WO2025114995A1

WO2025114995A1 - Techniques for triggering wakeup of on-demand ssb transmission

Info

Publication number: WO2025114995A1
Application number: PCT/IB2025/050903
Authority: WO
Inventors: Karthikeyan Ganesan; Ravi Kuchibhotla
Original assignee: Lenovo Singapore Pte Ltd
Current assignee: Lenovo Singapore Pte Ltd
Priority date: 2024-01-26
Filing date: 2025-01-27
Publication date: 2025-06-05
Anticipated expiration: 2026-07-26

Abstract

Various aspects of the present disclosure relate to techniques for triggering wakeup of on-demand SSB transmissions. A UE (300) is configured to determine a mapping between a first set of resources and a second set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources, select at least one first resource of the first set of resources, to trigger at least one on-demand SSB transmission associated with an SCell, and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

Description

TECHNIQUES FOR TRIGGERING WAKEUP OF ON-DEMAND SSB

TRANSMISSION

TECHNICAL FIELD

[0001] The present disclosure relates to wireless communications, and more specifically to techniques for triggering wakeup of on-demand synchronization signal block (SSB) transmission.

BACKGROUND

[0002] A wireless communications system may include one or multiple network communication devices, such as base stations, which may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE), or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers, or the like). Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G)).

SUMMARY

[0003] An article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a,” “at least one,” “one or more,” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of’ or “one or more of’ or “one or both of’) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

[0004] Some implementations of the method and apparatuses described herein may determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources, select at least one first resource of the first set of resources, to trigger at least one on-demand SSB transmission associated with a secondary cell (SCell), based at least in part on the mapping, and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

[0005] Some implementations of the method and apparatuses described herein may transmit a set of spatial resources for triggering on-demand SSB transmission, receive a spatial resource transmission from a UE, the spatial resource transmission triggering on- demand SSB transmission, transmit an SSB in response to the received spatial resource transmission from the UE, and deactivate on-demand SSB transmission in response to not receiving a spatial resource transmission from the UE for a period of time.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 illustrates an example of a wireless communications system in accordance with aspects of the present disclosure.

[0007] Figure 2 illustrates a subset of SSB occasions, random access channel (RACH) resource configurations, and a mapping of SSB and RACH occasions for a target to trigger on-demand SSB in accordance with aspects of the present disclosure.

[0008] Figure 3 illustrates an example of a UE in accordance with aspects of the present disclosure.

[0009] Figure 4 illustrates an example of a processor in accordance with aspects of the present disclosure.

[0010] Figure 5 illustrates an example of a network equipment (NE) in accordance with aspects of the present disclosure. [0011] Figure 6 illustrates a flowcharts of method performed by an NE in accordance with aspects of the present disclosure.

[0012] Figure 7 illustrates a flowcharts of method performed by an NE in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0013] For network energy savings, procedures and signaling methods may support on-demand SSB SCell operation for UEs in connected mode configured with carrier aggregation (CA), for both intra- and inter-band CA. The procedures and signaling methods may specify triggering method(s) such as UE uplink wake-up-signal using an existing signal/channel, cell on/off indication via backhaul, SCell activation/deactivation signaling, or the like. In one embodiment, on-demand SSB transmission can be used by a UE for SCell time/frequency synchronization, L1/L3 measurements, and SCell activation, and is supported for FR1 and FR2 in non-shared spectrum.

[0014] In one embodiment, for network energy savings, procedures and signaling methods may support on-demand system information block 1 (SIB1) for UEs in idle/inactive mode, including triggering method by uplink wake-up-signal using an existing signal/channel, wake-up-signal configuration provisioning to UE, information exchange between gNBs at least for the configuration of wake-up signal (if necessary), and checkpoint for normative work.

[0015] In one embodiment, the on-demand SSB of an SCell can be triggered based on a wake-up signal from a UE so that the SCell can be turned on to boost the capacity, perform an emergency call, or the like.

[0016] In this disclosure, the mapping between the wake-up signal of a UE with that of the on-demand SSB occasions/set of SSB beams could be configured so that a portion of beams are activated to serve UEs in certain directions. Without such mapping, SSB of SCells may be transmitted in all the direction unnecessarily increasing the power consumption.

[0017] Solutions to the foregoing problems and limitations of existing solutions are described below with reference to the figures. Aspects of the present disclosure are described in the context of a wireless communications system. [0018] Figure 1 illustrates an example of a wireless communications system 100 in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more NE 102, one or more UE 104, and a core network (CN) 106. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a NR network, such as a 5G network, a 5G-Advanced (5G-A) network, or a 5G ultrawideband (5G-UWB) network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G, for example, 6G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA), etc.

[0019] The one or more NE 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the NE 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a network function, a network entity, a radio access network (RAN), a NodeB, an eNodeB (eNB), a next-generation NodeB (gNB), or other suitable terminology. An NE 102 and a UE 104 may communicate via a communication link, which may be a wireless or wired connection. For example, an NE 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

[0020] An NE 102 may provide a geographic coverage area for which the NE 102 may support services for one or more UEs 104 within the geographic coverage area. For example, an NE 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc.) according to one or multiple radio access technologies. In some implementations, an NE 102 may be moveable, for example, a satellite associated with a non-terrestrial network (NTN). In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas may be associated with different NE 102.

[0021] The one or more UE 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a remote unit, a mobile device, a wireless device, a remote device, a subscriber device, a transmitter device, a receiver device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Intemet-of-Things (loT) device, an Intemet-of-Everything (loE) device, or machine-type communication (MTC) device, among other examples.

[0022] A UE 104 may be able to support wireless communication directly with other UEs 104 over a communication link. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

[0023] An NE 102 may support communications with the CN 106, or with another NE 102, or both. For example, an NE 102 may interface with other NE 102 or the CN 106 through one or more backhaul links (e.g., SI, N2, N2, or network interface). In some implementations, the NE 102 may communicate with each other directly. In some other implementations, the NE 102 may communicate with each other or indirectly (e.g., via the CN 106. In some implementations, one or more NE 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC). An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or TRPs.

[0024] The CN 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The CN 106 may be an evolved packet core (EPC), or a 5G core (5GC), which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME), an access and mobility management functions (AMF)) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW), a Packet Data Network (PDN) gateway (P-GW), or a user plane function (UPF)). In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc.) for the one or more UEs 104 served by the one or more NE 102 associated with the CN 106.

[0025] The CN 106 may communicate with a packet data network over one or more backhaul links (e.g., via an SI, N2, N2, or another network interface). The packet data network may include an application server. In some implementations, one or more UEs 104 may communicate with the application server. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the CN 106 via an NE 102. The CN 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server using the established session (e.g., the established PDU session). The PDU session may be an example of a logical connection between the UE 104 and the CN 106 (e.g., one or more network functions of the CN 106).

[0026] In the wireless communications system 100, the NEs 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communications). In some implementations, the NEs 102 and the UEs 104 may support different resource structures. For example, the NEs 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the NEs 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the NEs 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures). The NEs 102 and the UEs 104 may support various frame structures based on one or more numerologies.

[0027] One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., jU=O) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., ^=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., ^=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., ^=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., ju=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., [1=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

[0028] A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames). Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

[0029] Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., /r=0, ju=l, ,11=2. [1=3, =4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols). In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing), a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., i=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots. [0030] In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz - 7.125 GHz), FR2 (24.25 GHz - 52.6 GHz), FR3 (7.125 GHz - 24.25 GHz), FR4 (52.6 GHz - 114.25 GHz), FR4a or FR4-1 (52.6 GHz - 71 GHz), and FR5 (114.25 GHz - 300 GHz). In some implementations, the NEs 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the NEs 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data). In some implementations, FR2 may be used by the NEs 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

[0031] FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies). For example, FR1 may be associated with a first numerology (e.g., =0). which includes 15 kHz subcarrier spacing; a second numerology (e.g., ^=1), which includes 30 kHz subcarrier spacing; and a third numerology (e.g., i=2), which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies). For example, FR2 may be associated with a third numerology (e.g., ^=2), which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., jtz=3), which includes 120 kHz subcarrier spacing.

[0032] In general, the subject matter disclosed herein is directed to triggering wakeup of on-demand SSB transmission. In conventional solutions, usually the mapping informs the UE about RACH resources for each SSB occasion so that the UE selects and transmits RACH according to the strongest SSB beam thereby establishing the SSB-RACH initial beam establishment. In one embodiment, the solutions discussed herein are directed to associating RACH resource/occasions to wake up on-demand SSB occasions, set of SSB beams, SSB beams transmission, or the like from SCells configured with NES. In one embodiment, the spatial relationship between the RACH resource and the SSB determines the directivity and duration of on-demand SSB transmission after receiving the wake up signal from the UE. [0033] The solutions described herein are equally applicable for both idle/inactive and connected mode UEs. In one embodiment, the idle/inactive UEs may need on- demand SSB as part of the cell selection/reselection mechanism while the connected mode UEs may trigger an on-demand SSB to perform radio resource management (RRM) measurement on SCells and/or activating the SCells.

[0034] A first embodiment is directed to associating uplink (UL) resources as a wake-up signal to trigger on demand SSB occasions, set of SSB beams, SSB beam, or the like from SCell. In such an embodiment, the UE may be provided with a set of UL resource via a primary cell (PCell) or target SCell to trigger on-demand SSB from a subset of SSB beams or SSB occasions from the target SCell.

[0035] In one embodiment, a PCell may provide a plurality of UL resources such as Scheduling Requests (SR) or Physical Random-Access Channel (PRACH) resource occasions e.g., time/frequency resources and dedicated contention free PRACH preambles mapped (e.g., one to one or one to many) to the plurality of SSB beams, a set of SSB beam, SSB occasions, or the like from an SCell configured with NES.

[0036] Figure 2 illustrates a subset of SSB occasions 202A-D, RACH resource configurations 204A-D, and A mapping 206 of SSB and RACH occasions for a target SCell to trigger on-demand SSB in accordance with aspects of the present disclosure. In one implementation, either PRACH or SR may be used as an UL resource. Although Figure 2 is shown with reference to PRACH, SR may also be equally applicable.

[0037] In one embodiment, a UE may select a PRACH resource for UL transmission from a plurality of RACH resource occasions. In one embodiment, each RACH resource may be spatially mapped to an SSB beam, a set of SSB beams, an SSB occasion, or the like of SCell to trigger an on-demand SSB from a subset of SSB beams/occasions. As used herein, spatial resource mapping may refer to how spatial resources, e.g., RACH spatial resources, are mapped to an SSB element, e.g., an SSB beam, a set of SSB beams, an SSB occasion, or the like.

[0038] In the case of multiple SCells, a first plurality of UL resources may be assigned to the plurality of SCells under consideration. In one embodiment, in each of those SCells, a plurality of UL resources may be spatially mapped to the plurality of SSB beams. In the case where one PRACH resource is assigned to a SCell, SSB beams are semi-statically configured for on-demand SSBs of that S SCell cell. [0039] In one implementation, SCells may be configured semi-statically by a set of SSB beams/occasions to be used for the on -demand SSB transmission and after the reception of the UL signaling from the UE.

[0040] In one embodiment, a UE may determine a spatial resource mapping, e.g., a RACH resource of an SCell for UL transmission, according to the Direction of Arrival (DoA) estimation from downlink transmission from PCell, considering the overlaid PCell and SCell carriers from the same node. In another implementation, there may be an overlaid spatial filter configuration between the PCell and SCell. When the wake up signal is received by a spatial Rx filter by PCell, then the PCell may wake up a corresponding transmission spatial filter of an SSB beam or a set of SSB beams that are signaled via an exchange between the PCell and the SCell.

[0041] In one embodiment, a quasi co-location (QCL) type e.g., qcl-typeD provides a spatial relationship mapping between a source reference signal (RS) and a target RS. This means that a single source to single target beam association can be established. The quasi co-location relationship is configured by the higher layer parameter qcl-Type 1 for the first DL RS, and qcl-Type2 for the second DL RS (if configured). For the case of two DL RSs, the QCL types shall not be the same, regardless of whether the references are to the same DL RS or different DL RSs. The quasi co-location types corresponding to each DL RS are given by the higher layer parameter qcl-Type in QCL-Info and may take one of the following values:

- 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

- 'QCL-TypeB': {Doppler shift, Doppler spread}

- 'QCL-TypeC: {Doppler shift, average delay}

- 'QCL-TypeD': {Spatial Rx parameter}

[0042] As used herein, a “UE panel” may be a logical entity with physical UE antennas mapped to the logical entity. How to map physical UE antennas to the logical entity may be up to UE implementation. Depending on UE’s own implementation, a “UE panel” can have at least one of the following functionalities as an operational role of Unit of antenna group to control its Tx beam independently, Unit of antenna group to control its transmission power independently, Unit of antenna group to control its transmission timing independently. The “UE panel” may be transparent to gNB/peer UE(s). For certain condition} s), gNB or network or peer UE can assume the mapping between UE’s physical antennas to the logical entity “UE panel” may not be changed. For example, the condition may include until the next update or report from UE or comprise a duration of time over which the gNB or UE assumes there will be no change to the mapping. The UE may report its UE capability with respect to the “UE panel” to the gNB or network or peer UE. The UE capability may include at least the number of “UE panels”. In one implementation, the UE may support UL or SL transmission from one beam within a panel; with multiple panels, more than one beam (one beam per panel) may be used for UL. In another implementation, more than one beam per panel may be supported/used for UL.

[0043] In one embodiment, a gNB’s SCell, after receiving the RACH from a spatial direction that is mapped to a spatial SSB using QCL-D type or a set of SSB beams or occasions, may prepare for the transmission of the SSB. There may be a minimum time gap in terms of a number of slots or milliseconds between the reception of RACH from the UE and transmission of SSB from the SCell, which may be configured at the UE according to the subcarrier spacing of the SCell, so that the UE may start monitoring the SSB occasion from the SCell after the RACH transmission. If the UE does not receive SSB within a configured time window where the UE monitors for SSB occasions, the UE may start transmission of RACH again with a higher power level. Such a power ramp up may be configured in step size. In one implementation, UE may start a timer after the transmission of RACH and when there is no SSB transmission from SCell when the timer expires then the UE may start RACH transmission with higher transmit power using the power ramping up in step. The timer stops when the UE receives SSB before the expiry of the timer.

[0044] In one embodiment, on-demand SSB transmission of an SCell from an SSB beam or set of SSB beams or occasions may be deactivated after a period of inactivity. When the gNB’s SCell does not receive any legacy RACH transmission spatially mapped to an SSB beam or a set of SSB beams or occasions from a UE for a period of time, then on-demand SSB transmission from that SSB beam or set of SSB beams or occasions may be deactivated.

[0045] A second embodiment is directed to activation of SCell using a wake-up signal. In one embodiment, the wake up signaling transmission by the UE, such as PRACH or SR configuration per SCell via PCell, may also activate the SCell and then an on-demand SSB may be transmited by that SCell after the activation to perform the RRM measurement.

[0046] A third embodiment is directed to on-demand SIB 1 triggering for idle/inactive mode UEs. In one embodiment, a UE in an idle mode may measure the SSB of the NES cell and while trying to evaluate the cell for cell selection or cell reselection may need to transmit a wake up signal to trigger on-demand SIB 1 from that target cell. The UE may be configured with a plurality of wake up signals mapped to the plurality of NES cells where each wake up signal configuration may be mapped to one NES cell. Such configuration may be provided by a low power wake signaling to the low power wake up radio. In another implementation, paging signaling or early paging signaling may provide such configuration to the UE. The wakeup signaling for triggering on-demand SIB1 may follow same procedure as that of on-demand SSB as explained in the above embodiments.

[0047] Figure 3 illustrates an example of a UE 300 in accordance with aspects of the present disclosure. The UE 300 may include a processor 302, a memory 304, a controller 306, and a transceiver 308. The processor 302, the memory 304, the controller 306, or the transceiver 308, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

[0048] The processor 302, the memory 304, the controller 306, or the transceiver 308, or various combinations or components thereof may be implemented in hardware (e.g., circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

[0049] The processor 302 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof). In some implementations, the processor 302 may be configured to operate the memory 304. In some other implementations, the memory 304 may be integrated into the processor 302. The processor 302 may be configured to execute computer-readable instructions stored in the memory 304 to cause the UE 300 to perform various functions of the present disclosure.

[0050] The memory 304 may include volatile or non-volatile memory. The memory 304 may store computer-readable, computer-executable code including instructions when executed by the processor 302 cause the UE 300 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 304 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

[0051] In some implementations, the processor 302 and the memory 304 coupled with the processor 302 may be configured to cause the UE 300 to perform one or more of the functions described herein (e.g., executing, by the processor 302, instructions stored in the memory 304). For example, the processor 302 may support wireless communication at the UE 300 in accordance with examples as disclosed herein.

[0052] The UE 300 may be configured to support a means to determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources, select at least one first resource of the first set of resources, to trigger at least one on-demand SSB transmission associated with an SCell, based at least in part on the mapping, and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

[0053] In one embodiment, one or more of the first set of resources or the second set of resources comprises one or more RACH resources or one or more SR resources. In one embodiment, the UE 300 may be configured to support a means to receive, from a PCell associated with the SCell, an allocation of the first set of resources, wherein the first set of resources comprises a set of RACH resources including the one or more RACH resource. [0054] In one embodiment, one or more of the first set of resources or the second set of resources comprises one or more of a set of RACH resources, a set of SSB beams, or a set of SSB occasions, and wherein the mapping is indicative of the spatial relationship between the set of RACH resources and the set of SSB beams or the set of SSB occasions.

[0055] In one embodiment, the at least one uplink transmission comprises at least one RACH transmission, and wherein the at least one first resource comprises at least one RACH resource. In one embodiment, the UE 300 may be configured to support a means to select the at least one first resource based at least in part on an estimated DOA associated with at least one downlink transmission from a PCell associated with the SCell.

[0056] In one embodiment, the UE 300 may be configured to support a means to receive the at least one on-demand SSB transmission associated with the SCell using at least one second resource of the second set of resource, wherein a minimum time gap exists between the at least one uplink transmission and the at least one on-demand SSB transmission. In one embodiment, the minimum time gap is based on a subcarrier spacing associated with the SCell.

[0057] In one embodiment, the UE 300 may be configured to support a means to retransmit the at least one uplink transmission using the at least one first resource of the first set of resources and with an increased power level based at least in part on increasing a power level by a step size.

[0058] In one embodiment, the UE 300 may be configured to support a means to transmit a wake-up signal to trigger the at least one on-demand SSB transmission associated with the Scell. In one embodiment, the wake-up signal triggers at least one on-demand SIB 1 transmission associated with the SCell and in response to the UE being in an idle mode.

[0059] The controller 306 may manage input and output signals for the UE 300. The controller 306 may also manage peripherals not integrated into the UE 300. In some implementations, the controller 306 may utilize an operating system such as iOS®, ANDROID®, WINDOWS®, or other operating systems. In some implementations, the controller 306 may be implemented as part of the processor 302. [0060] In some implementations, the UE 300 may include at least one transceiver 308. In some other implementations, the UE 300 may have more than one transceiver 308. The transceiver 308 may represent a wireless transceiver. The transceiver 308 may include one or more receiver chains 310, one or more transmitter chains 312, or a combination thereof.

[0061] A receiver chain 310 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 310 may include one or more antennas for receiving the signal over the air or wireless medium. The receiver chain 310 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. The receiver chain 310 may include at least one demodulator configured to demodulate the received signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 310 may include at least one decoder for decoding and processing the demodulated signal to receive the transmitted data.

[0062] A transmitter chain 312 may be configured to generate and transmit signals (e.g., control information, data, packets). The transmitter chain 312 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM). The transmitter chain 312 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 312 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

[0063] Figure 4 illustrates an example of a processor 400 in accordance with aspects of the present disclosure. The processor 400 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 400 may include a controller 402 configured to perform various operations in accordance with examples as described herein. The processor 400 may optionally include at least one memory 404, which may be, for example, an L1/L2/L3 cache. Additionally, or alternatively, the processor 400 may optionally include one or more arithmetic -logic units (ALUs) 406. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses).

[0064] The processor 400 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 400) or other memory (e.g., random access memory (RAM), read-only memory (ROM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), static RAM (SRAM), ferroelectric RAM (FeRAM), magnetic RAM (MRAM), resistive RAM (RRAM), flash memory, phase change memory (PCM), and others).

[0065] The controller 402 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 400 to cause the processor 400 to support various operations in accordance with examples as described herein. For example, the controller 402 may operate as a control unit of the processor 400, generating control signals that manage the operation of various components of the processor 400. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

[0066] The controller 402 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 404 and determine subsequent instruction(s) to be executed to cause the processor 400 to support various operations in accordance with examples as described herein. The controller 402 may be configured to track memory address of instructions associated with the memory 404. The controller 402 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 402 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 400 to cause the processor 400 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 402 may be configured to manage flow of data within the processor 400. The controller 402 may be configured to control transfer of data between registers, arithmetic logic units (ALUs), and other functional units of the processor 400.

[0067] The memory 404 may include one or more caches (e.g., memory local to or included in the processor 400 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementations, the memory 404 may reside within or on a processor chipset (e.g., local to the processor 400). In some other implementations, the memory 404 may reside external to the processor chipset (e.g., remote to the processor 400).

[0068] The memory 404 may store computer-readable, computer-executable code including instructions that, when executed by the processor 400, cause the processor 400 to perform various functions described herein. The code may be stored in a non- transitory computer-readable medium such as system memory or another type of memory. The controller 402 and/or the processor 400 may be configured to execute computer-readable instructions stored in the memory 404 to cause the processor 400 to perform various functions. For example, the processor 400 and/or the controller 402 may be coupled with or to the memory 404, the processor 400, the controller 402, and the memory 404 may be configured to perform various functions described herein. In some examples, the processor 400 may include multiple processors and the memory 404 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

[0069] The one or more ALUs 406 may be configured to support various operations in accordance with examples as described herein. In some implementations, the one or more ALUs 406 may reside within or on a processor chipset (e.g., the processor 400). In some other implementations, the one or more ALUs 406 may reside external to the processor chipset (e.g., the processor 400). One or more ALUs 406 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 406 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 406 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 406 may support logical operations such as AND, OR, exclusive-OR (XOR), not-OR (NOR), and not-AND (NAND), enabling the one or more ALUs 406 to handle conditional operations, comparisons, and bitwise operations.

[0070] The processor 400 may support wireless communication in accordance with examples as disclosed herein. The processor 400 may be configured to or operable to support a means to determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources, select at least one first resource of the first set of resources, to trigger at least one on-demand SSB transmission associated with an SCell, based at least in part on the mapping, and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

[0071] In one embodiment, one or more of the first set of resources or the second set of resources comprises one or more RACH resources or one or more SR resources. In one embodiment, the processor 400 may be configured to or operable to support a means to receive, from a PCell associated with the SCell, an allocation of the first set of resources, wherein the first set of resources comprises a set of RACH resources including the one or more RACH resource.

[0072] In one embodiment, one or more of the first set of resources or the second set of resources comprises one or more of a set of RACH resources, a set of SSB beams, or a set of SSB occasions, and wherein the mapping is indicative of the spatial relationship between the set of RACH resources and the set of SSB beams or the set of SSB occasions.

[0073] In one embodiment, the at least one uplink transmission comprises at least one RACH transmission, and wherein the at least one first resource comprises at least one RACH resource. In one embodiment, the processor 400 may be configured to or operable to support a means to select the at least one first resource based at least in part on an estimated DOA associated with at least one downlink transmission from a PCell associated with the SCell. [0074] In one embodiment, the processor 400 may be configured to or operable to support a means to receive the at least one on-demand SSB transmission associated with the SCell using at least one second resource of the second set of resource, wherein a minimum time gap exists between the at least one uplink transmission and the at least one on-demand SSB transmission. In one embodiment, the minimum time gap is based on a subcarrier spacing associated with the SCell.

[0075] In one embodiment, the processor 400 may be configured to or operable to support a means to retransmit the at least one uplink transmission using the at least one first resource of the first set of resources and with an increased power level based at least in part on increasing a power level by a step size.

[0076] In one embodiment, the processor 400 may be configured to or operable to support a means to transmit a wake-up signal to trigger the at least one on-demand SSB transmission associated with the Scell. In one embodiment, the wake-up signal triggers at least one on -demand SIB1 transmission associated with the SCell and in response to the UE being in an idle mode.

[0077] Figure 5 illustrates an example of a NE 500 in accordance with aspects of the present disclosure. The NE 500 may include a processor 502, a memory 504, a controller 506, and a transceiver 508. The processor 502, the memory 504, the controller 506, or the transceiver 508, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

[0078] The processor 502, the memory 504, the controller 506, or the transceiver 508, or various combinations or components thereof may be implemented in hardware (e.g., circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

[0079] The NE 500 may be configured to support a means to transmit a set of spatial resources for triggering on-demand SSB transmission, receive a spatial resource transmission from a UE, the spatial resource transmission triggering on-demand SSB transmission, transmit an SSB in response to the received spatial resource transmission from the UE, and deactivate on -demand SSB transmission in response to not receiving a spatial resource transmission from the UE for a period of time.

[0080] In one embodiment, the NE 500 may be configured to support a means to deactivate the at least one on-demand SSB transmission associated with the SCell based at least in part on an inactivity timer associated with the SCell. In one embodiment, the NE 500 may be configured to support a means to deactivate the at least one on-demand SSB transmission in response to not receiving a legacy RACH transmission spatially mapped to an SSB transmission from a UE for a period of time.

[0081] The processor 502 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof). In some implementations, the processor 502 may be configured to operate the memory 504. In some other implementations, the memory 504 may be integrated into the processor 502. The processor 502 may be configured to execute computer-readable instructions stored in the memory 504 to cause the NE 500 to perform various functions of the present disclosure.

[0082] The memory 504 may include volatile or non-volatile memory. The memory 504 may store computer-readable, computer-executable code including instructions when executed by the processor 502 causes the NE 500 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 504 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

[0083] In some implementations, the processor 502 and the memory 504 coupled with the processor 502 may be configured to cause the NE 500 to perform one or more of the functions described herein (e.g., executing, by the processor 502, instructions stored in the memory 504). For example, the processor 502 may support wireless communication at the NE 500 in accordance with examples as disclosed herein.

[0084] The controller 506 may manage input and output signals for the NE 500. The controller 506 may also manage peripherals not integrated into the NE 500. In some implementations, the controller 506 may utilize an operating system such as iOS®, ANDROID®, WINDOWS®, or other operating systems. In some implementations, the controller 506 may be implemented as part of the processor 502.

[0085] In some implementations, the NE 500 may include at least one transceiver 508. In some other implementations, the NE 500 may have more than one transceiver 508. The transceiver 508 may represent a wireless transceiver. The transceiver 508 may include one or more receiver chains 510, one or more transmitter chains 512, or a combination thereof.

[0086] A receiver chain 510 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 510 may include one or more antennas for receiving the signal over the air or wireless medium. The receiver chain 510 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. The receiver chain 510 may include at least one demodulator configured to demodulate the received signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 510 may include at least one decoder for decoding and processing the demodulated signal to receive the transmitted data.

[0087] A transmitter chain 512 may be configured to generate and transmit signals (e.g., control information, data, packets). The transmitter chain 512 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM). The transmitter chain 512 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 512 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

[0088] Figure 6 illustrates a flowchart 600 of a method in accordance with aspects of the present disclosure. The operations of the method may be implemented by a UE as described herein. In some implementations, the UE may execute a set of instructions to control the function elements of the UE to perform the described functions. [0089] At 602, the method may determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources. The operations of 602 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 602 may be performed by a UE as described with reference to Figure 3.

[0090] At 604, the method may select at least one first resource of the first set of resources, to trigger at least one on-demand SSB transmission associated with a SCell, based at least in part on the mapping. The operations of 604 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 604 may be performed by a UE as described with reference to Figure 3.

[0091] At 606, the method may perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell. The operations of 606 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 606 may be performed by a UE as described with reference to Figure 3.

[0092] Figure 7 illustrates a flowchart 700 of a method in accordance with aspects of the present disclosure. The operations of the method may be implemented by an NE as described herein. In some implementations, the NE may execute a set of instructions to control the function elements of the NE to perform the described functions.

[0093] At 702, the method may transmit a set of spatial resources for triggering on- demand SSB transmission. The operations of 702 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 702 may be performed by an NE as described with reference to Figure 5.

[0094] At 704, the method may receive a spatial resource transmission from a UE, the spatial resource transmission triggering on-demand SSB transmission. The operations of 704 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 704 may be performed by an NE as described with reference to Figure 5. [0095] At 706, the method may transmit an SSB in response to the received spatial resource transmission from the UE. The operations of 706 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 706 may be performed by an NE as described with reference to Figure 5.

[0096] At 708, the method may deactivate on-demand SSB transmission in response to not receiving a spatial resource transmission from the UE for a period of time. The operations of 708 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 708 may be performed by an NE as described with reference to Figure 5.

[0097] It should be noted that the method described herein describes A possible implementation, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible.

[0098] The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

CLAIMS What is claimed is:

1 . A user equipment (UE) for wireless communication, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the UE to: determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources; select at least one first resource of the first set of resources, to trigger at least one on-demand synchronization signal block (SSB) transmission associated with a secondary cell (SCell), based at least in part on the mapping; and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

2. The UE of claim 1, wherein one or more of the first set of resources or the second set of resources comprises one or more random access channel (RACH) resources or one or more scheduling request (SR) resources.

3. The UE of claim 2, wherein the at least one processor is configured to cause the UE to receive, from a primary cell (PCell) associated with the SCell, an allocation of the first set of resources, wherein the first set of resources comprises a set of random access channel (RACH) resources including the one or more RACH resources.

4. The UE of claim 2, wherein one or more of the first set of resources or the second set of resources comprises one or more of a set of random access channel (RACH) resources, a set of SSB beams, or a set of SSB occasions, and wherein the mapping is indicative of the spatial relationship between the set of RACH resources and the set of SSB beams or the set of SSB occasions.

5. The UE of claim 1, wherein the at least one uplink transmission comprises at least one random access channel (RACH) transmission, and wherein the at least one first resource comprises at least one RACH resource.

6. The UE of claim 1, wherein the at least one processor is configured to cause the UE to select the at least one first resource based at least in part on an estimated direction of arrival (DOA) associated with at least one downlink transmission from a primary cell (PCell) associated with the SCell.

7. The UE of claim 1, wherein the at least one processor is configured to cause the UE to: receive the at least one on-demand SSB transmission associated with the SCell using at least one second resource of the second set of resources, wherein a minimum time gap exists between the at least one uplink transmission and the at least one on-demand SSB transmission.

8. The UE of claim 7, wherein the minimum time gap is based on a subcarrier spacing associated with the SCell.

9. The UE of claim 7, wherein the at least one processor is configured to cause the UE to retransmit the at least one uplink transmission using the at least one first resource of the first set of resources and with an increased power level based at least in part on increasing a power level by a step size.

10. The UE of claim 1, wherein the at least one processor is configured to cause the UE to transmit a wake-up signal to trigger the at least one on-demand SSB transmission associated with the SCell.

11. The UE of claim 10, wherein the wake-up signal triggers at least one on -demand system information block 1 (SIB1) transmission associated with the SCell and in response to the UE being in an idle mode.

12. A processor for wireless communication, comprising: at least one controller coupled with at least one memory and configured to cause the processor to: determine a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources; select at least one first resource of the first set of resources, to trigger at least one on-demand synchronization signal block (SSB) transmission associated with a secondary cell (SCell), based at least in part on the mapping; and perform at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

13. The processor of claim 12, wherein one or more of the first set of resources or the second set of resources comprises one or more random access channel (RACH) resources or one or more scheduling request (SR) resources.

14. The processor of claim 13, wherein the at least one controller is configured to cause the processor to receive, from a primary cell (PCell) associated with the SCell, an allocation of the first set of resources, wherein the first set of resources comprises a set of random access channel (RACH) resources including the one or more RACH resources.

15. The processor of claim 13, wherein one or more of the first set of resources or the second set of resources comprises one or more of a set of random access channel (RACH) resources, a set of SSB beams, or a set of SSB occasions, and wherein the mapping is indicative of the spatial relationship between the set of RACH resources and the set of SSB beams or the set of SSB occasions.

16. The processor of claim 12, wherein the at least one uplink transmission comprises at least one random access channel (RACH) transmission, and wherein the at least one first resource comprises at least one RACH resource.

17. A method performed by a user equipment (UE), the method comprising: determining a mapping between a first set of resources and a second set of resources different than the first set of resources, wherein the mapping is indicative of a spatial relationship between the first set of resources and the second set of resources; selecting at least one first resource of the first set of resources, to trigger at least one on-demand synchronization signal block (SSB) transmission associated with a secondary cell (SCell), based at least in part on the mapping; and performing at least one uplink transmission using the at least one first resource of the first set of resources, wherein the at least one uplink transmission triggers the at least one on-demand SSB associated with the SCell.

18. A network equipment (NE) for wireless communication, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the NE to: transmit a set of spatial resources for triggering on-demand synchronization signal block (SSB) transmission; receive a spatial resource transmission from a user equipment (UE), the spatial resource transmission triggering on- demand SSB transmission; transmit an SSB in response to the received spatial resource transmission from the UE; and deactivate on-demand SSB transmission in response to not receiving a spatial resource transmission from the UE for a period of time.

19. The NE of claim 18, wherein the at least one processor is configured to deactivate the on-demand SSB transmission associated with an SCell based at least in part on an inactivity timer associated with the SCell.

20. The NE of claim 19, wherein the at least one processor is configured to deactivate the on-demand SSB transmission in response to not receiving a legacy random access channel (RACH) transmission spatially mapped to an SSB transmission from a UE for a period of time.