Method and apparatus for using logical channel priority

Abstract

A user equipment (UE) configured to: in case a scheduling request (SR) is triggered by a logical channel (LCH) that includes LCH priority-adjusted data to be transmitted S210, determine priority of th

Description

BACKGROUND Field

[0001] Certain examples of the present disclosure relate to methods, apparatus and / or systems for using, determining or setting LCH priority. Further, various examples relate to determining whether or not LCH priority should be re-calculated, or whether or not the same, e.g. an already-calculated, priority should be used. In various examples, determination of priority in specific cases and / or under certain conditions is considered. In yet further examples, the priority is determined based on availability of data or delay-critical data for LCH(s) and / or based on a certain time, such as the time of new uplink data arrival, BSR triggering or MAC PDU assembly. Various examples also relate to the triggering of BSR in certain circumstances. Description of Related Art

[0002] The content of the following documents is referred to below and / or their content provides background information that the following disclosure should be considered in the context of: [1] 3GPPTS 38.321. [2] 3GPPRP-241771. Note: indicated version numbers are provided for illustrative purposes, other (including future) versions of these documents are considered also.

[0003] Wireless or mobile (cellular) communications networks in which a mobile terminal (e.g., user equipment (UE), such as a mobile handset) communicates via a radio link with a network of base stations (BSs), or other wireless access points (APs) or nodes, have undergone rapid development through a number of generations. The 3rd Generation Partnership Project (3GPP) design, specify and standardise technologies for mobile wireless communication networks. Fourth Generation (4G) and Fifth Generation (5G) systems (5GS) are now widely deployed, while beyond 5G (B5G) and 6G systems are being considered.

[0004] 3GPP standards for 4G systems include an Evolved Packet Core (EPC) and an Enhanced-UTRAN (E-UTRAN: an Enhanced Universal Terrestrial Radio Access Network). The E-UTRAN uses Long Term Evolution (LTE) radio technology. LTE is commonly used to refer to the whole system including both the EPC and the E-UTRAN, and LTE is used in this sense in the remainder of this document. LTE should also be taken to include LTE enhancements such as LTE Advanced and LTE Pro, which offer enhanced data rates compared to LTE.

[0005] In 5G systems a new air interface has been developed, which may be referred to as 5G New Radio (5G NR) or simply NR. NR is designed to support the wide variety of services and use case scenarios envisaged for 5G networks, though builds upon established LTE technologies B5G systems, such as 6G, are currently being considered and developed, and are expected to at least partly build on 5G systems.

[0006] New frameworks and architectures are being developed as part of 5G network (and beyond, such as 6G networks) in order to increase the range of functionality and use cases available through 5G networks. One area currently under development relates to logical channels.

[0007] Logical Channel Prioritization, or LCP, is a procedure carried out at the MAC layer of 5G NR, and used to determine the amount of data from each individual logical channel (LCH) which is then inserted into a given MAC PDU for uplink (UL) transmission. Transmission resources are limited, and LCP provides a balance between prioritizing high-priority data, and starving lower-priority data. LCP is currently (according to legacy, Rel-18 NR and earlier, systems) carried out in two rounds. 1 st and 2nd Rounds of LCP are shown in the excerpt from TS 38.321 below using bold text and underlined text, respectively. From TS 38.321 [1]: The MAC entity shall, when a new transmission is performed: 1> allocate resources to the logical channels as follows: 2> logical channels selected in clause 5.4.3.1.2 for the UL grant with Bj >0 are allocated resources in a decreasing priority order. If the PBR of a logical channel is set to infinity, the MAC entity shall allocate resources for all the data that is available for transmission on the logical channel before meeting the PBR of the lower priority logical channel(s); 2> decrement Bj by the total size of MAC SDUs served to logical channel j above; 2> if any resources remain, all the logical channels selected in clause 5,4,3,1.2 are served in a strict decreasing priority order (regardless of the value of Bj) until either the data for that logical channel or the UL grant is exhausted, whichever comes first. Logical channels configured with equal priority should be served equally.

[0008] Ongoing Rel-19 NR work includes continuation of XR (extended Reality) work, which poses new challenges due to its unique combination of high bit rates and low latency. The stringent requirements of XR in terms of delay, in particular, require enhancements to existing NR scheduling techniques including aforementioned LCP.

[0009] In the 3GPP RAN2#127 meeting (August 2024), RAN2 made the following agreements for scheduling enhancements pertaining to XR requirements: RAN2 to no longer consider the enhancement of the LCP restriction, as one of the candidate solutions for LCP enhancements in Rel-19 XR. FFS whether / how additional priority impacts intra-UE prioritization (can be discussed in stage-3)

[0010] Also, according to the revised Rel-19XRWorkltem Description (in 3GPPtdoc RP-241771, “Revised WID on XR (extended Reality) for NR Phase 3” [2]), and as shown by the underlined text below. RAN2 should specify the additional logical channel priority handling using delay / deadline information of packets: Specify Enhancements for support of UL scheduling to enable high XR capacity while meeting delay requirements / avoiding too late PDUs, as follows [RAN2]: - Specify additional Logical Channel priority handling using delav / deadline information of packets; - Specify enhanced DSR (Delay Status Report) reporting with multiple pairs of remaining time and buffer size for an LCG.

[0011] In the subsequent meeting (RAN2#127-bis meeting), RAN2 made the following agreements for LCP enhancements for Rel-19 XR: Agreements on LCP enhancements 1. As a baseline, additional LCH priority is applied for an LCH in both 1 st and 2nd Rounds of resource allocation procedure in LCP, as long as the LCH has delay-critical data available for transmission when starting the 1st Round. 2. FFS if we can still change the priority for the 2nd round to ensure fairness, but we need to consider tight timeline of LCP procedure and UE complexity. Companies can also check whether we can leave this to UE implementation 3. Introduce an independent per-LCH remaining time threshold for applying delay-critical priority. 4. We do not introduce any setting restrictions of this new remaining time threshold with relation to DSR triggering threshold. 5

[0012] And additionally, on the topic of terminology, the followingwas agreed: => For now, we will use “LCH priority-adjusted data”

[0013] Additionally, in the most recent meeting (RAN2#128, November 2024), the following was agreed: Agreements on LCP prioritization 1. As a baseline, the additional LCH priority is applied to both the first round and the second round of the LCP procedure. The UE does not fallback to the default LCH priority in the second round even if there is no more LCH priority-adjusted data after the first round. 2. As an optional capability, the UE can also support to fallback to default priority in the 2nd round of LCP. 10

[0014] In summary, 3GPP RAN2 agreed to introduce a new (referred to as “additional”) priority for a LCH which contains delay-critical data (referred to as “LCH priority-adjusted data”, to avoid the confusion with the term “delay-critical data” which is already used in legacy NR when describing DSR, or Delay Status Report. This new LCH priority may be configured in addition to legacy LCH priority, for certain LCHs where it 15 is applicable). A channel may be deemed to contain LCH priority-adjusted data, if the remainingtime before discard of any buffered PDCP SDL) in that LCH (as defined by a timer configured for this PDCP SDL)) goes below a LCH-specific configured threshold.

[0015] In legacy NR, LCH priority may be used in 1) resource allocation in LCP (as mentioned above), 2) BSR triggering (in some cases, a BSR is triggered only if data of higher priority arrives than priority of data already in the buffer), 3) truncated BSR LCG selection (when we do not have space to send the entire BSR), and / or 4) intra-UE prioritization. It is currently unclear whether each of these steps should trigger a recalculation of LCH priorities (i.e. determining whether each LCH contains delay-critical data at every given point in time where LCH priority needs to be used), and whether different steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of said MAC PDU) should use the same LCH priorities or not. SUMMARY

[0016] It is an aim of certain examples of the present disclosure to address, solve and / or mitigate, at least partly, at least one of the problems and / or disadvantages associated with the related art, for example at least one of the problems and / or disadvantages described herein. It is an aim of certain examples of the present disclosure to provide at least one advantage over the related art, for example at least one of the advantages described herein.

[0017] According to an aspect of the disclosure, there is provided a user equipment (UE) configured to: in case a scheduling request (SR) is triggered by at least one logical channel (LCH) that includes LCH priority-adjusted data to be transmitted, determine priority of the at least one LCH; and schedule transmission of the SR based on the determined priority.

[0018] According to various examples, intra-UE prioritization is configured at the UE; and wherein transmission of the SR overlaps in time with an uplink (UL) grant transmission.

[0019] According to various examples, the priority is determined as a priority of the at least one LCH at the time when the SR was triggered or a current priority of the at least one LCH.

[0020] According to various examples, the data includes the LCH priority-adjusted data.

[0021] According to another aspect of the present disclosure, there is provided a method of a user equipment (UE), the method comprising: in case a scheduling request (SR) is triggered by at least one logical channel (LCH) that includes LCH priority-adjusted data to be transmitted, determining priority of the at least one LCH; and scheduling transmission of the SR based on the determined priority.

[0022] According to various examples, the method of the above aspect is modified to include one or more features / operations to provide the feature(s) / operation(s) of a UE according to any of the examples given above.

[0023] According to another aspect of the disclosure, there is provided a user equipment (UE) configured to: trigger a buffer status report (BSR) in response to logical channel (LCH) priority-adjusted data being received by a medium access control (MAC) entity of the UE.

[0024] According to various examples, the BSR is triggered regardless of a priority of at least one LCH.

[0025] According to various examples, a priority associated with the BSR is determined according to a priority of a LCH included in the BSR.

[0026] According to various examples, the priority associated with the BSR is a priority of a BSR MAC control element (CE).

[0027] According to various examples, the priority of the BSR MAC CE is determined to be one of: a priority of the LCH including the LCH priority-adjusted data; or a priority of the highest-priority LCH included in the BSR.

[0028] According to various examples, the BSR is triggered prior to assembly of a MAC protocol data unit (PDU) includingthe BSR MAC CE.

[0029] According to various examples, the priority of the highest-priority LCH is a priority determined at the time of assembly of the MAC PDU including the BSR MAC CE or a priority determined at the time the BSR is triggered.

[0030] According to various examples, the priority of the BSR MAC CE is the priority of the LCH including the LCH priority-adjusted data if only part of the LCH priority-adjusted data is included in the MAC PDU.

[0031] According to various examples, the priority of the BSR MAC CE is the priority of the highest-priority LCH included in the BSR if the MAC PDU includes the LCH priority-adjusted data.

[0032] According to another aspect of the present disclosure, there is provided a method of a user equipment (UE), the method comprising: triggering a buffer status report (BSR) in response to logical channel (LCH) priority-adjusted data being received by a medium access control (MAC) entity of the UE.

[0033] According to various examples, the method of the above aspect is modified to include one or more features / operations to provide the feature(s) / operation(s) of a UE according to any of the examples given above.

[0034] According to another aspect of the present disclosure, there is provided a user equipment (UE) configured to: when assembling a medium access control (MAC) protocol data unit (PDU), prioritise a logical channel (LCH) including LCH-priority adjusted data over a MAC control element (CE); and control transmission of the MAC PDU.

[0035] According to various examples, the MAC CE is associated with a buffer status report (BSR), Delay Status Report (DSR) or Power Headroom Report (PHR).

[0036] According to various examples, the UE is configured to: determine a priority of a buffer status report (BSR) MAC CE as a priority of a LCH that triggered a BSR associated with the BSR MAC CE prior to assembly of the MAC PDU; wherein all data of the LCH cannot be included in the MAC PDU.

[0037] According to another aspect of the present disclosure, there is provided a method of a user equipment (UE), the method comprising: when assembling a medium access control (MAC) protocol data unit (PDU), prioritising a logical channel (LCH) including LCH-priority adjusted data over a MAC control element (CE); and controlling transmission of the MAC PDU.

[0038] According to various examples, the method of the above aspect is modified to include one or more features / operations to provide the feature(s) / operation(s) of a UE according to any of the examples given above.

[0039] According to another aspect of the present disclosure, there is provided a computer-readable storage medium comprising instructions which, when executed by one or more processors of an electronic device, cause the electronic device to perform a method according to anyone or more of the aspects or examples described above.

[0040] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Embodiments / examples of the present disclosure are further described hereinafter with reference to the accompanying drawings, in which: Figure 1 is a block diagram illustrating an example structure of an entity in accordance with various examples of the present disclosure. Figure 2 is a flow diagram illustrating a method in accordance with various examples of the present disclosure. Figure 3 is a flow diagram illustrating a method in accordance with various examples of the present disclosure. Figure 4 is a flow diagram illustrating a method in accordance with various examples of the present disclosure DETAILED DESCRIPTION

[0042] The following description of examples of the present disclosure, with reference to the accompanying drawings, is provided to assist in a comprehensive understanding of certain examples of the present disclosure. The description includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the examples described herein can be made without departing from the scope of the invention or disclosure.

[0043] The same or similar components may be designated by the same or similar reference numerals, although they may be illustrated in different drawings.

[0044] Detailed descriptions of techniques, structures, constructions, functions or processes known in the art may be omitted for clarity and conciseness, and to avoid obscuring the subject matter of the present disclosure.

[0045] The terms and words used herein are not limited to the bibliographical or standard meanings, but are merely used to enable a clear and consistent understanding of the disclosure.

[0046] Throughout the description of this specification, the words “comprise”, “include” and “contain” and variations of the words, for example “comprising” and “comprises”, means “including but not limited to”, and is not intended to (and does not) exclude other features, elements, components, integers, steps, processes, operations, functions, characteristics, properties and / or groups thereof.

[0047] Throughout the description of this specification, the singular form, for example “a”, “an” and “the”, encompasses the plural unless the context otherwise requires. For example, reference to “an object” includes reference to one or more of such objects.

[0048] Throughout the description, the expression “at least one of A, B and / or C” (or the like), the expression “and / or”, and the expression “one or more of A, B and / or C” (or the like) should be seen to separately include all possible combinations, for example: A, B, C, A and B, A and C, A and B and C.

[0049] Throughout the description of this specification, language in the general form of “Xfor Y” (where Y is some action, process, operation, function, activity or step and X is some means for carrying out that action, process, operation, function, activity or step) encompasses means X adapted, configured or arranged specifically, but not necessarily exclusively, to do Y.

[0050] Features, elements, components, integers, steps, processes, operations, functions, characteristics, properties and / or groups thereof described or disclosed in conjunction with a particular aspect, embodiment or example are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.

[0051] Certain examples of the present disclosure relate to methods, apparatus and / or systems for systems for using, determining or setting LCH priority. Further, various examples relate to determining whether or not LCH priority should be re-calculated, or whether or not the same, e.g. an already-calculated, priority should be used. In various examples, determination of priority in specific cases and / or under certain conditions is considered. In yet further examples, the priority is determined based on availability of data or delay-critical data for LCH(s) and / or based on a certain time, such as the time of new uplink data arrival, BSR triggering or MAC PDU assembly. Various examples also relate to the triggering of BSR in certain circumstances.

[0052] The following examples are applicable to, and use terminology associated with, 3GPP 5G. However, the skilled person will appreciate that the techniques disclosed herein are not limited to these examples or to 3GPP 5G, and may be applied in any suitable system or standard, for example one or more existing and / or future generation wireless communication systems or standards. The skilled person will appreciate that the techniques disclosed herein may be applied in any existing or future releases of 3GPP 5G NR or any other relevant standard. For example, the functionality of the various network entities and other features disclosed herein may be applied to corresponding or equivalent entities or features in other communication systems or standards. Corresponding or equivalent entities or features may be regarded as entities or features that perform the same or similar role, function, operation or purpose within the network. In particular, the following disclosure should be considered at least in relation to 6G also, which is expected to use at least part of the 5G architecture, or equivalent, and to which the present disclosure also relates.

[0053] A particular network entity may be implemented as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, and / or as a virtualised function instantiated on an appropriate platform, e.g. on a cloud infrastructure.

[0054] The skilled person will appreciate that the present disclosure is not limited to the specific examples disclosed herein. For example: • The techniques disclosed herein are not limited to 3GPP 5G, B5G or 6G. • One or more entities in the examples disclosed herein may be replaced with one or more alternative entities performing equivalent or corresponding functions, processes or operations. • One or more of the messages in the examples disclosed herein may be replaced with one or more alternative messages, signals or other type of information carriers that communicate equivalent or corresponding information. • One or more further elements, entities and / or messages may be added to the examples disclosed herein. • One or more non-essential elements, entities and / or messages may be omitted in certain examples. • The functions, processes or operations of a particular entity in one example may be divided between two or more separate entities in an alternative example. • The functions, processes or operations of two or more separate entities in one example may be performed by a single entity in an alternative example. • Information carried by a particular message in one example may be carried by two or more separate messages in an alternative example. • Information carried by two or more separate messages in one example may be carried by a single message in an alternative example. • The order in which operations are performed may be modified, if possible, in alternative examples. • The transmission of information between network entities is not limited to the specific form, type and / or order of messages described in relation to the examples disclosed herein.

[0055] Certain examples of the present disclosure may be provided in the form of an apparatus / device / network entity configured to perform one or more defined network functions and / or a method therefor. Such an apparatus / device / network entity may comprise one or more elements, for example one or more of receivers, transmitters, transceivers, processors, controllers, modules, units, and the like, each element configured to perform one or more corresponding processes, operations and / or method steps for implementing the techniques described herein. For example, an operation / function of X may be performed by a module configured to perform X (or an X-module). Certain examples of the present disclosure may be provided in the form of a system (e.g., a network) comprising one or more such apparatuses / devices / network entities, and / or a method therefor.

[0056] It will be appreciated that examples of the present disclosure may be realized in the form of hardware, software or a combination of hardware and software. Certain examples of the present disclosure may provide a computer program comprising instructions or code which, when executed, implement a method, system and / or apparatus in accordance with any aspect, example and / or embodiment disclosed herein. Certain embodiments of the present disclosure provide a machine-readable storage storing such a program.

[0057] A network or CN according to one or more of the examples disclosed herein may include one or more of a Network Data Analytics Function (NWDAF) entity, an Access and Mobility Management Function (AMF) entity, a Session Management Function (SMF) entity, a Network Slice Selection Function (NSSF) entity, a Network Repository Function (NRF) entity, Application Function (AF) entity, and an Operation and Maintenance (CAM) entity. The network may include one or more Service Consumers (including one or more of the entities mentioned above and / or one or more other entities) that receive analytics from NWDAF. The skilled person will appreciate that a network may omit one or more of the entities mentioned above and / or may comprise one or more additional entities.

[0058] As mentioned above, in legacy NR, LCH priority may be used in 1) resource allocation in LCP (as mentioned above), 2) BSR triggering (in some cases, a BSR is triggered only if data of higher priority arrives than priority of data already in the buffer), 3) truncated BSR LCG selection (when we do not have space to send the entire BSR), and / or 4) intra-UE prioritization. It is currently unclear whether each of these steps should trigger a re-calculation of LCH priorities (i.e. determining whether each LCH contains delay-critical data at every given point in time where LCH priority needs to be used), and whether different steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of said MAC PDU) should use the same LCH priorities or not.

[0059] For instance, for a LCH#1 configured with a new / adjusted LCH priority P_a and legacy LCH priority P_b, assume that a BSR is triggered by arrival of data in LCH#1 which uses new / adjusted priority P_a as there are SDUs among its data close to expiry. Now further assume that once related MAC PDU (protocol data unit or packet data unit) is assembled, all delay critical data from LCH#1 is put or expected to be put in this MAC PDU. Then, when it comes to intra-UE prioritization, and if the priority of LCH#1 were re-calculated for use in the intra-UE prioritization procedure, the same LCH#1 would now have a priority P_b which would be different (possibly lower) from P_a. This could result in this MAC PDU not being prioritized even though it contains what was considered an urgent BSR MAC CE, and urgent (delay-critical) data.

[0060] In another example, a BSR is triggered and LCH#1 uses new / adjusted priority P_a as it contains SDUs close to expiry. By the time MAC PDU assembly starts, data arrives into LCH#2 which has priority P_b1 >P_a (and this was not the case when BSR was triggered, where LCH#2 had a priority P_b<P_a). For LCH priority-adjusted data, intime delivery is important. However, most of the MAC CEs, e.g., BSR / DSR / PHR, etc., still (e.g. according to legacy NR) have higher absolute priorities over any of XR data, and those MAC CEs can use any type of uplink grants. This could make unexpected interruption during LCP and MAC PDU generation, resulting in LCH priority-adjusted data being delayed due to such MAC CEs. Therefore, there may be value in data prioritization over some less important / urgent MAC CEs. In the example, if it is wanted to prioritize BSR MAC CE over data or not (e.g. in legacy systems we would prioritize the BSR MAC CE, but for XR data we may wish to prioritize data), it is unclear whether to compare P_b and P_a, or P_b1 and P_a.

[0061] Therefore and as shown above, it is at present unclear whether a re-calculation of the new (additional) priority is needed, what its technical benefits would be, and how it would apply and to which steps of the uplink scheduling process. The present disclosure therefore provides examples, aspects, embodiments etc. which aim to cover the decision(s) on which priority (e.g. baseline / legacy, and / or new / additional / adjusted) to use for the various steps where LCH priority may be used, and / or on the potential link between priorities for related steps. That is, examples of the present disclosure aim to address the issues described above. Any of the examples described herein may be performed by or implemented in an entity such as a network function (e.g. any of those described herein), a UE, a NG-RAN or base station, a cell, CN or another suitable entity.

[0062] According to various examples of the present disclosure, each of the MAC procedures involving use of the additional priority of LCHs should or may trigger a re-calculation of LCH priorities (e.g. the UE re-checks whether each LCH contains LCH priority-adjusted data at every given point in time where LCH priority needs to be used).

[0063] According to various examples of the present disclosure, different, potentially related steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of the MAC PDU or prior to the MAC PDU assembly; BSR triggering and related MAC PDU assembly) should or may use the same LCH priorities

[0064] According to various examples of the present disclosure, when deciding whether or not to trigger the buffer status report (BSR), one or more legacy condition (e.g. UL data, for a logical channel which belongs to an LCG, becomes available to the MAC entity and this UL data belongs to a logical channel with higher priority than the priority of any logical channel containing available UL data which belong to any LCG) is used (or a condition to be introduced in ongoing or future releases is used) but the LCH priority is either the default (e.g. legacy) or adjusted priority depending on (e.g. based on, or according to) availability of delay-critical data (LCH priority-adjusted data) for each LCH (e.g. there being at least one LCH) at the time new UL data becomes available for transmission. In an example, the priority is determined (or identified, obtained, calculated, configured, set etc.), or newly determined, only for the LCH(s) where the data has arrived. For example, a UE is configured to: use one or more condition, such as one or more legacy conditions, when deciding whether to trigger BSR; and to set or configure LCH priority based on a time of UL data arrival (or, more generally, based on UL data) and / or based on availability of delay-critical data (or, more generally, based on delay-critical data). In a further example, the UE is configured to set or configure the LCH priority to / as a default priority (such as according to legacy procedures) or to adjusted priority depending on the availability of delay-critical data at the time of new UL data arrival.

[0065] In various examples of the present disclosure, when deciding (or determining, choosing, selecting, identifying etc.) whether to trigger a / the BSR, the legacy procedure (e.g. one or more condition or legacy condition) is modified so that any arrival (e.g. reception, obtaining, detection etc.) of priority-adjusted (e.g. delay-critical) data triggers a BSR, regardless of the priority (e.g. default or adjusted) of at least one LCH(s). For example, a UE is configured to trigger or perform (e.g. generate and / or send) a BSR based on receiving delay-critical data (or priority adjusted data) regardless of the priority of a LCH.

[0066] In various examples, when - in response to BSR being triggered either as part of (e.g. due to or based on) any one of the embodiments / examples / aspects / etc. disclosed herein or legacy behaviour - a BSR MAC CE is created (or, more generally, a message relating to BSR is created), a priority for such a BSR MAC CE is introduced (e.g. provided, defined, or assigned) for use in the MAC PDU assembly procedure. Here, said priority may be that of the logical channel that resulted in the most recent BSR trigger prior to MAC PDU assembly, in a case where said logical channel has data which cannot all be included in the MAC PDU. In various examples, in a case where all such data can be included in the MAC PDU, then the priority of the BSR MAC CE may be any of: the highest priority LCH included in the BSR where said priority may be determined at the time of MAC PDU assembly; or the highest priority LCH included in the BSR where said priority may be determined at the time of BSR triggering. In other words, according to various examples: if data from a LCH responsible for or linked with the most recent triggering of BSR prior to MAC PDU assembly cannot all be included in the MAC PDU then priority of the BSR MAC CE is the priority of said LCH (or linked to / determined based on that priority); else priority of the BSR MAC CE may be any one of: the highest priority LCH included in the BSR where said priority may be determined at the time of MAC PDU assembly; or the highest priority LCH included in the BSR where said priority may be determined at the time of BSR triggering.

[0067] In various examples, when a BSR is triggered but the UE currently has no UL grants, an SR (Scheduling Request) is triggered. By the time an SR is sent, and the UL grant is given to the UE, so that a MAC PDU may be assembled and a BSR MAC CE may finally be sent, a relatively significant time may have lapsed. Certain delay-critical data may have ‘expired’ and it may no longer be critical or necessary to send it. Therefore, a priority for a BSR MAC CE may also be different (lower in this example) than at the time when BSR was triggered, and it may be defined as that of highest-priority among LCHs whose status is being reported in the BSR MAC CE, calculated at the time of UL grant reception, any intra-UE prioritization procedure, or MAC PDU assembly.

[0068] In various examples, when, in response to BSR being triggered either as part of (e.g. due to or based on) any one of the embodiments / examples / aspects / etc. disclosed herein or legacy behaviour, a BSR MAC CE is created, a priority for such a BSR MAC CE is introduced (e.g. provided, defined, or assigned) for use in the MAC PDU assembly procedure. Here, said priority may be that of the logical channel that resulted in the most recent BSR trigger prior to MAC PDU assembly, and said logical channel may be that whose delay-critical data cannot all be included in the MAC PDU. In various examples, if all such delay-critical data can be included in the MAC PDU, then the priority of the BSR MAC CE may be any of: the highest priority LCH included in the BSR where said priority may be determined at the time of MAC PDU assembly; or the highest priority LCH included in the BSR where said priority may be determined at the time of BSR triggering. According to various examples: if delay-critical data from a LCH responsible for or linked with the most recent triggering of BSR prior to MAC PDU assembly cannot all be included in the MAC PDU then priority of the BSR MAC CE is the priority of said LCH (or linked to / determined based on that priority); else priority of the BSR MAC CE may be any one of: the highest priority LCH included in the BSR where said priority may be determined at the time of MAC PDU assembly; or the highest priority LCH included in the BSR where said priority may be determined at the time of BSR triggering.

[0069] Accordingly, in an example, a UE is configured to provide or configure a priority for a BSR MAC CE and for use in a MAC PDU assembly procedure, in response to BSR being triggered according to legacy behaviour or one of the examples disclosed herein; wherein the priority is configured as or determined to be priority of the logical channel that resulted in the most recent BSR trigger prior to the MAC CE being assembled. The logical channel may be one for which data or delay-critical data cannot all be included in the MAC PDU (e.g. as determined by the UE). If the data or the delay-critical data of the logical channel can be included in the MAC PDU, the UE configures the priority of the BSR MAC CE based on the priority of a LCH included in the BSR. Here, the UE may configure the priority as one of: the highest priority LCH included in the BSR where said priority may be determined at the time of MAC PDU assembly, or the highest priority LCH included in the BSR where said priority may be determined at the time of BSR triggering

[0070] In various examples, for MAC PDU assembly, the priority of a LCH during the associated LCP procedure is either the default (e.g. legacy) or adjusted priority, depending on (e.g. based on) availability of critical data at the time of MAC PDU assembly (e.g. configuration, generation, setting, etc.). In another example, for MAC PDU assembly which includes a BSR MAC CE, the priority of a LCH duringthe LCP procedure is either the default (e.g. legacy) or adjusted priority, depending on (e.g. based on) availability of critical data at the time of BSR triggering. In another example, for MAC PDU assembly which includes a DSR MAC CE, the priority of a LCH duringthe LCP procedure is either the default (e.g. legacy) or adjusted priority, depending on (e.g. based on) availability of critical data at the time of DSR triggering.

[0071] According to various examples of the present disclosure, the priorities of (or each priority of the) LCH(s) are determined (e.g. re-calculated) at any point (e.g. in time) where they need to be used (e.g. based on the use or determined use of the priorities). In another embodiment, the priorities of (or each priority of the) LCH(s) are determined (e.g. re-calculated) at the point of BSR triggering (or when BSR is triggered, or based on BSR triggering), and then may be used (e.g. as-is) for MAC PDU assembly and may be used for any intra-UE prioritization linked to transmission of said MAC PDU. For example, a UE is configured to re-calculate a priority of an LCH (or priorities for each of a plurality of LCHs) upon identifying a need to use said priority, such as identifying occurrence of a procedure (e.g. LCP procedure) which makes use of said priority.

[0072] In legacy systems, determining UL grant priority when intra-UE prioritization (needed when e.g. two uplink grant transmissions collide at least in part, such as when a configured uplink grant transmission overlaps in time with dynamically allocated uplink transmission or with another configured uplink grant transmission in the same serving cell, or in case a configured uplink grant transmissions or a dynamically allocated uplink transmission overlaps in time with a scheduling request transmission) is configured (i.e. in cases where the MAC entity is configured with Ich-basedPrioritization), may occur before or after the assembly of the MAC PDU(s) which will be sent using said grant(s). In legacy systems, for the cases of autonomousTx and HARQ retransmission, priority of an uplink grant is determined following the MAC PDU assembly; in all other cases, it is determined prior to the actual MAC PDU assembly and based on data available that can be multiplexed (and not necessarily data that will actually end up in the MAC PDU which will be sent using this grant).

[0073] In various examples, for the case of intra-UE prioritization linked to logical channel(s) that have LCH priority-adjusted data to be transmitted and which are multiplexed or can be multiplexed in MAC PDUs associated with the overlapping resources, and where the priority of the UL grant is determined after the MAC PDU(s) which will be carried by colliding grants are assembled, the priority of such a LCH used for the intra-UE prioritization is that from the start of the LCP procedure for said MAC PDU assembly (e.g. is the priority determined at the start of the LCP procedure for said MAC PDU assembly). In other words, in cases where MAC PDU is generated before the grant priorities have been determined for intra-UE prioritization, priority of the grant carrying this MAC PDU for the purposes of intra-UE prioritization may be determined as the highest priority amongst the LCHs multiplexed in MAC PDU where LCH priority is determined based on which of its SDU were multiplexed or are expected to be multiplexed in said MAC PDU. In another embodiment, the priority of such a LCH used for the intra-UE prioritization is the current LCH priority, i.e. the priority is re-calculated at the point of transmission. In this case, the priority of a MAC PDU may be determined at the time of its transmission as the highest priority amongst the LCHs multiplexed in MAC PDU where LCH priority of LCH is priority at the time of transmission.

[0074] In another example, for the case of intra-UE prioritization linked to logical channel(s) that have LCH priority-adjusted data to be transmitted and which are multiplexed or can be multiplexed in MAC PDUs associated with the overlapping resources, and where the priority of the UL grant is determined before the MAC PDU(s) which will be carried by colliding grants are assembled, the priority of such a LCH used for the intra-UE prioritization is that at the point priorities of the grant are being determined. In other words, the priority of such a LCH used for the intra-UE prioritization is that at the start of the intra-UE prioritization itself. In another embodiment, if the UE determines that at the point of MAC PDU assembly or MAC PDU transmission the data from the LCH which was used to determine the priority of the grant, the grant priorities are recalculated based on LCH priorities from the start of the LCP procedure for said MAC PDU assembly (e.g. is the priority determined at the start of the LCP procedure for said MAC PDU assembly). This could happen when, for instance, the make-up of the MAC PDU is different than what was estimated at the point of determining grant priorities (e.g. due to arrival of higher priority data; due to expiry of certain SDUs in certain channels; due to expiry of all SDUs in the LCH which was used to determine the priority of the grant). In other words, in cases where MAC PDU is generated after the grant priorities have been determined for intra-UE prioritization, priority of the grant carrying this MAC PDU for the purposes of intra-UE prioritization may be recalculated as the highest priority amongst the LCHs multiplexed in MAC PDU where LCH priority is determined based on which of its SDU were multiplexed in said MAC PDU. In another embodiment, the priority of such a LCH used for the intra-UE prioritization is the priority at the time of transmission, i.e. the priority is re-calculated at the point of transmission. In this case, the priority of a MAC PDU may be determined at the time of its transmission as the highest priority amongst the LCHs multiplexed in MAC PDU where LCH priority of LCH is priority at the time of transmission.

[0075] For example, in a case of intra-UE prioritization linked to LCHs that have priority-adjusted data to be transmitted and which are included in a MAC PDU(s) associated with overlapping resources, the priority of each LCH is set or configured as: the priority at the start of (e.g. determined or calculated at the start of) the LCP procedure for the MAC PDU(s) assembly, or the current LCH priority (e.g. re-calculated upon or at the time of intra-UE prioritization).

[0076] In various examples, for the case of intra-UE overlapping resources prioritization linked to scheduling request (SR) triggered by logical channel(s) that have LCH priority-adjusted data to be transmitted, the priority of the LCH which triggered the SR used for the intra-UE prioritization is that from the point in time when the SR was triggered (e.g. is the priority at the time when the scheduling request was triggered), or the current priority. In an example, for the former case, it may be more generally said that the priority of the LCH which triggered the SR used for the intra-UE prioritisation is based on the triggering of the SR.

[0077] Numbered Examples

[0078] There now follows a series of numbered Examples which are intended to illustrate various of the examples disclosed above (e.g. provide example implementations of embodiments disclosed above).

[0079] These numbered Examples show changes (shown underlined and / or with strikethrough text in the numbered Examples) that could be made to existing 3GPP Technical Specifications, includingTS 38.321 [1], It will be appreciated that any of the changes shown in one of the numbered Examples could be combined with any of the changes shown in one or more of the other numbered Examples (e.g. a mix-and-match approach may be taken when considering together all of the numbered Examples and changes shown therein). In other words, it will be understood that the present disclosure includes not only the numbered Examples and the changes shown for each numbered Example, but also all combinations of the different changes shown in the numbered Examples. Furthermore, it will be understood that the changes shown in each numbered Example may be considered in isolation, such that the present disclosure may be seen to teach examples including the changes only and not the existing parts of the corresponding 3GPP Technical Specification.

[0080] Example #1

[0081] Example #1 relates to using of adjusted priority for BSR triggering, and shows / includes a modification of TS 38.321 (v. 18.3.0): -------------------------38.321 V18.3.0------------------------- 5.4.5 Buffer Status Reporting The Buffer Status reporting (BSR) procedure is used to provide the serving gNB with information about UL data volume in the MAC entity. RRC configures the following parameters to control the BSR: - periodicBSR-Timer, retxBSR-Timer, logicalChannelSR-DelayTimerApplied, logicalChannelSR-DelayTimer, logicalChannelSR-Mask, logicalChannelGroup, logicalChannelGroupIAB-Ext, sdt-LogicalChannelSR-DelayTimer, additionalBS-TableAllowed. Each logical channel may be allocated to an LCG using the logicalChannelGroup. The maximum number of LCGs is eight except for lAB-MTs configured with logicalChannelGroupIAB-Ext, for which the maximum number of LCGs is 256. The MAC entity determines the amount of UL data available for a logical channel according to the data volume calculation procedure in TSs 38.322 [3] and 38.323 [4], A BSR shall be triggered if any of the following events occur for activated cell group: - UL data, for a logical channel which belongs to an LCG, becomes available to the MAC entity; and either - this UL data belongs to a logical channel with higher priority than the priority of any logical channel containing available UL data which belong to any LCG; or - none of the logical channels which belong to an LCG contains any available UL data. in which case the BSR is referred below to as 'Regular BSR'; - UL resources are allocated and number of padding bits is equal to or larger than the size of the Buffer Status Report MAC CE plus its subheader, in which case the BSR is referred below to as 'Padding BSR'; - retxBSR-Timer expires, and at least one of the logical channels which belong to an LCG contains UL data, in which case the BSR is referred below to as 'Regular BSR'; - periodicBSR-Timer expires, in which case the BSR is referred below to as 'Periodic BSR'. NOTE 1: When Regular BSR triggering events occur for multiple logical channels simultaneously, each logical channel triggers one separate Regular BSR. For Regular BSR, the MAC entity shall: 1> if the BSR is triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value true is configured by upper layers and SDT procedure is not ongoing according to clause 5.27: 2> start or restart the logicalChannelSR-DelayTimer. 1> else if BSR is triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value true is configured by upper layers and SDT procedure is ongoing according to clause 5.27: 2> start or restart logicalChannelSR-DelayTimer with the value as configured by the sdt-LogicalChannelSR-DelayTimer, if configured. 1> else: 2> if running, stop the logicalChannelSR-DelayTimer. For Regular and Periodic BSR, the MAC entity for which logicalChannelGroupIAB-Ext is not configured by upper layers shall: 1> if for at least one LCG configured with additionalBS-TableAlkrwed, the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is within the buffer sizes specified in Table 6.1.3.1-3: 2> report Refined Long BSR for all LCGs which have data available for transmission; 1> else: 2> if more than one LCG has data available for transmission when the MAC PDU containing the BSR is to be built: 3> report Long BSR for all LCGs which have data available for transmission. 2> else if one LCG has data available and is configured with additionalBS-TableAlkrwed and the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is greater than the largest buffer size specified in Table 6.1.3.1-3: 3> report Long BSR. 2> else: 3> report Short BSR. For Regular and Periodic BSR, the MAC entity for which logicalChannelGroupIAB-Ext is configured by upper layers shall: 1 >if more than one LCG has data available for transmission when the MAC PDU containing the BSR is to be built: 2> if the maximum LCG ID among the configured LCGs is 7 or lower: 3> report Long BSR for all LCGs which have data available for transmission. 2> else: 3> report Extended Long BSR for all LCGs which have data available for transmission. 1> else: 2> report Extended Short BSR. For Padding BSR, the MAC entity for which logicalChannelGroupIAB-Ext is not configured by upper layers shall: 1> if the number of padding bits is equal to or larger than the size of the Short BSR plus its subheader but smaller than the size of the Long BSR plus its subheader: 2> if more than one LCG has data available for transmission when the BSR is to be built: 3> if the number of padding bits is equal to the size of the Short BSR plus its subheader: 4> report Short Truncated BSR of the LCG with the highest priority logical channel with data available for transmission. 3> else: 4> report Long Truncated BSR of the LCG(s) with the logical channels having data available for transmission following a decreasing order of the highest priority logical channel (with or without data available for transmission) in each of these LCG(s), and in case of equal priority, in increasing order of LCGID. 2> else: 3> report Short BSR. 1> else if for at least one LCG configured with additionalBS-TahleAllowed, the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is within the buffer sizes specified in Table 6.1.3.1-3 and the number of padding bits is equal to or larger than the size of the Refined Long BSR plus its subheader: 2> report Refined Long BSR for all LCGs which have data available for transmission. 1> else if the number of padding bits is equal to or larger than the size of the Long BSR plus its subheader: 2> report Long BSR for all LCGs which have data available for transmission. For Padding BSR, the MAC entity for which logicalChannelGroupIAB-Ext is configured by upper layers shall: 1 >if the number of padding bits is equal to or larger than the size of the Extended Short BSR plus its subheader but smaller than the size of the Extended Long BSR plus its subheader: 2> if more than one LCG has data available for transmission when the BSR is to be built: 3> if the number of padding bits is smaller than the size of the Extended Long Truncated BSR with zero Buffer Size field plus its subheader: 4> report Extended Short Truncated BSR of the LCG with the highest priority logical channel with data available for transmission. 3> else: 4> report Extended Long Truncated BSR of the LCG(s) with the logical channels having data available for transmission following a decreasing order of the highest priority logical channel (with or without data available for transmission) in each of these LCG(s), and in case of equal priority, in increasing order of LCGID. 2> else: 3> report Extended Short BSR. 1> else if the number of padding bits is equal to or larger than the size of the Extended Long BSR plus its subheader: 2> report Extended Long BSR for all LCGs which have data available for transmission. For BSR triggered by retxBSR-Timer expiry, the MAC entity considers that the logical channel that triggered the BSR is the highest priority logical channel that has data available for transmission at the time the BSR is triggered. The MAC entity shall: 1> if the Buffer Status reporting procedure determines that at least one BSR has been triggered and not cancelled: 2> if UL-SCH resources are available for a new transmission and the UL-SCH resources can accommodate the BSR MAC CE plus its subheader as a result of logical channel prioritization: 3> instruct the Multiplexing and Assembly procedure to generate the BSR MAC CE(s) as defined in clause 6.1.3.1; 3> start or restartperiodicBSR-Timer except when all the generated BSRs are long or short Truncated or Extended long or short Truncated BSRs; 3> start or restart retxBSR-Timer. 2> if a Regular BSR has been triggered and logicalChannelSR-DelayTimer is not running: 3> if there is no UL-SCH resource available for a new transmission; or 3> if the MAC entity is configured with configured uplink grant(s) and the Regular BSR was triggered for a logical channel for which logicalChannelSR-Mask is set to false, or 3> if the UL-SCH resources available for a new transmission do not meet the LCP mapping restrictions (see clause 5.4.3.1) configured for the logical channel that triggered the BSR: 4> trigger a Scheduling Request. NOTE 2: UL-SCH resources are considered available if the MAC entity has been configured with, receives, or determines an uplink grant. If the MAC entity has determined at a given point in time that UL-SCH resources are available, this need not imply that UL-SCH resources are available for use at that point in time. A MAC PDU shall contain at most one BSR MAC CE, even when multiple events have triggered a BSR. The Regular BSR and the Periodic BSR shall have precedence over the padding BSR. The MAC entity shall restart retxBSR-Timer upon reception of a grant for transmission of new data on any UL-SCH. All triggered BSRs may be cancelled when the UL grant(s) can accommodate all pending data available for transmission but is not sufficient to additionally accommodate the BSR MAC CE plus its subheader. All BSRs triggered prior to MAC PDU assembly shall be cancelled when a MAC PDU is transmitted and this PDU includes a Long, Refined Long, Extended Long, Short, or Extended Short BSR MAC CE which contains buffer status up to (and including) the last event that triggered a BSR prior to the MAC PDU assembly. NOTE 3: MAC PDU assembly can happen at any point in time between uplink grant reception and actual transmission of the corresponding MAC PDU. BSR and SR can be triggered after the assembly of a MAC PDU which contains a BSR MAC CE, but before the transmission of this MAC PDU. In addition, BSR and SR can be triggered during MAC PDU assembly. NOTE 4: Void NOTE 5: If a HARQ process is configured with cg-RetransmissionTimer and if the BSR is already included in a MAC PDU for transmission on configured grant by this HARQ process, but not yet transmitted by lower layers, it is up to UE implementation how to handle the BSR content. NOTE 6: Logical channel priority used in the BSR procedure is either adjusted priority or default priority, depending on whether the logical channel contains any priority-adjusted data at the time of BSR triggering, or not. -------------------------38.321 V18.3.0-------------------------

[0082] Example #2

[0083] Example #2 relates to introducing or providing variable priority of a BSR MAC CE relative to logical channel data, and shows / includes a modification of TS 38.321 (v.18.3.0): -------------------------38.321 V18.3.0------------------------- 5.4.3.1.3 Allocation of resources Before the successful completion of the Random Access procedure initiated for DAPS handover, the target MAC entity shall not select the logical channel(s) corresponding to non-DAPS DRB(s) for the uplink grant received in a Random Access Response or the uplink grant for the transmission of the MSGA pay load. The source MAC entity shall select only the logical channel(s) corresponding to DAPS DRB(s) during DAPS handover. The MAC entity shall, when a new transmission is performed: 1> allocate resources to the logical channels as follows: 2> logical channels selected in clause 5.4.3.1.2 for the UL grant with Bj >0 are allocated resources in a decreasing priority order. If the PBR of a logical channel is set to infinity, the MAC entity shall allocate resources for all the data that is available for transmission on the logical channel before meeting the PBR of the lower priority logical channel(s); 2> decrement Bj by the total size of MAC SDUs served to logical channel j above; 2> if any resources remain, all the logical channels selected in clause 5.4.3.1.2 are served in a strict decreasing priority order (regardless of the value of Bj) until either the data for that logical channel or the UL grant is exhausted, whichever comes first. Logical channels configured with equal priority should be served equally. NOTE 1: The value of Bj can be negative. If the MAC entity is requested to simultaneously transmit multiple MAC PDUs, or if the MAC entity receives the multiple UL grants within one or more coinciding PDCCH occasions (i.e. on different Serving Cells), it is up to UE implementation in which order the grants are processed. The UE shall also follow the rules below during the scheduling procedures above: - the UE should not segment an RLC SDU (or partially transmitted SDU or retransmitted RLC PDU) if the whole SDU (or partially transmitted SDU or retransmitted RLC PDU) fits into the remaining resources of the associated MAC entity; - if the UE segments an RLC SDU from the logical channel, it shall maximize the size of the segment to fill the grant of the associated MAC entity as much as possible; - the UE should maximise the transmission of data; - if the MAC entity is given a UL grant size that is equal to or larger than 8 bytes (when eLCID is not used) or 10 bytes (when eLCID is used) while having data available and allowed (according to clause 5.4.3.1) for transmission, the MAC entity shall not transmit only padding BSR and / or padding. The MAC entity shall: 1> if the MAC entity is configured with enhancedSkipUplinkTxDynamic with value true and the grant indicated to the HARQ entity was addressed to a C-RNTI, or if the MAC entity is configured with enhancedSkipUplinkTxConfigured with value true and the grant indicated to the HARQ entity is a configured uplink grant: 2> if there is no UCI to be multiplexed on this PUSCH transmission as specified in TS 38.213 [6]; and 2> if there is no aperiodic CSI requested for this PUSCH transmission as specified in TS 38.212 [9]; and 2> if the MAC PDU includes zero MAC SDUs; and 2> if the MAC PDU includes only the periodic BSR and there is no data available for any LCG, or the MAC PDU includes only the padding BSR: 3> not generate a MAC PDU for the HARQ entity. 1> else if the MAC entity is configured with skipUplinkTxDynamic with value true and the grant indicated to the HARQ entity was addressed to a C-RNTI, or the grant indicated to the HARQ entity is a configured uplink grant: 2> if there is no aperiodic CSI requested for this PUSCH transmission as specified in TS 38.212 [9]; and 2> if the MAC PDU includes zero MAC SDUs; and 2> if the MAC PDU includes only the periodic BSR and there is no data available for any LCG, or the MAC PDU includes only the padding BSR: 3> not generate a MAC PDU for the HARQ entity. Logical channels shall be prioritised in accordance with the following order (highest priority listed first): - MAC CE for C-RNTI, or data from UL-CCCH; - MAC CE for (Enhanced) BFR, or MAC CE for Configured Grant Confirmation, or MAC CE for Multiple Entry Configured Grant Confirmation; - MAC CE for Sidelink Configured Grant Confirmation; - MAC CE for LBT failure; - MAC CE for SL LBT failure according to clause 5.31.2; - MAC CE for Timing Advance Report; - MAC CE for Delay Status Report; - MAC CE for SL-BSR prioritized according to clause 5.22.1.6; - MAC CE for SL-PRS Resource Request; - MAC CE for (Extended) BSR, with exception of BSR included for padding, when the related BSR is triggered by a logical channel whose data cannot all be included in the MAC PDU, and whose priority is higher than or equal to the highest priority of any logical channel with data available for transmission; - MAC CE for (Enhanced) Single Entry PHR, or MAC CE for (Enhanced) Multiple Entry PHR or MAC CE for Single Entry PHR with assumed PUSCH, or MAC CE for Multiple Entry PHR with assumed PUSCH, or MAC CE for Enhanced Single Entry PHR for multiple TRP or MAC CE for Enhanced Multiple Entry PHR for multiple TRP, or MAC CE for Enhanced Single Entry PHR for multiple TRP STx2P or MAC CE for Enhanced Multiple Entry PHR for multiple TRP STx2P; - MAC CE for Positioning Measurement Gap Activation / Deactivation Request; - MAC CE for the number of Desired Guard Symbols; - MAC CE for Case-6 Timing Request; - MAC CE for (Extended) Pre-emptive BSR; - MAC CE for SL-BSR, with exception of SL-BSR prioritized according to clause 5.22.1.6 and SL-BSR included for padding; - MAC CE for IAB-MT Recommended Beam Indication, or MAC CE for Desired IAB-MT PSD range, or MAC CE for Desired DL Tx Power Adjustment; - data from any Logical Channel, except data from UL-CCCH; - MAC CE for (Extended) BSR, with exception of BSR included for padding, when the related BSR is triggered by a logical channel whose data can all be included in the MAC PDU. or whose priority is lower than the highest priority of any logical channel with data available for transmission; - MAC CE for Recommended bit rate query; - MAC CE for BSR included for padding; - MAC CE for SL-BSR included for padding. NOTE 2: Prioritization among MAC CEs of same priority is up to UE implementation. The MAC entity shall prioritize any MAC CE listed in a higher order than 'data from any Logical Channel, except data from UL-CCCH' over NR sidelink transmission. -------------------------38.321 V18.3.0-------------------------

[0084] Example #3 Example #3 relates to BSR triggering being modified so that arrival of delay-critical data triggers BSR regardless of relative LCH priorities, and shows / includes a modification of TS 38.321 (v.18.3.0): -------------------------38.321 V18.3.0------------------------- 5.4.5 Buffer Status Reporting The Buffer Status reporting (BSR) procedure is used to provide the serving gNB with information about UL data volume in the MAC entity. RRC configures the following parameters to control the BSR: - periodicBSR-Timer, retxBSR-Timer, logicalChannelSR-DelayTimerApplied, logicalChannelSR-DelayTimer, logicalChannelSR-Mask, logicalChannelGroup, logicalChannelGroupIAB-Ext, sdt-LogicalChamelSR-DelayTimer, additionalBS-TableAllowed. Each logical channel may be allocated to an LCG using the logicalChannelGroup. The maximum number of LCGs is eight except for lAB-MTs configured with logicalChannelGroupIAB-Ext, for which the maximum number of LCGs is 256. The MAC entity determines the amount of UL data available for a logical channel according to the data volume calculation procedure in TSs 38.322 [3] and 38.323 [4], A BSR shall be triggered if any of the following events occur for activated cell group: - UL data, for a logical channel which belongs to an LCG, becomes available to the MAC entity; and either - this UL data belongs to a logical channel with higher priority than the priority of any logical channel containing available UL data which belong to any LCG; or - this UL data contains priority-adjusted data; or - none of the logical channels which belong to an LCG contains any available UL data. in which case the BSR is referred below to as 'Regular BSR'; - UL resources are allocated and number of padding bits is equal to or larger than the size of the Buffer Status Report MAC CE plus its subheader, in which case the BSR is referred below to as 'Padding BSR'; - retxBSR-Timer expires, and at least one of the logical channels which belong to an LCG contains UL data, in which case the BSR is referred below to as 'Regular BSR'; - periodicBSR-Timer expires, in which case the BSR is referred below to as 'Periodic BSR'. NOTE 1: When Regular BSR triggering events occur for multiple logical channels simultaneously, each logical channel triggers one separate Regular BSR. For Regular BSR, the MAC entity shall: 1> if the BSR is triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value true is configured by upper layers and SDT procedure is not ongoing according to clause 5.27: 2> start or restart the logicalChannelSR-DelayTimer. 1> else if BSR is triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value true is configured by upper layers and SDT procedure is ongoing according to clause 5.27: 2> start or restart logicalChannelSR-DelayTimer with the value as configured by the sdt-LogicalChannelSR-DelayTimer, if configured. 1> else: 2> if running, stop the logicalChannelSR-DelayTimer. For Regular and Periodic BSR, the MAC entity for which logicalChannelGroupIAB-Ext is not configured by upper layers shall: 1> if for at least one LCG configured with additionalBS-TableAlkrwed, the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is within the buffer sizes specified in Table 6.1.3.1-3: 2> report Refined Long BSR for all LCGs which have data available for transmission; 1> else: 2> if more than one LCG has data available for transmission when the MAC PDU containing the BSR is to be built: 3> report Long BSR for all LCGs which have data available for transmission. 2> else if one LCG has data available and is configured with additionalBS-TableAllowed and the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is greater than the largest buffer size specified in Table 6.1.3.1-3: 3> report Long BSR. 2> else: 3> report Short BSR. For Regular and Periodic BSR, the MAC entity for which logicalChannelGroupIAB-Ext is configured by upper layers shall: 1 >if more than one LCG has data available for transmission when the MAC PDU containing the BSR is to be built: 2> if the maximum LCG ID among the configured LCGs is 7 or lower: 3> report Long BSR for all LCGs which have data available for transmission. 2> else: 3> report Extended Long BSR for all LCGs which have data available for transmission. 1> else: 2> report Extended Short BSR. For Padding BSR, the MAC entity for which logicalChannelGroupIAB-Ext is not configured by upper layers shall: 1> if the number of padding bits is equal to or larger than the size of the Short BSR plus its subheader but smaller than the size of the Long BSR plus its subheader: 2> if more than one LCG has data available for transmission when the BSR is to be built: 3> if the number of padding bits is equal to the size of the Short BSR plus its subheader: 4> report Short Truncated BSR of the LCG with the highest priority logical channel with data available for transmission. 3> else: 4> report Long Truncated BSR of the LCG(s) with the logical channels having data available for transmission following a decreasing order of the highest priority logical channel (with or without data available for transmission) in each of these LCG(s), and in case of equal priority, in increasing order of LCGID. 2> else: 3> report Short BSR. 1> else if for at least one LCG configured with additionalBS-TahleAllcrwed, the amount of UL data available for transmission when the MAC PDU containing the BSR is to be built is within the buffer sizes specified in Table 6.1.3.1-3 and the number of padding bits is equal to or larger than the size of the Refined Long BSR plus its subheader: 2> report Refined Long BSR for all LCGs which have data available for transmission. 1> else if the number of padding bits is equal to or larger than the size of the Long BSR plus its subheader: 2> report Long BSR for all LCGs which have data available for transmission. For Padding BSR, the MAC entity for which logicalChannelGroupIAB-Ext is configured by upper layers shall: 1> if the number of padding bits is equal to or larger than the size of the Extended Short BSR plus its subheader but smaller than the size of the Extended Long BSR plus its subheader: 2> if more than one LCG has data available for transmission when the BSR is to be built: 3> if the number of padding bits is smaller than the size of the Extended Long Truncated BSR with zero Buffer Size field plus its subheader: 4> report Extended Short Truncated BSR of the LCG with the highest priority logical channel with data available for transmission. 3> else: 4> report Extended Long Truncated BSR of the LCG(s) with the logical channels having data available for transmission following a decreasing order of the highest priority logical channel (with or without data available for transmission) in each of these LCG(s), and in case of equal priority, in increasing order of LCGID. 2> else: 3> report Extended Short BSR. 1> else if the number of padding bits is equal to or larger than the size of the Extended Long BSR plus its subheader: 2> report Extended Long BSR for all LCGs which have data available for transmission. For BSR triggered by retxBSR-Timer expiry, the MAC entity considers that the logical channel that triggered the BSR is the highest priority logical channel that has data available for transmission at the time the BSR is triggered. The MAC entity shall: 1> if the Buffer Status reporting procedure determines that at least one BSR has been triggered and not cancelled: 2> if UL-SCH resources are available for a new transmission and the UL-SCH resources can accommodate the BSR MAC CE plus its subheader as a result of logical channel prioritization: 3> instruct the Multiplexing and Assembly procedure to generate the BSR MAC CE(s) as defined in clause 6.1.3.1; 3> start or restartperiodicBSR-Timer except when all the generated BSRs are long or short Truncated or Extended long or short Truncated BSRs; 3> start or restart retxBSR-Timer. 2> if a Regular BSR has been triggered and logicalChannelSR-DelayTimer is not running: 3> if there is no UL-SCH resource available for a new transmission; or 3> if the MAC entity is configured with configured uplink grant(s) and the Regular BSR was triggered for a logical channel for which logicalChannelSR-Mask is set to false, or 3> if the UL-SCH resources available for a new transmission do not meet the LCP mapping restrictions (see clause 5.4.3.1) configured for the logical channel that triggered the BSR: 4> trigger a Scheduling Request. NOTE 2: UL-SCH resources are considered available if the MAC entity has been configured with, receives, or determines an uplink grant. If the MAC entity has determined at a given point in time that UL-SCH resources are available, this need not imply that UL-SCH resources are available for use at that point in time. A MAC PDU shall contain at most one BSR MAC CE, even when multiple events have triggered a BSR. The Regular BSR and the Periodic BSR shall have precedence over the padding BSR. The MAC entity shall restart retxBSR-Timer upon reception of a grant for transmission of new data on any UL-SCH. All triggered BSRs may be cancelled when the UL grant(s) can accommodate all pending data available for transmission but is not sufficient to additionally accommodate the BSR MAC CE plus its subheader. All BSRs triggered prior to MAC PDU assembly shall be cancelled when a MAC PDU is transmitted and this PDU includes a Long, Refined Long, Extended Long, Short, or Extended Short BSR MAC CE which contains buffer status up to (and including) the last event that triggered a BSR prior to the MAC PDU assembly. NOTE 3: MAC PDU assembly can happen at any point in time between uplink grant reception and actual transmission of the corresponding MAC PDU. BSR and SR can be triggered after the assembly of a MAC PDU which contains a BSR MAC CE, but before the transmission of this MAC PDU. In addition, BSR and SR can be triggered during MAC PDU assembly. NOTE 4: Void NOTE 5: If a HARQ process is configured with cg-RetransmissionTimer and if the BSR is already included in a MAC PDU for transmission on configured grant by this HARQ process, but not yet transmitted by lower layers, it is up to UE implementation how to handle the BSR content. NOTE 6: Logical channel priority used in the BSR procedure is either adjusted priority or default priority, depending on whether the logical channel contains any priority-adjusted data at the time of BSR triggering, or not. -------------------------38.321 V18.3.0-------------------------

[0085] It will also be appreciated that the numbered examples may be combined with any of the other examples in the present disclosure.

[0086] Figure 1 is a block diagram of an exemplary apparatus, or network entity, that may be used in examples of the present disclosure. The skilled person will appreciate said entity may be implemented, for example, as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, and / or as a virtualised function instantiated on an appropriate platform, e.g. on a cloud infrastructure.

[0087] The entity 1000 comprises a processor (or controller) 1001, a transmitter 1003 and a receiver 1005. The receiver 1005 is configured for receiving one or more messages from one or more other network entities, for example as described above. The transmitter 1003 is configured for transmitting one or more messages to one or more other network entities, for example as described above. The processor 1001 is configured for performing one or more operations, for example according to the operations as described above. The processor 1001 may represent one processor or more than one processor. The entity 1000 may also comprise memory, the memory comprising or storing instructions which, when executed by the processor (or the one or more processor) individually or collectively, causes the entity 1000 to perform a method accordingto any of the examples disclosed herein.

[0088] Figure 2 illustrates a method according to various examples of the present disclosure. The method maybe performed by a UE.

[0089] In operation S210, in case a scheduling request (SR) is triggered by at least one logical channel (LCH) that includes LCH priority-adjusted data to be transmitted, the UE determines priority of the at least one LCH.

[0090] In operation S220, the UE schedules transmission of the SR based on the determined priority.

[0091] Figure 3 illustrates a method according to various examples of the present disclosure. The method maybe performed by a UE.

[0092] In operation S310, the UE triggers a buffer status report (BSR) in response to logical channel (LCH) priority-adjusted data being received by a medium access control (MAC) entity of the UE. For example, the BSR is triggered regardless of a priority of at least one LCH.

[0093] Figure 4 illustrates a method according to various examples of the present disclosure. The method maybe performed by a UE.

[0094] In operation S410, when assembling a medium access control (MAC) protocol data unit (PDU), the UE prioritises a logical channel (LCH) including LCH-priority adjusted data over a MAC control element (CE).

[0095] In operation S420, the UE controls transmission of the MAC PDU.

[0096] It will be appreciated that, in each example / embodiment / aspect etc. described above, one or more features or operations may be omitted, modified or moved (e.g., to change the order of the features or the operations), if desired and appropriate. Additionally, one or more features or operations from any example / embodiment may be combined with features or operations from any other example / embodiment. In particular, regardless of whether or not a pointer towards a combination of features / examples is found herein, the present disclosure should be considered to include all combinations of two or more of the embodiments, examples etc. disclosed herein, and all combinations of two or more of the features disclosed herein.

[0097] The techniques described herein may be implemented using any suitably configured apparatus and / or system. Such an apparatus and / or system may be configured to perform a method according to any aspect, embodiment or example disclosed herein. Such an apparatus may comprise one or more elements, for example one or more of receivers, transmitters, transceivers, processors, controllers, modules, units, and the like, each element configured to perform one or more corresponding processes, operations and / or method steps for implementing the techniques described herein. For example, an operation / function of X may be performed by a module configured to perform X (or an X-module). The one or more elements may be implemented in the form of hardware, software, or any combination of hardware and software.

[0098] It will be appreciated that examples of the present disclosure may be implemented in the form of hardware, software or any combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage, for example a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape or the like.

[0099] It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs comprising instructions that, when executed, implement certain examples of the present disclosure. Accordingly, certain examples provide a program comprising code for implementing a method, apparatus or system accordingto any example, embodiment and / or aspect disclosed herein, and / or a machine-readable storage storing such a program. Still further, such programs may be conveyed electronically via any medium, for example a communication signal carried over a wired or wireless connection.

[00100] While the present disclosure has been shown, illustrated and described with reference to certain examples, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the disclosure.

[00101] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference. Acronyms and Definitions (as may be used herein) 3GPP 3rd Generation Partnership Project 5G 5th Generation 5GC 5G Core 5QI 5G QoS Identifier 5GS 5G System 5GSM 5G System Session Management 5GMM 5G System Mobility Management AF Application Function Al Artificial Intelligence AIML Artificial Intelligence / Machine Learning AM Acknowledged Mode AMF Access and Mobility Management Function AS Application Server ASP Application Service Provider ATSSS AccessTrafficSteeringSwitching & Splitting AUSF Authentication Server Function BSR Buffer Status Report CDRX Connected Mode Discontinuous Reception CSI Channel Status Information DCAF Data Collection Application Function DNAI Data Network Access Identifier DNN Data Network Name DRB Data Radio Bearer DSR Delay Status Report eNB Evolved Node B EPS Evolved Packet System FQDN Fully Qualified Domain Name GBR Guaranteed Bit Rate GMLC Gateway Mobile Location Centre gNB Next generation Node B GPSI Generic Public Subscription Identifier IAB Integrated Access and Backhaul ID Identity / ldentifier lloT Industrial Internet of Things IMEI International Mobile Equipment Identities IP Internet Protocol l-SMF Intermediate SMF LCH Logical Channel LCP Logical Channel Prioritization LMF Location Management Function MA-PDU Multiple Access PDU MAC Medium Access Control ML Machine Learning MME Mobility Management Entity MN Master Node MNO Mobile Network Operator MPTCP MultiPath TCP MT Mobile Termination NAS Non-Access Stratum NEF Network Exposure Function NRF Network Repository Function NG-RAN Next Generation Radio Access Network NG-eNB Next Generation eNB NSA Non-Standalone NSSF Network Slice Selection Function NW Network NWDAF Network Data Analytics Function GAM Operations and Management OS Operating System PCF Policy Control Function PCC Policy and Charging Control PCO Protocol Configuration Options PDCP Packet Data Convergence Protocol PDU Protocol Data Unit PHR Power Headroom Report PMF Performance Measurement Function PRS Positioning Reference Signal PRU Positioning Reference Unit PSA PDU session anchor QFI QoS Flow Identifier (ID) QoE Quality of Experience QoS Quality of Service RACH Random Access Channel RAN Radio Access Network RAT Radio Access Technology RLC-AM Radio LinkControlAcknowledge Mode RLC-UM Radio Link Control Unacknowledge Mode RSD Route Selection Descriptor SA Standalone SBA Service-Based Architecture SBI Service-Based Interface SCEF Service Capability Exposure Function SCP Service-Based Communication Proxy SCTP Stream ControlTransmission Protocol SDAP Service Data Adaptation Protocol SDU Service Data Unit SIM Subscriber Identity Module SL Sidelink SM Session Management SMF Session Management Function SN Secondary Node S-NSSAI Single Network Slice Selection Assistance Information SRC Source SRS Sounding Reference Signal SSC Session and Service Continuity SUPI Subscription Permanent Identifier TAI TrackingArea Identity TE Terminal Equipment TM Transparent Mode TS Technical Specification UDM Unified Data Manager UDR Unified Data Repository UE User Equipment UL Uplink UM Unacknowledged Mode UP User Plane UPF User Plane Function URLLC Ultra-Reliable and Low-Latency Communication URSP UE Route Selection Policy XRM extended Reality (XR) and Media ANNEX TO THE DESCRIPTION 3GPP TSG-RAN WG2 Meeting #129 Athens, Greece, 17-21 February 2025 R2-25xxxxx Agenda item: 8.7.4.1 Source: Samsung Title: Outstanding issues on LCP enhancements for Rel-19 XR Document for: Discussion &Decision 1. Introduction In the RAN2#127-bis meeting (October 2024), RAN2 made the following agreements for LCP enhancements for Rel-19 XR: Agreements on LCP enhancements 5. As a baseline, additional LCH priority is applied for an LCH in both 1st and 2nd Rounds of resource allocation procedure in LCP, as long as the LCH has delay-critical data available for transmission when starting the 1st Round. 6. FFS if we can still change the priority for the 2nd round to ensure fairness, but we need to consider tight timeline of LCP procedure and UE complexity. Companies can also check whether we can leave this to UE implementation 7. Introduce an independent per-LCH remaining time threshold for applying delay-critical priority. 8. We do not introduce any setting restrictions of this new remaining time threshold with relation to DSR triggering threshold. And additionally, on the topic of terminology, in the same meeting the following was agreed: => For now, we will use “LCH priority-adjusted data” In the subsequent and most recent RAN2#128 meeting (November 2024), RAN2 additionally agreed the following: Agreements on LCP prioritization 3. As a baseline, the additional LCH priority is applied to both the first round and the second round of the LCP procedure. The UE does not fallback to the default LCH priority in the second round even if there is no more LCH priority-adjusted data after the first round. 4. As an optional capability, the UE can also support to fallback to default priority in the 2nd round of LCP. In this paper, we discuss the key remaining issues of the operations related with the additional LCH priority, and the impact of agreements made, especially of the optional support of fallback in 2nd round. We look at the use of the additional LCH priority MAC procedures other than LCP, as well as handling of other priority traffic e.g. SRBs in light of the additional LCH priority for XR traffic. 2. Discussion 2.1 Additional LCH Priority in Other Procedures: general considerations In legacy NR, LCH priority is used in 1) resource allocation in LCP (which is already being adapted to XR as the agreements above attest), 2) BSR triggering (in some cases, a BSR is triggered only if data of higher priority arrives than priority of data already in the buffer), 3) truncated BSR LCG selection (when we do not have space to send the entire BSR), and 4) intra-UE prioritization. Based on the existing RAN2 agreements, it is currently unclear whether each of these steps should trigger a recalculation of LCH priorities (i.e. determining whether each LCH contains LCH priority-adjusted data at every given point in time where LCH priority needs to be used), or whether different steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of the MAC PDU) should use the same LCH priorities or not. Observation 1: It is currently unclear whether each of the MAC procedures involving use of the priority of LCHs should trigger a re-calculation of LCH priorities (i.e. determining whether each LCH contains LCH priority-adjusted data at every given point in time where LCH priority needs to be used), or whether different, potentially related steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of the MAC PDU; BSR triggering and related MAC PDU assembly) should use the same LCH priorities. Observation 2: Agreement made at RAN#128 (stating that the UE can optionally also support fallback to default priority in the 2nd round of LCP) potentially point in the direction of a unified approach (= the approach where the UE re-checks whether each LCH contains LCH priority-adjusted data at every given point in time where LCH priority needs to be used). Based on the above, we propose: Proposal 1. R AN2 to agree that procedures such as BSR triggering and intra-UE prioritization shall also use the additional LCP priority. Proposal 2. RAN2 to agree one of the following options: A) Each of the MAC procedures involving use of the additional priority of LCHs should trigger a re-calculation of LCH priorities (i.e. the UE re-checks whether each LCH contains LCH priority-adjusted data at every given point in time where LCH priority needs to be used) B) Different, potentially related steps (e.g. MAC PDU assembly and related intra-UE prioritization at point of transmission of the MAC PDU; BSR triggering and related MAC PDU assembly) should use the same LCH priorities 2.2 The intra-UE prioritization case and the additional LCH Priority Turning our attention now specifically to intra-UE prioritization, and as a reminder, according to 38.300, "in case a configured uplink grant transmissions or a dynamically allocated uplink transmission overlaps in time with a scheduling request transmission, the UE prioritizes the transmission based on the comparison between the priority of the logical channel which triggered the scheduling request and the highest priority of the logical channels that have data to be transmitted and which are multiplexed or can be multiplexed in MAC PDU associated with the overlapping resource". Therefore, in this legacy intra-UE prioritization, when more than one UL grant(s) and / or SR(s) overlap in time domain, a priority-based comparison among the overlapped UL grant(s) and / or SR(s) is conducted to determine which UL grant or SR should be transmitted. The prioritybased comparison is based on legacy (default) LCH priority, i.e., the priority of UL grant is defined as the highest (legacy) priority of LCHs multiplexed in the corresponding MAC PDU, and the priority of SR is defined as the (legacy) priority of the LCH triggering the SR. What is different in the case of intra-UE prioritization linked to logical channels that have LCH priority-adjusted data to be transmitted and which are multiplexed or can be multiplexed in MAC PDUs associated with the overlapping resources, is the need to discuss whether the priority of such a LCH used for the intra-UE prioritization is that from the start of the LCP procedure which led to the assembly of this MAC PDU, or the current priority at the time of MAC PDU transmission i.e. RAN2 would need to discuss whether the UE should revert to legacy (default) priority immediately after LCP is completed, or not. An illustrative example would be where, for a LCH#1 configured with a new / adjusted LCH priority P_a and legacy LCH priority P_b, a BSR is triggered by arrival of data in LCH#1 which uses new / adjusted priority P_a as there are SDUs among its data close to expiry. Let us further assume that once related MAC PDU is assembled, all LCH priority-adjusted data data from LCH#1 is put in this MAC PDU. Then, when we come to intra-UE prioritization, and if we were to re-calculate the priority of LCH#1 for use in the intra-UE prioritization procedure, the same LCH#1 would now have a priority P_b which would be different (possibly lower) from P_a. This could result in this MAC PDU not being prioritized even though it contains what was considered an urgent BSR MAC CE, and urgent (LCH priority-adjusted data) data. (Similar considerations apply for the case of intra-UE overlapping resources prioritization linked to scheduling request triggered by logical channels that have LCH priority-adjusted data to be transmitted, RAN2 to discuss whether the priority of the LCH which triggered the SR used for the intra-UE prioritization is that from the point in time when the SR was triggered, or the current priority.) Observation 3: Not having a clear understanding on conditions for re-calculating of LCH priorities at time of intra-UE prioritization, could cause issues in cases where all of the LCH priority-adjusted data was inserted into the MAC PDU (and where as a result this MAC PDU may then get deprioritized if re-calculation was done). Based on the above discussion, we propose the following: Proposal 3. For the case of intra-UE prioritization linked to logical channels that have LCH priority-adjusted data to be transmitted and which are multiplexed or can be multiplexed in MAC PDUs associated with the overlapping resources, R AN2 to agree one of the two following options: A) Priority of a MAC PDU for the purposes of intra-UE prioritization is determined as the highest priority amongst the LCHs multiplexed in MAC PDU at the time when the MAC PDU was generated (LCH priority is determined based on which of its SDUs were actually multiplexed into the MAC PDU) B) Priority of a MAC PDU for the purposes of intra-UE prioritization is determined as the highest priority amongst the LCHs multiplexed in MAC PDU at the time when the MAC PDU is to be transmitted Proposal 4. For the case of intra-UE overlapping resources prioritization linked to scheduling request triggered by logical channels that have LCH priority-adjusted data to be transmitted, RAN2 to discuss whether the priority of the LCH which triggered the SR used for the intra-UE prioritization is that from the point in time when the SR was triggered, or the current priority at the time of transmission. 2.3 Data prioritization over comparatively less urgent MAC CEs We now turn our attention to the potential use-case of prioritization of data over MAC CEs, which for LCHs with priority-adjusted data, is potentially very relevant as the in-time delivery is important. So far, dedicated configured grant or resource separated by LCP have been introduced over multiple releases of NR to aid in-time delivery. In Rel-18, multiple CG occasions, DSR reporting and discard mechanism were introduced to support in-time delivery with higher resource efficiency. However, most of the MAC CEs, e.g., BSR / DSR / PHR, etc., still have higher absolute priorities over any of XR data, and those MAC CEs can use any type of uplink grants. This could make unexpected interruption during LCP and MAC PDU generation, resulting in LCH priority-adjusted data being delayed due to such MAC CEs. Therefore, we see value in data prioritization over some less important / urgent MAC CEs, and propose the following: Proposal 5. RAN2 to consider prioritizing LCH with LCH priority-adjusted data over comparatively less important / urgent MAC CEs. As an illustration of some additional underlying issues, and using the BSR MAC CE as an example, a BSR is triggered and LCH#1 uses new / adjusted priority P_a as it contains SDUs close to expiry. By the time MAC PDU assembly starts, data arrives into LCH#2 which has priority P_bl >P_a (and this was not the case when BSR was triggered, where LCH#2 had a priority P_b<P_a). If we now want to prioritize BSR MAC CE over data or not (in legacy systems we would prioritize the BSR MAC CE, but for XR data we may wish to prioritize data), it is unclear whether we should compare P_b and P_a, or P_bl and P_a. Observation 4: Re-calculating LCH priorities at time of MAC PDU assembly relative to priorities at the time of BSR triggering could cause issues in cases where we want to prioritize data over a BSR MAC CE. Proposal 6. Assuming RAN2 agrees to prioritizing LCH with LCH priority-adjusted data over BSR MAC CEs where beneficial, when determining the priority of the BSR MAC CE relative to data in order to compare it with the priority of the data, the priority should be that of the logical channel that resulted in the most recent BSR trigger prior to MAC PDU assembly, and whose data cannot all be included in the MAC PDU. 2.4 Handling of SRBs In the past meetings, certain submissions discussed the perceived impact of the additional LCH priority on timely transmission of signaling data. In our view, the handling of this case is best left to network implementation: Proposal 7. Handling of any concerns to do with XR traffic potentially delaying SRBs traffic is left to network implementation.

Claims

1. A user equipment (UE) configured to:in case a scheduling request (SR) is triggered by at least one logical channel (LCH) that includes LCH priority-adjusted data to be transmitted, determine priority of the at least one LCH; andschedule transmission of the SR based on the determined priority.

2. The UE of claim 1, wherein intra-UE prioritization is configured at the UE; and wherein transmission of the SR overlaps in time with an uplink (UL) granttransmission.

3. The UE of claim 1 or claim 2, wherein the priority is determined as a priority of the at least one LCH at the time when the SR was triggered or a current priority of the at least one LCH.

4. The UE of any one of the previous claims, wherein the data includes the LCH priority-adjusted data.

5. A user equipment (UE) configured to:trigger a buffer status report (BSR) in response to logical channel (LCH) priority-adjusted data being received by a medium access control (MAC) entity of the UE.

6. The UE of claim 5, wherein the BSR is triggered regardless of a priority of at least one LCH.

7. The UE of claim 5 or claim 6, wherein a priority associated with the BSR isdetermined according to a priority of a LCH included in the BSR.

8. The UE of claim 7, wherein the priority associated with the BSR is a priority of a BSR MAC control element (CE).

9. The UE of claim 8, wherein the priority of the BSR MAC CE is determined to be one of: a priority of the LCH including the LCH priority-adjusted data; ora priority of the highest-priority LCH included in the BSR.

10. The UE of claim 9, wherein the BSR is triggered prior to assembly of a MAC protocol data unit (PDU) including the BSR MAC CE.

11. The UE of claim 10, wherein the priority of the highest-priority LCH is a priority determined at the time of assembly of the MAC PDU including the BSR MAC CE or a priority determined at the time the BSR is triggered.

12. The UE of any one of claims 9 to 11, wherein the priority of the BSR MAC CE is the priority of the LCH including the LCH priority-adjusted data if only part of the LCH priority-adjusted data is included in the MAC PDU.

13. The UE of any one of claims 9 to 11, wherein the priority of the BSR MAC CE is the priority of the highest-priority LCH included in the BSR if the MAC PDU includes the LCH priority-adjusted data.

14. A user equipment (UE) configured to:when assembling a medium access control (MAC) protocol data unit (PDU), prioritise a logical channel (LCH) including LCH-priority adjusted data over a MAC control element (CE); andcontrol transmission of the MAC PDU.

15. The UE of claim 14, wherein the MAC CE is associated with a buffer status report (BSR), Delay Status Report (DSR) or Power Headroom Report (PHR).

16. The UE of claim 14, configured to:determine a priority of a buffer status report (BSR) MAC CE as a priority of a LCH that triggered a BSR associated with the BSR MAC CE prior to assembly of the MAC PDU;wherein all data of the LCH cannot be included in the MAC PDU.

17. A method of a user equipment (UE), the method comprising:in case a scheduling request (SR) is triggered by at least one logical channel (LCH) that includes LCH priority-adjusted data to be transmitted, determining priority of the at least one LCH; andscheduling transmission of the SR based on the determined priority.

18. A method of a user equipment (UE), the method comprising:triggering a buffer status report (BSR) in response to logical channel (LCH) priority-adjusted data being received by a medium access control (MAC) entity of the UE.

519. A method of a user equipment (UE), the method comprising:when assembling a medium access control (MAC) protocol data unit (PDU), prioritising a logical channel (LCH) including LCH-priority adjusted data over a MAC control element (CE); and10 controlling transmission of the MAC PDU.

20. A computer-readable storage medium comprising instructions which, when executed by one or more processors of an electronic device, cause the electronic device to perform a method according to any one of claims 17 to 19.

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