BURST ARRIVAL TIME REPORTING ENHANCEMENTS FOR XR

Apparatus, methods, and computer program products for wireless communication are provided. An example method may include receiving, from a user equipment (UE), a burst arrival time (BAT) report including BAT information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session. The example method may further include transmitting, for a second network node, the BAT information associated with the at least one QoS flow.

TECHNICAL FIELD

The present disclosure relates generally to communication systems, and more particularly, to wireless communication systems burst arrival time reporting.

INTRODUCTION

BRIEF SUMMARY

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus at a first network node are provided. The apparatus may include at least one memory and at least one processor coupled to the at least one memory. Based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to receive, from a user equipment (UE), a burst arrival time (BAT) report including BAT information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session. Based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to transmit, for a second network node, the BAT information associated with the at least one QoS flow.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus at a first network node are provided. The apparatus may include at least one memory and at least one processor coupled to the at least one memory. Based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to receive, from a second network node, burst arrival time (BAT) information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session of a user equipment (UE). Based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to configure, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG).

DETAILED DESCRIPTION

Arrival times of extended reality (XR) traffic may vary. For example, XR traffic bursts may arrive and be available for transmission at a time that is earlier or later than a time at which a user equipment (UE) (or a base station) expects the XR traffic bursts. To support XR in dual connectivity (DC) scenarios, burst arrival time (BAT) reporting may be supported. Aspects provided herein may enable support of BAT reporting in XR DC.

FIG. 1 is a diagram 100 illustrating an example of a wireless communications system and an access network. The illustrated wireless communications system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs 110 that can communicate directly with a core network 120 via a backhaul link, or indirectly with the core network 120 through one or more disaggregated base station units (such as a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC) 125 via an E2 link, or a Non-Real Time (Non-RT) RIC 115 associated with a Service Management and Orchestration (SMO) Framework 105, or both). A CU 110 may communicate with one or more DUs 130 via respective midhaul links, such as an F1 interface. The DUs 130 may communicate with one or more RUs 140 via respective fronthaul links. The RUs 140 may communicate with respective UEs 104 via one or more radio frequency (RF) access links. In some implementations, the UE 104 may be simultaneously served by multiple RUs 140.

Each of the units, i.e., the CUs 110, the DUs 130, the RUs 140, as well as the Near-RT RICs 125, the Non-RT RICs 115, and the SMO Framework 105, may include one or more interfaces or be coupled to one or more interfaces configured to receive or to transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or to transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter, or a transceiver (such as an RF transceiver), configured to receive or to transmit signals, or both, over a wireless transmission medium to one or more of the other units.

The DU 130 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 140. In some aspects, the DU 130 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation, demodulation, or the like) depending, at least in part, on a functional split, such as those defined by 3GPP. In some aspects, the DU 130 may further host one or more low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 130, or with the control functions hosted by the CU 110.

Lower-layer functionality can be implemented by one or more RUs 140. In some deployments, an RU 140, controlled by a DU 130, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like), or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU(s) 140 can be implemented to handle over the air (OTA) communication with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU(s) 140 can be controlled by the corresponding DU 130. In some scenarios, this configuration can enable the DU(s) 130 and the CU 110 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

The SMO Framework 105 may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 105 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements that may be managed via an operations and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO Framework 105 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 190) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements can include, but are not limited to, CUs 110, DUs 130, RUs 140 and Near-RT RICs 125. In some implementations, the SMO Framework 105 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-cNB) 111, via an O1 interface. Additionally, in some implementations, the SMO Framework 105 can communicate directly with one or more RUs 140 via an O1 interface. The SMO Framework 105 also may include a Non-RT RIC 115 configured to support functionality of the SMO Framework 105.

The Non-RT RIC 115 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI)/machine learning (ML) (AI/ML) workflows including model training and updates, or policy-based guidance of applications/features in the Near-RT RIC 125. The Non-RT RIC 115 may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC 125. The Near-RT RIC 125 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 110, one or more DUs 130, or both, as well as an O-eNB, with the Near-RT RIC 125.

In some implementations, to generate AI/ML models to be deployed in the Near-RT RIC 125, the Non-RT RIC 115 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 125 and may be received at the SMO Framework 105 or the Non-RT RIC 115 from non-network data sources or from network functions. In some examples, the Non-RT RIC 115 or the Near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the Non-RT RIC 115 may monitor long-term trends and patterns for performance and employ AI/ML models to perform corrective actions through the SMO Framework 105 (such as reconfiguration via 01) or via creation of RAN management policies (such as A1 policies).

At least one of the CU 110, the DU 130, and the RU 140 may be referred to as a base station 102. Accordingly, a base station 102 may include one or more of the CU 110, the DU 130, and the RU 140 (each component indicated with dotted lines to signify that each component may or may not be included in the base station 102). The base station 102 provides an access point to the core network 120 for a UE 104. The base station 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station). The small cells include femtocells, picocells, and microcells. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG). The communication links between the RUs 140 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to an RU 140 and/or downlink (DL) (also referred to as forward link) transmissions from an RU 140 to a UE 104. The communication links may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base station 102/UEs 104 may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL). The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell).

The wireless communications system may further include a Wi-Fi AP 150 in communication with UEs 104 (also referred to as Wi-Fi stations (STAs)) via communication link 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the UEs 104/AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The base station 102 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate beamforming. The base station 102 may transmit a beamformed signal 182 to the UE 104 in one or more transmit directions. The UE 104 may receive the beamformed signal from the base station 102 in one or more receive directions. The UE 104 may also transmit a beamformed signal 184 to the base station 102 in one or more transmit directions. The base station 102 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 102/UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 102/UE 104. The transmit and receive directions for the base station 102 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.

The core network 120 may include an Access and Mobility Management Function (AMF) 161, a Session Management Function (SMF) 162, a User Plane Function (UPF) 163, a Unified Data Management (UDM) 164, one or more location servers 168, and other functional entities. The AMF 161 is the control node that processes the signaling between the UEs 104 and the core network 120. The AMF 161 supports registration management, connection management, mobility management, and other functions. The SMF 162 supports session management and other functions. The UPF 163 supports packet routing, packet forwarding, and other functions. The UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identification handling, access authorization, and subscription management. The one or more location servers 168 are illustrated as including a Gateway Mobile Location Center (GMLC) 165 and a Location Management Function (LMF) 166. However, generally, the one or more location servers 168 may include one or more location/positioning servers, which may include one or more of the GMLC 165, the LMF 166, a position determination entity (PDE), a serving mobile location center (SMLC), a mobile positioning center (MPC), or the like. The GMLC 165 and the LMF 166 support UE location services. The GMLC 165 provides an interface for clients/applications (e.g., emergency services) for accessing UE positioning information. The LMF 166 receives measurements and assistance information from the NG-RAN and the UE 104 via the AMF 161 to compute the position of the UE 104. The NG-RAN may utilize one or more positioning methods in order to determine the position of the UE 104. Positioning the UE 104 may involve signal measurements, a position estimate, and an optional velocity computation based on the measurements. The signal measurements may be made by the UE 104 and/or the base station 102 serving the UE 104. The signals measured may be based on one or more of a satellite positioning system (SPS) 170 (e.g., one or more of a Global Navigation Satellite System (GNSS), global position system (GPS), non-terrestrial network (NTN), or other satellite position/location system), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., barometric pressure sensor, motion sensor), NR enhanced cell ID (NR E-CID) methods, NR signals (e.g., multi-round trip time (Multi-RTT), DL angle-of-departure (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle-of-arrival (UL-AoA) positioning), and/or other systems/signals/sensors.

Referring again to FIG. 1, in some aspects, the base station 102 may include a BAT component 199. In some aspects, the BAT component 199 may be configured to receive, from a user equipment (UE), a burst arrival time (BAT) report including BAT information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session. In some aspects, the BAT component 199 may be configured to transmit, for a second network node, the BAT information associated with the at least one QoS flow. In some aspects, the BAT component 199 may be configured to receive, from a second network node, burst arrival time (BAT) information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session of a user equipment (UE). In some aspects, the BAT component 199 may be configured to configure, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG).

As described herein, a node (which may be referred to as a node, a network node, a network entity, or a wireless node) may include, be, or be included in (e.g., be a component of) a base station (e.g., any base station described herein), a UE (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, an integrated access and backhauling (IAB) node, a distributed unit (DU), a central unit (CU), a remote/radio unit (RU) (which may also be referred to as a remote radio unit (RRU)), and/or another processing entity configured to perform any of the techniques described herein. For example, a network node may be a UE. As another example, a network node may be a base station or network entity. As another example, a first network node may be configured to communicate with a second network node or a third network node. In one aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a UE. In another aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a base station. In yet other aspects of this example, the first, second, and third network nodes may be different relative to these examples. Similarly, reference to a UE, base station, apparatus, device, computing system, or the like may include disclosure of the UE, base station, apparatus, device, computing system, or the like being a network node. For example, disclosure that a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node. Consistent with this disclosure, once a specific example is broadened in accordance with this disclosure (e.g., a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node), the broader example of the narrower example may be interpreted in the reverse, but in a broad open-ended way. In the example above where a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node, the first network node may refer to a first UE, a first base station, a first apparatus, a first device, a first computing system, a first set of one or more one or more components, a first processing entity, or the like configured to receive the information; and the second network node may refer to a second UE, a second base station, a second apparatus, a second device, a second computing system, a second set of one or more components, a second processing entity, or the like.

As described herein, communication of information (e.g., any information, signal, or the like) may be described in various aspects using different terminology. Disclosure of one communication term includes disclosure of other communication terms. For example, a first network node may be described as being configured to transmit information to a second network node. In this example and consistent with this disclosure, disclosure that the first network node is configured to transmit information to the second network node includes disclosure that the first network node is configured to provide, send, output, communicate, or transmit information to the second network node. Similarly, in this example and consistent with this disclosure, disclosure that the first network node is configured to transmit information to the second network node includes disclosure that the second network node is configured to receive, obtain, or decode the information that is provided, sent, output, communicated, or transmitted by the first network node.

The controller/processor 359 can be associated with at least one memory 360 that stores program codes and data. The at least one memory 360 may be referred to as a computer-readable medium. In the UL, the controller/processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets. The controller/processor 359 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318Rx receives a signal through its respective antenna 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

The controller/processor 375 can be associated with at least one memory 376 that stores program codes and data. The at least one memory 376 may be referred to as a computer-readable medium. In the UL, the controller/processor 375 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets. The controller/processor 375 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

At least one of the TX processor 316, the RX processor 370, and the controller/processor 375 may be configured to perform aspects in connection with BAT component 199 of FIG. 1.

Wireless communication system may support various types of wireless communication. Some wireless communication may include XR traffic. In some aspects, XR traffic may refer to wireless communications for technologies such as virtual reality (VR), mixed reality (MR), and/or augmented reality (AR). VR may refer to technologies in which a user is immersed in a simulated experience that is similar or different from the real world. A user may interact with a VR system through a VR headset or a multi-projected environment that generates realistic images, sounds, and other sensations that simulate a user's physical presence in a virtual environment. MR may refer to technologies in which aspects of a virtual environment and a real environment are mixed. AR may refer to technologies in which objects residing in the real world are enhanced via computer-generated perceptual information, sometimes across multiple sensory modalities, such as visual, auditory, haptic, somatosensory, and/or olfactory. An AR system may incorporate a combination of real and virtual worlds, real-time interaction, and accurate three-dimensional registration of virtual objects and real objects. In an example, an AR system may overlay sensory information (e.g., images) onto a natural environment and/or mask real objects from the natural environment. XR traffic may include video data and/or audio data. XR traffic may be transmitted by a base station and received by a UE or the XR traffic may be transmitted by a UE and received by a base station.

XR traffic may arrive in periodic traffic bursts (“XR traffic bursts”). FIG. 4A illustrates an example diagram 450 showing a first XR flow 402 that includes a first XR traffic burst 404 and a second XR traffic burst 406. An XR traffic burst may vary in a number of packets per burst and/or a size of each packet in the burst. XR traffic bursts may arrive at non-integer periods (i.e., in a non-integer cycle). The periods may be different than an integer number of symbols, slots, etc. Arrival times of XR traffic may vary. For example, XR traffic bursts may arrive and be available for transmission at a time that is earlier or later than a time at which a UE (or a base station) expects the XR traffic bursts. The variability of the packet arrival relative to the period may be referred to as “jitter.” XR traffic may include multiple flows that arrive at a UE (or a network node such as a base station) concurrently with one another (or within a threshold period of time). As an example, the diagram 450 includes a second XR flow 408. The second XR flow 408 may have different characteristics than the first XR flow 402. For instance, the second XR flow 408 may have XR traffic bursts with different numbers of packets, different sizes of packets, etc. than the first XR flow 402. In an example, the first XR flow may include video data and the second XR flow may include audio data for the video data. In another example, the first XR flow may include intra-coded picture frames (I-frames) that include complete images and the second XR flow may include predicted picture frames (P-frames) that include changes from a previous image.

XR traffic may have an associated packet delay budget (PDB). If a packet does not arrive within the PDB, a UE (or a base station) may discard the packet. In an example, if a packet corresponding to a video frame of a video does not arrive at a UE within a PDB, the UE may discard the packet, as the video has advanced beyond the frame. XR traffic may be characterized by relatively high data rates and low latency. The latency in XR traffic may affect the user experience. For instance, XR traffic may have applications in cMBB and URLLC services.

In some wireless communication systems, a UE may report the average value of the arrival time of the first packet of the data burst for a QoS flow. The Burst Arrival Time (BAT) may be reported in the radio resource control (RRC) UE Assistance Information message, as an example. The BAT may be reported, e.g., (1) as reference time; or (2) as referenceSFN-AndSlot (reference system frame number and slot). As an example, when the BAT is reported as reference time, the indicated time may be in 10 ns units from an origin or reference time. For example, an indicated time may be: refDays*86400*1000*100000+refSeconds*1000*100000+refMilliSeconds*100000+refTenNanoSeconds. The refDays field specifies the sequential number of days (with day count starting at 0) from 00:00:00 on Gregorian calendar date 6 Jan. 1980 (e.g., using the start of GPS time as an origin or reference time). As an example, when the BAT is reported using a SFN and/or slot as a reference time (e.g., as referenceSFN-AndSlot), the BAT may refer to the UL timing of the closest system frame number (SFN) and slot of the primary cell (PCell) with the indicated number. To support XR in Dual Connectivity (NR-DC) scenarios, BAT reporting may be supported. Aspects provided herein may enable support of BAT reporting in XR DC.

FIG. 4B is a diagram 400 illustrating an example of a secondary cell group (SCG) and a master cell group (MCG), in accordance with various aspects of the present disclosure. As illustrated in FIG. 4B, the MCG 410 may include a PCell 412 and a set of SCells including a first SCell 414A, . . . and Nth SCell 414N. The SCG 420 may include a PSCell 422 and a set of SCells including a first SCell 424A, and any number of SCells up to an Nth SCell 424N.

FIG. 5 is a diagram 500 illustrating an example of communications between a first network node 504, a second network node 506, and a UE 502, in accordance with various aspects of the present disclosure. As illustrated in FIG. 5, the UE 502 may transmit a BAT report 508 to the first network node 504. The first network node 504 may extract, at 510, BAT information from the BAT report and forward the BAT information 512 to the second network node 506. Based on the BAT information 512, the second network node may configure MCG, SCG, CG, or DRX configuration 514 for the UE 502. For example, a DRX configuration may configure the UE to monitor for PDCCH transmissions in a discontinuous manner, e.g., using a sleep and wake cycle. A DRX cycle includes a DRX OFF duration and a DRX On duration. During DRX OFF durations, the UE does not monitor for PDCCH, and during the DRX ON durations, the UE monitors for PDCCH transmissions from the network. When the UE is in an RRC connected state, the DRX may also be referred to as connected node DRX (C-DRX). DRX conserves battery power at the UE. In a non-DRX mode, the UE monitors for PDCCH in each subframe to check whether there is downlink data available. In some aspects, scheduling mechanisms such as semi-persistent scheduling (SPS) or a configured grant (CG) may be used to provide (e.g., grant or allocate) the UE with periodic resources for UL or DL communication that can be used without a dynamic grant of resources. For example, the network may provide one or more CGs of recurring resources for uplink/downlink transmissions in radio resource control (RRC) signaling to the UE. For some types of configured grants, the UE may use the allocated resources based on the RRC configuration and without activation or control signaling from the network. In other types of configured grants, the UE may further receive an indication that the configured grant is activated or enabled for the UE to use, e.g., in a medium access control-control element (MAC-CE) or downlink control information (DCI). The UE may then use the recurring resources of the configured grant for uplink transmissions, e.g., until the UE receives signaling from the network that the configured grant is deactivated. The SPS or CG scheduling may be configured to accommodate the periodic traffic, multiple flows, jitter, latency, and reliability for the wireless traffic and may improve capacity and/or latency for such wireless communication.

In some aspects, the first network node 504 may be the SN and the second network node 506 may be the MN. In some aspects, the first network node 504 may be the MN and the second network node 506 may be the SN.

As an example, aspects provided herein may address various different scenarios related to XR DC. In a first example DC scenario, if signaling radio bearer (SRB) 3 (a direct SRB between the SN and the UE) is not present, the SN may not know the burst arrival time (BAT), and is not able to configure the UE in the SCG accordingly (e.g. connected mode discontinuous reception (CDRX), configured grants). In another example DC scenario, if SRB 3 is present, the UE can report the BAT to the secondary node (SN), but the master node (MN) may not know the BAT, and is not able to configure the UE in the MCG based on the BAT. SRB 3 is a type of signaling bearer to support signaling over split bearers when the UE is connected in a DC mode. SRB 3 may carry RRC signaling between the UE and a secondary node (SN).

Based on aspects provided herein, when there is no SRB 3 configured, the MN may signal the BAT to the SN. As an example, upon reception of a BAT report from the UE, the MN may forward BAT information to the SN. The BAT information (e.g., 512) may be transmitted to the SN in various ways, e.g., (1) the BAT may be extracted (e.g., at 510) from the RRC UE Assistance Information message (e.g., 508) and transmitted to the SN, or (2) the whole RRC UE Assistance Information message (e.g., 508) may be transmitted (e.g., forwarded) to the SN as an octet string, and the SN may extract the BAT. An Xn Application Protocol message, such as an S-NODE ADDITION REQUEST message or an S-NODE MODIFICATION REQUEST message may be used to carry the BAT information. If extracted by the MN, the BAT may be added to the S-NODE ADDITION REQUEST message or the S-NODE MODIFICATION REQUEST as an Xn-AP information element (IE) Burst Arrival Time. Examples are provided below:

S-NODE ADDITION REQUEST

> PDU Session Resources To Be Added List

>> PDU Session Resources To Be Added Item

>>> PDU Session Resource Setup Info - MN/SN terminated

>>>> QoS Flows To Be Setup List

>>>>> QoS Flows To Be Setup Item

>>>>> Burst Arrival Time

S-NODE MODIFICATION REQUEST

> PDU Session Resources To Be Added List

> PDU Session Resources To Be Modified List

>> PDU Session Resources To Be Modified Item

>>> PDU Session Resource Modification Info - MN/SN terminated

>>>> DRBs To Be Setup List

>>>> DRBs To Be Setup Item

>>>>> QoS Flows Mapped to DRB List

>>>>>> QoS Flows Mapped to DRB Item

>>>>>>> Burst Arrival Time

>>>> DRBs To Be Modified List

>>>> DRBs To Be Modified Item

>>>>> QoS Flows Mapped to DRB List

>>>>>> QoS Flows Mapped to DRB Item

>>>>>>> Burst Arrival Time

The IE PDU Session Resources To Be Added List may represent the PDU sessions that would be handled by the SN. The IE PDU Session Resources To Be Added Item may represent PDU session assigned to the SN, which may include PDU Session Resource Setup Info, which specifies whether the session is MN-terminated or SN-terminated. The IE QoS Flows To Be Setup List may include QoS flows that would be established within the PDU session. The IE QoS Flows To Be Setup Item may represent QoS flow(s) to be established for the session. The IE Burst Arrival Time, which indicates the expected arrival time of data bursts for the QoS flow, may be included as well.

The IE DRBs To Be Setup List may represent new DRBs that may be set up for the session. The IE DRBs To Be Setup Item may represent individual DRB(s) that will carry QoS flows. The IE QOS Flows Mapped to DRB List may represent QoS flows mapped to this DRB. The IE QOS Flows Mapped to DRB Item represents individual QoS flow(s) within the PRB. The IE DRBs To Be Modified List may represent DRBs that may be updated. The IE DRBs To Be Modified Item represents individual DRB(s) that may be updated.

Another example of IEs for reporting burst arrival time is provided below:

The IE ReferenceTime-r16 represents a precise timestamp that includes a number of days represented by refDays, number of seconds represented by refSeconds, number of milliseconds represented by refMilliSeconds, and number of ten nanoseconds represented by refTenNanoSeconds. The IE burstArrivalTime may indicate the burst arrival time either based on reference time or based on reference SFN and slot (which is represented by ReferenceSFN-AndSlot).

The IE burstArrivalTime that is based on either reference time or reference SFN and slot may be used for reporting BAT. If sent as an octet string, the RRC UE Assistance Information is added to the to the S-NODE ADDITION REQUEST message or the S-NODE MODIFICATION REQUEST as an Xn-AP IE “UE Assistance Information.” An example is provided below:

S-NODE ADDITION REQUEST

S-NODE MODIFICATION REQUEST

> UE Assistance Information

If burstArrivalTime is indicated as referenceSFN-AndSlot, it refers to the UL timing of the closest SFN and slot of the PCell with the indicated number. In asynchronous scenarios, the MN and the SN may not have the same timing. The SN may be aware of the difference between its timing and the MN's timing to adjust the BAT accordingly. Nodes can signal their offset between the International Atomic Time and their SFN0 start through the Xn-AP IE “SFN Offset” during Xn Setup and NG-RAN node configuration update procedures. If the MN did not signal its “SFN offset” to the SN during these procedures, the MN may include it along with the BAT. An IE SFN offset, which may contain time offset between an absolute time reference and the SFN0 start and calculated assuming that the SFN transmission started at the start reference, may be is added as an IE to the S-NODE ADDITION REQUEST message or the S-NODE MODIFICATION REQUEST. An example is provided below:

S-NODE ADDITION REQUEST

S-NODE MODIFICATION REQUEST

Based on aspects provided herein, when there is SRB 3 configured, the SN may signal the BAT to the MN. Upon reception of a BAT report from the UE, the SN can forward BAT information to the MN. The BAT information may be transmitted to the MN in two ways: (1) the BAT is extracted from the RRC UE Assistance Information message and transmitted to the MN, or (2) the whole RRC UE Assistance Information message is transmitted to the MN as an octet string, and the MN may extract the BAT.

To carry the BAT information, an Xn-AP message, such as the S-NODE MODIFICATION REQUIRED message, may be used. If extracted by the SN, the BAT is added to the S-NODE MODIFICATION REQUIRED message as an Xn-AP IE “Burst Arrival Time.” An example is provided below:

S-NODE MODIFICATION REQUIRED

> PDU Session Resources To Be Modified List

>> PDU Session Resources To Be Modified Item

>>> PDU Session Resource Modification Info - MN terminated

>>>> DRBs To Be Setup List

>>>> DRBs To Be Setup Item

>>>>> QoS Flows Mapped to DRB List

>>>>>> QoS Flows Mapped to DRB Item

>>>>>>> Burst Arrival Time

>>>> DRBs To Be Modified List

>>>> DRBs To Be Modified Item

>>>>> QoS Flows Mapped to DRB List

>>>>>> QoS Flows Mapped to DRB Item

>>>>>>> Burst Arrival Time

If sent as an octet string, the RRC UE Assistance Information is added to the S-NODE MODIFICATION REQUIRED message as an Xn-AP IE “UE assistance information.” An example is provided below:

S-NODE MODIFICATION REQUIRED

> UE Assistance Information

FIG. 6 is a flowchart 600 of a method of wireless communication. The method may be performed by a first network node (e.g., the base station 102, the first network node 504, the network entity 1060). Aspects provided herein may enable support of burst arrival time reporting in dual-connectivity scenarios, which improves efficiency of communication related to an extended reality session associated with a user equipment.

At 602, the first network node may receive, from a UE, a BAT report including BAT information associated with at least one QoS flow associated with an XR session. In some aspects, 602 may be performed by BAT component 199. As an example, the first network node 504 may receive, from a UE 502, a BAT report (e.g., 508) including BAT information associated with at least one QoS flow associated with an XR session.

At 604, the first network node may transmit, for a second network node, the BAT information associated with the at least one QoS flow. In some aspects, 604 may be performed by BAT component 199. As an example, the first network node 504 may transmit, for a second network node 506, the BAT information (e.g., 512) associated with the at least one QoS flow.

In some aspects, the first network node is a MN associated with the UE and the second network node is a SN associated with the UE, where a direct SRB between the SN and the UE is not present. In some aspects, the BAT report is included in radio resource control (RRC) UE assistance information, and where to transmit the BAT information, the first network node may: extract the BAT information from the RRC UE assistance information; and transmit, for the second network node, the BAT information. In some aspects, the BAT information is included in an SN addition request or an SN modification request as an information element representative of the BAT information. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may forward the RRC UE assistance information to the second network node as an Octet string. In some aspects, the Octet string is included in an SN addition request or an SN modification request as an information element representative of the RRC UE assistance information. In some aspects, to transmit the BAT information, the first network node may. In some aspects, the SN addition request or the SN modification request further includes a system frame number (SFN) offset.

In some aspects, the second network node is a MN associated with the UE and the first network node is a SN associated with the UE, where a direct SRB between the SN and the UE is present. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may extract the BAT information from the RRC UE assistance information; and transmit, for the second network node, the BAT information. In some aspects, the BAT information is included in an SN modification required message as an information element representative of the BAT information. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may forward the RRC UE assistance information to the second network node as an Octet string. In some aspects, the Octet string is included in an SN modification required message as an information element representative of the RRC UE assistance information. In some aspects, to transmit the BAT information, the first network node may transmit the BAT information in an SN modification required message.

FIG. 7 is a flowchart 700 of a method of wireless communication. The method may be performed by a first network node (e.g., the base station 102, the first network node 504, the network entity 1060). Aspects provided herein may enable support of burst arrival time reporting in dual-connectivity scenarios, which improves efficiency of communication related to an extended reality session associated with a user equipment.

At 702, the first network node may receive, from a UE, a BAT report including BAT information associated with at least one QoS flow associated with an XR session. In some aspects, 702 may be performed by BAT component 199. As an example, the first network node 504 may receive, from a UE 502, a BAT report (e.g., 508) including BAT information associated with at least one QoS flow associated with an XR session.

At 704, the first network node may transmit, for a second network node, the BAT information associated with the at least one QoS flow. In some aspects, 704 may be performed by BAT component 199. As an example, the first network node 504 may transmit, for a second network node 506, the BAT information (e.g., 512) associated with the at least one QoS flow.

In some aspects, the first network node is a MN associated with the UE and the second network node is a SN associated with the UE, where a direct SRB between the SN and the UE is not present. In some aspects, the BAT report is included in radio resource control (RRC) UE assistance information, and where to transmit the BAT information, the first network node may: extract the BAT information (e.g., at 703, which corresponds to 510 in FIG. 5) from the RRC UE assistance information; and transmit, for the second network node, the BAT information. In some aspects, the BAT information is included in an SN addition request or an SN modification request as an information element representative of the BAT information. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may forward the RRC UE assistance information to the second network node as an Octet string. In some aspects, the Octet string is included in an SN addition request or an SN modification request as an information element representative of the RRC UE assistance information. In some aspects, to transmit the BAT information, the first network node may. In some aspects, the SN addition request or the SN modification request further includes a system frame number (SFN) offset.

In some aspects, the second network node is a MN associated with the UE and the first network node is a SN associated with the UE, where a direct SRB between the SN and the UE is present. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may extract the BAT information from the RRC UE assistance information; and transmit, for the second network node, the BAT information. In some aspects, the BAT information is included in an SN modification required message as an information element representative of the BAT information. In some aspects, the BAT report is included in RRC UE assistance information, and where to transmit the BAT information, the first network node may forward the RRC UE assistance information to the second network node as an Octet string. In some aspects, the Octet string is included in an SN modification required message as an information element representative of the RRC UE assistance information. In some aspects, to transmit the BAT information, the first network node may transmit the BAT information in an SN modification required message.

FIG. 8 is a flowchart 800 of a method of wireless communication. The method may be performed by a first network node (e.g., the base station 102, the network node 506, the network entity 1060). Aspects provided herein may enable support of burst arrival time reporting in dual-connectivity scenarios, which improves efficiency of communication related to an extended reality session associated with a user equipment.

At 802, the first network node may receive, from a second network node, BAT information associated with at least one QoS flow associated with an XR session of a UE. In some aspects, 802 may be performed by BAT component 199. As an example, the first network node (e.g., 504) may receive, from a second network node (e.g., 502), BAT information (e.g., 512) associated with at least one QoS flow associated with an XR session of a UE (e.g., 512).

At 804, the first network node may configure, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG). In some aspects, 804 may be performed by BAT component 199. As an example, the first network node may configure, for the UE (e.g., 502) based on the BAT information (e.g., 512), a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG) (e.g., 514).

FIG. 9 is a flowchart 900 of a method of wireless communication. The method may be performed by a first network node (e.g., the base station 102, the network node 506, the network entity 1060). Aspects provided herein may enable support of burst arrival time reporting in dual-connectivity scenarios, which improves efficiency of communication related to an extended reality session associated with a user equipment.

At 902, the first network node may receive, from a second network node, BAT information associated with at least one QoS flow associated with an XR session of a UE. In some aspects, 902 may be performed by BAT component 199. As an example, the first network node (e.g., 504) may receive, from a second network node (e.g., 502), BAT information (e.g., 512) associated with at least one QoS flow associated with an XR session of a UE (e.g., 512).

At 904, the first network node may configure, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG). In some aspects, 904 may be performed by BAT component 199. As an example, the first network node may configure, for the UE (e.g., 502) based on the BAT information (e.g., 512), a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG) (e.g., 514). In some aspects, at 904A, the first network node may configure the MCG configuration for the UE. In some aspects, at 904B, the first network node may configure the SCG configuration for the UE.

In some aspects, the first network node is a MN associated with the UE and the second network node is a SN associated with the UE, where a direct SRB between the SN and the UE is present. In some aspects, the first network node may configure, for the UE based on the BAT information, the MCG configuration. In some aspects, the second network node is a MN associated with the UE and the first network node is a SN associated with the UE, where a direct SRB between the SN and the UE is not present. In some aspects, the first network entity may configure, for the UE based on the BAT information, the SCG configuration. In some aspects, to receive the BAT information, the first network node may receive the BAT information in an SN modification required message.

FIG. 10 is a diagram 1000 illustrating an example of a hardware implementation for a network entity 1060. In one example, the network entity 1060 may be within the core network 120. The network entity 1060 may include at least one network processor 1012. The network processor(s) 1012 may include on-chip memory 1012′. In some aspects, the network entity 1060 may further include additional memory modules 1014. The network entity 1060 communicates via the network interface 1080 directly (e.g., backhaul link) or indirectly (e.g., through a RIC) with the CU 1002. The on-chip memory 1012′ and the additional memory modules 1014 may each be considered a computer-readable medium/memory. Each computer-readable medium/memory may be non-transitory. The network processor(s) 1012 is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the corresponding processor(s) causes the processor(s) to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the processor(s) when executing software.

As discussed supra, the BAT component 199 may be configured to receive, from a user equipment (UE), a burst arrival time (BAT) report including BAT information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session. In some aspects, the BAT component 199 may be configured to transmit, for a second network node, the BAT information associated with the at least one QoS flow. In some aspects, the BAT component 199 may be configured to receive, from a second network node, burst arrival time (BAT) information associated with at least one quality of service (QOS) flow associated with an extended reality (XR) session of a user equipment (UE). In some aspects, the BAT component 199 may be configured to configure, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG). The component 199 may be further configured to perform any of the aspects described in connection with any of the flowcharts in FIGS. 6-9 and/or performed in the communication flow of FIG. 5. The component 199 may be within the network processor(s) 1012. The component 199 may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. When multiple processors are implemented, the multiple processors may perform the stated processes/algorithm individually or in combination. The network entity 1060 may include a variety of components configured for various functions. In some aspects, the network entity 1060 may include means for receiving, from a UE, a BAT report including BAT information associated with at least one QoS flow associated with an XR session. In some aspects, the network entity 1060 may include means for transmitting, for a second network node, the BAT information associated with the at least one QoS flow. In some aspects, the network entity 1060 may include means for extracting the BAT information from the RRC UE assistance information. In some aspects, the network entity 1060 may include means for transmitting, for the second network node, the BAT information. In some aspects, the network entity 1060 may include means for forwarding the RRC UE assistance information to the second network node as an Octet string. In some aspects, the network entity 1060 may include means for transmitting the BAT information in an SN addition request or an SN modification request. In some aspects, the network entity 1060 may include means for extracting the BAT information from the RRC UE assistance information. In some aspects, the network entity 1060 may include means for transmitting, for the second network node, the BAT information. In some aspects, the network entity 1060 may include means for forwarding the RRC UE assistance information to the second network node as an Octet string. In some aspects, the network entity 1060 may include means for transmitting the BAT information in an SN modification required message. In some aspects, the network entity 1060 may include means for receiving, from a second network node, BAT information associated with at least one QoS flow associated with an XR session of a UE. In some aspects, the network entity 1060 may include means for configuring, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG). In some aspects, the network entity 1060 may include means for configuring, for the UE based on the BAT information, the MCG configuration. In some aspects, the network entity 1060 may include means for configuring, for the UE based on the BAT information, the SCG configuration. In some aspects, the network entity 1060 may include means for receiving the BAT information in an SN modification required message. The network entity 1060 may further include means for performing any of the aspects described in connection with any of the flowcharts in FIGS. 6-9 and/or performed in the communication flow of FIG. 5. The means may be the component 199 of the network entity 1060 configured to perform the functions recited by the means. The means described above may be one or more of the components of the network entity 1060 configured to perform the functions recited by the means. In some aspects, the means may include one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. In some aspects, the network entity 1060 may include the TX Processor 316, the RX Processor 370, and the controller/processor 376. As such, in one configuration, the means may be the TX Processor 316, the RX Processor 370, and the controller/processor 376 configured to perform the functions recited by the means.

Aspect 1 is a method for wireless communication performed by a first network node, including: receiving, from a UE, a BAT report including BAT information associated with at least one QoS flow associated with an XR session; and transmitting, for a second network node, the BAT information associated with the at least one QoS flow.

Aspect 2 is the method of aspect 1, where the first network node is a MN associated with the UE and the second network node is a SN associated with the UE, where a direct SRB between the SN and the UE is not present.

Aspect 3 is the method of aspect 2, where the BAT report is included in RRC UE assistance information, and where transmitting the BAT information further includes: extracting the BAT information from the RRC UE assistance information; and transmitting, for the second network node, the BAT information.

Aspect 4 is the method of aspect 3, where the BAT information is included in an SN addition request or an SN modification request as an information element representative of the BAT information.

Aspect 5 is the method of aspect 2, where the BAT report is included in RRC UE assistance information, and where transmitting the BAT information further includes: forwarding the RRC UE assistance information to the second network node as an Octet string.

Aspect 6 is the method of aspect 5, where the Octet string is included in an SN addition request or an SN modification request as an information element representative of the RRC UE assistance information.

Aspect 7 is the method of any of aspects 2-6, where transmitting the BAT information further includes: transmitting the BAT information in an SN addition request or an SN modification request.

Aspect 8 is the method of aspect 7, where the SN addition request or the SN modification request further includes a system frame number (SFN) offset.

Aspect 9 is the method of aspect 1, where the second network node is a MN associated with the UE and the first network node is a SN associated with the UE, where a direct SRB between the SN and the UE is present.

Aspect 10 is the method of aspect 9, where the BAT report is included in RRC UE assistance information, and where transmitting the BAT information further includes extracting the BAT information from the RRC UE assistance information; and transmitting, for the second network node, the BAT information.

Aspect 11 is the method of aspect 10, where the BAT information is included in an SN modification required message as an information element representative of the BAT information.

Aspect 12 is the method of aspect 9, where the BAT report is included in RRC UE assistance information, and where transmitting the BAT information further includes: forwarding the RRC UE assistance information to the second network node as an Octet string.

Aspect 13 is the method of aspect 12, where the Octet string is included in an SN modification required message as an information element representative of the RRC UE assistance information.

Aspect 14 is the method of any of aspects 9-13, where transmitting the BAT information further includes: transmitting the BAT information in an SN modification required message.

Aspect 15 is a method for wireless communication performed by a first network node, including: receiving, from a second network node, BAT information associated with at least one QoS flow associated with an XR session of a UE; and configuring, for the UE based on the BAT information, a secondary cell group (SCG) configuration, a master cell group (MCG) configuration, a discontinuous reception (DRX) configuration, or a configured grant (CG).

Aspect 16 is the method of aspect 15, where the first network node is a MN associated with the UE and the second network node is a SN associated with the UE, where a direct SRB between the SN and the UE is present.

Aspect 17 is the method of aspect 16, further including: configuring, for the UE based on the BAT information, the MCG configuration.

Aspect 18 is the method of aspect 15, where the second network node is a MN associated with the UE and the first network node is a SN associated with the UE, where a direct SRB between the SN and the UE is not present.

Aspect 19 is the method of aspect 18, further including: configuring, for the UE based on the BAT information, the SCG configuration.

Aspect 20 is the method of any of aspects 18-19, where receiving the BAT information further includes: receiving the BAT information in an SN modification required message.

Aspect 21 is an apparatus for wireless communication at a device including at least one memory and at least one processor coupled to the at least one memory and, the at least one processor, individually or in any combination, based at least in part on information stored in the at least one memory, the at least one processor is configured to implement any of aspects 1 to 20.

Aspect 22 is the apparatus of aspect 21, further including one or more transceivers or one or more antennas coupled to the at least one processor.

Aspect 23 is an apparatus for wireless communication at a device including means for implementing any of aspects 1 to 20.

Aspect 24 is a computer-readable medium (e.g., a non-transitory computer-readable medium) storing computer executable code, where the code when executed by at least one processor causes the at least one processor to implement any of aspects 1 to 20.