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US-20260129572-A1 - METHOD AND APPARATUS FOR WAKE-UP SIGNAL TRANSMISSION FOR NETWORK ENERGY SAVING

US20260129572A1US 20260129572 A1US20260129572 A1US 20260129572A1US-20260129572-A1

Abstract

Various solutions for wake-up signal (WUS) transmission for network energy saving with respect to user equipment and network apparatus in mobile communications are described. An apparatus may receive information for waking up a sleeping cell from a network node. The apparatus may transmit a WUS to the network node based on the information to wake up the sleeping cell. The WUS is used to request a transition from no or reduced transmission or reception activity to active transmission or reception activity of a channel or a signal, or is used to trigger a synchronization signal block (SSB) or system information block (SIB) transmission.

Inventors

  • Chien-Chun Cheng
  • Wei-De Wu
  • Yi-Ju Liao
  • Cheng-Hsun Li

Assignees

  • MEDIATEK INC.

Dates

Publication Date
20260507
Application Date
20230320

Claims (20)

  1. 1 . A method, comprising: receiving, by a processor of an apparatus, information for waking up a sleeping cell from a network node; and transmitting, by the processor, a wake-up-signal (WUS) to the network node based on the information to wake up the sleeping cell, wherein the WUS is used to request a transition from no or reduced transmission or reception activity to active transmission or reception activity of a channel or a signal, or is used to trigger a synchronization signal block (SSB) or system information block (SIB) transmission.
  2. 2 . The method of claim 1 , further comprising: receiving, by the processor, at least one handover condition with a list of candidate cells from the network node before the network node enters a sleep mode or leaves the sleep mode; and determining, by the processor, a candidate cell to access based on the list of candidate cells.
  3. 3 . The method of claim 1 , further comprising: receiving, by the processor, an assistant information for a cell selection or a cell re-selection from the network node; and performing, by the processor, the cell selection or the cell re-selection based on the assistant information.
  4. 4 . The method of claim 3 , wherein the assistant information comprises a cellBarred bit for network energy savings in a master information block (MIB) or a system information block 1 (SIB1).
  5. 5 . The method of claim 4 , further comprising: ignoring, by the processor, the cellBarred bit in an event that the MIB or the SIB1 provides an indication to wake up the sleeping cell, wherein the apparatus has capability to transmit the WUS or to parse an early termination indication (ETI); or determining, by the processor, not to camp on the sleeping cell after reading the cellBarred bit.
  6. 6 . The method of claim 1 , further comprising: receiving, by the processor, an indication to select an omnidirectional beam from the network node; and performing, by the processor, an access procedure to access the sleeping cell by using the omnidirectional beam.
  7. 7 . The method of claim 1 , wherein the information comprises a specific physical random access channel (PRACH) configuration.
  8. 8 . The method of claim 1 , wherein the information comprises an SSB measurement timing configuration (SMTC) from a candidate cell.
  9. 9 . The method of claim 8 , further comprising: receiving, by the processor, a sleeping cell list from the candidate cell to determine the sleeping cell; or receiving, by the processor, a sleeping cell indication from the sleeping cell.
  10. 10 . The method of claim 1 , further comprising: storing, by the processor, the information; and performing, by the processor, a cell selection or a cell reselection according to the stored information, wherein the information is from the sleeping cell or from a candidate cell.
  11. 11 . The method of claim 10 , wherein the information comprises a sleeping cell list from the candidate cell or a unique RACH configuration from the sleeping cell.
  12. 12 . The method of claim 1 , further comprising: receiving, by the processor, an early termination indication (ETI) from the network node; and entering, by the processor, an idle mode or performing a cell selection or a cell reselection after receiving the ETI.
  13. 13 . The method of claim 1 , further comprising: starting, by the processor, a prohibit timer; and stopping, by the processor, transmitting another WUS when the prohibit timer is running.
  14. 14 . A method, comprising: transmitting, by a processor of an apparatus, information for waking up a sleeping cell to a user equipment (UE); and receiving, by the processor, a wake-up-signal (WUS) from the UE to wake up the sleeping cell, wherein the WUS is used to request a transition from no or reduced transmission or reception activity to active transmission or reception activity of a channel or a signal, or is used to trigger a synchronization signal block (SSB) or system information block (SIB) transmission.
  15. 15 . The method of claim 14 , further comprising: transmitting, by the processor, at least one handover condition with a list of candidate cells to the UE before entering a sleep mode or leaving the sleep mode.
  16. 16 . The method of claim 14 , further comprising: transmitting, by the processor, an assistant information for a cell selection or cell re-selection to the UE.
  17. 17 . The method of claim 16 , wherein the assistant information comprises a cellBarred bit for network energy savings in a master information block (MIB) or system information block 1 (SIB1).
  18. 18 . The method of claim 14 , wherein the information comprises a specific physical random access channel (PRACH) configuration.
  19. 19 . The method of claim 14 , wherein the information comprises an SSB measurement timing configuration (SMTC) from a candidate cell.
  20. 20 . The method of claim 14 , further comprising: transmitting, by the processor, an early termination indication (ETI) to the UE when the apparatus is in a sleep mode.

Description

CROSS REFERENCE TO RELATED PATENT APPLICATION(S) The present disclosure claims the priority benefit of U.S. Provisional Patent Application No. 63/321,856, filed on 21 Mar. 2022. The content of aforementioned application is herein incorporated by reference in its entirety. TECHNICAL FIELD The present disclosure is generally related to mobile communications and, more particularly, to wake-up signal transmission for network energy saving with respect to user equipment (UE) and network apparatus in mobile communications. BACKGROUND Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section. The fifth-generation (5G) network, despite its enhanced energy efficiency in bits per Joule (e.g., 417% more efficiency than a 4G network) due to its larger bandwidth and better spatial multiplexing capabilities, may consume over 140% more energy than a 4G network. For energy saving, 5G network may activate a sleep mode for a base station (BS) with low traffic loads. The sleep mode may turn off a power amplifier and other power-wasting components to save energy. When the traffic loads increase, network may deactivate the sleep mode for the base stations to balance the workload of neighboring base stations. In order to deactivate the sleep mode, a signal used to wake up a base station is defined as a base station-wake-up signal (BS-WUS). The base station may receive the signal from the core 5G network or user equipments (UEs). However, it is unclear how the BS-WUS mechanism works in convention technologies. Accordingly, how to transmit WUS becomes an important issue for the newly developed wireless communication network. Therefore, there is a need to provide proper schemes for WUS transmission for UE. SUMMARY The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter. An objective of the present disclosure is to propose solutions or schemes that address the aforementioned issues pertaining to transmit the wake-up signal (WUS) for network energy saving with respect to user equipment and network apparatus in mobile communications. In one aspect, a method may involve an apparatus receiving information for waking up a sleeping cell from a network node. The method may also involve the apparatus transmitting a WUS to the network node based on the information to wake up the sleeping cell. The WUS is used to request a transition from no or reduced transmission or reception activity to active transmission or reception activity of a channel or a signal, or is used to trigger a synchronization signal block (SSB) or system information block (SIB) transmission. In one aspect, a method may involve an apparatus transmitting information for waking up a sleeping cell to a user equipment (UE). The method may also involve the apparatus receiving a WUS from the UE to wake up the sleeping cell. The WUS is used to request a transition from no or reduced transmission or reception activity to active transmission or reception activity of a channel or a signal, or is used to trigger an SSB or SIB transmission. It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as Long-Term Evolution (LTE), LTE-Advanced, LTE-Advanced Pro, 5th Generation (5G), New Radio (NR), Internet-of-Things (IoT) and Narrow Band Internet of Things (NB-IoT), Industrial Internet of Things (IIoT), and 6th Generation (6G), the proposed concepts, schemes and any variation(s)/derivative(s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies. Thus, the scope of the present disclosure is not limited to the examples described herein. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of the present disclosure. The drawings illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. It is appreciable that the drawings are not necessarily in scale as some components may be shown to be out of proportion than the size in actual implementation in order to clearly illustrate the concept of the present disclosure. FIG. 1 is a diagram depicting an example scenario of determining whether to sleep under schemes in accordance with implementations of the present disclosure. FIG.