WO2021242159A1

WO2021242159A1 - Dual connectivity capability signaling

Info

Publication number: WO2021242159A1
Application number: PCT/SE2021/050372
Authority: WO
Inventors: Stefan Wager; Lian ARAUJO
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2020-05-28
Filing date: 2021-04-22
Publication date: 2021-12-02

Abstract

Methods, apparatuses and computer program products for handling information regarding user equipment, UE, capabilities for supporting band combinations in multi-connectivity. An examplemethod, performed by a UE, comprises indicating (1110), in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. The method further comprises including (1120), in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.(Figure 11 for publication)

Description

DUAL CONNECTIVITY CAPABILITY SIGNALING

TECHNICAL FIELD

The present disclosure generally relates to the field of wireless network communications, and more particularly to techniques for signaling user equipment (UE) capabilities with respect to dual connectivity.

BACKGROUND

Wireless systems developed by members of the 3 "'-Generation Partnership Project (3GPP) include the fourth-generation wireless network widely known as LTE, which refers to the fourth- generation radio access technology formally called Evolved Universal Terrestrial Radio Access (E-UTRA), and the fifth-generation wireless network technology often referred to as “NR,” or “New Radio.” Corresponding to these radio access technologies are standards for core networks: the Evolved Packet Core (EPC), for fourth-generation networks; and the 5G Core (5GC), for fifth-generation networks. Notably, however, as discussed in further detail below, a NR radio access network (RAN) may be connected to an EPC, rather than a 5GC, in some deployments. This provides for a range of options for interaction and cooperation between various combinations of LTE and NR base stations and core networks.

One area where these options must be considered is the area of dual connectivity (DC), which allows for a user equipment (UE) to be simultaneously connected to two serving cells or cell groups, where the different cells potentially operate using different radio access technologies and/or in different frequency bands. DC is generally used in NR (5G) and LTE systems to improve UE transmit and receive data rate. With DC, the UE typically operates initially a serving cell group called a master cell group (MCG). The UE is then configured by the network with an additional cell group called a secondary cell group (SCG). Each cell group (CG) can have one or more serving cells. The MCG and SCG can be operated from geographically non-collocated gNBs. The MCG and SCG can be operated with corresponding serving cells belonging to different frequency ranges and/or corresponding serving cells in same and different frequency ranges. In an example, an MCG can have serving cells in Frequency Range 1 (FR1 ), which refers to frequencies below 6 GHz, while the SCG can also have serving cells in FR1. There are several different ways to deploy a 5G network, with or without interworking with LTE (also referred to as E-UTRA) and evolved packet core (EPC). These options are depicted in Figure 1. In principle, NR and LTE can be deployed without any interworking, that is, a gNB (3GPP terminology for an NR base station) in NR can be connected to a 5G core network (5GC) and an eNB (3GPP terminology for an LTE base station) can be connected to an EPC, with no interconnection between the two. These are illustrated as Option 1 and Option 2 in Figure 1, with the latter often being referred to as NR stand-alone (SA) operation. However, to facilitate a rapid deployment of NR technology, the first supported version of NR is so-called EN-DC (E- UTRAN-NR Dual Connectivity), illustrated by Option 3. In such a deployment, dual connectivity between NR and LTE is applied with LTE as the master and NR as the secondary node. The RAN node (gNB) supporting NR may not have a control plane connection to core network (EPC); instead, it relies on the LTE as master node (MeNB). This is also called “Non- standalone NR” Notice that in this case, the functionality of an NR cell is limited and would be used for connected mode UEs as a booster and/or diversity leg, but an RRC EDLE UE cannot camp on these NR cells.

With the introduction and deployment of 5GC, other options may be also valid. As noted above, Option 2 supports stand-alone NR deployment where gNB is connected to 5GC. Similarly, LTE can also be connected to 5GC using option 5 (also known as eLTE, E-UTRA/5GC, or LTE/5GC); such a node can be referred to as an ng-eNB. In these cases, both NR and LTE are seen as part of the next-generation RAN (NG-RAN), and both the ng-eNB and the gNB can be referred to as NG-RAN nodes.

Option 4 and Option 7 as illustrated in Figure 1 are other variants of dual connectivity between LTE and NR which will be standardized as part of NG-RAN connected to 5GC, denoted by MR- DC (Multi-Radio Dual Connectivity). Under the MR-DC umbrella are:

• EN-DC (Option 3): LTE is the master node and NR is the secondary (EPC CN employed)

• NE-DC (Option 4): NR is the master node and LTE is the secondary (5GCN employed) . NGEN-DC (Option 7): LTE is the master node and NR is the secondary (5GCN employed) • NR-DC (variant of Option 2): Dual connectivity where both the master and secondary are NR (5GCN employed). Even though NR-DC nomenclature is used, there are specific NR-DC cases that may be deployed, e g.: o Rel-15 NR-DC, where the UE supports only FR1 -FR2 NR-DC, meaning that MCG contains only bands in FR1 , and the SCG only bands in Frequency Range 2 (FR2), i.e., bands between 24.25 GHz and 52.6 GHz. o intra-FR NR-DC, where the UE supports only NR-DC within FR1 -only or FR2- only, meaning that either both MCG and SCG contain only bands in FR1 , or both MCG and SCG contain only bands in FR2. Because different operators will take different migration paths for updating their wireless networks, it is possible to have deployments with multiple options in parallel in the same network. For example, there could be eNB base stations supporting Options 3, 5 and 7 in the same network as NR base stations supporting Options 2 and 4. In combination with dual connectivity solutions between LTE and NR, it is also possible to support CA (Carrier Aggregation) in each cell group (i.e., MCG and SCG) and dual connectivity between nodes on the same RAT (e g., NR-NR DC). For the LTE cells, a consequence of these different deployments is the co-existence of LTE cells associated to eNBs connected to EPC, 5GC, or to both EPC/5GC.

While DC is standardized for both LTE and E-UTRA -NR DC (EN-DC), LTE DC and EN-DC are designed differently when it comes to which nodes control what Basically, there are two options:

• a centralized solution (like LTE-DC), or

• a decentralized solution (like EN-DC).

Figure 2 illustrates a schematic of the control plane architecture for LTE DC and EN-DC. The main difference here is that in EN-DC, the secondary node (SN) has a separate Radio Resource Control (RRC) entity, illustrated as NR RRC. This means that the SN can control the UE also. Sometimes this can be done without the knowledge of the master node (MN), but often the SN needs to coordinate with the MN. In LTE-DC, the RRC decisions are always coming from the MN (MN to UE). Note however, the SN still decides the configuration of the SN, since it is only the SN itself that has knowledge of what kind of resources, capabilities, etc., it has.

For EN-DC, the major changes compared to LTE DC are:

• The introduction of split bearer from the SN (known as SCG split bearer)

• The introduction of split bearer for RRC

. The introduction of a direct RRC from the SN (also referred to as SCG SRB).

Figures 3 and 4 show the User Plane (UP) and Control Plane (CP) architectures, respectively, for EN-DC. More particularly, Figure 3 illustrates network-side protocol termination options for MCG, SCG, and split bearers in MR-DC with EPC, i.e., EN-DC. Figure 4 shows the network architecture for the control plane in EN-DC.

The secondary node (SN) is sometimes referred to as SgNB (where gNB is an NR base station), and the MN as MeNB, in the case where the LTE is the master node and NR is the secondary node. In the other case, where NR is the master and LTE is the secondary node, the corresponding terms are SeNB and MgNB. Split RRC messages are mainly used for creating diversity, and the sender can decide to either choose one of the links for scheduling the RRC messages or duplicate the message over both links. In the downlink, path switching between the MCG or SCG legs or duplication on both is left to network implementation. On the other hand, for the uplink, the network configures the UE to use the MCG, SCG or both legs. The terms “leg,” “path,” and “RLC bearer” are used interchangeably throughout this document.

To configure a UE for DC, the controlling node needs to know the capabilities of the UE, e g., with respect to which bands it supports, which combinations of bands the UE is capable of using for DC, etc. In LTE, the eNB obtains the UE capabilities for a connecting UE from the MME. If the MME has not stored the capabilities for the UE (e g., upon ATTACH), the eNB fetches them from the UE.

Upon initial attach the MME does not yet know the UE capabilities and hence will not provide them in the "Initial Context Setup" message. In this case, the eNB has to acquire the required UE capabilities from the UE in this case, and should forward the received UE capabilities to the MME. This is depicted in Figure 5.

Upon handover, a source eNB transmits UE capabilities previously acquired to the target eNB, which may avoid the need for the target node to request UE capabilities again. However, the target eNB can also decide to request again UE capabilities, e.g., in case the support of a specific feature of interest to the eNB was not reported in the UE capabilities received from the source eNB. This is depicted in Figure 6.

A capability request may adopt different filters. In LTE the following filters can be included in the UECapabilityEnquiry message: begin specification excerpt

— ASNlSTART

UECapabilityEnquiry ::= SEQUENCE { rrc-Transactionldentifier RRC-TransactionIdentifier, criticalExtensions CHOICE { cl CHOICE { ueCapabilityEnquiry-r8 UECapabilityEnquiry-r8-IEs, spare3 NULL, spare2 NULL,sparelNULL criticalExtensionsFuture SEQUENCE {}

UECapabilityEnquiry-r8-IEs :: SEQUENCE { ue-CapabilityRequest UE-CapabilityRequest, nonCriticalExtension UECapabilityEnquiry-v8aO-IEs OPTIONAL

UECapabilityEnquiry-v8aO-IEs ::= SEQUENCE { lateNonCriticalExtension OCTET STRING OPTIONAL, nonCriticalExtension UECapabilityEnquiry-vl180-IEs OPTIONAL

UECapabilityEnquiry-vl180-IEs ::= SEQUENCE { requestedFrequencyBands-rll SEQUENCE (SIZE (1..16))OF FreqBandlndicator-rl1

OPTIONAL, nonCriticalExtension UECapabilityEnquiry-vl310-IEs

OPTIONAL

UECapabilityEnquiry-vl310-IEs ::= SEQUENCE { requestReducedFormat-rl3 ENUMERATED {true} OPTIONAL Need ON requestSkipFallbackComb-r13 ENUMERATED {true} OPTIONAL, Need

ON requestedMaxCCsDL-r13 INTEGER (2..32) OPTIONAL, Need ON requestedMaxCCsUL-r13 INTEGER (2..32) OPTIONAL, Need ON requestReducedIntNonContComb-r13 ENUMERATED {true} OPTIONAL, Need ON nonCriticalExtension UECapabilityEnquiry-vl430-IEs OPTIONAL UECapabilityEnquiry-vl430-IEs ::= SEQUENCE { requestDiffFallbackcombList-rl4 BandCombinationList-rl4 OPTIONAL, — Need

ON nonCriticalExtension UECapabilityEnquiry-vl510-IEs OPTIONAL

UECapabilityEnquiry-vl510-IEs ::= SEQUENCE { requestedFreqBandsNR-MRDC-rl5 OCTET STRING OPTIONAL, nonCriticalExtension UECapabilityEnquiry-vl530-IEs OPTIONAL

UECapabilityEnquiry-vl530-IEs ::= SEQUENCE { requestSTTI-SPT-Capability-rl5 ENUMERATED {true} OPTIONAL, eutra-nr-only-rl5 ENUMERATED {true} OPTIONAL, nonCriticalExtension UECapabilityEnquiry-vl550-IEs OPTIONAL

UECapabilityEnquiry-vl550-IEs ::= SEQUENCE { requestedCapabilityNR-r15 OCTET STRING OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL

UE-CapabilityRequest :: SEQUENCE (SIZE (1..maxRAT-Capabilities))OF RAT-Type

— ASNlSTOP

end specification excerpt

The UE, in turn, has different ways to echo those filters in the reported UECapabilitylnformation message. Typically, if the filter concerns, e.g., E-UTRA capabilities, an indication that the filter was used is included in UE-EUTRA-Capability Information Element (IE), which contains E- UTRA capabilities. For instance, requestSkipFallbackComb filter can be included in the UECapabilitylnformation message and echoed in the UE-EUTRA-Capability IE as follows: begin specification excerpt

RF-Parameters-vl310 ::= SEQUENCE { eNB-RequestedParameters-rl3 SEQUENCE { reducedlntNonContCombRequested-rl3 ENUMERATED {true} OPTIONAL, requestedCCsDL-rl3 INTEGER (2. .32) OPTIONAL, requestedCCsUL-rl3 INTEGER (2. .32) OPTIONAL, skipFallbackCombRequested-r!3 ENUMERATED {true} OPTIONAL

OPTIONAL, maximumCCsRetrieval-rl3 ENUMERATED {supported} OPTIONAL, skipFallbackCombinations-rl3 ENUMERATED {supported} OPTIONAL, reducedIntNonContComb-rl3 ENUMERATED {supported} OPTIONAL, supportedBandListEUTRA-vl310 SupportedBandListEUTRA-vl310 OPTIONAL, supportedBandCombinationReduced-rl3 SupportedBandCombinationReduced-rl3 OPTIONAL

Omittedparts skipFallbackCombRequested

Indicates whether requestSkipFallbackComb is requested by E-UTRAN.

. end specification excerpt .

The advertising of band combinations in the UE capabilities IE accounts for most of the capability size reported in the UECapabilitylnformation message. Here, signaling of UE capabilities for band combinations is described, with a focus on the optimizations adopted to reduce the signaling size. These optimizations aim to reduce the redundancy among features reported in band combinations. This is achieved by referring to identifiers (IDs), which point to a group of features (feature sets) that may be reused among band combinations. Each band combination entry in a UECapabilitylnformation message refers to one FeatureSetCombinationld, which identifies a Feature Set Combination. This is motivated by the fact that multiple band combinations may have the same Feature Set Combination, and thus can use an ID to refer to a common Feature Set Combination. In turn, a Feature Set Combination refers to multiple pairs of IDs, each pair of IDs referring to a Feature Set Downlink and a Feature Set Uplink. Each Feature Set (Downlink/Uplink) in turn refers to multiple Feature Sets per CC (Downlink/Uplink) ID.

Therefore, three different levels of IDs are adopted in a band combination entry, with each level representing features that can be reused in other band combinations, by referring to the same ID. This three-level structure associated with a band combination entry is illustrated in Figure 7.

A Feature set combination ( FeatureSetCombination IE) can be seen as a matrix of Feature Sets Downlink/Uplink. As an example, for a band combination comprising bands A, B, and C, each element represents a pair of ( FeatureSetDcwnlinkld / FeatureSetUplinkld), eg., as shown in Figure 8. The UE supports Feature Sets Downlink/Uplink advertised in the same position across bands in the band combination (in the same row, in the example of Figure 8).

Each FeatureSetDcwnlinkld points to one FeatureSetDownlink, in turn a FeatureSetDownlink refers to a FeatureSetDowlinkperCC-Id. This is illustrated in Figure 9, where FSCC1, FSCC2, etc., each refer to a FeatureSetDow linkperC C-Id. The structure is similar for the uplink. The number of FSCC’s is equal to the number of carriers supported for that band. Unlike other feature sets, the order of FSCC does not matter. Thus, the network may configure any of the carriers in accordance with any of the given FSCCs.

When UE capabilities are reported for EN-DC, NE-DC, and NGEN-DC, the capabilities are included in a UE-MRDC-Capability container. This MR-DC capability container has no FeatureSetDownlink or FeatureSetUplink IEs, but refers in its Feature Set Combination to Feature Sets for Downlink/Uplink used in NR and E-UTRA capabilities. This is shown in Figure 10, and implies that consistency should be applied among NR, MR-DC, and E-UTRA capabilities concerning Feature Set IDs. For consistency, then, when the network requests NR, MR-DC or E-UTRA capabilities for a UE, it should apply the same filter for all the requests. As an example, a network may:

• Request capabilities for E-UTRA, with a filter for E-UTRA bands A, B, C and NR bands D, E;

• Then request capabilities for NR, with the same filter;

• Finally, request capabilities for EN-DC, with the same filter.

By using the same filter in all the requests, it is guaranteed that the reported Feature Set IDs referred to in MR-DC capability container properly refer to Feature Sets identified in the NR and E-UTRA capability sets.

In EN-DC, capability coordination between network nodes in terms of UE-supported Band Combinations (BCs) is performed using configuration restriction information in inter-node message signalling. Having selected the BC for the MCG, the MN signals the allowed BCs for the SCG to the SN in ConfigRestrictlnfoSCG of CG-Configlnfo. ConfigRestrictlnfoSCG contains a list of BCs and corresponding Feature Sets that the SN can choose from. This is shown in the ASN.1 snippet from CG-Configlnfo reproduced below. begin specification excerpt

ConfigRestrictlnfoSCG ::= SEQUENCE { allowedBC-ListMRDC BandCombinationlnfoList OPTIONAL powerCoordination-FRl SEQUENCE { p-maxNR-FRl P-Max OPTIONAL, p-maxEUTRA P-Max OPTIONAL, p-maxUE-FRl P-Max OPTIONAL

OPTIONAL, servCelllndexRangeSCG SEQUENCE { lowBound ServCellIndex, upBound ServCellIndex

OPTIONAL,

Cond SN-Addition maxMeasFreqsSCG-NR INTEGER(1..maxMeasFreqsMN) OPTIONAL, maxMeasIdentitiesSCG-NR INTEGER(1..maxMeas!dentitiesMN) OPTIONAL,

BandCombinationlnfoList ::= SEQUENCE (SIZE (1..maxBandComb))OF BandCombinationlnfo

BandCombinationlnfo ::= SEQUENCE { bandCombinationIndex BandCombinationlndex, allowedFeatureSetsList SEQUENCE (SIZE (1..maxFeatureSetsPerBand))OF

FeatureSetEntrylndex

FeatureSetEntrylndex ::= INTEGER (1..maxFeatureSetsPerBand) end specification excerpt

In return, once the SN has selected the NR bands for the SCG configuration, it can inform the MN of the selected SCG band combination using selectedBandCombinationNR of CG-Config. This is shown in the ASN.1 snippet below. begin specification excerpt

CG-Config-IEs ::= SEQUENCE scg-CellGroupConfig OCTET STRING (CONTAINING RRCReconfiguration) OPTIONAL, scg-RB-Config OCTET STRING (CONTAINING RadioBearerConfig) OPTIONAL, configRestrictModReq ConfigRestrictModReqSCG OPTIONAL, drx-InfoSCG DRX-Info OPTIONAL, candidateCelllnfoListSN OCTET STRING (CONTAININGMeasResultList2NR) OPTIONAL, measConfigSN MeasConfigSN OPTIONAL, selectedBandCombinationNR BandCombinationlnfoSN OPTIONAL, fr-InfoListSCG FR-InfoList OPTIONAL, candidateservingFreqListNR CandidateservingFreqListNR OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL end specification excerpt

SUMMARY

In EN-DC and NR-DC as specified by Release 15 of the 3 GPP specifications, there are restrictions on the operation of the dual connectivity modes, such that there is no need for explicit signaling of which bands in a particular band combination (BC) supported by the UE can be used in a MCG, and which bands can be used in an SCG. In NR-DC as specified by Release 16 of the Specifications, however, FR1-FR1 NR-DC is supported, which means that it is no longer implicitly clear, from the UE capability signaling, which band entries in a BC can be set up in an MCG and which in a SCG. Further, Release 16 introduces asynchronous DC, in which the synchronization between MCG and SCG is more relaxed compared to synchronous DC. For some BCs, a given UE may support arbitrary grouping of bands into MCG and SCG, but for others there may be restrictions, such that asynchronous DC may only be supported by the UE between some of the band entries in the BC.

The techniques and apparatuses described herein address these problems.

An example method performed by a UE described herein includes the step of indicating, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. The UE further includes, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

Another example method performed by a base station, complementing the one summarized above, comprises receiving, in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. The base station further receives, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

Apparatuses and systems corresponding to the above-summarized methods, and many variants thereof, are also described in detail below.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates 3GPP scenarios for LTE and NR operation. Figure 2 illustrates control plane architecture for LTE DC and EN-DC.

Figure 3 and Figure 4 show the User Plane and Control Plane architectures for EN-DC.

Figure 5 shows UE capability signaling.

Figure 6 shows UE capability signaling.

Figure 7 illustrates a structure for identifying feature sets. Figure 8 illustrates an example of identifying feature sets for a band combination.

Figure 9 illustrates a further example of identifying feature sets for a band combination.

Figure 10 illustrates dependencies for feature set identification between NR MR-DC and E- UTRA capability signaling.

Figure 11 is a process flow diagram illustrating an example method, according to some embodiments. Figure 12 is a process flow diagram illustrating another example method, according to some embodiments.

Figure 13 is a block diagram illustrating an example network node.

Figure 14 is a block diagram illustrating an example UE, according to some embodiments. Figure 15 illustrates an example telecommunication network connected to a host via an intermediate network, in accordance with some embodiments.

Figure 16 illustrates a host computer communicating over a partially wireless connection with, in accordance with some embodiments.

Figure 17 is a flowchart illustrating methods implemented in a communication system that includes a host computer, a base station, and a user equipment, in accordance with some embodiments.

Figure 18 is another flowchart illustrating methods implemented in a communication system that includes a host computer, a base station, and a user equipment, in accordance with some embodiments. Figure 19 shows another flowchart illustrating methods implemented in a communication system that includes a host computer, a base station, and a user equipment, in accordance with some embodiments.

Figure 20 shows still another flowchart illustrating methods implemented in a communication system that includes a host computer, a base station, and a user equipment, in accordance with some embodiments.

Figure 21 is a block diagram illustrating functional components of an example network node, according to some embodiments.

Figure 22 is a block diagram illustrating functional components of an example UE, according to some embodiments.

DETAILED DESCRIPTION

Exemplary embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which examples of embodiments of inventive concepts are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of present inventive concepts to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment can be tacitly assumed to be present/used in another embodiment. Any two or more embodiments described in this document may be combined with each other.

When deciding a UE’s configuration for dual connectivity, it is necessary for the network to decide which band entries of a band combination (BC) supported by the UE to configure in the MCG and which band entries to configure in the SCG.

In EN-DC, each band combination contains a set of LTE band entries and NR band entries in a choice structure, as seen in the ASN.1 snippet below. From this structure, it is implicitly clear for each band entry in the BC whether it can be used in MCG or SCG.

. begin specification excerpt .

— ASNlSTART

— TAG-BANDCOMBINATIONLIST-START

BandCombinationList :: SEQUENCE (SIZE (1..maxBandComb))OF BandCombination

BandCombination ::= SEQUENCE { bandList SEQUENCE (SIZE (1..maxSimultaneousBands))OF BandParameters, featureSetCombination FeaturesetCombinationld, ca-ParametersEUTRA CA-ParametersEUTRA OPTIONAL, ca-ParametersNR CA-ParametersNR OPTIONAL, mrdc-Parameters MRDC-Parameters OPTIONAL, supportedBandwidthCombinationset BIT STRING (SIZE (1..32)) OPTIONAL, powerClass-vl530 ENUMERATED {pc2} OPTIONAL

BandParameters ::= CHOICE { eutra SEQUENCE { bandEUTRA FreqBandlndicatorEUTRA, ca-BandwidthClassDL-EUTRA CA-BandwidthClassEUTRA OPTIONAL, ca-BandwidthClassUL-EUTRA CA-BandwidthClassEUTRA OPTIONAL

} , nr SEQUENCE { bandNR FreqBandlndicatorNR, ca-BandwidthClassDL-NR CA-BandwidthClassNR OPTIONAL, ca-BandwidthClassUL-NR CA-BandwidthClassNR OPTIONAL

— TAG-BANDCOMBINATIONLIST-STOP

— ASNlSTOP end specification excerpt The same applies also for Release 15 (Rel-15) NR-DC, even if only NR band entries are listed in each BC. This is because Rel-15 UEs support only FR1-FR2 NR-DC, meaning that the MCG may include only band entries in FR1 and the SCG may include only band entries in FR2. From this, it is clear which band entries of each supported BC can be in MCG and SCG, respectively. However, considering now Release 16 (Rel-16) NR-DC, in which FR1 -FR1 NR-DC is also supported, it is no longer implicitly clear which band entries in a BC can be set up in MCG and SCG. Furthermore, Rel-16 introduces support of asynchronous DC, in which the synchronization between MCG and SCG is more relaxed compared to synchronous DC. For some BCs, a UE may support arbitrary grouping into MCG and SCG, but for some BCs there may be restrictions, e g., when it comes to support of synchronous or asynchronous DC. In this case, asynchronous

DC operation may only be supported between some of the band entries in the BC.

Thus, for NR-DC some additional information is needed to allow the UE to indicate how the band entries of a BC can be grouped into MCG and SCG.

In LTE-DC, a similar problem was solved by including, in the capabilities information, a bit string for each BC supported by the UE, with the bit string indicating the supported grouping of band entries into first and second cell groups, either of which could be configured as the MCG or SCG. This approach is shown in Table 1, below, which is reproduced from 3GPP TS 36.331.

This table shows the grouping of cells to the first and second cell group, as indicated by the supportedCellGrouping IE. The leading/leftmost bit of sup portedCellGrouping corresponds to the Bit String Position 1. However, this solution however does not scale well for BCs with increasing number of band entries, as the number of possible combinations increase exponentially. Thus, signaling overhead for large BCs would become substantial.

To support NR-DC, capability information for UEs can be modified to address the problems discussed above. Several approaches, some of which can be used together, are described in more detail below. In a first approach, a FeatureSets IE in NR can be used to indicate, per band entry, whether the corresponding band can be used in MCG/SCG, or both. This can be done, for example, by including a new field, which might be called supportedCellGrouping, per FeatureSetDownlinkAJplink , to indicate whether the associated band can be used in a first or second cell group. The grouping of a band entry in this manner limits how that band may be used in DC, such that when bands in the first cell group are configured as MCG, bands in the second cell group can only be configured as SCG. Likewise, when bands in the first cell group are configured as SCG, bands in the second cell group can only be configured as MCG. With this approach, the absence of this supportedCellGrouping field for a given band means that this band can be configured either in MCG or SCG, in some embodiments. Note, of course, that this field may have any name; the name supportedCellGrouping is just one example of a possible field name. This first approach may result in an increased number of FeatureSetDownlink/Uplink entries that are required, but if these are reused across several BCs then the additional overhead may still be smaller than the LTE DC signaling, which adds a new bit string to each BC. Note that the FeatureSets could be signaled in FeatureSetCombinationDC, such that they apply only for NR- DC

Another approach, which addresses the issue of whether the UE can support certain band combinations for asynchronous DC, which may be referred to as “async” DC herein, is to include, in the UE capabilities information, one bit per BC (e g., in CA-ParametersNRDC) to indicate support for async FR1 -FR2 NR-DC, meaning that NR-DC is supported between FR1 band entries of the BC in MCG and FR2 band entries of the BC in SCG. This optional bit can be added in addition to possible other optional indications for intra-FR NR-DC cases, e g.: one bit to indicate async NR-DC support within FR1 and one bit to indicate NR-DC support within FR2); or a cell grouping field that may be added for intra-FR NR-DC, e g., according to an approach described below. Alternatively, one bit per UE may be included, to indicate generally whether async FR1-FR2 NR-DC is supported.

In some embodiments, a new field includeNRDC-FR 1 -FR2 may be included in UE- CapabilityRequestFilterCommon of a UE capability request, allowing the network to request UE capabilities only for FR1-FR2 NR-DC, i.e., where FR1 bands are only in MCG and FR2 bands are only in SCG. This enables the UE to report only the field indicating async FR1-FR2 NR-DC for a band combination, and it can omit indicating any intra-FR NR-DC combinations it may support Note that the suggested field name includeNRDC-FR 1 -FR2 is only a suggested possibility; other names may be used for this and any other fields and information elements described herein.

Altematively, a new field includeNRDC-SameFR in UE-CapabilityRequestFilterCommon may be included in a UE capability request, allowing the network to request UE capabilities for intra- FR NR-DC band combinations. This implies that the UE only reports capabilities related to intra- FR NR-DC if the field includeNRDC-SameFR was included in the network request for UE capabilities. In this case, if the network requests UE capabilities for NR-DC in general (e g., by including includeNR-DC in UE-CapabilityRequestFilterCommon) but does not include the new field ( includeNRDC-SameFR ), the UE explicitly indicates support for async FR1 -FR2 NR-DC for a band combination.

This approach may be combined with the one above - which implies that async FR1-FR2 NR- DC capabilities and async intra-FR NR-DC capabilities are only reported if the fields includeNRDC-FRl-FR2 and includeNRDC-SameFR, respectively, are present in the network request for UE capabilities.

Another approach to addressing the problems described herein is to adopt the LTE-DC approach (cell grouping), while allowing it to be reported in a band combination with more band entries than the number of entries the UE supports for async NR-DC. The limit could be, for example, 4 or 5. This can be combined with the approach described above for signaling async NR-DC support, such that, for example:

• A single bit is used to indicate support for async FR1 -FR2 NR-DC for a band combination, and

• Cell grouping is used to indicate support for async intra-FR NR-DC for a band combination.

These solutions can greatly reduce signaling size for UE capabilities when reporting support for async NR-DC, while also reducing the complexity of parsing such capabilities on the network side.

Following are detailed examples of how the approaches described above may be implemented. Unless explicitly indicated or it is clear from the context, two or more of these approaches, or any parts of them, may be combined.

An example of how the first approach described above could be implemented in the specifications for NR RRC, in 3GPP TS 38.331, is provided first Note the supportedCellGrouping field in the FeatureSetDownlink IE definitions. A similar structure can be used for the FeatureSetUplink definition.

— begin proposed specification excerpt —

Feature Sets The IE FeatureSets is used to provide pools of downlink and uplink features sets. A FeatureSetCombination refers to the IDs of the feature set(s) that the UE supports in that FeatureSetCombination. The BandCombination entries in the BandCom binationList then indicate the ID of the FeatureSetCombination that the UE supports for that band combination.

The entries in the lists in this IE are identified by their index position. For example, the FeatureSetUplinkPerCC-Id = 4 identifies the fourth element in the featureSetsUplinkPerCC list.

NOTE: When feature sets (per CC) IEs require extension in future versions of the specification, new versions of the FeatureSetDownlink, FeatureSetUplink, FeatureSets, FeatureSetDownlinkPerCC and/or FeatureSetUplinkPerCC will be created and instantiated in corresponding new lists in the FeatureSets IE. For example, if new capability bits are to be added to the FeatureSetDownlink, they will instead be defined in a new FeatureSetDownlink-rxy which will be instantiated in a new featureSetDownlinkList- rxy list. If a UE indicates in a FeatureSetCombination that it supports the FeatureSetDownlink with ID #5, it implies that it supports both the features in FeatureSetDownlink #5 and FeatureSetDownlink-rxy #5 (if present). The number of entries in the new list(s) shall be the same as in the original list(s).

FeatureSets information element

— ASN1START

— TAG-FEATURESETS-START

FeatureSets ::= SEQUENCE { featureSetsDownlink SEQUENCE (SIZE (1. .maxDownlinkFeatureSets))OF FeaturesetDownlink OPTIONAL, featureSetsDownlinkPerCC SEQUENCE (SIZE (1..maxPerCC-FeatureSets))OF FeaturesetDownlinkPerCC OPTIONAL, featureSetsUplink SEQUENCE (SIZE (1..maxUplinkFeatureSets))OF FeaturesetUplink OPTIONAL, featureSetsUplinkPerCC SEQUENCE (SIZE (1..maxPerCC-FeatureSets))OF FeaturesetUplinkPerCC OPTIONAL, featureSetsDownlink-vl540 SEQUENCE (SIZE (1..maxDownlinkFeatureSets))OF FeaturesetDownlink-vl540 OPTIONAL, featureSetsUplink-vl540 SEQUENCE (SIZE (1..maxUplinkFeatureSets))OF FeatureSetUplink-vl540 OPTIONAL, featureSetsUplinkPerCC-vl540 SEQUENCE (SIZE (1..maxPerCC-FeatureSets))OF FeatureSetUplinkPerCC-vl540 OPTIONAL ]] , featureSetsDownlink-vl6xy SEQUENCE (SIZE (1..maxDownlinkFeatureSets))OF FeatureSetDownlink-vl6xy OPTIONAL ]]

— TAG-FEATURESETS-STOP

— ASNlSTOP

FeatureSetDownlink

The IE FeatureSetDownlink indicates a set of features that the UE supports on the carriers corresponding to one band entry in a band combination. FeatureSetDownlink Information element

— ASNlSTART

— TAG-FEATURESETDOWNLINK-START FeatureSetDownlink SEQUENCE { featureSetListPerDownlinkCC SEQUENCE (SIZE (1..maxNrofServingCells))OF

FeatureSetDownlinkPerCC-Id, lntraBandFreqSeparationDL FreqSeparationClass

OPTIONAL, scalingFactor ENUMERATED (f0p4, f0p7S, f0p8)

OPTIONAL, crossCarrierScheduling-OtherSCS ENUMERATED (supported)

OPTIONAL, scellWithoutSSB ENUMERATED (supported)

OPTIONAL, csi-RS-MeasSCellWithoutSSB ENUMERATED (supported)

OPTIONAL, dummyl ENUMERATED (supported)

OPTIONAL, typel-3-CSS ENUMERATED (supported)

OPTIONAL, pdcch-MonitoringAnyOccasions ENUMERATED (withoutDCI-Gap,withDCI-Gap)

OPTIONAL, dummy2 ENUMERATED (supported)

OPTIONAL, ue-SpecificUL-DL-Assignment ENUMERATED (supported) OPTIONAL, searchSpaceSharingCA-DL ENUMERATED (supported)

OPTIONAL, timeDurationForQCL SEQUENCE ( scs-60kHz ENUMERATED (s7, s!4, s28)

OPTIONAL, scs-120kHz ENUMERATED (s!4, s28) OPTIONAL

)

OPTIONAL, pdsch-ProcessingTypel-DifferentTB-PerSlot SEQUENCE ( scs-15kHz ENUMERATED (upto2, upto4, upto7) OPTIONAL, scs-30kHz ENUMERATED (upto2, upto4, upto7)

OPTIONAL, scs-60kHz ENUMERATED (upto2, upto4, upto7)

OPTIONAL, scs-120kHz ENUMERATED (upto2, upto4, upto7)

OPTIONAL

)

OPTIONAL, dummyS DunmyA

OPTIONAL, dummy4 SEQUENCE (SIZE (1..maxNrofCodebooks))OF DummyB

OPTIONAL, dummyS SEQUENCE (SIZE (1..maxNrofCodebooks))OF DuranyC

OPTIONAL, dummy6 SEQUENCE (SIZE (1..maxNrofCodebooks))OF DuranyD

OPTIONAL, dummy7 SEQUENCE (SIZE (1..maxNrofCodebooks))OF DummyE

OPTIONAL

)

FeatureSetDownlink-vl540 SEQUENCE ( oneFL-DMRS-TwoAdditionalDMRS-DL ENUMERATED (supported) OPTIONAL, additionalDMRS-DL-A1t ENUMERATED (supported) OPTIONAL, twoFL-DMRS-TwoAdditionalDMRS-DL ENUMERATED (supported) OPTIONAL, oneFL-DMRS-ThreeAdditionalDMRS-DL ENUMERATED (supported) OPTIONAL, pdcch-MonitoringAnyOccasionsWithSpanGap SEQUENCE ( scs-15kHz ENUMERATED {setl, set2 set3}

OPTIONAL, scs-30kHz ENUMERATED {setl, set2 set3}

OPTIONAL, scs-60kHz ENUMERATED {setl, set2 set3}

OPTIONAL, scs-120kHz ENUMERATED {setl, set2 set3}

OPTIONAL

OPTIONAL, pdsch-SeparationWithGap ENUMERATED {supported}

OPTIONAL, pdsch-ProcessingType2 SEQUENCE { scs-15kHz ProcessingParameters OPTIONAL, scs-30kHz ProcessingParameters

OPTIONAL, scs-60kHz ProcessingParameters

OPTIONAL

}OPTIONAL, pdsch-ProcessingType2-Limited SEQUENCE { differentTB-PerSlot-SCS-30kHz ENUMERATED {uptol, upto2, upto4, upto7} }OPTIONAL, dl-MCS-TableAlt-Dynamiclndication ENUMERATED {supported} OPTIONAL

FeatureSetDownlink-vl6xy ::= SEQUENCE supportedCellGrouping ENUMERATED {first, second} OPTIONAL

DummyA ::= SEQUENCE { maxNumberNZP-CSI-RS-PerCC INTEGER (1..32), maxNumberPortsAcrossNZP-CSI-RS-PerCC ENUMERATED {p2,p4,p8,pl2,pl6,p24,p32,p40 p48,p56,p64,p72,p80, p88,p96,pl04,pll2,pl20,pl28, pl36,pl44,pl52,pl60,pl68, pl76,pl84,pl92,p200,p208,p216, p224,p232,p240,p248,p256}, maxNumberCS-IM-PerCC ENUMERATED {nl, n2, n4, n8, nl6, n32}, maxNumberSimultaneousCSI-RS-ActBWP-AllCC ENUMERATED {n5, n6, n7,n8, n9, nlO, nl2, nl4, nl6, nl8, n20, n22, n24, n26, n28, n30,n32, n34, n36, n38, n40, n42,n44, n46, n48, n50,n52, n54, n56,n58, h60, n62, n64}, totalNumberPortsSimultaneousCSI-RS-ActBWP-AllCC ENUMERATED {p8,pl2,pl6,p24,p32,p40,p48, p56,p64,p72,p80, p88,p96,pi04,pll2,pl20,pl28, p!36,p!44,p!52,pl60,pl68, p176,pi84,pl92,p200,p208, p216,p224,p232,p240,p248,p256}

DummyB ::= SEQUENCE { maxNumberTxPortsPerResource ENUMERATED {p2,p4,p8,pl2,p16,p24,p32}, maxNumberResources INTEGER (1..64), totalNumberTxPorts INTEGER (2..256), supportedCodebookMode ENUMERATED {model,modelAndMode2}, maxNumberCSI-RS-PerResourceSet INTEGER (1..8)

DummyC ::= SEQUENCE { maxNumberTxPortsPerResource ENUMERATED {p8,pl6,p32}, maxNumberResources INTEGER (1..64), totalNumberTxPorts INTEGER (2..256), supportedCodebookMode ENUMERATED {model,mode2,both}, supportedNumberPanels ENUMERATED {n2, n4}, maxNumberCSI-RS-PerResourceSet INTEGER (1..8) DummyD ::= SEQUENCE ( maxNumberTxPortsPerResource ENUMERATED {p4,p8,pl2,pl6,p24,p32}, maxNumberResources INTEGER (1..64), totalNumberTxPorts INTEGER (2..256), parameterLx INTEGER (2..4), amplitudeScalingType ENUMERATED {wideband,widebandAndSubband}, amplitudeSubsetRestriction ENUMERATED {supported} OPTIONAL maxNumberCSI-RS-PerResourceSet INTEGER (1..8)

DummyE ::= SEQUENCE { maxNumberTxPortsPerResource ENUMERATED {p4,p8,pl2,rΐb,p24,p32}, maxNumberResources INTEGER (1..64), totalNumberTxPorts INTEGER (2..256), parameterLx INTEGER (2..4), amplitudeScalingType ENUMERATED {wideband,widebandAndSubband}, maxNumberCSI-RS-PerResourceSet INTEGER (1..8)

— TAG-FEATURESETDOWNLINK-STOP

— ASNlSTOP

end proposed specification excerpt

In the example above, the absence of the field supportedCellGrouping in a FeatureSetDownlink or FeatureSetUplink associated with a given band entry may be interpreted as meaning that the band entry can be configured in either an MCG or SCG. As an alternative to how the field supportedCellGrouping is defined in the above example, the new field could have the values first, second or both, allowing an explicit indication that the band entry can be configured either as MCG or SCG. An example of this is provided below:

. begin proposed specification excerpt .

FeatureSetDownlink-vl6xy ::= SEQUENCE { suppertedCellGrouping ENUMERATED (first, second,both) OPTIONAL

) supportodCollQrouplng

Indicates the supported cell group (first second or both) of the band entry associated with this FeotureSetDownlink in NR- DC When bands in the first cell group are configured as MCG, bands in the second cell group can only be configured as SCG. When bands in the first cell group are configured as SCG, bands in the second cell group can only be configured as MCG. The value both means the band entry associated with this FeotureSetDownlink can be used in either MCG or SCG.

— end proposed specification excerpt —

Below is an example of how the second approach described above, for indicating whether the UE can support certain band combinations for async DC, could be implemented in NR RRC, in 3GPP TS 38.331. Note the asyncNRDC-FRl-FR2 field in the CA-ParametersNRDC field descriptions, as well as the incIudeNRDC-FR 1 -FR2 field in the UE- CapabilityRequestFilterCommon field description.

— begin proposed specification excerpt —

CA-ParametersNR

The IE CA-ParametersNR contains carrier aggregation related capabilities that are defined per band combination.

CA-ParametersNR Information element

— ASNlSTART

— TAG-CA-PARAMETERSNR-START

CA-ParametersNR ::- SEQUENCE ( dummy ENUMERATED (supported) OPTIONAL, parallelTxSRS-PUCCH-PUSCH ENUMERATED (supported) OPTIONAL, parallelTxPRACH-SRS-PUCCH-PUSCH ENUMERATED (supported) OPTIONAL, slmultaneousRxTxInterBandCA ENUMERATED (supported) OPTIONAL, slmultaneousRxTxSUL ENUMERATED (supported) OPTIONAL, diffNumerologyAcrossPUCCH-Group ENUMERATED (supported) OPTIONAL, diffNumerologyWithinPUCCH-GroupSmallerSCS ENUMERATED (supported) OPTIONAL, suppertedNumberTAG ENUMERATED (n2, n3,n4) OPTIONAL,

)

CA-ParametersNR-vl540 SEQUENCE ( simultaneousSRS-AssocCSI-RS-AllCC INTEGER (5..32) OPTIONAL, csi-RS-IM-ReceptionForFeedbackPerBandComb SEQUENCE ( maxNumberSlmultaneousNZP-CSI-RS-ActBWP-AllCC INTEGER (1..64) OPTIONAL, totalNumberPortsSlmultaneousNZP-CSI-RS-ActBWP-AllCC INTEGER (2..256) OPTIONAL

) OPTIONAL, simultaneousCSI-ReportsAllCC INTEGER (5..32) OPTIONAL, dualPA-Architecture ENUMERATED (supported) OPTIONAL

) CA-ParametersNR-vl550 SEQUENCE { dummy ENUMERATED (supported) OPTIONAL

)

CA-ParametersNR-vl560 SEQUENCE ( diffNumerologyWithinPUCCH-GroupLargerSCS ENUMERATED (supported) OPTIONAL

)

— TAG-CA-PARAMETERSNR-STOP

— ASN1ST0P

CA-ParametersNRDC The IE CA-ParametersNRDC contains dual connectivity related capabilities that are defined per band combination.

CA-ParametersNRDC Information element

— ASNlSTART

— TAG-CA-PARAMETERS-NRDC-START

CA-ParametersNRDC ::- SEQUENCE ( ca-ParametersNR-ForDC CA-ParametersNR OPTIONAL, ca-ParametersNR-ForDC-vl540 CA-ParametersNR-vl540 OPTIONAL, ca-ParametersNR-ForDC-vl550 CA-ParametersNR-vl550 OPTIONAL, ca-ParametersNR-ForDC-vl560 CA-ParametersNR-vl560 OPTIONAL, featureSetCombinationDC FeatureSetCombinatlonld OPTIONAL

)

CA-ParametersNRDC-vl6xy SEQUENCE ( asyncNRDC-FRl-FR2 ENUMERATED (supported) OPTIONAL,

)

— TAG-CA-PARAMETERS-NRDC-STOP

— ASN1STOP

CA-PanmvtorsNRDC field descriptions ca-ParamatwsNR-forDC (with and without suffix)

If this field Is present for a band combination, It reports the UE capabilities when NR-DC Is configured with the band combination. If no version of this field (l.e, with and without suffix) Is present for a band combination, the ca- ParametersNR field versions (with and without suffix) In BandComblnaOon are applicable to the UE configured with NR-DC for the band combination. foatunSetCombJnalionDC

If this field Is present for a band combination, It reports the feature set combination supported for the band combination when NR-DC Is configured. If this field Is absent for a band combination, the featureSetCombinatton In BandComblnatton (without suffix) Is applicable to the UE configured with NR-DC for the band combination. asyncNRDC-FR1-FR2

If this field Is present for a band combination, It reports that asynchronous NR-DC operation as defined In [ref] Is supported between FR1 band entries of the BC In MCG and FR2 band entries of the BC In SCG.

UE-CapabilityRequestFilterCommon

The IE UE-CapabilityRequestFilterCommon is used to request filtered UE capabilities. The filter is common for all capability containers that are requested. UE-CapabilityRequestFilterCommon information element

— ASNlSTART

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-START UE-CapabilityRequestFilterCommon :: SEQUENCE ( mrdc-Request SEQUENCE ( omitEN-DC ENUMERATED (true)

OPTIONAL, — Need N includeNR-DC ENUMERATED (true) OPTIONAL, — Need N includeNE-DC ENUMERATED (true) OPTIONAL — Need N

OPTIONAL,

— Need N

[ [ includeNRDC-FRl-FR2-vl6xy ENUMERATED (true) OPTIONAL

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-STOP — ASN1STOP

. end proposed specification excerpt .

Alternatively, a new field includeNRDC-SameFR can be introduced, so that the UE capabilities for async FR1-FR2 NR-DC are always reported (if includeNR-DC is present) but the ones for intra-FR NR-DC are only reported if includeNRDC-SameFR is present. This approach could also be combined with the one above - which would imply that async FR1 -FR2 NR-DC capabilities and async intra-FR NR-DC capabilities are only reported if the fields includeNRDC-FRl-FR2 and includeNRDC-SameFR, respectively, are present in the network request for UE capabilities.

An example according to this approach is shown below. Note the includeNR-DC and includeNRDC-SameFR fields in the field descriptions. . begin proposed specification excerpt . UE-CapabilityRequestFilterCommon

The IE UE-CapabilityRequestFilterCommon is used to request filtered UE capabilities. The filter is common for all capability containers that are requested.

UE-CapabilityRequestFilterCommon information element

— ASNlSTART

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-START

UE-CapabilityRequestFilterCommon :: SEQUENCE { mrdc-Request SEQUENCE { omitEN-DC ENUMERATED {true}

OPTIONAL, — Need N includeNR-DC ENUMERATED {true}

OPTIONAL, — Need N includeNE-DC ENUMERATED {true}

OPTIONAL — Need N

OPTIONAL

— Need N [[ includeNRDC-SameFR-vl6xy ENUMERATED {true} OPTIONAL

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-STOP

— ASNlSTOP

. end proposed specification excerpt .

Yet another alternative is to add instead a field, e.g., an omitNRDC-FRl-FR2 field, to instruct the UE to omit reporting intra-FR NR-DC band and feature combinations when reporting for NR- DC. The corresponding field description could look as follows, for example:

. begin proposed specification excerpt . UE-CapabilityRequestFilterCommon

UE-CapabilityRequestFilterCommon information element

— ASNlSTART

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-START

UE-CapabilityRequestFilterCommon ::= SEQUENCE { mrdc-Request SEQUENCE { omitEN-DC ENUMERATED {true}

OPTIONAL, — Need N includeNR-DC ENUMERATED {true}

OPTIONAL, — Need N includeNE-DC ENUMERATED {true}

OPTIONAL — Need N

OPTIONAL,

— Need N [[ omitNRDC-FRl-FR2-vl6xy ENUMERATED {true} OPTIONAL

— TAG-UE-CAPABILITYREQUESTFILTERCOMMON-STOP

— ASN1STOP

_ end proposed specification excerpt

Below is an example of how the third approach described above, building upon the LTE-DC approach for cell grouping, could be implemented in NRRRC, in 3GPP TS 38.331. Here, note the supportedCellGrouping and asyncNR fields. — begin proposed specification excerpt —

CA-ParametersNRDC

The IE CA-ParametersNRDC contains dual connectivity related capabilities that are defined per band combination.

CA-ParametersNRDC Information element

— ASNlSTART

— TAG-CA-PARAMETERS-NRDC-START

CA-ParametersNRDC ::■ SEQUENCE { ca-ParametersNR-ForDC CA-ParametersNR OPTIONAL, ca-ParametersNR-ForDC-vl540 CA-ParametersNR-vl540 OPTIONAL, ca-ParametersNR-ForDC-vl550 CA-ParametersNR-vlSSO OPTIONAL, ca-ParametersNR-ForDC-vl560 CA-ParametersNR-vlseO OPTIONAL, featureSetComblnatlonDC FeatureSetCombinationld OPTIONAL )

CA-ParametersNRDC-vl6xy SEQUENCE { suppertedCellGrouping CHOICE ( threeEntries-rl6 BIT STRING <SIZE<3)),

£ourEntries-rl6 BIT STRING (SIZE(7)),

£iveEntries-rl6 BIT STRING (SIZE(IS))

I OPTIONAL

I

— TAG-CA-PARAMBTERS-NRDC-STOP

— ASN1STOP

CA-ParamatarsNRDC field description» ca-ParamatwsNR-forDC (with and without suffix)

If this field Is present for a band combination, It reports the UE capabilities when NR-DC Is configured with the band combination. If no version of this field (i.e., with and without suffix) Is present for a band combination, the ca- ParametersNR field versions (with and without suffix) In BandComblnaOon are applicable to the UE configured with NR-DC for the band combination. foatunSetCombJnalionDC

If this field Is present for a band combination, It reports the feature set combination supported for the band combination when NR-DC Is configured. If this field Is absent for a band combination, the featureSetCombinatton In BandComblnatton (without suffix) Is applicable to the UE configured with NR-DC for the band combination. supportadCallQrouplng

This field Indicates for which mapping of serving cells to cell groups (I.e. MCG or SCG) the UE supports asynchronous NR-DC. If this field Is not present but asynchronous operation Is supported (by Including asyncNRDC), the UE supports all possible mappings of serving cells to cell groups for the band combination. The bitmap size Is selected based on the number of entries the UE supports asynchronous NR-DC, I.e., In case of three entries, the bitmap corresponding to threeEntries Is selected and so on.

A bit In the bit string set to 1 1ndicates that the UE supports asynchronous DC for the cell grouping option represented by the concerned bit position. Each bit position represents a different cell grouping option, as Illustrated by a table, see NOTE 5. A cell grouping option Is represented by a number of bits, each representing a particular band entry In the band combination with the left-most bit referring to the band listed first In the band combination, etc. Value 0 Indicates that the carriers of the corresponding band entry are mapped to a first cell group, while value 1 1ndicates that the carriers of the corresponding band entry are mapped to a second cell group. It Is noted that the mapping table does not Include entries with all bits set to the same value (0 or 1) as this does not represent a DC scenario (I.e. Indicating that the UE supports that all carriers of the corresponding band entry are In one cell group).

It Is also noted that the number of band entries In a band combination can be higher than the number of entries Indicated In supportedCellGrouplng, which Implies that the UE does not support ansynchronous NR-DC for the remaining band entries In the band combination that cannot be signaled with suppoitedCeUGrouping.

NOTE : The grouping of the cells to the first and second cell group, as indicated by supportedCellGrouping, is shown in the table below. The leading / leftmost bit of supportedCellGrouping corresponds to the Bit String Position 1.

Nr of Band Entries: 5 4 3

Length of Bit-String: 15 7 3

Cell grouping option (0· first cell group, 1· second cell

Bit String Position group)

1 00001 0001 001

2 00010 0010 010

3 00011 0011 011

4 00100 0100

5 00101 0101

6 00110 0110

7 00111 0111

8 01000

9 01001

10 01010

11 01011

12 01100

13 01101

14 01110

15 01111

CA-ParametersNRDC

CA-ParametersNRDC Information element

— ASNlSTART

— TAG-CA-PARAMBTERS-NRDC-START

CA-ParametersNRDC ::■ SEQUENCE { ca-ParametersNR-ForDC CA-ParametersNR OPTIONAL, ca-ParametersNR-ForDC-vl540 CA-ParametersNR-vl540 OPTIONAL, ca-ParametersNR-ForDC-vl550 CA-ParametersNR-vl550 OPTIONAL, ca-ParametersNR-ForDC-vl560 CA-ParametersNR-vl560 OPTIONAL, featureSetCombinationDC FeatureSetCombinationld OPTIONAL

)

CA-ParametersNRDC-vl6xy SEQUENCE { asyncNRDC ENUMERATED (supported) OPTIONAL,

I

— TAG-CA-PARAMBTERS-NRDC-STOP

— ASN1STOP

. end proposed specification excerpt .

In the above, the bit asyncNRDC represents UE support, for a specific band combination, of NR- DC asynchronous in general, i.e., for both FR1-FR2 NR-DC and intra-FR NR-DC, while supportedCellGrouping (if present) indicates, for a specific band combination, which MCG and SCG configurations the UE supports in case of asynchronous NR-DC.

Alternatively, there could be different bits for specific NR-DC cases, as was described in the second approach, above. For instance, there could be one bit to represent support of asynchronous NR-DC between FR1 band entries of the BC in MCG and FR2 band entries of the BC in SCG, while another bit would represent support of intra-FR NR-DC.

Moreover, supportedCellGrouping can be specific to one of the NR-DC cases. For instance, supportedCellGrouping could be defined to only indicate support of intra-FR NR-DC; in this manner, e.g., for asynchronous intra-FRl NR-DC, the entries indicated in supportedCellGrouping would refer to the FR1 entries within the band combination. Figure 11 is a flowchart illustrating an example method 1100 for reporting capability information for a UE, consistent with any or all of the above techniques. Method 1100 may be carried out by a base station, such as a gNB or eNB, in various embodiments, or by the UE, in other embodiments.

Method 1100 includes the step of indicating, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group (MCG), a secondary cell group (SCG), or both. This is shown at block 1110. In some embodiments, this comprises indicating whether each band in the band combination can be used in a first cell group or a second cell group, such that one or more bands in the band combination are indicated as being in the first cell group and one or more other bands in the band combination are indicated as being in the second cell group. In some of these embodiments, this is done by identifying a particular FeatureSetDownlink and/or a particular FeatureSetUplink for each band in the band combination, the identified FeatureSetDownlink and/or FeatureSetUplink for each of one or more bands in the band combination comprising a field indicating whether the band for which the Feature SetDownlink and/or FeatureSetUplink is identified can be used in the first cell group or the second cell group. This field may be a supportedCellGrouping field, as described above. In some of these embodiments, the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination does not include a field indicating whether the corresponding band can be used in the first cell group or the second cell group, and this omission indicates that the corresponding band can be grouped in either the first cell group or the second cell group. In some other embodiments, the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination indicates that the corresponding band can be grouped in either the first cell group or the second cell group.

In some embodiments, the method further comprises the step of including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1120. Block 1120 and several other blocks in the process flow diagrams of Figures 11 and 12 are illustrated with a dashed outline to indicate that the illustrated step might not be present in every embodiment or instance of the illustrated method. Similarly, the method may further comprise including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR1 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1130. Likewise, the method may further comprise including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR2-FR2 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1140. The method may further comprise including, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous intra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC. This is shown at block 1150. In some embodiments, the method may comprise receiving a request for the message reporting capabilities, as shown at block 1105, in which case the step of block 1110 may comprise sending the message reporting capabilities in response to the request. In some embodiments, this request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR- DC, for one or more band combinations supported by the UE, e g., an includeNRDC-FRl-FR2 as described above. In some of these embodiments, the method further comprises including, in response to this request, only asynchronous FR1-FR2 NR-DC support for a band combination and omitting any intra-FR NR-DC support for the band combination.

In some other embodiments, the request may comprise a field indicating that the message should indicate UE capabilities for intra-FR NR-DC, for one or more band combinations supported by the UE, e g. , an includeNRDC-SameFR field as described above.

In some embodiments where the method 1100 is carried out by a UE, the method may further comprise receiving, from a network node, configuration information configuring the UE for dual connectivity in accordance with the capabilities reported in the message. This is shown at block 1160. In some embodiments and/or instances where the method is carried out by a base station, the message may be received from an MME or other core network element, e g., in association with a handoff. In other embodiments and/or instances, the message may be received from the UE, e g., in response to a request as discussed above.

Figure 12 is a flowchart illustrating an example method 1200, which is a counterpart method for handling capability information for a UE, consistent with any or all of the above techniques. Method 1200 may be carried out by a base station, for example, such as a gNB or eNB, in various embodiments.

Method 1200 includes the step of receiving, in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. This is shown at block 1210. In some embodiments, this information indicates whether each band in the band combination can be used in a first cell group or a second cell group, such that one or more bands in the band combination are indicated as being in the first cell group and one or more other bands in the band combination are indicated as being in the second cell group. In some of these embodiments, this is done by identifying a particular FeatureSetDownlink and/or a particular FeatureSetUplink for each band in the band combination, the identified FeatureSetDownlink and/or FeatureSetUplink for each of one or more bands in the band combination comprising a field indicating whether the band for which the Feature SetDownlink and/or FeatureSetUplink is identified can be used in the first cell group or the second cell group. This field may be a supportedCellGrouping field, as described above.

In some of these embodiments, the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination does not include a field indicating whether the corresponding band can be used in the first cell group or the second cell group, and this omission indicates that the corresponding band can be grouped in either the first cell group or the second cell group. In some other embodiments, the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination indicates that the corresponding band can be grouped in either the first cell group or the second cell group.

In some embodiments, the method further comprises the step of receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1 -FR2 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1220. Similarly, the method may further comprise receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1- FR1 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1230. Likewise, the method may further comprise receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR2-FR2 NR-DC is supported by the UE for the corresponding band combination. This is shown at block 1240. The method may further comprise receiving, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous intra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC. This is shown at block 1250.

In some embodiments, the method may comprise sending a request for the message reporting capabilities, as shown at block 1205, in which case the step of block 1210 may comprise receiving the message reporting capabilities in response to the request. In some embodiments, this request comprises a field indicating that the message should indicate UE capabilities for FR1 -FR2 NR-DC, for one or more band combinations supported by the UE, e g., an includeNRDC-FRl -FR2 field as described above. In some of these embodiments, the message received in response to the request may include only asynchronous FR1 -FR2 NR-DC support for a band combination and omit any intra-FR NR-DC support for the band combination. In some embodiments, the request may comprise a field indicating that the message should indicate UE capabilities for intra-FR NR-DC, for one or more band combinations supported by the UE, e g., an includeNRDC-SameFR field as described above. In some embodiments, the method may further comprise configuring the UE for dual connectivity, based on the capabilities reported in the message. This is shown at block 1260.

Figure 13 shows a network node 30, which may be configured to carry out all or parts of one or more of these disclosed techniques. More particularly, network node 30, which in the illustrated example is a radio network node (because it includes a radio for communicating with one or more UEs), such as a gNB or eNB, may perform those operations attributed in the above discussion to a network node. In particular, network node 30 may carry out a method according to Figure 11 and/or Figure 12, in various embodiments.

Network node 30 may be an evolved Node B (eNodeB), Node B or gNB. While a radio network node 30 is shown in Figure 13, the operations can be performed by other kinds of network nodes, including a radio network node such as base station, radio base station, base transceiver station, base station controller, network controller, NR base station (BS), Multi-cell/multicast Coordination Entity (MCE), relay node, access point, radio access point, Remote Radio Unit (RRU) Remote Radio Head (RRH), or a multi-standard BS (MSR BS). Network node 30 may also, in some cases, be a core network node (e g., MME, SON node, a coordinating node, positioning node, MDT node, etc ), or even an external node (e g., 3rd party node, a node external to the current network), etc. Network node 30 may also comprise test equipment.

Network node 30 facilitates communication between wireless terminals (e g., UEs), other network access nodes and/or the core network. Network node 30 may include communication interface circuitry 38 that includes circuitry for communicating with other nodes in the core network, radio nodes, and/or other types of nodes in the network for the purposes of providing data and/or cellular communication services. Some embodiments of network node 30 communicate with wireless devices using antennas 34 and transceiver circuitry 36. Some of these and some other embodiments may communicate with one or more relay nodes using antennas 34 and transceiver circuitry 36, e g., using antennas 34 and transceiver circuitry 36 to communicate with an MT part of a relay node. Transceiver circuitry 36 may include transmitter circuits, receiver circuits, and associated control circuits that are collectively configured to transmit and receive signals according to a radio access technology, for the purposes of providing cellular communication services. Network node 30 also includes one or more processing circuits 32 that are operatively associated with the transceiver circuitry 36 and, in some cases, the communication interface circuitry 38. Processing circuitry 32 comprises one or more digital processors 42, e g., one or more microprocessors, microcontrollers, Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), Complex Programmable Logic Devices (CPLDs), Application Specific Integrated Circuits (ASICs), or any mix thereof. More generally, processing circuitry 32 may comprise fixed circuitry, or programmable circuitry that is specially configured via the execution of program instructions implementing the functionality taught herein, or some mix of fixed and programmed circuitry. Processor 42 may be multi-core, i.e., having two or more processor cores utilized for enhanced performance, reduced power consumption, and more efficient simultaneous processing of multiple tasks.

Processing circuitry 32 also includes a memory 44. Memory 44, in some embodiments, stores one or more computer programs 46 and, optionally, configuration data 48. Memory 44 provides non-transitory storage for the computer program 46 and it may comprise one or more types of computer-readable media, such as disk storage, solid-state memory storage, or any mix thereof. Here, “non-transitory” means permanent, semi-permanent, or at least temporarily persistent storage and encompasses both long-term storage in non-volatile memory and storage in working memory, e g., for program execution. By way of non-limiting example, memory 44 comprises any one or more of SRAM, DRAM, EEPROM, and FLASH memory, which may be in processing circuitry 32 and/or separate from processing circuitry 32. Memory 44 may also store any configuration data 48 used by the network access node 30. Processing circuitry 32 may be configured, e g., through the use of appropriate program code stored in memory 44, to carry out one or more of the methods and/or signaling processes detailed herein.

Processing circuitry 32 of the network node 30 is configured, according to some embodiments, to perform all or part of the techniques described herein for one or more network nodes of a wireless communication system, including, for example, the methods described in connection with Figures 11 and 12.

Figure 14 illustrates a diagram of a UE 50 configured to carry out one or more of the disclosed techniques, according to some embodiments. UE 50 may be considered to represent any wireless devices or mobile terminals that may operate in a network, such as a UE in a cellular network. Other examples may include a communication device, target device, device to device (D2D) UE, machine type UE or UE capable of machi ne-to-machi ne communication (M2M), a sensor equipped with UE, PDA (personal digital assistant), tablet, IPAD tablet, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), etc.

UE 50 is configured to communicate with a network node or base station in a wide-area cellular network via antennas 54 and transceiver circuitry 56. Transceiver circuitry 56 may include transmitter circuits, receiver circuits, and associated control circuits that are collectively configured to transmit and receive signals according to multiple radio access technologies, for the purposes of using cellular communication services. The radio access technologies can be NR and LTE for the purposes of this discussion.

UE 50 also includes one or more processing circuits 52 that are operatively associated with the radio transceiver circuitry 56. Processing circuitry 52 comprises one or more digital processing circuits, e g., one or more microprocessors, microcontrollers, DSPs, FPGAs, CPLDs, ASICs, or any mix thereof. More generally, processing circuitry 52 may comprise fixed circuitry, or programmable circuitry that is specially adapted via the execution of program instructions implementing the functionality taught herein or may comprise some mix of fixed and programmed circuitry. Processing circuitry 52 may be multi-core. Processing circuitry 52 also includes a memory 64. Memory 64, in some embodiments, stores one or more computer programs 66 and, optionally, configuration data 68. Memory 64 provides non-transitory storage for computer program 66 and it may comprise one or more types of computer-readable media, such as disk storage, solid-state memory storage, or any mix thereof. By way of non-limiting example, memory 64 comprises any one or more of SRAM, DRAM, EEPROM, and FLASH memory, which may be in processing circuitry 52 and/or separate from processing circuitry 52. Memory 64 may also store any configuration data 68 used by UE 50. Processing circuitry 52 may be configured, e g., through the use of appropriate program code stored in memory 64, to carry out one or more of the methods and/or signaling processes discussed above, including those discussed in connection with Figure 11. Processing circuitry 52 of the UE 50 is configured, according to some embodiments, to perform any methods that support or correspond with the techniques described herein for the network nodes or base station.

Figure 15, according to some embodiments, illustrates a communication system that includes a telecommunication network 1610, such as a 3GPP-type cellular network, which comprises an access network 1611, such as a radio access network, and a core network 1614. The access network 1611 comprises a plurality of base stations 1612a, 1612b, 1612c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 1613a, 1613b, 1613c. Each base station 1612a, 1612b, 1612c is connectable to the core network 1614 over a wired or wireless connection 1615. A first UE 1691 located in coverage area 1613c is configured to wirelessly connect to, or be paged by, the corresponding base station 1612c. A second UE 1692 in coverage area 1613a is wirelessly connectable to the corresponding base station 1612a. While a plurality of UEs 1691, 1692 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 1612. The telecommunication network 1610 is itself connected to a host computer 1630, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 1630 may be under the ownership or control of a service provider or may be operated by the service provider or on behalf of the service provider. The connections 1621, 1622 between the telecommunication network 1610 and the host computer 1630 may extend directly from the core network 1614 to the host computer 1630 or may go via an optional intermediate network 1620. The intermediate network 1620 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 1620, if any, may be a backbone network or the Interet; in particular, the intermediate network 1620 may comprise two or more sub-networks (not shown).

The communication system of Figure 15 enables connectivity between one of the connected UEs 1691, 1692 and the host computer 1630. The connectivity may be described as an over-the-top (OTT) connection 1650. The host computer 1630 and the connected UEs 1691, 1692 are configured to communicate data and/or signaling via the OTT connection 1650, using the access network 1611 , the core network 1614, any intermediate network 1620 and possible further infrastructure (not shown) as intermediaries. The OTT connection 1650 may be transparent in the sense that the participating communication devices through which the OTT connection 1650 passes are unaware of routing of uplink and downlink communications. For example, a base station 1612 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 1630 to be forwarded (e g., handed over) to a connected UE 1691. Similarly, the base station 1612 need not be aware of the future routing of an outgoing uplink communication originating from the UE 1691 towards the host computer 1630.

Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Figure

16.

In a communication system 1700, a host computer 1710 comprises hardware 1715 including a communication interface 1716 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 1700. The host computer 1710 further comprises processing circuitry 1718, which may have storage and/or processing capabilities. In particular, the processing circuitry 1718 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 1710 further comprises software 1711, which is stored in or accessible by the host computer

1710 and executable by the processing circuitry 1718. The software 1711 includes a host application 1712. The host application 1712 may be operable to provide a service to a remote user, such as a UE 1730 connecting via an OTT connection 1750 terminating at the UE 1730 and the host computer 1710. In providing the service to the remote user, the host application 1712 may provide user data which is transmitted using the OTT connection 1750.

The communication system 1700 further includes a base station 1720 provided in a telecommunication system and comprising hardware 1725 enabling it to communicate with the host computer 1710 and with the UE 1730. The hardware 1725 may include a communication interface 1726 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 1700, as well as a radio interface 1727 for setting up and maintaining at least a wireless connection 1770 with a UE 1730 located in a coverage area (not shown in Figure 16) served by the base station 1720. The communication interface 1726 may be configured to facilitate a connection 1760 to the host computer 1710. The connection 1760 may be direct or it may pass through a core network (not shown in Figure 16) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 1725 of the base station 1720 further includes processing circuitry 1728, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 1720 further has software 1721 stored internally or accessible via an external connection.

The communication system 1700 further includes the UE 1730 already referred to. Its hardware 1735 may include a radio interface 1737 configured to set up and maintain a wireless connection 1770 with a base station serving a coverage area in which the UE 1730 is currently located. The hardware 1735 of the UE 1730 further includes processing circuitry 1738, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 1730 further comprises software 1731, which is stored in or accessible by the UE 1730 and executable by the processing circuitry 1738. The software 1731 includes a client application 1732. The client application 1732 may be operable to provide a service to a human or non- human user via the UE 1730, with the support of the host computer 1710. In the host computer 1710, an executing host application 1712 may communicate with the executing client application 1732 via the OTT connection 1750 terminating at the UE 1730 and the host computer 1717. In providing the service to the user, the client application 1732 may receive request data from the host application 1712 and provide user data in response to the request data. The OTT connection 1750 may transfer both the request data and the user data. The client application 1732 may interact with the user to generate the user data that it provides.

It is noted that the host computer 1710, base station 1720 and UE 1730 illustrated in Figure 16 may be identical to the host computer 1630, one of the base stations 1612a, 1612b, 1612c and one of the UEs 1691, 1692 of Figure 15, respectively. This is to say, the inner workings of these entities may be as shown in Figure 16 and independently, the surrounding network topology may be that of Figure 15.

In Figure 16, the OTT connection 1750 has been drawn abstractly to illustrate the communication between the host computer 1710 and the use equipment 1730 via the base station 1720, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 1730 or from the service provider operating the host computer 1710, or both. While the OTT connection 1750 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e g., on the basis of load balancing consideration or reconfiguration of the network). The wireless connection 1770 between the UE 1730 and the base station 1720 is in accordance with the teachings of the embodiments described throughout this disclosure, such as provided by nodes such as UE 50 and network node 30, along with the corresponding methods 1200, 1300, 1400. The embodiments described herein allow IAB nodes and UEs to more efficiently respond to and react to network problems, such as the failure of a backhaul link, and more particularly provide more efficient release techniques in the event of such a failure. The teachings of these embodiments may improve the reliability, data rate, capacity, latency and/or power consumption for the network and UE 1730 using the OTT connection 1750 for emergency warning systems and thereby provide benefits such as more efficient and targeted emergency messaging that saves on network and UE resources while improving the ability of users to take safe action.

A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1750 between the host computer 1710 and UE 1730, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 1750 may be implemented in the software 1711 of the host computer 1710 or in the software 1731 of the UE 1730, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 1750 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 1711, 1731 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1750 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 1720, and it may be unknown or imperceptible to the base station 1720. Such procedures and functionalities may be known and practiced in the art In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer’s 1710 measurements of throughput propagation times, latency and the like. The measurements may be implemented in that the software 1711, 1731 causes messages to be transmitted, in particular, empty or ‘dummy’ messages, using the OTT connection 1750 while it monitors propagation times, errors etc. Figure 17 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment

The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 17 will be included in this section. In a first step 1810 of the method, the host computer provides user data. In an optional substep 1811 of the first step 1810, the host computer provides the user data by executing a host application. In a second step 1820, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 1830, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 1840, the UE executes a client application associated with the host application executed by the host computer.

Figure 18 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 18 will be included in this section. In a first step 1910 of the method, the host computer provides user data. In an optional substep (not shown), the host computer provides the user data by executing a host application. In a second step 1920, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 1930, the UE receives the user data carried in the transmission.

Figure 19 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment

The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 19 will be included in this section. In an optional first step 2010 of the method, the UE receives input data provided by the host computer. Additionally, or alternatively, in an optional second step 2020, the UE provides user data. In an optional substep 2021 of the second step 2020, the UE provides the user data by executing a client application. In a further optional substep 2011 of the first step 2010, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in an optional third substep 2030, transmission of the user data to the host computer. In a fourth step 2040 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure. Figure 20 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment.

The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 20 will be included in this section. In an optional first step 2110 of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In an optional second step 2120, the base station initiates transmission of the received user data to the host computer. In a third step 2130, the host computer receives the user data carried in the transmission initiated by the base station. As discussed in detail above, the techniques described herein, e g., as illustrated in the process flow diagrams of Figures 11 and 12, may be implemented, in whole or in part, using computer program instructions executed by one or more processors. It will be appreciated that a functional implementation of these techniques may be represented in terms of functional modules, where each functional module corresponds to a functional unit of software executing in an appropriate processor or to a functional digital hardware circuit, or some combination of both.

Figure 21 illustrates an example functional module or circuit architecture for a network node, such as network node 30, when operating according to various ones of the embodiments described herein. The functional implementation includes an indicating module 2204 for indicating, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. In some embodiments, the network node may comprise, instead of or in addition to the indicating module, a receiving module 2206 for receiving, in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. The implementation also includes a sending module 2202 for sending a request for the message. It will be appreciated that all of the variants discussed above for the method shown in Figures 11 and 12, for example, are applicable to the functional implementation shown in Figure

21. Finally, Figure 22 illustrates an example functional module or circuit architecture for a UE 50 that is operating as a donor node according to various ones of the embodiments described herein. The functional implementation includes an indicating module 2304 for indicating, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. The implementation also includes a sending module 2302 for sending a request for the message.

EXAMPLE EMBODIMENTS

In view of the detailed examples and description above, it will be appreciated that embodiments of the presently disclosed inventive techniques and apparatuses may include, but are not necessarily limited to, the following enumerated examples.

1. A method, in a node of a wireless network, for reporting capability information for a user equipment, UE, the method comprising: indicating, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. 2. The method of example embodiment 1 , wherein said indicating comprises indicating whether each band in the band combination can be used in a first cell group or a second cell group, such that one or more bands in the band combination are indicated as being in the first cell group and one or more other bands in the band combination are indicated as being in the second cell group.

3. The method of example embodiment 2, wherein said indicating comprises indicating whether band in the band combination can be used in the first cell group or the second cell group by identifying a particular FeatureSetDownlink and/or a particular FeatureSetUplink for each band in the band combination, the identified FeatureSetDownlink and/or FeatureSetUplink for each of one or more bands in the band combination comprising a field indicating whether the band for which the Feature SetDownlink and/or FeatureSetUplink is identified can be used in the first cell group or the second cell group.

4. The method of example embodiment 3, wherein the field is a supportedCellGrouping field.

5. The method of example embodiment 3 or 4, wherein the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination does not include a field indicating whether the corresponding band can be used in the first cell group or the second cell group, such omission indicating that the corresponding band can be grouped in either the first cell group or the second cell group.

6. The method of example embodiment 3 or 4, wherein the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination indicates that the corresponding band can be grouped in either the first cell group or the second cell group.

7. The method of any of example embodiments 1-6, further comprising: including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

8. The method of any of example embodiments 1-7, further comprising: including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR1 NR-DC is supported by the UE for the corresponding band combination.

9. The method of any of example embodiments 1-8, further comprising: including, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR2-FR2 NR-DC is supported by the UE for the corresponding band combination.

10. The method of any of example embodiments 1-9, further comprising: including, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous mtra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

11. The method of any of example embodiments 1-10, wherein the method comprises receiving a request for the message reporting capabilities and sending the message reporting capabilities in response to the request

12. The method of example embodiment 11, wherein the request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR-DC, for one or more band combinations supported by the UE.

13. The method of example embodiment 11 or 12, wherein the request comprises a field indicating that the message should indicate UE capabilities for mtra-FR NR-DC, for one or more band combinations supported by the UE.

14. The method of any of example embodiments 1-13, wherein the method is performed by a base station.

15. The method of any of example embodiments 1-14, wherein the method is performed by the

UE.

16. The method of example embodiment 15, wherein the method further comprises: receiving, from a network node, configuration information configuring the UE for dual connectivity in accordance with the capabilities reported in the message.

17. A method, in a node of a wireless network, for handling capability information for a user equipment, UE, the method comprising: receiving, in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both. 18. The method of example embodiment 17, wherein said information indicates whether each band in the band combination can be used in a first cell group or a second cell group, such that one or more bands in the band combination are indicated as being in the first cell group and one or more other bands in the band combination are indicated as being in the second cell group. 19. The method of example embodiment 18, wherein said information indicates whether band in the band combination can be used in the first cell group or the second cell group by identifying a particular FeatureSetDownlink and/or a particular FeatureSetUplink for each band in the band combination, the identified FeatureSetDownlink and/or FeatureSetUplink for each of one or more bands in the band combination comprising a field indicating whether the band for which the Feature SetDownlink and/or FeatureSetUplink is identified can be used in the first cell group or the second cell group.

20. The method of example embodiment 19, wherein the field is a supportedCellGrouping field.

21. The method of example embodiment 19 or 20, wherein the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination does not include a field indicating whether the corresponding band can be used in the first cell group or the second cell group, such omission indicating that the corresponding band can be grouped in either the first cell group or the second cell group.

22. The method of example embodiment 19 or 20, wherein the FeatureSetDownlink and/or FeatureSetUplink identified for at least one band in the band combination indicates that the corresponding band can be grouped in either the first cell group or the second cell group.

23. The method of any of example embodiments 17-22, further comprising: receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1 -FR2 NR-DC is supported by the UE for the corresponding band combination.

24. The method of any of example embodiments 17-23, further comprising: receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR1 NR-DC is supported by the UE for the corresponding band combination.

25. The method of any of example embodiments 17-24, further comprising: receiving, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR2-FR2 NR-DC is supported by the UE for the corresponding band combination.

26. The method of any of example embodiments 17-25, further comprising: receiving, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous mtra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

27. The method of any of example embodiments 17-26, wherein the method comprises sending a request for the message reporting capabilities and receiving the message reporting capabilities in response to the request

28. The method of any of example embodiments 17-27, wherein the method is performed by a base station.

29. The method of example embodiment 28, further comprising configuring the UE for dual connectivity operation, based on the message.

30. One or more network nodes or base stations adapted to perform the methods of any of example embodiments 1-14 and 17-29.

31. A network node or base station comprising transceiver circuitry and processing circuitry operatively associated with the transceiver circuitry and configured to perform the methods of any of example embodiments 1-14 and 17-29. 32. A computer program comprising instructions that, when executed on at least one processing circuit of a network node or base station, cause the at least one processing circuit to carry out the method according to any one of example embodiments 1-14 and 17-29.

33. A carrier containing the computer program of example embodiment 32, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

34. A user equipment, UE, adapted to perform a method according to any of example embodiments 1-13, 15, and 16.

35. A user equipment, UE, comprising transceiver circuitry and processing circuitry operatively associated with the transceiver circuitry and configured to perform the methods of any of example embodiments 1-13, 15, and 16.

36. A computer program comprising instructions that, when executed on at least one processing circuit of a user equipment, UE, cause the at least one processing circuit to carry out the method according to any one of example embodiments 1-13, 15, and 16.

37. A carrier containing the computer program of example embodiment 36, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

38. A communication system including a host computer comprising: processing circuitry configured to provide user data; and a communication interface configured to forward the user data to a cellular network for transmission to a user equipment (UE), wherein the cellular network comprises a base station having a radio interface and processing circuitry, the base station’s processing circuitry configured to perform any of the operations comprising embodiments 1-14 and 17-29.

39. The communication system of the previous embodiment further including the base station.

40. The communication system of the previous two embodiments, further including the UE. 41. The communication system of the previous three embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE’s processing circuitry is further configured to execute a client application associated with the host application. 42. A communication system including a host computer comprising a communication interface configured to receive user data originating from a transmission from a User equipment (UE) to a base station, the base station comprising a radio interface and processing circuitry configured to communicate with the base station and cooperatively perform operations of any of embodiments 1-14 and 17-29. 43. The communication system of the previous embodiment further including the base station.

44. The communication system of the previous two embodiments, further including the UE.

45. The communication system of the previous three embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application; and the UE is further configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

Many variations and modifications can be made to the embodiments without substantially departing from the principles of the present inventive concepts. All such variations and modifications are intended to be included herein within the scope of present inventive concepts. Accordingly, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the examples of embodiments are intended to cover all such modifications, enhancements, and other embodiments, which fall within the spirit and scope of present inventive concepts. Thus, to the maximum extent allowed by law, the scope of present inventive concepts is to be determined by the broadest permissible interpretation of the present disclosure including the examples of embodiments and their equivalents and shall not be restricted or limited by the foregoing detailed description. ABBREVIATIONS

5GC 5G core network

5GCN 5G core network

BC Band Combination CA Carrier Aggregation

CC Component Carrier

COM Code Division Multiplex

CG Cell group

CN Core network cp Control Plane

CQI Channel Quality Information

CRC Cyclic Redundancy Check

CSI-RS Channel State Information Reference Signal

DC Dual-connectivity DCI Downlink Control Information

DFT Discrete Fourier Transform

DM-RS Demodulation Reference Signal

EIRP Effective Isotropic Radiated Power eLTE evolved Long Term Evolution eNB evolved NodeB (a base station supporting the LTE air interface)

EN-DC E-UTRAN-NR Dual Connectivity

EPC Evolved packet core

E-UTRA Evolved Universal Terrestrial Radio Access

E-UTRAN Evolved Universal Terrestrial Radio Access Network FDM Frequency Division Multiplex

FR1 Frequency Range 1

FR2 Frequency Range 2

FSCC Feature Set Component Carrier gNB gNodeB (a base station supporting the NR air interface)

HARQ Hybrid Automatic Repeat Request

IE Information Element

LTE Long Term Evolution

MAC Medium Access Control MCG Master cell group

MeNB Master eNB

MgNB Master gNB

MME Mobility Management Entity

MN Master Node MR-DC Multi-Radio Dual Connectivity

NAS Non access stratum

NG Interface between RAN and 5GC ng-eNB eNB node connected via the NG interface to the 5GC

NE-DC NR - E-UTRAN Dual Connectivity NG-RAN RAN connected via the NG interface to the 5GC

NGEN-DC NG-RAN E-UTRA-NR Dual Connectivity (an ng-eNB that acts as a MN and one gNB that acts as a SN for a UE)

NR New Radio

NW Network OFDM Orthogonal Frequency Division Multiplex PAPR Peak to Average Power Ratio

PBCH Primary Broadcast Channel

PDCP Packet Data Convergence Protocol

PRACH Physical Random Access Channel PRB Physical Resource Block

PUCCH Physical Uplink Control Channel

PUSCH Physical Uplink Shared Channel

RAN Radio Access Network

RLC Radio Link Control RRC Radio Resource Control

SA Stand alone

SCG Secondary cell group

SeNB Secondary eNB

SgNB Secondary gNB SRB Signaling Radio Bearer

SRS Sounding Reference Signal

SS-block Synchronisation Signal Block

UCI Uplink Control Information

UE User Equipment UL Uplink

UP User plane

Claims

CLAIMS What is claimed is:

1. A method, performed by a user equipment UE, for reporting capability information for the UE, the method comprising: indicating (1110), in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both; and including (1120), in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

2. The method of claim 1, wherein FR1-FR2 NR-DC is dual connectivity, DC, with a master cell group, MCG, and a secondary cell group, SCG, that both employ NR radio access technology and where the MCG uses only frequency bands below 6 GHz and the SCG uses only frequency bands between 24.25 GHz and 52.6 GHz.

3. The method of claim 1 or 2, further comprising: including (1150), in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous intra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

4. The method of any one of claims 1-3, wherein the method comprises receiving (1105) a request for the message reporting capabilities and sending the message reporting capabilities in response to the request

5. The method of claim 4, wherein the request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR-DC, for one or more band combinations supported by the UE.

6. The method of claim 5, wherein the method comprises, in response to the request, including only asynchronous FR1-FR2 NR-DC support for a band combination and omitting any mtra-FR NR-DC support for the band combination.

7. The method of any one of claims 1-6, wherein the method further comprises: receiving (1160), from a network node, configuration information configuring the UE for dual connectivity in accordance with the capabilities reported in the message.

8. A method performed by a base station of a wireless network, for handling capability information for a user equipment, UE, the method comprising: receiving (1210), in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both; and receiving (1220), in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

9. The method of claim 8, wherein FR1-FR2 NR-DC is dual connectivity, DC, with a master cell group, MCG, and a secondary cell group, SCG, that both employ NR radio access technology and where the MCG uses only frequency bands below 6 GHz and the SCG uses only frequency bands between 24.25 GHz and 52.6 GHz.

10. The method of claim 8 or 9, further comprising: receiving (1250), in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous mtra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

11. The method of any one of claims 8-10, wherein the method comprises sending (1205) a request for the message reporting capabilities and receiving the message reporting capabilities in response to the request

12. The method of claim 11, wherein the request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR-DC, for one or more band combinations supported by the UE.

13. The method of claim 12, wherein the message is received in response to the request and includes only asynchronous FR1-FR2 NR-DC support for a band combination and omits any intra-FR NR-DC support for the band combination.

14. The method of any of claims 8-13, further comprising configuring (1260) the UE for dual connectivity operation, based on the message.

15. A user equipment (50), comprising: transceiver circuitry (56); and processing circuitry (52) operatively associated with the transceiver circuitry (56) and configured to: indicate, in a message reporting capabilities for the UE, whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both, wherein included in the message reporting capabilities for the UE is a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

16. The user equipment (50) of claim 15, wherein FR1-FR2 NR-DC is dual connectivity, DC, with a master cell group, MCG, and a secondary cell group, SCG, that both employ NR radio access technology and where the MCG uses only frequency bands below 6 GHz and the SCG uses only frequency bands between 24.25 GHz and 52.6 GHz.

17. The user equipment (50) of claim 15 or 16, wherein the processing circuitry (56) is further configured to: include, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous mtra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

18. The user equipment (50) of any one of claims 15-17, wherein the processing circuitry (56) is configured to receive a request for the message reporting capabilities and send the message reporting capabilities in response to the request

19. The user equipment (50) of claim 18, wherein the request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR-DC, for one or more band combinations supported by the UE.

20. The user equipment (50) of claim 19, wherein the processing circuitry (56) is configured to, in response to the request include only asynchronous FR1-FR2 NR-DC support for a band combination and omitting any mtra-FR NR-DC support for the band combination.

21. The user equipment (50) of any one of claims 15-20, wherein the processing circuitry (56) is configured to receive, from a network node, configuration information configuring the UE for dual connectivity in accordance with the capabilities reported in the message.

22. A network node (30) comprising: transceiver circuitry (36); and processing circuitry (32) operatively associated with the transceiver circuitry (36) and configured to: receive, in a message reporting capabilities for the UE, information indicating whether each band in a band combination supported by the UE can be used in a master cell group, MCG, a secondary cell group, SCG, or both; and receive, in the message reporting capabilities for the UE, a bit for each of one or more band combinations supported by the UE, the bit indicating whether asynchronous FR1-FR2 NR-DC is supported by the UE for the corresponding band combination.

23. The network node (30) of claim 22, wherein FR1-FR2 NR-DC is dual connectivity, DC, with a master cell group, MCG, and a secondary cell group, SCG, that both employ NR radio access technology and where the MCG uses only frequency bands below 6 GHz and the SCG uses only frequency bands between 24.25 GHz and 52.6 GHz.

24. The network node (30) of claim 22 or 23, wherein the processing circuitry (36) is further configured to: receive, in the message reporting capabilities for the UE, cell grouping information indicating which bands in a band combination supported by the UE can be grouped in a first cell group for asynchronous mtra-FR NR-DC and which bands in the band combination can be grouped in a second cell group for asynchronous intra-FR NR-DC.

25. The network node (30) of any one of claims 22-24, wherein the processing circuitry (36) is configured to send a request for the message reporting capabilities and receive the message reporting capabilities in response to the request.

26. The network node (30) of claim 25, wherein the request comprises a field indicating that the message should indicate UE capabilities for FR1-FR2 NR-DC, for one or more band combinations supported by the UE.

27. The network node (30) of claim 26, wherein the processing circuitry (36) is configured to receive the message in response to the request and wherein the message includes only asynchronous FR1-FR2 NR-DC support for a band combination and omits any mtra-FR NR-DC support for the band combination.

28. The network node (30) of any of claims 22-27, wherein the processing circuitry (36) is configured to configure the UE for dual connectivity operation, based on the message.

29. A user equipment (50) adapted to perform a method according to any one of claims 1-7.

30. A base station adapted to perform a method according to any one of claims 8-14.

31. A computer program product comprising computer program instructions configured so that, when executed on at least one processing circuit of a user equipment, the computer program instructions cause the user equipment to carry out a method according to any one of claims 1-7.

32. A computer-readable medium comprising, stored thereupon, the computer program product of claim 31.

33. A computer program product comprising computer program instructions configured so that, when executed on at least one processing circuit of a network node or base station, cause the network node or base station to carry out a method according to any one of claims 8-14.

34. A computer-readable medium comprising, stored thereupon, the computer program product of claim 33.