WO2023197228A1

WO2023197228A1 - Mechanism for controlling user equipment capability in multi node network

Info

Publication number: WO2023197228A1
Application number: PCT/CN2022/086722
Authority: WO
Inventors: Janne Veikko Kaasalainen; Jian Qin ZHENG; Rossella De BENEDITTIS; Jacek DRABEK; Jakub CZAK
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2022-04-13
Filing date: 2022-04-13
Publication date: 2023-10-19

Abstract

Embodiments of the present disclosure relate to controlling user equipment (UE) capability in a multi node network. According to embodiments of the present disclosure, if a first network device determines that a terminal device is to be configured with a dual connectivity with the first network device and a second network device, the first network device transmits a node addition request to the second network device. The node addition request comprises a first set of mandatory UE capability parameters for the first device and a second set of optional UE capability parameter for the first device. The second network device transmits a node addition request to the first network device. In this way, the UE capability information can be coordinated between network devices, thereby allowing efficient usage of the UE capability and maximizing the UE throughput.

Description

MECHANISM FOR CONTROLLING USER EQUIPMENT CAPABILITY IN MULTI NODE NETWORK

FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for controlling user equipment (UE) capability in a multi node network.

BACKGROUND

With development of communication technologies, it requires larger communication capacity. In some scenarios, a terminal device can be configured with a plurality of cells. One important aspect of the new radio (NR) communication system is that the NR communication system supports carrier aggregation and dual connectivity. Carrier aggregation (CA) and dual connectivity are a very efficient way to increase downlink capacity such that when needed the system can assign additional downlink resources to the User Equipment (UE) by aggregating resources from multiple downlink carriers. CA is a technique used in wireless communication to increase a data rate per user or extend the coverage, where multiple component carriers are configured to a same user. In Carrier Aggregation (CA) , two or more Component Carriers (CCs) are aggregated. A UE may simultaneously receive or transmit on one or multiple CCs depending on its capabilities. A component carrier is referred to as a serving cell and it is treated as such by higher layers.

SUMMARY

Generally, embodiments of the present disclosure relate to a method for a detecting cell in scenarios of carrier aggregation and dual connectivity.

In a first aspect, there is provided a first device. The first device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the first device to: determine that a terminal device is to be configured with a dual connectivity with the first network device and a second network device; transmit to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and receive from the second network device a node addition response for the node addition request.

In a second aspect, there is provided a second device. The second device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the second device to receive from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and transmit to the first network device a node addition response for the node addition request.

In a third aspect, there is provided a method. The method comprises determining that a terminal device is to be configured with a dual connectivity with the first network device and a second network device; transmitting to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and receiving from the second network device a node addition response for the node addition request.

In a fourth aspect, there is provided a method. The method comprises receiving from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and transmitting to the first network device a node addition response for the node addition request.

In a fifth aspect, there is provided an apparatus. The apparatus comprise means for determining that a terminal device is to be configured with a dual connectivity with the first network device and a second network device; means for transmitting to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and means for receiving from the second network device a node addition response for the node addition request.

In a sixth aspect, there is provided an apparatus. The apparatus comprises means for receiving from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and means for transmitting to the first network device a node addition response for the node addition request.

In a seventh aspect, there is provided a computer readable medium. The computer readable medium comprises program instructions for causing an apparatus to perform at least the method according to any one of the above fourth, fifth, or sixth aspects.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:

Fig. 1 illustrates an example communication environment according to conventional technologies;

Fig. 2 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

Fig. 3 illustrates a signaling flow for coordinating UE capabilities between two network devices according to some example embodiments of the present disclosure;

Fig. 4 illustrates a signaling flow for delivering adjustment factors according to other example embodiments of the present disclosure;

Fig. 5 illustrates a flowchart of a method implemented at a first apparatus according to some example embodiments of the present disclosure;

Fig. 6 illustrates a flowchart of a method implemented at a second apparatus according to some other example embodiments of the present disclosure;

Fig. 7 illustrates a simplified block diagram of an apparatus that is suitable for implementing example embodiments of the present disclosure; and

Fig. 8 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.65G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, an Integrated and Access Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. The term “terminal device” refers to any end device that may be capable of wireless communication. In the following description, the terms “terminal device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

As described above, the carrier aggregation is an important feature for the NR communication system. In the scenario of carrier aggregation, the terminal device usually connects with a primary cell and one or more secondary cell. The terminal device usually supports receiving beam forming. Besides, there are two different frequency ranges, i.e., FR1 and FR2. The FR1 usually refers to the frequency below 6GHz and the FR2 refers to the frequency above 6GHz. The terminal device may behave differently in different frequency ranges. There are two main types of carrier aggregations, Carrier Aggregation (CA) and Dual-Connectivity (DC) . CA implies that there is one cell group only serving the UE composed of one special Cell (PCell) and one or more Secondary Cells (SCell) . DC implies two cell groups, Master Cell Group (MCG) and Secondary Cell Group (SCG) respectively, each with one special cell and none or one or more than one SCell.

According to conventional technologies, a terminal device may need to inform its capabilities. For example, UE Capability Information may be an RRC message that UE sent to Network (in most case during initial registration process) . It informs on all the details of its capabilities. It specifies UE capabilities on structured way. The capabilities can be on band level, band combination level, feature set level or feature set per carrier component (CC) level. The way allows for the UE very flexible way to map needed capabilities for each possible configuration. The flexible UE capability signaling is in some cases challenging from network point of view and the current definitions may lead to suboptimal result.

Fig. 1 shows an example where a UE 10 is having a radio resource control (RRC) connection in gNB1 and in cell1. When the UE 10 needs more throughput the gNB1 may configure either carrier aggregation for cell2 or trigger NR-DC over Xn interface for cell3 with gNB-2. One problem here is that cell2 may be in FR1 but due to lower bandwidth (BW) it provides lower capacity than wideband cell3 with FR2. UE 10 may be in the location where it actually cannot immediately report good enough measurement result for cell3 and hence report only cell2. gNB knows that the in the cell1 coverage area there is a good possibility to use FR2. Not to cause any delay for the UE 10 throughput demand, the gNB1 CU1 configures CA with Cell1 and Cell2, still keeping the possibility to aggregate also Cell3 when reported by the UE. The gNb1-CU in this case can limit the configuration in gNB-2 providing allowed band combinations (BC) that do not violate the UE capability and are compatible with the CA configuration used by gNB-1-DU.

However, the problem with the allowed BC limitation is that it only limits the options in the band combination list. In addition to the band combinations, some UE capability parameters are actually common for all bands in the band combination. These parameters have a relation to how many carriers for the UE can be configured or how many concurrent quality reports (CSI reports) the UE can handle optimally. Exceed of UE capability may cause immediate RRC configuration failure or in some cases, when the number of requested concurrent CSI reports exceeds the UE capability, performance degradation as in this case the network does not know which CC quality report the UE will skip.

So even if the gNB2 would limit the band combinations it does not have any control how many CSI reports the first node (gNB1-DU1) would configure. If the gNB-DU1 configures too many CSI reports it may prevent usage in other nodes (like gNB2) as the previous node have used all or too much UE capability.

Number of needed CSI reports depends on the configuration and how much the gNb-DU wants to optimize the UE performance. More CSI-RS reports may provide better performance but it may not be always needed, as the UE capacity can be also increased with a smaller number of CSI reports.

Convention technology does not specify how different nodes should coordinate the usage of shared UE capability nor how this sharing can be done. According to some legacy technologies, although some UE capabilities require coordination between the Master Node (MN) and the Secondary Node (SN) in case of NR-DC, no inter-node signaling has been defined so far to support such coordination.

Without inter-node coordination, in order to avoid a call drop or performance degradation, in case a gNB (gNB1) wants to configure Cells (e.g. via NR-DC) belonging to another gNB (gNB2) it may first try to downgrade UE configuration by e.g. removing CA but in worst case scenario even this may not help as gNB1-DU may still optimize functionality for single carrier and configure too many CSI-RS signals for the UE so that nothing or too few is left to gNB2. The priority for CSI reporting has been defined. It defines rules how the UE prioritizes different CSI reports in case its processing capacity usage (CPU) is exceeded. However, these rules do not completely solve the problem. gNb may not be operate properly if some report is continuously reported.

In order to solve at least part of the above and other potential, solutions on coordinating UE capabilities between network nodes are proposed. According to embodiments of the present disclosure, if a first network device determines that a terminal device is to be configured with cells from different devices, e.g. with a dual connectivity with the first network device and a second network device, the first network device transmits a node addition request to the second network device. The node addition request comprises a first set of mandatory UE capability parameters which are reserved for the first device and a second set of optional UE capability parameters for the first device that can be used by the second device. The second network device transmits a node addition response to the first network device indicating which shareable UE capability parameters would like to take. In this way, the UE capability information can be coordinated between network devices, thereby allowing efficient usage of the UE capability and maximizing the UE throughput.

Fig. 2 illustrates a schematic diagram of a communication environment 100 in which embodiments of the present disclosure can be implemented. The communication environment 100 comprises a network device 110-1 and a network device 110-2. The network device (i.e., the network device 110-1 and the network device 110-2) can be divided into two physical entities named centralized unit (CU) and distributed unit (DU) . CU provides support for the higher layers of the protocol stack such as service data adaptation protocol (SDAP) , packet data convergence protocol (PDCP) and RRC while DU provides support for the lower layers of the protocol stack such as radio link control (RLC) , medium access control (MAC) and Physical layer. As shown in Fig. 2, the network device 110-1 comprises a CU 1101 and a DU 1102. The network device 110-2 comprises a CU 1201 and a DU 1202. It should be noted that the number of network devices shown in Fig. 2 is only an example not limitation. The communication environment 100 can comprise any proper number of network devices. The communication environment 100, which is a part of a communication network, further comprises a terminal device 120-1, a terminal device 120-2, ...., a terminal device 120-N, which can be collectively referred to as “terminal device (s) 120. ”

The communication environment 100 may comprise any suitable number of devices and cells. In the communication environment 100, the network device 110 and the terminal device 120 can communicate data and control information to each other. The network devices 110-1 and 110-2 can also communicate with each other. The terminal device 120 can be configured with more than one cell.

Communications in the communication environment 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA) , Frequency Division Multiple Access (FDMA) , Time Division Multiple Access (TDMA) , Frequency Division Duplex (FDD) , Time Division Duplex (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiple (OFDM) , Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and/or any other technologies currently known or to be developed in the future.

Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Reference is now made to Fig. 3, which illustrates a signaling flow 200 for coordinating UE capabilities according to example embodiments of the present disclosure. For the purpose of discussion, the signaling flow 200 will be described with reference to Fig. 2. Only for the purpose of illustrations, the signaling flow 200 may involve the network device 110-1, the network device 110-2 and the terminal device 120-1.

In some example embodiments, the network device 110-1 may transmit 2005 configuration information which may indicate a measurement configuration to the terminal device 120-1. For example, the measurement configuration can comprise one or more of: a reference signal (RS) type, a measurement periodicity, a measurement RS transmission period specific. The measurement configuration can also indicate where to measure the set of reference signals in time domain. Alternatively or in addition, the measurement configuration can also indicate where to measure the set of reference signals in frequency domain. The network device 110-1 may configure the terminal device 120-1 to measure at least one of: CA neighbor cells or NR-DC neighbor cells.

The terminal device 120-1 may perform a measurement on a set of reference signals. In some example embodiments, the terminal device 120-1 can measure reference signal received power (RSRP) on the set of reference signals. In other embodiments, the terminal device 120-1 can measure reference signal received quality (RSRQ) on the set of reference signals. Alternatively or in addition, the terminal device 120-1 can obtain received signal strength indicator (RSSI) of the set of reference signals. Based on these measurements and alternatively other measurements, the terminal device 120-1 may obtain the information needed for the measurement report. The terminal device 120-1 may transmit 2010 the measurement report to the network device 110-1. In some embodiments, the measurement report may be for CA neighbor cells and/or NR-DC neighbor cells.

The network device 110-1 (for example, the CU 1101) may determine 2015 to configure CA for the terminal device 110-1. Alternatively, the network device 110-1 (for example, the CU 1101) may determine 2015 to configure or trigger DC for the terminal device 110-1. By way of example, in some embodiments, if the data buffer for the terminal device 110-1 indicates that the terminal device 110-1 needs more throughput, the network device 110-1 may configure either CA or trigger DC for the terminal device 110-1. For example, the network device 110-1 may configure CA and may indicate with a new information element (IE) that the terminal device 120-1 may be later configured also with NR-DC or more resources. In this case, the network device 110-1 may optimize the UE capability usage by dividing it into two parts. The actually UE RRC configuration may be configured with all needed resources, but for the network device 110-1, the UE capability may be divided into two parts, i.e., mandatory and optional parameters.

In some example embodiments, the CU 110-1 may transmit 2020 a first request to the DU 1102. The first request may comprise a first information element which indicates that the terminal device 110-1 is to be configured with the dual connectivity. In some embodiments, the first request may be a UE context modification request. Alternatively, the first request may be a UE context setup request.

In addition, the DU 1102 may transmit 2025 a first response for the first request to the CU 1101. The first response may comprise the first set of mandatory UE capability parameters for the network device 110-1. For example, the DU 1102 may configure a set of carriers for the terminal device 120-1. The set of carriers may need resources and usage of the resources may need capability. For example, the resources may be channel state information reference signal (CSI-RS) reports. It should be noted that the resources may be any proper types of resources for the carriers. In this case, the mandatory UE capability parameters may be associated with the set of carriers configured by the DU 1102 for the terminal device 120-1. The mandatory UE capability parameters may comprise a maximum number of simultaneous CSI reference signals. For example, the mandatory UE capability parameters may comprise the parameter “maxNumberSimultaneousNZP-CSI-RS-ActBWP-AllCC. ” Alternatively or in addition, the mandatory UE capability parameters may comprise a total number of ports of CSI reference signal. For example, the mandatory UE capability parameters may comprise the parameter “totalNumberPortsSimultaneousNZP-CSI-RS-ActBWP-AllCC. ” In some embodiments, the mandatory UE capability parameters may comprise simultaneous CSI reports. For example, the mandatory UE capability parameters may comprise the parameter “simultaneousCSI-ReportsAllCC. ” Alternatively or in addition, the mandatory UE capability parameters may comprise a maximum number of synchronization signal/broadcast blocks (SSBs) . For example, the mandatory UE capability parameters may comprise the parameter “maxNumberSSB-BFD. ” The mandatory UE capability parameters may also comprise a parameter that is common for the network devices 110-1 and 110-2.

The first response may also comprise the second set of optional UE capability parameter for the network device 110-1. In some example embodiments, the CU 1101 may store 2030 the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1.

In some example embodiments, the network device 110-1 may perform 2035 a RRC configuration procedure with the terminal device 120-1. For example, the CU 1101 may transmit a RRC reconfiguration for the terminal device 120-1 via the DU 1102. The terminal device 120-1 may transmit a RRC reconfiguration complete message to the CU 1101 via the DU 1102.

The network device 110-1 (for example, the CU 1101) determines 2040 that the terminal device 120-1 is to be configured the dual connectivity with the network device 110-1 and the network device 110-2. For example, in some embodiments, the terminal device 120-1 may transmit a measurement result to the CU 1101. This measurement result may indicate NR-DC possibility. In this case, the CU 1101 may identify that the terminal device 120-1 can be configured with DC on top of previous CA configuration.

The network device 110-1 (for example, the CU 1101) transmits 2045 a node addition request to the network device 110-2 (for example, the CU1201) . The node addition request indicates the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1. For example, the node addition request may comprise IEs which comprise the first set of mandatory UE capability parameters and the second set of optional UE capability parameter. In some embodiments, the IEs may be added to the configured grant (CG) configuration information inter-node message exchanged between the network device 110-1 and the network device 110-2 over Xn interface.

The node addition request may indicate a UE capability budget for the network device 110-2. For example, in some example embodiments, the network device 110-1 may share the needed UE capabilities for the DUs and the neighbor network device (for example, the network device 110-2) . In this case, the network device 110-1 may divide the UE capabilities to share and the node addition request may indicate the maximum allowed amount of the UE capabilities. Alternatively, the network device 110-1 may use resources from a limited UE capability to be shared among all network devices serving the terminal device 120-1. In this case, the node addition request may indicate the minimum number of resources from that limited UE capability that the network device 110-2 can safely use. Remaining resources may be considered as optional, i.e., not needed to be used.

In some other embodiments, the network device 110-1 may inform the terminal device 120-1 about a priority order of the allocated resources. For example, the network device 110-1 may identify risk of exceeding UE CSI reporting capability and may define detailed rules how needed reports can be reported so that the terminal device 120-1 may not always drop same lowest priority CSI measurement result. For example, the priority of CSI reports may be modified so that lower priority reports priority can increase gradually. This allows the network device to receive also those reports that otherwise would be always dropped due to higher priority reports.

In some embodiments, when the network device 110-2 receives the request to configure more carriers and uses resources from the same UE capability, the network device 110-2 may know how many resources are still available from the respective UE capability and what is really the minimum set that the network device 110-1 needs. In this case, if the network device 110-2 identifies that the network device 110-1 has used more resources than it needs, the network device 110-2 can check if some of those are marked as optional. In the case, the network device 110-2 may trigger configuration downgrade for the first node. In this way, the network device 110-2 can configure needed resources from the UE capability, which allows efficient usage of the UE capability and maximizing the UE throughput.

The CU 1201 may transmit 2050 a UE context setup request to the DU 1202. The UE context setup request may comprise the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1.

The DU 1202 may transmit 2055 a UE context setup response to the CU 1201. In some embodiments, as mentioned above, the node addition request may indicate the minimum number of resources from that limited UE capability that the network device 110-2 can safely use. If the DU 1201 identifies that it needs bigger share from the UE capability than the safely used UE capability, the CU 120-1 may check whether there may be UE capability defined as optional for the network device 110-1. In this case, if such resources exceed UE capability, the UE context setup response may comprise an indication regarding which resource to be downgraded for the network device 110-1. In some embodiments, the indication may be added to CG configuration inter-node message, which is delivered from DU 1202 to CU1201 over the F1 interface, then from CU1201 to CU 1101 over Xn interface and eventually from CU1101 to DU 1102 over the F1 interface.

The network device 110-2 (for example, the CU 1201) transmits 2060 a node addition response to the network device 110-1 (for example, the CU 1101) . As mentioned above, the UE context setup response may comprise an indication regarding which resource to be downgraded for the network device 110-1. In this case, the node addition response may also comprise the indication about which resources need downgrade.

In some embodiments, the node addition response may indicate that UE capability budget is accepted by the network device 110-2. Alternatively, the node addition response may indicate a negotiation for the UE capability budget for the network device 110-2. In this case, there may one or more rounds of negotiations. For example, the node addition response may indicate the amount of UE capability required by the network device 110-2. The network device 110-1 may determine whether the amount of UE capability required by the network device 110-2 are acceptable. If it is not acceptable, the network device 110-1 may inform the network device 110-2 that the amount of UE capability required by the network device 110-2 are not acceptable. In this case, the network device 110-1 may also inform the network device 110-2 about another amount of UE capability which can be provided to the network device 110-2.

In some example embodiments, the CU 1101 may transmit 2065 a second request to the DU 1102. For example, the second request may be a UE context modification request. The second request may comprise a second information element which comprises the indication regarding which resource to be downgraded for the network 110-1.

The DU 1102 may transmit 2070 a second response to the CU 1101. For example, the second request may be a UE context modification response. The DU 1102 may update UE capability parameters based on the indication in the second request. For example, the DU 1102 may remove, from the UE configuration, the needed count of resources. In this case, the second response may comprise a third set of mandatory UE capability parameters for the network device 110-1 and a fourth set of optional UE capability parameter for the network device 110-1.

It should be noted that embodiments with reference to Fig. 3 is an example about configuration order of different network devices. Alternatively, the terminal device 120-1 can be configured first dual connectivity and after that carrier aggregation. Configuration of carrier aggregation and dual connectivity are separate procedures.

In some embodiments, the CU 1101 may configure the terminal device 120-1 with the new configuration. For example, referring to Fig. 4, the CU 1101 may transmit 3010 a third request to the DU 1102. The third request may be a UE context modification request. In some embodiments, the network device 110-1 may add resources for the UE configuration. The network device 110-1 may configure more CSI reports to the terminal device 120-1. In this case, the third request may be transmitted.

The DU 1102 may determine 3020 that CSI report capability is to be exceeded. In this case, the DU 1102 can fill a new IE to indicates that the CSI report capability is to be exceeded and deliver the new IE to the CU 1101. For example, the network device 110-1 may identify risk of exceeding UE CSI reporting capability and may define detailed rules how all needed reports can be reported. For example, the priority of CSI reports may be modified so that lower priority reports priority can increase gradually. This allows the gNB to receive also those reports that otherwise would be always dropped due to higher priority reports. The DU 1102 may transmit 3030 a third response to the CU 1101. The third response may be a UE context modification response. The third response may comprise the weight adjust factor for CSI reporting. In this way, this allows the network device to receive also those reports that otherwise would be always dropped due to higher priority reports.

Only as an example, the new CSI reporting weight factor may be used to modify CSI report priority formula (ref. for example, the CSI report priority formula defined in TS 38.214 section 5.2.5) to allow UE to report lower priority reports: Pri _iCSI (y, k, c, s) =2·N _cells·M _s·y+N _cells·M _s·k+M _s·c+s + weightAdjustFactor *ignoreTimes, ignoreTimes is a new variable for the UE and means the times of the UE CPU of the CSI report is not started for the CSI report, reset every time the CPU is started, and weightAdjustFactor is a new RRC parameter and is indicated from gNB by RRC message. When the weightAdjustFactor equals to 0, it means no dynamic adjustment. When weightAdjustFactor is bigger than 0, it means the priority is dynamically increased so as the low priority report can get updated when it’s been stopped update for a long time. In some embodiments, the weightAdjustFactor may be configured per port, which achieves usage flexibility. It should be noted the CSI reporting priority formula is only an example not limitation.

The CU 1101 may transmit 3040 a configuration to the terminal device 120-1. The configuration may comprise a third information element which comprises the weight adjust factor for CSI reporting. The terminal device 120-1 may transmit 3050 a configuration complete message to the CU 1101. Table 1 below shows an example of the configuration. It should be noted the Table 1 is only an example not limitation.

Table 1

According to embodiments of the present disclosure, it is clear how different network nodes can share and control the UE capability in a controlled way. Embodiments of the present disclosure solves problems for UE capabilities related to all CCs that the same UE capability needs to be used and shared by multiple network nodes. Embodiments of the present disclosure are useful for example when the UE capability is limited due to limited number of simultaneous CSI-RS measurement processing it can support.

Fig. 5 shows a flowchart of an example method 400 in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 400 will be described from the perspective of the network device. Only for the purpose of illustrations, the method 400 is described with the reference to the network device 110-1.

In some example embodiments, the network device 110-1 may transmit configuration information which may indicate a measurement configuration to the terminal device 120-1. For example, the measurement configuration can comprise one or more of: a reference signal (RS) type, a measurement periodicity, a measurement RS transmission period specific. The measurement configuration can also indicate where to measure the set of reference signals in time domain. Alternatively or in addition, the measurement configuration can also indicate where to measure the set of reference signals in frequency domain. The network device 110-1 may configure the terminal device 120-1 to measure at least one of: CA neighbor cells or NR-DC neighbor cells.

The network device 110-1 may receive a measurement report from the terminal device 120-1. In some embodiments, the measurement report may be for CA neighbor cells and/or NR-DC neighbor cells.

The network device 110-1 (for example, the CU 1101) may determine to configure CA for the terminal device 110-1. Alternatively, the network device 110-1 (for example, the CU 1101) may determine to configure or trigger DC for the terminal device 110-1. By way of example, in some embodiments, if the data buffer for the terminal device 110-1 indicates that the terminal device 110-1 needs more throughput, the network device 110-1 may configure either CA or trigger DC for the terminal device 110-1. For example, the network device 110-1 may configure CA and may indicate with a new information element (IE) that the terminal device 120-1 may be later configured also with NR-DC or more resources. In this case, the network device 110-1 may optimize the UE capability usage by dividing it into two parts. The actually UE RRC configuration may be configured with all needed resources, but for the network device 110-1, the UE capability may be divided into two parts, i.e., mandatory and optional parameters.

In some example embodiments, the CU 110-1 may transmit a first request to the DU 1102. The first request may comprise a first information element which indicates that the terminal device 110-1 is to be configured with the dual connectivity. In some embodiments, the first request may be a UE context modification request. Alternatively, the first request may be a UE context setup request.

In addition, the DU 1102 may transmit a first response for the first request to the CU 1101. The first response may comprise the first set of mandatory UE capability parameters for the network device 110-1. For example, the DU 1102 may configure a set of carriers for the terminal device 120-1. The set of carriers may need resources and usage of the resources may need capability. For example, the resources may be channel state information reference signal (CSI-RS) reports. It should be noted that the resources may be any proper types of resources for the carriers. In this case, the mandatory UE capability parameters may be associated with the set of carriers configured by the DU 1102 for the terminal device 120-1. The mandatory UE capability parameters may comprise a maximum number of simultaneous CSI reference signals. For example, the mandatory UE capability parameters may comprise the parameter “maxNumberSimultaneousNZP-CSI-RS-ActBWP-AllCC. ” Alternatively or in addition, the mandatory UE capability parameters may comprise a total number ports of CSI reference signal. For example, the mandatory UE capability parameters may comprise the parameter “totalNumberPortsSimultaneousNZP-CSI-RS-ActBWP-AllCC. ” In some embodiments, the mandatory UE capability parameters may comprise simultaneous CSI reports. For example, th mandatory UE capability parameters may comprise the parameter “simultaneousCSI-ReportsAllCC. ” Alternatively or in addition, the mandatory UE capability parameters may comprise a maximum number of synchronization signal/broadcast blocks (SSBs) . For example, the mandatory UE capability parameters may comprise the parameter “maxNumberSSB-BFD. ” The mandatory UE capability parameters may also comprise a parameter that is common for the network devices 110-1 and 110-2.

The first response may also comprise the second set of optional UE capability parameter for the network device 110-1. In some example embodiments, the CU 1101 may store the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1.

In some example embodiments, the network device 110-1 may perform a RRC configuration procedure with the terminal device 120-1. For example, the CU 1101 may transmit a RRC reconfiguration for the terminal device 120-1 via the DU 1102. The terminal device 120-1 may transmit a RRC reconfiguration complete message to the CU 1101 via the DU 1102.

At block 410, the network device 110-1 (for example, the CU 1101) determines that the terminal device 120-1 is to be configured the dual connectivity with the network device 110-1 and the network device 110-2. For example, in some embodiments, the terminal device 120-1 may transmit a measurement result to the CU 1101. This measurement result may indicate NR-DC possibility. In this case, the CU 1101 may identify that the terminal device 120-1 can be configured with DC on top of previous CA configuration.

At block 420, the network device 110-1 (for example, the CU 1101) transmits a node addition request to the network device 110-2 (for example, the CU1201) . The node addition request indicates the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1. For example, the node addition request may comprise IEs which comprise the first set of mandatory UE capability parameters and the second set of optional UE capability parameter. In some embodiments, the IEs may be added to the configured grant (CG) configuration information inter-node message exchanged between the network device 110-1 and the network device 110-2 over Xn interface.

At block 430, the network device 110-1 (for example, the CU 1101) receives a node addition response from the network device 110-2 (for example, the CU 1201) . As mentioned above, the UE context setup response may comprise an indication regarding which resource to be downgraded for the network device 110-1. In this case, the node addition response may also comprise the indication about which resources need downgrade.

In some example embodiments, the CU 1101 may transmit a second request to the DU 1102. For example, the second request may be a UE context modification request. The second request may comprise a second information element which comprises the indication regarding which resource to be downgraded for the network 110-1.

The DU 1102 may transmit a second response to the CU 1101. For example, the second request may be a UE context modification response. The DU 1102 may update UE capability parameters based on the indication in the second request. For example, the DU 1102 may remove, from the UE configuration, the needed count of resources. In this case, the second response may comprise a third set of mandatory UE capability parameters for the network device 110-1 and a fourth set of optional UE capability parameter for the network device 110-1.

In some embodiments, the CU 1101 may configure the terminal device 120-1 with the new configuration. For example, the CU 1101 may transmit a third request to the DU 1102. The third request may be a UE context modification request. In some embodiments, the network device 110-1 may add resources for the UE configuration. The network device 110-1 may configure more CSI reports to the terminal device 120-1. In this case, the third request may be transmitted.

The CU 1101 may determine that CSI report capability is to be exceeded. For example, the network device 110-1 may identify risk of exceeding UE CSI reporting capability and may define detailed rules how all needed reports can be reported. For example, the priority of CSI reports may be modified so that lower priority reports priority can increase gradually. This allows the gNB to receive also those reports that otherwise would be always dropped due to higher priority reports. The DU 1102 may transmit 3030 a third response to the CU 1101. The third response may be a UE context modification response. The third response may comprise the weight adjust factor for CSI reporting. In this way, this allows the network device to receive also those reports that otherwise would be always dropped due to higher priority reports.

The DU 1102 may transmit a third response to the CU 1101. The third response may be a UE context modification response. The third response may comprise the weight adjust factor for CSI reporting. The new CSI reporting weight factor may be used to modify a conventional CSI reporting priority formula (ref. for example, the CSI report priority formula defined in TS 38.214 section 5.2.5) to allow UE to report lower priority reports: Pri _iCSI (y, k, c, s) =2·N _cells·M _s·y+N _cells·M _s·k+M _s·c+s +weightAdjustFactor *ignoreTimes, ignoreTimes is a new variable for the UE and means the times of the UE CPU of the CSI report is not started for the CSI report, reset every time the CPU is started, and weightAdjustFactor is a new RRC parameter and is indicated from gNB by RRC message. When the weightAdjustFactor equals to 0, it means no dynamic adjustment. When weightAdjustFactor is bigger than 0, it means the priority is dynamically increased so as the low priority report can get updated when it’s been stopped update for a long time. In some embodiments, the weightAdjustFactor may be configured per port, which achieves usage flexibility. It should be noted the CSI reporting priority formula is only an example not limitation.

The CU 1101 may transmit a configuration to the terminal device 120-1. The configuration may comprise a third information element which comprises the weight adjust factor for CSI reporting. The terminal device 120-1 may transmit 3050 a configuration complete message to the CU 1101.

Fig. 6 shows a flowchart of an example method 500 in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 500 will be described from the perspective of the network device. Only for the purpose of illustrations, the method 500 is described with the reference to the network device 110-2.

At block 510, the network device 110-2 (for example, the CU 1201) receives a node addition request from the network device 110-1 (for example, the CU1101) . The node addition request indicates the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1. For example, the node addition request may comprise IEs which comprise the first set of mandatory UE capability parameters and the second set of optional UE capability parameter. In some embodiments, the IEs may be added to the configured grant (CG) configuration information inter-node message exchanged between the network device 110-1 and the network device 110-2 over Xn interface.

In some embodiments, the CU 1201 may transmit a UE context setup request to the DU 1202. The UE context setup request may comprise the first set of mandatory UE capability parameters for the network device 110-1 and the second set of optional UE capability parameter for the network device 110-1.

The DU 1202 may transmit a UE context setup response to the CU 1201. In some embodiments, as mentioned above, the node addition request may indicate the minimum number of resources from that limited UE capability that the network device 110-2 can safely use. If the DU 1201 identifies that it needs bigger share from the UE capability than the safely used UE capability, the CU 120-1 may check whether there may be UE capability defined as optional for the network device 110-1. In this case, if such resources exceed UE capability, the UE context setup response may comprise an indication regarding which resource to be downgraded for the network device 110-1. In some embodiments, the indication may be added to CG configuration inter-node message, which is delivered from DU 1202 to CU1201 over the F1 interface, then from CU1201 to CU 1101 over Xn interface and eventually from CU1101 to DU 1102 over the F1 interface.

At block 520, the network device 110-2 (for example, the CU 1201) transmits a node addition response to the network device 110-1 (for example, the CU 1101) . As mentioned above, the UE context setup response may comprise an indication regarding which resource to be downgraded for the network device 110-1. In this case, the node addition response may also comprise the indication about which resources need downgrade.

In some example embodiments, an apparatus capable of performing any of the method 400 (for example, the network device 110-1) may comprise means for performing the respective operations of the method 400. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The apparatus may be implemented as or included in the network device 110-1. In some example embodiments, the means may comprise at least one processor and at least one memory including computer program code. The at least one memory and computer program code are configured to, with the at least one processor, cause performance of the apparatus.

In some example embodiments, the apparatus comprises means for determining, at a first network device, that a terminal device is to be configured with a dual connectivity with the first network device and a second network device; means for transmitting to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and means for receiving from the second network device a node addition response for the node addition request.

In some example embodiments, the apparatus comprises means for transmitting, at a first central unit (CU) of the first network device, a first request to a first distrusted unit (DU) of the first network device, the first request comprising a first information element which indicates that the terminal device is to be configured with the dual connectivity.

In some example embodiments, the apparatus comprises means for receiving, at the first CU, a first response from the first DU, the first response comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device, the first set of mandatory UE capability parameters being associated with a first set of carriers configured by the first DU for the terminal device.

In some example embodiments, the node addition response from the second network device comprises an indication regarding which resource to be downgraded for the first network device.

In some example embodiments, the apparatus comprises means for transmitting, at a first CU of the first network device, a second request to a first DU of the first network device, the second request comprising a second information element which comprises the indication regarding which resource to be downgraded for the first network device.

In some example embodiments, the apparatus comprises means for receiving, at the first CU, a second response from the first DU, the second response comprising a third set of mandatory UE capability parameters for the first network device and a fourth set of optional UE capability parameter for the first network device, and the third set of mandatory UE capability parameters and the fourth set of optional UE capability parameter being updated based on the indication.

In some example embodiments, the node addition request indicates a UE capability budget for the second network device.

In some example embodiments, the node addition response indicates that the UE capability budget is accepted by the second network device, or the node addition response indicates a negotiation for the UE capability budget for the second network device.

In some example embodiments, the apparatus comprises means for determining that a channel state information (CSI) reporting capability of the terminal device is to be exceeded; and means for transmitting to the terminal device a configuration comprising a third information element which comprises a weight adjust factor for CSI reporting.

In some example embodiments, the means for transmitting to the terminal device the configuration comprising the third information element comprises: means for receiving, at the first CU, a third response from the first DU, the third response comprising the weight adjust factor for CSI reporting; and means for transmitting, at the first CU and to the terminal device, the configuration comprising the third information element which comprises the weight adjust factor for CSI reporting.

In some example embodiments, the first set of mandatory UE capability parameters comprises at least one of: a maximum number of simultaneous CSI reference signals, a total number ports of CSI reference signal, simultaneous CSI reports, a maximum number of synchronization signal/broadcast blocks (SSBs) , or a parameter that is common for the first and second network devices.

In some example embodiments, an apparatus capable of performing any of the method 500 (for example, the network device 110-2) may comprise means for performing the respective operations of the method 500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The apparatus may be implemented as or included in the network device 110-2. In some example embodiments, the means may comprise at least one processor and at least one memory including computer program code. The at least one memory and computer program code are configured to, with the at least one processor, cause performance of the apparatus.

In some example embodiments, the apparatus comprises means for receiving, at a second network device and from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and means for transmitting to the first network device a node addition response for the node addition request.

In some example embodiments, the apparatus comprises means for transmitting, at a second central unit (CU) of the second network device, a UE context setup request to a second distrusted unit (DU) of the second network device, the UE context setup request comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device.

In some example embodiments, the apparatus comprises means for receiving, at the second CU, a UE context setup response from the second DU, the UE context setup response comprising an indication regarding which resource to be downgraded for the first network device.

Fig. 7 is a simplified block diagram of a device 600 that is suitable for implementing example embodiments of the present disclosure. The device 600 may be provided to implement a communication device, for example, the network device 110-1 or the network device 110-2 as shown in Fig. 2. As shown, the device 600 includes one or more processors 610, one or more memories 620 coupled to the processor 610, and one or more communication modules 640 coupled to the processor 610.

The communication module 640 is for bidirectional communications. The communication module 640 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 640 may include at least one antenna.

The processor 610 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 600 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The memory 620 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 624, an electrically programmable read only memory (EPROM) , a flash memory, a hard disk, a compact disc (CD) , a digital video disk (DVD) , an optical disk, a laser disk, and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 622 and other volatile memories that will not last in the power-down duration.

A computer program 630 includes computer executable instructions that are executed by the associated processor 610. The program 630 may be stored in the memory, e.g., ROM 624. The processor 610 may perform any suitable actions and processing by loading the program 630 into the RAM 622.

Example embodiments of the present disclosure may be implemented by means of the program 630 so that the device 600 may perform any process of the disclosure as discussed with reference to Figs. 3 to 6. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

In some example embodiments, the program 630 may be tangibly contained in a computer readable medium which may be included in the device 600 (such as in the memory 620) or other storage devices that are accessible by the device 600. The device 600 may load the program 630 from the computer readable medium to the RAM 622 for execution. The computer readable medium may include any types of tangible non-volatile storage, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and other magnetic storage and/or optical storage. Fig. 8 shows an example of the computer readable medium 700 in form of an optical storage disk. The computer readable medium has the program 630 stored thereon.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above with reference to Figs. 3 to 6. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A first network device comprising:

at least one processor; and

at least one memory including computer program codes;

the at least one memory and the computer program codes are configured to, with the at least one processor, cause the first network device to:

determine that a terminal device is to be configured with a dual connectivity with the first network device and a second network device;

transmit to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

receive from the second network device a node addition response for the node addition request.
The first network device of claim 1, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to:

transmit, at a first central unit (CU) of the first network device, a first request to a first distrusted unit (DU) of the first network device, the first request comprising a first information element which indicates that the terminal device is to be configured with the dual connectivity.
The first network device of claim 2, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to:

receive, at the first CU, a first response from the first DU, the first response comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device, the first set of mandatory UE capability parameters being associated with a first set of carriers configured by the first DU for the terminal device.
The first network device of any one of claims 1-3, wherein the node addition response from the second network device comprises an indication regarding which resource to be downgraded for the first network device.
The first network device of claim 4, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to:

transmit, at a first CU of the first network device, a second request to a first DU of the first network device, the second request comprising a second information element which comprises the indication regarding which resource to be downgraded for the first network device.
The first network device of claim 5, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to:

receive, at the first CU, a second response from the first DU, the second response comprising a third set of mandatory UE capability parameters for the first network device and a fourth set of optional UE capability parameter for the first network device, and the third set of mandatory UE capability parameters and the fourth set of optional UE capability parameter being updated based on the indication.
The first network device of any one of claims 1-6, wherein the node addition request indicates a UE capability budget for the second network device.
The first network device of claim 7, wherein the node addition response indicates that the UE capability budget is accepted by the second network device, or

wherein the node addition response indicates a negotiation for the UE capability budget for the second network device.
The first network device of any one of claims 1-8, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to:

determine that a channel state information (CSI) reporting capability of the terminal device is to be exceeded; and

transmit to the terminal device a configuration comprising a third information element which comprises a weight adjust factor for CSI reporting.
The first network device of any one of claims 1-8, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first network device to transmit to the terminal device the configuration comprising the third information element by:

receiving, at the first CU, a third response from the first DU, the third response comprising the weight adjust factor for CSI reporting; and

transmitting, at the first CU and to the terminal device, the configuration comprising the third information element which comprises the weight adjust factor for CSI reporting.
The first network device of any one of claims 1-8, wherein the first set of mandatory UE capability parameters comprises at least one of:

a maximum number of simultaneous CSI reference signals,

a total number ports of CSI reference signal,

simultaneous CSI reports,

a maximum number of synchronization signal/broadcast blocks (SSBs) , or

a parameter that is common for the first and second network devices.
A second network device comprising:

at least one processor; and

at least one memory including computer program codes;

the at least one memory and the computer program codes are configured to, with the at least one processor, cause the second network device to:

receive from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

transmit to the first network device a node addition response for the node addition request.
The second network device of claim 1, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the second network device to:

transmit, at a second central unit (CU) of the second network device, a UE context setup request to a second distrusted unit (DU) of the second network device, the UE context setup request comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device.
The second network device of claim 13, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the second network device to:

receive, at the second CU, a UE context setup response from the second DU, the UE context setup response comprising an indication regarding which resource to be downgraded for the first network device.
The second network device of any one of claims 12-14, wherein the node addition request indicates a UE capability budget for the second network device.
The second network device of claim 15, wherein the node addition response indicates that the UE capability budget is accepted by the second network device, or

wherein the node addition response indicates a negotiation for the UE capability budget for the second network device.
The second network device of any one of claims 12-16, wherein the first set of mandatory UE capability parameters comprises at least one of:

a maximum number of simultaneous CSI reference signals,

a total number ports of CSI reference signal,

simultaneous CSI reports,

a maximum number of synchronization signal/broadcast blocks (SSBs) , or

a parameter that is common for the first and second network devices.
A method comprising:

determining, at a first network device, that a terminal device is to be configured with a dual connectivity with the first network device and a second network device;

transmitting to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

receiving from the second network device a node addition response for the node addition request.
The method of claim 18, further comprising:

transmitting, at a first central unit (CU) of the first network device, a first request to a first distrusted unit (DU) of the first network device, the first request comprising a first information element which indicates that the terminal device is to be configured with the dual connectivity.
The method of claim 19, further comprising:

receiving, at the first CU, a first response from the first DU, the first response comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device, the first set of mandatory UE capability parameters being associated with a first set of carriers configured by the first DU for the terminal device.
The method of any one of claims 18-20, wherein the node addition response from the second network device comprises an indication regarding which resource to be downgraded for the first network device.
The method of claim 21, further comprising:

transmitting, at a first CU of the first network device, a second request to a first DU of the first network device, the second request comprising a second information element which comprises the indication regarding which resource to be downgraded for the first network device.
The method of claim 22, further comprising:

receiving, at the first CU, a second response from the first DU, the second response comprising a third set of mandatory UE capability parameters for the first network device and a fourth set of optional UE capability parameter for the first network device, and the third set of mandatory UE capability parameters and the fourth set of optional UE capability parameter being updated based on the indication.
The method of any one of claims 18-23, wherein the node addition request indicates a UE capability budget for the second network device.
The method of claim 24, wherein the node addition response indicates that the UE capability budget is accepted by the second network device, or

wherein the node addition response indicates a negotiation for the UE capability budget for the second network device.
The method of any one of claims 18-25, further comprising:

determining that a channel state information (CSI) reporting capability of the terminal device is to be exceeded; and

transmitting to the terminal device a configuration comprising a third information element which comprises a weight adjust factor for CSI reporting.
The method of any one of claims 18-25, wherein transmitting to the terminal device the configuration comprising the third information element comprises:

receiving, at the first CU, a third response from the first DU, the third response comprising the weight adjust factor for CSI reporting; and

transmitting, at the first CU and to the terminal device, the configuration comprising the third information element which comprises the weight adjust factor for CSI reporting.
The method of any one of claims 18-25, wherein the first set of mandatory UE capability parameters comprises at least one of:

a maximum number of simultaneous CSI reference signals,

a total number ports of CSI reference signal,

simultaneous CSI reports,

a maximum number of synchronization signal/broadcast blocks (SSBs) , or

a parameter that is common for the first and second network devices.
A method, comprising

receiving, at a second network device and from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

transmitting to the first network device a node addition response for the node addition request.
The method of claim 29, further comprising:

transmitting, at a second central unit (CU) of the second network device, a UE context setup request to a second distrusted unit (DU) of the second network device, the UE context setup request comprising the first set of mandatory UE capability parameters for the first network device and the second set of optional UE capability parameter for the first network device.
The method of claim 30, further comprising:

receiving, at the second CU, a UE context setup response from the second DU, the UE context setup response comprising an indication regarding which resource to be downgraded for the first network device.
The method of any one of claims 29-31, wherein the node addition request indicates a UE capability budget for the second network device.
The method of claim 32, wherein the node addition response indicates that the UE capability budget is accepted by the second network device, or

wherein the node addition response indicates a negotiation for the UE capability budget for the second network device.
The method of any one of claims 29-33, wherein the first set of mandatory UE capability parameters comprises at least one of:

a maximum number of simultaneous CSI reference signals,

a total number ports of CSI reference signal,

simultaneous CSI reports,

a maximum number of synchronization signal/broadcast blocks (SSBs) , or

a parameter that is common for the first and second network devices.
An apparatus comprises:

means for determining, at a first network device, that a terminal device is to be configured with a dual connectivity with the first network device and a second network device;

means for transmitting to the second network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

means for receiving from the second network device a node addition response for the node addition request.
An apparatus comprises:

means for receiving, at a second network device and from a first network device a node addition request comprising a first set of mandatory user equipment (UE) capability parameters for the first network device and a second set of optional UE capability parameter for the first network device; and

means for transmitting to the first network device a node addition response for the node addition request.
A computer readable medium comprising program instructions for causing an apparatus to perform the method of any one of claims 18-28, or any of one claims 29-34.