PRACH resource adaptation

Abstract

Various aspects of the present disclosure relate to adaptations to PRACH resources. In one aspect, user equipment receives from a base station one of a PDCCH command, paging signaling, or a DCI for scheduling SIB1, SIB1 configures a set of ROs, and one of the PDCCH command, paging signaling, or a DCI for scheduling SIB1 configures or activates at least one additional RO. The UE performs a RACH procedure based on at least one additional RO.

Description

Technology Field

[0001] The present disclosure relates to user equipment (UE), a base station, processors for wireless communication, and methods for adapting physical random access channel (PRACH) resources. Background Technology

[0002] A wireless communication system may include one or more network communication devices, such as base stations, which may be otherwise known by other appropriate terms, such as eNodeBs (eNBs), next-generation NodeBs (gNBs), or other appropriate terms. Each network communication device, such as a base station, may support wireless communication with one or more user communication devices, such as user equipment (UEs) or other appropriate terms. A wireless communication system may support wireless communication with one or more user communication devices by utilizing the resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, etc.) or frequency resources (e.g., subcarriers, carriers)). Additionally, a wireless communication system may support wireless communication through various radio access technologies, including 3G (third generation) radio access technology, 4G (fourth generation) radio access technology, and 5G (fifth generation) radio access technology, among other appropriate radio access technologies beyond 5G (e.g., 6th generation (6G)).

[0003] In 5G new radio (NR) systems, random access procedures are utilized for various purposes. For example, random access procedures may be used by a UE to find a cell to camp on during initial access; or by a radio resource control (RRC) idle / inactive UE to switch to RRC access mode to begin data transmission / reception; or by an RRC access UE to re-establish uplink (UL) synchronization. Improvements are still needed regarding random access procedures, particularly regarding technologies related to the adaptation of PRACH resources.

[0004] The present disclosure relates to methods, devices, and systems that support PRACH resource adaptation. By dynamically configuring or enabling at least one additional Random Access Channel (RACH) Opportunity (RO), the RACH procedure can be performed on additional PRACH resources in addition to the PRACH resources configured by SIB1. In this way, the latency of the RACH procedure can be reduced, particularly for low-load scenarios where sparse PRACH resources are configured for network energy conservation.

[0005] In a first aspect of the solution, the UE receives from a base station one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling system information block 1 (SIB1), and SIB1 configures a set of random access channel (RACH) opportunities (ROs), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 configures or activates at least one additional RO. The UE performs a RACH procedure based on at least one additional RO. In this way, PRACH resources can be dynamically adapted, and a RACH procedure can be performed on additional PRACH resources in addition to the PRACH resources configured by SIB1. Thus, the latency of the RACH procedure can be reduced without significantly increasing power consumption on the network side.

[0006] In some implementations of the methods and apparatus described herein, at least one additional RO may include one additional RO, the additional RO is configured or enabled by a PDCCH command, and the additional RO is associated with a synchronization signal and a physical broadcast channel (PBCH) block (SSB) indicated in the PDCCH command.

[0007] In some implementations of the methods and apparatus described herein, the PDCCH command may include resource configurations for additional ROs.

[0008] Some implementations of the methods and apparatus described herein may further include receiving resource configurations for additional ROs from a base station. The resource configurations are carried in a medium access control (MAC) control element (CE) signaling or a radio resource control (RRC) signaling. The PDCCH command may include an indication to enable additional ROs.

[0009] In some implementations of the methods and apparatus described herein, the additional RO is a first additional RO, and performing the RACH procedure may include transmitting a preamble to a base station on the first additional RO—the time offset between the PDCCH command and the first slot having the first additional RO is configured or predefined by the base station—and monitoring a random access response (RAR) message indicating reception of the preamble in a RAR window.

[0010] Some implementations of the methods and apparatus described herein may further include performing a second RACH procedure based on a second additional RO when a RAR message is not received in the RAR window. The time offset between the end of the RAR window and the second slot having the second additional RO is configured or predefined by the base station.

[0011] In some implementations of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and the set of additional ROs is configured or enabled by paging signaling, and the paging signaling is one of a paging message; a paging DCI for scheduling a paging message; or a paging early indication (PEI) indicating the presence of a paging message.

[0012] Some implementations of the methods and devices described herein may further include transmitting to a network device an indication of the ability to support physical RACH (PRACH) resource adaptation triggered by paging signaling.

[0013] In some implementations of the methods and apparatus described herein, paging signaling may include resource configurations for a set of additional ROs.

[0014] Some implementations of the methods and apparatus described herein may further include receiving SIB1 from a base station, and SIB1 may include resource configurations for an additional set of ROs. Paging signaling may include an indication to activate an additional set of ROs.

[0015] Some implementations of the methods and apparatus described herein may further include receiving SIB1 from a base station, SIB1 may include resource configurations for at least one set of additional ROs, and at least one set of additional ROs may include a set of additional ROs. Paging signaling may include an indication of a set of additional ROs, and the set of additional ROs is activated by the paging signaling.

[0016] In some implementations of the methods and apparatus described herein, the time offset between the last monitoring opportunity for the paging DCI and the first slot having a set of additional ROs is configured or predefined by the base station.

[0017] In some implementations of the methods and devices described herein, the time offset between the last slot having a paging message and the first slot having an additional set of ROs is configured or predefined by the base station.

[0018] In some implementations of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and the set of additional ROs is enabled by a DCI for scheduling SIB1, and the DCI for scheduling SIB1 may include an indication of the availability of the set of additional ROs. SIB1 may include resource configurations for the set of additional ROs.

[0019] In some implementations of the methods and apparatus described herein, the time offset between the last slot having a DCI for scheduling SIB1 and the first slot having a set of additional ROs is configured or predefined by the base station.

[0020] In some implementations of the methods and apparatus described herein, the time offset between the last slot having SIB1 and the first slot having an additional set of ROs is configured or predefined by the base station.

[0021] In some implementations of the methods and apparatus described herein, at least one additional RO is available in a time window. The time window is configured or predefined by a base station.

[0022] Some implementations of the methods and apparatus described herein may further include receiving SIB1 from a base station; determining a set of ROs based on SIB1; and performing a unified SSB-to-RO association for the set of ROs and at least one additional RO.

[0023] In some embodiments of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and performing an integrated SSB-to-RO association may include performing a first SSB-to-RO association on a set of ROs; and determining a second SSB-to-RO association on a set of additional ROs based on the first SSB-to-RO association.

[0024] In some implementations of the methods and apparatus described herein, determining the second SSB-to-RO association may include causing the second SSB-to-RO association to follow the first SSB-to-RO association in a sequential and wrap-round manner.

[0025] In some implementations of the methods and apparatuses described herein, determining a second SSB-to-RO association may further include determining one or more of a set of additional ROs as invalid. At least one of the one or more additional ROs and a set of ROs following the one or more additional ROs cannot form an SSB-to-RO mapping cycle.

[0026] Some implementations of the methods and apparatus described herein may further include determining to invalidate at least one additional RO. The additional RO overlaps with one of the sets of ROs.

[0027] In a second aspect of the solution, the base station transmits to the UE one of a Physical Downlink Control Channel (PDCCH) command, paging signaling, or Downlink Control Information (DCI) for scheduling System Information Block 1 (SIB1), and SIB1 configures a set of Random Access Channel (RACH) Opportunities (ROs), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 configures or activates at least one additional RO. The base station monitors a preamble on at least one additional RO. In this way, the base station can dynamically configure or activate additional PRACH resources. Thus, the latency of the RACH procedure can be reduced without significantly increasing power consumption on the network side.

[0028] In some implementations of the methods and apparatus described herein, at least one additional RO may include one additional RO, the additional RO is configured or enabled by a PDCCH command, and the additional RO is associated with a synchronization signal and a PBCH block (SSB) indicated in the PDCCH command.

[0029] In some implementations of the methods and apparatus described herein, the PDCCH command may include resource configurations for additional ROs.

[0030] Some implementations of the methods and apparatus described herein may further include transmitting to the UE an indication of resource configurations for additional ROs, and the resource configurations are carried in Media Access Control (MAC) Control Element (CE) signaling or Radio Resource Control (RRC) signaling. The PDCCH command may include an indication to enable additional ROs.

[0031] In some implementations of the methods and apparatus described herein, the additional RO is a first additional RO, and the time offset between the PDCCH command and the first slot having the first additional RO is predefined or associated with the configuration from the base station to the UE. Some implementations of the methods and apparatus described herein may further include transmitting a Random Access Response (RAR) message indicating the reception of the preamble in a RAR window when the preamble is received on the additional RO.

[0032] Some implementations of the methods and apparatus described herein may further include monitoring a preamble on a second additional RO if the preamble is not received on the additional RO. The time offset between the end of the RAR window and the second slot having the second additional RO is predefined or associated with the configuration from the base station to the UE.

[0033] In some implementations of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and the set of additional ROs is configured or enabled by paging signaling, and the paging signaling is one of a paging message; a paging DCI for scheduling a paging message; or a paging early indication (PEI) indicating the presence of a paging message.

[0034] Some implementations of the methods and devices described herein may further include receiving from a network device an indication of a UE’s ability to support physical RACH (PRACH) resource adaptation triggered by paging signaling.

[0035] In some implementations of the methods and apparatus described herein, paging signaling may include resource configurations for a set of additional ROs.

[0036] Some implementations of the methods and apparatus described herein may further include transmitting SIB1 to a UE, and SIB1 may include resource configurations for an additional set of ROs. Paging signaling may include an indication to activate an additional set of ROs.

[0037] Some implementations of the methods and apparatus described herein may further include transmitting SIB1 to a UE, SIB1 may include resource configurations for at least one set of additional ROs, and at least one set of additional ROs may include a set of additional ROs. Paging signaling may include an indication of a set of additional ROs, and the set of additional ROs is activated by the paging signaling.

[0038] In some implementations of the methods and apparatus described herein, the time offset between the last monitoring opportunity for the paging DCI and the first slot having a set of additional ROs is predefined or associated with the configuration from the base station to the UE.

[0039] In some implementations of the methods and apparatus described herein, the time offset between the last slot having a paging message and the first slot having an additional set of ROs is predefined or associated with the configuration from the base station to the UE.

[0040] In some implementations of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and the set of additional ROs is enabled by a DCI for scheduling SIB1, and the DCI for scheduling SIB1 may include an indication of the availability of the set of additional ROs. SIB1 may include resource configurations for the set of additional ROs.

[0041] In some implementations of the methods and apparatus described herein, the time offset between the last slot having a DCI for scheduling SIB1 and the first slot having a set of additional ROs is predefined or associated with the configuration from the base station to the UE.

[0042] In some implementations of the methods and apparatus described herein, the time offset between the last slot having SIB1 and the first slot having an additional set of ROs is predefined or associated with the configuration from the base station to the UE.

[0043] In some implementations of the methods and apparatus described herein, at least one additional RO is available in a time window, and the time window is predefined or associated with the configuration from the base station to the UE.

[0044] Some implementations of the methods and apparatus described herein may further include transmitting SIB1 to the UE, and

[0045] An integrated SSB-to-RO association is formed for a set of ROs and at least one additional RO.

[0046] In some embodiments of the methods and apparatus described herein, at least one additional RO may include a set of additional ROs, and the integrated SSB-to-RO association may include a first SSB-to-RO association for a set of ROs and a second SSB-to-RO association for a set of additional ROs, and the second SSB-to-RO association is based on the first SSB-to-RO association.

[0047] In some implementations of the methods and apparatuses described herein, the second SSB-to-RO association follows the first SSB-to-RO association in a sequential and wrap-round manner.

[0048] In some implementations of the methods and apparatuses described herein, one or more of the sets of additional ROs are invalid, and at least one of the sets of ROs following one or more additional ROs cannot form an SSB-to-RO mapping cycle.

[0049] In some implementations of the methods and apparatus described herein, at least one of the additional ROs is invalid, and the additional RO overlaps with one of the sets of ROs.

[0050] In a third aspect of the solution, a device for performing an access and mobility management function (AMF) receives from a UE an indication of the UE's ability to support physical random access channel (PRACH) resource adaptation triggered by paging signaling; and transmits to a base station an indication of the UE's ability to support PRACH resource adaptation triggered by paging signaling. In this way, the base station can identify UEs that support additional PRACH resource allocation. As a result, the base station can dynamically trigger PRACH resource adaptation when paging a UE, and thus reduce the latency of the RACH procedure.

[0051] In some implementations of the methods and apparatus described herein, paging signaling is one of a paging message; paging downlink control information (DCI) for scheduling a paging message; or a paging early indication (PEI) indicating the presence of a paging message. Brief explanation of the drawing

[0052] FIG. 1a illustrates an example of a wireless communication system that supports PRACH resource adaptation according to aspects of the present disclosure. FIG. 1b illustrates an example of an NR 4-step random access procedure that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. FIG. 1c illustrates an example of an NR random access procedure that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. FIG. 2 illustrates an exemplary signaling chart of a communication process that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. FIG. 3 illustrates an example of adapting a PRACH resource by a PDCCH command according to some exemplary embodiments of the present disclosure. FIG. 4 illustrates an exemplary signaling chart of a communication process that supports PRACH resource adaptation by paging signaling according to some exemplary embodiments of the present disclosure. FIG. 5 illustrates an example of PRACH resource adaptation by paging signaling according to some exemplary embodiments of the present disclosure. FIG. 6 illustrates an example of an SSB-to-RO association according to some exemplary embodiments of the present disclosure. FIG. 7 illustrates another example of an SSB-to-RO association according to some exemplary embodiments of the present disclosure. FIG. 8 illustrates an example of a device that supports PRACH resource adaptation according to embodiments of the present disclosure. FIG. 9 illustrates examples of processors that support PRACH resource adaptation according to embodiments of the present disclosure. FIGS. 10 to 12 illustrate flowcharts of methods supporting PRACH resource adaptation according to embodiments of the present disclosure. Throughout the drawings, identical or similar reference numbers represent identical or similar elements. Specific details for implementing the invention

[0053] The principles of the present disclosure will now be described with reference to some embodiments. It should be understood that these embodiments are described for illustrative purposes only and do not imply any limitation to the scope of the present disclosure, but are intended to help a person skilled in the art understand and implement the present disclosure. The disclosures described herein may be implemented in various ways other than those described below.

[0054] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as generally understood by a person skilled in the art to which this disclosure pertains.

[0055] References to “one embodiment,” “exemplary embodiment,” “embodiment,” “some embodiments,” etc., in this disclosure indicate that while the described embodiment(s) may include specific features, structures, or characteristics, not all embodiments are required to include specific features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same embodiment(s). Moreover, when a specific feature, structure, or characteristic is described in relation to one embodiment, it is considered to be within the knowledge of a person skilled in the art to have an effect on such feature, structure, or characteristic in relation to other embodiments, whether explicitly described or not.

[0056] It should be understood that while terms such as "first" and "second" may be used to describe various elements in this specification, these elements are not to be limited by these terms. These terms are used solely to distinguish one element from another. For example, without departing from the scope of the embodiments, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element. As used in this specification, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0057] The terms used herein are intended only to describe specific embodiments and are not intended to limit exemplary embodiments. As used herein, singular forms (“a,” “an,” and “the”) are intended to include plural forms unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “has,” “having,” “includes,” and / or “including,” when used herein, specify the presence of the mentioned features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. For example, the term “includes” and variations thereof should be read as open terms meaning “includes, but is not limited to.” The term "based on" should be read as "based at least in part on." The terms "one embodiment" and "embodiment" should be read as "at least one embodiment." The term "another embodiment" should be read as "at least one other embodiment." The use of expressions such as "A and / or B" may mean "only A," "only B," or "both A and B." Other explicit and implicit definitions may be included below.

[0058] As used herein, the term “communication network” refers to a network conforming to any suitable communication standard, such as 5G NR, Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. Additionally, communications between terminal devices and network devices in a communication network may be performed according to any suitable generation communication protocol, including but not limited to first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, and fifth generation (5G) communication protocols, and / or any other protocols currently known or to be developed in the future. Embodiments of the present disclosure may be applied to various communication systems. Given the rapid advancements in communication, there may also be future types of communication technologies and systems in which the present disclosure may be embodied. This should not be construed as limiting the scope of the present disclosure to the systems described above only.

[0059] As used herein, the term “network device” generally refers to a node in a communication network where a terminal device can access the communication network and receive services therefrom. Depending on the terminology and technology applied, a network device may refer to a base station (BS) or access point (AP), e.g., a node B (NodeB or NB), a radio access network (RAN) node, an evolved node B (eNodeB or eNB), an NR NB (also referred to as gNB), a remote radio unit (RRU), a radio header (RH), an infrastructure device for vehicle-to-everything (V2X) communication, a transmit and receive point (TRP), a receive point (RP), a remote radio head (RRH), a repeater, an integrated access and backhaul (IAB) node, a low-power node such as a femto BS, a pico BS, etc.

[0060] As used herein, the term “terminal device” generally refers to any end device capable of wireless communication. By example, but not by limitation, a terminal device may also be referred to as a communication device, user equipment (UE), end-user device, subscriber station (SS), unmanned aerial vehicle (UAV), portable subscriber station, mobile station (MS), or access terminal (AT). Terminal devices may include, but are not limited to, mobile phones, cellular phones, smartphones, VoIP (voice over IP) phones, wireless local loop phones, tablets, wearable terminal devices, PDAs (personal digital assistants), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, LEE (laptop-embedded equipment), LME (laptop-mounted equipment), USB dongles, smart devices, wireless CPE (customer-premises equipment), IoT (Internet of Things) devices, watches or other wearables, HMDs (head-mounted displays), vehicles, drones, medical devices (e.g., remote surgery devices), industrial devices (e.g., robots and / or other wireless devices operating in industrial and / or automated processing chain contexts), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" may be used interchangeably.

[0061] Network Energy Saving (NES) is critical for environmental sustainability, reducing environmental impact (greenhouse gas emissions), and saving operating costs. One way to achieve NES is to introduce PRACH resource adaptation in the time domain. At a high level, this means that PRACH resources can be configured based on needs. For example, dense PRACH resources are configured for high-load scenarios, while sparse PRACH resources are configured for low-load scenarios. In this way, the number of PRACH receivers on the network side is reduced, and network energy savings are achieved.

[0062] On the other hand, in low-load scenarios where sparse PRACH resources are configured (e.g., PRACH resources are configured with long periodicity), when a RACH procedure needs to be initiated by a UE, the UE may need to wait a long time to start the RACH procedure. Furthermore, if the first RACH attempt fails, the UE needs to wait a long time to restart the RACH procedure. Therefore, it is necessary to reduce latency in RACH procedures.

[0063] With the foregoing in mind, embodiments of the present disclosure provide solutions for dynamically configuring or activating additional PRACH resources for a RACH procedure based on actual requirements while maintaining the configuration of PRACH resources having long periodicity. In an embodiment of the solution, additional PRACH resource(s) may be configured or activated by at least one of a PDCCH command, paging signaling, or a DCI for scheduling SIB1. Thus, the base station will know when a UE requires PRACH resources to initiate a RACH procedure and can dynamically configure or activate additional PRACH resources for the UE. The latency of the RACH procedure may be reduced accordingly. Aspects of the present disclosure are described in the context of a wireless communication system.

[0064] FIG. 1a illustrates an example of a wireless communication system (100) that supports PRACH resource adaptation according to aspects of the present disclosure. The wireless communication system (100) may include one or more network entities (102) (also referred to as network equipment (NE)), one or more UEs (104), a core network (106), and a packet data network (108). The wireless communication system (100) may support various radio access technologies. In some implementations, the wireless communication 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 communication system (100) may be a 5G network, such as an NR network. In other implementations, the wireless communication system (100) may be a combination of a 4G network and a 5G network, or other suitable radio access technology including IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), and IEEE 802.20. The wireless communication system (100) may support radio access technologies beyond 5G. Additionally, the wireless communication system (100) may support technologies such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), or Code Division Multiple Access (CDMA).

[0065] One or more network entities (102) may be distributed across a geographical area to form a wireless communication system (100). The one or more network entities (102) described herein may be network nodes, base stations, network elements, radio access networks (RAN), base transceiver stations, access points, NodeB, eNodeB (eNB), next-generation NodeB (gNB), or other appropriate terms, may include or be referred to as such. Network entities (102) and UEs (104) may communicate via a communication link (110) which may be wireless or wired. For example, network entities (102) and UEs (104) may perform wireless communication (e.g., receive signaling, transmit signaling) through a Uu interface.

[0066] A network entity (102) may provide a geographic coverage area (112) in which the network entity (102) can support services (e.g., voice, video, packet data, messaging, broadcast, etc.) for one or more UEs (104) within the geographic coverage area (112). For example, the network entity (102) and the UE (104) may support wireless communication of signals related to the services (e.g., voice, video, packet data, messaging, broadcast, etc.) according to one or more radio access technologies. In some implementations, the network entity (102) may be mobile and may be, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas (112) associated with the same or different radio access technologies may overlap, but different geographic coverage areas (112) may be associated with different network entities (102). The information and signals described in this specification may be represented using any of the various different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented as voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0067] One or more UEs (104) may be distributed across the entire geographical area of ​​the wireless communication system (100). The UE (104) may include or be referred to as a mobile device, wireless device, remote device, remote unit, handheld device, or subscriber device, or some other suitable term. In some implementations, the UE (104) may be referred to as a unit, station, terminal, or client, among other examples. Additionally, or alternatively, the UE (104) may be referred to as an Internet-of-Things (IoT) device, Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, the UE (104) may be stationary in the wireless communication system (100). In some other implementations, the UE (104) may be mobile in the wireless communication system (100).

[0068] One or more UEs (104) may be devices of different forms or different capabilities. Some examples of UEs (104) are illustrated in FIG. 1a. As illustrated in FIG. 1a, the UE (104) may communicate with various types of devices, such as network entities (102), other UEs (104), or network equipment (e.g., a core network (106), a packet data network (108), a relay device, an integrated access and backhaul (IAB) node, or other network equipment). Additionally, or alternatively, the UE (104) may support communication with other network entities (102) or UEs (104) that can act as relays in the wireless communication system (100).

[0069] The UE (104) may also support direct wireless communication with other UEs (104) via a communication link (114). For example, the UE (104) may support direct wireless communication with other UEs (104) via a D2D (device-to-device) communication link. In some implementations, such as V2V (vehicle-to-vehicle) deployments, V2X (vehicle-to-everything) deployments, or cellular-V2X deployments, the communication link (114) may be referred to as a side link. For example, the UE (104) may support direct wireless communication with other UEs (104) via a PC5 interface.

[0070] A network entity (102) may support communication with a core network (106), with other network entities (102), or with both. For example, a network entity (102) may interface with the core network (106) through one or more backhaul links (116) (e.g., through S1, N2, N2, or other network interfaces). Network entities (102) may communicate with each other through backhaul links (116) (e.g., through X2, Xn, or other network interfaces). In some implementations, network entities (102) may communicate directly with each other (e.g., between network entities (102)). In some other implementations, network entities (102) may communicate with each other or indirectly (e.g., through the core network (106)). In some implementations, one or more network entities (102) may include subcomponents such as an access network entity, which may be an example of an access node controller (ANC). The ANC may communicate with one or more UEs (104) through one or more other access network transmission entities, which may be referred to as a radio head, a smart radio head, or a transmission-reception point (TRP).

[0071] In some implementations, the network entity (102) may be configured as a disaggregated architecture that can be configured to utilize protocol stacks that are physically or logically distributed among two or more network entities (102), such as an integrated access backhaul (IAB) network, an open RAN (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity (102) may include one or more of a central unit (CU), a distributed unit (DU), a radio unit (RU), a RAN intelligent controller (RIC) (e.g., a near-real-time RIC, a non-real-time RIC), a service management and orchestration (SMO) system, or any combination thereof.

[0072] The RU may also be referred to as a radio head, smart radio head, remote radio head (RRH), remote radio unit (RRU), or transmission receiving point (TRP). One or more components of network entities (102) in a distributed RAN architecture may be co-located, or one or more components of network entities (102) may be located in distributed locations (e.g., separate physical locations). In some implementations, one or more network entities (102) of a distributed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0073] The functional partitioning between the CU, DU, and RU can be flexible and may support different functionalities depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combination thereof) are performed in the CU, DU, or RU. For example, a functional partitioning of the protocol stack may be utilized between the CU and the DU so that the CU can support one or more layers of the protocol stack, and the DU can support one or more different layers of the protocol stack. In some implementations, the CU may host higher protocol layer (e.g., Layer 3 (L3), Layer 2 (L2)) functionalities and signaling (e.g., Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), Packet Data Convergence Protocol (PDCP)). A CU may be connected to one or more DUs or RUs, and one or more DUs or RUs may host lower protocol layers such as Layer 1 (L1) (e.g., Physical (PHY) layer) or L2 (e.g., Radio Link Control (RLC) layer, Media Access Control (MAC) layer) functionality and signaling, and each may be controlled at least partially by the CU (160).

[0074] Additionally or alternatively, a functional partition of the protocol stack may be utilized between the DU and the RU, so that the DU can support one or more layers of the protocol stack and the RU can support one or more different layers of the protocol stack. The DU may support one or more different cells (e.g., through one or more RUs). In some implementations, the functional partition between the CU and the DU, or between the DU and the RU, may exist within the protocol layer (e.g., some functions of the protocol layer may be performed by one of the CU, DU, or RU, while other functions of the protocol layer are performed by a different of the CU, DU, or RU).

[0075] The CU can be functionally further subdivided into CU control plane (CU-CP) and CU user plane (CU-UP) functions. The CU can be connected to one or more DUs via midhaul communication links (e.g., F1, F1-c, F1-u), and the DUs can be connected to one or more RUs via fronthaul communication links (e.g., open fronthaul (FH) interfaces). In some implementations, the midhaul communication links or fronthaul communication links may be implemented according to an interface (e.g., a channel) between layers of the protocol stack supported by each network entity (102) communicating through such communication links.

[0076] The core network (106) may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network (106) may be an advanced packet core (EPC) or a 5G core (5GC), and may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME), 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, a control plane entity can manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc.), for one or more UEs (104) served by one or more network entities (102) associated with a core network (106).

[0077] The core network (106) may communicate with the packet data network (108) through one or more backhaul links (116) (e.g., via S1, N2, N2, or other network interfaces). The packet data network (108) may include an application server (118). In some implementations, one or more UEs (104) may communicate with the application server (118). The UE (104) may establish a session (e.g., a Protocol Data Unit (PDU) session) with the core network (106) through a network entity (102). The core network (106) may route traffic (e.g., control information, data, etc.) between the UE (104) and the application server (118) using the established session (e.g., an established PDU session). A PDU session may be an example of a logical connection between the UE (104) and the core network (106) (e.g., one or more network functions of the core network (106)).

[0078] In a wireless communication system (100), network entities (102) and UEs (104) may utilize the resources of the wireless communication system (100) (e.g., time resources (e.g., symbols, slots, subframes, frames, etc.) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communication). In some implementations, network entities (102) and UEs (104) may support different resource structures. For example, network entities (102) and UEs (104) may support different frame structures. In some implementations, such as in 4G, network entities (102) and UEs (104) may support a single frame structure. In some other implementations, such as in 5G, and among other suitable radio access technologies, network entities (102) and UEs (104) can support various frame structures (i.e., multiple frame structures). Network entities (102) and UEs (104) can support various frame structures based on one or more numerologies.

[0079] One or more numerologies may be supported in the wireless communication system (100), and the numerologies may include subcarrier spacing and cyclic prefixes. A first numerology (e.g., μ=0) 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., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. The fourth numerology (e.g., μ=3) may be associated with the fourth subcarrier interval (e.g., 120 kHz) and a normal cyclic prefix. The fifth numerology (e.g., μ=4) may be associated with the fifth subcarrier interval (e.g., 240 kHz) and a normal cyclic prefix.

[0080] The time interval of a resource (e.g., a communication resource) can be organized according to frames (also referred to as radio frames). Each frame may have a duration, e.g., 10 ms (milliseconds). In some implementations, each frame may contain multiple subframes. For example, each frame may contain 10 subframes, and each subframe may have a duration, e.g., 1 ms. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

[0081] Additionally or alternatively, time intervals of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may contain a number of slots (e.g., quantity). The number of slots in each subframe may also depend on one or more numerologies supported by the wireless communication system (100). For example, first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with each subcarrier interval of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may each utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and sixteen slots per subframe, respectively. Each slot may contain a number (e.g., quantity) of symbols (e.g., OFDM symbols). In some implementations, the number of slots (e.g., quantity) for a subframe may depend on the numerology. For a normal cyclic prefix, a slot may contain 14 symbols. For an extended cyclic prefix (e.g., applicable to a 60 kHz subcarrier interval), a slot may contain 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 the normal cyclic prefix and the extended cyclic prefix may depend on the numerology. It should be understood that a reference to a first numerology (e.g., μ=0) associated with a first subcarrier interval (e.g., 15 kHz) may be used interchangeably between subframes and slots.

[0082] In a wireless communication system (100), the electromagnetic (EM) spectrum may be divided into various classes, frequency bands, frequency channels, etc. based on frequency or wavelength. For example, the wireless communication system (100) may support one or more 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, network entities (102) and UEs (104) may perform wireless communication through one or more of the operating frequency bands. In some implementations, FR1 may be used by network entities (102) and UEs (104) among other equipment or devices for cellular communication traffic (e.g., control information, data). In some implementations, FR2 may be used by network entities (102) and UEs (104) among other equipment or devices for short range, high data rate capabilities.

[0083] FR1 may be associated with one or more numerologies (e.g., at least three numerologies). For example, FR1 may be associated with a first numerology including a 15 kHz subcarrier interval (e.g., μ=0); a second numerology including a 30 kHz subcarrier interval (e.g., μ=1); and a third numerology including a 60 kHz subcarrier interval (e.g., μ=2). FR2 may be associated with one or more numerologies (e.g., at least two numerologies). For example, FR2 may be associated with a third numerology including a 60 kHz subcarrier interval (e.g., μ=2); and a fourth numerology including a 120 kHz subcarrier interval (e.g., μ=3).

[0084] As previously mentioned, in 5G NR systems, random access procedures can be utilized for various purposes. For example, random access procedures can be used by a UE to find a cell to camp on during initial access; or can be used by an RRC IDLE / INACTIVE UE to switch to RRC CONNECTED mode to initiate data transmission / reception; or can be used by an RRC CONNECTED UE to re-establish lost UL synchronization, etc.

[0085] An NR 4-step random access procedure can be used for RRC IDLE / INACTIVE UEs to access a network. FIG. 1b illustrates an example of an NR 4-step random access procedure (120) that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. For the purposes of discussion, the procedure (120) will be described with reference to FIG. 1a. The procedure (120) may involve a UE (104) and a base station (102) as illustrated in FIG. 1a. Note that the 4-step random access procedure (120) is for illustrative purposes only and is not limiting. Embodiments of the present disclosure may be applied to other random access procedures.

[0086] In the random access procedure (120), the UE (104) may first transmit (122) Msg1 containing a preamble to the base station (102). After receiving Msg1, the base station (102) may transmit (124) a Random-Access Response (RAR) from Msg2 to the UE (104) to indicate the reception of the preamble and to provide information necessary for transmitting Msg3. The RAR may be received by the UE (104) within a configured time window (RAR window), which begins after a time gap following the transmission of Msg1 by the UE (104). The UE (104) may then transmit Msg3 to the base station (102) (126). The base station (102) may transmit Msg4 to the UE (104) (128). Msg3 and Msg4 can be used to resolve potential collisions resulting from simultaneous transmission of the same preamble from different UEs to the base station (102). If the UE (104) does not receive Msg2 containing RAR after transmitting Msg1, the UE (104) will treat the random access as unsuccessful and may restart the RACH procedure.

[0087] In RACH procedures, PRACH Msg1 transmission occurs in RACH opportunities (ROs), each of which occupies multiple consecutive resource blocks in the frequency domain. ROs may be composed of System Information Block Type 1 (SIB1). ROs are configured in both the time domain and the frequency domain. In the time domain, ROs are configured in every PRACH configuration period that includes a set of radio frames. Within a PRACH configuration period, a subset of subframes is indicated as including a set of PRACH slots, and within each PRACH slot, there may be one or more available ROs for PRACH transmission. Furthermore, in the frequency domain, a BS may configure multiple frequency-division-multiplexed (FDMed) ROs multiplexed in the same time opportunity.

[0088] Each RO is associated with an SSB transmitted over a specific beam. The SSBs are transmitted via beam sweeping. The UE measures the channel conditions of each SSB, selects one with good channel quality, and can transmit a preamble from the RO associated with the selected SSB. Using a beam with good channel quality for preamble transmission is beneficial from the perspective of preamble reception at the base station.

[0089] A random access procedure may be used to re-establish UL synchronization between RRC-CONNECTED UEs. FIG. 1c illustrates an example of a random access procedure (130) that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. For the purposes of discussion, the procedure (120) will be described with reference to FIG. 1a. The procedure (120) may involve a UE (104) and a base station (102) as illustrated in FIG. 1a. It should be noted that the random access procedure (130) is for illustrative purposes only and is not for limitation. Embodiments of the present disclosure may be applied to other random access procedures.

[0090] In the random access procedure (130), the base station (102) may transmit (131) a PDCCH command to the UE (104) if UL synchronization is lost on the network side. The PDCCH command is provided using DCI format 1_0, where all frequency domain assignments are set to 1, indicating that the DCI is not provided to provide downlink scheduling assignments, but rather as a PDCCH command to initiate a RACH procedure. The DCI indicates a dedicated RO and a dedicated preamble index for the UE to transmit PRACH Msg1. The DCI includes an SSB index, which indicates that the SSB should be used to determine the RO for PRACH transmission (based on the SSB-RO association). The indicated SSB corresponds to the UE's best beam. It should be noted that in legacy, the DCI does not configure ROs but only indicates which of the ROs configured in SIB1 is used for PRACH transmission. After receiving the PDCCH command, the UE (104) can transmit (132) Msg1, which includes the preamble indicated in the PDCCH command, to the base station (102) using the determined RO. After receiving Msg1, the base station (102) can transmit (134) RAR in Msg2, which indicates the reception of the preamble, to the UE (104).

[0091] Now, refer to FIG. 2, which illustrates an exemplary signaling chart of a communication process (200) that supports PRACH resource adaptation according to some exemplary embodiments of the present disclosure. For the purposes of discussion, the process (200) will be described with reference to FIG. 1a. The process (200) may involve a UE (104) and a base station (102). It should be understood that the steps and the order of the steps in FIG. 2 are for illustration only and not for limitation. It should be understood that the process (200) may include additional blocks not illustrated and / or omit some illustrated blocks, and that the scope of the present disclosure is not limited in this regard.

[0092] As illustrated in FIG. 2, the base station (102) transmits (201) to the UE (104) one of a PDCCH command (202), paging signaling (203), or a DCI (204) for scheduling SIB1. Accordingly, the UE (104) receives (203) one of the PDCCH command (202), paging signaling (203), or a DCI (204) for scheduling SIB1 from the base station (102). The received one of the PDCCH command (202), paging signaling (203), or a DCI (204) for scheduling SIB1 configures or activates at least one additional RO. That is, in addition to the set of ROs configured in SIB1, at least one additional RO is configured or activated by the base station (102). The UE (104) performs a RACH procedure (206) based on the at least one additional RO. The base station (207) monitors the preamble (207) on at least one additional RO.

[0093] For the time being, some embodiments of the PRACH resource adaptation are described in general terms. Below, some implementations of the PRACH resource adaptation will be described in more detail in relation to various specific aspects.

[0094] A first particular aspect relates to triggering the adaptation of PRACH resources by a PDCCH command. For example, when the UE (104) is in RRC CONNECTED mode and UL synchronization is lost, a PDCCH command requesting the UE (104) to start a RACH procedure to re-establish UL synchronization may be sent to the UE (104). If PRACH resources with long periodicity are configured, the UE (104) may need to wait a long time to start or restart the RACH procedure. This will result in high latency to re-establish UL synchronization.

[0095] In some embodiments of the present disclosure, at least one additional RO may include one additional RO. The additional RO is configured or enabled by the PDCCH command (202). In some implementations, the PRACH format of the additional PRACH resource may always be the same as that configured in SIB1, or may also be indicated by the PDCCH command (202).

[0096] In some implementations, the PDCCH command (202) may include resource configurations or resource allocations for additional ROs. For example, additional ROs may be configured by the PDCCH command (202). When the UE (104) receives the PDCCH command (202), the UE (104) may initiate a RACH procedure on the additional RO configured by the PDCCH command (202). The PDCCH command (202) allocates at least time domain and frequency domain resources for the additional ROs. For example, the starting OFDM symbol and starting PRB of the additional ROs are indicated in the PDCCH command (202). It should be noted that the number of OFDM symbols and physical resource blocks (PRBs) is not indicated but may be determined by the PRACH format. The reserved bits (12 bits) in the PDCCH command (202) may be reused for the allocation of time domain and frequency domain resources.

[0097] In some implementations, the UE (104) may receive resource configurations for additional ROs carried in Media Access Control (MAC) control element (CE) signaling or Radio Resource Control (RRC) signaling from the base station (102). The PDCCH command (202) may include an indication to enable additional ROs. For example, additional PRACH resources may be configured semi-statically by RRC / MAC signaling and enabled by an information element in the PDCCH command (202).

[0098] In some implementations, additional ROs are associated with the SSB indicated in the PDCCH command (202). Since the indicated SSB already corresponds to the UE's best beam, there is no need to associate additional ROs with other SSBs. This further reduces power consumption at the base station side during PRACH detection.

[0099] In some implementations, the additional RO is a first additional RO. When performing the RACH procedure, the UE (104) can transmit a preamble on the first additional RO to the base station (102) and monitor a RAR message indicating the reception of the preamble in the RAR window. The time offset between the PDCCH command (202) and the first slot having the first additional RO may be configured or predefined by the base station (102). That is, there may be a predefined or configured timing offset between the PDCCH command (202) (i.e., DCI) and the first slot having the additional RO. Based on this timing, the UE (104) can know when the additional RO is available.

[0100] In some implementations, if no RAR message is received in the RAR window, the UE (104) may perform a second RACH procedure based on a second additional RO. The time offset between the end of the RAR window and the second slot having the second additional RO is configured or predefined by the base station (102). The second additional RO may have the same configuration as the first additional RO. That is, if a preamble is transmitted from the additional RO but no RAR message is received, the additional RO may be available. In a more specific example, if a PRACH preamble is transmitted from the additional RO but no RAR is received by the UE (104), the UE (104) may assume that the additional RO is still available after a predefined or configured time offset from the end of the RAR window. The UE (104) may retransmit PRACH from the additional RO with higher transmit power.

[0101] Now, refer to FIG. 3, which illustrates an example (300) of PRACH resource adaptation by a PDCCH command according to some exemplary embodiments of the present disclosure. In example (300), a set of PRACH resources is configured in SIB1. Legacy ROs correspond to the PRACH resources configured in SIB1 and have long cycles. That is, legacy ROs are used by UEs that do not support additional ROs or PRACH resource adaptation. In addition to the legacy ROs, additional ROs are configured or triggered by a PDCCH command. Upon receiving a PDCCH command, a UE that supports additional PRACH adaptation can start a PRACH procedure from the additional ROs instead of waiting a long time to start a procedure from the legacy ROs. Thus, the latency of the PRACH procedure can be reduced.

[0102] Referring again to FIG. 2, a second specific embodiment relates to triggering PRACH resource adaptation by paging signaling. The UE will initiate the RACH procedure after receiving a paging message. Paging of the UE primarily occurs when DL data arrives from the network for the UE. When the UE is paged at a paging occasion (PO), if only RACH resources with long periodicity are available, and the available ROs are far from the PO, the UE needs to wait a long time to initiate the RACH procedure. Furthermore, even if the available ROs are near the PO, if the first PRACH attempt fails, the UE may need to wait a long time to restart the RACH procedure. This will result in high latency for the UE accessing the network when the UE is paged.

[0103] In some implementations, at least one additional RO may include a set of additional ROs. The set of additional ROs is configured or enabled by paging signaling (203). Paging signaling (203) may be one of a paging message, a paging DCI for scheduling a paging message, or a paging early indication (PEI) indicating the presence of a paging message. That is, additional PRACH resources for the UE (104) may be configured or enabled by paging signaling, which is a paging DCI or a PEI or a paging message. When the UE (104) is paged, the UE (104) may start or restart the RACH procedure on the additional PRACH resources.

[0104] In some implementations, the UE (104) may transmit to a network device an indication of its ability to support PRACH resource adaptation triggered by paging signaling. The network device may be implemented as a device for performing access and mobility management functions (AMF). The network device may transmit to a base station (102) an indication of the UE (104)'s ability to support PRACH resource adaptation triggered by paging signaling. In this way, the base station can identify UEs that support additional PRACH resource allocation, so that when a UE that supports additional PRACH resource allocation is paged, the base station can configure additional PRACH resources for the UE.

[0105] FIG. 4 illustrates an exemplary signaling chart of a communication process (400) that supports PRACH resource adaptation by paging signaling according to some exemplary embodiments of the present disclosure. For the purposes of discussion, the process (400) will be described with reference to FIG. 1a. The process (400) may involve a UE (104) and a base station (102) as shown in FIG. 1a, and an AMF (106-1) not shown in FIG. 1a. The AMF (106-1) may be a network function in the core network (106) of FIG. 1a. It should be understood that the steps and the order of the steps in FIG. 4 are for illustrative purposes only and not for limitation. It should be understood that the process (400) may include additional blocks not shown and / or may omit some of the blocks shown, and that the scope of the present disclosure is not limited in this regard. The process (400) may be considered as a specific example of the process (200) of FIG. 2.

[0106] In process (400), at 401, the UE (104) reports to the AMF (106-1) about its ability to support the configuration of additional PRACH resources. This reporting may be performed via NAS signaling when the UE (104) registers with the network. At 402, the AMF (106-1) indicates to the base station (102) which UEs support PRACH resource adaptation. When the base station (102) pages a UE having such ability, the base station (102) may trigger additional PRACH resources to be available in the paging signaling. For example, at 403, the base station (102) obtains a paging message for the UE (104). Since the base station (102) knows about the UE's ability to support the configuration of additional PRACH resources, at 404, the base station (102) may send a paging message to the UE (104) to activate the additional PRACH resources. In 405, the UE (104) can transmit a PRACH preamble from additional PRACH resources.

[0107] In some implementations, the paging signaling (203) may include resource configurations for a set of additional ROs. That is, additional ROs may be configured by the paging signaling.

[0108] In some implementations, the UE (104) may receive SIB1 from the base station (102). SIB1 may include resource configurations for a set of additional ROs. The paging signaling (203) may include an indicator that activates a set of additional ROs. That is, in addition to configuring PRACH resources with a PRACH configuration cycle, SIB1 may additionally configure a set of additional PRACH resources. A set of additional PRACH resources may be configured in SIB1 and activated by an indicator in the paging signaling. In one embodiment, the indicator may be a 1-bit indicator that is newly added to the paging signaling or reuses a reserved bit in the paging signaling, e.g., a short message indicator.

[0109] In some implementations, the UE (104) may receive SIB1 from the base station (102). SIB1 may include resource configurations for at least one set of additional ROs. At least one set of additional ROs may include a set of additional ROs. Paging signaling (203) may include an indication of a set of additional ROs. A set of additional ROs is activated by paging signaling (203). That is, in addition to configuring PRACH resources having a PRACH configuration cycle, SIB1 may additionally configure multiple sets of additional PRACH resources, and paging signaling may indicate which set of additional PRACH resources will be activated.

[0110] In some implementations, the time offset between the last monitoring opportunity for the paging DCI and the first slot having a set of additional ROs may be configured or predefined by the base station (102). Alternatively, the time offset between the last slot having the paging message and the first slot having a set of additional ROs may be configured or predefined by the base station (102). In some implementations, at least one additional RO is available in a time window, and the time window is configured or predefined by the base station (102).

[0111] Now, refer to FIG. 5, which illustrates an example (500) of PRACH resource adaptation by paging signaling according to some exemplary embodiments of the present disclosure. In the example (500), PO#0 (521) includes four PDCCH monitoring opportunities (521-1, 521-2, 521-3, and 521-4) for a paging DCI. Each monitoring opportunity is associated with a specific beam. When a paging DCI is received at a monitoring opportunity (e.g., PDCCH monitoring opportunity (521-3)), a UE supporting PRACH resource adaptation may determine a set of additional PRACH resources. There may be a predefined or configured time offset t between the last PDCCH monitoring opportunity for the paging DCI (e.g., PDCCH monitoring opportunity (521-4)) and the first slot having additional PRACH resources, or between the last slot having a paging message and the first slot having additional PRACH resources. Based on this timing, the UE will know when additional PRACH resources are available. Furthermore, a time window for the availability of additional PRACH resources can be configured. In example (500), additional PRACH resources (511-1, 511-2, 511-3, 511-4 and 512-1, 512-2, 512-3, 512-4) are available. PDCCH monitoring opportunities and additional ROs associated with the same beam are shown in the same shading in FIG. 5. When the UE is paginated, the UE can start a RACH procedure in an additional RO instead of waiting a long time to start a procedure in a legacy RO. For example, if the UE receives a pagination DCI in a PDCCH monitoring opportunity (521-3), the UE can start a RACH procedure in a first additional RO (511-3) associated with the same beam as the PDCCH monitoring opportunity (521-3).

[0112] Returning to FIG. 2, a third specific aspect relates to triggering PRACH resource adaptation by a DCI for scheduling SIB1. In some implementations, at least one additional RO may include a set of additional ROs. The set of additional ROs is enabled by the DCI (204) for scheduling SIB1. The DCI (204) for scheduling SIB1 may include an indication of the availability of the set of additional ROs. SIB1 may include resource configurations for the set of additional ROs.

[0113] That is, additional PRACH resources can be triggered in the DCI for scheduling SIB1, which is transmitted periodically using a beam sweeping method. Using the DCI for scheduling SIB1 to trigger the activation of additional PRACH resources can avoid frequent changes to SIB1 and is therefore advantageous in terms of avoiding frequent signaling of SIB1 detection and system information modification. Information elements in the SIB1 DCI can be used to indicate the availability of additional PRACH resources. For example, reserved bits in the SIB1 DCI can be used for indication. From the perspective of the UE (104), when the UE (104) receives SIB1 and acquires the indication, the UE (104) reads SIB1 and acquires the configured additional PRACH resources.

[0114] In some implementations, the time offset between the last slot having a DCI (204) for scheduling SIB1 and the first slot having a set of additional ROs is configured or predefined by the base station (102). Alternatively, the time offset between the last slot having SIB1 and the first slot having a set of additional ROs is configured or predefined by the base station (102). In some implementations, at least one additional RO is available in a time window, and the time window is configured or predefined by the base station (102). That is, there may be a time offset that is predefined or configured between the last slot having a DCI for scheduling SIB1 and the first slot having additional PRACH resources, or between the last slot having SIB1 and the first slot having additional PRACH resources. Based on this timing, the UE (104) will know when the additional PRACH resources are available. Furthermore, a time window in which the additional PRACH resources are available may be configured.

[0115] A fourth specific aspect relates to the SSB-to-RO association for additional ROs. As mentioned above, for additional ROs configured or enabled by the PDCCH command (202) used by RRC CONNECTED UEs, the additional RO is associated with the SSB indicated in the PDCCH command (202). For additional ROs configured or enabled by the DCI for paging signaling or scheduling SIB1, which are primarily used by RRC IDLE / INACTIVE UEs, the additional ROs must be associated with all available SSBs (indicated in the SIB) because the base station has no knowledge of which beam will be selected by the UE (104) for preamble transmission. To avoid affecting the SSB-to-RO association for legacy ROs, the SSB-to-RO association for additional ROs may be determined separately. However, this means that a UE supporting additional PRACH adaptation needs to maintain two associations: one for legacy ROs configured in SIB1 and the other for additional ROs. This can lead to higher complexity on the UE side.

[0116] In some implementations, the UE (104) receives SIB1 from the base station (102), determines a set of ROs based on SIB1, and can perform an integrated SSB-to-RO association for the set of ROs and at least one additional RO. That is, an integrated SSB-to-RO association for the legacy ROs and the additional ROs can be implemented without changing the SSB-to-RO association of the legacy ROs.

[0117] In some implementations, at least one additional RO may include a set of additional ROs. To perform an integrated SSB-to-RO association, the UE may perform a first SSB-to-RO association for a set of legacy ROs and determine a second SSB-to-RO association for a set of additional ROs based on the first SSB-to-RO association. In some examples, the second SSB-to-RO association may follow the first SSB-to-RO association in a sequential and wrap-round manner. That is, in the integrated SSB-to-RO association, the UE (104) may perform an SSB-to-RO association of legacy ROs, and then an SSB-to-RO association for additional ROs may be determined based on the SSB-to-RO association of legacy ROs. In one embodiment, additional ROs are associated with SSBs in a sequential and wrap-round manner.

[0118] For example, the available SSBs in the network are {SSB#k_1, SSB#k_2, SSB#k_3,..., SSB#k_N}, where k_1 <k_2<k_3<...<k_N인 것으로 가정한다. SSB들 및 레거시 RO들이 일-대-일 맵핑되거나 일-대-M 맵핑되고, 추가적인 RO들의 세트 이전의 마지막 레거시 RO가 SSB#k_n에 맵핑되는 경우, 추가적인 RO들의 세트 이전의 제1 추가적인 RO는 SSB#k_n+1에 맵핑될 것이다. SSB들 및 레거시 RO들이 일-대-일 맵핑되거나 일-대-M 맵핑되고, 추가적인 RO들의 세트 이전의 마지막 레거시 RO가 SSB#k_N에 맵핑되는 경우, 추가적인 RO들의 세트의 제1 추가적인 RO는 SSB#k_1에 맵핑될 것이다. SSB들 및 레거시 RO들이 M-대-1 맵핑되고, 추가적인 RO들의 세트 이전의 마지막 레거시 RO가 SSB#k_n-M+1 내지 SSB#k_n에 맵핑되는 경우, 추가적인 RO들의 세트 중의 제1 추가적인 RO는 SSB#k_n+1 내지 SSB#k_n+M에 맵핑될 것이다. SSB들 및 레거시 RO들이 M-대-1 맵핑되고, 추가적인 RO들의 세트 이전의 마지막 레거시 RO가 SSB#k_N-M+1 내지 SSB#k_N에 맵핑되는 경우, 추가적인 RO들의 세트 중의 제1 추가적인 RO는 SSB#k_1 내지 SSB#k_M에 맵핑될 것이다.

[0119] Now, refer to FIG. 6, which illustrates an example (600) of an SSB-to-RO association according to some exemplary embodiments of the present disclosure. In example (600), SSBs and legacy ROs are mapped one-to-one. The last legacy RO (601) prior to the configured set of additional ROs is mapped to SSB#3, and the first additional RO (611) of the configured set of additional ROs is mapped to SSB#4. SSBs are mapped sequentially to additional ROs and legacy ROs.

[0120] Returning to FIG. 2, in some implementations, the UE (104) may determine that at least one of the additional ROs is invalid if the additional RO overlaps with one of the sets of ROs. That is, the configured additional RO(s) conflict with the legacy ROs in the slot, and the UE (104) and the base station (102) may treat the additional RO(s) that conflict with the legacy ROs as invalid ROs, which cannot be used for PRACH transmission.

[0121] In some implementations, the UE (104) may determine that one or more sets of additional ROs are invalid if at least one of the sets of ROs following the one or more additional ROs cannot form an SSB-to-RO mapping cycle. Now, refer to FIG. 7, which illustrates another example (700) of an SSB-to-RO association according to some exemplary embodiments of the present disclosure. In example (700), after performing an integrated SSB-to-RO association, four additional ROs (711, 712, 713, and 714) cannot form a mapping cycle. These ROs are invalid ROs and cannot be used for PRACH transmission.

[0122] FIG. 8 illustrates an example of a device (800) that supports PRACH resource adaptation according to aspects of the present disclosure. The device (800) may be an example of a UE (104) or base station (102) as described herein. The device (800) may support wireless communication with one or more network entities (102), UEs (104), or any combination thereof. The device (800) may include components for bidirectional communication, such as a processor (802), memory (804), a transceiver (806), and optionally an I / O controller (808), for transmitting and receiving communications. These components may communicate electronically through one or more interfaces (e.g., a bus) or otherwise be coupled (e.g., kinetically, communically, functionally, electronically, electrically).

[0123] A processor (802), memory (804), transceiver (806), or various combinations thereof or various components thereof may be examples of means for carrying out various aspects of the present disclosure as described herein. For example, a processor (802), memory (804), transceiver (806), or various combinations thereof or components thereof may support a method for carrying out one or more of the operations described herein.

[0124] In some implementations, the processor (802), memory (804), transceiver (806), or various combinations or components thereof may be implemented in hardware (e.g., as a communication management circuit). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as a means for performing the functions described in this disclosure or otherwise supporting such means. In some implementations, the processor (802) and the memory (804) coupled with the processor (802) may be configured to perform one or more of the functions described herein (e.g., to execute instructions stored in the memory (804) by the processor (802).

[0125] In one example, the processor (802) may support wireless communication in the device (800) according to examples as disclosed herein. The processor (802) may be configured to operate to support means for receiving from a base station one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) - SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or activates at least one additional RO - and means for performing a RACH procedure based on at least one additional RO.

[0126] In another example, the processor (802) may support wireless communication in the device (800) according to the examples disclosed herein. The processor (802) may be configured to operate to support means for transmitting to a user equipment (UE) one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) - SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or activates at least one additional RO -; and means for monitoring a preamble on at least one additional RO.

[0127] The processor (802) may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some implementations, the processor (802) may be configured to operate a memory array using a memory controller. In some other implementations, the memory controller may be integrated into the processor (802). The processor (802) may be configured to execute computer-readable instructions stored in memory (e.g., memory (804)) to enable the device (800) to perform various functions of the present disclosure, so that the device (800) may perform any process of the present disclosure as discussed with reference to FIGS. 2 through 7b.

[0128] Memory (804) may include random access memory (RAM) and read-only memory (ROM). Memory (804) may store computer-readable, computer-executable code containing instructions that, when executed by the processor (802), enable the device (800) to perform the various functions described herein. The code may be stored in a non-transient computer-readable medium, such as system memory or other types of memory. In some implementations, the code may not be directly executable by the processor (802) but may enable the computer to perform the functions described herein (e.g., when compiled and executed). In some implementations, memory (804) may include a basic I / O system (BIOS) capable of controlling basic hardware or software operations, such as interactions with peripheral components or devices, among other things.

[0129] The I / O controller (808) can manage input and output signals for the device (800). The I / O controller (808) can also manage peripherals that are not integrated into the device (M02). In some implementations, the I / O controller (808) may represent a physical connection or port to an external peripheral. In some implementations, the I / O controller (808) may use an operating system such as iOS®, ANDROID®, MS-WINDOWS®, OS / 2®, UNIX®, LINUX®, or other known operating systems. In some implementations, the I / O controller (808) may be implemented as part of a processor such as the processor (802). In some implementations, a user may interact with the device (800) through the I / O controller (808) or through hardware components controlled by the I / O controller (808).

[0130] In some implementations, the device (800) may include a single antenna (810). However, in some other implementations, the device (800) may have more than one antenna (810) (i.e., multiple antennas), including multiple antenna panels or antenna arrays capable of simultaneously transmitting or receiving multiple wireless transmissions. The transceiver (806) may communicate bidirectionally through one or more antennas (810), wired, or wireless links, as described herein. For example, the transceiver (806) may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver (806) may also include a modem that modulates packets, provides the modulated packets to one or more antennas (810) for transmission, and demodulates packets received from one or more antennas (810). The transceiver (806) may include one or more transmission chains, one or more reception chains, or a combination thereof.

[0131] A transmission chain may be configured to generate and transmit signals (e.g., control information, data, packets). The transmission chain may include at least one modulator for modulating data on a carrier signal and 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 such as phase shift keying (PSK) or quadrature amplitude modulation (QAM). The transmission chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over a wireless medium. The transmission chain may also include one or more antennas (810) for transmitting the amplified signal over the air or a wireless medium.

[0132] A receiving chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, a receiving chain may include one or more antennas (810) for receiving signals over an air or wireless medium. A receiving chain may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. A receiving chain may include at least one demodulator configured to obtain transmitted data by demodulating the received signal and reversing the modulation technique applied during the transmission of the signal. A receiving chain may include at least one decoder for decoding the demodulated signal to receive the transmitted data.

[0133] FIG. 9 illustrates an example of a processor (900) that supports PRACH resource adaptation according to aspects of the present disclosure. The processor (900) may be an example of a processor configured to perform various operations according to the examples described herein. The processor (900) may be implemented as a device or its components as described herein. For example, the device may be an example of a UE (104) or base station (102) as described herein. The processor (900) may include a controller (902) configured to perform various operations according to the examples described herein. The processor (900) may optionally include at least one memory (904), such as an L1 / L2 / L3 cache. Additionally or alternatively, the processor (900) may optionally include one or more arithmetic logic units (ALUs) (900). One or more of these components may communicate electronically through one or more interfaces (e.g., a bus) or be combined in other ways (e.g., kinetically, communically, functionally, electronically, electrically).

[0134] The processor (900) may be a processor chipset and may include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, acquiring, searching, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) according to examples 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., processor (900)) 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), etc.).

[0135] A controller (902) may be configured to manage and coordinate various operations of the processor (900) (e.g., signaling, receiving, acquiring, searching, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) so that the processor (900) supports various operations according to examples described herein. For example, the controller (902) may operate as a control unit of the processor (900) and generate control signals that manage the operations of various components of the processor (900). These control signals include enabling or disabling function units, selecting data paths, initiating memory access, and coordinating the timing of operations.

[0136] The controller (902) may be configured to fetch instructions from memory (904) (e.g., acquire, retrieve, receive) and to determine subsequent instruction(s) to be executed in order to enable the processor (900) to support various operations according to examples described herein. The controller (902) may be configured to track memory addresses of instructions associated with memory (904). The controller (902) may be configured to decode instructions to determine operations to be performed and accompanying operands. For example, the controller (902) may be configured to interpret instructions and determine control signals to be output to other components of the processor (900) so that the processor (900) can support various operations according to examples described herein. Additionally or alternatively, the controller (902) may be configured to manage the flow of data within the processor (900). The controller (902) may be configured to control the transfer of data between the registers, arithmetic logic units (ALUs), and other functional units of the processor (900).

[0137] Memory (904) may include one or more caches (e.g., memory local to or included in the processor (900), or other memory such as RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc.). In some implementations, memory (904) may reside within or on a processor chipset (e.g., local to the processor (900)). In some other implementations, memory (904) may reside outside the processor chipset (e.g., remotely from the processor (900)).

[0138] Memory (904) may store computer-readable, computer-executable code containing instructions that, when executed by the processor (900), cause the processor (900) to perform the various functions described herein. The code may be stored in a non-transient computer-readable medium, such as system memory or other types of memory. A controller (902) and / or a processor (900) may be configured to execute computer-readable instructions stored in memory (904) to cause the processor (900) to perform the various functions. For example, the processor (900) and / or the controller (902) may be coupled to or with memory (904), and the processor (900), the controller (902), and memory (904) may be configured to perform the various functions described herein. In some examples, the processor (900) may include a plurality of processors, and memory (904) may include a plurality of memories. One or more of the plurality of processors may be combined with one or more of the plurality of memories, and they may be configured to perform various functions as described herein, individually or collectively.

[0139] One or more ALUs (900) may be configured to support various operations according to the examples described herein. In some implementations, one or more ALUs (900) may reside within or on a processor chipset (e.g., processor (900)). In some other implementations, one or more ALUs (900) may reside outside a processor chipset (e.g., processor (900)). One or more ALUs (900) may perform one or more operations on data, such as addition, subtraction, multiplication, and division. For example, one or more ALUs (900) may receive input operands and an operation code that determines the operation to be executed. One or more ALUs (900) are composed of various logic and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate data according to the operation. Additionally or alternatively, one or more ALUs (900) support logical operations such as AND, OR, XOR (exclusive-OR), NOR (not-OR), and NAND (not-AND), enabling one or more ALUs (900) to handle conditional operations, comparisons, and bitwise operations.

[0140] In the example, the processor (900) may support wireless communication according to examples as disclosed in this specification. The processor (900) may be configured or operable to support means for receiving from a base station one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) - SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or activates at least one additional RO - and means for performing a RACH procedure based on at least one additional RO.

[0141] In another example, the processor (900) may support wireless communication according to examples as disclosed herein. The processor (900) may be configured or operable to support means for transmitting to a user equipment (UE) one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) - SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or enables at least one additional RO - and means for monitoring a preamble on at least one additional RO.

[0142] FIG. 10 illustrates a flowchart of a method (1000) that supports PRACH resource adaptation according to embodiments of the present disclosure. Operations of the method (1000) may be implemented by a device or its components as described herein. For example, operations of the method (1000) may be performed by a UE (104) as described herein. In some implementations, the device may execute a set of instructions to control functional elements of the device to perform the described functions. Additionally or alternatively, the device may perform embodiments of the described functions using special-purpose hardware.

[0143] In 1005, the method may include the step of receiving from a base station one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling system information block 1 (SIB1), and SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or enables at least one additional RO. The operations of 1005 may be performed according to the examples described herein. In some implementations, aspects of the operations of 1005 may be performed by a device such as that described with reference to FIG. 1a.

[0144] In 1010, the method may include the step of performing a RACH procedure based on at least one additional RO. The operations of 1010 may be performed according to the examples described herein. In some implementations, aspects of the operations of 1010 may be performed by a device such as that described with reference to FIG. 1a.

[0145] FIG. 11 illustrates a flowchart of a method (1100) for supporting requests for PRACH resources according to embodiments of the present disclosure. Operations of the method (1100) may be implemented by a device or its components as described herein. For example, operations of the method (1100) may be performed by a base station (102) as described herein. In some implementations, the device may execute a set of instructions to control functional elements of the device to perform the described functions. Additionally or alternatively, the device may perform embodiments of the described functions using special-purpose hardware.

[0146] In 1105, the method may include the step of transmitting to a user device (UE) one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling system information block 1 (SIB1), and SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, paging signaling, or DCI for scheduling SIB1 constitutes or enables at least one additional RO. The operations of 1105 may be performed according to the examples described herein. In some implementations, aspects of the operations of 1105 may be performed by a device such as that described with reference to FIG. 1a.

[0147] In 1110, the method may include the step of monitoring the preamble in at least one additional RO. The operations of 1110 may be performed according to the examples described herein. In some implementations, aspects of the operations of 1110 may be performed by a device such as that described with reference to FIG. 1a.

[0148] FIG. 12 illustrates a flowchart of a method (1200) that supports PRACH resource adaptation according to embodiments of the present disclosure. Operations of the method (1200) may be implemented by a device or its components as described herein. For example, operations of the method (1200) may be performed by an AMF (106-1) as described herein. In some implementations, the device may execute a set of instructions to control functional elements of the device to perform the described functions. Additionally or alternatively, the device may perform embodiments of the described functions using special-purpose hardware.

[0149] In 1205, the method may include the step of receiving from a user device (UE) an indication of the UE's ability to support physical random access channel (PRACH) resource adaptation triggered by paging signaling. The operations of 1205 may be performed according to examples as described herein. In some implementations, aspects of the operations of 1205 may be performed by a device as described with reference to FIG. 1a.

[0150] In 1210, the method may include the step of transmitting to a base station an indication of the UE's ability to support PRACH resource adaptation triggered by paging signaling. The operations of 1210 may be performed according to examples as described herein. In some implementations, aspects of the operations of 1210 may be performed by a device as described with reference to FIG. 1a.

[0151] It should be noted that the methods described in this specification describe possible implementations, and that operations and steps may be rearranged or modified in other ways, and that other implementations are possible. Additionally, aspects from two or more of the methods may be combined.

[0152] The various exemplary blocks and components described in connection with the disclosures in this specification may be implemented or performed as general-purpose processors, DSPs, ASICs, CPUs, FPGAs or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this specification. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors associated with a DSP core, or any other combination of such configurations).

[0153] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software executed by a processor, the functions may be stored on a computer-readable medium or transmitted therethrough as one or more instructions or codes on a computer-readable medium. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of the software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features implementing the functions may be physically placed in various locations, including distributed so that parts of the functions are implemented in different physical locations.

[0154] Computer-readable media include both non-transient computer storage media and communication media, comprising any medium that facilitates the transfer of computer programs from one place to another. Non-transient storage media may be any available medium that can be accessed by a general-purpose or special-purpose computer. For example, non-transient computer-readable media may include RAM, ROM, EEPROM (electrically erasable programmable ROM), flash memory, CD (compact disk) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transient medium that can be used to carry or store desired means of program code in the form of instructions or data structures and can be accessed by a general-purpose or special-purpose computer or a general-purpose or special-purpose processor.

[0155] As used herein, including in the claims, the singular expression (article "a") preceding an element is not limited and is understood to refer to "at least one" of such elements or "one or more" of such elements. The terms singular expression (article "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, the word "or" as used in a list of items (e.g., a list of items followed by phrases such as "at least one of," "one or more of," or "one or both of") indicates a comprehensive 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, B, and C). Furthermore, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an exemplary step described as “based on Condition A” may be based on both Condition A and Condition B without departing from the scope of the present disclosure. That is, as used herein, the phrase “based on” should be interpreted in the same way as the phrase “at least partially based on”. Additionally, as used herein, including in the claims, a “set” may include one or more elements.

[0156] The description in this specification is provided to enable a person skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to a person skilled in the art, and the general principles defined in this specification may be applied to other variations without departing from the scope of the present disclosure. Accordingly, the present disclosure is not limited to the examples and designs described in this specification, but should be given the broadest scope consistent with the principles and novel features disclosed in this specification.

Claims

Claim 1 As user equipment, the processor; and a transceiver coupled to the processor, wherein the processor Receiving, through the transceiver, one of a Physical Downlink Control Channel (PDCCH) command, paging signaling, or Downlink Control Information (DCI) for scheduling System Information Block 1 (SIB1) from a base station—wherein SIB1 constitutes a set of Random Access Channel (RACH) Opportunities (ROs), and one of the PDCCH command, the paging signaling, or the DCI for scheduling SIB1 constitutes or activates at least one additional RO—; User equipment configured to perform a RACH procedure based on at least one additional RO. Claim 2 In claim 1, the at least one additional RO comprises one additional RO, said additional RO is configured or enabled by said PDCCH command, said additional RO is associated with a synchronization signal and a physical broadcast channel (PBCH) block (SSB) indicated in said PDCCH command, a UE. Claim 3 In paragraph 2, the above PDCCH command is a UE including resource configurations for the additional RO. Claim 4 In paragraph 2, the additional RO is a first additional RO, and performing the RACH procedure comprises transmitting a preamble on the first additional RO to the base station via the transceiver—the time offset between the PDCCH command and the first slot having the first additional RO is configured or predefined by the base station—; and monitoring a Random Access Response (RAR) message indicating reception of the preamble in a RAR window, UE. Claim 5 In paragraph 4, the processor is further configured to perform a second RACH procedure based on a second additional RO when a RAR message is not received in the RAR window, and the time offset between the end of the RAR window and the second slot having the second additional RO is configured or predefined by the base station, UE. Claim 6 In claim 1, the at least one additional RO comprises a set of the additional ROs, the set of additional ROs is configured or activated by the paging signaling, and the paging signaling is one of a paging message; a paging DCI for scheduling the paging message; or a paging early indication (PEI) indicating the presence of the paging message, a UE. Claim 7 In claim 6, the processor is further configured to transmit to a network device, via the transceiver, an indication of the ability to support physical RACH (PRACH) resource adaptation triggered by the paging signaling, a UE. Claim 8 In paragraph 6, the processor is further configured to receive the SIB1 from the base station via the transceiver, the SIB1 includes resource configurations for the set of additional ROs; and the paging signaling includes an indication to activate the set of additional ROs, UE. Claim 9 In paragraph 6, the processor is further configured to receive the SIB1 from the base station via the transceiver, the SIB1 comprising resource configurations for at least one additional set of ROs, the at least one set of additional ROs comprising the set of additional ROs; the paging signaling comprises an indication of the set of additional ROs, and the set of additional ROs is activated by the paging signaling, UE. Claim 10 In paragraph 6, the time offset between the last monitoring opportunity for the paging DCI and the first slot having the set of additional ROs is configured or predefined by the base station; or the time offset between the last slot having the paging message and the first slot having the set of additional ROs is configured or predefined by the base station, wherein the UE is one of these. Claim 11 In claim 1, the at least one additional RO comprises a set of additional ROs, the set of additional ROs is activated by the DCI for scheduling the SIB1, the DCI for scheduling the SIB1 comprises an indication of the availability of the set of additional ROs, and the SIB1 comprises resource configurations for the set of additional ROs, UE. Claim 12 In claim 11, the time offset between the last slot having the DCI for scheduling the SIB1 and the first slot having a set of additional ROs is configured or predefined by the base station; or the time offset between the last slot having the SIB1 and the first slot having a set of additional ROs is configured or predefined by the base station, wherein the UE is one of these. Claim 13 In paragraph 1, the at least one additional RO is available in a time window, and the time window is configured or predefined by the base station, UE. Claim 14 In claim 1, the processor is further configured to receive the SIB1 from a base station via the transceiver; determine the set of ROs based on the SIB1; and perform an integrated SSB-to-RO association for the set of ROs and the at least one additional RO, the UE. Claim 15 In paragraph 14, the above at least one additional RO comprises a set of additional ROs, and performing the integrated SSB-to-RO association comprises: performing a first SSB-to-RO association for the set of ROs; and determining a second SSB-to-RO association for the set of additional ROs based on the first SSB-to-RO association, UE. Claim 16 In paragraph 15, determining the second SSB-to-RO association comprises causing the second SSB-to-RO association to follow the first SSB-to-RO association in a sequential and wrap-round manner, UE. Claim 17 In paragraph 1, the processor is further configured to determine that one of the at least one additional RO is invalid, and the additional RO overlaps with one of the sets of ROs, UE. Claim 18 As a base station, it includes a processor; and a transceiver coupled to the processor, wherein the processor, Through the above transceiver, one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) is transmitted to a user device (UE) - said SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and said PDCCH command, said paging signaling, or said DCI for scheduling said SIB1 constitutes or activates at least one additional RO -; A base station configured to monitor a preamble on at least one additional RO. Claim 19 A method performed by user equipment comprising the step of receiving from a base station one of a physical downlink control channel (PDCCH) command, paging signaling, or downlink control information (DCI) for scheduling a system information block 1 (SIB1) - wherein the SIB1 constitutes a set of random access channel (RACH) opportunities (RO), and one of the PDCCH command, the paging signaling, or the DCI for scheduling the SIB1 constitutes or activates at least one additional RO -; and performing a RACH procedure based on the at least one additional RO. Claim 20 A processor for wireless communication comprising: at least one memory; and a controller coupled to said at least one memory, wherein the controller causes said controller, Receiving from a base station one of a Physical Downlink Control Channel (PDCCH) command, paging signaling, or Downlink Control Information (DCI) for scheduling System Information Block 1 (SIB1) - said SIB1 constitutes a set of Random Access Channel (RACH) Opportunities (ROs), and said PDCCH command, said paging signaling, or said DCI for scheduling said SIB1 constitutes or activates at least one additional RO -; A processor for wireless communication configured to perform a RACH procedure based on at least one additional RO.

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