WO2020167198A1

WO2020167198A1 - Enhanced mobility load balancing (mlb) with beam-based load exchange

Info

Publication number: WO2020167198A1
Application number: PCT/SE2020/050057
Authority: WO
Inventors: Icaro L. J. Da Silva; Angelo Centonza; Pablo SOLDATI
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2019-02-11
Filing date: 2020-01-24
Publication date: 2020-08-20
Also published as: EP3925299A1

Abstract

Embodiments include methods, performed by a source node, for mobility load balancing (MLB) in a radio access network (RAN). Such methods include sending a resource information request, to a target node in the RAN, for information about resources, associated with the target node, that are usable for MLB operations in the RAN. The resource information request identifies at least one of the following: one or more first types of requested resource information; and one or more second types of resource granularity for which resource information is requested. Such methods include receiving one or more resource information reports, from the target node, including resource information according to one or more of the following: at least one of the first types, and at least one of the second types. Embodiments also include complementary methods performed by a target node, and source/target nodes configured to perform operations corresponding to such methods.

Description

ENHANCED MOBILITY LOAD BALANCING (MLB) WITH BEAM-

BASED LOAD EXCHANGE

TECHNICAL FIELD

The present application relates generally to the field of wireless communications, and more specifically to devices, methods, and computer-readable media that facilitate, enable, and/or improve mobility load balancing (MLB) between beams in a coverage area of a radio access network (RAN).

BACKGROUND

Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used. All references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc ., unless explicitly stated otherwise. The steps of any methods and/or procedures disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein can be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments can apply to any other embodiments, and vice versa. Other objectives, features and advantages of the enclosed embodiments will be apparent from the following description.

Long-Term Evolution (LTE is an umbrella term for so-called fourth-generation (4G) radio access technologies developed within the Third-Generation Partnership Project (3GPP) and initially standardized in Releases 8 and 9, also known as Evolved UTRAN (E-UTRAN). LTE is targeted at various licensed frequency bands and is accompanied by improvements to non-radio aspects commonly referred to as System Architecture Evolution (SAE), which includes Evolved Packet Core (EPC) network. LTE continues to evolve through subsequent releases that are developed according to standards-setting processes with 3 GPP and its working groups (WGs), including the Radio Access Network (RAN) WG, and sub-working groups (e.g, RANI, RAN2, etc.).

LTE Release 10 (Rel-10) supports bandwidths larger than 20 MHz. One important requirement on Rel-10 is to assure backward compatibility with LTE Release-8. As such, a wideband LTE Rel-10 carrier (e.g, wider than 20 MHz) should appear as a number of carriers to an LTE Rel-8 (“legacy”) terminal. Each such carrier can be referred to as a Component Carrier (CC). For an efficient use of a wide carrier also for legacy terminals, legacy terminals can be scheduled in all parts of the wideband LTE Rel-10 carrier. One exemplary way to achieve this is by means of Carrier Aggregation (CA), whereby a Rel-10 terminal can receive multiple CCs, each preferably having the same structure as a Rel-8 carrier. One of the enhancements in LTE Rel-11 is an enhanced Physical Downlink Control Channel (ePDCCH), which has the goals of increasing capacity and improving spatial reuse of control channel resources, improving inter-cell interference coordination (ICIC), and supporting antenna beamforming and/or transmit diversity for control channel. Furthermore, LTE Rel-12 introduced dual connectivity (DC) whereby a UE can be connected to two network nodes simultaneously, thereby improving connection robustness and/or capacity.

An overall exemplary architecture of a network comprising LTE and SAE is shown in Figure 1. E-UTRAN 100 comprises one or more evolved Node B’s (eNB), such as eNBs 105, 110, and 115, and one or more user equipment (UE), such as UE 120. As used within the 3 GPP standards,“user equipment” or“UE” means any wireless communication device ( e.g ., smartphone or computing device) that is capable of communicating with 3GPP- standard-compliant network equipment, including E-UTRAN as well as UTRAN and/or GERAN, as the third- (“3G”) and second-generation (“2G”) 3 GPP radio access networks are commonly known.

As specified by 3GPP, E-UTRAN 100 is responsible for all radio-related functions in the network, including radio bearer control, radio admission control, radio mobility control, scheduling, and dynamic allocation of resources to UEs in uplink and downlink, as well as security of the communications with the UE. These functions reside in the eNBs, such as eNBs 105, 110, and 1 15. The eNBs in the E-UTRAN communicate with each other via the XI interface, as shown in Figure 1. The eNBs also are responsible for the E-UTRAN interface to the EPC 130, specifically the SI interface to the Mobility Management Entity (MME) and the Serving Gateway (SGW), shown collectively as MME/S-GWs 134 and 138 in Figure 1. Generally speaking, the MME/S-GW handles both the overall control of the UE and data flow between the UE and the rest of the EPC. More specifically, the MME processes the signaling (e.g., control plane) protocols between the UE and the EPC, which are known as the Non- Access Stratum (NAS) protocols. The S-GW handles all Internet Protocol (IP) data packets (e.g., data or user plane) between the UE and the EPC, and serves as the local mobility anchor for the data bearers when the UE moves between eNBs, such as eNBs 105, 110, and 115. EPC 130 can also include a Home Subscriber Server (HSS) 131, which manages user- and subscriber-related information. HSS 131 can also provide support functions in mobility management, call and session setup, user authentication and access authorization. The functions of HSS 131 can be related to the functions of legacy Home Location Register (HLR) and Authentication Centre (AuC) functions or operations.

In some embodiments, HSS 131 can communicate with a user data repository (UDR) - labelled EPC-UDR 135 in Figure 1 - via a Ud interface. The EPC-UDR 135 can store user credentials after they have been encrypted by AuC algorithms. These algorithms are not standardized (i.e., vendor-specific), such that encrypted credentials stored in EPC-UDR 135 are inaccessible by any other vendor than the vendor of HSS 131.

Figure 2A shows a high-level block diagram of an exemplary LTE architecture in terms of its constituent entities - UE, E-UTRAN, and EPC - and high-level functional division into the Access Stratum (AS) and the Non-Access Stratum (NAS). Figure 2A also illustrates two particular interface points, namely Uu (UE/E-UTRAN Radio Interface) and SI (E-UTRAN/EPC interface), each using a specific set of protocols, i.e., Radio Protocols and SI Protocols. Although not shown in Figure 2A, each of the protocol sets can be further segmented into user plane and control plane protocol functionality. The user and control planes are also referred to as U-plane and C-plane, respectively. On the Uu interface, the U- plane carries user information ( e.g ., data packets) while the C-plane carries control information between UE and E-UTRAN.

Figure 2B illustrates a block diagram of an exemplary C-plane protocol stack between a UE, an eNB, and an MME. The exemplary protocol stack includes Physical (PHY), Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (RRC) layers between the UE and eNB. The PHY layer is concerned with how and what characteristics are used to transfer data over transport channels on the LTE radio interface. The MAC layer provides data transfer services on logical channels, maps logical channels to PHY transport channels, and reallocates PHY resources to support these services. The RLC layer provides error detection and/or correction, concatenation, segmentation, and reassembly, reordering of data transferred to or from the upper layers. The PHY, MAC, and RLC layers perform identical functions for both the U- plane and the C-plane. The PDCP layer provides ciphering/deciphering and integrity protection for both U-plane and C-plane, as well as other functions for the U-plane such as header compression. The exemplary protocol stack also includes non-access stratum (NAS) signaling between the UE and the MME. Figure 2C shows a block diagram of an exemplary LTE radio interface protocol architecture from the perspective of the PHY layer. The interfaces between the various layers are provided by Service Access Points (SAPs), indicated by the ovals in Figure 2C. The PHY layer interfaces with the MAC and RRC protocol layers described above. The PHY, MAC, and RRC are also referred to as Layers 1-3, respectively, in the figure. The MAC provides different logical channels to the RLC protocol layer (also described above), characterized by the type of information transferred, whereas the PHY provides a transport channel to the MAC, characterized by how the information is transferred over the radio interface. In providing this transport service, the PHY performs various functions including error detection and correction; rate-matching and mapping of the coded transport channel onto physical channels; power weighting, modulation, and demodulation of physical channels; transmit diversity; and beamforming multiple input multiple output (MIMO) antenna processing. The PHY layer also receives control information ( e.g ., commands) from RRC and provides various information to RRC, such as radio measurements.

The RRC layer controls communications between a UE and an eNB at the radio interface, as well as the mobility of a UE between cells in the E-UTRAN. After a UE is powered ON it will be in the RRC__IDLE state until an RRC connection is established with the network, at which time the UE will transition to RRC CONNECTED state (e.g., where data transfer can occur). The UE returns to RRC IDLE after the connection with the network is released. In RRC IDLE state, the UE’s radio is active on a discontinuous reception (DRX) schedule configured by upper layers. During DRX active periods (also referred to as“On durations”), an RRC IDLE UE receives system information (SI) broadcast by a serving cell, performs measurements of neighbor cells to support cell reselection, and monitors a paging channel on PDCCH for pages from the EPC via eNB. An RRC IDLE UE is known in the EPC and has an assigned IP address, but is not known to the serving eNB (e.g, there is no stored context).

Generally speaking, a physical channel corresponds a set of resource elements carrying information that originates from higher layers. Downlink (i.e., eNB to UE) physical channels provided by the LTE PHY include Physical Downlink Shared Channel (PDSCH), Physical Multicast Channel (PMCH), Physical Downlink Control Channel (PDCCH), Relay Physical Downlink Control Channel (R-PDCCH), Physical Broadcast Channel (PBCH), Physical Control Format Indicator Channel (PCFICH), and Physical Hybrid ARQ Indicator Channel (PHICH). In addition, the LTE PHY downlink includes various reference signals, synchronization signals, and discovery signals. PBCH carries the basic system information, required by the UE to access the network. PDSCH is the main physical channel used for unicast DL data transmission, but also for transmission of RAR (random access response), certain system information blocks, and paging information. PHICH carries HARQ feedback ( e.g ., ACK/NAK) for UL transmissions by the UEs. Similarly, PDCCH carries DL scheduling assignments (e.g., for PDSCH), UL resource grants (e.g, for PUSCH), channel quality feedback (e.g, CSI) for the UL channel, and other control information.

Uplink (i.e., UE to eNB) physical channels provided by the LTE PHY include Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), and Physical Random Access Channel (PRACH). In addition, the LTE PHY uplink includes various reference signals including demodulation reference signals (DM-RS), which are transmitted to aid the eNB in the reception of an associated PUCCH or PUSCH; and sounding reference signals (SRS), which are not associated with any uplink channel.

PRACH is used for random access preamble transmission. PUSCH is the counterpart of PDSCH, used primarily for unicast UL data transmission. Similar to PDCCH, PUCCH carries uplink control information (UCI) such as scheduling requests, CSI for the DL channel, HARQ feedback for eNB DL transmissions, and other control information.

The multiple access scheme for the LTE PHY is based on Orthogonal Frequency Division Multiplexing (OFDM) with a cyclic prefix (CP) in the downlink, and on Single- Carrier Frequency Division Multiple Access (SC-FDMA) with a cyclic prefix in the uplink. To support transmission in paired and unpaired spectrum, the LTE PHY supports both Frequency Division Duplexing (FDD) (including both full- and half-duplex operation) and Time Division Duplexing (TDD). The LTE FDD downlink (DL) radio frame has a fixed duration of 10 ms and consists of 20 slots, labeled 0 through 19, each with a fixed duration of 0.5 ms. A 1-ms subframe comprises two consecutive slots where subframe / consists of slots 2i and 2/ + l Each exemplary FDD DL slot consists of N^DL _symb OFDM symbols, each of which is comprised of N_sc OFDM subcarriers. Exemplary values of N^DL _symb can be 7 (with a normal CP) or 6 (with an extended-length CP) for subcarrier bandwidth of 15 kHz. The value of N_sc is configurable based upon the available channel bandwidth. Since persons of ordinary skill in the art are familiar with the principles of OFDM, further details are omitted in this description. Furthermore, a combination of a particular subcarrier in a particular symbol is known as a resource element (RE). Each RE is used to transmit a particular number of bits, depending on the type of modulation and/or bit-mapping constellation used for that RE. For example, some REs may carry two bits using QPSK modulation, while other REs may carry four or six bits using 16- or 64-QAM, respectively. The radio resources of the LTE PHY are also defined in terms of physical resource blocks (PRBs). A PRB spans N^RB _SC sub-carriers over the duration of a slot (i.e., N^DL _symb symbols), where Nⁱ _se is typically either 12 (with a 15-kHz sub-carrier bandwidth) or 24 (7.5-kHz bandwidth). A PRB spanning the same N^RB _SC subcarriers during an entire subframe (i.e., 2N^DL _symb symbols) is known as a PRB pair. Accordingly, the resources available in a subframe of the LTE PHY DL comprise N^DLRB PRB pairs, each of which comprises 2N^DL _symb* N^RB _SC REs. For a normal CP and 15-KHz sub carrier bandwidth, a PRB pair comprises 168 REs.

The LTE FDD uplink (UL) radio frame is configured in a similar manner as the exemplary FDD DL radio frame discussed above. Using terminology consistent with the above DL description, each UL slot consists of N^UL _symb OFDM symbols, each of which is comprised of N_sc OFDM subcarriers.

As discussed above, the LTE PHY maps the various DL and UL physical channels to the PHY resources. For example, the PHICH carries HARQ feedback (e.g., ACK/NAK) for UL transmissions by the UEs. Similarly, PDCCH carries scheduling assignments, channel quality feedback (e.g, CSI) for the UL channel, and other control information. Likewise, a PUCCH carries uplink control information such as scheduling requests, CSI for the downlink channel, HARQ feedback for network node DL transmissions, and other control information. Both PDCCH and PUCCH can be transmitted on aggregations of one or several consecutive control channel elements (CCEs), and a CCE is mapped to the physical resource based on resource element groups (REGs), each of which is comprised of a plurality of REs. For example, a CCE can comprise nine (9) REGs, each of which can comprise four (4) REs.

In LTE, DL transmissions are dynamically scheduled, i.e., in each subframe the base station transmits control information indicating the terminal to which data is transmitted and upon which resource blocks the data is transmitted, in the current downlink subframe. This control signaling is typically transmitted in the first n OFDM symbols in each subframe and the number n (=1,2,3 or 4) is known as the Control Format Indicator (CFI) indicated by the PCFICH transmitted in the first symbol of the control region.

Within the LTE DL, certain REs within each LTE subframe are reserved for the transmission of reference signals, such as DM-RS mentioned above. For example, DM-RS can be carried in OFDM symbols in the sixth, seventh, thirteenth, and fourteenth symbols of the OFDM subframe, with the respective DM-RS REs distributed in the frequency domain within each of the symbols. In addition, the DM-RS REs are divided into two code division multiplexing (CDM) groups referred to as CDM Groups 1 and 2. In LTE systems supporting transmission ranks 1-4, both CDM groups are used in combination with length-2 orthogonal cover codes OCCs. The OCCs are applied to clusters of two adjacent (i.e., in time domain) reference symbols in the same subcarrier in the frequency domain.

To support mobility ( e.g ., handover or reselection) between cells and/or beams, a UE can perform periodic cell search and measurements of signal power (e.g., reference signal received power, RSRP), signal quality (e.g, reference signal received quality, RSRQ), and/or signal-to-interference-plus-noise ratio (SINR) in both RRC CONNECTED and RRC IDLE states. A UE is responsible for detecting new neighbor cells, and for tracking and monitoring already detected cells. An LTE UE can perform such measurements on various downlink reference signals (RS) including, e.g, cell-specific Reference Signal (CRS), MBSFN reference signals, UE-specific DM-RS associated with PDSCH, DM-RS associated with (e/M/N)PDCCH, Positioning Reference Signal (PRS), and CSI Reference Signal (CSI-RS).

Detected cells and measurement values associated with monitored and/or detected cells are reported to the network. Reports to the network can be configured to be periodic or aperiodic based a particular event. Such reports are commonly referred to as mobility measurement reports and contain channel state information (CSI). These reports can be used, e.g, to make decisions on UE mobility (e.g., handover) and/or dynamic activation or deactivation of SCells in a UE’s carrier aggregation (CA) configuration.

In general, a radio access node contemplating handover of one or more served UEs to various neighbour (or“target”) cells has cell-level load information for the respective neighbour cells. However, a neighbour cell’s load distribution in the spatial domain is rarely uniform. This spatial load variation in a cell can create various problems, challenges, difficulties, and/or issues for load balancing in wireless networks.

SUMMARY

Accordingly, exemplary embodiments of the present disclosure address these and other mobility-related issues in wireless communication networks by providing improvements to beam-level mobility operations, such as handovers (including conditional handovers) between one or more beams of a source node and one or more beams of a target node. Exemplary embodiments of the present disclosure include methods (e.g., procedures) for beam-level mobility load balancing (MLB) in a radio access network (RAN). These exemplary methods can be performed by a source node (e.g., base station, eNB, gNB, etc. or component thereof, such as a gNB-CU or gNB-DU) in the RAN, serving one or more user equipment (UEs, e.g., wireless devices, MTC devices, NB-IoT devices, modems, etc. or components thereof) with one or more beams and/or cells.

In some embodiments, these exemplary methods can include receiving one or more measurement reports from a plurality of UEs. Each measurement report can include radio measurements related to a source beam or a source cell associated with the source node and/or one or more target beams associated with one or more target nodes in the RAN.

In some embodiments, the source node can have a split CU-DU architecture. In such embodiments, these exemplary methods can include receiving resource requests from one or more distributed units (DUs) associated with the source node central unit (CU), and aggregating the resource requests into a resource information request for the target node. Such operations can be performed by the source node CU.

These exemplary methods can also include sending a resource information request, to a target node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN. The resource information request can identify at least one of the following: one or more first types of requested resource information; and one or more second types of resource granularity for which resource information is requested. In some embodiments, the resource information request can be based on the received measurement reports from the UEs.

In some embodiments, the first types of resource information can include one or more of the following:

• traffic load information,

• utilization of time-frequency resources,

• available capacity,

• number of user equipment (UEs), and

• number of UEs in RRC CONNECTED mode.

Likewise, in some embodiments, the second types of resource granularity can include one or more of the following, including combinations thereof:

• per SS/PBCH block (SSB) beam,

• per channel state information reference signal (CSI-RS) beam, • per link beam,

• per bandwidth part (BWP),

• per network slice, and

• per traffic type.

In some embodiments, the resource information request can also identify one or more of the following for which resource information is requested: one or more specific beams or specific groups of beams associated with the target node; one or more cells associated with the specific beams or specific groups of beams; one or more of the first types; one or more specific types of traffic; and one or more specific network slices. In some embodiments, the resource information request can also identify a frequency or periodicity and/or timing of resource information reports from the target node. In some embodiments, these exemplary methods can include receiving, from the target node, a response acknowledging that resource information reports will be sent as requested by the source node.

These exemplary methods can also include receiving one or more resource information reports, from the target node, including resource information according to at least one of the first types and/or at least one of the second types identified in the resource information request. In some embodiments, the resource information in each resource information report can include one or more of the following:

• available capacity for one or more specific SSB beams or specific groups of SSB beams associated with the target node;

• available capacity in a specific SSB beam for one or more specific network slices;

• available capacity in a cell for one or more specific network slices; and

• utilization of time-frequency resources for one or more specific SSB beams or

specific groups of SSB beams associated with the target node.

In embodiments where the source node has a split CU-DU architecture, these exemplary methods can include splitting each of the resource information reports (e.g., received from the target node) into a plurality of further resource information reports, each further resource information report associated with a different one of the DUs. In such embodiments, the source node can send the further resource information reports to the respective DUs. Such operations can be performed by a CU of the source node. In some embodiments, the target node can be a further CU (e.g., part of a different gNB than the source node) or a further DU associated with the CU of the source node (e.g., part of the same gNB as the source node). In some embodiments, these exemplary methods can also include selecting at least one of the target beams for handover of a subset of the first plurality of UEs from the source beam. This selection can be based on the received resource information reports and, in some embodiments, the received UE measurement reports.

In some embodiments, these exemplary methods can also include performing a handover procedure with the target node with respect to the subset of UEs. In some embodiments, performing the handover procedure can include sending, to the target node, an indication that a particular UE, of the subset of UEs, should be handed over to the selected target beams. In such embodiments, the selected target beams are respective SSBs having respective SSB coverage areas and associated with respective SSB indices. Furthermore, the indication includes the respective SSB indices and indicates that the particular UE should be handed over to respective link beams having coverage areas overlapping with the SSB coverage areas. In the case where the subset of UEs includes a plurality of UEs, the source node can send such an indication for each of the UEs individually.

Other exemplary embodiments of the present disclosure include additional methods (e.g., procedures) for beam-level mobility load balancing (MLB) in a radio access network (RAN). These exemplary methods can be performed by a target node (e.g., base station, eNB, gNB, etc. or component thereof, such as a gNB-CU or gNB-DU) in the RAN that utilizes beams to communicate with UEs.

These exemplary methods can include receiving a resource information request, from a source node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN. The resource information request can identify at least one of the following: one or more first types of requested resource information; and one or more second types of resource granularity for which resource information is requested.

• traffic load information,

• utilization of time-frequency resources,

• available capacity,

• number of user equipment (UEs), and

• number of UEs in RRC CONNECTED mode. Likewise, in some embodiments, the second types of resource granularity can include one or more of the following, including combinations thereof:

• per SS/PBCH block (SSB) beam,

• per channel state information reference signal (CSI-RS) beam,

• per link beam,

• per bandwidth part (BWP),

• per network slice, and

• per traffic type.

In some embodiments, the resource information request can also identify one or more of the following for which resource information is requested: one or more specific beams or specific groups of beams associated with the target node; one or more cells associated with the specific beams or specific groups of beams; one or more of the first types; one or more specific types of traffic; and one or more specific network slices. In some embodiments, the resource information request can also identify a frequency or periodicity and/or timing of resource information reports (e.g., to the source node in response to the request). In some embodiments, these exemplary methods can include sending, to the source node, a response acknowledging that resource information reports will be sent as requested by the source node.

In some embodiments, the response also indicates at least one of the following that can be, or will be, included in the resource information reports: one or more first types of resource information, and one or more second types of resource granularity for the resource information. For example, the one or more first types and/or one or more second types indicated in the response can be different from the one or more first types and/or one or more second types indicated in the resource information request.

In some embodiments, these exemplary methods can include configuring measurements by a second plurality of UEs based on the resource information request from the source node, and receiving measurement reports from the second plurality of UEs in response to the configured measurements. Each measurement report can include radio measurements related to a plurality of target beams associated with the target node. These exemplary methods can also include determining resource information, to be included in the resource information reports, based on the measurement reports.

In some embodiments, each measurement report can include signal strengths for the plurality of target beams. In such embodiments, determining resource information can include, for each particular UE of the second plurality of UEs, associating the particular UE with the target beam for which the particular UE reports the highest signal strength, and correlating the particular UE’s associated target beam with resources scheduled by the target node for the particular UE and/or a traffic type requested by the particular UE.

In some embodiments, the target node can have a split CU-DU architecture. In such embodiments, determining the resource information can be performed by a central unit (CU) of the target node, and can include splitting the resource information request into a plurality of further resource information requests for a respective plurality of distributed units (DUs) associated with the CU. In addition, the target node (i.e., the CU) can send the further resource information requests to the respective DUs, receive a plurality of responses for the respective DUs, and aggregate the plurality of responses into resource information, e.g., to be included in resource information reports sent to the source node. In some embodiments, the source node can be a further CU (e.g., part of a different gNB than the target node) or a further DU associated with the CU of the target node (e.g., part of the same gNB as the target node).

These exemplary methods can also include sending one or more resource information reports, to the source node, including resource information according to at least one of the first types and/or at least one of the second types identified in the resource information request. In some embodiments, the resource information in each resource information report can include one or more of the following:

• available capacity in a cell for one or more specific network slices; and

specific groups of SSB beams associated with the target node.

In some embodiments, these exemplary methods can also include performing a handover procedure with the source node with respect to one or more UEs served by a source beam associated with the source node. In some embodiments, performing the handover procedure can include receiving, from the source node, an indication that a particular one of the UEs should be handed over to at least one of the target beams associated with the target node. In such embodiments, the at least one target beams are respective SSBs having respective SSB coverage areas and associated with respective SSB indices. Furthermore, the indication includes the respective SSB indices and indicates that the particular UE should be handed over to respective link beams having coverage areas overlapping with the SSB coverage areas. In the case where the one or more UEs includes a plurality of UEs, the target node can receive the indication for each of the UEs individually.

Other exemplary embodiments include network nodes (e.g., base stations, eNBs, gNBs, etc. or components thereof, such as gNB-CUs or gNB-DUs) configured to perform operations corresponding to any of the exemplary methods described herein. Other exemplary embodiments include non-transitory, computer-readable media storing computer-executable instructions that, when executed by processing circuitry comprising a network node, configure the network node to perform operations corresponding to any of the exemplary methods described herein.

These and other objects, features, benefits, and/or advantages of embodiments of the present disclosure will become apparent upon reading the following Detailed Description in view of the Drawings briefly described below.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a high-level block diagram of an exemplary architecture of the Long-Term Evolution (LTE) Evolved UTRAN (E-UTRAN) and Evolved Packet Core (EPC) network, as standardized by 3 GPP.

Figure 2A is a high-level block diagram of an exemplary E-UTRAN architecture in terms of its constituent components, protocols, and interfaces.

Figure 2B is a block diagram of exemplary protocol layers of the control-plane portion of the radio (Uu) interface between a user equipment (UE) and the E-UTRAN.

Figure 2C is a block diagram of an exemplary LTE radio interface protocol architecture from the perspective of the PHY layer.

Figures 3-4 show two high-level view of an exemplary 5G network architecture.

Figure 5 shows an exemplary Mobility Setting Change procedure.

Figure 6 shows an exemplary variation of cell load vs. time, with an exemplary predefined load threshold.

Figure 7 illustrates an exemplary LTE mobility load balancing (MLB) scenario involving three (3) eNBs.

Figure 8 shows an exemplary configuration of a UE measurement model for NR.

Figure 9 illustrates an exemplary arrangement where a cell includes 65 different downlink beams associated with SSB indices 0-64 respectively. Figure 10 shows an exemplary handover scenario of a UE from a beam of a source cell to one beam of a target cell.

Figure 11 shows an exemplary scenario involving a non-uniform distribution of UEs within beams of a cell.

Figure 12 shows a signaling flow of a dedicated procedure for beam-level mobility load balancing (MLB) in a RAN, according to various exemplary embodiments of the present disclosure.

Figure 13 is a signalling flow diagram illustrating successful initiation of resource status reporting between two network nodes (e.g., gNBs), according to various exemplary embodiments of the present disclosure.

Figure 14 is a signalling flow diagram illustrating successful resource status reporting between two LTE network nodes (e.g., eNBs), according to various exemplary embodiments of the present disclosure.

Figure 15 illustrates an exemplary tabular encoding for the resource information reported between two network nodes (such as shown in Figure 14), according to various exemplary embodiments of the present disclosure.

Figure 16 illustrates an exemplary method (e.g., procedure) performed by a source node in a radio access network (RAN, e.g., E-UTRAN, NG-RAN), according to various exemplary embodiments of the present disclosure.

Figure 17 illustrates an exemplary method (e.g., procedure) performed by a target node in a RAN (e.g., NG-RAN), according to various exemplary embodiments of the present disclosure.

Figure 18 illustrates an exemplary embodiment of a wireless network, in accordance with various aspects described herein.

Figure 19 illustrates an exemplary embodiment of a UE, in accordance with various aspects described herein.

Figure 20 is a block diagram illustrating an exemplary virtualization environment usable for implementation of various embodiments of network nodes described herein.

Figures 21-22 are block diagrams of various exemplary communication systems and/or networks, according to various exemplary embodiments of the present disclosure.

Figures 23-26 are flow diagrams of exemplary methods for transmission and/or reception of user data, according to various exemplary embodiments of the present disclosure. DETAILED DESCRIPTION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art. Furthermore, the following terms are used throughout the description given below:

• Radio Node: As used herein, a“radio node” can be either a“radio access node” or a “wireless device.”

• Radio Access Node: As used herein, a“radio access node” (or“radio network node”) can be any node in a radio access network (RAN) of a cellular communications network that operates to wirelessly transmit and/or receive signals. Some examples of a radio access node include, but are not limited to, a base station ( e.g ., a New Radio (NR) base station (gNB) in a 3GPP Fifth Generation (5G) NR network or an enhanced or evolved Node B (network node) in a 3 GPP LTE network), a high-power or macro base station, a low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), an integrated access backhaul (LAB) node, and a relay node.

• Core Network Node: As used herein, a“core network node” is any type of node in a core network. Some examples of a core network node include, e.g, a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), or the like.

• Wireless Device: As used herein, a“wireless device” (or“WD” for short) is any type of device that has access to (i.e., is served by) a cellular communications network by communicate wirelessly with network nodes and/or other wireless devices. Communicating wirelessly can involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. Unless otherwise noted, the term“wireless device” is used interchangeably herein with“user equipment” (or“UE” for short). Some examples of a wireless device include, but are not limited to, a UE in a 3GPP network and a Machine Type Communication (MTC) device. Communicating wirelessly can involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. i6

• Network Node: As used herein, a“network node” is any node that is either part of the radio access network or the core network of a cellular communications network. Functionally, a network node is equipment capable, configured, arranged, and/or operable to communicate directly or indirectly with a wireless device and/or with other network nodes or equipment in the cellular communications network, to enable and/or provide wireless access to the wireless device, and/or to perform other functions ( e.g ., administration) in the cellular communications network.

Note that the description given herein focuses on a 3 GPP cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system. Other wireless systems, including without limitation Wide Band Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMax), Ultra Mobile Broadband (UMB) and Global System for Mobile Communications (GSM), may also benefit from the concepts, principles, and/or embodiments described herein.

In addition, functions and/or operations described herein as being performed by a wireless device or a network node may be distributed over a plurality of wireless devices and/or network nodes. Furthermore, although the term“cell” is used herein, it should be understood that (particularly with respect to 5G R) beams may be used instead of cells and, as such, concepts described herein apply equally to both cells and beams.

As discussed above, a radio access node contemplating handover of one or more served UEs to various neighbor (or“target”) cells has cell-level load information for the respective neighbor cells. However, a neighbor cell’s load distribution in the spatial domain is rarely uniform. This spatial load variation in a cell can create various problems, challenges, difficulties, and/or issues for load balancing in wireless networks. These aspects are discussed in more detail below, along with exemplary solutions provided by embodiments of the present disclosure.

While LTE was primarily designed for user-to-user communications, 5G (also referred to as“NR”) cellular networks are envisioned to support both high single-user data rates (e.g., 1 Gb/s) and large-scale, machine-to-machine (M2M) communication involving short, bursty transmissions from many different devices that share the frequency bandwidth. The 5G radio interface (also referred to as“New Radio” or“NR”) targets a wide range of data services including eMBB (enhanced Mobile Broad Band) and URLLC (Ultra-Reliable Low Latency Communication). These services can have different requirements and objectives. For example, URLLC is intended to provide a data service with extremely strict error and latency requirements, e.g ., error probabilities as low as 10^-5 or lower and 1 ms end- to-end latency or lower. For eMBB, the requirements on latency and error probability can be less stringent whereas the required supported peak rate and/or spectral efficiency can be higher.

Similar to LTE, NR uses CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) in the downlink and both CP-OFDM and DFT-spread OFDM (DFT-S-OFDM) in the uplink. In the time domain, NR downlink and uplink physical resources are organized into equally-sized, 1-ms subframes. Each subframe includes one or more slots, and each slot includes 14 (for normal cyclic prefix) or 12 (for extended cyclic prefix) time-domain symbols. Similar to LTE, NR data scheduling is done on a per-slot basis.

In addition, NR includes a Type-B scheduling, also known as“mini-slots.” These are shorter than slots, typically ranging from one symbol up to one less than the number of symbols in a slot and can start at any symbol of a slot. Mini-slots can be used if the transmission duration of a slot is too long and/or the occurrence of the next slot start (slot alignment) is too late.

Figure 3 shows a high-level view of an exemplary 5G network architecture, including a Next Generation Radio Access Network (NG-RAN) 399 and a 5G Core (5GC) 398. As shown in the figure, NG-RAN 399 can include gNBs 310 (e.g., 310a,b) and ng-eNBs 320 (e.g., 320a, b) that are interconnected with each other via respective Xn interfaces. The gNBs and ng-eNBs are also connected via the NG interfaces to 5GC 398, more specifically to the AMF (Access and Mobility Management Function) 230 (e.g., AMFs 230a, b) via respective NG-C interfaces and to the UPF (User Plane Function) 240 (e.g., UPFs 240a, b) via respective NG-U interfaces.

Each of the gNBs 310 can support the NR radio interface, including frequency division duplexing (FDD), time division duplexing (TDD), or a combination thereof. In contrast, each of ng-eNBs 320 supports the LTE radio interface but, unlike conventional LTE eNBs (such as shown in Figure 1), connect to the 5GC via the NG interface.

Figure 4 illustrates another high-level view of an exemplary 5G network architecture. The network shown in Figure 4 includes NG-RAN 499 and 5GC 498, which can be similar to NG-RAN 399 and 5GC 398 illustrated in Figure 3. More specifically, NG-RAN 499 can include gNBs connected to the 5GC via one or more NG interfaces, such as gNBs 400, 450 connected via interfaces 402, 452, respectively. In addition, the gNBs can be connected to i8

each other via one or more Xn interfaces, such as Xn interface 440 between gNBs 400 and 450.

In the split-RAN architecture shown in Figure 4, NG-RAN nodes include a CU (or gNB-CU) and one or more DUs (or gNB-DUs). For example, gNB 400 in Figure 4 includes gNB-CU 410 and gNB-DUs 420 and 430. CUs (e.g., gNB-CU 410) are logical nodes that host higher-layer protocols and perform various gNB functions such controlling the operation of DUs. Likewise, DUs are logical nodes that host lower-layer protocols and can include, depending on the functional split, various subsets of the gNB functions. As such, each of the CUs and DUs can include various circuitry needed to perform their respective functions, including processing circuitry, interface and/or transceiver circuitry (e.g., for communication), and power supply circuitry. Moreover, the terms“central unit” and“centralized unit” are used interchangeably herein, as are the terms“distributed unit” and“decentralized unit.”

A gNB-CU connects to gNB-DUs over respective FI logical interfaces, such as interfaces 422 and 432 shown in Figure 4. The gNB-CU and connected gNB-DUs are only visible to other gNBs and the 5GC as a gNB, e.g., the FI interface is not visible beyond gNB- CU. As briefly mentioned above, a CU can host higher-layer protocols such as, e.g., FI application part protocol (Fl-AP), Stream Control Transmission Protocol (SCTP), GPRS Tunneling Protocol (GTP), Packet Data Convergence Protocol (PDCP), User Datagram Protocol (UDP), Internet Protocol (IP), and Radio Resource Control (RRC) protocol. In contrast, a DU can host lower-layer protocols such as, e.g., Radio Link Control (RLC), Medium Access Control (MAC), and physical-layer (PHY) protocols.

Other variants of protocol distributions between CU and DU can exist, however, such as hosting the RRC, PDCP and part of the RLC protocol in the CU (e.g, Automatic Retransmission Request (ARQ) function), while hosting the remaining parts of the RLC protocol in the DU, together with MAC and PHY. In some embodiments, the CU can host RRC and PDCP, where PDCP is assumed to handle both UP traffic and CP traffic. Nevertheless, other exemplary embodiments may utilize other protocol splits that by hosting certain protocols in the CU and certain others in the DU. Exemplary embodiments can also locate centralized control plane protocols (e.g, PDCP-C and RRC) in a different CU with respect to the centralized user plane protocols (e.g, PDCP-U).

As mentioned above, a UE in RRC CONNECTED mode can be configured by the network to perform measurements and send measurement reports to the network node hosting its current serving cell. For example, the network can configure a UE to perform measurements on various carrier frequencies and various radio access technologies (RATs) corresponding to neighbor cells, as well as for various purposes including, e.g ., mobility and positioning. The configuration for each of these measurements is referred to as a “measurement object.” Furthermore, the UE can be configured to perform the measurements according to a“measurement gap pattern” (or“gap pattern” for short), which can comprise a measurement gap repetition period (MGRP) (i.e., how often a regular gap available for measurements occurs) and a measurement gap length (MGL) (i.e., the length of each gap).

Upon receiving measurement reports that meet predetermined triggering criteria, the network may send a handover command to the UE. In LTE, this command is an RRConnectionReconfiguration message with a mobilityControlInfo field. In NR, this command is an RRCReconfiguration message with a reconfigurationWithSync field.

The basic mobility solution in NR shares some similarities to LTE. The UE may be configured by the network to perform cell measurements and report them, to assist the network to take mobility decisions. However, an NR UE may be configured to perform L3 beam measurements based on different reference signals and report them for each cell (serving and non-serving/candidate) fulfilling triggering conditions for measurement report (e.g., an “A3 event”). In particular, NR UEs can be configured to perform/report measurements on SS/PBCH blocks (SSBs) in addition to the reference signals measured/reported by LTE UEs (e.g., CSI-RS). Each SSB is carried in four (4) adjacent OFDM symbols, and comprises a combination of primary synchronization signal (PSS), secondary synchronization signal (SSS), DM-RS, and physical broadcast channel (PBCH).

As described in 3 GPP TS 38.300 (vl5.4.0), an NR UE in RRC CONNECTED mode measures one or more detected beams of a cell and then averages the measurements results (e.g., power values) to derive the cell quality. In doing so, the UE is configured to consider a subset of the detected beams. Filtering takes place at two different levels: at the physical layer to derive beam quality and then at RRC level to derive cell quality from multiple beams. Cell quality from beam measurements is derived in the same way for the serving cell(s) and for the non-serving/candidate cell(s). Measurement reports may contain the measurement results of the Xbest beams if the UE is configured to do so by the gNB.

In the present disclosure, the term“beam” is used to refer to the coverage area of a reference signal that may be measured by a UE. In NR, for example, such reference signals can include any of the following, alone or in combination: SSB; CSI-RS; tertiary reference signal (or any other sync signal); PRS; DM-RS; and any other reference signal that may be beamformed for transmission. Such beams can be correlated and/or coextensive with other beams used by eNBs or gNBS to transmit and/or receive physical data channels (e.g., PDSCH, PUSCH) and/or physical control channels (e.g., PDCCH, PUCCH).

In making handover (and, more generally, mobility) decisions for individual UEs, the network takes into account not only the UE -reported measurements but also the load of the respective cells in the network. In the present disclosure, the term“load” (or equivalently “load information” or“load-related information”) can refer to a measure of resources being consumed (e.g., by the respective cells) or a measure of an available capacity (e.g., remaining in the respective cells). The loads of cells served by a radio access node are typically measured frequently. When the load of a cell exceeds a pre-configured threshold, procedures can be triggered to transfer some UE traffic from the overloaded cell to either a neighbor cell of the same radio access technology (RAT), a different RAT, a different frequency, etc.

Put differently, a mobility load balancing (MLB) algorithm running at a radio access node (e.g., eNB or gNB) has to decide which UEs will be handed over (“UE selection”) and to which neighbor cells (“cell selection”). These decisions are typically made based on the load reports and any available radio measurements of source cell and neighbor cells, such as measurements reported by UEs operating in RRC CONNECTED and RRC IDLE states.

In general, a radio access node contemplating handover of one or more served UEs to various neighbour (or“target”) cells has cell-level load information for the respective neighbour cells. However, a neighbour cell’s load distribution in the spatial domain is rarely uniform. For example, when a network node uses beamforming, the coverage of a cell may be further divided into the coverage of different beams. In such case, the load distribution among the beams of a cell will typically be non-uniform and, in some cases, can vary significantly from beam to beam. This beam-level variation in a cell can create various problems, challenges, difficulties, and/or issues for MLB in wireless networks.

Figure 5 shows an exemplary Mobility Setting Change procedure (e.g., as specified by 3GPP TS 36.423), which can be run before or after a MLB handover is performed. This procedure is aimed at negotiating, between a source cell and potential target cell, a change on the *Handover Trigger event, which is used to trigger the UE mobility from one cell to another. As an example, consider the case where the Mobility Setting Change is performed after the HO. Once the source eNB has selected the target eNB and which UE’s will be offloaded, it performs a Mobility Setting Change. During this procedure, new mobility settings are negotiated between the source and target eNBs so that the UE’s handed over due to MLB will not be immediately handed over back to the source cell. The procedure can either be followed or preceded by ordinary handovers, depending on the vendor implementation. Currently, 3GPP specifies the following components and/or functions for MLB in LTE networks: 1) load reporting; 2) load balancing action based on handovers; and 3) adapting handover (HO) and/or cell reselection (CR) configuration so that load remains balanced. The load reporting function is executed by exchanging cell specific load information between neighbor enhanced NodeBs (eNBs) over the X2 (intra-LTE scenario) or SI (inter-RAT scenario) interfaces. In the case of intra-LTE load balance, the source eNB may trigger a RESOURCE STATUS REQUEST message to potential target eNBs at any point in time, for example when the load is above a pre-defmed value and/or threshold. Figure 6 is a graph showing an exemplary variation of cell load vs. time, with an exemplary predefined load threshold (i.e., Lte load threshold).

Figure 7 illustrates an exemplary LTE MLB scenario involving three (3) eNBs. In this scenario, eNB l serves cells A1 and B l, eNB2 serves cells A2 and B2, and eNB3 serves cells A3, B3, and C3. Furthermore, eNB2 and eNB3 periodially report load values for their served cells to eNBl . In addition, UEs operating in a cell served by eNBl (e.g., Al) may send measurement reports (RSRP, RSRQ, SINR, etc.) to eNBl for one or more neighbour cells (e.g. A2, B3). Based on these reports and the received load information for neighbor cells, eNB l may decide to handover one or more UE from Al to a neighbour cell such as B3 or A2. When eNBl decides to offload a UE (e.g., to A2), it triggers an ordinary handover, including a handover preparation with a selected target node (e.g., eNB2). This can also include a Mobility Setting Change for the offloaded UE, as described above with reference to Figure 5.

There are two approaches to handover UEs to the target eNBs. First, by applying a HO offset between the cells, the“border” of a congested and/or heavily loaded cell can be effectively “moved” to reduce its coverage area. With this approach, the source eNB negotiates with target eNBs for the HO offset settings to avoid handover bouncing (also referred to as“ping-pong”) between source and target cells. The agreed offset will be signalled to the UEs served by the source eNB and no specific set of UEs will be selected in this case.

In a second approach, a source eNB may command HOs to a specific set of UEs towards a selected target eNB (as discussed above. The algorithms for UE/target cell selection are non-standardized (e.g., vendor-proprietary). Besides cell-specific information (e.g., source and target cell load and capacity), these algorithms take into account at least some of the following UE-specific information as input (e.g., depending on availability): radio measurement reports; traffic characteristics (e.g., heavy or light data usage); bearers (e.g., guaranteed bit-rate (GBR) or default); historical and/or current resource utilization; and UE profile (e.g.,“gold”,“silver”,“bronze”).

Of these parameters, the UE radio measurement reports are important to select UEs that have acceptable radio quality in the target eNB. On the other hand, it is also possible to command the HO blindly without the report, assuming that coverage is available. Given other inputs, algorithms with different targets may be developed, e.g. to prioritize heavy users, bronze users, default bear users, etc.

Figure 8 shows an exemplary configuration of a UE measurement model for NR, which was briefly mentioned above. In this model, the UE measures k beams transmitted by a gNB for a particular cell. These k beams correspond to measurements on SSB or C SI RS resources configured for L3 mobility by the network (e.g., gNB) and detected by UE at LI . These beam-specific measurements are labelled“A”, and are typically internal to the PHY. The UE then filters each of these k measurements over time (referred to as“layer- 1 filtering”), resulting in k time-filtered beam measurements labelled“Al”. Neither the measurements themselves (“A”) nor the layer-1 filtering is standardized, i.e., it is typically implementation-dependent. The“Al” measurements are reported to layer 3 (L3), e.g., the RRC layer.

The UE then consolidates these k beam measurements into a cell quality estimate (“B”) based on parameters configured by the network via RRC signalling. The behaviour of the Beam consolidation/selection is standardised. The cell-quality estimate“B” are reported to layer-3 at the same rate as the beam measurements“Al .”

The UE further time-filters the cell quality estimate (referred to as “layer 3 filtering”) resulting in filtered measurement“C” shown in the figure. The behaviour of these layer-3 filters is standardised and the configuration of the layer-3 filters is provided by RRC signalling. Filtering reporting period at“C” equals one measurement period at“B”.

The UE then checks whether actual measurement reporting is necessary at point D. The evaluation can be based on more than one flow of measurements at reference point C, e.g., to compare between different measurements. This is illustrated by inputs C and C¹. The UE evaluates the reporting criteria at least every time a new measurement result is reported at point C, C¹. The reporting criteria are standardised and the configuration is provided from the network by RRC signalling. The value“D” (which can be based on“C”) is reported to the network in an RRC measurement report.

In addition, the time-filtered beam measurements“Al” are further filtered at the RRC layer (“layer 3”) based on a network provided configuration, resulting in filtered beam measurements Έ”. Filtering reporting period at Έ” equals one measurement period at“Al”. The UE selects X beam measurements from these k filtered beam measurements for beam- quality reporting to the network (labelled“F” in the figure). The behaviour of the beam selection is standardised and the configuration is provided by the network by RRC signalling.

Measurement reports can have various characteristics depending on the particular scenario. Measurement reports typically include the measurement identity of the associated measurement configuration that triggered the reporting. As mentioned above, cell and beam measurement quantities to be included in measurement reports are configured by the network. For example, the network can configure beam measurements as beam identifier only, measurement result and beam identifier, or no beam reporting. Furthermore, the number of non-serving cells to be reported can be limited through configuration by the network. In addition, cells belonging to a blacklist configured by the network are not used in event evaluation and reporting; conversely, when a whitelist is configured by the network, only the cells belonging to the whitelist are used in event evaluation and reporting.

Furthermore, neighbour cell measurements can be intra- or inter-frequency with respect to the serving cell. A measurement is defined as an“SSB based intra-frequency measurement” provided that the centre frequency of the SSB of the serving cell and the centre frequency of the SSB of the neighbour cell are the same, and the subcarrier spacing of the two SSBs is also the same. A measurement is defined as an“SSB based inter-frequency measurement” provided that the centre frequency of the SSB of the serving cell and the centre frequency of the SSB of the neighbour cell are different, or the subcarrier spacing of the two SSBs is different.

Similarly, a measurement is defined as a “CSI-RS based intra-frequency measurement” provided that the bandwidth of the CSI-RS resource on the neighbour cell configured for measurement is within the bandwidth of the CSI-RS resource on the serving cell configured for measurement, and the subcarrier spacing of the two CSI-RS resources is the same. A measurement is defined as a“CSI-RS based inter-frequency measurement” provided that the bandwidth of the CSI-RS resource on the neighbour cell configured for measurement is not within the bandwidth of the CSI-RS resource on the serving cell configured for measurement, or the subcarrier spacing of the two CSI-RS resources is different.

In LTE and NR, handovers or PSCell change decisions (e.g., when a UE is operating in any form of dual connectivity, carrier aggregation, etc.) are typically made based on the coverage and quality of a serving cell compared to the quality of a neighbour cell handover candidate. Quality is typically measured in terms of RSRQ or SINR, while coverage is typically measured based on RSRP. In NR, a cell may be comprised by a set of beams where PSS/SSS are transmitted in different downlink beams, each beam associated with a different SSB index. Figure 9 illustrates an exemplary arrangement where a cell includes 65 different downlink beams associated with SSB indices 0-64 respectively.

As discussed above with reference to Figure 8, beam measurement information (SSB/CSI-RS indexes with or without associated measurements) may be included in measurement reports. One of the purposes of these beam reports is to enable a source node to take educated UE mobility decisions to avoid UE ping-pong between serving cells. For example, if multiple neighbor cells are reported (e.g., based on a mobility event where the trigger condition is that the neighbor cell signal becomes better than the source by a certain offset), and these cells have somewhat similar quality/coverage (e.g. similar RSRP and/or RSRQ), beam-quality reports can be used to decide where to handover the UE. For example, network could prioritize the cells with more beams than another cell. Figure 10 shows an exemplary scenario of handover of a UE from a beam of a source cell to one beam of a target cell having 65 total downlink beams.

Recently within 3GPP, a new Study on RAN-centric data collection and utilization for LTE and NR has been approved. As part of that study, the following objectives has been listed, where load balancing is mentioned as one of the features to be studied:

1. Study the use cases and benefits of RAN centric Data utilization, e.g., SON features including mobility optimization (cell and beam based), RACH optimization, load sharing/balancing related optimization, coverage and capacity optimisation, Minimization of Drive testing (MDT), URLLC optimisation, LTE-V2X (i.e., PC5 and uu), etc., applicable to different scenarios in NG-RAN, MR-DC connected to 5GC and EPC and LTE and take NR new features, e.g., beam, network slice, BWP, duplication etc. into account [RAN3, RAN2]

2. Identify necessary standard impact on data collection and utilization for the defined use cases and scenarios, including,

• Definition: Identify relevant measurement quantities, events and faults for collection and utilization. On top of existing RRM measurements and LTE L2 measurements, identify metrics to be newly introduced or to be refined, including [RAN2]:

a. RRM measurement quantities, RLF and access failure information, etc from consenting UEs, b. L2 measurement quantities.

c. LI measurement quantities (e.g. Timing Advance in RAR)

d. Sensor data for UE orientation/altitude to log in addition to location (e.g., digital compass, gyroscope, barometer)

• Collection: Study the procedure for configuration and collection of UE measurements, L1/L2 RAN node measurements and signaling procedure for distributed and central analysis. Identify the potential standard impact on related network entities. Additionally, for MDT study following solutions [RAN3, RAN2]: a. Logged MDT focusing on RRM measurements;

b. Immediate MDT focusing on RRM measurements;

• Utilization: Study necessary procedures and information exchange required for different use cases, e.g. SON, RRM enhancement, edge computing, radio network information exposure, URLLC and LTE-V2X (i.e., PC5 and Uu), etc. [RAN3]

3. If necessary, investigate the benefits and feasibility of introducing a logical entity/function for RAN centric data collection and utilization [RAN3]

As discussed above, the load distribution among the beams of a cell may be non- uniform, and can even vary significantly. Figure 11 shows an exemplary scenario involving a non-uniform distribution of UEs within beams of a cell. In this example, a serving cell is highly loaded at least in an area corresponding to the three beams shown. In addition, a neighbour cell A is highly loaded in two beams but unloaded in two other beams.

A served UE-1 reports measurements (possibly including beam measurements) indicating that a neighbour cell A is detected with good radio condition. UE-1 also reports another neighbour cell B that is more distant than neighbour cell A. The serving node may then request the neighbour cell A to provide its load conditions. According to conventional techniques, the node serving neighbour cell A will indicate a relatively high load in cell A, as at least the same number of UEs and same traffic as in the serving cell itself. This can lead the serving node to conclude that neighbour cell A is overloaded, although cell A has sufficient capacity to accept UE-1 in the beam(s) covering UE-l’s current location. Based on this determination, the serving node may offload UE-1 to neighbour cell B instead, which can result in unacceptable and/or undesirable radio conditions for UE-1.

Exemplary embodiments of the present disclosure address these and other problems, challenges, and/or issues by providing specific enhancements and/or improvements to mobility load balancing (MLB) in wireless communication networks. In general, exemplary embodiments include techniques and/or mechanisms that facilitate MLB between a source node and a target node on a per-beam basis, thereby avoiding and/or overcoming various challenges, problems, and/or drawbacks experienced by conventional per-cell MLB.

According to various embodiments, a source node can request beam-level (e.g. per beam, per beam group, etc.) load-related information (e.g., load and/or capacity) from a target candidate node. Such beam-level load-related information can enable and/or facilitate the source node to take better-informed MLB decisions according to the spatial distribution of load and/or available capacity. In particular, load information from the target node can be provided in a format and/or granularity that is compatible with UE measurements of target node cells and/or beams, so that upon receiving target-node load information and correlating such information with UE measurements, a source is capable of deciding whether particular target node beams are capable to successfully accepting a load-related handover of one or more UEs, including all the services used by these UEs. Put a different way, per-beam target load information allows the source to know whether any available target node capacity is useful for handovers from the source node.

Such beam-level load information can be on different levels of granularity, such as for individual beams, groups of beams, all beams for a particular cell, narrow beams, wide beams, etc. Such beam-level load information can also be correlated with beams transmitting data channels and/or control channels.

In some embodiments, the source node can include in the request at least a target candidate cell for which it wants beam-level load information. For example, the target candidate cell can be a cell reported within an earlier-received UE measurement report that was triggered by the source node.

In some embodiments, the source node can include in the request at least a beam or set (e.g., group) of beams for which it wants beam-level load information. The beam or beam-set can be identified in an earlier-received UE measurement report that included beam measurement information for a particular cell. In various embodiments, the measurement reports can comprise SSB and/or CSI-RS measurements, and the obtained load reports can indicate load on a per-SSB and/or per-CSI-RS basis. Preferably, both the measurement reports and the load reports are related to a particular RS type, e.g., SSB or CSI-RS.

In some embodiments, the source node can request the load information to be reported on an SSB level. In this alternative, each SSB signal is associated with one or more beams within which the SSB is transmitted. The source node may be aware of the SSB signals signaled by a neighbor node cell, e.g., if such information is signaled over an Xn interface to the source node. In these embodiments, the target node can identify the beam coverage area where the SSB signal is broadcast, and can also identify link beams (e.g., data channel beams utilizing data channel resources) serving UEs within this coverage area. In this manner, the target reports load and/or capacity per SSB by providing an indication of the traffic load experienced and/or the available resource capacity in the link beams corresponding to the SSB coverage area.

According to various embodiments, the source node can also obtain the load report from the target candidate node, e.g., according to the request. In a similar manner, the source node can send a load report concerning one or more source beams. This sending and receiving load reports can be referred to as a“load exchange.” In addition, the source node can obtain measurement reports per beam for a cell in a target candidate node, and can correlate this obtained cell and beam measurement information with the per-beam load information obtained from the target node (e.g., via the load report).

According to various embodiments, the source node can also decide to perform a load-triggered handover (i.e., for MLB) from the source node (e.g., from a beam or cell served by the source node) to a target candidate node if it determines that the UE has sufficient coverage in at least a target beam of the target node, for which the load report also indicates sufficient available capacity for the UE at the target node (e.g., associated with the target beam). On the other hand, the source node can decide not to perform such a load-triggered handover from the source node to a target candidate node if it determines that the UE does not have sufficient coverage in a target beam of the target node, and/or the load report indicates there is insufficient available capacity for the UE at the target node (e.g., in any target beams suitable for the UE).

In other embodiments, the load exchange process can be omitted, and instead an overloaded source node triggers a handover request to a target candidate node, in which the source node includes beam measurements (e.g., from one or more UEs served by the source node) for that target node. In this manner, the target node can be made aware of the UE coverage and/or spatial location. In this manner, the target node can determine whether or not the UE(s) is(are) in a coverage area (e.g., of one or more target beams) that is overload. If so, admission control can fail during handover preparation for the UE(s), such that the handover would be rejected. If the UE is not in an overloaded target node coverage area, admission control during handover preparation may be accepted. To facilitate the target node’s admission control determination, the source node can provide additional information for the UE, such as whether and/or how fast the UE is moving, etc. Figure 11 shows a signaling flow of a dedicated procedure for beam-level mobility load balancing (MLB) in a RAN, according to various exemplary embodiments of the present disclosure. Although the exemplary procedure is illustrated in Figure 11 by specific operations in a particular order, the operations can be performed in different orders than shown and can be combined and/or divided into blocks and/or operations having different functionality than shown. Furthermore, the exemplary procedure shown in Figure 11 can be complementary to other exemplary procedures disclosed herein, such that they are capable of being used cooperatively to provide the benefits, advantages, and/or solutions to problems described herein.

As shown in Figure 12, a source node 1220 and a target node 1230 engage in a signaling procedure to trigger load reporting from one of the nodes. As an example, the first node is a serving (or source) node, serving a UE that could potentially handover to a different RAN node. The second node is a target node, e.g., a node selected as a potential mobility target for the UE. In the exemplary scenario shown in Figure 12, the source node requests the target node to setup load reporting signaling.

Prior to the operations shown in Figure 12, a UE served by the source node may have been configured to report measurements made on beams associated with one or more neighbor cells, including beams associated with the target node shown. The UE reports such measurements to the source node (operation labelled“0” in Figure 12). These measurements can be reported, e.g., together with measurements made on one or more beams transmitted by the source node (also referred to as“source beams”).

The source node can then initiate a Resource Information Request (“1”) to the target node for beam-level load-related information. In this operation, the source node can request a single resource information report pertaining to one or more beam of the target node (which can be indicated in the request), or it can request periodic reporting by also specifying a reporting period. In various embodiments, the requested“resource information report” can be a report comprising information about experienced traffic load, available traffic capacity, overload or congestion, etc. More generally, a resource information report can include any load-related information that helps the receiving node to better understand the availability of beam-specific radio resources at the sending node.

The source node can also indicate, in the Resource Information Request, a specific beam or set of beams transmitted by the target node for which beam -level information (i.e., beam-specific or beam-group-specific information) is requested. For instance, such beams could have been selected by the source node based on the received UE measurement reports (e.g., in operation“0”). As such, the request for beam-level information may include an identifier for each beam or group of beams for which the target candidate node is requested to report beam-level information. A group of beams could be specified, for instance, as a list of narrow beams, or as a combination of narrow beams into a wider beam.

By enabling the source node to request beam-specific or beam-group specific information from the target node in this manner, exemplary embodiments reduce and/or minimize the amount of data to be reported by the target node, thereby reducing the computational costs for the target node as well as the traffic load over the node-to-node interface (e.g., X2 or Xn interface). Exemplary embodiments provide the further advantage of providing the source node with an increased spatial resolution (e.g., smaller spatial granularity) of the load, resource utilization, and/or capacity in the target node.

In some embodiments, the source node can specify, in the request to the target node, a granularity, resolution, and/or type of resource information being requested. For example, the source node can specify that the requested resource information report is for one or more of the following load types (including combinations thereof):

• Per SSB: The source node can rely on its knowledge of SSB signals transmitted in one or more cells of the target node. Upon receiving a request for resource information report per SSB, the target node can determine the coverage area of the SSB(s) for which reports are requested. This can be done, for example, by considering coverage areas of beams within which the requested SSB is transmitted; data channels and data-channel resources used in such SSB coverage area (e.g., all data channels active in the data channel beams within the SSB coverage area). In this manner, the target node can determine radio resources available for data channel communication within the SSB coverage area.

• Per CSI-RS: The source node can rely on its knowledge of CSI-RS signals transmitted in one or more cells of the target node. Upon receiving a request for resource information report per CSI-RS, the target node can determine the coverage area of the CSI-RS(s) for which reports are requested. This can be done, for example, by considering the coverage of beams within which the CSI-RS is transmitted; data channels and data-channel resources used in such CSI-RS coverage area (e.g., all data channels active in the data channel beams within the CSI-RS coverage area). In this manner, the target node can determine radio resources available for data channel communication within the CSI-RS coverage area. • Per link beam: The source node can rely on its knowledge of link beam signals transmitted in one or more cells of the target node. Upon receiving a request for resource information report per link beam, the target node can determine the coverage area of the link beam(s) for which reports are requested. This can be done, for example, by considering the coverage area of the individual link beams; data channels and data-channel resources used in such link beam coverage area (e.g., all data channels active within the link beam coverage area). In this manner, the target node can determine radio resources available for data channel communication within the link beam coverage area.

• Per Bandwidth Part (BWP): The source node can rely on its knowledge of BWPs in one or more cells of the target node. Upon receiving a request for resource information report per BWP, the target node needs to consider all the data channels and the resources used by them in such BWP. In this manner, the target node can determine radio resources available for data channel communication within the BWP.

• Per slice or type of traffic: the source RAN may further specify a type of traffic or a network slice for which resource information shall be reported by the target RAN network node. This has the advantage of enabling MLB functionalities dedicated to a particular type of traffic, e.g., URLLC, MBB, etc, or dedicated to specific network slices.

If the target node is able to configure measurement of resource information as requested by the source node, the target node can respond with a Resource Information Response (“2”) acknowledging that Resource Information Updates will be sent as requested by the source node. Subsequently, after the target node is determines the resource information as requested by the source node (e.g., according to the requested granularlity, resolution, and/or type), the target node can send a resource information report (“3”) to the source node.

After receiving the resource information report (“3”), the source node can also receive one or more further measurement reports from UEs that it serves (“4”). For example, these measurement reports can include measurements on the same source and target beams as previously measured and/or reported (e.g., in“0”). In any event, such measurements can be useful in MLB operations between source beams and target beams, e.g., of the target node. Subsequently, the source node can perform a MLB operation with respect to the target node (“5”). This can include selecting one or more target beams handover of one or more UEs served by one or more source beams. This selection can be based on the UE measurements reported earlier (e.g., in“0” and/or“4”), as well as the beam-level load information reported from the target node (e.g., in“3”), as well as the source node’s own beam-level load information (e.g., of source beam).

In this manner, the source node is able to decide the best handover target for the UE. It should be noted that during the handover procedure the source node can provide to the target node an indication of the coverage area or radio resources where the UE should be handed over, such indication being derived from received load information. For example, the source node could indicate to the target node in the handover preparation procedure that the UE should be handed over to a specific SSB. This should be interpreted by the target node as to indicate that the UE should be handed over to the data channel beams covering the specific SSB coverage area.

Various exemplary embodiments can also be used in a 5G network in which each RAN node (e.g., gNB) has functionality split between a central unit (CU) and one or more distributed units (DUs), such as shown in Figure 4. In such embodiments, the functionality of the Resource Information Request/Response/Update procedures discussed above can also be distributed among DU and CU.

In such embodiments, requested resource information can be generated by a gNB- DU, which is aware of the resources utilized (and available) according to the requested granularity, resolution, and/or type, e.g., per SSB, per CSI-RS, etc. Within the split architecture, a source gNB-CU can trigger a Resource Information Request towards a neighbor node (e.g., gNB-CU) without engaging in signaling with its directly connected gNB-DUs. The target gNB-CU receiving the Resource Information Request would then forward the request to the gNB-DU serving the beams, reference signals, and/or network slices to which the request applies. The target gNB-DU can evaluate whether the requested load information can be provided, and reply to the target gNB-CU with a response (positive) or a failure (negative). This is similar to the response in the non-split architecture discussed above; however, the target gNB-CU receiving a Resource Information Response/Failure from the target gNB-DU also forwards it to the source gNB-CU that originated the request.

After the Resource Information Request/Response have been concluded, the gNB- DU would have to generate the Resource Information Update and signal it to its connected gNB-CU. The gNB-CU would have to forward the Resource Information update to the source node that requested the update in the first place. It needs to be noted that the content of the messages exchanged between gNB-CU and gNB-DU may be identical to the content of the messages exchanged between source and target nodes. However, differences in such messages may exist.

In general, a gNB-CU can split, parse, merge, and/or aggregate messages to and from the gNB DUs related to resource information reporting and configuration. In this manner, communication between gNB-CUs or between RAN nodes can occur via interfaces such as the X2 or Xn, while communication between gNB-CU and gNB-DU may occur via interfaces such as the F 1.

For example, the target gNB-CU may aggregate multiple Resource Information Requests from different neighbor nodes that pertain to the same gNB-DU, and send them in one message to that gNB-DU. Similarly, the target gNB-CU may split a Resource Information Request received from a source node (e.g., another gNB/gNB-CU or a gNB- DU associated with the target gNB-CU) into requests towards different gNB-DUs, each of which may be responsible for a subset of the target beams identified in the request.

Similarly, a target gNB-CU can aggregate Resource Information Update messages from different gNB-DUs into one Resource information update towards the source node that requested the update. This could happen in cases where the beams, coverage areas, slices - or in general, the entities for which the load reporting has been requested - are distributed across several gNB-DUs. In such case, the gNBN-CU can aggregate the load information sent by each gNB-DU for each entity (per SSB, CSI-RS, etc.), and signal the overall resource information to the source node that requested it.

In some embodiments, the Resource Information Request (“1”) can include specify a type of resource information to be reported, such as traffic load information, resource utilization, resource availability, capacity, etc. The type of resource information requested by the source node to be reported can be the same for all beams or groups of beams or different for different beams or groups of beams.

In some embodiments, reported beam-level load information can identify a number of users (e.g., in RRC CONNECTED, RRC IDLE, or both) being present in the coverage area of a beam or group of beams. For example, when the group of beams comprises all beams, the load information can identify the number of users (e.g., in RRC CONNECTED, RRC IDLE, or both) present in the entire cell. In some embodiments, beam -level load information can identify UE time-frequency resource utilization within the coverage area of a beam or group of beams. Such resource utilization can be expressed for different granularity, such as per resource block (RB), per resource block group (RBG), for the entire frequency spectrum (i.e., wideband), or per BWP.

In some embodiments, the source node may further specify a type of traffic or a network slice for which beam-level information should be reported by the target candidate network node. Reporting of this beam- and traffic/slice-specific load-related information can facilitate MLB operations in the source node that are focused on a particular type of traffic (e.g., URLLC, MBB, etc.) or on specific network slices.

As mentioned above, in some embodiments, the Resource Information Request (“1”) can include a requested periodicity (e.g., frequency) of the requested beam-level information report. This periodicity can be selected, adapted, and/or determined based on user mobility or traffic patterns in the source cell and/or the target cell, so as to improve mobility load balancing and handover procedures.

Upon receiving the Resource Information Request, the target node can configure UE measurements within its coverage area based on the contents of this request from the source node. For example, beam-level load information can be determined by the target node based on UE measurement reports associated to downlink radio beams transmitted by the target node and measured by UEs served by the target node (e.g., via SSB and CSI-RS). The load of a beam may be expressed, for instance, in terms of UEs present in the coverage area of the beam. In such case, the target node can consider a particular UE as present in the coverage area of the beam for which the UE reports the highest signal strength. In this manner, the target node can determine the distribution of UEs that it serves within the respective beams that the target node transmits.

In some embodiments, the target node can combine and/or correlate UE-to-beam association information (determined, e.g., based on signal strength measurements per beam) with layer-2 (L2) scheduling decisions for different RBs in different transmission time intervals (TTIs). In this manner, the target node can determine a distribution of load for a beam or a group of beams not only spatially, but also over time and/or frequency.

In some embodiments, the target node can combine and/or correlate the UE-to-beam association information with the type of traffic requested by the UEs associated with the beam. In this manner, the target node can determine a spatial distribution of different traffic types on a per-beam or a per-beam-group within the overall coverage area of the target node.

In some embodiments, the target node can combine and/or correlate the UE-to-beam association information with mobility reports so as to determine a spatial distribution of mobility patterns for a beam or a group of beams. In this manner, the target node can identify coverage areas (e.g., beams or beam groups) with high-mobility UEs and/or coverage areas with low-mobility UEs within the overall coverage area of the target node.

In some embodiments, the target node can combine and/or correlate the UE-to-beam association information with the network slices used by the UEs associated with the beam. In this manner, the target node can determine a spatial distribution of different network slices on a per-beam or a per-beam-group within the coverage area of the target node.

The following is exemplary text specifying resource information reporting functionality that is suitable for inclusion in a 3GPP specification, such as 3GPP TS 36.423 that specifies the X2-AP interface between eNBs in an LTE RAN (or between gNBs that support the X2 interface). Nevertheless, skilled persons will readily comprehend that, with suitable modifications, such text could also be included in other 3GPP specifications, such as for the Xn interface between gNBs in an NG-RAN.

*** Begin proposed 3GPP specification text ***

8.3.6 Resource Information Reporting Initiation

8.3.6.1 General

This procedure is used by an gNB to request the reporting of load measurements to another gNB, which may include load measurements per beam.

8.3.6.2 Successful Operation Figure 13 is a signalling flow diagram illustrating successful initiation of resource status reporting between two network nodes (e.g., gNBs). The procedure is initiated with a RESOURCE INFORMATION REQUEST message sent from gNBi to gNB2. Upon receipt, gNB₂:

- shall initiate the requested measurement according to the parameters given in the request in case the message includes an indication to "start"; or

- shall stop all cells and beams measurements and terminate the reporting in case the message includes an indication to "stop"; or

- if supported, stop measurements and terminate the reporting for indicated cells or beams or reference signals, in case the message includes an indication set to "partial stop"; or - if supported, add cells or beams or reference signals to the measurements initiated in a previous Resource Information Request, in case the message includes an indication set to "add".

If the Resource Information Request message includes an indication to "start" the Resource Information reporting, then an indication on the characteristics of the resource information report, e.g. resource granularity, shall be included in RESOURCE INFORMATION REQUEST message.

If the RESOURCE INFORMATION REQUEST message includes an indication of periodic Resource Information Reporting together with a reporting period, eNE shall use its value as the time interval between two subsequent RESOURCE INFORMATION UPDATE messages that include the requested resource information.

If eNB2 is capable to provide all requested resource information, it shall initiate the measurement as requested by eNBi, and respond with the RESOURCE INFORMATION RESPONSE message. If eNB2 is capable to provide some but not all of the requested resource information and an indication of partial success is present in the RESOURCE INFORMATION REQUEST message, it shall initiate the measurement for the admitted measurement objects.

8.3.7 Resource Status Reporting

8.3.7.1 General This procedure is initiated by eNE to report the result of measurements admitted by eNE following a successful Resource Information Reporting Initiation procedure.

8.3.7.2 Successful Operation

Figure 14 is a signalling flow diagram illustrating successful resource status reporting between two LTE network nodes (e.g., eNBs). The eNE shall report the results of the admitted measurements in RESOURCE INFORMATION UPDATE message. The admitted measurements are the measurements that were successfully initiated during the preceding Resource Information Reporting Initiation procedure.

If the eNBi receives the RESOURCE Information UPDATE message, which includes an indication to stop reporting for one or more cells or beams . the eNBi should initialise the Resource Information Reporting Initiation procedure (see 8.3.6 above) to remove all or some of the corresponding cells or beams from the measurement.

*** End proposed 3 GPP specification text ***

Figure 15 illustrates an exemplary tabular encoding for the resource information reported between two network nodes, such as shown in Figure 14. In particular, this figure illustrates the exemplary embodiments of reporting resources available per SSB. In some embodiments, the Available Resources IE can be expressed relative to a cell class. In other words, the value may be associated with another value that identifies the type of cell for which available resources are calculated. As an example, the cell may be deployed over low bands or high bands, or it might have a variable total bandwidth. Since the Available Resource value is an index on a linear scale, the cell class is used as an index to identify the full capacity of the referenced cell in absolute terms. In this manner, it is possible to identify the capacity in terms of resources indicated by the Available Resources IE.

These embodiments described above can be further illustrated with reference to Figures 16-17, which depict exemplary methods (e.g., procedures) performed by a source node and a target node, respectively. In other words, various features of the operations described below, with reference to Figures 16-17, correspond to various embodiments described above.

In particular, Figure 16 illustrates an exemplary method (e.g., procedure) for beam- level mobility load balancing (MLB) in a radio access network (RAN), according to various exemplary embodiments of the present disclosure. The exemplary method can be performed by a source node (e.g., base station, eNB, gNB, etc. or component thereof, such as a gNB-CU or gNB-DU) in the RAN, serving one or more user equipment (UEs, e.g., wireless devices, MTC devices, NB-IoT devices, modems, etc. or components thereof) with one or more beams and/or cells, such as illustrated in other figures described herein. Although the exemplary method is illustrated in Figure 16 by specific blocks in a particular order, the operations corresponding to the blocks can be performed in different orders than shown and can be combined and/or divided into blocks having different functionality than shown. Furthermore, the exemplary method shown in Figure 16 can be complementary to other exemplary methods disclosed herein (e.g., Figure 17), such that they can be used cooperatively to provide the benefits, advantages, and/or solutions to problems described herein. Optional blocks and/or operations are indicated by dashed lines. In some embodiments, the exemplary method can include the operations of block 1610, where the source node can receive one or more measurement reports from a plurality of UEs. Each measurement report can include radio measurements related to a source beam or a source cell associated with the source node and/or one or more target beams associated with one or more target nodes in the RAN.

In some embodiments, the source node can have a split CU-DU architecture. In such embodiments, the exemplary method can include the operations of blocks 1620-1630, which can be performed by the source node CU. In block 1620, the source node can receive resource requests from one or more distributed units (DUs) associated with the CU. In block 1630, the source node can aggregate the resource requests into a resource information request for the target node (e.g., sent to the target node in block 1640, described below).

The exemplary method can also include the operations of block 1640, where the source node can send a resource information request, to a target node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN. The resource information request can identify at least one of the following: one or more first types of requested resource information; and one or more second types of resource granularity for which resource information is requested. In some embodiments, the resource information request can be based on the received measurement reports from the UEs (e.g., received in block 1610).

• traffic load information,

• utilization of time-frequency resources,

• available capacity,

• number of user equipment (UEs), and

• number of UEs in RRC CONNECTED mode.

• per SS/PBCH block (SSB) beam,

• per channel state information reference signal (CSI-RS) beam,

• per link beam,

• per bandwidth part (BWP),

• per network slice, and • per traffic type.

In some embodiments, the resource information request can also identify one or more of the following for which resource information is requested: one or more specific beams or specific groups of beams associated with the target node; one or more cells associated with the specific beams or specific groups of beams; one or more of the first types; one or more specific types of traffic; and one or more specific network slices. In some embodiments, the resource information request can also identify a frequency or periodicity and/or timing of resource information reports (e.g., from the target node in response to the request). In some embodiments, the exemplary method can include the operations of block 1650, where the source node can receive, from the target node, a response acknowledging that resource information reports will be sent as requested by the source node.

The exemplary method can also include the operations of block 1660, where the source node can receive one or more resource information reports, from the target node, including resource information according to at least one of the first types (i.e., of requested resource information) and/or at least one of the second types (i.e., of resource granularity) identified in the resource information request. In some embodiments, the resource information in each resource information report can include one or more of the following:

• available capacity in a cell for one or more specific network slices; and

specific groups of SSB beams associated with the target node.

In embodiments where the source node has a split CU-DU architecture, the exemplary method can include the operations of blocks 1670-1680, which can be performed by the source node CU. For example, blocks 1670-1680 can be performed together with blocks 1620-1630, discussed above. In block 1670, the source node can split each of the resource information reports (e.g., received from the target node in block 1660) into a plurality of further resource information reports, each further resource information report associated with a different one of the DUs. In block 1680, the source node can send the further resource information reports to the respective DUs. In some embodiments, the target node can be a further CU (e.g., part of a different gNB than the source node) or a further DU associated with the CU of the source node (e.g., part of the same gNB as the source node). In some embodiments, the exemplary method can also include the operations of block 1690, where the source node can select at least one of the target beams for handover of a subset of the first plurality of UEs from the source beam. This selection can be based on the the resource information reports (e.g., received in block 1660) and, in some embodiments, the UE measurement reports (e.g., received in block 1610).

In some embodiments, the exemplary method can also include the operations of block 1695, where the source node can perform a handover procedure with the target node with respect to the subset of UEs. In some embodiments, the operations of block 1695 can include the operations of sub-block 1696, where the source node can send, to the target node, an indication that a particular UE, of the subset of UEs, should be handed over to the selected target beams. In such embodiments, the selected target beams are respective SSBs having respective SSB coverage areas and associated with respective SSB indices. Furthermore, the indication includes the respective SSB indices and indicates that the particular UE should be handed over to respective link beams having coverage areas overlapping with the SSB coverage areas. In the case where the subset of UEs includes a plurality of UEs, the source node can repeat the operations of block 1696 for each of the UEs individually.

In addition, Figure 17 illustrates another exemplary method (e.g., procedure) for beam-level mobility load balancing (MLB) in a radio access network (RAN), according to various exemplary embodiments of the present disclosure. The exemplary method shown in Figure 17 can be performed by a target node e.g., base station, eNB, gNB, etc. or component thereof, such as a gNB-CU or gNB-DU) in the RAN that utilizes beams to communicate with UEs, such as illustrated in other figures described herein. Although the exemplary method is illustrated in Figure 17 by specific blocks in a particular order, the operations corresponding to the blocks can be performed in different orders than shown and can be combined and/or divided into blocks having different functionality than shown. Furthermore, the exemplary method shown in Figure 17 can be complementary to other exemplary methods disclosed herein (e.g., Figure 16), such that they can be used cooperatively to provide the benefits, advantages, and/or solutions to problems described herein. Optional blocks and/or operations are indicated by dashed lines.

The exemplary method can include the operations of block 1710, where the target node can receive a resource information request, from a source node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN. The resource information request can identify at least one of the following: one or more first types of requested resource information; and one or more second types of resource granularity for which resource information is requested.

• traffic load information,

• utilization of time-frequency resources,

• available capacity,

• number of user equipment (UEs), and

• number of UEs in RRC CONNECTED mode.

• per SS/PBCH block (SSB) beam,

• per channel state information reference signal (CSI-RS) beam,

• per link beam,

• per bandwidth part (BWP),

• per network slice, and

• per traffic type.

In some embodiments, the resource information request can also identify one or more of the following for which resource information is requested: one or more specific beams or specific groups of beams associated with the target node; one or more cells associated with the specific beams or specific groups of beams; one or more of the first types; one or more specific types of traffic; and one or more specific network slices. In some embodiments, the resource information request can also identify a frequency or periodicity and/or timing of resource information reports (e.g., to the source node in response to the request). In some embodiments, the exemplary method can include the operations of block 1720, where the target node can send, to the source node, a response acknowledging that resource information reports will be sent as requested by the source node.

In some embodiments, the response also indicates at least one of the following that can be, or will be, included in the resource information reports: one or more first types of resource information, and one or more second types of resource granularity for the resource information. For example, the one or more first types and/or one or more second types indicated in the response can be different from the one or more first types and/or one or more second types indicated in the resource information request (e.g., received in block 1710). In some embodiments, the exemplary method can include the operations of blocks 1730-1750. In block 1730, the target node can configure measurements by a second plurality of UEs based on the resource information request from the source node. In block 1740, the target node can receive measurement reports from the second plurality of UEs in response to the configured measurements. Each measurement report can include radio measurements related to a plurality of target beams associated with the target node. In block 1750, the target node can determine resource information, to be included in the resource information reports, based on the measurement reports.

In some embodiments, each measurement report can include signal strengths for the plurality of target beams. In such embodiments, the operations of block 1750 can include the operations of block 1751, where the target node can, for each particular UE of the second plurality of UEs, associate the particular UE with the target beam for which the particular UE reports the highest signal strength. In some of these embodiments, the operations of block 1750 can also include the operations of block 1752, where the target node can correlate the particular UE’s associated target beam with resources scheduled by the target node for the particular UE and/or a traffic type requested by the particular UE.

In some embodiments, the target node can have a split CU-DU architecture. In such embodiments, the operations of block 1750 can include the operations of sub-blocks 1753- 1756, which can be performed by a central unit (CU) of the target node. In sub-block 1753, the target node can split the resource information request into a plurality of further resource information requests for a respective plurality of distributed units (DUs) associated with the CU. In sub-blocks 1754-1755, the target node can send the further resource information requests to the respective DUs, and receive a plurality of responses for the respective DUs. In sub-block 1756, the target node can aggregate the plurality of responses into resource information, e.g., to be included in resource information reports sent to the source node in block 1760, discussed below. In some embodiments, the source node can be a further CU (e.g., part of a different gNB than the target node) or a further DU associated with the CU of the target node (e.g., part of the same gNB as the target node).

The exemplary method can also include the operations of block 1760, where the target node can send one or more resource information reports, to the source node, including resource information according to at least one of the first types (i.e., of requested resource information) and/or at least one of the second types (i.e., of resource granularity) identified in the resource information request. In some embodiments, the resource information in each resource information report can include one or more of the following: • available capacity for one or more specific SSB beams or specific groups of SSB beams associated with the target node;

• available capacity in a cell for one or more specific network slices; and

specific groups of SSB beams associated with the target node.

In some embodiments, the exemplary method can also include the operations of block 1770, where the target node can perform a handover procedure with the source node with respect to one or more UEs served by a source beam associated with the source node. In some embodiments, the operations of block 1770 can include the operations of sub-block 1772, where the target node can receive, from the source node, an indication that a particular one of the UEs should be handed over to at least one of the target beams associated with the target node. In such embodiments, the at least one target beams are respective SSBs having respective SSB coverage areas and associated with respective SSB indices. Furthermore, the indication includes the respective SSB indices and indicates that the particular UE should be handed over to respective link beams having coverage areas overlapping with the SSB coverage areas. In the case where the one or more UEs includes a plurality of UEs, the target node can repeat the operations of block 1772 for each of the UEs individually.

Although the subject matter described herein can be implemented in any appropriate type of system using any suitable components, the embodiments disclosed herein are described in relation to a wireless network, such as the example wireless network illustrated in Figure 18. For simplicity, the wireless network of Figure 18 only depicts network 1806, network nodes 1860 and 1860b, and WDs 1810, 1810b, and 1810c. In practice, a wireless network can include any additional elements suitable to support communication between wireless devices or between a wireless device and another communication device, such as a landline telephone, a service provider, or any other network node or end device. Of the illustrated components, network node 1860 and wireless device (WD) 1810 are depicted with additional detail. The wireless network can provide communication and other types of services to one or more wireless devices to facilitate the wireless devices’ access to and/or use of the services provided by, or via, the wireless network.

The wireless network can comprise and/or interface with any type of communication, telecommunication, data, cellular, and/or radio network or other similar type of system. In some embodiments, the wireless network can be configured to operate according to specific standards or other types of predefined rules or procedures. Thus, particular embodiments of the wireless network can implement communication standards, such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, or 5G standards; wireless local area network (WLAN) standards, such as the IEEE 802.11 standards; and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave and/or ZigBee standards.

Network 1806 can comprise one or more backhaul networks, core networks, IP networks, public switched telephone networks (PSTNs), packet data networks, optical networks, wide-area networks (WANs), local area networks (LANs), wireless local area networks (WLANs), wired networks, wireless networks, metropolitan area networks, and other networks to enable communication between devices.

Network node 1860 and WD 1810 comprise various components described in more detail below. These components work together in order to provide network node and/or wireless device functionality, such as providing wireless connections in a wireless network. In different embodiments, the wireless network can comprise any number of wired or wireless networks, network nodes, base stations, controllers, wireless devices, relay stations, and/or any other components or systems that can facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.

As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a wireless device and/or with other network nodes or equipment in the wireless network to enable and/or provide wireless access to the wireless device and/or to perform other functions ( e.g ., administration) in the wireless network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g, radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)). Base stations can be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and can then also be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station can be a relay node or a relay donor node controlling a relay. A network node can also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station can also be referred to as nodes in a distributed antenna system (DAS).

Further examples of network nodes include multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), core network nodes ( e.g ., MSCs, MMEs), O&M nodes, OSS nodes, SON nodes, positioning nodes (e.g., E-SMLCs), and/or MDTs. As another example, a network node can be a virtual network node as described in more detail below. More generally, however, network nodes can represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a wireless device with access to the wireless network or to provide some service to a wireless device that has accessed the wireless network.

In Figure 18, network node 1860 includes processing circuitry 1870, device readable medium 1880, interface 1890, auxiliary equipment 1884, power source 1886, power circuitry 1887, and antenna 1862. Although network node 1860 illustrated in the example wireless network of Figure 18 can represent a device that includes the illustrated combination of hardware components, other embodiments can comprise network nodes with different combinations of components. It is to be understood that a network node comprises any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods and/or procedures disclosed herein. Moreover, while the components of network node 1860 are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, a network node can comprise multiple different physical components that make up a single illustrated component (e.g, device readable medium 1880 can comprise multiple separate hard drives as well as multiple RAM modules).

Similarly, network node 1860 can be composed of multiple physically separate components (e.g, a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which can each have their own respective components. In certain scenarios in which network node 1860 comprises multiple separate components (e.g, BTS and BSC components), one or more of the separate components can be shared among several network nodes. For example, a single RNC can control multiple NodeB’s. In such a scenario, each unique NodeB and RNC pair, can in some instances be considered a single separate network node. In some embodiments, network node 1860 can be configured to support multiple radio access technologies (RATs). In such embodiments, some components can be duplicated (e.g, separate device readable medium 1880 for the different RATs) and some components can be reused ( e.g . , the same antenna 1862 can be shared by the RATs). Network node 1860 can also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1860, such as, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wireless technologies. These wireless technologies can be integrated into the same or different chip or set of chips and other components within network node 1860.

Processing circuitry 1870 can be configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being provided by a network node. These operations performed by processing circuitry 1870 can include processing information obtained by processing circuitry 1870 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Processing circuitry 1870 can comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 1860 components, such as device readable medium 1880, network node 1860 functionality. Such functionality can include providing any of the various wireless features, functions, or benefits discussed herein.

For example, processing circuitry 1870 can execute instructions stored in device readable medium 1880 or in memory within processing circuitry 1870. In some embodiments, processing circuitry 1870 can include a system on a chip (SOC). As a more specific example, instructions (also referred to as a computer program product) stored in medium 1880 can include instructions that, when executed by processing circuitry 1870, can configure network node 1860 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein.

In some embodiments, processing circuitry 1870 can include one or more of radio frequency (RF) transceiver circuitry 1872 and baseband processing circuitry 1874. In some embodiments, radio frequency (RF) transceiver circuitry 1872 and baseband processing circuitry 1874 can be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 1872 and baseband processing circuitry 1874 can be on the same chip or set of chips, boards, or units

In certain embodiments, some or all of the functionality described herein as being provided by a network node, base station, eNB or other such network device can be performed by processing circuitry 1870 executing instructions stored on device readable medium 1880 or memory within processing circuitry 1870. In alternative embodiments, some or all of the functionality can be provided by processing circuitry 1870 without executing instructions stored on a separate or discrete device readable medium, such as in a hard-wired manner. In any of those embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 1870 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 1870 alone or to other components of network node 1860, but are enjoyed by network node 1860 as a whole, and/or by end users and the wireless network generally.

Device readable medium 1880 can comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that can be used by processing circuitry 1870. Device readable medium 1880 can store any suitable instructions, data or information, including a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 1870 and, utilized by network node 1860. Device readable medium 1880 can be used to store any calculations made by processing circuitry 1870 and/or any data received via interface 1890. In some embodiments, processing circuitry 1870 and device readable medium 1880 can be considered to be integrated.

Interface 1890 is used in the wired or wireless communication of signalling and/or data between network node 1860, network 1806, and/or WDs 1810. As illustrated, interface 1890 comprises port(s)/terminal(s) 1894 to send and receive data, for example to and from network 1806 over a wired connection. Interface 1890 also includes radio front end circuitry 1892 that can be coupled to, or in certain embodiments a part of, antenna 1862. Radio front end circuitry 1892 comprises filters 1898 and amplifiers 1896. Radio front end circuitry 1892 can be connected to antenna 1862 and processing circuitry 1870. Radio front end circuitry can be configured to condition signals communicated between antenna 1862 and processing circuitry 1870. Radio front end circuitry 1892 can receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 1892 can convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1898 and/or amplifiers 1896. The radio signal can then be transmitted via antenna 1862. Similarly, when receiving data, antenna 1862 can collect radio signals which are then converted into digital data by radio front end circuitry 1892. The digital data can be passed to processing circuitry 1870. In other embodiments, the interface can comprise different components and/or different combinations of components.

In certain alternative embodiments, network node 1860 may not include separate radio front end circuitry 1892, instead, processing circuitry 1870 can comprise radio front end circuitry and can be connected to antenna 1862 without separate radio front end circuitry 1892. Similarly, in some embodiments, all or some of RF transceiver circuitry 1872 can be considered a part of interface 1890. In still other embodiments, interface 1890 can include one or more ports or terminals 1894, radio front end circuitry 1892, and RF transceiver circuitry 1872, as part of a radio unit (not shown), and interface 1890 can communicate with baseband processing circuitry 1874, which is part of a digital unit (not shown).

Antenna 1862 can include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. Antenna 1862 can be coupled to radio front end circuitry 1890 and can be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In some embodiments, antenna 1862 can comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between, for example, 2 GHz and 66 GHz. An omni-directional antenna can be used to transmit/receive radio signals in any direction, a sector antenna can be used to transmit/receive radio signals from devices within a particular area, and a panel antenna can be a line of sight antenna used to transmit/receive radio signals in a relatively straight line. In some instances, the use of more than one antenna can be referred to as MIMO. In certain embodiments, antenna 1862 can be separate from network node 1860 and can be connectable to network node 1860 through an interface or port.

Antenna 1862, interface 1890, and/or processing circuitry 1870 can be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by a network node. Any information, data and/or signals can be received from a wireless device, another network node and/or any other network equipment. Similarly, antenna 1862, interface 1890, and/or processing circuitry 1870 can be configured to perform any transmitting operations described herein as being performed by a network node. Any information, data and/or signals can be transmitted to a wireless device, another network node and/or any other network equipment.

Power circuitry 1887 can comprise, or be coupled to, power management circuitry and can be configured to supply the components of network node 1860 with power for performing the functionality described herein. Power circuitry 1887 can receive power from power source 1886. Power source 1886 and/or power circuitry 1887 can be configured to provide power to the various components of network node 1860 in a form suitable for the respective components ( e.g ., at a voltage and current level needed for each respective component). Power source 1886 can either be included in, or external to, power circuitry 1887 and/or network node 1860. For example, network node 1860 can be connectable to an external power source (e.g., an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry 1887. As a further example, power source 1886 can comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry 1887. The battery can provide backup power should the external power source fail. Other types of power sources, such as photovoltaic devices, can also be used.

Alternative embodiments of network node 1860 can include additional components beyond those shown in Figure 18 that can be responsible for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, network node 1860 can include user interface equipment to allow and/or facilitate input of information into network node 1860 and to allow and/or facilitate output of information from network node 1860. This can allow and/or facilitate a user to perform diagnostic, maintenance, repair, and other administrative functions for network node 1860.

In some embodiments, a WD (e.g., WD 2010) can be configured to transmit and/or receive information without direct human interaction. For instance, a WD can be designed to transmit information to a network on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the network. Examples of a WD include, but are not limited to, smart phones, mobile phones, cell phones, voice over IP (VoIP) phones, wireless local loop (WLL) phones, desktop computers, personal digital assistants (PDAs), wireless cameras, gaming consoles or devices, music storage devices, playback appliances, wearable terminal devices (e.g., smart watches), wireless endpoints, mobile stations, tablets, laptops, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart devices, wireless customer-premise equipment (CPE), vehicle-mounted wireless terminal devices, etc.

A WD can support device-to-device (D2D) communication, for example by implementing a 3 GPP standard for sidelink communication, vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-everything (V2X) and can in this case be referred to as a D2D communication device. As yet another specific example, in an Internet of Things (IoT) scenario, a WD can represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another WD and/or a network node. The WD can in this case be a machine-to-machine (M2M) device, which can in a 3GPP context be referred to as an MTC device. As one particular example, the WD can be a UE implementing the 3 GPP narrow band internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances ( e.g ., refrigerators, televisions, etc.) personal wearables (e.g., watches, fitness trackers, etc.). In other scenarios, a WD can represent a vehicle or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. A WD as described above can represent the endpoint of a wireless connection, in which case the device can be referred to as a wireless terminal. Furthermore, a WD as described above can be mobile, in which case it can also be referred to as a mobile device or a mobile terminal.

As illustrated, wireless device 1810 includes antenna 1811, interface 1814, processing circuitry 1820, device readable medium 1830, user interface equipment 1832, auxiliary equipment 1834, power source 1836 and power circuitry 1837. WD 1810 can include multiple sets of one or more of the illustrated components for different wireless technologies supported by WD 1810, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, or Bluetooth wireless technologies, just to mention a few. These wireless technologies can be integrated into the same or different chips or set of chips as other components within WD 1810.

Antenna 1811 can include one or more antennas or antenna arrays, configured to send and/or receive wireless signals, and is connected to interface 1814. In certain alternative embodiments, antenna 1811 can be separate from WD 1810 and be connectable to WD 1810 through an interface or port. Antenna 1811, interface 1814, and/or processing circuitry 1820 can be configured to perform any receiving or transmitting operations described herein as being performed by a WD. Any information, data and/or signals can be received from a network node and/or another WD. In some embodiments, radio front end circuitry and/or antenna 1811 can be considered an interface.

As illustrated, interface 1814 comprises radio front end circuitry 1812 and antenna 1811. Radio front end circuitry 1812 comprise one or more filters 1818 and amplifiers 1816. Radio front end circuitry 1814 is connected to antenna 1811 and processing circuitry 1820, and can be configured to condition signals communicated between antenna 1811 and processing circuitry 1820. Radio front end circuitry 1812 can be coupled to or a part of antenna 1811. In some embodiments, WD 1810 may not include separate radio front end circuitry 1812; rather, processing circuitry 1820 can comprise radio front end circuitry and can be connected to antenna 1811. Similarly, in some embodiments, some or all of RF transceiver circuitry 1822 can be considered a part of interface 1814. Radio front end circuitry 1812 can receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 1812 can convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1818 and/or amplifiers 1816. The radio signal can then be transmitted via antenna 1811. Similarly, when receiving data, antenna 1811 can collect radio signals which are then converted into digital data by radio front end circuitry 1812. The digital data can be passed to processing circuitry 1820. In other embodiments, the interface can comprise different components and/or different combinations of components.

Processing circuitry 1820 can comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other WD 1810 components, such as device readable medium 1830, WD 1810 functionality. Such functionality can include providing any of the various wireless features or benefits discussed herein.

For example, processing circuitry 1820 can execute instructions stored in device readable medium 1830 or in memory within processing circuitry 1820 to provide the functionality disclosed herein. As a more specific example, instructions (also referred to as a computer program product) stored in medium 1830 can include instructions that, when executed by processor 1820, can configure wireless device 1810 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein.

As illustrated, processing circuitry 1820 includes one or more of RF transceiver circuitry 1822, baseband processing circuitry 1824, and application processing circuitry 1826. In other embodiments, the processing circuitry can comprise different components and/or different combinations of components. In certain embodiments processing circuitry 1820 of WD 1810 can comprise a SOC. In some embodiments, RF transceiver circuitry 1822, baseband processing circuitry 1824, and application processing circuitry 1826 can be on separate chips or sets of chips. In alternative embodiments, part or all of baseband processing circuitry 1824 and application processing circuitry 1826 can be combined into one chip or set of chips, and RF transceiver circuitry 1822 can be on a separate chip or set of chips. In still alternative embodiments, part or all of RF transceiver circuitry 1822 and baseband processing circuitry 1824 can be on the same chip or set of chips, and application processing circuitry 1826 can be on a separate chip or set of chips. In yet other alternative embodiments, part or all of RF transceiver circuitry 1822, baseband processing circuitry 1824, and application processing circuitry 1826 can be combined in the same chip or set of chips. In some embodiments, RF transceiver circuitry 1822 can be a part of interface 1814. RF transceiver circuitry 1822 can condition RF signals for processing circuitry 1820.

In certain embodiments, some or all of the functionality described herein as being performed by a WD can be provided by processing circuitry 1820 executing instructions stored on device readable medium 1830, which in certain embodiments can be a computer- readable storage medium. In alternative embodiments, some or all of the functionality can be provided by processing circuitry 1820 without executing instructions stored on a separate or discrete device readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 1820 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 1820 alone or to other components of WD 1810, but are enjoyed by WD 1810 as a whole, and/or by end users and the wireless network generally.

Processing circuitry 1820 can be configured to perform any determining, calculating, or similar operations ( e.g ., certain obtaining operations) described herein as being performed by a WD. These operations, as performed by processing circuitry 1820, can include processing information obtained by processing circuitry 1820 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored by WD 1810, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Device readable medium 1830 can be operable to store a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 1820. Device readable medium 1830 can include computer memory ( e.g ., Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (e.g., a hard disk), removable storage media (e.g, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non- transitory device readable and/or computer executable memory devices that store information, data, and/or instructions that can be used by processing circuitry 1820. In some embodiments, processing circuitry 1820 and device readable medium 1830 can be considered to be integrated.

User interface equipment 1832 can include components that allow and/or facilitate a human user to interact with WD 1810. Such interaction can be of many forms, such as visual, audial, tactile, etc. User interface equipment 1832 can be operable to produce output to the user and to allow and/or facilitate the user to provide input to WD 1810. The type of interaction can vary depending on the type of user interface equipment 1832 installed in WD 1810. For example, if WD 1810 is a smart phone, the interaction can be via a touch screen; if WD 1810 is a smart meter, the interaction can be through a screen that provides usage (e.g, the number of gallons used) or a speaker that provides an audible alert (e.g, if smoke is detected). User interface equipment 1832 can include input interfaces, devices and circuits, and output interfaces, devices and circuits. User interface equipment 1832 can be configured to allow and/or facilitate input of information into WD 1810, and is connected to processing circuitry 1820 to allow and/or facilitate processing circuitry 1820 to process the input information. User interface equipment 1832 can include, for example, a microphone, a proximity or other sensor, keys/buttons, a touch display, one or more cameras, a USB port, or other input circuitry. User interface equipment 1832 is also configured to allow and/or facilitate output of information from WD 1810, and to allow and/or facilitate processing circuitry 1820 to output information from WD 1810. User interface equipment 1832 can include, for example, a speaker, a display, vibrating circuitry, a USB port, a headphone interface, or other output circuitry. Using one or more input and output interfaces, devices, and circuits, of user interface equipment 1832, WD 1810 can communicate with end users and/or the wireless network, and allow and/or facilitate them to benefit from the functionality described herein.

Auxiliary equipment 1834 is operable to provide more specific functionality which may not be generally performed by WDs. This can comprise specialized sensors for doing measurements for various purposes, interfaces for additional types of communication such as wired communications etc. The inclusion and type of components of auxiliary equipment 1834 can vary depending on the embodiment and/or scenario.

Power source 1836 can, in some embodiments, be in the form of a battery or battery pack. Other types of power sources, such as an external power source ( e.g ., an electricity outlet), photovoltaic devices or power cells, can also be used. WD 1810 can further comprise power circuitry 1837 for delivering power from power source 1836 to the various parts of WD 1810 which need power from power source 1836 to carry out any functionality described or indicated herein. Power circuitry 1837 can in certain embodiments comprise power management circuitry. Power circuitry 1837 can additionally or alternatively be operable to receive power from an external power source; in which case WD 1810 can be connectable to the external power source (such as an electricity outlet) via input circuitry or an interface such as an electrical power cable. Power circuitry 1837 can also in certain embodiments be operable to deliver power from an external power source to power source 1836. This can be, for example, for the charging of power source 1836. Power circuitry 1837 can perform any converting or other modification to the power from power source 1836 to make it suitable for supply to the respective components of WD 1810.

Figure 19 illustrates one embodiment of a UE in accordance with various aspects described herein. As used herein, a user equipment or UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE can represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE can represent a device that is not intended for sale to, or operation by, an end user but which can be associated with or operated for the benefit of a user (e.g, a smart power meter). UE 19200 can be any UE identified by the 3^rd Generation Partnership Project (3 GPP), including a NB-IoT UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE. UE 1900, as illustrated in Figure 19, is one example of a WD configured for communication in accordance with one or more communication standards promulgated by the 3^rd Generation Partnership Project (3GPP), such as 3GPP’s GSM, UMTS, LTE, and/or 5G standards. As mentioned previously, the term WD and UE can be used interchangeable. Accordingly, although Figure 19 is a UE, the components discussed herein are equally applicable to a WD, and vice-versa.

In Figure 19, UE 1900 includes processing circuitry 1901 that is operatively coupled to input/output interface 1905, radio frequency (RF) interface 1909, network connection interface 1911, memory 1915 including random access memory (RAM) 1917, read-only memory (ROM) 1919, and storage medium 1921 or the like, communication subsystem 1931, power source 1933, and/or any other component, or any combination thereof. Storage medium 1921 includes operating system 1923, application program 1925, and data 1927. In other embodiments, storage medium 1921 can include other similar types of information. Certain UEs can utilize all of the components shown in Figure 19, or only a subset of the components. The level of integration between the components can vary from one UE to another UE. Further, certain UEs can contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

In Figure 19, processing circuitry 1901 can be configured to process computer instructions and data. Processing circuitry 1901 can be configured to implement any sequential state machine operative to execute machine instructions stored as machine- readable computer programs in the memory, such as one or more hardware-implemented state machines ( e.g ., in discrete logic, FPGA, ASIC, etc.); programmable logic together with appropriate firmware; one or more stored program, general-purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 1901 can include two central processing units (CPUs). Data can be information in a form suitable for use by a computer.

In the depicted embodiment, input/output interface 1905 can be configured to provide a communication interface to an input device, output device, or input and output device. UE 1900 can be configured to use an output device via input/output interface 1905. An output device can use the same type of interface port as an input device. For example, a USB port can be used to provide input to and output from UE 1900. The output device can be a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. UE 1900 can be configured to use an input device via input/output interface 1905 to allow and/or facilitate a user to capture information into UE 1900. The input device can include a touch-sensitive or presence- sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display can include a capacitive or resistive touch sensor to sense input from a user. A sensor can be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, another like sensor, or any combination thereof. For example, the input device can be an accelerometer, a magnetometer, a digital camera, a microphone, and an optical sensor. In Figure 19, RF interface 1909 can be configured to provide a communication interface to RF components such as a transmitter, a receiver, and an antenna. Network connection interface 1911 can be configured to provide a communication interface to network 1943a. Network 1943a can encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 1943a can comprise a Wi-Fi network. Network connection interface 1911 can be configured to include a receiver and a transmitter interface used to communicate with one or more other devices over a communication network according to one or more communication protocols, such as Ethernet, TCP/IP, SONET, ATM, or the like. Network connection interface 1911 can implement receiver and transmitter functionality appropriate to the communication network links ( e.g ., optical, electrical, and the like). The transmitter and receiver functions can share circuit components, software or firmware, or alternatively can be implemented separately.

RAM 1917 can be configured to interface via bus 1902 to processing circuitry 1901 to provide storage or caching of data or computer instructions during the execution of software programs such as the operating system, application programs, and device drivers. ROM 1919 can be configured to provide computer instructions or data to processing circuitry 1901. For example, ROM 1919 can be configured to store invariant low-level system code or data for basic system functions such as basic input and output (EO), startup, or reception of keystrokes from a keyboard that are stored in a non-volatile memory. Storage medium 1921 can be configured to include memory such as RAM, ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, floppy disks, hard disks, removable cartridges, or flash drives.

In one example, storage medium 1919 can be configured to include operating system 1923, application program 1925 such as a web browser application, a widget or gadget engine or another application, and data file 1927. Storage medium 1919 can store, for use by UE 1900, any of a variety of various operating systems or combinations of operating systems. For example, application program 1925 can include executable program instructions (also referred to as a computer program product) that, when executed by processor 1901, can configure UE 1900 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein. Storage medium 1921 can be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), floppy disk drive, flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a subscriber identity module or a removable user identity (SIM/RUIM) module, other memory, or any combination thereof. Storage medium 1921 can allow and/or facilitate UE 1900 to access computer-executable instructions, application programs or the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system can be tangibly embodied in storage medium 1921, which can comprise a device readable medium.

In Figure 19, processing circuitry 1901 can be configured to communicate with network 1943b using communication subsystem 1931. Network 1943a and network 1943b can be the same network or networks or different network or networks. Communication subsystem 1931 can be configured to include one or more transceivers used to communicate with network 1943b. For example, communication subsystem 1931 can be configured to include one or more transceivers used to communicate with one or more remote transceivers of another device capable of wireless communication such as another WD, UE, or base station of a radio access network (RAN) according to one or more communication protocols, such as IEEE 802.19, CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, or the like. Each transceiver can include transmitter 1933 and/or receiver 1935 to implement transmitter or receiver functionality, respectively, appropriate to the RAN links ( e.g ., frequency allocations and the like). Further, transmitter 1933 and receiver 1935 of each transceiver can share circuit components, software or firmware, or alternatively can be implemented separately.

In the illustrated embodiment, the communication functions of communication subsystem 1931 can include data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. For example, communication subsystem 1931 can include cellular communication, Wi-Fi communication, Bluetooth communication, and GPS communication. Network 1943b can encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 1943b can be a cellular network, a Wi-Fi network, and/or a near-field network. Power source 1913 can be configured to provide alternating current (AC) or direct current (DC) power to components of UE 1900.

The features, benefits and/or functions described herein can be implemented in one of the components of UE 1900 or partitioned across multiple components of UE 1900. Further, the features, benefits, and/or functions described herein can be implemented in any combination of hardware, software or firmware. In one example, communication subsystem 1931 can be configured to include any of the components described herein. Further, processing circuitry 1901 can be configured to communicate with any of such components over bus 1902. In another example, any of such components can be represented by program instructions stored in memory that when executed by processing circuitry 1901 perform the corresponding functions described herein. In another example, the functionality of any of such components can be partitioned between processing circuitry 1901 and communication subsystem 1931. In another example, the non-computationally intensive functions of any of such components can be implemented in software or firmware and the computationally intensive functions can be implemented in hardware.

Figure 20 is a schematic block diagram illustrating a virtualization environment 2000 in which functions implemented by some embodiments can be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which can include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to a node ( e.g ., a virtualized base station or a virtualized radio access node) or to a device (e.g., a UE, a wireless device or any other type of communication device) or components thereof and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components (e.g, via one or more applications, components, functions, virtual machines or containers executing on one or more physical processing nodes in one or more networks).

In some embodiments, some or all of the functions described herein can be implemented as virtual components executed by one or more virtual machines implemented in one or more virtual environments 2000 hosted by one or more of hardware nodes 2030. Further, in embodiments in which the virtual node is not a radio access node or does not require radio connectivity (e.g, a core network node), then the network node can be entirely virtualized. The functions can be implemented by one or more applications 2020 (which can alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) operative to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. Applications 2020 are run in virtualization environment 2000 which provides hardware 2030 comprising processing circuitry 2060 and memory 2090. Memory 2090 contains instructions 2095 executable by processing circuitry 2060 whereby application 2020 is operative to provide one or more of the features, benefits, and/or functions disclosed herein.

Virtualization environment 2000 comprises general-purpose or special-purpose network hardware devices 2030 comprising a set of one or more processors or processing circuitry 2060, which can be commercial off-the-shelf (COTS) processors, dedicated Application Specific Integrated Circuits (ASICs), or any other type of processing circuitry including digital or analog hardware components or special purpose processors. Each hardware device can comprise memory 2090-1 which can be non-persistent memory for temporarily storing instructions 2095 or software executed by processing circuitry 2060. For example, instructions 2095 can include program instructions (also referred to as a computer program product) that, when executed by processing circuitry 2060, can configure hardware node 2020 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein. Such operations can also be attributed to virtual node(s) 2020 that is/are hosted by hardware node 2030.

Each hardware device can comprise one or more network interface controllers (NICs) 2070, also known as network interface cards, which include physical network interface 2080. Each hardware device can also include non-transitory, persistent, machine-readable storage media 2090-2 having stored therein software 2095 and/or instructions executable by processing circuitry 2060. Software 2095 can include any type of software including software for instantiating one or more virtualization layers 2050 (also referred to as hypervisors), software to execute virtual machines 2040 as well as software allowing it to execute functions, features and/or benefits described in relation with some embodiments described herein.

Virtual machines 2040 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and can be run by a corresponding virtualization layer 2050 or hypervisor. Different embodiments of the instance of virtual appliance 2020 can be implemented on one or more of virtual machines 2040, and the implementations can be made in different ways. During operation, processing circuitry 2060 executes software 2095 to instantiate the hypervisor or virtualization layer 2050, which can sometimes be referred to as a virtual machine monitor (VMM). Virtualization layer 2050 can present a virtual operating platform that appears like networking hardware to virtual machine 2040.

As shown in Figure 20, hardware 2030 can be a standalone network node with generic or specific components. Hardware 2030 can comprise antenna 20225 and can implement some functions via virtualization. Alternatively, hardware 2030 can be part of a larger cluster of hardware A. ., such as in a data center or customer premise equipment (CPE)) where many hardware nodes work together and are managed via management and orchestration (MANO) 20100, which, among others, oversees lifecycle management of applications 2020.

Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV can be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

In the context of NFV, virtual machine 2040 can be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of virtual machines 2040, and that part of hardware 2030 that executes that virtual machine, be it hardware dedicated to that virtual machine and/or hardware shared by that virtual machine with others of the virtual machines 2040, forms a separate virtual network elements (VNE).

Still in the context of NFV, Virtual Network Function (VNF) is responsible for handling specific network functions that run in one or more virtual machines 2040 on top of hardware networking infrastructure 2030 and corresponds to application 2020 in Figure 20.

In some embodiments, one or more radio units 20200 that each include one or more transmitters 20220 and one or more receivers 20210 can be coupled to one or more antennas 20225. Radio units 20200 can communicate directly with hardware nodes 2030 via one or more appropriate network interfaces and can be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station.

In some embodiments, some signalling can be effected with the use of control system 20230 which can alternatively be used for communication between the hardware nodes 2030 and radio units 20200.

With reference to Figure 21, in accordance with an embodiment, a communication system includes telecommunication network 2110, such as a 3GPP-type cellular network, 6q

which comprises access network 2111, such as a radio access network, and core network 2114. Access network 2111 comprises a plurality of base stations 2112a, 2112b, 2112c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 2113a, 2113b, 2113c. Each base station 2112a, 2112b, 2112c is connectable to core network 2114 over a wired or wireless connection 2115. A first UE 2191 located in coverage area 2113c can be configured to wirelessly connect to, or be paged by, the corresponding base station 2112c. A second UE 2192 in coverage area 2113a is wirelessly connectable to the corresponding base station 2112a. While a plurality of UEs 2191, 2192 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 base station 2112a.

Telecommunication network 2110 is itself connected to host computer 2130, which can 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. Host computer 2130 can be under the ownership or control of a service provider, or can be operated by the service provider or on behalf of the service provider. Connections 2121 and 2122 between telecommunication network 2110 and host computer 2130 can extend directly from core network 2114 to host computer 2130 or can go via an optional intermediate network 2120. Intermediate network 2120 can be one of, or a combination of more than one of, a public, private or hosted network; intermediate network 2120, if any, can be a backbone network or the Internet; in particular, intermediate network 2120 can comprise two or more sub-networks (not shown).

The communication system of Figure 21 as a whole enables connectivity between the connected UEs 2191, 2192 and host computer 2130. The connectivity can be described as an over-the-top (OTT) connection 2150. Host computer 2130 and the connected UEs 2191, 2192 are configured to communicate data and/or signaling via OTT connection 2150, using access network 2111, core network 2114, any intermediate network 2120 and possible further infrastructure (not shown) as intermediaries. OTT connection 2150 can be transparent in the sense that the participating communication devices through which OTT connection 2150 passes are unaware of routing of uplink and downlink communications. For example, base station 2112 may not or need not be informed about the past routing of an incoming downlink communication with data originating from host computer 2130 to be forwarded ( e.g ., handed over) to a connected UE 2191. Similarly, base station 2112 need not be aware of the future 6i

routing of an outgoing uplink communication originating from the UE 2191 towards the host computer 2130.

Example implementations, in accordance with an embodiment, of the EE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Figure 22. In communication system 2200, host computer 2210 comprises hardware 2215 including communication interface 2216 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of communication system 2200. Host computer 2210 further comprises processing circuitry 2218, which can have storage and/or processing capabilities. In particular, processing circuitry 2218 can comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. Host computer 2210 further comprises software 2211, which is stored in or accessible by host computer 2210 and executable by processing circuitry 2218. Software 2211 includes host application 2212. Host application 2212 can be operable to provide a service to a remote user, such as UE 2230 connecting via OTT connection 2250 terminating at UE 2230 and host computer 2210. In providing the service to the remote user, host application 2212 can provide user data which is transmitted using OTT connection 2250.

Communication system 2200 can also include base station 2220 provided in a telecommunication system and comprising hardware 2225 enabling it to communicate with host computer 2210 and with UE 2230. Hardware 2225 can include communication interface

2226 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of communication system 2200, as well as radio interface

2227 for setting up and maintaining at least wireless connection 2270 with UE 2230 located in a coverage area (not shown in Figure 22) served by base station 2220. Communication interface 2226 can be configured to facilitate connection 2260 to host computer 2210. Connection 2260 can be direct, or it can pass through a core network (not shown in Figure 22) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, hardware 2225 of base station 2220 can also include processing circuitry 2228, which can comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions.

Base station 2220 also includes software 2221 stored internally or accessible via an external connection. For example, software 2221 can include program instructions (also referred to as a computer program product) that, when executed by processing circuitry 2228, can configure base station 2220 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein.

Communication system 2200 can also include UE 2230 already referred to. The UE hardware 2235 can include radio interface 2237 configured to set up and maintain wireless connection 2270 with a base station serving a coverage area in which TIE 2230 is currently located. Hardware 2235 of TIE 2230 can also include processing circuitry 2238, which can comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions.

UE 2230 also includes software 2231, which is stored in or accessible by UE 2230 and executable by processing circuitry 2238. Software 2231 includes client application 2232. Client application 2232 can be operable to provide a service to a human or non-human user via UE 2230, with the support of host computer 2210. In host computer 2210, an executing host application 2212 can communicate with the executing client application 2232 via OTT connection 2250 terminating at UE 2230 and host computer 2210. In providing the service to the user, client application 2232 can receive request data from host application 2212 and provide user data in response to the request data. OTT connection 2250 can transfer both the request data and the user data. Client application 2232 can interact with the user to generate the user data that it provides. Software 2231 can also include program instructions (also referred to as a computer program product) that, when executed by processing circuitry 2238, can configure UE 2230 to perform operations corresponding to various exemplary methods (e.g., procedures) described herein.

It is noted that host computer 2210, base station 2220 and UE 2230 illustrated in Figure 22 can be similar or identical to host computer 2130, one of base stations 2112a, 2112b, 2112c and one of UEs 2191, 2192 of Figure 21, respectively. This is to say, the inner workings of these entities can be as shown in Figure 22 and independently, the surrounding network topology can be that of Figure 21.

In Figure 22, OTT connection 2250 has been drawn abstractly to illustrate the communication between host computer 2210 and UE 2230 via base station 2220, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure can determine the routing, which it can be configured to hide from UE 2230 or from the service provider operating host computer 2210, or both. While OTT connection 2250 is active, the network infrastructure can further take decisions by which it dynamically changes the routing ( e.g ., on the basis of load balancing consideration or reconfiguration of the network).

Wireless connection 2270 between UE 2230 and base station 2220 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to UE 2230 using OTT connection 2250, in which wireless connection 2270 forms the last segment. More precisely, the exemplary embodiments disclosed herein can improve flexibility for the network to monitor end-to-end quality-of-service (QoS) of data flows, including their corresponding radio bearers, associated with data sessions between a user equipment (UE) and another entity, such as an OTT data application or service external to the 5G network. These and other advantages can facilitate more timely design, implementation, and deployment of 5G/NR solutions. Furthermore, such embodiments can facilitate flexible and timely control of data session QoS, which can lead to improvements in capacitiy, throughput, latency, etc. that are envisioned by 5G/NR and important for the growth of OTT services.

A measurement procedure can be provided for the purpose of monitoring data rate, latency and other network operational aspects on which the one or more embodiments improve. There can further be an optional network functionality for reconfiguring OTT connection 2250 between host computer 2210 and UE 2230, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring OTT connection 2250 can be implemented in software 2211 and hardware 2215 of host computer 2210 or in software 2231 and hardware 2235 of UE 2230, or both. In embodiments, sensors (not shown) can be deployed in or in association with communication devices through which OTT connection 2250 passes; the sensors can participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 2211, 2231 can compute or estimate the monitored quantities. The reconfiguring of OTT connection 2250 can include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect base station 2220, and it can be unknown or imperceptible to base station 2220. Such procedures and functionalities can be known and practiced in the art. In certain embodiments, measurements can involve proprietary UE signaling facilitating host computer 2210’s measurements of throughput, propagation times, latency and the like. The measurements can be implemented in that software 2211 and 2231 causes messages to be transmitted, in particular empty or‘dummy’ messages, using OTT connection 2250 while it monitors propagation times, errors etc. Figure 23 is a flowchart illustrating an exemplary method and/or procedure implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which, in some exemplary embodiments, can be those described with reference to Figures 21 and 22. For simplicity of the present disclosure, only drawing references to Figure 23 will be included in this section. In step 2310, the host computer provides user data. In substep 2311 (which can be optional) of step 2310, the host computer provides the user data by executing a host application. In step 2320, the host computer initiates a transmission carrying the user data to the UE. In step 2330 (which can be optional), 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 step 2340 (which can also be optional), the UE executes a client application associated with the host application executed by the host computer.

Figure 24 is a flowchart illustrating an exemplary method and/or procedure implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which can be those described with reference to Figures 21 and 22. For simplicity of the present disclosure, only drawing references to Figure 24 will be included in this section. In step 2410 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 step 2420, the host computer initiates a transmission carrying the user data to the UE. The transmission can pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In step 2430 (which can be optional), the UE receives the user data carried in the transmission.

Figure 25 is a flowchart illustrating an exemplary method and/or procedure implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which can be those described with reference to Figures 21 and 22. For simplicity of the present disclosure, only drawing references to Figure 25 will be included in this section. In step 2510 (which can be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 2520, the UE provides user data. In substep 2521 (which can be optional) of step 2520, the UE provides the user data by executing a client application. In substep 2511 (which can be optional) of step 2510, 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 can further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in substep 2530 (which can be optional), transmission of the user data to the host computer. In step 2540 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 26 is a flowchart illustrating an exemplary method and/or procedure implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which can be those described with reference to Figures 21 and 22. For simplicity of the present disclosure, only drawing references to Figure 26 will be included in this section. In step 2610 (which can be optional), in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In step 2620 (which can be optional), the base station initiates transmission of the received user data to the host computer. In step 2630 (which can be optional), the host computer receives the user data carried in the transmission initiated by the base station.

As described herein, device and/or apparatus can be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of a device or apparatus, instead of being hardware implemented, be implemented as a software module such as a computer program or a computer program product comprising executable software code portions for execution or being run on a processor. Furthermore, functionality of a device or apparatus can be implemented by any combination of hardware and software. A device or apparatus can also be regarded as an assembly of multiple devices and/or apparatuses, whether functionally in cooperation with or independently of each other. Moreover, devices and apparatuses can be implemented in a distributed fashion throughout a system, so long as the functionality of the device or apparatus is preserved. Such and similar principles are considered as known to a skilled person.

Furthermore, functions described herein as being performed by a wireless device or a network node may be distributed over a plurality of wireless devices and/or network nodes. In other words, it is contemplated that the functions of the network node and wireless device described herein are not limited to performance by a single physical device and, in fact, can be distributed among several physical devices.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The term unit, as used herein, can have conventional meaning in the field of electronics, electrical devices and/or electronic devices and can include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.

In addition, certain terms used in the present disclosure, including the specification, drawings and exemplary embodiments thereof, can be used synonymously in certain instances, including, but not limited to, e.g ., data and information. It should be understood that, while these words and/or other words that can be synonymous to one another, can be used synonymously herein, that there can be instances when such words can be intended to not be used synonymously. Further, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly incorporated herein in its entirety. All publications referenced are incorporated herein by reference in their entireties.

As used herein unless expressly stated to the contrary, the phrases“at least one of’ and“one or more of,” followed by a conjunctive list of enumerated items (e.g,“A and B”, “A, B, and C”), are intended to mean“at least one item, with each item selected from the list consisting of’ the enumerated items. For example,“at least one of A and B” is intended to mean any of the following: A; B; A and B. Likewise,“one or more of A, B, and C” is intended to mean any of the following: A; B; C; A and B; B and C; A and C; A, B, and C.

As used herein unless expressly stated to the contrary, the phrase“a plurality of’ followed by a conjunctive list of enumerated items (e.g,“A and B”,“A, B, and C”) is intended to mean“multiple items, with each item selected from the list consisting of’ the enumerated items. For example,“a plurality of A and B” is intended to mean any of the following: more than one A; more than one B; or at least one A and at least one B.

The foregoing merely illustrates the principles of the disclosure. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures that, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the spirit and scope of the disclosure. Various exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art.

Example embodiments of the techniques and apparatus described herein include, but are not limited to, the following enumerated examples:

1. A method, performed by a source node, for beam-level mobility load balancing (MLB) in a radio access network (RAN), the method comprising:

receiving one or more measurement reports from a plurality of UEs, each

measurement report comprising radio measurements related to: a source beam transmitted by the source node; and

a plurality of target beams transmitted by one or more target nodes in the RAN;

based on the received measurement reports, sending a resource information

request, to a particular target node, for beam-level load-related information for one or more target beams of the particular target node;

receiving one or more resource information reports, from the particular target node, comprising the requested beam-level load-related information for the one or more target beams;

based on the measurement reports and the resource information reports, selecting at least one of the particular target beams for handover of a subset of the UEs from the source beam.

2. The method of embodiment 1, further comprising receiving, from the particular target node, a response acknowledging that resource information reports will be sent as requested by the source node.

3. The method of any of embodiments 1-2, further comprising performing a handover procedure with the particular target node with respect to the subset of UEs.

4. The method of embodiment 3, wherein performing the handover procecdure comprises sending, to the target node, that an indication the subset of UEs should be handed over to the selected target beams. 5. The method of any of embodiments 1-4, wherein the resource information request comprises information identifying one or more of the following for which reporting is requested:

the target beams;

a type of resource information;

a granularity of resource information;

one or more types of traffic;

one or more network slices; and

a reporting periodicity.

6. The method of embodiment 5, wherein the type of resource information comprises one or more of the following: traffic load, number of users, resource utilization, resource availability, and resource capacity.

7. The method of any of embodiments 5-6, wherein the granularity of resource information comprises one or more of the following: per SS/PBCH block (SSB), per channel state information reference signal (CSI-RS), per link beam, and per bandwidth part (BWP).

8. A method, performed by a target node, for beam -level mobility load balancing (MLB) in a radio access network (RAN), the method comprising:

receiving a resource information request, from a source node, for beam-level load- related information for one or more target beams of the target node;

determining beam-level load-related information, for the one or more target beams, based on one or more measurement reports from a plurality of UEs, each measurement report comprising radio measurements related to a plurality of target beams of the target node; and

sending one or more resource information reports, to the source target node,

comprising the determined beam-level load-related information.

9. The method of embodiment 8, further comprising sending, to the source node, a response acknowledging that resource information reports will be sent as requested by the source node. 10. The method of any of embodiments 8-9, further comprising performing a handover procedure, with the source node, with respect to a subset of the UEs served by a particular source beam of the source node.

11. The method of embodiment 10, wherein performing the handover procecdure comprises receiving, from the source node, an indication that the subset of UEs should be handed over to the selected target beams.

12. The method of any of embodiments 8-11, wherein:

each measurement report comprises signal strengths for each of the plurality of target beams; and

determining beam-level load-related information comprises, for each particular UE of the plurality of UEs, associating the particular UE with the target beam for which the particular UE reports the highest signal strength.

13. The method of any of embodiments 8-12, further comprising configuring the UEs to perform the radio measurements based on the resource information request.

14. The method of any of embodiments 8-13, wherein:

the method is performed by a centralized unit (CU) of the source node; and determining the beam-level load-related information comprises requesting, and receiving, the beam-level load-related information from one or more distributed units (DUs) associated with the CU.

15. The method of embodiment 14, wherein determining the beam-level load-related information comprises:

splitting the resource information request into a plurality of resource requests, each resource request associated with a different DU;

sending the plurality of resource requests to the respective DUs;

receiving a plurality of resource responses from the respective DUs; and aggregating the plurality of resource responses into the beam-level load-related information. 16. The method of any of embodiments 8-15, wherein the resource information request comprises information identifying one or more of the following for which reporting is requested:

the target beams;

a type of resource information;

a granularity of resource information;

one or more types of traffic;

one or more network slices; and

a reporting periodicity.

18. The method of embodiment 16, wherein the type of resource information comprises one or more of the following: traffic load, number of users, resource utilization, resource availability, and resource capacity.

19. The method of any of embodiments 16-17, wherein the granularity of resource information comprises one or more of the following: per SS/PBCH block (SSB), per channel state information reference signal (CSI-RS), per link beam, and per bandwidth part (BWP).

20. A network node in a radio access network (RAN), comprising:

communication circuitry configured to communicate with one or more other

network nodes and one or more user equipment (UE);

processing circuitry operably coupled to the communication circuitry and configured to perform operations corresponding to any of the methods of embodiments 1-19.

21. A network node configured for beam -level mobility load balancing (MLB) in a radio access network (RAN), the network node being arranged to perform operations

corresponding to any of the methods of embodiments 1-19.

22. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry comprising a network node in radio access network (RAN), configure the network node to perform operations corresponding to any of the methods of embodiments 1-19. A communication system including a host computer, the host computer comprising: a. processing circuitry configured to provide user data; and

b. a communication interface configured to forward the user data to a cellular network for transmission to a user equipment (UE) through a core network (CN) and a radio access network (RAN);

wherein:

c. the RAN comprises first and second nodes;

d. the first node comprises a communication transceiver and processing

circuitry configured to perform operations corresponding to any of the methods of embodiments 1-7; and

e. the second node comprises a communication transceiver and processing circuitry configured to perform operations corresponding to any of the methods of embodiments 8-19. The communication system of the previous embodiment, further comprising the UE. The communication system of any of the previous two embodiments, wherein: f. the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and

g. the UE comprises processing circuitry configured to execute a client

application associated with the host application. A method implemented in a communication system including a host computer, a cellular network, and a user equipment (UE), the method comprising:

a. at the host computer, providing user data;

b. at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising an radio access network (RAN); and c. operations, performed by first and second nodes of the RAN, corresponding to any of the methods of embodiments 1-19. The method of the previous embodiment, wherein the data message comprises the user data, and further comprising transmitting the user data to the UE via the first node or the second node. 28. The method of any of the previous two embodiments, wherein the user data is provided at the host computer by executing a host application, the method further comprising, at the UE, executing a client application associated with the host application.

29. 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) via a first node or a second node in a radio access network (RAN), wherein:

a. the first node comprises a communication interface and processing circuitry configured to perform operations corresponding to any of the methods of embodiments 1-7; and

b. the second node comprises a communication interface and processing

circuitry configured to perform operations corresponding to any of the methods of embodiments 8-19.

30. The communication system of the previous embodiment, further including the UE.

31. The communication system of any of the previous two embodiments, wherein:

c. the processing circuitry of the host computer is configured to execute a host application;

d. the UE is configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

Claims

1. A method, performed by a source node, for mobility load balancing, MLB, in a radio access network, RAN, the method comprising:

sending (1640) a resource information request, to a target node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN, wherein the resource information request identifies at least one of the following:

one or more first types of requested resource information; and one or more second types of resource granularity for which resource

information is requested; and

receiving (1660) one or more resource information reports, from the target node, including resource information according to one or more of the following: at least one of the first types, and

at least one of the second types.

2. The method of claim 1, wherein the second types of resource granularity include one or more of the following, including combinations thereof:

per SS/PBCH block, SSB, beam;

per channel state information reference signal, CSI-RS, beam;

per link beam;

per bandwidth part;

per network slice; and

per traffic type.

3. The method of any of claims 1-2, wherein the first types of resource information include one or more of the following:

traffic load information;

utilization of time-frequency resources;

available capacity;

number of user equipment, UEs; and

number of UEs in RRC CONNECTED mode.

4. The method of claim 3, wherein the resource information request also identifies one or more of the following for which resource information is requested:

one or more specific beams or specific groups of beams associated with the target node,

one or more cells associated with the specific beams or specific groups of beams; one or more of the first types,

one or more specific types of traffic, and

one or more specific network slices.

5. The method of claims 1-4, wherein the resource information request also identifies one or more of the following:

frequency or periodicity of resource information reports, and

timing of resource information reports.

6. The method of any of claims 1-5, wherein the resource information in each resource information report includes one or more of the following:

available capacity for one or more specific SS/PBCH block, SSB, beams or specific groups of SSB beams associated with the target node;

available capacity in a specific SSB beam for one or more specific network slices; available capacity in a cell for one or more specific network slices; and

utilization of time-frequency resources for one or more specific SSB beams or

specific groups of SSB beams associated with the target node.

7. The method of any of claims 1-6, wherein:

the method further comprises receiving (1610) one or more measurement reports from a first plurality of UEs, each measurement report including radio measurements related to the following:

a source beam or a source cell associated with the source node; and one or more target beams associated with the target node;

the resource information request is sent based on the received measurement reports.

8. The method of any of claims 1-7, further comprising receiving (1650), from the target node, a response acknowledging that resource information reports will be sent as requested by the source node.

9. The method of any of claims 7-8, further comprising:

based on the measurement reports and the resource information reports, selecting (1690) at least one of the target beams for handover of a subset of the first plurality of UEs from the source beam; and

performing (1695) a handover procedure with the target node with respect to the subset of UEs.

10. The method of claim 9, wherein:

performing (1695) the handover procedure comprises sending (1696), to the target node, an indication that a particular UE, of the subset of UEs, should be handed over to the selected target beams;

the selected target beams are respective SS/PBCH blocks, SSBs, having respective SSB coverage areas and associated with respective SSB indices;

the indication includes the respective SSB indices and indicates that the particular UE should be handed over to respective link beams having coverage areas overlapping with the SSB coverage areas.

11. The method of any of claims 1-10, wherein the method is performed by a centralized unit (CU) of the source node.

12. The method of claim 11, further comprising:

receiving (1620) further resource information requests from a plurality of

distributed units (DUs) associated with the CU;

aggregating (1630) the further resource information requests into the resource information request sent to the target node;

splitting (1670) each of the received resource information reports into a plurality of further resource information reports, each associated with a different one of the DUs; and

sending (1680) the further resource information reports to the respective DUs.

13. The method of any of claims 11-12, wherein the target node is one of the following:

a further CU; or a further DU associated with the CU of the source node.

14. A method, performed by a target node, for mobility load balancing, MLB, in a radio access network, RAN, the method comprising:

receiving (1710) a resource information request, from a source node in the RAN, for information about resources, associated with the target node, that are usable for mobility load balancing in the RAN, wherein the resource information request identifies one or more of the following: one or more first types of requested resource information, and one or more second types of resource granularity for which resource

information is requested; and

sending (1760) one or more resource information reports, to the source node, including resource information according to one or more of the following: at least one of the first types, and

at least one of the second types.

15. The method of claim 14, wherein the second types of resource granularity include one or more of the following, including combinations thereof:

per SS/PBCH block, SSB, beam;

per channel state information reference signal, CSI-RS, beam;

per link beam;

per bandwidth part;

per network slice; and

per traffic type.

16. The method of any of claims 14-15, wherein the first types of resource information include one or more of the following:

traffic load information;

utilization of time-frequency resources;

available capacity;

number of user equipment, UEs; and

number of UEs in RRC CONNECTED mode.

17. The method of claims 14-16, wherein the resource information request also identifies one or more of the following for which resource information is requested:

one or more specific types of traffic, and

one or more specific network slices.

18. The method of claims 14-17, wherein the resource information request also identifies one or more of the following:

frequency or periodicity of resource information reports, and

timing of resource information reports.

19. The method of any of claims 14-18, wherein the resource information in each resource information report includes one or more of the following:

utilization of time-frequency resources for one or more specific SSB beams or

specific groups of SSB beams associated with the target node.

20. The method of claims 14-19, further comprising sending (1720), to the source node, a response acknowledging that resource information reports will be sent as requested by the source node.

21. The method of claim 20, wherein the response also indicates at least one of the following that can be, or will be, included in the resource information reports:

one or more first types of resource information; and

one or more second types of resource granularity for the resource information.

22. The method of any of claims 19-21, further comprising performing (1770) a handover procedure, with the source node, with respect to one or more UEs served by a source beam associated with the source node.

23. The method of claim 22, wherein:

performing (1770) the handover procedure comprises receiving (1772), from the source node, an indication that a particular one of the UEs should be handed over to at least one of the target beams associated with the target node;

the at least one target beams are respective SS/PBCH blocks, SSBs, having

respective SSB coverage areas and associated with respective SSB indices; and

24. The method of any of claims 14-23, further comprising:

configuring (1730) measurements by a second plurality of UEs based on the

resource information request from the source node;

receiving (1740) measurement reports from the second plurality of UEs in

response to the configured measurements, wherein each measurement report includes radio measurements related to a plurality of target beams associated with the target node; and

determining (1750) the resource information, included in the resource information reports, based on the measurement reports.

25. The method of claim 24, wherein:

each measurement report includes signal strengths for the plurality of target

beams; and

determining (1750) the resource information comprises, for each particular UE of the second plurality of UEs, associating (1751) the particular UE with the target beam for which the particular UE reports the highest signal strength.

26. The method of claim 25, wherein determining (1750) the resource information further comprises, for each particular UE, correlating (1752) the particular UE’s associated target beam with one or more of the following:

resources scheduled by the target node for the particular UE; and

a traffic type requested by the particular UE.

27. The method of any of claims 14-26, wherein the method is performed by a centralized unit (CU) of the target node.

28. The method of claim 27, wherein determining (1750) the resource information comprises:

splitting (1753) the resource information request into a plurality of further resource information requests for a respective plurality of distributed units, DUs, associated with the CU;

sending (1754) the further resource information requests to the respective DUs; receiving (1755) a plurality of responses from the respective DUs; and

aggregating (1756) the plurality of responses into the resource information

included in the resource information reports.

29. The method of any of claims 27-28, wherein the source node is one of the following:

a further CU; or

a further distributed unit, DU, associated with the CU of the target node.

30. A network node (105-115, 310, 320, 400, 450, 1220, 1860, 2030, 2112, 2220) configured for beam -level mobility load balancing in a radio access network, RAN (100, 399, 499, 2111), the network node comprising:

communication interface circuitry (1890, 2070, 20200, 2226) configured to

communicate with one or more user equipment, UEs, and with a further network node in the RAN; and

processing circuitry (1870, 2060, 2228) operably coupled with the communication interface circuitry, whereby the processing circuitry and the communication 8q

interface circuitry are configured to perform operations corresponding to any of the methods of claims 1-13.

31. A network node (105-115, 310, 320, 400, 450, 1220, 1860, 2030, 2112, 2220) configured for beam-level mobility load balancing in a radio access network, RAN (100,

399, 499, 2111), the network node being further arranged to perform operations

corresponding to any of the methods of claims 1-13.

32. A non-transitory, computer-readable medium (1880, 2090) storing program instructions (0295, 2221) that, when executed by processing circuitry (1870, 2060, 2228) of a network node (105-115, 310, 320, 400, 450, 1220, 1860, 2030, 2112, 2220) of a radio access network, RAN (100, 399, 499, 2111), configure the network node to perform operations corresponding to any of the methods of claims 1-13.

33. A computer program product comprising program instructions (2095, 2221) that, when executed by processing circuitry (1870, 2060, 2228) of a network node (105-115, 310, 320, 400, 450, 1220, 1860, 2030, 2112, 2220) of a radio access network, RAN (100, 399, 499, 2111), configure the network node to perform operations corresponding to any of the methods of claims 1-13.

34. A network node (105-115, 310, 320, 400, 450, 1230, 1860, 2030, 2112, 2220) configured for beam-level mobility load balancing in a radio access network, RAN (100,

399, 499, 2111), the network node comprising:

communication interface circuitry (1890, 2070, 20200, 2226) configured to

processing circuitry (1870, 2060, 2228) operably coupled with the communication interface circuitry, whereby the processing circuitry and the communication interface circuitry are configured to perform operations corresponding to any of the methods of claims 14-29.

35. A network node (105-115, 310, 320, 400, 450, 1230, 1860, 2030, 2112, 2220) configured for beam-level mobility load balancing in a radio access network, RAN (100, 8l

399, 499, 2111), the network node being further arranged to perform operations

corresponding to any of the methods of claims 14-29.

36. A non-transitory, computer-readable medium (1880, 2090) storing program instructions (2095, 2221) that, when executed by processing circuitry (1870, 2060, 2228) of a network node (105-115, 310, 320, 400, 450, 1230, 1860, 2030, 2112, 2220) of a radio access network, RAN (100, 399, 499, 2111), configure the network node to perform operations corresponding to any of the methods of claims 14-29.

37. A computer program product comprising program instructions (2095, 2221) that, when executed by processing circuitry (1870, 2060, 2228) of a network node (105-115, 310, 320, 400, 450, 1230, 1860, 2030, 2112, 2220) of a radio access network, RAN (100, 399, 499, 2111), configure the network node to perform operations corresponding to any of the methods of claims 14-29.