WO2019137182A1

WO2019137182A1 - Wireless communication system and related aspects

Info

Publication number: WO2019137182A1
Application number: PCT/CN2018/122598
Authority: WO
Inventors: Olivier Marco
Original assignee: Jrd Communication (Shenzhen) Ltd
Priority date: 2018-01-11
Filing date: 2018-12-21
Publication date: 2019-07-18
Also published as: CN111345078A; GB201800504D0; GB2570134A; CN111345078B

Abstract

Methods for triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication are disclosed. For example, when a medium access control (MAC) entity is determined to have new uplink data available for a first logical channel belonging to a logical channel group, if it is determined either that: the first logical channel with new uplink data has a higher priority than the priority of any other logical channels belonging to any logical channel group with available uplink data, and where the other logical channels are allowed to use at least one of the serving cells allowed for the first logical channel with the new uplink data; or that none of the other logical channels which belong to any logical channel group and which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data, a buffer status report is triggered.

Description

WIRELESS COMMUNICATION SYSTEM AND RELATED ASPECTS

Technical Field

Embodiments of the disclosed technology relate to a wireless communication system and to related aspects, in particular but not exclusively to a so-called New Radio (NR) or 5G wireless communications network and related network devices and methods for enabling a wireless communication between, for example, a User Equipment (UE) or mobile device to access via Radio Access Technology (RAT) or a Radio Access Network (RAN) wireless network services. Embodiments of the invention relate in particular but not exclusively to new radio wireless communications networks which implement 5G Packet Data Convergence Protocol (PDCP) packet duplication.

Background

Wireless communication systems, such as the third-generation (3G) of mobile telephone standards and technology are well known. Such 3G standards and technology have been developed by the Third Generation Partnership Project (3GPP) . The 3rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications. Communication systems and networks have developed towards a broadband and mobile system.

The 3rd Generation Partnership Project has developed the so-called Long Term Evolution (LTE) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN) , for a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB) . More recently, LTE is evolving further towards the so-called 5G or NR (new radio) systems where one or more cells are supported by a base station known as a gNB.

In NR, when PDCP packet duplication is activated, the PDCP transmitter creates duplicates of PDCP Protocol Data Units (PDUs) and transmits them on a duplicate link or leg, i.e. a different Radio Link Control (RLC) entity and associated logical channel (also referred to as “RLC bearer” ) . The PDCP receiver eliminates the duplicate packets thanks to the Sequence Number (SN) included in the PDCP PDUs. The use of PCDP packet duplication enhances reliability and reduces latency, and as such is suitable for use in Ultra Reliable Low Latency Communications (URLLC) radio bearers where it can provide reliability and reduced latency.

It can be used as well to provide enhanced reliability for Signalling Radio Bearers (SRBs) . In addition, PCDP packet duplication is also useful for non-URLLC Dedicated Radio Bearers (DRBs) , for instance at the time of handover (HO) .

Packet duplication can be pre-configured by Radio Resource Control (RRC) at a radio bearer level, by configuring a duplicate link or leg, in addition to the initial link or leg. Both are associated to the same radio bearer PDCP entity. Packet duplication is supported both in the downlink (DL) and uplink (UL) . For DRBs, PDCP packet duplication is supported for acknowledged mode (AM) and unacknowledged mode (UM) . It is also supported both for dual connectivity (DC) in which case there is one leg or link on each cell group, and carrier aggregation (CA) in which case each link or leg is mapped on different carrier (s) . In uplink (UL) it can be dynamically activated/deactivated by a Medium Access Control (MAC) Control Element (CE) (a “MAC CE” ) , on a per DRB basis.

Embodiments of the disclosed technology seek to solve at least some of the outstanding problems in this domain.

Summary

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

Some examples of embodiments of the disclosed technology relate to a method of triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the method comprising:

determining if a medium access control (MAC) entity has new uplink data available for a first logical channel belonging to a logical channel group;

and if so, if it is determined either that:

the first logical channel with new uplink data has a higher priority than the priority of any other logical channels belonging to any logical channel group with available uplink data, and where the other logical channels are allowed to use at least one of the serving cells allowed for the first logical channel with the new uplink data; or that none of the other logical channels which belong to any logical channel group and which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data,

triggering a buffer status report.

In some examples of embodiments of the disclosed technology, the buffer status report is triggered if it is determined that: the new 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, and which is allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data ; or none of the logical channels which belong to an LCG and which are allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data contains any available UL data.

In some examples of embodiments of the disclosed technology, the method of triggering of the buffer status report is configurable in the wireless communications network by radio resource control.

In some examples of embodiments of the disclosed technology, the radio resource control configures the wireless network to implement a method of triggering the buffer status report either explicitly when logical channels or dedicated radio bearer/packet data convergence protocol is being configured in the network or implicitly when logical channels are configured which correspond to duplicated dedicated radio bearers.

In some examples of embodiments of the disclosed technology, the method is implemented only for one or more specific logical channel groups in the wireless communications network.

determining if a medium access control entity has new uplink data available for a logical channel belonging to a logical channel group;

and if so, if it is determined either that:

the new uplink data belongs to a logical channel with a higher priority than the priority of any logical channel containing available uplink data which belong to any logical channel group; or

no other logical channels which belong to any logical channel group contain any available up link data; or

the new uplink data belongs to a logical channel configured for fast buffer status report triggering,

triggering a buffer status report.

In some examples of embodiments of the disclosed technology, the buffer status report triggering is configured by radio resource control on a logical channel basis or on a logical channel used by a dedicated radio bearer basis.

In some examples of embodiments of the disclosed technology, the step of triggering the buffer status report further requires the new uplink data to belong to a logical channel which does not contain already available data.

Some examples of embodiments of the disclosed technology relate to a wireless network configured operate using a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication and the wireless network is capable of activating down link packet duplication, the network further comprising means to pre-configuring a reordering timer for use when a down link duplication is activated as part of the packet data convergence protocol configuration of the wireless network.

In some examples of embodiments of the disclosed technology, the network is configured to pre-configure a re-ordering timer if activation and/or deactivation of at least down link packet duplication is detected by using a MAC CE.

In some examples of embodiments of the disclosed technology, the network is configured to pre-configure a re-ordering timer if activation and/or deactivation of uplink packet duplication is detected by using a MAC CE.

In some examples of embodiments of the disclosed technology, the network is configured to consider whenever uplink activation is detected that down link packet duplication is activated.

In some examples of embodiments of the disclosed technology, the network is configured by radio resource control on a radio bearer basis to consider whenever uplink activation is detected that down link packet duplication is activated.

In some examples of embodiments of the disclosed technology, the network is configured to consider whenever data for a radio bearer is received on a second link after being received on a first link that down link duplication is activated.

In some examples of embodiments of the disclosed technology, the network is configured to consider down link duplication is deactivated whenever data for a radio bearer is received on only one link during a predetermined interval of time.

In some examples of embodiments of the disclosed technology, the wireless network includes at least one node at which a PDCP entity is located which is configured to adapt the reordering timer.

In some examples of embodiments of the disclosed technology, packet duplication is activated by a MAC CE from either a master node (MN) or a secondary node (SN) of the wireless network and the receiving PDCP entity is located either at the master node or the secondary node, and wherein, whenever a master or secondary node determines to activate and/or deactivate an uplink duplication, an indication of the decision is communicated to the other of the master or secondary node at which the PDCP entity is located.

In some examples of embodiments of the disclosed technology, an indication of the decision is communicated using Xn/X2 signalling to the other of the master or secondary node at which the PDCP entity is located to enable the node holding the PCDP entity to adapt the reordering timer.

In some examples of embodiments of the disclosed technology, where packet duplication is implemented by duplicating packets and sending them along different logical channels along at least one or more or all links or legs in the wireless network.

In some examples of embodiments of the disclosed technology, the wireless communications network comprises a Radio Access Network (RAN) , for example, a New Radio/5G radio access network.

In some examples of embodiments of the disclosed technology, provide a base station for use in a wireless network according to an embodiment of the disclosed technology.

Some examples of embodiments of the disclosed technology relate to a non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform any method embodiments of the disclosed technology.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

One or more or all features of examples of embodiments of the disclosed technology as described herein or in the accompanying claims may be combined with one or more or all features of other examples of embodiments of the disclosed technology as described herein or in the accompanying claims in any manner apparent to one of ordinary skill in the art.

Brief description of the drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. Like reference numerals have been included in the respective drawings to ease understanding.

Figure 1 shows schematically how PDCP packet duplication with carrier aggregation is configured for a radio bearer;

Figure 2A shows schematically a radio bearer not configured for PDCP packet duplication;

Figure 2B shows schematically a radio bearer which is configured for PDCP packet duplication over two LCHs;

Figure 3 shows schematically how downlink packet data control protocol (DL PDCP) reordering window is implemented.

Detailed description of the preferred embodiments

Those skilled in the art will recognise and appreciate that the specifics of the examples described are merely illustrative of some embodiments and that the teachings set forth herein are applicable in a variety of alternative settings.

Embodiments of the technology disclosed herein relate to resolving issues packet duplication related to the operation of NR/LTE 5G proposed networks.

Some embodiments of the disclosed technology relate to providing an enhanced Buffer Status Report (BSR) operation for duplication in carrier aggregation (CA) (MAC layer) . Whilst no specific BSR change is needed for a basic packet duplication operation in case of duplication in CA, with existing BSR solution, a BSR may not always be triggered upon the arrival of new data when CA duplication is activated, whereas a BSR would have been triggered if the CA packet duplication was not activated. This would degrade the latency of the radio bearer when duplication is activated, contrary to one of the expected goal of packet duplication. Some embodiments propose a BSR trigger operation which removes any degraded performance if packet duplication is activated.

Some other embodiments of the disclosed technology relate to providing an enhanced downlink (DL) Physical Dedicated Control Channel (PDCP) duplication operation (PDCP layer) . For DL, it is assumed that the network (NW) can configure and activate/deactivate the duplication operation whenever needed, without the need to inform the user equipment (UE) , and without impact on UE PDCP receive operation (as reordering and duplicate removal is already supported as part of normal PDCP operation in NR) . However, it is likely that when DL duplication is used, a longer reordering timer is needed to take into account the possible delay between both legs. The longer reordering timer should be used only when DL duplication is activated, since otherwise it would degrade the latency of the RB whenever PDCP COUNT gaps occur. Some embodiments propose to pre-configure a reordering timer to be used when DL duplication is activated. Some embodiments propose several ways to detect when DL duplication is activated.

Enhanced BSR operation for duplication in CA (MAC layer)

Consider a 5G new radio network (NW) in which the NW has preconfigured two logical channels (LCHs) (one channel for the initial link or leg and one for the duplicated link or leg) by radio resource control (RRC) configuration (see Figure 1 for example of the accompanying drawings for a schematic illustration of how PDCP packet duplication with CA may be implemented in a NR network) . The UE is ordered to activate/deactivate UL duplication dynamically by using a MAC CE. If the NW configures the same priority for both LCHs, given both LCHs refers to the same bearer, activating CA duplication may result in a degradation in latency that would not occur if duplication was not activated. For example, the rate of the data flow on the duplicated leg or link may be reduced, possibly to the extent that data may become stuck on the duplicated leg (due, for example, to a temporary blockage of the duplicated leg or link) . In such a situation, the arrival of new data for the radio bearer does not trigger a regular BSR even if the initial leg or link is empty (i.e. has no congestion) . The NW is aware of the arrival of new data only when it eventually receives either a periodic BSR or a padding BSR which may not be until several ms later.

Accordingly, activating a duplicate leg can affect the triggering of a BSR upon the arrival of new data and may even prevent a BSR triggering in situations where the BSR would have been triggered if the duplicated leg was not activated with the result being a degradation in the latency of the radio bearer. To avoid this the NW could pre-configure the duplicated LCH with a lower priority than the initial LCH. With such configuration, the radio bearer does experience a degradation in latency when packet duplication is activated compared to when it is not activated, since even if an event causes a blockage which results in data packets being stuck on the duplicated leg, such data would be of lower priority than the data arriving on the initial leg. This would then not prevent BSR triggering, i.e. the BSR triggering for the initial leg is not impacted by the activation of the duplicated leg. However, if instead some data is stuck in the original LCH this would prevent the new UL data arrival in the duplicated LCH triggering a BSR. To resolve this issue, instead the duplicated LCH should be pre-configured with a higher priority with the initial LCH.

Accordingly, in the art prior art, when CA duplication is activated for a RB, a regular BSR might not be triggered upon new UL data arrival for that RB whenever data for this RB is stuck in one leg, even if data is not stuck on the other leg, which would degrade latency of the RB.

In LTE Rel-8 (also reused in NR) , a regular BSR is triggered when there is new UL data available for a higher priority LCH, compared to the priority of LCH already containing available UL data (within a MAC entity) . This principle enables to limit BSR overhead, by triggering a regular BSR only upon limited cases. When the condition of new UL data availability is not satisfied (UL data already present with same or higher priority) , the periodic BSR is used to inform the NW scheduler about the UE buffer status. This required the NW scheduler however to be aware of existing higher or equal priority data so that it would first schedule resources for this existing data. Whilst a UE could be configured to trigger a BSR even in case on the UL new data is received when there is already data buffered with same priority, if the solution is left to UE implementation, some UEs may do it, some not, and the NW scheduler will not have consistent information across UEs. Optimally reliable BSR triggering is only required for packet duplication when LCHs are mapped on different carriers. If there is already data for a LCH and new data arrives for this LCH, triggering BSR may add a lot of overhead, and accordingly a periodic BSR can be used instead. However, if the UE is allowed to send BSR in that case, periodic BSR becomes useless.

Some embodiments of the disclosed technology seek address such situations by ensuring BSR is always appropriately triggered to reduce the likelihood of latency issues increasing when packet duplication is activated by proposing a compromise between the legacy BSR design (from LTE R8 etc. ) and the serving cell/component carrier (CC) restrictions introduced for packet duplication in CA.

Enhanced DL PDCP duplication operation (PDCP layer)

Another issue which can arise when PDCP layer packet duplication is implemented is that UE is not currently aware when DL duplication is used or not and if the NW wants to activate DL duplication with dual connectivity (DC) and non-ideal backhaul, or with different queuing delays, there is no convenient way to indicate the UE to use a different reordering timer. This similarly results in degraded latency in case of PDCP COUNT gaps.

One way of addressing this would be for the NW to configure a larger reordering timer, either in advance (in which case one drawback is that in case duplication is not used, the latency is unnecessarily degraded due to the PDCP COUNT gap) or at the time duplication is activated (in which case one drawback is that RRC signalling must then be added, which is not adapted to easily trigger the DL duplication when this is required, especially in cell edge scenarios) . For example, when a PDCP entity is configured, the UE could be configured to have a larger reordering timer.

Some embodiments of the disclosed technology instead preconfigure the additional/alternative reordering timer and use a mechanism to select which reordering timer to use (for example, they may use a MAC CE (as for UL) and/or use another a mechanism to choose which reordering timer to use so as to avoid the two drawbacks mentioned above.

Some examples of embodiments which provide enhanced BSR operation for duplication in Carrier Aggregation “CA” (MAC layer) will now be described, however, it is helpful if first some context is given for carrier aggregation duplication and regular Buffer Status Reports.

Background on CA duplication

When CA duplication is configured and activated for a radio bearer, a PDCP entity performs PDCP PDU duplication and submits the original and duplicate PDCP PDU towards two different radio link control (RLC) entities. These two RLC entities submit corresponding RLC PDUs towards the same MAC entity through two logical channels. In order to ensure that those RLC PDUs are sent on different carriers, these logical channels are restricted to use different component carriers (or equivalently Serving Cells) . This is illustrated in Figure 1 of the accompanying drawings in which a logical channel LCH1 is restricted to use transport carrier channel CC1 and transport carrier channel CC2, and another logical channel LCH2 is restricted to use another transport carrier channel CC3. The mapping can be configured by radio resource control (RRC) , for instance by setting the parameter lcp-allowedServingCells.

Background on regular BSR

The legacy principle for regular BSR (triggered upon new data arrival) , which is reused in NR, is that a regular BSR should be triggered when there is new UL data available for a higher priority LCH, compared to the priority of LCH already containing available UL data.

This includes 2 cases:

i) new UL data is available for a LCH, and there was no data available for transmission in any other LCH;

ii) new UL data is available for a LCH, and the priority of the LCH is higher than the priority of all other LCHs already containing available UL data.

Logical channels (LCHs) must be assigned to a Logical Channel Group (LCG) which defines the granularity with which the buffer size is reported to the NW (all data from LCHs belonging to the same LCG are aggregated for the purpose of reporting the UL data available for transmission to the NW in BSR) . It is noted (for reference) that any data for LCHs which is not mapped to a LCG is not reported and will not trigger BSR. “UL data available for transmission for a LCH” , “UL data available for a LCH” or “LCH containing available UL data” refers to UL data which will end up being submitted to the corresponding LCH, and which is buffered in RLC or PDCP, as specified in the MAC specification 38.321v200. 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 and 38.323 [3] [4] and the full MAC specification 38.321v200 text is as follows: a BSR shall be triggered if any of the following events occur: the MAC entity has new UL data available for a logical channel which belongs to an LCG; and either the new 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 to as ′Regular BSR′ .

CA duplication and regular BSR trigger

Some embodiments of the disclosed technology address an ultra-reliable low latency communications (URLLC) use case in which UE has one dedicated radio bearer (DRB) configured to serve URLLC traffic. Typically, the corresponding URLLC LCH will be configured with a higher priority than other LCHs, e.g. the enhanced Mobile Broadband (eMBB LCH (s) ) . This ensures that a regular BSR is triggered upon new URLLC UL data arrival, even if there is already available UL data for eMBB. The traffic pattern for URLLC is expected to be sporadic short UL data bursts.

When CA duplication is configured, it is expected that the duplicated URLLC LCH will be configured with similar high priority than original URLLC LCH. In one scenario, the same priority for both LCHs is used. In order for a base station (which in NR is referred to as the gNodeB (gNB) ) scheduler to discriminate for which LCH (hence carrier) UL data resources are needed, both LCHs can be mapped to different logical channel groups (LCGs) .

When a first burst of data arrives for URLLC, new UL data is simultaneously available for both LCHs. If the MAC entity considers both arrival simultaneously, two regular BSRs will be triggered, one for each LCH. The gNB will have timely knowledge of buffer status (BS) for both LCHs, as expected. When a second burst of data arrives for URLLC, if the first burst was successfully transmitted on both links, same behaviour is expected, and no problem is seen. However, it is possible that one of the link encounter issues, e.g. due do temporary blockage related to high-frequency used in NR.

In some situations the first burst transmission is not complete on the duplicated link (meaning, there is still available UL data for the duplicated LCH) at the time of the arrival of the second burst of data. In this scenario, the new UL data arrival will not trigger a BSR because there is already available UL data for a LCH of the same priority.

The gNB does not have timely knowledge of the BS of the original LCH. The gNB scheduler can only get knowledge of this data arrival thanks to periodic BSR, which can occur several ms later depending on the configuration. This can be contrasted with a situation where the duplicated link was not established in the first place which case a BSR would have been triggered upon data arrival for the second burst of data. To avoid this issue, it could be possible to configure the duplicated LCH with a lower priority than the initial LCH. However, the opposite issue may happen, whereby some data is stuck in the original LCH and would prevent the new UL data arrival in the duplicated LCH to trigger a BSR.

Accordingly, when CA duplication is activated for a RB, with existing BSR procedure, a regular BSR might not be triggered upon new UL data arrival for that RB whenever data for this RB is stuck in one leg, even if data is not stuck on the other leg. Due to this problem, activation of CA duplication might even degrade the latency of the RB, contrary to one of the intended goal of duplication. This problem does not occur with dual connectivity (DC) duplication since in DC there are 2 MAC entities, for Master Cell Group (MCG) and Secondary Cell Group (SCG) , with independent BSR procedures towards Master Node (MN) and Secondary Node (SN) schedulers.

Some embodiments address the above by modifying the regular BSR triggering mechanism as follows for an example of a network configuration which has 3 dedicated radio bearers (DRBs) pre-configured for duplication. The three DRBs are configured as set out in table 1 in which numbered Logical Channels are referred to as LC1 .... LC6 and in which: LC1/LC2 are both legs of duplicated DRB A; LC3/LC4 are both legs of duplicated DRB B; and LC5/LC6 are both legs of duplicated DRB C. In this example, five serving cells (SCs) /component carriers (CCs) are provided and the logical channel (LCH) mapping restrictions for serving cells (SCs) /component carriers (CCs) to this set of logical channels is as set out in the table below (this indicates the allowed serving cells/component carriers for each of these logical channels) .

	CC1	CC2	CC3	CC4	CC5
LC1	X	X
LC2			X	X	X
LC3	X
LC4			X
LC5	X		X
LC6		X		X

Table 1: Example Logical Channel (LCh) (referred to as LC1 ... LC5 in Table 1) Mappings to Component Carriers (CC1... CC5)

In this example of an embodiment of the disclosed technology the DRBs have similar priority and so the priority of the logical channels (LCHs) is the same across the DRBs. We assume also that priority of initial and duplicated LCHs are set equal. Hence in this example configuration, all LCHs (LC1 .... LC6 in Table 1) are configured with the same priority.

Consider now when, upon arrival of new data for a logical channel within a MAC entity, if the MAC entity checks already available data on a subset of LCHs, a regular BSR is only triggered if there is no already available data for LCHs of this subset of LCHs. In the baseline, this subset is all LCHs with higher or equal priority than the LCH for which new UL data arrives, across all LCGs. This subset is denoted as baseline subset. The presence of available data for any LCH in this subset prevents regular BSR triggering upon new UL data arrival for the considered LCH. The resulting regular BSR triggering procedure is equivalent to saying that a regular BSR is triggered if the already available data (if any) only pertains to LCHs with lower priority than the priority of the LCH with new UL data. With the example configuration described above, in which all LCHs have same priority, the baseline LCHs subsets would be as detailed below in Table 2, depending if new data (ND) arrives for LC1 up to LC6.

ND LC1

ND LC2

ND LC3

ND

				LC4	LC5	LC6
LC1	X	X	X	X	X	X
LC2	X	X	X	X	X	X
LC3	X	X	X	X	X	X
LC4	X	X	X	X	X	X
LC5	X	X	X	X	X	X
LC6	X	X	X	X	X	X

Table 2.

In this situation, when new data arrives on one LC, data already available on the corresponding LCH subset would prevent BSR triggering. All LCHs are considered in the LCH subset, hence any data stuck on any one of the LCHs (LC1 . . . LC6) will prevent BSR triggering. This causes two issues. One issue is that if data is stuck on either initial or duplicated leg of a DRB, the BSR would not be triggered (as discussed hereinabove) . This is because data on LC2 is checked in case of ND LC1 (New Data on LC1) , and vice-versa, and similarly for LC3/4 and LC5/6. The other issue is that considering several DRBs, data stuck corresponding to one DRB can prevent BSR triggering of another DRB, even if the another DRBs was configured to use more component carriers (CCs) . If CC1 is blocked, LC3 data might be stuck (as LC3 is configured to use only CC1 in this example) . This would prevent BSR triggering for all the other LCHs, even though they are allowed to use other CCs.

In some embodiment, one or more “restricted LCHs” are used. The term “restricted LCH” unless stated otherwise denotes a LCH which is restricted to use specific component carriers (CCs) or equivalently serving cells (SCs) for transmission. This can be configured by RRC for instance with the parameter lcp-allowedServingCells.

In some examples of embodiments of the disclosed technology, a MAC entity has new UL data available for a restricted LCH which belongs to a logical channel group (LCG) . In these examples of embodiments, for example, when checking for a LCH containing available UL data for the purpose of triggering a regular BSR, a further subset of the LCHs is used in addition to the baseline subset described herein above. For instance, when checking for a LCH containing available UL data for the purpose of triggering a regular BSR, the MAC entity will consider LCHs pertaining both to the baseline subset and to the further subset.

In an embodiment, the further LCHs subset is the set of LCHs which are allowed to use at least one same component carrier/serving cell as the restricted LCH for which the MAC entity has new UL data available. (Equivalently, the further LCHs subset is the set of all LCHs excluding those LCHs which are not allowed to use any of the carrier/serving cell allowed for the restricted LCH for which MAC entity has new UL data available. )

With the example configuration described above, the resulting LCHs subsets are detailed below in Table 3, depending if new data (ND) arrives for LC1 up to LC6.

Table 3

The above set of LCHs which comprises all LCHs which are allowed to use at least one component carrier/serving cell which is the same as the restricted LCH for which the MAC entity has new UL data available resolves the first issue mentioned above in the event that data is stuck on either initial or duplicated leg of a DRB, the BSR would not be triggered, as for one DRB, data available on one leg is not checked upon arrival of data on the other leg (indicated by “- “in Table 3 above) .

However, the second issue, in which considering several DRBs, data stuck corresponding to one DRB can prevent BSR triggering of another DRB, even if the another DRBs was configured to use more CCs and prevent BSR triggering of all other LCHs, even though they are allowed to use other CCs, remains. If CC1 is blocked, LC3 may have data stuck, and will prevent BSR triggering from new data on LC1, even though LC1 can also use CC2.

The would result in a modification to known BSR techniques, such as that proposed in MAC specification 38.321v200 for example, and according to an embodiment of the disclosed technology a BSR is triggered if any of the following event occur:

- the MAC entity has new UL data available for a logical channel which belongs to an LCG; and either

- the new 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, and which is allowed to use at least one of the serving cell (s) allowed for the logical channel with new UL data ; or

- none of the logical channels which belong to an LCG and which are allowed to use at least one of the serving cell (s) allowed for the logical channel with new UL data contains any available UL data;

in which case the BSR is referred below to as ′Regular BSR′ ;

Accordingly, one embodiment of the invention comprises a method of triggering a BSR a method of triggering a BSR comprising:

determining if a MAC entity has new uplink (UL) data available for a logical channel which belongs to a logical channel group (LCG) ; and

triggering a BSR responsive to determining either:

the new uplink (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, and which is allowed to use one or more or all of the serving cells allowed to be used by the logical channel with new UL data ; or

that none of the logical channels which belong to any LCG and which are allowed to use any of the serving cell (s) allowed for the logical channel with new UL data contain any available UL data.

The BSR so triggered is referred below to as ′Regular BSR′ ;

In a another embodiment, the further LCHs subset is the LCHs which are allowed to use at least the same component carriers/serving cells (i.e., all) as the restricted LCH for which MAC entity has new UL data available. Equivalently, the further LCHs subset is all LCHs excluding those LCHs which are not allowed to use at least one of the carrier (s) /serving cell (s) allowed for the restricted LCH for which MAC entity has new UL data available.

With the example configuration described above, the resulting LCHs subsets are detailed below, depending if new data (ND) arrives for LC1 up to LC6.

Table 4:

This embodiment solves the issue with the problem of data being stuck on either initial or duplicated leg of a DRB when the BSR would not be triggered as for one DRB, data available on one leg is not checked upon arrival of data on the other leg (indicated by “- “in the table) .

The above embodiment also solves the problem arising when several DRBs are used and data stuck corresponding to one DRB prevents BSR triggering of another DRB, even if the another DRBs is configured to use more CCs Even if CC1 is blocked, and LC3 has data stuck, it does not prevent BSR triggering from new data on LC1, since LC1 can also use CC2. LC3 available data is only checked (i.e. can only prevent BSR) upon arrival of new data for LC3. In case of arrival of new data from a different LCH, LC3 available data is not considered since all others LCH can use a different CC than CC1. LC2 available data can prevent BSR triggering on new data arrival from LC4, because LC4 can only use CC3 which can already be used by LC2.

- the new 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, and which is allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data ; or

- none of the logical channels which belong to an LCG and which are allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data contains any available UL data;

in which case the BSR is referred to as ′Regular BSR′ ;

Accordingly, another example of a method of triggering a BSR according to an embodiment of the invention comprises:

triggering a BSR responsive to either:

- determining the new 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, and which is allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data ; or

- determining none of the logical channels which belong to an LCG and which are allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data contains any available UL data;

In another embodiment of the disclosed technology a serving cell mapping restriction is configured for a different purpose than duplication and the proposed regular BSR trigger update is configurable. The previous embodiments are extended to apply the new behaviour only when configured by radio resource control (RRC) , either explicitly (e.g. along with LCH or DRB/PDCP configuration) , or implicitly (for LCHs corresponding to duplicated DRBs) . This new behaviour can also be configured to apply only for a specific LCGs.

In another embodiment of the disclosed technology, “restricted LCH” refers to a LCH which is configured with one or more mapping restrictions, for example, such as those as specified in MAC specification 38.321v200., where RRC additionally controls the LCP procedure by configuring mapping restrictions for each logical channel:

- lcp-allowedSCS which sets the allowed Subcarrier Spacing (s) for transmission;

- lcp-maxPUSCH-Duration which sets the maximum PUSCH duration allowed for transmission;

- lcp-configuredGrantType1Allowed which sets whether a Configured Grant Type 1 can be used for transmission;

- lcp-allowedServingCells which sets the allowed cell (s) for transmission.

The other embodiments described herein may be similarly extendible/extended to consider not only any serving cells mapping restriction (s) , but also any other mapping restriction (s) .

Another example of an embodiment of the disclosed technology provides “fast BSR triggering” . In this example of an embodiment, a new trigger is defined. The new trigger is denoted as “fast BSR triggering” and can be configured by RRC on a LCH or DRB basis (in which case it applies to LCHs used by the DRB) .

In case of MAC entity has new UL data available for a LCH configured for “fast BSR triggering” which belongs to an LCG, when checking LCH containing available UL data for the purpose of triggering regular BSR, only that LCH shall be considered.

With the example configuration described above, the resulting LCHs subsets are detailed below as shown in Table 5, depending if new data (ND) arrives for LC1 up to LC6.

Table 5

The above embodiment also solves the problem arising when several DRBs are used and data stuck corresponding to one DRB prevents BSR triggering of another DRB, even if the another DRBs is configured to use more CCs. Whilst the above embodiment solve both of these issues, it nonetheless has some drawbacks, for example, a new BSR trigger is to be specified, rather than modifying an existing trigger, and the trigger is on a LCH basis. This can leads to overhead if we consider the case of several LCHs, as in prior art a LCH does not trigger BSR even there is already higher or equal priority LCH data available. Also, the fast BSR trigger needs to be configured, either explicitly (by RRC, for instance as part of LCH configuration) or implicitly (for instance for LCHs corresponding to duplicated DRBs) .

Accordingly, one example of an embodiment of the disclosed technology provides a method for triggering a buffer status report (BSR) modifies known techniques (for example, the technique known from MAC specification 38.321v200) . According to this example embodiment a BSR shall be triggered if any of the following events occur:

- the new 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; or

- the new UL data belongs to a logical channel configured for fast BSR triggering, and the logical channel does not contain already available data

in which case the BSR is referred below to as ′Regular BSR′ .

triggering a BSR responsive to either:

determining the new 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

determining none of the logical channels which belong to an LCG contains any available UL data; or

determining the new UL data belongs to a logical channel configured for fast BSR triggering, and

the logical channel does not contain already available data

Another example of embodiment also provides a method of very fast BSR triggering. In this example of an embodiment, a new trigger is defined. The new trigger is denoted as “very fast BSR triggering” and can be configured by RRC on a LCH or DRB basis (in which case it applies to LCHs used by the DRB) . In case of MAC entity has new UL data available for a LCH configured for “very fast BSR triggering” which belongs to an LCG, a regular BSR is triggered, independently of any available UL data.

The embodiment triggers regular BSR even more quickly but may have some drawbacks as it requires a large additional BSR overhead and will trigger more BSR then known techniques (in known techniques new data for a LCH does not trigger BSR if there is already pending data for that LCH as padding or periodic BSR can handle this) .

the new UL data belongs to a logical channel configured for fast BSR triggering

in which case the BSR is referred below to as ′Regular BSR′ ;

In some embodiments relating to enhanced DL PDCP duplication operation (PDCP layer) , the UE is configured by RRC with two RLC entities /logical channels for one radio bearer. The NW might use these LCHs for packet duplication in DL. Figure 2A of the accompanying drawings shows as examples how a radio bearer not configured for duplication differs from a radio bearer which is configured for duplication (see Figure 2B of the accompanying drawings) . Once the NW has configured by RRC a radio bearer to use DL PDCP duplication (configuring two RLC entities /logical channels for one radio bearer ) , the NW is able to activate/deactivate a downlink (DL) packet duplication operation whenever needed without the need to inform the UE. The duplication operation has no direct impact on UE packet data control protocol (PDCP) receive operation as reordering and duplicate removal operation are already needed and supported in the baseline NR PDCP operation.

Figure 3 shows schematically an example of a PDCP receive operation which uses a PUSH based reordering window. The reordering window lower edge “RX_DELIV” is pushed by arrival of PDCP PDU with COUNT = RX_DELIV, or by expiry of the reordering timer. The reordering timer is started whenever it was not already running and a gap is created in the received COUNT sequence. The DL PDCP reordering operation is used whether in-order or out-of-order delivery to application layer is configured.

In New Radio (NR or 5G) , radio link control (RLC) delivers complete RLC service data units (SDUs) to the PDCP as soon as they are received, i.e. contrary to LTE (or 4G) there is no in- order-delivery from RLC to PDCP. Hence, even when a single LCH is used, PDCP reordering needs to be configured:

for the unacknowledged mode (UM) , the reordering timer shall be higher than the maximum HARQ re-transmission delay;

for the acknowledged mode (AM) , the reordering timer shall be higher than the maximum automatic repeat request (ARQ) re-transmission delay

However, the reordering timer introduces delay in delivering PDCP SDUs to upper layers whenever in-order-delivery is configured and there is a gap in the PDCP sequence. Hence, the smallest possible value should be configured.

It is known that when 2 LCHs are used for duplication, then in case of DC with non-ideal backhaul or in case of DC/CA with different queuing delays, an additional delay between both LCHs is expected. Currently, a UE is not aware if/when DL duplication is used or not. So if the NW wants to activate DL duplication with DC and non-ideal backhaul, or with different queuing delays, the NW will have to configure a larger reordering timer. Using known procedures, the NW configures a larger reordering timer with RRC signalling. This is be done either

- at the time DL duplication is configured or more generally before activation of DL duplication. However, such known procedures may cause a problem if duplication is not activated, as while duplication is not activated the latency is degraded in case of PDCP COUNT gap. The PDCP COUNT gap can occur due to packet loss on the air interface (in UM) , or PDCP PDU discard from the NW side (in AM or UM) . In case such PDCP COUNT gap occurs, the PDCP entity at the UE will wait the missing PDCP PDU (s) during a longer time than needed, as it would actually wait for potential arrival of the PDCP PDU from the alternative leg.

- at the time duplication is activated: the problem is added RRC signalling, which is not adapted to easily trigger the DL duplication when required, especially in cell edge scenarios. That’s the reason why a MAC CE was introduced to activate/deactivate duplication in UL, while a RRC signalling would have been also possible.

One example of an embodiment of the disclosed technology pre-configures a reordering timer to be used when DL duplication is activated. This can be part of PDCP entity configuration.

In addition to baseline reordering timer to be used when DL duplication is not activated, an alternative reordering timer can be configured to be used when DL duplication is activated.

The activation/deactivation of DL duplication can be detected:

explicitly, by using a MAC CE sent by the NW in DL to indicate activation/deactivation of DL duplication, similarly as for activation/deactivation of UL duplication;

implicitly, by considering DL duplication is activated whenever UL duplication is activated (such behaviour can be configured by RRC on a RB basis) ;

implicitly, by considering DL duplication is activated whenever data for a RB is received on a second link after being received on a first link, an deactivated whenever data for a RB is only received on one link during a configured time

One example of an embodiment of the disclosed technology pre-configures a reordering timer for downlink (DL) dual link operation, for example, such as may be used whenever the PDCP DL entity is associated with two radio link control (RLC) entities. This may be suitable for covering both duplication and split operations, both being dual link operations.

One example of an embodiment of the disclosed technology pre-configures a reordering timer for uplink (UL) PDCP duplication (and/or (instead of) down link (DL) PCDP) . This may also be suitable for when DC (dual connectivity) is used.

In one example of an embodiment of the disclosed technology, packet duplication is activated by a MAC CE from either a master node (MN) or secondary node (SN) . The (receiving) Packet Data Convergence Protocol (PDCP) entity is located at MN or SN. The PDCP entity needs to know that UL duplication was activated/deactivated to adapt the reordering timer, however this decision might be taken by the node which does not host the PDCP entity. In this example of an embodiment, the node activating/deactivating the UL duplication indicates such decision to the node hosting the PDCP entity (if different) through Xn/X2 signalling. This enables the node hosting the PDCP entity to adapt the reordering timer.

Although not shown in detail any of the devices or apparatus that form part of the network may include at least a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method of any aspect of the present invention. Further options and choices are described below.

The signal processing functionality of the embodiments of the invention especially the gNB and the UE may be achieved using computing systems or architectures known to those who are skilled in the relevant art. Computing systems such as, a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc. ) , mainframe, server, client, or any other type of special or general purpose computing device as may be desirable or appropriate for a given application or environment can be used. The computing system can include one or more processors which can be implemented using a general or special-purpose processing engine such as, for example, a microprocessor, microcontroller or other control module.

The computing system can also include a main memory, such as random access memory (RAM) or other dynamic memory, for storing information and instructions to be executed by a processor. Such a main memory also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor. The computing system may likewise include a read only memory (ROM) or other static storage device for storing static information and instructions for a processor.

The computing system may also include an information storage system which may include, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disc (CD) or digital video drive (DVD) read or write drive (R or RW) , or other removable or fixed media drive. Storage media may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drive. The storage media may include a computer-readable storage medium having particular computer software or data stored therein.

In alternative embodiments, an information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components may include, for example, a removable storage unit and an interface , such as a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to computing system.

The computing system can also include a communications interface. Such a communications interface can be used to allow software and data to be transferred between a computing system and external devices. Examples of communications interfaces can include a modem, a network interface (such as an Ethernet or other NIC card) , a communications port (such as for example, a universal serial bus (USB) port) , a PCMCIA slot and card, etc. Software and data transferred via a communications interface are in the form of signals which can be electronic, electromagnetic, and optical or other signals capable of being received by a communications interface medium.

In this document, the terms ‘computer program product’ , ‘computer-readable medium’ and the like may be used generally to refer to tangible media such as, for example, a memory, storage device, or storage unit. These and other forms of computer-readable media may store one or more instructions for use by the processor comprising the computer system to cause the processor to perform specified operations. Such instructions, generally referred to as ‘computer program code’ (which may be grouped in the form of computer programs or other groupings) , when executed, enable the computing system to perform functions of embodiments of the present invention. Note that the code may directly cause a processor to perform specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory

In an embodiment where the elements are implemented using software, the software may be stored in a computer-readable medium and loaded into computing system using, for example, removable storage drive. A control module (in this example, software instructions or executable computer program code) , when executed by the processor in the computer system, causes a processor to perform the functions of the invention as described herein.

Furthermore, the inventive concept can be applied to any circuit for performing signal processing functionality within a network element. It is further envisaged that, for example, a semiconductor manufacturer may employ the inventive concept in a design of a stand-alone device, such as a microcontroller of a digital signal processor (DSP) , or application-specific integrated circuit (ASIC) and/or any other sub-system element.

It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to a single processing logic. However, the inventive concept may equally be implemented by way of a plurality of different functional units and processors to provide the signal processing functionality. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organisation.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may optionally be implemented, at least partly, as computer software running on one or more data processors and/or digital signal processors or configurable module components such as FPGA devices. Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognize that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Also, the inclusion of a feature in one category of claims does not imply a limitation to this category, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. In addition, singular references do not exclude a plurality. Thus, references to ‘a’ , ‘an’ , ‘first’ , ‘second’ , etc. do not preclude a plurality.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ or “including” does not exclude the presence of other elements.

Claims

A method of triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the method comprising:

determining if a medium access control (MAC) entity has new uplink data available for a first logical channel belonging to a logical channel group;

and if so, if it is determined either that:

the first logical channel with new uplink data has a higher priority than the priority of any other logical channels belonging to any logical channel group with available uplink data, and where the other logical channels are allowed to use at least one of the serving cells allowed for the first logical channel with the new uplink data; or

that none of the other logical channels which belong to any logical channel group and which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data,

triggering a buffer status report.
A method as claimed in claim 1, wherein, the buffer status report is triggered if it is determined that:

the new 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, and which is allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data ; or

none of the logical channels which belong to an LCG and which are allowed to use at least all of the serving cell (s) allowed for the logical channel with new UL data contains any available UL data.
A method as claimed in any one of claims 1 or 2, wherein the method of triggering of the buffer status report is configurable in the wireless communications network by radio resource control.
A method as claimed in claim 3, wherein the radio resource control configures the wireless network to implement the method of triggering the buffer status report according to claim 1 or 2, either explicitly when logical channels or dedicated radio bearer/packet data convergence protocol is being configured in the network or implicitly when logical channels are configured which correspond to duplicated dedicated radio bearers.
A method as claimed in any previous claim, in which the method is implemented only for one or more specific logical channel groups in the wireless communications network.
A method of triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the method comprising:

determining if a medium access control entity has new uplink data available for a logical channel belonging to a logical channel group;

and if so, if it is determined either that:

the new uplink data belongs to a logical channel with a higher priority than the priority of any logical channel containing available uplink data which belong to any logical channel group; or

no other logical channels which belong to any logical channel group contain any available up link data; or

the new uplink data belongs to a logical channel configured for fast buffer status report triggering,

triggering a buffer status report.
A method as claimed in claim 6, wherein the buffer status report triggering is configured by radio resource control on a logical channel basis or on a logical channel used by a dedicated radio bearer basis.
A method as claimed in claim 6, wherein the step of triggering the buffer status report further requires the new uplink data to belong to a logical channel which does not contain already available data.
A method as claimed in any one of the preceding claims, wherein the method is performed in a radio access network for a New Radio/5G communications network.
Apparatus for triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the apparatus comprising:

means configured to provide a first positive determination if a medium access control entity has new uplink data available for a first logical channel belonging to a logical channel group;

means configured to provide a second positive determination if the new uplink data belonging to the first logical channel has a higher priority than a priority of available uplink data on any other logical channels belonging to the logical channel group when the available uplink data contained in the other logical channels is allowed to use at least one of the serving cells allowed for the first logical channel with the new up link data; and

means configured to provide a third positive determination if none of the other logical channels which belong to the logical channel group to which the first logical channel belongs which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data, and

means configured to, responsive to a positive first determination and either a positive second determination or a positive third determination, cause the triggering of a buffer status report.
A wireless network comprising means to implement any of the methods as claimed in any one of claims 1 to 5 and/or claims 6 to 9.
A wireless network configured operate using a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication and the wireless network is capable of activating down link packet duplication, the network further comprising means to pre-configuring a reordering timer for use when a down link duplication is activated as part of the packet data convergence protocol configuration of the wireless network.
A wireless network as claimed in claim 12, wherein the network is configured to pre-configure a re-ordering timer if activation and/or deactivation of at least down link packet duplication is detected by using a MAC CE.
A wireless network as claimed in claim 12 or 13, wherein the network is configured to pre-configure a re-ordering timer if activation and/or deactivation of uplink packet duplication is detected by using a MAC CE.
A wireless network as claimed in any one of claims 12 to 13, wherein the network is configured to consider whenever uplink activation is detected that down link packet duplication is activated.
A wireless network as claimed in any one of claims 12 to 13, wherein the network is configured by radio resource control on a radio bearer basis to consider whenever uplink activation is detected that down link packet duplication is activated.
A wireless network as claimed in any one of claims 12 to 13, wherein the network is configured to consider down link duplication is activated if it is determined that data for a radio bearer is received on a second link after being received on a first link.
A wireless network as claimed in claim 17, wherein the network is configured to consider down link duplication is deactivated whenever data for a radio bearer is received on only one link during a predetermined interval of time.
A wireless network as claimed in any one of claims 12 to 18, wherein the wireless network includes at least one node at which a PDCP entity is located which is configured to adapt the reordering timer.
A wireless network as claimed in claim 19, wherein:

packet duplication is activated by a MAC CE from either a master node (MN) or a secondary node (SN) of the wireless network and the receiving PDCP entity is located either at the master node or the secondary node, and

wherein, whenever a master or secondary node determines to activate and/or deactivate an uplink duplication, an indication of the decision is communicated to the other of the master or secondary node at which the PDCP entity is located.
A wireless network as claimed in claim 21, wherein an indication of the decision is communicated using Xn/X2 signalling to the other of the master or secondary node at which the PDCP entity is located to enable the node holding the PCDP entity to adapt the reordering timer.
A wireless communications networks as claimed in any of claims 12 to 21 which is further configured with means to implement a method according to any one of claims 1 to 9.
A network apparatus comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method as claimed in any one of claims 1 to 9.
A non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method according to any of claims 1 to 9.
A method for triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the method comprising:

determining, by a network node, at least two conditions for triggering sending of a buffer status report, the first condition comprising:

if a medium access control entity has new uplink data available for a first logical channel belonging to a logical channel group; and

at the at least second condition comprising one or more of:

if the new uplink data belonging to the first logical channel has a higher priority than a priority of available uplink data on any other logical channels belonging to the logical channel group when the available uplink data contained in the other logical channels is allowed to use at least one of the serving cells allowed for the first logical channel with the new up link data;

if none of the other logical channels which belong to the logical channel group to which the first logical channel belongs which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data;

if the new uplink data belongs to a logical channel with a higher priority than the priority of any logical channel containing available uplink data which belong to any logical channel group;

if no other logical channels which belong to any logical channel group contain any available up link data; or

if the new uplink data belongs to a logical channel configured for fast buffer status report triggering

triggering transmission of the buffer status report when the at least two conditions are met.
A method of triggering a buffer status report in a wireless communication network operating a packet data convergence protocol in which a plurality of logical channels are used to provide packet duplication, the method comprising:

determining if a medium access control entity has new uplink data available for a first logical channel belonging to a logical channel group;

and if so, if it is determined either that:

the new uplink data belonging to the first logical channel has a higher priority than a priority of available uplink data on any other logical channels belonging to the logical channel group when the available uplink data contained in the other logical channels is allowed to use at least one of the serving cells allowed for the first logical channel with the new up link data; and/or

that none of the other logical channels which belong to the logical channel group to which the first logical channel belongs which are allowed to use at least one of the serving cell (s) allowed for the first logical channel with the new uplink data contain any available UL data,

triggering a buffer status report.