msg3 together in a single transmission (e.g., MsgA of 2-step random access procedure) .

In some aspects, the network entity 104a may transmit the RAR and the Msg4 in two separate transmissions (e.g., 4-step random access procedure) . Alternatively, the network entity 104a may transmit the RAR and the Msg4 together in a single transmission (e.g., MsgB of 2-step random access procedure) .

In some aspects, the UE 102 may use the dedicated PRACH resources to transmit the UL-WUS 340 corresponding to the on-demand SIB1 for the network entity 104b. Otherwise, the UE 102 may fallback to use other PRACH resources (e.g., common PRACH resources) to trigger the on-demand SIB1 procedure if the on-demand SIB1 for the network entity 104b is configured.

In response to receiving the UL-WUS 340, the network entity 104a may transmit, to the UE 102 via RAR, Msg4, and/or MsgB, at least one of following:

-An acknowledgement of receiving the UL-WUS 340. The UL-WUS 340 acknowledgement may include a random access preamble identifier (RAPID) indicating the PRACH preamble index transmitted by the UE 102;

-A backoff indicator (BI) indicating whether the UE 102 should fallback to perform an initial access procedure to access the network entity 104a;

-PCI information associated with the network entity 104b. The PCI information may serve as an acknowledgement from the network entity 104a that the UE 102 is requesting an on-demand SIB1 from the network entity 104b;

-The carrier frequency for the on-demand SIB1 requested from the network entity 104b;

-One or more SSB indexes that are QCLed with the PDCCH and/or the PDSCH for the on-demand SIB1.

-A value tag for the on-demand SIB1 (e.g., a hash function of the on-demand SIB1) ;

-Timing information for the UE 102 to start monitoring the on-demand SIB1. The timing information may indicate a subframe and/or radio frame for the UE 102 to start monitoring the on-demand SIB1;

-Timing information for the UE 102 to stop monitoring the on-demand SIB1. The timing information may indicate a subframe and/or radio frame for the UE 102 to stop monitoring the on-demand SIB1;

-A duration of a time window for the UE 102 to monitor the on-demand SIB1. The duration of the time window may be indicated as a number of symbols, slots, subframes, and/or radio frames;

-A configuration for retransmission of the UL-WUS. In some aspects, the UE 102 may transmit the UL-WUS 340 to request the on-demand SIB1 but the UE 102 may fail to receive the on-demand SIB1. If the UE 102 fails to receive the on-demand SIB1, the UE 102 may retransmit the UL-WUS 340 based on the UL-WUS 340 retransmission configuration which may include at least one of the following:

-A duration of a prohibit timer for retransmission of UL-WUS 340. In order to prevent a frequent or premature retransmission of the UL-WUS 340, the network entity 104a may configure a UL-WUS 340 retransmission prohibit timer during which the UE 102 will refrain from retransmitting the UL-WUS 340;

-A power ramping step size for the retransmission of the UL-WUS 340. The UE 102 may increase the power level of each retransmission of the UL-WUS 340 by the power ramping step size.

-An indicator of whether retransmission of the UL-WUS 340 is allowed or not.

In some aspects, the network entity 104a transmits a response to the UL-WUS 340, (e.g., via RAR, MSG4 and/or MSGB) , may include a downlink assignment for directly scheduling the PDSCH for the on-demand SIB1. Having the response include the downlink assignment scheduling the PDSCH may allow the UE 102 to refrain from monitoring and decoding a scheduling PDCCH that includes the downlink assignment, thereby reducing power consumption in the UE 102. The UE 102 monitors the PDSCH for the on-demand SIB1 based on the received downlink assignment. In some aspects, the downlink assignment may include one or more of the following information:

-A frequency domain resource assignment (FDRA) for the PDSCH;

-A time domain resource assignment (TDRA) for the PDSCH;

-A virtual resource block (VRB) to physical resource block (PRB) mapping. In some aspects, the VRB to PRB mapping may be used for frequency domain hopping and/or frequency inter-leaving;

-A modulation and coding scheme (MCS) for the PDSCH;

-A redundancy version (RV) for the PDSCH;

-A periodicity and/or slot offset for a reference slot for the PDSCH for the on-demand SIB1; or

-A number of repetitions for the PDSCH. In some aspects, the network entity 104a may repeat the transmission of the PDSCH to increase the probability of the UE 102 correctly decoding the PDSCH.

FIG. 6 illustrates a diagram 600 for scheduling a network entity that transmits multiple SSBs and associated SIB1s based on a slot offset according to an embodiment.

In some aspects, the UL-WUS response from the network entity 104a may not include the downlink assignment for the PDSCH 633 carrying the on-demand SIB1. If the UE 102 does not receive the downlink assignment directly scheduling the PDSCH 633 carrying the on-demand SIB1, then the UE 102 monitors a PDCCH scheduling the PDSCH 633 for the on-demand SIB1 in a search space (SS) (e.g., SS 0) corresponding to the SSB 630 QCLed with the PDCCH/PDSCH 633. The UE 102 then monitors the PDSCH 633 scheduled by the PDCCH for the on-demand SIB1.

In some aspects, downlink assignment may indicate a slot offset from the PDCCH to the PDSCH 633. However, since the downlink assignment directly schedules the PDSCH 633 without a PDCCH, the network entity 104a and UE 102 may determine a reference slot (e.g., a virtual PDCCH reference slot) for the slot offset for the PDSCH 633.

In the example of FIG. 6, the network entity 104a may configure a reference slot offset x in the downlink assignment in the response to the UL-WUS, and the slot offset based on the reference slot offset y set by the TDRA in the downlink assignment in response to the UL-WUS, then the network entity 104b transmits the PDSCH 633 for on-demand SIB1 in the slot n+x+y, where the network entity 104b transmits the SSB 630 in slot n. The SSB 630 is QCLed with the PDSCH 633. The network entity 104a may configure common or separate value of x and/or y for PDSCH 633 for on-demand SIB1 QCLed with different SSBs 630. For example, in FIG. 6, PDSCH 633a may use slot 5 as the reference slot and PDSCH 633b may use slot 6 as the reference slot. The reference slot may be indicated in the downlink assignment as an offset x from the SSB 630. In FIG. 6, x is a 4 slot offset from the SSB 630 in slot n. If the TDRA indicates an offset of y (e.g., 1 slot) then PDSCH 633a is scheduled for slot 1+4+1 =slot 6. Similarly, PDSCH 633b is scheduled for slot 2+4+1 = slot 7.

In some aspects, the network entity 104b may transmit the PDSCH 633 for on-demand SIB1 by one or more repetitions. The network entity 104b may transmit different repetitions in different slots and/or in different symbols. The network entity 104b may further configure the repetition types (e.g., slot level and/or symbol level) . The network entity 104b may transmit different repetitions of the PDSCH 633 by the same or different redundancy version (RV) . The RV for each repetition may be pre-defined or configured by the network entity 104b.

In some aspects, the network entity 104b may transmit the PDSCH 633 for the on-demand SIB1 based on one antenna port and the configured downlink assignment. The network entity 104b may transmit the PDSCH 633 for the on-demand SIB1 based on a pre-defined radio network temporary identifier (RNTI) (e.g., SI-RNTI or a configured RNTI) . In some aspects, the on-demand-SI-RNTI may be configured by the network entity 104b or the network entity 104a via MIB, SIB, UL-WUS configuration, the response to the on-demand SIB1 request, or the UL-WUS. The on-demand-SI-RNTI may allow the UE 102 to differentiate between a periodic SIB1 and the on-demand SIB1. If the UE 102 receives the on-demand SIB1 with the on-demand-SI-RNTI, the UE is aware that the UL-WUS requesting the on-demand SIB1 was received correctly by the network entity 104a. The network entity 104b may transmit the PDSCH 633 QCLed with an SSB 630 based on one or more parameters including average delay, delay spread, Doppler shift, Doppler spread, spatial reception parameters, and/or antenna gain.

FIG. 7 is a signaling diagram 700 illustrating on-demand SIB1 transmission according to an embodiment. In some aspects, the second network entity 104b (e.g., NES network entity) may transmit 710, to the UE 102, a SIB1. The SIB1 may optionally include SIB1 status information. For example, the SIB1 may include a value tag of SIB1 (e.g. a hash function of the SIB1) and/or an effective time of the SIB1. The UE 102 may enter 720 an RRC idle state or an RRC inactive state. In some aspects, the second network entity 104b may optionally transmit 715, to the first network entity 104a, the SIB1. The SIB1 may optionally include the SIB1 status information (e.g., value tag and/or effective time of the SIB1) .

In some aspects, the first network entity 104a may transmit 730, to the UE 102, a configuration (e.g., a first configuration) for an UL-WUS for second network entity 104b optionally including status information of the SIB1. The UL-WUS may be used by the UE 102 for requesting an on-demand SIB1 associated with the second network entity 104b.

In some aspects, the UE 102 may transmit 740, to the first network entity 104a, the UL-WUS (e.g., a PRACH signal) requesting an on-demand SIB1 from second network entity 104b. The UE 102 may transmit 740 the UL-WUS based on status information of the on-demand SIB1. For example, as described with reference to FIG. 3, the status information may be based on the value tag associated with the SIB1 being different from the value tag associated with the on-demand SIB1. In some aspects, the status information is based on the effective time period of the SIB1 as described with reference to FIG. 4. In some other aspects, the UE 102 may transmit, to the second network entity 104b, a UL-WUS (e.g., a PRACH signal) requesting an on-demand SIB1 from the second network entity 104b.

In some aspects, the first network entity 104a may transmit 750, to the UE 102, a response to the UL-WUS indicating a configuration for SIB1 monitoring or a configuration to access first network entity 104a. For example, the response may indicate a configuration for on-demand SIB1 monitoring as described with reference to FIGs. 5 and 6. In some aspects, the response may indicate a configuration to access the first network entity as described with reference to FIG. 5.

In some aspects, the first network entity 104a may optionally transmit 755, to the second network entity 104b, a network entity WUS. The network entity 104a may transmit (e.g., forward) , to the second network entity 104b, the network entity WUS and the request for the on-demand SIB1 as described with reference to FIGs. 3 and 4.

In some aspects, the second network entity 104b may transmit 760, to the UE 102, the on-demand SIB1 based on the SIB1 monitoring configuration. The second network entity 104b may transmit 760 the on-demand SIB1 in response to receiving the on-demand SIB1 request.

In some aspects, the UE 102 may optionally transmit 770a, to the first network entity 104a, a PRACH for initial access to the network entity 104a. The UE 102 may optionally transmit 770a the PRACH for initial access to the network entity 104a as described with reference to FIG. 5.

In some aspects, the UE 102 may optionally transmit 770b, to the second network entity 104b, a PRACH for initial access to the network entity 104b. The UE 102 may optionally transmit 770b the PRACH for initial access to the network entity 104b based on the on-demand SIB1 or the previously received 710 SIB1 based on whether the SIB1 has changed or not.

FIG. 8 is a signaling diagram 800 illustrating on-demand SIB1 transmission and network entity initial access according to an embodiment. In some aspects, the UE 102 may transmit 740, to the first network entity 104a, the UL-WUS requesting an on-demand SIB1 from second network entity. The UL-WUS may include a PRACH signal (e.g., a RA preamble) . The UE 102 may transmit 740 the UL-WUS based on status information of the on-demand SIB1. For example, as described with reference to FIG. 3, the status information may be based on the value tag associated with the SIB1 being different from the value tag associated with the on-demand SIB1. In some aspects, the status information is based on the effective time period of the SIB1 as described with reference to FIG. 4.

In some aspects, the first network entity 104a may transmit 825, to the UE 102, a RAR scheduling a PUSCH for message 3 (Msg3) transmission. The RAR may be referred to as message 2 (Msg2) .

In some aspects, the UE 102 may transmit 835, to the first network entity 104a, a Msg3 (e.g., via the scheduled PUSCH) including a MAC CE for on-demand SIB1 request for the second network entity. For example, UE 102 may transmit 835, to the first network entity 104a, the Msg3 as described with reference to FIG. 5.

In some aspects, the first network entity 104a may transmit 845, to the UE 102, a Msg4 (e.g., via PDSCH) including a response to the on-demand SIB1 request indicating the UE 102 to access network entity 104a or to monitor for the on-demand SIB 1. For example, the first network entity 104a may transmit 845 the Msg4 as described with reference to FIG. 5.

FIGs. 9-11 show methods for implementing one or more aspects of FIGs. 2-8. In particular, FIG. 9 shows an implementation by the UE 102 of the one or more aspects of FIGs. 2-8. FIG. 10 shows an implementation by a first network entity 104 of the one or more aspects of FIGs. 2-8. FIG. 11 shows an implementation by a second (NES) network entity 104 of the one or more aspects of FIGs. 2-8.

FIG. 9 illustrates a flowchart 900 of a method of wireless communication at a UE. With reference to FIGs. 1-8, the method may be performed by the UE 102. In embodiments, the UE receives 910, from a second network entity, a first SIB1. For example, referring to FIG. 7, the UE 102 receives 710, from a second network entity 104b, a first SIB1 optionally including a SIB1 value tag or SIB1 effective time.

In embodiments, the UE receives 930, from a first network entity, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. For example, referring to FIG. 7, the UE 102 receives 730, from the network entity 104a, a configuration for an UL-WUS for network entity 104b optionally including status information of SIB1.

In embodiments, the UE transmits 940, to the first network entity, the UL-WUS based on status information of the SIB1. For example, referring to FIG. 7, the UE 102 transmits 740, to the first network entity 104a, an UL-WUS to request an on-demand SIB1 from second network entity 104b.

In embodiments, the UE receives 950, from the first network entity, a response indicating a second configuration for monitoring the SIB1 from the second network entity. For example, referring to FIG. 7, the UE 102 receives 750, from the network entity 104a, a response to the UL-WUS indicating a configuration for SIB1 monitoring or a configuration to access first network entity 104a. In embodiments, the UE receives 960, from the second network entity, the SIB1 via a physical downlink shared channel, PDSCH, based on the second configuration. For example, referring to FIG. 7, the UE 102 receives 760, from the network entity 104b, the on-demand SIB1 based on configured SIB1 monitoring configuration.

In embodiments, the UE optionally transmits 970, to the first or second network entity, a physical random access channel, PRACH, signal for initial access. For example, referring to FIG. 7, the UE 102 optionally transmits 770a, to the first network entity 104a, a PRACH for initial access procedure. For example, referring to FIG. 7, the UE 102 optionally transmits 770b, to the second network entity 104b, a PRACH for initial access procedure.

FIG. 9 describes a method from a UE-side of a wireless communication link, whereas FIGs. 10-11 describe a method from a network-side of the wireless communication link.

FIG. 10 is a flowchart 1000 of a method of wireless communication at a first network entity. With reference to FIGs. 1-8, the method may be performed by one or more network entities 104, which may correspond to a base station or a unit of the base station, such as the RU 106, the DU 108, and/or the CU 110. In embodiments, the first network entity optionally receives 1015, from the second network entity, a SIB1 optionally including status information of the SIB1. For example, referring to FIG. 7, the first network entity 104a optionally receives 715, from the second network entity 104b, a SIB1 optionally including status information of the SIB1.

In embodiments, the first network entity transmits 1030, to a UE, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. For example, referring to FIG. 7, the first network entity 104a transmits 730, to the UE 102, a configuration for an UL-WUS for the second network entity 104b optionally including status information of SIB1.

In embodiments, the first network entity receives 1040, from the UE, the UL-WUS based on the status information of the SIB1. For example, referring to FIG. 7, the first network entity 104a receives 740, from the UE 102, an UL-WUS to request an on-demand SIB1 from the second network entity 104b.

In embodiments, the first network entity transmits 1050, to the UE, a response indicating a second configuration for monitoring the SIB1 from the second network entity. For example, referring to FIG. 7, the first network entity 104a transmits 750, to the UE 102, a response to the UL-WUS indicating a configuration for SIB1 monitoring or a configuration to access first network entity 104a.

In embodiments, the first network entity optionally receives 1070, from the UE, a PRACH signal for initial access. For example, referring to FIG. 7, the first network entity 104a optionally receives 770a, from the UE 102, a PRACH signal for initial access.

FIG. 11 is a flowchart 1100 of a method of wireless communication at a second network entity. With reference to FIGs. 1-8, the method may be performed by one or more network entities 104, which may correspond to a base station or a unit of the base station, such as the RU 106, the DU 108, and/or the CU 110. In embodiments, the second network entity transmits 1110, to a UE, a first SIB1, associated with the second network entity. For example, referring to FIG. 7, the second network entity 104b transmits 710, to the UE 102, a SIB1 optionally including a SIB1 value tag or a SIB1 effective time.

In embodiments, the second network entity optionally transmits 1115, to a first network entity, status information associated with the SIB1. For example, referring to FIG. 7, the second network entity 104b optionally transmits 715, to the first network entity 104a, a SIB1 optionally including a SIB1 value tag or SIB1 effective time.

In embodiments, the second network entity receives 1155, from the first network entity, a network entity wakeup signal. For example, referring to FIG. 7, the second network entity 104b receives 755, from the first network entity 104a, a network entity wakeup signal.

In embodiments, the second network entity, responsive to receiving the network entity wakeup signal, transmits 1160, to the UE, a second SIB1 associated with the second network entity, the second SIB1 being different from the first SIB1. For example, referring to FIG. 7, the second network entity 104b, transmits 760, to the UE 102, the on-demand SIB1 based on the SIB1 monitoring configuration.

In embodiments, the second network entity optionally receives 1170, from the UE, a PRACH signal for initial access. For example, referring to FIG. 7, the second network entity 104b optionally receives 770b, from the UE 102, a PRACH signal for initial access.

A UE apparatus 1202, as described in FIG. 12, may perform the method of the flowchart of FIG. 9. The one or more network entities 104, as described in FIG. 13, may perform the method of the flowcharts of FIGs. 10 and 11.

FIG. 12 is a diagram 1200 illustrating an example of a hardware implementation for a UE apparatus 1202. The UE apparatus 1202 may be the UE 102, a component of the UE 102, or may implement UE functionality. The UE apparatus 1202 may include an application processor 1206, which may have on-chip memory 1206’. In examples, the application processor 1206 may be coupled to a secure digital (SD) card 1208 and/or a display 1210. The application processor 1206 may also be coupled to a sensor (s) module 1212, a power supply 1214, an additional module of memory 1216, a camera 1218, and/or other related components. For example, the sensor (s) module 1212 may control a barometric pressure sensor/altimeter, a motion sensor such as an inertial management unit (IMU) , a gyroscope, accelerometer (s) , a light detection and ranging (LIDAR) device, a radio-assisted detection and ranging (RADAR) device, a sound navigation and ranging (SONAR) device, a magnetometer, an audio device, and/or other technologies used for positioning.

The UE apparatus 1202 may further include a wireless baseband processor 1226, which may be referred to as a modem. The wireless baseband processor 1226 may have on-chip memory 1226'. Along with, and similar to, the application processor 1206, the wireless baseband processor 1226 may also be coupled to the sensor (s) module 1212, the power supply 1214, the additional module of memory 1216, the camera 1218, and/or other related components. The wireless baseband processor 1226 may be additionally coupled to one or more subscriber identity module (SIM) card (s) 1220 and/or one or more transceivers 1230 (e.g., wireless RF transceivers) .

Within the one or more transceivers 1230, the UE apparatus 1202 may include a Bluetooth module 1232, a WLAN module 1234, an SPS module 1236 (e.g., GNSS module) , and/or a cellular module 1238. The Bluetooth module 1232, the WLAN module 1234, the SPS module 1236, and the cellular module 1238 may each include an on-chip transceiver (TRX) , or in some cases, just a transmitter (TX) or just a receiver (RX) . The Bluetooth module 1232, the WLAN module 1234, the SPS module 1236, and the cellular module 1238 may each include dedicated antennas and/or utilize antennas 1240 for communication with one or more other nodes. For example, the UE apparatus 1202 can communicate through the transceiver (s) 1230 via the antennas 1240 with another UE (e.g., sidelink communication) and/or with a network entity 104 (e.g., uplink/downlink communication) , where the network entity 104 may correspond to a base station or a unit of the base station, such as the RU 106, the DU 108, or the CU 110.

The wireless baseband processor 1226 and the application processor 1206 may each include a computer-readable medium /memory 1226', 1206', respectively. The additional module of memory 1216 may also be considered a computer-readable medium /memory. Each computer-readable medium /memory 1226', 1206', 1216 may be non-transitory. The wireless baseband processor 1226 and the application processor 1206 may each be responsible for general processing, including execution of software stored on the computer-readable medium /memory 1226', 1206', 1216. The software, when executed by the wireless baseband processor 1226 /application processor 1206, causes the wireless baseband processor 1226 /application processor 1206 to perform the various functions described herein. The computer-readable medium /memory may also be used for storing data that is manipulated by the wireless baseband processor 1226 /application processor 1206 when executing the software. The wireless baseband processor 1226 /application processor 1206 may be a component of the UE 102. The UE apparatus 1202 may be a processor chip (e.g., modem and/or application) and include just the wireless baseband processor 1226 and/or the application processor 1206. In other examples, the UE apparatus 1202 may be the entire UE 102 and include the additional modules of the apparatus 1202.

As discussed in FIG. 1 and implemented with respect to FIG. 9, the on-demand SIB1 component 140 is configured to receive, from a first network entity, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The on-demand SIB1 component 140 is further configured to transmit, to the first network entity, the UL-WUS based on status information of the SIB1. The on-demand SIB1 component 140 is further configured to receive, from the first network entity, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

The on-demand SIB1 component 140 may be within the application processor 1206 (e.g., at 140a) , the wireless baseband processor 1226 (e.g., at 140b) , or both the application processor 1206 and the wireless baseband processor 1226. The on-demand SIB1 component 140a-140b may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by the one or more processors, or a combination thereof.

FIG. 13 is a diagram 1300 illustrating an example of a hardware implementation for one or more network entities 104. The one or more network entities 104 may be a base station, a component of a base station, or may implement base station functionality. The one or more network entities 104 may include, or may correspond to, at least one of the RU 106, the DU, 108, or the CU 110. The CU 110 may include a CU processor 1346, which may have on-chip memory 1346'. In some aspects, the CU 110 may further include an additional module of memory 1356 and/or a communications interface 1348, both of which may be coupled to the CU processor 1346. The CU 110 can communicate with the DU 108 through a midhaul link 162, such as an F1 interface between the communications interface 1348 of the CU 110 and a communications interface 1328 of the DU 108.

The DU 108 may include a DU processor 1326, which may have on-chip memory 1326'. In some aspects, the DU 108 may further include an additional module of memory 1336 and/or the communications interface 1328, both of which may be coupled to the DU processor 1326. The DU 108 can communicate with the RU 106 through a fronthaul link 160 between the communications interface 1328 of the DU 108 and a communications interface 1308 of the RU 106.

The RU 106 may include an RU processor 1306, which may have on-chip memory 1306'. In some aspects, the RU 106 may further include an additional module of memory 1316, the communications interface 1308, and one or more transceivers 1330, all of which may be coupled to the RU processor 1306. The RU 106 may further include antennas 1340, which may be coupled to the one or more transceivers 1330, such that the RU 106 can communicate through the one or more transceivers 1330 via the antennas 1340 with the UE 102.

The on-chip memory 1306', 1326', 1346' and the additional modules of memory 1316, 1336, 1356 may each be considered a computer-readable medium /memory. Each computer-readable medium /memory may be non-transitory. Each of the processors 1306, 1326, 1346 is responsible for general processing, including execution of software stored on the computer-readable medium /memory. The software, when executed by the corresponding processor (s) 1306, 1326, 1346 causes the processor (s) 1306, 1326, 1346 to perform the various functions described herein. The computer-readable medium /memory may also be used for storing data that is manipulated by the processor (s) 1306, 1326, 1346 when executing the software. In examples, the on-demand SIB1 configuration component 150 may sit at any of the one or more network entities 104, such as at the CU 110; both the CU 110 and the DU 108; each of the CU 110, the DU 108, and the RU 106; the DU 108; both the DU 108 and the RU 106; or the RU 106.

As discussed in FIG. 1 and implemented with respect to FIG. 10, the on-demand SIB1 configuration component 150 is configured to transmit, to a UE, a first configuration configuring an UL-WUS for requesting a SIB1 associated with a second network entity. The on-demand SIB1 configuration component 150 is further configured to receive, from the UE, the UL-WUS based on status information of the SIB1. The on-demand SIB1 configuration component 150 is further configured to transmit, to the UE, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

As discussed in FIG. 1 and implemented with respect to FIG. 11, the on-demand SIB1 configuration component 150 is configured to transmit, to a UE, a first SIB1 associated with the second network entity. The on-demand SIB1 configuration component 150 is further configured to receive, from a first network entity, a network entity wakeup signal. The on-demand SIB1 configuration component 150 is further configured to transmit, to the UE in response to receiving the network entity wakeup signal, a second SIB1 associated with the second network entity, the second SIB1 being different from the first SIB1. The on-demand SIB1 configuration component 150 is further configured to receive, from the UE, a PRACH signal for initial access based on the second SIB1.

The on-demand SIB1 configuration component 150 may be within one or more processors of the one or more network entities 104, such as the RU processor 1306 (e.g., at 150a) , the DU processor 1326 (e.g., at 150b) , and/or the CU processor 1346 (e.g., at 150c) . The on-demand SIB1 configuration component 150a-150c may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors 1306, 1326, 1346 configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by the one or more processors 1306, 1326, 1346, or a combination thereof.

The specific order or hierarchy of blocks in the processes and flowcharts disclosed herein is an illustration of example approaches. Hence, the specific order or hierarchy of blocks in the processes and flowcharts may be rearranged. Some blocks may also be combined or deleted. Dashed lines may indicate optional elements of the diagrams. The accompanying method claims present elements of the various blocks in an example order, and are not limited to the specific order or hierarchy presented in the claims, processes, and flowcharts.

The detailed description set forth herein describes various configurations in connection with the drawings and does not represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough explanation of various concepts. However, these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Aspects of wireless communication systems, such as telecommunication systems, are presented with reference to various apparatuses and methods. These apparatuses and methods are described in the following detailed description and are illustrated in the accompanying drawings by various blocks, components, circuits, processes, call flows, systems, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

An element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs) , central processing units (CPUs) , application processors, digital signal processors (DSPs) , reduced instruction set computing (RISC) processors, systems-on-chip (SoC) , baseband processors, field programmable gate arrays (FPGAs) , programmable logic devices (PLDs) , state machines, gated logic, discrete hardware circuits, and other similar hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software, which may be referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, or any combination thereof.

If the functionality described herein is implemented in software, the functions may be stored on, or encoded as, one or more instructions or code on a computer-readable medium, such as a non-transitory computer-readable storage medium. Computer-readable media includes computer storage media and can include a random-access memory (RAM) , a read-only memory (ROM) , an electrically erasable programmable ROM (EEPROM) , optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of these types of computer-readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer. Storage media may be any available media that can be accessed by a computer.

Aspects, implementations, and/or use cases described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, the aspects, implementations, and/or use cases may come about via integrated chip implementations and other non-module-component based devices, such as end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, artificial intelligence (AI) -enabled devices, machine learning (ML) -enabled devices, etc. The aspects, implementations, and/or use cases may range from chip-level or modular components to non-modular or non-chip-level implementations, and further to aggregate, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more techniques described herein.

Devices incorporating the aspects and features described herein may also include additional components and features for the implementation and practice of the claimed and described aspects and features. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes, such as hardware components, antennas, RF-chains, power amplifiers, modulators, buffers, processor (s) , interleavers, adders/summers, etc. Techniques described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, etc., of varying configurations.

The description herein is provided to enable a person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not limited to the aspects described herein, but are to be interpreted in view of the full scope of the present disclosure consistent with the language of the claims.

Reference to an element in the singular does not mean “one and only one” unless specifically stated, but rather “one or more. ” Terms such as “if, ” “when, ” and “while” do not imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when, ” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The terms “may” , “might” , and “can” , as used in this disclosure, often carry certain connotations. For example, “may” refers to a permissible feature that may or may not occur, “might” refers to a feature that probably occurs, and “can” refers to a capability (e.g., capable of) . The phrase “For example” often carries a similar connotation to “may” and, therefore, “may” is sometimes excluded from sentences that include “for example” or other similar phrases.

Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C” or “one or more of A, B, or C” include any combination of A, B, and/or C, such as A and B, A and C, B and C, or A and B and C, and may include multiples of A, multiples of B, and/or multiples of C, or may include A only, B only, or C only. Sets should be interpreted as a set of elements where the elements number one or more. Terms or articles such as “a” , “an” , and/or “the” may refer to one of an item, feature, element, etc., that the term or article precedes, or may refer to more than one of said item, feature, element, etc. that the term or article precedes. For example, the recitation “a widget” does not preclude reference to multiples of said widget, as “multiple widgets” necessarily includes “a widget” . Hence, the recitation “a widget” may be interpreted as “at least one widget” or, similarly, interpreted as “one or more widgets” .

Unless otherwise specifically indicated, ordinal terms such as “first” and “second” do not necessarily imply an order in time, sequence, numerical value, etc., but are used to distinguish between different instances of a term or phrase that follows each ordinal term.

Reference numbers, as used in the specification and figures, are sometimes cross-referenced among drawings to denote same or similar features. A feature that is exactly the same in multiple drawings may be labeled with the same reference number in the multiple drawings. A feature that is similar among the multiple drawings, but not exactly the same, may be labeled with reference numbers that have different leading numbers but have one or more of the same trailing numbers (e.g., 206, 306, 406, etc., may refer to similar features in the drawings) . Hence, like numbers may refer to like actions.

Structural and functional equivalents to elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are encompassed by the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ” As used herein, the phrase “based on” shall not be construed as a reference to a closed set of information, one or more conditions, one or more factors, or the like. In other words, the phrase “based on A” , where “A” may be information, a condition, a factor, or the like, shall be construed as “based at least on A” unless specifically recited differently.

The following examples are illustrative only and may be combined with other examples or teachings described herein, without limitation.

Example 1 is a method of wireless communication at a UE, comprising receiving, from a first network entity, a first configuration configuring an uplink-wakeup signal, UL-WUS for requesting system information block type 1, SIB1, associated with a second network entity; transmitting, to the first network entity, the UL-WUS based on status information of the SIB1; and receiving, from the first network entity, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

Example 2 may be combined with Example 1 and includes wherein the UL-WUS comprises a physical random access channel, PRACH, signal.

Example 3 may be combined with any of Examples 1-2 and further includes the transmitting the UL-WUS comprises transmitting the PRACH signal via dedicated PRACH resources based on at least one of: a physical cell identifier, PCI, associated with the second network entity; a carrier frequency associated with the SIB1; or a synchronization signal block, SSB, index quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1.

Example 4 may be combined with any of Examples 1-3 and further includes the transmitting the UL-WUS comprises transmitting the PRACH signal via non-dedicated PRACH resources, the method further comprising: receiving, from the first network entity in response to the PRACH signal, a random access response, RAR, scheduling a physical uplink shared channel, PUSCH, communication; and transmitting, to the first network entity, the PUSCH communication indicating at least one of: a physical cell identifier, PCI, associated with the second network entity; one or more synchronization signal blocks, SSBs, that are quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1; first measurement information associated with the first network entity and second measurement information associated with the second network entity; a carrier frequency associated with the SIB1; or a time window for the monitoring the SIB1; and receiving, from the first network entity in response to the PUSCH communication, a physical downlink shared channel, PDSCH, communication indicating the UE to monitor for the SIB1 or perform an initial access procedure with the first network entity.

Example 5 may be combined with any of Examples 1-4 and further includes the SIB1 associated with the second network entity includes an on-demand SIB1, the method further comprising: receiving, from the first network entity, a second SIB1; and obtaining an indicator indicating whether the second SIB1 is different from the on-demand SIB1, wherein the status information is based on the second SIB1 being different from the on-demand SIB1.

Example 6 may be combined with any of Examples 1-4 and further includes receiving, from the second network entity, the SIB1 via a physical downlink shared channel, PDSCH, based on the second configuration.

Example 7 may be combined with any of Examples 1-6 and further includes receiving, from the second network entity, a synchronization signal block, SSB, associated with the on-demand SIB1.

Example 8 may be combined with any of Examples 1-7 and further includes the SIB1 associated with the second network entity includes an on-demand SIB1, the method further comprising: prior to the receiving the first configuration, receiving, from the second network entity, a first SIB1; obtaining a value tag associated with the first SIB1; and obtaining a value tag associated with the on-demand SIB1, wherein the status information is based on the value tag associated with the first SIB1 being different from the value tag associated with the on-demand SIB1.

Example 9 may be combined with any of Examples 1-8 and further includes refraining from the transmitting the UL-WUS, wherein the status information is based on the value tag associated with the first SIB1 being a same as the value tag associated with the on-demand SIB1.

Example 10 may be combined with any of Examples 1-9 and further includes the value tag associated with the first SIB1 comprises a hash function of the first SIB1; and the value tag associated with the on-demand SIB1 comprises a hash function of the on-demand SIB1.

Example 11 may be combined with any of Examples 1-10 and further includes prior to receiving the first configuration, receiving, from the second network entity, a first SIB1 having an effective time period, wherein the status information is based on the effective time period for the first SIB1.

Example 12 may be combined with any of Examples 1-11 and further includes at least one of: receiving, from the first network entity, an indicator of the effective time period via the first configuration; or receiving, from the second network entity, the indicator of the effective time period via at least one of: the first SIB1; a second SIB1; a master information block, MIB; or a physical downlink control channel, PDCCH, scheduling the first SIB1.

Example 13 may be combined with any of Examples 1-12 and further includes the transmitting the UL-WUS comprises transmitting the UL-WUS based on at least one of: the first measurement information associated with the first network entity; or the second measurement information associated with the second network entity.

Example 14 may be combined with any of Examples 1-13 and further includes transmitting, to the first network entity, the first measurement information associated with the first network entity and the second measurement information associated with the second network entity; transmitting, to the first network entity, a physical random access channel, PRACH, signal for initial access; performing an initial access procedure with the first network entity based on the third configuration to access the first network entity when at least one of: a reference signal received power, RSRP, associated with the first network entity is greater than an RSRP associated with the second network entity minus a first offset; a signal plus interference to noise ratio, SINR, associated with the first network entity is greater than an SINR associated with the second network entity minus a second offset; a reference signal received quality, RSRQ, associated with the first network entity is greater than an RSRQ associated with the second network entity minus a third offset; the RSRP associated with the first network entity is greater than a first threshold; the SINR associated with the first network entity is greater than a second threshold; the RSRQ associated with the first network entity is greater than a third threshold; the RSRP associated with the second network entity is less than a fourth threshold; the SINR associated with the second network entity is less than a fifth threshold; or the RSRQ associated with the second network entity is less than a sixth threshold.

Example 15 may be combined with any of Examples 1-14 and further includes receiving the response via a medium access control-control element, MAC-CE, associated with at least one of: a first random access response, RAR, type to configure the UE to monitor the SIB1 from the second network entity; or a second RAR type to configure the UE to access the first network entity.

Example 16 may be combined with any of Examples 1-15 and further includes the SIB1 associated with the second network entity includes an on-demand SIB1 and the response further indicates at least one of: a receive acknowledgement for the UL- WUS; a backoff indicator for the UE to perform an initial access procedure for the first network entity; a physical cell identifier, PCI, associated with the second network entity; a carrier frequency associated with the on-demand SIB1; one or more first synchronization signal blocks, SSBs that are quasi-colocated, QCLed with a physical downlink shared channel, PDSCH, carrying the on-demand SIB1; one or more second SSBs that are QCLed with a physical downlink control channel, PDCCH, scheduling the PDSCH carrying the on-demand SIB1; a value tag associated with the on-demand SIB1; timing information for monitoring the on-demand SIB1; a retransmission configuration for the UL-WUS; or a downlink assignment for the PDSCH carrying the on-demand SIB1.

Example 17 may be combined with any of Examples 1-16 and further includes the UE refrains from receiving the PDCCH scheduling the PDSCH carrying the on-demand SIB1 and the downlink assignment indicates at least one of: a frequency domain resource assignment, FDRA, for the PDSCH; a time domain resource assignment, TDRA, for the PDSCH; a virtual resource block, VRB, to physical resource block, PRB, mapping for the PDSCH; a modulation and coding scheme, MCS, for the PDSCH; a redundancy version, RV, for the PDSCH; an index of a reference slot for the PDSCH; a periodicity for the reference slot for the PDSCH; a slot offset from the reference slot for the PDSCH; or a number of retransmissions for the PDSCH.

Example 18 may be combined with any of Examples 1-17 and further includes the receiving the first configuration for comprises receiving the first configuration for the UL-WUS when the UE is in a radio resource control, RRC, idle state or an RRC inactive state; the transmitting the UL-WUS comprises transmitting the UL-WUS when the UE is in the RRC idle state or the RRC inactive state; and the receiving the response comprises receiving the response to the UL-WUS when the UE is in the RRC idle state or the RRC inactive state.

Example 19 is a method of wireless communication at a first network entity, comprising transmitting, to a user equipment, UE, , a first configuration configuring an uplink-wakeup signal, UL-WUS for requesting system information block type 1, SIB1, associated with a second network entity; receiving, from the UE, the UL-WUS based on status information of the SIB1; and transmitting, to the UE, a response indicating a second configuration for monitoring the SIB1 from the second network entity.

Example 20 may be combined with Example 19 and includes the UL-WUS comprises a physical random access channel, PRACH, signal.

Example 21 may be combined with any of Examples 19-20 and further includes the receiving the UL-WUS comprises receiving the PRACH signal via dedicated PRACH resources based on at least one of: a physical cell identifier, PCI, associated with the second network entity; carrier frequency associated with the SIB1; or a synchronization signal block, SSB, index quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1.

Example 22 may be combined with any of Examples 19-21 and further includes the receiving the UL-WUS comprises receiving the PRACH signal via non-dedicated PRACH resources, the method further comprising: transmitting, to the UE in response to the PRACH, a random access response, RAR, scheduling a physical uplink shared channel, PUSCH, communication; and receiving, from the UE, the PUSCH communication indicating at least one of: physical cell identifier, PCI, associated with the second network entity; one or more synchronization signal blocks, SSBs, that are quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1; first measurement information associated with the first network entity and second measurement information associated with the second network entity; carrier frequency associated with the SIB1; or a time window for the monitoring the SIB1; and transmitting, to the UE in response to the PUSCH communication, a physical downlink shared channel, PDSCH, communication indicating the UE to monitor for the SIB1 or perform an initial access procedure with the first network entity.

Example 23 may be combined with any of Examples 19-22 and further includes the SIB1 associated with the second network entity includes an on-demand SIB1, the method further comprising: transmitting, to the UE, a second SIB1 associated with the first network entity; and an indicator of whether the second SIB1 is different from the on-demand SIB1, wherein the status information is based on the second SIB1 being different from the on-demand SIB1.

Example 24 may be combined with any of Examples 19-23 and further includes receiving, from the second network entity, a value tag associated with the SIB1; and transmitting, to the UE, the value tag associated with the SIB1, wherein the status information is based on the value tag.

Example 25 may be combined with any of Examples 19-24 and further includes the value tag associated with the SIB1 comprises a hash function of the SIB1.

Example 26 may be combined with any of Examples 19-25 and further includes receiving, from the second network entity, an effective time period for a first SIB1 associated with the second network entity, wherein: the first configuration for the UL-WUS indicates the effective time period; and wherein the status information is based on the effective time period.

Example 27 may be combined with any of Examples 19-26 and further includes the receiving the UL-WUS comprises receiving the UL-WUS based on at least one of:first measurement information associated with the first network entity; or second measurement information associated with the second network entity.

Example 28 may be combined with any of Examples 19-27 and further includes receiving, from the UE, first measurement information associated with the first network entity and second measurement information associated with the second network entity; receiving, from the UE, a physical random access channel, PRACH, signal for initial access; performing an initial access procedure with the UE for the UE to access the first network entity when at least one of: a reference signal received power, RSRP, associated with the first network entity is greater than an RSRP associated with the second network entity minus a first offset; a signal plus interference to noise ratio, SINR, associated with the first network entity is greater than an SINR associated with the second network entity minus a second offset; a reference signal received quality, RSRQ, associated with the first network entity is greater than an RSRQ associated with the second network entity minus a third offset; the RSRP associated with the first network entity is greater than a first threshold; the SINR associated with the first network entity is greater than a second threshold; the RSRQ associated with the first network entity is greater than a third threshold; the RSRP associated with the second network entity is less than a fourth threshold; the SINR associated with the second network entity is less than a fifth threshold; or the RSRQ associated with the second network entity is less than a sixth threshold.

Example 29 may be combined with any of Examples 19-28 and further includes transmitting the response via a medium access control-control element, MAC-CE, associated with at least one of: a first random access response, RAR, type to configure the UE to monitor the SIB1 from the second network entity; or a second RAR type to configure the UE to access the first network entity.

Example 30 may be combined with any of Examples 19-29 and further includes the SIB1 associated with the second network entity includes an on-demand SIB1 and the response further indicates at least one of: a receive acknowledgement for the UL-WUS; a backoff indicator for the UE to perform an initial access procedure for the first network entity; a physical cell identifier, PCI, associated with the second network entity; a carrier frequency associated with the on-demand SIB1; one or more first synchronization signal blocks, SSBs that are quasi-colocated, QCLed with a physical downlink shared channel, PDSCH, carrying the on-demand SIB1; one or more second SSBs that are QCLed with a physical downlink control channel, PDCCH, scheduling the PDSCH carrying the on-demand SIB1; a value tag associated with the on-demand SIB1; timing information for monitoring the on-demand SIB1; a retransmission configuration for the UL-WUS; or a downlink assignment for the PDSCH carrying the on-demand SIB1.

Example 31 may be combined with any of Examples 19-30 and further includes the downlink assignment indicates at least one of: a frequency domain resource assignment, FDRA, for the PDSCH; a time domain resource assignment, TDRA, for the PDSCH; a virtual resource block, VRB, to physical resource block, PRB, mapping for the PDSCH; a modulation and coding scheme, MCS, for the PDSCH; a redundancy version, RV, for the PDSCH; an index of a reference slot for the PDSCH; a periodicity for the reference slot for the PDSCH; a slot offset from the reference slot for the PDSCH; or a number of retransmissions for the PDSCH.

Example 32 is a method of wireless communication at a second network entity, comprising transmitting, to a user equipment, UE, a first system information block type 1, SIB1, associated with the second network entity; receiving, from a first network entity, a network entity wakeup signal; responsive to receiving the network entity wakeup signal, transmitting, to the UE, a second SIB1 associated with the second network entity, the second SIB1 being different from the first SIB1; and receiving, from the UE, a physical random access channel, PRACH, signal for initial access based on the second SIB1.

Example 33 may be combined with Examples 32 and further includes entering a network energy saving, NES, mode after the transmitting the first SIB1.

Example 34 may be combined with any of Examples 32-33 and further includes the transmitting, the second SIB1 comprises transmitting the second SIB1 via a physical downlink shared channel, PDSCH.

Example 35 may be combined with any of Examples 32-34 and further includes transmitting, to the UE, a synchronization signal block, SSB, associated with the second SIB1.

Example 36 may be combined with any of Examples 32-35 and further includes transmitting, to the UE, a value tag associated with the first SIB1; and transmitting, to a first network entity, a value tag associated with the second SIB1, wherein the transmitting the second SIB1 is based on the value tag associated with the first SIB1 being different from the value tag associated with the second SIB1.

Example 37 may be combined with any of Examples 32-36 and further includes the value tag associated with the first SIB1 comprises a hash function of the first SIB1; and the value tag associated with the second SIB1 comprises a hash function of the second SIB1.

Example 38 may be combined with any of Examples 32-37 and further includes transmitting, to the UE, an indicator of an effective time period for the first SIB1, wherein the transmitting the second SIB1 comprises transmitting the second SIB1 after the effective time period for the first SIB1.

Example 39 may be combined with any of Examples 32-38 and further includes the transmitting the indicator of the effective time period for the first SIB1 comprises transmitting the indicator via at least one of: the first SIB1; a master information block, MIB; or a physical downlink control channel, PDCCH, scheduling the first SIB1.

Example 40 is an apparatus for wireless communication for implementing a method as in any of Examples 1-39.

Example 41 is an apparatus for wireless communication including means for implementing a method as in any of Examples 1-39.

Example 42 is a non-transitory computer-readable medium storing computer executable code, the code when executed by a processor causes the processor to implement a method as in any of Examples 1-39.

Claims

A method for wireless communication by a user equipment, UE, (102) , the method comprising:

receiving (730) , from a first network entity (104a) , a first configuration configuring an uplink-wakeup signal, UL-WUS for requesting system information block type 1, SIB1, associated with a second network entity (104b) ;

transmitting (740) , to the first network entity (104a) , the UL-WUS based on status information of the SIB1; and

receiving (750) , from the first network entity (104a) , a response indicating a second configuration for monitoring the SIB1 from the second network entity (104b) .
The method of claim 1, wherein the UL-WUS comprises a physical random access channel, PRACH, signal.
The method of claim 2, wherein the transmitting (740) the UL-WUS comprises transmitting (740) the PRACH signal via dedicated PRACH resources based on at least one of:

a physical cell identifier, PCI, associated with the second network entity (104b) ;

a carrier frequency associated with the SIB1; or

a synchronization signal block, SSB, index quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1.
The method of claim 2, wherein the transmitting (740) the UL-WUS comprises transmitting (740) the PRACH signal via non-dedicated PRACH resources, the method further comprising:

receiving (825) , from the first network entity (104a) in response to the PRACH signal, a random access response, RAR, scheduling a physical uplink shared channel, PUSCH, communication; and

transmitting (835) , to the first network entity (104a) , the PUSCH communication indicating at least one of:

a physical cell identifier, PCI, associated with the second network entity (104b) ;

one or more synchronization signal blocks, SSBs, that are quasi-colocated, QCLed, with a physical downlink shared channel, PDSCH, carrying the SIB1;

first measurement information associated with the first network entity (104a) and second measurement information associated with the second network entity (104b) ;

a carrier frequency associated with the SIB1; or

a time window for the monitoring the SIB1; and

receiving (845) , from the first network entity (104a) in response to the PUSCH communication, a physical downlink shared channel, PDSCH, communication indicating the UE (102) to monitor for the SIB1 or perform an initial access procedure with the first network entity (104a) .
The method of any of claims 1 to 4, wherein the SIB1 associated with the second network entity includes an on-demand SIB1, the method further comprising:

receiving, from the first network entity (104a) , a second SIB1; and

obtaining an indicator indicating whether the second SIB1 is different from the on-demand SIB1, wherein the status information is based on the second SIB1 being different from the on-demand SIB1.
The method of any of claims 1 to 5, further comprising:

receiving (760) , from the second network entity (104b) , the SIB1 via a physical downlink shared channel, PDSCH, based on the second configuration.
The method of any of claims 1 to 6, wherein the SIB1 associated with the second network entity includes an on-demand SIB1, the method further comprising:

prior to the receiving the first configuration, receiving (710) , from the second network entity (104b) , a first SIB1;

obtaining a value tag associated with the first SIB1; and

obtaining a value tag associated with the on-demand SIB1, wherein the status information is based on the value tag associated with the first SIB1 being different from the value tag associated with the on-demand SIB1.
The method of claim 7, further comprising:

refraining from the transmitting the UL-WUS, wherein the status information is based on the value tag associated with the first SIB1 being a same as the value tag associated with the on-demand SIB1.
The method of any of claims 1 to 8, further comprising:

prior to receiving the first configuration, receiving (710) , from the second network entity (104b) , a first SIB1 having an effective time period, wherein the status information is based on the effective time period for the first SIB1.
The method of any of claims 1 to 9, further comprising:

receiving (750) the response via a medium access control-control element, MAC-CE, associated with at least one of:

a first random access response, RAR, type to configure the UE (102) to monitor the SIB1 from the second network entity (104b) ; or

a second RAR type to configure the UE (102) to access the first network entity (104a) .
The method of any of claims 1 to 10, wherein:

the receiving (730) the first configuration for comprises receiving (730) the first configuration for the UL-WUS when the UE (102) is in a radio resource control, RRC, idle state or an RRC inactive state;

the transmitting (740) the UL-WUS comprises transmitting (740) the UL-WUS when the UE (102) is in the RRC idle state or the RRC inactive state; and

the receiving (750) the response comprises receiving (750) the response to the UL-WUS when the UE (102) is in the RRC idle state or the RRC inactive state.
A method for wireless communication by first network entity (104a) , the method comprising:

transmitting (730) , to a user equipment, UE, (102) , a first configuration configuring an uplink-wakeup signal, UL-WUS for requesting system information block type 1, SIB1, associated with a second network entity (104b) ;

receiving (740) , from the UE (102) , the UL-WUS based on status information of the SIB1; and

transmitting (750) , to the UE (102) , a response indicating a second configuration for monitoring the SIB1 from the second network entity (104b) .
The method of claims 12, further comprising:

receiving (715) , from the second network entity (104b) , a value tag associated with the SIB1; and

transmitting, to the UE (102) , the value tag associated with the SIB1, wherein the status information is based on the value tag.
The method of any of claims 12 to 13, further comprising:

receiving (715) , from the second network entity (104b) , an effective time period for a first SIB1 associated with the second network entity (104b) , wherein:

the first configuration for the UL-WUS indicates the effective time period; and

wherein the status information is based on the effective time period.
A method for wireless communication by a second network entity (104b) , the method comprising:

transmitting (710) , to a user equipment, UE (102) , a first system information block type 1, SIB1, associated with the second network entity (104b) ;

receiving (755) , from a first network entity (104a) , a network entity wakeup signal;

responsive to receiving the network entity wakeup signal, transmitting (760) , to the UE (102) , a second SIB1 associated with the second network entity (104b) , the second SIB1 being different from the first SIB1; and

receiving, from the UE (102) , a physical random access channel, PRACH, signal for initial access based on the second SIB1.
The method of claim 15, further comprising:

transmitting (710) , to the UE (102) , a value tag associated with the first SIB1; and

transmitting, to a first network entity (104a) , a value tag associated with the second SIB1, wherein the transmitting (760) the second SIB1 is based on the value tag associated with the first SIB1 being different from the value tag associated with the second SIB1.
The method of any of claims 15 to 16, further comprising:

transmitting (710) , to the UE (102) , an indicator of an effective time period for the first SIB1, wherein the transmitting (760) the second SIB1 comprises transmitting (760) the second SIB1 after the effective time period for the first SIB1.
An apparatus for wireless communication comprising a transceiver, a memory, and a processor coupled to the memory and the transceiver, the apparatus being configured to implement a method as in any of claims 1-17.