WO2023277752A1 - Reporting erroneous reconfigurations - Google Patents

Abstract

Embodiments include methods for a user equipment (UE) configured to operate in a wireless network. Such methods include storing first reconfiguration information received from a first node serving a first cell in the wireless network. The first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells. Such methods include selecting a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with the first reconfiguration information and/orsecond reconfiguration information subsequently received from the first node. Such methods include, based on determining that the second cell is one of the candidate target cells, applying the stored conditional reconfiguration associated with the second cell and sending to the second node a first message including an indication that the UE applied the stored conditional reconfiguration when the UE was unable to comply with the information.

Description

REPORTING ERRONEOUS RECONFIGURATIONS TECHNICAL FIELD

The present disclosure relates generally to wireless communication networks and more specifically to techniques for improving various mobility operations that user equipment (UEs) perform in relation to cells in a wireless communication network.

BACKGROUND

Long-Term Evolution (LTE) is an umbrella term for so-called fourth-generation (4G) radio access technologies developed within the Third-Generation Partnership Project (3 GPP) and initially standardized in Release 8 (Rel-8) and Release 9 (Rel-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.

Figure 1 shows an exemplary architecture of an LTE network. E-UTRAN 100 includes 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 can communicate with 3GPP-standard-compliant network equipment, including E-UTRAN as well as UTRAN and/or GERAN, as the third-generation (“3G”) and second-generation (“2G”) 3GPP RANs 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 115. Each of the eNBs can serve a geographic coverage area including one more cells, including cells 106, 111, and 115 served by eNBs 105, 110, and 115, respectively.

The eNBs in the E-UTRAN communicate with each other via the X2 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. In general, 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. HSS 131 can also communicate with MMEs 134 and 138 via respective S6a interfaces.

In some embodiments, HSS 131 can communicate with a user data repository (UDR) - labelled EPC-UDR 135 in Figure 1 - via a Ud interface. 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 2 illustrates a block diagram of an exemplary control plane (CP) 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 PDCP layer provides ciphering/deciphering and integrity protection for both CP and user plane (UP), as well as other UP functions such as header compression. The exemplary protocol stack also includes non-access stratum (NAS) signaling between the UE and the MME.

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 does not belong to any cell, no RRC context has been established for the UE (e.g., in E- UTRAN), and the UE is out of UL synchronization with the network. Even so, a UE in RRC IDLE state is known in the EPC and has an assigned IP address.

Furthermore, 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 “DRX 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 for pages from the EPC via an eNB serving the cell in which the UE is camping.

A UE must perform a random-access (RA) procedure to move from RRC IDLE to RRC CONNECTED state. In RRC CONNECTED state, the cell serving the UE is known and an RRC context is established for the UE in the serving eNB, such that the UE and eNB can communicate. For example, a Cell Radio Network Temporary Identifier (C-RNTI) - a UE identity used for signaling between UE and network - is configured for a UE in RRC CONNECTED state.

Logical channel communications between a UE and an eNB are via radio bearers. Since LTE Rel- 8, signaling radio bearers (SRBs) SRBO, SRB1, and SRB2 have been available for the transport of RRC and NAS messages. SRBO is used for RRC connection setup, RRC connection resume, and RRC connection re-establishment. Once any of these operations has succeeded, SRB1 is used for handling RRC messages (which may include a piggybacked NAS message) and for NAS messages prior to establishment of SRB2. SRB2 is used for NAS messages and lower- priority RRC messages (e.g., logged measurement information). SRBO and SRB1 are also used for establishment and modification of data radio bearers (DRBs) for carrying user data between the UE and eNB.

Currently the fifth generation (“5G”) of cellular systems, also referred to as New Radio (NR), is being standardized within the Third-Generation Partnership Project (3GPP). NR is developed for maximum flexibility to support a variety of different use cases. These include enhanced mobile broadband (eMBB), machine type communications (MTC), ultra-reliable low latency communications (URLLC), side-link device-to-device (D2D), and several other use cases. 5G/NR technology shares many similarities with fourth-generation LTE. For example, both PHYs utilize similar arrangements of time-domain physical resources into 1-ms subframes that include multiple slots of equal duration, with each slot including multiple OFDM-based symbols. As another example, NR RRC layer includes RRC IDLE and RRC CONNECTED states, but adds another state known as RRC INACTIVE. In addition to providing coverage via “cells,” as in LTE, NR networks also provide coverage via “beams.” In general, a DL “beam” is a coverage area of a network-transmitted RS that may be measured or monitored by a UE.

A common mobility procedure for UEs in RRC CONNECTED state is handover (HO) between from a source (or serving) cell provided by a source node to a target cell provided by a target node. In general, for LTE (or NR), handover source and target nodes are different eNBs (or NR gNBs), although intra-node handover between different cells served by a single eNB (or gNB) is also possible. Seamless handovers are a key feature of 3GPP technologies and ensure that UEs move around in a multi-cell coverage area without too many interruptions in data transmission. The concept of a successful handover report is described in 3GPP TR 37.816 (vl6.0.0) in relation to self-optimizing networks (SON) and minimization of drive testing (MDT). In general, this involves the UE sending additional information (e.g., radio conditions, failure possibilities, etc.) to the target cell upon successfully completing a handover. This additional information can facilitate tuning handover parameters by the network.

Even so, handover and other mobility procedures can have various problems related to robustness. For example, a HO command (e.g., RRCConnectionReconfiguration with mobilityControlInfo for LTE or RRCReconfiguration with a reconfigurationWithSync for NR) is normally sent when the radio conditions for the UE are already quite bad, such as at or near cell borders. As such, the HO command may need to be segmented (e.g., to allow for redundancy to protect against errors) and/or retransmitted one or more times before it reaches the UE. In such case, the HO command may not reach the UE in time (or at all) before the degraded connection with the source node (e.g., the node hosting the UE’s current serving cell) is dropped. Failure of handover to a target cell may lead to the UE declaring radio link failure (RLF) in the source cell. After the UE reestablishes a connection in another target cell, the UE can provide an RLF report to the network, indicating the cause(s) of the RLF in the source cell.

Some “conditional mobility” techniques (e.g., conditional handover, CHO) have been introduced to address various difficulties with handovers and other mobility procedures. A main principle is separation of transmission and execution of a mobility (e.g., handover) command. This allows the mobility command to be sent to the UE when the radio conditions are still adequate, thus increasing likelihood that the message is successfully sent. Execution of the mobility command is done at later point in time based on an associated execution condition.

SUMMARY

However, the UE can experience various problems, issues, and/or difficulties during a period between receiving and executing a conditional mobility command (e.g., CHO), such as when the UE receives certain other messages during that period.

Embodiments of the present disclosure provide specific improvements to mobility operations in a wireless network, such as by facilitating solutions to overcome exemplary problems summarized above and described in more detail below.

Embodiments include methods (e.g., procedures) for a user equipment (UE) configured to operate in a wireless network.

These exemplary methods can include storing first reconfiguration information received from a first node serving a first cell in the wireless network. The first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells. These exemplary methods can also include performing a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information. These exemplary methods can also include, based on determining that the second cell is one of the candidate target cells, applying the stored conditional reconfiguration associated with the second cell. These exemplary methods can also include sending, to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one information.

In some embodiments, the UE is operating in a connected state (e.g., RRC CONNECTED) when receiving the first reconfiguration information and these exemplary methods can also include, before performing the cell reselection procedure, transitioning to a non- connected state based on determining that the UE cannot comply with the at least one information.

In some embodiments, the first message is an RRCReconfigurationComplete message.

In other methods, these exemplary methods can also include the following operations: storing the first message in a successful handover report based on successfully applying the conditional reconfiguration associated with the second cell; sending, to the second node, a further indication that the successful handover report is available; and receiving, from the second node, a first request for the successful handover report. The first message is sent in response to the first request. In some of these embodiments, the further indication is sent in an RRCReconfigurationComplete message, the first request is included in a UEInformationRe quest message, and the first message is a UEInformationRe sponse message. In some of these embodiments, these exemplary methods can also include receiving, from the first node, a second request to store successful handover reports, such that the first message is stored based on the second request.

In some embodiments, the indication can include one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with:

• an identifier of a target cell,

• an identifier of a frequency used in the target cell, and

• an identifier of a portion of the information that the UE was unable to comply with.

In some of these embodiments, when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell. In some of these embodiments, when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following:

• the identifier of the candidate target cell associated with the particular conditional reconfiguration, and

• the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

In some of these embodiments, when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

Other embodiments include methods (e.g., procedures) for a first node (e.g., base station, eNB, gNB, ng-eNB, etc. or component thereof) configured to serve a first cell in a wireless network (e.g., E-UTRAN, NG-RAN).

These exemplary methods can include sending, to a UE, first reconfiguration information that includes one or more conditional reconfigurations associated with respective one or more candidate target cells. These exemplary methods can also include receiving, from a second node serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information.

In some embodiments, these exemplary methods can also include sending the UE second reconfiguration information, message, i.e., that the UE is unable to comply with as mentioned above.

In some embodiments, the UE is operating in a connected state (e.g., RRC CONNECTED) when the first reconfiguration information is sent. In some embodiments, these exemplary methods can also include sending, to the UE, a second request to store successful handover reports, such that the second message is received based on the second request.

In various embodiments, the indication can include any of the information and/or characteristics summarized above in relation to the UE embodiments.

Other embodiments include methods (e.g., procedures) for a second node (e.g., base station, eNB, gNB, ng-eNB, etc. or component thereof) configured to serve a second cell in a wireless network (e.g., E-UTRAN, NG-RAN).

These exemplary methods can include receiving, from a UE, a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: • first reconfiguration information received by the UE from a first node serving a first cell, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and

• second reconfiguration information received by the UE from the first node after the first reconfiguration information.

In some embodiments, these exemplary methods can also include sending, to the first node, a second message including the indication received in the first message.

In some embodiments, the first message is an RRCReconfigurationComplete message.

In other embodiments, these exemplary methods can also include receiving, from the UE, a further indication that a successful handover report is available; and send, to the UE, a first request for the successful handover report. The first message can be received in response to the first request. In some of these embodiments, the further indication is sent in an RRCReconfigurationComplete message, the first request is included in a UEInformationRe quest message, and the first message is a UEInformationResponse message.

In various embodiments, the indication can include any of the information and/or characteristics summarized above in relation to the UE embodiments.

Other embodiments include UEs (e.g, wireless devices, IoT devices, etc. or component(s) thereof) and network nodes (e.g, base stations, eNBs, gNBs, ng-eNBs, etc., or components thereof) configured to perform operations corresponding to any of the exemplary methods described herein. Other embodiments include non-transitory, computer-readable media storing program instructions that, when executed by processing circuitry, configure such UEs or network nodes to perform operations corresponding to any of the exemplary methods described herein.

These and other embodiments can facilitate a network node, serving the source cell in which a UE received a reconfiguration message with which the UE was unable to comply, to be aware of the problematic message and correct the construction of such messages sent to other UEs in the future. Furthermore, in case the problem concerns a conditional reconfiguration of a candidate target cell sent via the source cell, the network node can inform another network node that prepared the conditional reconfiguration about the problem, thereby facilitating similar correction by the other network node. At a high level, this can increase reliability of UE and network operations for mobility.

These and other objects, features, and 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 l is a high-level block diagram of an exemplary LTE network architecture.

Figure 2 is a block diagram of an exemplary LTE control plane (CP) protocol stack.

Figures 3 and 4A-B illustrate various aspects of dual connectivity (DC) in an LTE network.

Figure 5 is a high-level block diagram of an exemplary 5G network architecture.

Figures 6-7 show high-level views of exemplary network architectures that support multi- RAT DC (MR-DC) using EPC and 5GC, respectively.

Figure 8 is a block diagram showing a high-level comparison of CP architectures of two DC alternatives, EN-DC with EPC and MR-DC with 5GC, respectively.

Figure 9 shows exemplary network-side protocol termination options for signaling radio bearers (SRBs) in MR-DC.

Figure 10 illustrates an exemplary signal procedure for a conditional handover (CHO).

Figure 11 illustrates an exemplary signaling procedure between a UE, a first node serving a first cell, and a second node serving a second cell.

Figure 12 shows an ASN.l data structure for information elements (IEs) of an exemplary RRCReconfiguration message, according to various embodiments of the present disclosure.

Figure 13 shows an ASN.l data structure for an exemplary RRCReconfigurationComplete message, according to various embodiments of the present disclosure.

Figure 14 is a flow diagram of an exemplary method (e.g., procedure) for a UE (e.g., wireless device, IoT device, etc. or component thereof), according to various embodiments of the present disclosure.

Figure 15 is a flow diagram of an exemplary method (e.g., procedure) for a first node (e.g., base station, eNB, gNB, ng-eNB, en-gNB, etc. or component(s) thereof) of a wireless network, according to various embodiments of the present disclosure.

Figure 16 is a flow diagram of an exemplary method (e.g., procedure) for a second node (e.g., base station, eNB, gNB, ng-eNB, en-gNB, etc. or component(s) thereof) of a wireless network, according to various embodiments of the present disclosure.

Figure 17 shows a communication system according to various embodiments of the present disclosure.

Figure 18 shows a UE according to various embodiments of the present disclosure.

Figure 19 shows a network node according to various embodiments of the present disclosure.

Figure 20 shows host computing system according to various embodiments of the present disclosure. Figure 21 is a block diagram of a virtualization environment in which functions implemented by some embodiments of the present disclosure may be virtualized.

Figure 22 illustrates communication between a host computing system, a network node, and a UE via multiple connections, at least one of which is wireless, according to various 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.

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 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 may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features, and advantages of the enclosed embodiments will be apparent from the following description. 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 equivalently “radio network node,” “radio access network node,” or “RAN 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/en-gNB) in a 3GPP Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB/ng-eNB) in a 3GPP LTE network), base station distributed components (e.g., CU and DEI), base station control- and/or user-plane components (e.g., CU-CP, CU-UP), a high-power or macro base station, a low-power base station (e.g, micro, pico, femto, or home base station, or the like), an integrated access backhaul (IAB) node, a transmission point, a remote radio unit (RRU or RRH), 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 serving gateway (SGW), a Packet Data Network Gateway (P-GW), an access and mobility management function (AMF), a session management function (AMF), a user plane function (UPF), 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. Some examples of a wireless device include, but are not limited to, smart phones, mobile phones, cell phones, voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, gaming consoles or devices, music storage devices, playback appliances, wearable devices, wireless endpoints, mobile stations, tablets, laptops, laptop- embedded equipment (LEE), laptop-mounted equipment (LME), smart devices, wireless customer-premise equipment (CPE), mobile-type communication (MTC) devices, Internet-of-Things (IoT) devices, vehicle-mounted wireless terminal devices, etc. Unless otherwise noted, the term “wireless device” is used interchangeably herein with the term “user equipment” (or “UE” for short).

• Network Node: As used herein, a “network node” is any node that is either part of the radio access network (e.g, a radio access node or equivalent name discussed above) or of the core network (e.g, a core network node discussed above) 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 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 3 GPP system. Furthermore, although the term “cell” is used herein, it should be understood that (particularly with respect to 5G NR) beams may be used instead of cells and, as such, concepts described herein apply equally to both cells and beams.

As briefly mentioned above, a UE can experience various problems, issues, and/or difficulties during the period between receiving and executing a conditional mobility command such as CHO, including when the UE receives certain other messages during that period. This is discussed in more detail below, after the following description of NR network architecture and various aspects of dual connectivity (DC).

LTE Rel-10 supports bandwidths larger than 20 MHz. One important Rel-10 requirement is backward compatibility with Rel-8. As such, a wideband LTE Rel-10 carrier (e.g, >20 MHz) should appear as a plurality of carriers (“component carriers” or CCs) to a Rel-8 (“legacy”) terminal. Legacy terminals can be scheduled in all parts of the wideband Rel-10 carrier. One way to achieve this is by Carrier Aggregation (CA), whereby a Rel-10 terminal can receive multiple CCs, each preferably having the same structure as a Rel-8 carrier.

LTE dual connectivity (DC) was introduced in Rel-12. In DC operation, a UE in RRC CONNECTED state consumes radio resources provided by at least two different network points connected to one another with a non-ideal backhaul. In LTE, these two network points may be referred to as a “Master eNB” (MeNB) and a “Secondary eNB” (SeNB). More generally, the terms master node (MN), anchor node, and MeNB can be used interchangeably, while the terms secondary node (SN), booster node, and SeNB can also be used interchangeably. DC can be viewed as a special case of CA, in which the aggregated carriers (or cells) are provided by network nodes that are physically separated and not connected via a robust, high-capacity connection.

In DC, the UE is configured with a Master Cell Group (MCG) associated with the MN and a Secondary Cell Group (SCG) associated with the SN. Each of the CGs is a group of serving cells that includes one MAC entity, a set of logical channels with associated RLC entities, a primary cell (PCell), and optionally one or more secondary cells (SCells). The term “Special Cell” (or “SpCell” for short) refers to the PCell of the MCG or the PSCell of the SCG depending on whether the UE’s MAC entity is associated with the MCG or the SCG, respectively. In non-DC operation (e.g, CA), SpCell refers to the PCell. An SpCell is always activated and supports physical uplink control channel (PUCCH) transmission and contention-based random access by UEs.

The MN provides system information (SI) and terminates the control plane connection towards the UE and, as such, is the controlling node of the UE, including handovers to and from SNs. In LTE DC, for example, the MN terminates the connection between the eNB and the Mobility Management Entity (MME) for the UE. An SN provides additional radio resources (e.g, bearers) for radio resource bearers include MCG bearers, SCG bearers, and split bearers that have resources from both MCG and SCG. It is also possible to support CA in either or both of MCG and SCG. In other words, either or both of the MCG and the SCG can include multiple cells working in CA.

The RRC layer also controls mobility procedures related to DC. For example, an SN Addition procedure is initiated by the MN and is used to establish a UE context at the SN to provide resources from the SN to the UE. As another example, the MN or SN can initiate an SN modification procedure to perform configuration changes of the SCG within the SN (“intra-SN”), e.g., modification/release of UP resource configuration and PSCell changes. For PSCell changes, once a better cell in the same frequency as the UE’s current PSCell triggers an event, a UE measurement report and preparation of the target SN is needed before the RRCReconfiguration to execute addition/modification can be sent to the UE. When adding a new SCell, dedicated RRC signaling is used to send the UE all required SI of the SCell, such that UEs need not acquire SI directly from the SCell broadcast.

Figure 3 shows an aggregated user plane (UP) protocol stack for LTE DC, while Figure 4A shows the inter-eNB connectivity for the LTE DC UP. The UP aggregation shown in Figure 3 achieves benefits such as increasing the throughput for users with good channel conditions and the capability of receiving and transmitting at higher data rates than can be supported by a single node, even without a low-latency backhaul connection between MeNB/MN and SeNB/SN.

As shown in Figure 3, the LTE DC UP includes three different types of bearers. MCG bearers are terminated in the MN, and the Sl-U connection for the corresponding bearer(s) to the S-GW is terminated in the MN (shown in Figure 4A). The SN is not involved in the transport of UP data for MCG bearers. Likewise, SCG bearers are terminated in the SN, which can be directly connected with the S-GW via Sl-U (as shown in Figure 4A). The MN is not involved in the transport of UP data for SCG bearers. An Sl-U connection between S-GW and SN is only present if SCG bearers are configured. Finally, split bearers are also terminated in the MN, with PDCP data being transferred between MN and SN via X2-U interface (shown in Figure 4A). Both SN and MN are involved in transmitting data for split bearers.

Figure 4B shows the inter-eNB CP connectivity for LTE DC. In this arrangement, all MME signaling is carried over the MeNB’s Sl-MME interface to the MME, with the SeNB’s signaling also carried over the X2-C interface with the MeNB. The network’s RRC connection with the UE is handled only by the MeNB, such that SRBs are always configured as MCG bearer type and only use radio resources of the MeNB. However, the MeNB can also configure the UE based on input from the SeNB and, in this manner, the SeNB can indirectly control the UE.

Figure 5 illustrates a high-level view of the 5G network architecture, consisting of a Next Generation RAN (NG-RAN) 599 and a 5G Core (5GC) 598. NG-RAN 599 can include a set of gNodeB’s (gNBs) connected to the 5GC via one or more NG interfaces, such as gNBs 500, 550 connected via interfaces 502, 552, respectively. In addition, the gNBs can be connected to each other via one or more Xn interfaces, such as Xn interface 540 between gNBs 500 and 550. With respect the NR interface to UEs, each of the gNBs can support frequency division duplexing (FDD), time division duplexing (TDD), or a combination thereof.

NG-RAN 599 is layered into a Radio Network Layer (RNL) and a Transport Network Layer (TNL). The NG-RAN architecture, /. e. , the NG-RAN logical nodes and interfaces between them, is defined as part of the RNL. For each NG-RAN interface (NG, Xn, FI) the related TNL protocol and the functionality are specified. The TNL provides services for user plane transport and signaling transport. In some exemplary configurations, each gNB is connected to all 5GC nodes within an “AMF Region,” with the term AMF being discussed in more detail below.

The NG RAN logical nodes shown in Figure 5 include a central (or centralized) unit (CU or gNB-CU) and one or more distributed (or decentralized) units (DU or gNB-DU). For example, gNB 500 includes gNB-CU 510 and gNB-DUs 520 and 530. CUs are logical nodes that host higher-layer protocols and perform various gNB functions such controlling the operation of DUs. DUs are logical nodes that host lower-layer protocols and can include 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, communication interface circuitry ( e.g ., transceivers), and power supply circuitry.

A gNB-CU connects to gNB-DUs over respective FI logical interfaces, such as interfaces 522 and 532 shown in Figure 5. The gNB-CU and connected gNB-DUs are only visible to other gNBs and the 5GC as a gNB. In other words, the FI interface is not visible beyond gNB-CU. In the gNB split CU-DU architecture illustrated by Figure 4, DC can be achieved by allowing a UE to connect to multiple DUs served by the same CU or by allowing a UE to connect to multiple DUs served by different CUs.

3GPP TR 38.804 (vl4.0.0) describes various the following DC scenarios or configurations in which the MN and SN can apply either NR RAT, LTE RAT, or both, and can connect to either EPC or 5GC:

• DC: LTE DC (i.e., both MN and SN employ LTE, as discussed above);

• EN-DC: LTE -NR DC where MN (eNB) employs LTE and SN (gNB) employs NR, and both are connected to EPC.

• NGEN-DC: LTE -NR dual connectivity where a UE is connected to one ng-eNB that acts as a MN and one gNB that acts as a SN. The ng-eNB is connected to the 5GC and the gNB is connected to the ng-eNB via the Xn interface. • NE-DC: LTE-NR dual connectivity where a UE is connected to one gNB that acts as a MN and one ng-eNB that acts as a SN. The gNB is connected to 5GC and the ng-eNB is connected to the gNB via the Xn interface.

• NR-DC (or NR-NR DC): both MN and SN employ NR and connect to 5GC via NG.

• MR-DC (multi-RAT DC): a generalization of the Intra-E-UTRA Dual Connectivity (DC) described in 3GPP TS 36.300 (vl6.0.0), where a multiple Rx/Tx EGE may be configured to utilize resources provided by two different nodes connected via non-ideal backhaul, one providing E-UTRA access and the other one providing NR access. One node acts as the MN and the other as the SN, with one using LTE and the other using NR. The MN and SN are connected via a network interface and at least the MN is connected to the core network. EN-DC, NE-DC, and NGEN-DC are different example cases of MR-DC.

Figure 6 shows a high-level view of an exemplary network architecture that supports EN- DC, including an E-UTRAN 699 and an EPC 698. As shown in the figure, E-UTRAN 699 can include en-gNBs (e.g, 610a,b) and eNBs (e.g, 620a, b) that are interconnected with each other via respective X2 (or X2-U) interfaces. The eNBs shown in Figure 6 can be similar to the eNBs shown in Figure 1, while the ng-eNBs shown in Figure 6 can be similar to the gNBs shown in Figure 5 except that they connect to EPC 698 via an S 1 -U interface rather than to a 5GC via an X2 interface. The eNBs also connect to EPC 698 via an SI interface, like the arrangement shown in Figure 1. More specifically, the en-gNBs and eNBs connect to MMEs (e.g, 630a, b) and S-GWs (e.g., S- 640a, b) in EPC 698.

Each of the en-gNBs and eNBs can serve a geographic coverage area including one more cells, such as exemplary cells 611a-b and 621a-b shown in Figure 6. Depending on the cell in which it is located, a UE 605 can communicate with an en-gNB or eNB serving that cell via the NR or LTE radio interface, respectively. In addition, UE 605 can be in EN-DC connectivity with a first cell served by an eNB and a second cell served by an en-gNB, such as cells 620a and 610a shown in Figure 6.

Figure 7 shows a high-level view of an exemplary network architecture that supports MR- DC configurations based on a 5GC. More specifically, Figure 7 shows an NG-RAN 799 and a 5GC 798. NG-RAN 799 can include gNBs (e.g, 710a, b) and ng-eNBs (e.g, 720a, 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 798, more specifically to an Access and Mobility Management Function (AMF, e.g, 730a, b) via respective NG-C interfaces and to a User Plane Function (UPF, e.g, 740a, b) via respective NG-U interfaces. Moreover, the AMFs can communicate with one or more session management functions (SMFs, e.g., 750a, b) and network exposure functions (NEFs, e.g., 760a, b). Each of the gNBs shown in Figure 7 can be similar to gNBs shown in Figure 5, while each of the ng-eNBs shown in Figure 7 can be similar to eNBs shown in Figure 1 except that they connect to 5GC 798 via an NG interface rather than to an EPC via an SI interface. Each of the gNBs and ng-eNBs can serve a geographic coverage area including one more cells, such as exemplary cells 711a-b and 721a-b shown in Figure 7. The gNBs and ng-eNBs can also use various directional beams to provide coverage in the respective cells. Depending on the cell in which it is located, a EE 705 can communicate with the gNB or ng-eNB serving that cell via the NR or LTE radio interface, respectively. In addition, UE 705 can be in MR-DC connectivity with a first cell served by an ng-eNB and a second cell served by a gNB, such as cells 720a and 710a shown in Figure 7.

Figure 8 is a block diagram showing a high-level comparison of control plane (CP) architectures in EN-DC with EPC (e.g., Figure 6) and MR-DC with 5GC (e.g., Figure 7). The particular RATs used by MN and SN in these two architectures are shown in parentheses and discussed in more detail above. In either case, the UE has a single RRC state based on the MN RRC (LTE or NR) and a single CP connection towards the CN via Uu interface to MN and Sl-C or NG-C interface to CN. RRC PDUs generated by the SN can be transported via the X2-C or Xn- C interface to the MN and the Uu interface from MN to UE. The MN always sends the initial SN RRC configuration via MCG SRB (SRBl), but subsequent reconfigurations may be transported via MN or SN. When transporting RRC PDU from the SN, the MN does not modify the UE configuration provided by the SN.

As shown in Figure 8, each of MN and SN has an RRC entity for creating RRC Information Elements (IE) and messages for configuring the UE. Since the SN is responsible for its own resources, it provides the UE with the SCG configuration in an RRC message and also the radio bearer configuration in an IE, for all bearers that are terminated in the SN. The MN in turn creates the MCG configuration and the radio bearer configuration for all bearers terminated in the MN. The cell group configuration includes the configuration of LI (physical layer), MAC and RLC. The radio bearer configuration includes the configuration of PDCP (and SDAP in case of 5GC).

Figure 9 shows exemplary network-side protocol termination options for SRBs in MR- DC, including EN-DC with EPC. The MN sends the initial SN RRC configuration via MCG SRB (SRBl), but subsequent RRC configurations created by the SN can be sent to the UE either via the MN using SRBl or directly to the UE using SRB3 (if configured). For the SRBl case, the MN receives from the SN an RRC message containing the SCG configuration and an IE containing the radio bearer configuration. The MN encapsulates these into the RRC message it creates itself, that may also include changes to the MCG configuration and radio bearer configuration of bearers terminated in the MN. Thereby, the MCG and SCG configurations may be sent to the UE in the same RRC message.

For E-UTRAN (e g., eNB) connected to EPC, SRB1 uses E-UTRA PDCP at initial connection establishment. If the UE supports EN-DC (regardless of whether EN-DC is configured), after initial connection establishment the network can configure both MCG SRB1 and SRB2 to use either E-UTRA PDCP or NR PDCP. Change from E-UTRA PDCP to NR PDCP (or vice-versa) is supported via a handover procedure (e.g., reconfiguration with mobility) or, for the initial change of SRB1 from E-UTRA PDCP to NR PDCP, with a reconfiguration without mobility before the initial security activation.

If the SN is a gNB (i.e., for EN-DC, NGEN-DC, and NR-DC), the UE can be configured to establish SRB3 with the SN to enable RRC PDUs for the SN to be sent directly between the UE and the SN. RRC PDUs for the SN can only be transported directly to the UE for SN RRC reconfiguration not requiring any coordination with the MN. Measurement reporting for mobility within the SN can be done directly from the UE to the SN if SRB3 is configured.

Split SRB uses the NR PDCP layer and is supported for all MR-DC options, allowing duplication of RRC PDUs generated by the MN. For example, split SRB1 can be used to create diversity. From RRC point of view, it operates like normal SRB1 but on the PDCP layer, the sender can choose to send an RRC message via MN (MCG), via SN (SCG), or duplicated via MCG and SCG. In the DL, the path switching between MCG, SCG, or duplication is left to network implementation while the network configures UEs to use the MCG, SCG, or duplication in the UL. Subsequently, the terms “link”, “leg”, “path”, and “RLC bearer” are used interchangeably to refer to UE-MN and UE-SN communications.

As briefly mentioned above, the concept of a successful handover report is described in 3GPP TR 37.816 (vl6.0.0) in relation to self-optimizing networks (SON) and minimization of drive testing (MDT). In general, this involves the UE sending additional information (e.g., radio conditions, failure possibilities, etc.) to the target cell upon successfully completing a handover. This additional information can facilitate tuning handover parameters by the network. Relevant portions of 3GPP TR 37.816 are given below.

*** Begin text from 3GPP TR 37.816 ***

5.3.2.5 Successful HO Report

The MRO function in NR could be enhanced to provide a more robust mobility via reporting failure events observed during successful handovers. A solution to this problem is to configure the UE to compile a report associated to a successful handover comprising a set of measurements collected during the handover phase, i.e., measurement at the handover trigger, measurement at the end of handover execution or measurement after handover execution. The UE could be configured with triggering conditions to compile the Successful Handover Report, such that the report would be triggered only when the conditions are met. This limits UE reporting to relevant cases such as underlying issues detected by RLM or BFD detected upon a successful handover event.

The availability of a Successful Handover Report may be indicated by the Handover Complete message (RRCReconfigurationComplete) transmitted from UE to target NG-RAN node over RRC. The target NG-RAN node may fetch information of a successful handover report via UE Information Request/Response mechanism. In addition, the target NG-RAN node could then forward the Successful Handover Report to the source NR-RAN node to indicate failures experienced during a successful handover event.

The information contained in the successful handover report may comprise:

- RLM related information

- RLM related timers (e.g., T310, T312)

- Measurements of reference signals used for RLM in terms of RSRP, RSRQ, SINR

- RLC retransmission counter

- Beam failure detection (BFD) related information

- Detection indicators and counters (e.g., Qin and Qout indications)

- Measurements of reference signals used in BFD in terms of RSRP, RSRQ, SINR

- Handover related information

- Measurements of the configured reference signals at the time of successful handover

- SSB beam measurements

- CSI-RS measurements

- Handover related timers (e.g., T304)

- Measurement period indication, i.e., measurements are collected at handover trigger, at the end of handover execution or just after handover execution

Upon reception of a Successful HO Report, the receiving node is able to analyze whether its mobility configuration needs adjustment. Such adjustments may result in changes of mobility configurations, such as changes of RLM configurations or changes of mobility thresholds between the source and the target. In addition, target NG RAN node, in the performed handover, may further optimize the dedicated RACH-beam resources based on the beam measurements reported upon successful handovers.

*** End text from 3 GPP TR 37.816 ***

Even so, handovers are normally triggered when the UE is at the cell edge and is experiencing poor radio conditions. If the UE enters these conditions quickly, the conditions may already be so poor that the actual handover procedure may be hard to execute. Poor UE UL conditions may cause network failure to receive a measurement report transmitted by the UE; without this report, the network will not initiate the handover procedure. Poor UE DL conditions may cause UE failure to receive the handover command from the network (e.g., RRCReconfiguration with a reconfigurationWithSync field). Failed transmission of handover command is a common reason for unsuccessful handovers. Moreover, even if the command reaches the UE, DL messages are often segmented in poor radio conditions, which can increase the risk of retransmissions and a consequent delay in reaching the UE.

To improve mobility robustness and address the issues above, conditional handover (CHO) was introduced in 3GPP Rel-16. The key idea in CHO is separation of transmission and execution of the handover command. This allows the handover command to be sent to a UE earlier when the radio conditions are still good, thus increasing the likelihood that the message is successfully transferred. The execution of the handover command is done later in time based on an associated execution condition.

The execution condition is typically based on a threshold. For example, a signal strength of candidate target cell becomes X dB better than the serving cell (so called “A3 event”). A preceding measurement reporting event could use a threshold Y that is selected to be lower than X used as the handover execution condition. This allows the serving cell to prepare the handover upon reception of an early measurement report and to provide the RRCConnectionReconfiguration with mobilityControlInfo (for LTE), or a RRCReconfiguration with either a reconfigurationWithSync or a CellGroupConfig (for NR) at a time when the radio link between the source cell and the UE is still relatively stable.

As used herein, a cell for which conditional handover (or other conditional mobility procedure) is configured is called a “candidate target cell” or “potential target cell”. Similarly, a radio network node controlling a candidate/potential target cell is called “candidate target node” or “potential target node”. Once the CHO execution condition has been fulfilled for a candidate/potential target cell and CHO execution towards this cell has been triggered, this cell is no longer “potential” or a “candidate” in the normal senses of the words, since it is now certain that the CHO will be executed towards it. Hence, after the CHO execution condition has been fulfilled/triggered, the candidate/potential target cell can be referred to as the “target cell”.

Figure 10 illustrates an exemplary signal flow between a user equipment (UE) 1010, a first node 1020, and a second node 1030 for a CHO, according to embodiments of the present disclosure. The first and second nodes may also be referred to as source and target nodes, respectively. For example, the source and target nodes can be RAN nodes such as eNBs, ng-eNBs, gNBs and/or components of gNBs, such as CUs and/or DUs. This procedure involves two different measurement thresholds: a low threshold and a high threshold. The two thresholds can be expressed as different levels of a particular metric, e.g., signal strength, signal quality, etc. For example, the high threshold could be that the quality of the mobility reference signal (MRS) of the target cell or beam becomes X dB stronger than the MRS of the UE’s serving cell (e.g., provided by the source node), with the low threshold being less than the high threshold (i.e., target exceeds source by lower amount). As used in this context, MRS denotes a reference signal used for any mobility -related purpose. For example, in NR, MRS can be either SSB (SS/PBCH block) or CSI-RS. As a further example, for NR operating in unlicensed spectrum (referred to as NR-U), MRS can be a discovery reference signal (DRS) in addition to any of the signals mentioned above.

As an initial condition, the UE may be sending and/or receiving UP data with the source node in the UE’s serving cell. The UE can be provided with a measurement configuration including the low threshold (not shown in the figure). Upon performing measurements that meet the low threshold, the UE can send a measurement report to the source node (operation 1). While performing the measurements and evaluating the low threshold, the UE continues operating in its current RRC configuration. In operation 2, based on the measurement report in operation 1, the source node can decide to request an early handover of the UE to the target node (e.g., to a cell indicated in the measurement report). The source node sends a CHO request to the target node in operation 3. For example, the CHO request can include a Handover Preparationlnformation IE such as described above.

The target node accepts the CHO request and builds an RRC configuration for the UE (operation 4), then responds with a CHO request acknowledgement (operation 5) that includes the RRC configuration, similar to conventional handover. In operation 6, the source node then sends the UE a RRCReconfiguration message that includes a “CHO Configuration”, which can include the high threshold. After responding with an RRCReconfigurationComplete message (operation 7), the UE continues to perform measurements and whenever the high threshold condition is met for a target cell, it can detach from the source cell and, after synchronizing with the target cell, send the target node an RRCReconfigurationComplete message (e.g., operations 8-9). Even so, the UE can remain in the source cell for an extended amount of time in case the high threshold condition is not fulfilled.

In operation 10, the target node sends a HANDOVER SUCCESS message to the source gNB indicating the UE has successfully established the target connection. Upon reception of the handover success indication, the source node stops scheduling any further DL or UL data to the UE and sends an SN STATUS TRANSFER message to the target node indicating the latest PDCP SN transmitter and receiver status (operation 11). The source node now also starts to forward User Data to the target node (operation 12). Upon receiving the handover complete message (operation 9), the target node can start sending and/or receiving UP data with the UE. The target node also requests the AMF to switch the DL data path from the UPF from the source node to the target node (not shown). Once the path switch is completed the target node sends the UE CONTEXT RELEASE to the source node (operation 13).

The conditional handover concept shown above can be generalized into a generic conditional reconfiguration framework, wherein a UE may be configured in advance with other types of reconfigurations that can be executed by an RRCReconfiguration message (in NR.) or an RRCConnectionReconfiguration message (in LTE) when associated execution condition(s) is(are) triggered. Each such message is prepared by a candidate target node and associated with a candidate target cell and includes execution conditions that can be represented by one or more identifiers of measurement configuration(s). This conditional reconfiguration framework can be applied to the following mobility operations:

• Handover (e.g., target candidate RRCReconfiguration message contains a reconfiguration with sync for the MCG);

• PSCell Addition (e.g., target candidate RRCReconfiguration message contains an SCG configuration which contains a reconfiguration with sync for a cell to be the SpCell of the SCG);

• PSCell Change (e.g., target candidate RRCReconfiguration message contains an SCG configuration which contains a reconfiguration with sync for a new target candidate cell to be the new target SpCell of the SCG);

• PSCell Release (e.g., source RRCReconfiguration message to be conditionally applied contains an SCG release indication); or

• PSCell Suspend (e.g., source RRCReconfiguration message to be conditionally applied contains an SCG suspend indication).

When a UE is not configured with a CHO, if the UE receives an RRCReconfiguration message having portions with which the UE is unable to comply, then the UE performs a re establishment procedure. As part of the reestablishment procedure, the UE indicates to the network that re-establishment was performed due to ‘reconfigurationFailurek The following text from 3GPP TS 38.331 (vl6.4.0) is related to these operations, with underline used to indicate portions of particular interest to the present discussion.

*** Begin text from 3GPP TS 38.331 ***

5.3.5.8.2 Inability to comply with RRCReconfiguration

The UE shall: l>else if RRCReconfiguration is received via NR (i.e., NR standalone, NE-DC, or NR-DC): 2>if the UE is unable to comply with (part of) the configuration included in the RRCReconfiguration message received over SEB3;

NOTE 0: This case does not apply in NE-DC.

3>if the RRCReconfiguration message was received as part of ConditionalReconfiguration :

4> continue using the configuration used prior to when the inability to comply with the RRCReconfiguration message was detected;

3>else:

4> continue using the configuration used prior to the reception of RRCReconfiguration message;

3>if MCG transmission is not suspended:

4>initiate the SCG failure information procedure as specified in subclause 5.7.3 to report SCG reconfiguration error, upon which the connection reconfiguration procedure ends;

3>else:

4>initiate the connection re-establishment procedure as specified in clause 5.3.7, upon which the connection reconfiguration procedure ends;

2>else if the EE is unable to comply with (part of) the configuration included in the

RRCReconfiguration message received over the SRB1 or if the upper layers indicate that the nas-Container is invalid:

NOTE 0a: The compliance also covers the SCG configuration carried within octet strings e.g., field mrdc-SecondaryCellGroupConfig. I.e., the failure behaviour defined also applies in case the UE cannot comply with the embedded SCG configuration or with the combination of (parts of) the MCG and SCG configurations.

NOTE Ob: The compliance also covers the E-UTRA sidelink configuration carried within an octet string, e.g., field sl-ConfigDedicatedEUTRA. I.e., the failure behaviour defined also applies in case the UE cannot comply with the embedded E-UTRA sidelink configuration.

3>if the RRCReconfiguration message was received as part of ConditionalReconfiguration :

4> continue using the configuration used prior to when the inability to comply with the RRCReconfiguration message was detected;

3>else: 4> continue using the configuration used prior to the reception of RRCReconfiguration message;

3>if AS security has not been activated:

4> perform the actions upon going to RRC IDLE as specified in 5.3.11, with release cause 'other'

3>else if AS security has been activated but SRB2 and at least one DRB or, for LAB,

SRB2,have not been setup:

4> perform the actions upon going to RRC IDLE as specified in 5.3.11, with release cause 'RRC connection failure';

3>else:

4>initiate the connection re-establishment procedure as specified in 5 3 7. upon which the reconfiguration procedure ends:

5.3.7.4 Actions related to transmission of RRCReestablishmentRequest message l>set the reestablishmentCause as follows:

2>if the re-establishment procedure was initiated due to reconfiguration failure as specified in 5 3 5 8 2:

3>set the reestablishmentCause to the value reconfigurationFailure ;

2>else if the re-establishment procedure was initiated due to reconfiguration with sync failure as specified in 5.3.5.8.3 (intra-NR handover failure) or 5.4.3.5 (inter-RAT mobility from NR failure):

3>set the reestablishmentCause to the value handover Failure,

2> else:

3>set the reestablishmentCause to the value otherFailure

*** End text from 3GPP TS 38.331 ***

On the other hand, the UE also performs re-establishment when a UE is configured with a CHO (or other mobility operation) and receives an RRCReconfiguration message having portions with which the UE is unable to comply. This is illustrated in Figure 11, which shows a signaling procedure between a UE (1110), a first node (1120) serving a first cell that is a source cell for the UE, and a second node (1130) serving a second cell that is candidate target cell for CHO (or other relevant mobility operation). The first and second nodes may also be referred to as source and target nodes, respectively. For example, the source and target nodes can be RAN nodes such as eNBs, ng-eNBs, gNBs, and/or gNB components such as CUs and/or DUs. After determining that it is unable to comply with the RRCReconfiguration message, the UE selects the second cell during a cell reselection procedure and determines that the second cell is a candidate target cell associated with a conditional reconfiguration previously received from the first node and stored by the UE. Based on this determination, the UE sends a RRCReconfigurationComplete message instead of the RRCRestablishmentRequest message that is typically sent after a UE reestablishes an RRC connection after a failed reconfiguration.

In this scenario, however, the network does not learn that the UE is unable to comply with the RRCReconfiguration message from the first node via the first (source) cell. This lack of information can lead to misunderstanding by the network side of the conditions associated with the UE’s failure in the first (source) cell and reestablishment in the second (candidate target) cell. This misunderstanding can result in failures to address and/or correct the reasons why the UE was unable to comply with the RRCReconfiguration message.

Accordingly, embodiments of the present disclosure address these and other problems, issues, and/or difficulties by techniques whereby a UE that executes a stored conditional reconfiguration for a candidate target cell as part of a reestablishment procedure in the candidate target cell, can indicate (e.g., in an RRCReconfigurationComplete message) that the UE applied the stored conditional reconfiguration after receiving & RRCReconfiguration message (or similar message, such as RRCConnectionReconfiguration for LTE) with which the UE was unable to comply. This provides at least the advantage that the network node serving the source cell in which the UE received the message with which the UE was unable to comply (e.g., first node in Figure 11), is made aware of the problematic message and thus can correct the construction of such messages sent to other UEs in the future. Furthermore, in case the problem concerns the conditional reconfiguration of the candidate target cell, the network node can inform another network node that prepared the conditional reconfiguration about the problem, thereby facilitating similar correction by the other network node.

The operation of a UE in various embodiments is described as follows. In a first operation, the UE can receive first reconfiguration information from a first node serving a first cell in the wireless network. The first node can also be referred to as the source node for the UE, and the first cell can be referred to as the UE’s source cell. The first configuration information can include all or relevant parts of a reconfiguration message (e.g., RRCReconfiguration). In particular, the first reconfiguration information can include one or more conditional reconfigurations associated with respective one or more candidate target cells. The UE can store the one or more conditional reconfigurations. In some cases, the UE can start monitoring for the measurement conditions included in the conditional reconfigurations, such as illustrated in Figure 10 above. In some cases, the UE can receive second reconfiguration information from the first node, such as all or relevant parts of one or more reconfiguration messages.

Subsequently, the UE can determine that it is unable to comply with first reconfiguration information and/or the second reconfiguration information (if received). This can include, for example, attempting to apply a problematic portion of the information, such as one of the conditional reconfigurations in the first reconfiguration information. In some embodiments, the UE can revert to a configuration (e.g., an RRC configuration) in use before attempting to apply the problematic portion of the received information.

Based on determining that it is unable to comply with the first reconfiguration information and/or the second reconfiguration information, the UE performs a cell reselection procedure. In some embodiments, the UE operates in a connected state towards the wireless network (e.g., RRC CONNECTED mode) when it received the first reconfiguration information, and transitions to a non-connected state (e.g., RRC IDLE) before performing the cell reselection procedure.

During the cell reselection procedure, the UE selects a second cell served by a second node of the wireless network (e.g., based on measurements of the second cell satisfying one or more criteria). The UE then determines that the second cell is one of the candidate target cells associated with the stored conditional reconfigurations received in the first reconfiguration information. Based on this determination, the UE applies the stored conditional reconfiguration associated with the second cell and sends the second node (i.e., that serves the second cell) a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the first reconfiguration information and/or the second reconfiguration information.

In some embodiments, the indication can include a flag that indicates the UE was unable to comply with an RRCReconfiguration message. An exemplary flag can be called “RRCConfigCompliancelssue” or a similar name.

In some specific embodiments, the indication can include identifiers of one or more cell associated with an RRCReconfiguration message with which the UE was unable to comply (i.e., the problematic reconfiguration message). For example, a conditional reconfiguration for a candidate target cell can be received as an RRCReconfiguration message prepared by the node serving the candidate target cell (e.g., second node in Figure 11). This RRCReconfiguration message (referred as “embedded RRCReconfiguration”) is embedded within another RRCReconfiguration message (referred to as ‘encapsulating RRCReconfiguration’) prepared and sent by the node serving the UE’s source cell (e.g., first node in Figure 11).

This is illustrated by the exemplary ASN.l data structure shown in Figure 12. The encapsulating RRCReconfiguration is a top-level RRCReconfiguration-vl610-IEs data structure, while the embedded RRCReconfiguration is the condRRCReconfig-rl6 information element (IE) within that top-level data structure.

The problematic portion can be in the encapsulating RRCReconfiguration itself, or it can be in the embedded RRCReconfiguration prepared by the node serving the candidate target cell. The UE can indicate the source of the problem in various ways, described below.

In some embodiments, when the UE is unable to comply with the embedded RRCReconfiguration, the UE can include a cell identifier and a frequency identifier associated with the candidate target cell (e.g., SpCell) in the embedded RRCReconfiguration. For example, these fields can be the physCellld and the absoluteFrequencySSB fields, respectively, of the spCellConfigCommon portion of the reconfigurationWithSync IE in the embedded RRCReconfiguration. In the context of the indication in the first message, these fields can be called failedRRCConfigTargetCelllD and failedRRCConfigTargetCellFreq , respectively, or similar names.

In some embodiments, when the UE is unable to comply with the embedded RRCReconfiguration, the UE can also include a globally unique identifier of the source cell from which the encapsulating RRCReconfiguration was received. This identifier can be called failedRRCConfigSourceCelllD or a similar name. This additional identifier can aid the receiving node in determining the cause of the UE non-compliance.

In some embodiments, when the UE is unable to comply with the encapsulating RRCReconfiguration, the UE can include the globally unique identifier of the source cell from which the encapsulating RRCReconfiguration was received (e.g., failedRRCConfigSource CelllD. When the UE includes failedRRCConfigSourceCelllD but not failedRRCConfigTargetCelllD , the receiving node can infer that the UE had the compliance problems with the encapsulating RRCReconfiguration. On the other hand, when the UE includes both failedRRCConfigSourceCelllD and failedRRCConfigTargetCelllD , the receiving node can infer that the UE had compliance problems with both the encapsulating RRCReconfiguration and the embedded RRCReconfiguration.

In some embodiments, the indication can include identifiers of one or more portions of the RRCReconfiguration message with which the UE was unable to comply (i.e., the problematic portion(s)).

Note that the indication can include any combination of the contents described above.

In some embodiments, the first message including the indication can be an RRCReconfigurationComplete message. Figure 13 shows an exemplary ASN.l data structure for an RRCReconfigurationComplete message according to these embodiments. In particular, the ASN.l data structure shown in Figure 13 includes an RRCReconfigurationComplete-vl6xx-IEs field that includes an optional rrcConfigComplianceIssue-rl6 sub-field. When present, this sub field has a value of “true”, indicating that the UE was unable to comply with a received RRCReconfiguration message and applied a stored conditional reconfiguration.

Skilled persons will recognize that the RRCReconfigurationComplete-vl6xx-IEs field shown in Figure 13 can be modified to carry other indication types and/or components discussed above, such as failedRRCConfigSourceCelllD , failedRRCConfigTargetCelllD , iailedRRCConfigTargetCell-Freq, etc. Furthermore, the exemplary ASN.1 data structure shown in Figure 13 (including any such modifications) can be included in a 3 GPP specification, such as 3 GPP TS 38.331 for NR RRC protocol.

In other embodiments, the first message can be a successful handover report or a message including a successful handover report. In some of these embodiments, the network can explicitly configure the UE to store potential successful handover reports indicating that the UE experienced compliance problems with an RRCReconfiguration message (or portion thereof) while being configured with a conditional RRCReconfiguration message. In other of these embodiments, the UE can autonomously store (i.e., without network command/request) successful handover reports that include such an indication.

In some embodiments, rather than including the indication that the UE experienced compliance problems with an RRCReconfiguration message while being configured with a conditional RRCReconfiguration message in an RRCReconfigurationComplete message, the UE can include in the RRCReconfigurationComplete message to the second node a further indication that a successful handover report is available to provide to the second node. Upon receiving such an indication, the second node can send a UEInformationRe quest message including a request to send the successful handover report, and the UE can respond with a UEInformationResponse message including the stored successful handover report with the indication.

Upon receiving the first message from the UE, the second node can identify the first node based on an identifier of the source cell (e.g., failedRRCConfigSourceCelllD discussed above) that is included as (or as part of) the indication in the first message. This identifier can be a globally unique identifier from which the second node can determine an association with the first node, i.e., the node serving the source cell in which the UE received the conditional reconfiguration. The second node can then send the first node a second message (e.g., a report) including the indication.

Upon receiving the report, the first node determines whether the report contains an identifier of a target cell {e.g., failedRRCConfigTargetCelllD mentioned above) associated with the reconfiguration information that was problematic for the UE and an identifier of a frequency associated with the target cell {e.g.,failedRRCConfigTargetCellFreq mentioned above). If these two identifiers are included, the first node identifies a further node that serves the target cell based on these two identifiers, and forwards the report to the identified further node. For example, the two identifiers can be mapped uniquely to the further node in the first node’s neighbor relation table.

Based on the received information, the further node responsible for generating reconfiguration information (e.g., RRCReconfiguration message) that was problematic for the UE can adapt contents of future reconfiguration information (e.g., RRCReconfiguration messages) sent to other UEs.

The embodiments described above can be further illustrated by Figures 14-16, which show exemplary methods (e.g., procedures) for a UE, a first node in a wireless network, and a second node in a wireless network, respectively. In other words, various features of operations described below correspond to various embodiments described above. The exemplary methods illustrated by Figures 14-16 can be used cooperatively to provide various exemplary benefits and/or advantages. Although Figures 14-16 show specific blocks in particular orders, the operations of the respective methods can be performed in different orders than shown and can be combined and/or divided into blocks having different functionality than shown. Optional blocks or operations are indicated by dashed lines.

In particular, Figure 14 shows a flow diagram of an exemplary method (e.g., procedure) for a UE configured to operate in a wireless network, according to various embodiments of the present disclosure. The exemplary method can be performed by a UE (e.g., wireless device, IoT device, modem, etc. or component thereof) such as described elsewhere herein.

The exemplary method can include operations of block 1420, where the UE can store first reconfiguration information received from a first node serving a first cell in the wireless network. The first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells. The exemplary method can also include operations of block 1450, where the UE can perform a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information (e.g., in block 1430).

The exemplary method can also include operations of block 1460, where based on determining that the second cell is one of the candidate target cells, the UE can apply the stored conditional reconfiguration associated with the second cell. The exemplary method can also include operations of block 1490, where the UE can send, to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one information.

In some embodiments, the UE is operating in a connected state (e.g., RRC CONNECTED) when receiving the first reconfiguration information and the exemplary method can also include operations of block 1440, where before performing the cell reselection procedure, the UE can transition to a non-connected state based on determining that the UE cannot comply with the at least one information.

In some embodiments, the first message is an RRCReconfigurationComplete message. An example of these embodiments is shown in Figure 13.

In other embodiments, the exemplary method can also include the operations of blocks 1465-1480. In block 1465, the UE can store the first message in a successful handover report based on successfully applying the conditional reconfiguration associated with the second cell. In block 1470, the UE can send, to the second node, a further indication that the successful handover report is available. In block 1480, the UE can receive, from the second node, a first request for the successful handover report. The first message is sent (e.g., in block 1490) in response to the first request.

In some of these embodiments, the further indication is sent in an RRCReconfigurationComplete message, the first request is included in a UEInformationRe quest message, and the first message is a UEInformationRe sponse message. In some of these embodiments, the exemplary method can also include the operations of block 1410, where the UE can receive, from the first node, a second request to store successful handover reports. The first message is stored (e.g., in block 1460) based on the second request.

In some embodiments, the indication (e.g., sent in block 1490) can include one or more of the following: a flag (e.g., as shown in Figure 13), an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with:

• an identifier of a target cell,

• an identifier of a frequency used in the target cell, and

• an identifier of a portion of the information that the UE was unable to comply with.

In some of these embodiments, when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell. In some of these embodiments, when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following: • the identifier of the candidate target cell associated with the particular conditional reconfiguration, and

• the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

In some of these embodiments, when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

In addition, Figure 15 shows a flow diagram of an exemplary method (e.g., procedure) for a first node configured to serve a first cell in a wireless network, according to various embodiments of the present disclosure. The exemplary method can be performed by a RAN node (e.g., base station, eNB, gNB, ng-eNB, etc. or component thereof) such as described elsewhere herein.

The exemplary method can include the operations of block 1520, where the first node can send, to a UE, first reconfiguration information that includes one or more conditional reconfigurations associated with respective one or more candidate target cells. The exemplary method can also include the operations of block 1540, where the first node can receive, from a second node serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information.

In some embodiments, the exemplary method can also include the operations of block 1530, where the first node can send the UE second reconfiguration information, such as a reconfiguration message the UE is unable to comply with (as mentioned above).

In some embodiments, the UE is operating in a connected state (e.g., RRC CONNECTED) when the first reconfiguration information is sent. In some embodiments, the exemplary method can also include the operations of block 1510, where the first node can send, to the UE, a second request to store successful handover reports. The second message is received (e.g., in block 1540) based on the second request.

In some embodiments, the indication (e.g., received in block 1540) can include one or more of the following: a flag (e.g., as shown in Figure 13), an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with:

• an identifier of a target cell,

• an identifier of a frequency used in the target cell, and

• an identifier of a portion of the information that the UE was unable to comply with. In some of these embodiments, when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell. In some of these embodiments, when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following:

• the identifier of the candidate target cell associated with the particular conditional reconfiguration, and

• the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

In some of these embodiments, when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

In some of these embodiments, the exemplary method can also include the operations of blocks 1550-1560, where the first node can determine a further node serving the candidate target cell based on the identifier of the candidate target cell and the identifier of the frequency used in the candidate target cell, and send the indication to the further node.

In addition, Figure 16 shows a flow diagram of an exemplary method (e.g., procedure) for a second node configured to serve a second cell in a wireless network, according to various embodiments of the present disclosure. The exemplary method can be performed by a RAN node (e.g., base station, eNB, gNB, ng-eNB, etc. or component thereof) such as described elsewhere herein.

The exemplary method can include the operations of block 1630, where the second node can receive, from a UE, a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information:

• first reconfiguration information received by the UE from a first node serving a first cell, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and

• second reconfiguration information received by the UE from the first node after the first reconfiguration information.

In some embodiments, the exemplary method can also include the operations of block 1640, where the second node can send, to the first node, a second message including the indication received in the first message. In some embodiments, the first message is an RRCReconfigurationComplete message. An example of these embodiments is shown in Figure 13.

In other embodiments, the exemplary method can also include the operations of blocks 1610-1620, where the second node can receive, from the UE, a further indication that a successful handover report is available; and send, to the UE, a first request for the successful handover report. The first message can be received (e.g., in block 1630) based on the first request. In some of these embodiments, the further indication is sent in an RRCReconfigurationComplete message, the first request is included in a UEInformationRe quest message, and the first message is a UEInformationResponse message.

In some embodiments, the indication (e.g., received in block 1630) can include one or more of the following: a flag (e.g., as shown in Figure 13), an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with:

• an identifier of a target cell,

• an identifier of a frequency used in the target cell, and

• an identifier of a portion of the information that the UE was unable to comply with.

In some of these embodiments, when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell. In some of these embodiments, when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following:

• the identifier of the candidate target cell associated with the particular conditional reconfiguration, and

• the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

In some of these embodiments, when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

Although various embodiments are described herein above in terms of methods, apparatus, devices, computer-readable medium and receivers, the person of ordinary skill will readily comprehend that such methods can be embodied by various combinations of hardware and software in various systems, communication devices, computing devices, control devices, apparatuses, non-transitory computer-readable media, etc.

Figure 17 shows an example of a communication system 1700 in accordance with some embodiments. In this example, the communication system 1700 includes a telecommunication network 1702 that includes an access network 1704, such as a radio access network (RAN), and a core network 1706, which includes one or more core network nodes 1708. The access network 1704 includes one or more access network nodes, such as network nodes 1710a and 1710b (one or more of which may be generally referred to as network nodes 1710), or any other similar 3 GPP access node or non-3GPP access point. The network nodes 1710 facilitate direct or indirect connection of UEs, such as by connecting UEs 1712a, 1712b, 1712c, and 1712d (one or more of which may be generally referred to as UEs 1712) to the core network 1706 over one or more wireless connections.

Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 1700 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system 1700 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

The UEs 1712 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 1710 and other communication devices. Similarly, the network nodes 1710 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1712 and/or with other network nodes or equipment in the telecommunication network 1702 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 1702.

In the depicted example, the core network 1706 connects the network nodes 1710 to one or more hosts, such as host 1716. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 1706 includes one more core network nodes (e.g., core network node 1708) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1708. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF).

The host 1716 may be under the ownership or control of a service provider other than an operator or provider of the access network 1704 and/or the telecommunication network 1702, and may be operated by the service provider or on behalf of the service provider. The host 1716 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio/video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

As a whole, the communication system 1700 of Figure 17 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

In some examples, the telecommunication network 1702 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1702 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1702. For example, the telecommunications network 1702 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and/or Massive Machine Type Communication (mMTC)/Massive IoT services to yet further UEs.

In some examples, the UEs 1712 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 1704 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1704. Additionally, a UE may be configured for operating in single- or multi -RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e., being configured for multi -radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

In the example, the hub 1714 communicates with the access network 1704 to facilitate indirect communication between one or more UEs (e.g., UE 1712c and/or 1712d) and network nodes (e.g., network node 1710b). In some examples, the hub 1714 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1714 may be a broadband router enabling access to the core network 1706 for the UEs. As another example, the hub 1714 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 1710, or by executable code, script, process, or other instructions in the hub 1714. As another example, the hub 1714 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 1714 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1714 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1714 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 1714 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy IoT devices.

The hub 1714 may have a constant/persistent or intermittent connection to the network node 1710b. The hub 1714 may also allow for a different communication scheme and/or schedule between the hub 1714 and UEs (e.g., UE 1712c and/or 1712d), and between the hub 1714 and the core network 1706. In other examples, the hub 1714 is connected to the core network 1706 and/or one or more UEs via a wired connection. Moreover, the hub 1714 may be configured to connect to an M2M service provider over the access network 1704 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1710 while still connected via the hub 1714 via a wired or wireless connection. In some embodiments, the hub 1714 may be a dedicated hub - that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 1710b. In other embodiments, the hub 1714 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1710b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.

Figure 18 shows a UE 1800 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3 GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.

A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a 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 may 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 may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

The UE 1800 includes processing circuitry 1802 that is operatively coupled via a bus 1804 to an input/output interface 1806, a power source 1808, a memory 1810, a communication interface 1812, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 18. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

The processing circuitry 1802 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1810. The processing circuitry 1802 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field- programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, 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 1802 may include multiple central processing units (CPUs).

In the example, the input/output interface 1806 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include 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. An input device may allow a user to capture information into the UE 1800. Examples of an input device 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 may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

In some embodiments, the power source 1808 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 1808 may further include power circuitry for delivering power from the power source 1808 itself, and/or an external power source, to the various parts of the UE 1800 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1808. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1808 to make the power suitable for the respective components of the UE 1800 to which power is supplied.

The memory 1810 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1810 includes one or more application programs 1814, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1816. The memory 1810 may store, for use by the UE 1800, any of a variety of various operating systems or combinations of operating systems.

The memory 1810 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), 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 tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and/or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 1810 may allow the UE 1800 to access instructions, application programs and 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 may be tangibly embodied as or in the memory 1810, which may be or comprise a device-readable storage medium.

The processing circuitry 1802 may be configured to communicate with an access network or other network using the communication interface 1812. The communication interface 1812 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1822. The communication interface 1812 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 1818 and/or a receiver 1820 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1818 and receiver 1820 may be coupled to one or more antennas (e.g., antenna 1822) and may share circuit components, software or firmware, or alternatively be implemented separately.

In the illustrated embodiment, communication functions of the communication interface 1812 may include cellular communication, Wi-Fi communication, LPWAN communication, 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. Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/internet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1812, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., an alert is sent when moisture is detected), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

A UE, when in the form of an Internet of Things (IoT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an IoT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an IoT device comprises circuitry and/or software in dependence of the intended application of the IoT device in addition to other components as described in relation to the UE 1800 shown in Figure 18.

As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g., by controlling an actuator) to increase or decrease the drone’s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

Figure 19 shows a network node 1900 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication 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 NRNodeBs (gNBs)).

Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may 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 may also be referred to as nodes in a distributed antenna system (DAS).

Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSRBSs, 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), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).

The network node 1900 includes a processing circuitry 1902, a memory 1904, a communication interface 1906, and a power source 1908. The network node 1900 may 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 may each have their own respective components. In certain scenarios in which the network node 1900 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 1900 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 1904 for different RATs) and some components may be reused (e.g., a same antenna 1910 may be shared by different RATs). The network node 1900 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1900, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 1900.

The processing circuitry 1902 may 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 1900 components, such as the memory 1904, to provide network node 1900 functionality.

In some embodiments, the processing circuitry 1902 includes a system on a chip (SOC). In some embodiments, the processing circuitry 1902 includes one or more of radio frequency (RF) transceiver circuitry 1912 and baseband processing circuitry 1914. In some embodiments, the radio frequency (RF) transceiver circuitry 1912 and the baseband processing circuitry 1914 may 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 1912 and baseband processing circuitry 1914 may be on the same chip or set of chips, boards, or units.

The memory 1904 may 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 may be used by the processing circuitry 1902. The memory 1904 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions (collectively denoted computer program product 1904a) capable of being executed by the processing circuitry 1902 and utilized by the network node 1900. The memory 1904 may be used to store any calculations made by the processing circuitry 1902 and/or any data received via the communication interface 1906. In some embodiments, the processing circuitry 1902 and memory 1904 is integrated.

The communication interface 1906 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 1906 comprises port(s)/terminal(s) 1916 to send and receive data, for example to and from a network over a wired connection. The communication interface 1906 also includes radio front-end circuitry 1918 that may be coupled to, or in certain embodiments a part of, the antenna 1910. Radio front-end circuitry 1918 comprises filters 1920 and amplifiers 1922. The radio front-end circuitry 1918 may be connected to an antenna 1910 and processing circuitry 1902. The radio front-end circuitry may be configured to condition signals communicated between antenna 1910 and processing circuitry 1902. The radio front-end circuitry 1918 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front- end circuitry 1918 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1920 and/or amplifiers 1922. The radio signal may then be transmitted via the antenna 1910. Similarly, when receiving data, the antenna 1910 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1918. The digital data may be passed to the processing circuitry 1902. In other embodiments, the communication interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, the network node 1900 does not include separate radio front-end circuitry 1918, instead, the processing circuitry 1902 includes radio front-end circuitry and is connected to the antenna 1910. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1912 is part of the communication interface 1906. In still other embodiments, the communication interface 1906 includes one or more ports or terminals 1916, the radio front- end circuitry 1918, and the RF transceiver circuitry 1912, as part of a radio unit (not shown), and the communication interface 1906 communicates with the baseband processing circuitry 1914, which is part of a digital unit (not shown).

The antenna 1910 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 1910 may be coupled to the radio front-end circuitry 1918 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 1910 is separate from the network node 1900 and connectable to the network node 1900 through an interface or port.

The antenna 1910, communication interface 1906, and/or the processing circuitry 1902 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna 1910, the communication interface 1906, and/or the processing circuitry 1902 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.

The power source 1908 provides power to the various components of network node 1900 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 1908 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1900 with power for performing the functionality described herein. For example, the network node 1900 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1908. As a further example, the power source 1908 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

Embodiments of the network node 1900 may include additional components beyond those shown in Figure 19 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, the network node 1900 may include user interface equipment to allow input of information into the network node 1900 and to allow output of information from the network node 1900. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1900.

Figure 20 is a block diagram of a host 2000, which may be an embodiment of the host 1716 of Figure 17, in accordance with various aspects described herein. As used herein, the host 2000 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 2000 may provide one or more services to one or more UEs.

The host 2000 includes processing circuitry 2002 that is operatively coupled via a bus 2004 to an input/output interface 2006, a network interface 2008, a power source 2010, and a memory 2012. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 18 and 19, such that the descriptions thereof are generally applicable to the corresponding components of host 2000. The memory 2012 may include one or more computer programs including one or more host application programs 2014 and data 2016, which may include user data, e.g., data generated by a UE for the host 2000 or data generated by the host 2000 for a UE. Embodiments of the host 2000 may utilize only a subset or all of the components shown. The host application programs 2014 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 2014 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 2000 may select and/or indicate a different host for over-the-top services for a UE. The host application programs 2014 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.

Figure 21 is a block diagram illustrating a virtualization environment 2100 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, 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. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 2100 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized.

Applications 2102 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.

Hardware 2104 includes processing circuitry, memory that stores software and/or instructions (denoted computer program product 2104a) executable by hardware processing circuitry, and/or other hardware devices as described herein, such as communication interface circuitry, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 2106 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 2108a and 2108b (one or more of which may be generally referred to as VMs 2108), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer 2106 may present a virtual operating platform that appears as networking hardware to VMs 2108.

VMs 2108 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 2106. Different embodiments of the instance of a virtual appliance 2102 may be implemented on one or more of VMs 2108, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may 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, a VM 2108 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 2108, and that part of hardware 2104 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 2108 on top of the hardware 2104 and corresponds to the application 2102.

Hardware 2104 may be implemented in a standalone network node with generic or specific components. Hardware 2104 may implement some functions via virtualization. Alternatively, hardware 2104 may be part of a larger cluster of hardware (e.g., a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 2110, which oversees lifecycle management of applications 2102. In some embodiments, hardware 2104 can include communication interface circuitry such as radio units that include one or more transmitters and one or more receivers that may be coupled to one or more antennas. The radio units may communicate directly with other hardware nodes (and/or UEs) via appropriate network interface(s). For example, the radio units can be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node, base station, gNB, etc. In some embodiments, some signaling can be provided with the use of a control system 2112 which may alternatively be used for communication between hardware nodes and radio units.

Figure 22 shows a communication diagram of a host 2202 communicating via a network node 2204 with a UE 2206 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1712a of Figure 17 and/or UE 1800 of Figure 18), network node (such as network node 1710a of Figure 17 and/or network node 1900 of Figure 19), and host (such as host 1716 of Figure 17 and/or host 2000 of Figure 20) discussed in the preceding paragraphs will now be described with reference to Figure 22.

Like host 2000, embodiments of host 2202 include hardware, such as a communication interface, processing circuitry, and memory. The host 2202 also includes software, which is stored in or accessible by the host 2202 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the TIE 2206 connecting via an over-the-top (OTT) connection 2250 extending between the TIE 2206 and host 2202. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 2250.

The network node 2204 includes hardware enabling it to communicate with the host 2202 and UE 2206. The connection 2260 may be direct or pass through a core network (like core network 1706 of Figure 17) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

The UE 2206 includes hardware and software, which is stored in or accessible by UE 2206 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 2206 with the support of the host 2202. In the host 2202, an executing host application may communicate with the executing client application via the OTT connection 2250 terminating at the UE 2206 and host 2202. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 2250 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 2250.

The OTT connection 2250 may extend via a connection 2260 between the host 2202 and the network node 2204 and via a wireless connection 2270 between the network node 2204 and the UE 2206 to provide the connection between the host 2202 and the UE 2206. The connection 2260 and wireless connection 2270, over which the OTT connection 2250 may be provided, have been drawn abstractly to illustrate the communication between the host 2202 and the UE 2206 via the network node 2204, without explicit reference to any intermediary devices and the precise routing of messages via these devices. As an example of transmitting data via the OTT connection 2250, in step 2208, the host 2202 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 2206. In other embodiments, the user data is associated with a UE 2206 that shares data with the host 2202 without explicit human interaction. In step 2210, the host 2202 initiates a transmission carrying the user data towards the UE 2206. The host 2202 may initiate the transmission responsive to a request transmitted by the UE 2206. The request may be caused by human interaction with the UE 2206 or by operation of the client application executing on the UE 2206. The transmission may pass via the network node 2204, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 2212, the network node 2204 transmits to the UE 2206 the user data that was carried in the transmission that the host 2202 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 2214, the UE 2206 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 2206 associated with the host application executed by the host 2202.

In some examples, the UE 2206 executes a client application which provides user data to the host 2202. The user data may be provided in reaction or response to the data received from the host 2202. Accordingly, in step 2216, the UE 2206 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE 2206. Regardless of the specific manner in which the user data was provided, the UE 2206 initiates, in step 2218, transmission of the user data towards the host 2202 via the network node 2204. In step 2220, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 2204 receives user data from the UE 2206 and initiates transmission of the received user data towards the host 2202. In step 2222, the host 2202 receives the user data carried in the transmission initiated by the UE 2206.

One or more of the various embodiments improve the performance of OTT services provided to the UE 2206 using the OTT connection 2250, in which the wireless connection 2270 forms the last segment. More precisely, the teachings of these embodiments can facilitate a network node, serving a source cell in which a UE received a reconfiguration message with which the UE was unable to comply, to be aware of the problematic message and rectify the construction of such messages sent to other UEs in the future. Furthermore, in case the problem concerns a conditional reconfiguration of a candidate target cell sent via the source cell, the network node can inform another network node that prepared the conditional reconfiguration about the problem, thereby facilitating similar rectification by the other network node. At a high level, this can increase reliability of UE and network operations for mobility, which makes OTT services delivered to UEs via the network more reliable. This improved reliability increases the value of such services to end users and service providers.

In an example scenario, factory status information may be collected and analyzed by the host 2202. As another example, the host 2202 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 2202 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 2202 may store surveillance video uploaded by a UE. As another example, the host 2202 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 2202 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and/or transmitting data.

In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 2250 between the host 2202 and UE 2206, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 2202 and/or UE 2206. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 2250 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2250 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 2204. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 2202. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2250 while monitoring propagation times, errors, etc.

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 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.

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.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

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. 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.

In addition, certain terms used in the present disclosure, including the specification and drawings, can be used synonymously in certain instances ( e.g “data” and “information”). It should be understood, that although these terms (and/or other terms that can be synonymous to one another) can be used synonymously herein, 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.

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

A1. A method for a user equipment (UE) configured to operate in a wireless network, the method comprising: storing a first reconfiguration message received from a first node serving a first cell in the wireless network, wherein the first reconfiguration message includes one or more conditional reconfigurations associated with respective one or more candidate target cells; performing a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following messages: the first reconfiguration message, and a second reconfiguration message subsequently received from the first node; and based on determining that the second cell is one of the candidate target cells, applying the stored conditional reconfiguration associated with the second cell; and sending, to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one message.

A2. The method of embodiment Al, wherein: the UE is operating in a connected state when receiving the first reconfiguration message; and the method further comprises, before performing the cell reselection procedure, transitioning to a non-connected state based on determining that the UE cannot comply with the at least one message.

A3. The method of any of embodiments A1-A2, wherein the first message is an RRCReconfigurationComplete message.

A4. The method of any of embodiments A1-A2, further comprising: based on successfully applying the conditional reconfiguration associated with the second cell, storing the first message as a successful handover report; sending, to the second node, a further indication that the successful handover report is available; and receiving, from the second node, a first request for the successful handover report, wherein the first message is sent in response to the first request.

A5. The method of embodiment A4, wherein: the further indication is sent in an RRCReconfigurationComplete message; the first request is included in a UEInformationRequest message; and the first message is a UEInformationResponse message.

A6. The method of any of embodiments A4-A5, further comprising receiving, from the first node, a second request to store successful handover reports, wherein the first message is stored based on the second request.

A7. The method of any of embodiments A1-A7, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one message that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a message portion that the UE was unable to comply with. A8. The method of embodiment A7, wherein when the UE was unable to comply with the first reconfiguration message, the indication includes the identifier of the first cell.

A9. The method of any of embodiments A7-A8, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration message, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

A10. The method of embodiment A9, wherein when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration message, the indication also includes the identifier of the first cell.

Bl. A method for a first node configured to serve a first cell in a wireless network, the method comprising: sending, to a user equipment (UE), a first reconfiguration message that includes one or more conditional reconfigurations associated with respective one or more candidate target cells; and receiving, from a second node serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following messages: the first reconfiguration message, and a second reconfiguration message subsequently received from the first node.

Bla. The method of embodiment Bl, further comprising sending, to the UE, a second reconfiguration message.

B2. The method of any of embodiments Bl-Bla, wherein the UE is operating in a connected state when the first reconfiguration message is sent. B3. The method of any of embodiments B1-B2, further comprising sending, to the UE, a second request to store successful handover reports, wherein the second message is received based on the second request.

B4. The method of any of embodiments B1-B3, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one message that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a message portion that the UE was unable to comply with.

B5. The method of embodiment B4, wherein when the UE was unable to comply with the first reconfiguration message, the indication includes the identifier of the first cell.

B6. The method of any of embodiments B4-B5, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration message, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

B7. The method of embodiment B6, further comprising: determining a further node serving the candidate target cell based on the identifier of the candidate target cell and the identifier of the frequency used in the candidate target cell; and sending the indication to the further node.

B8. The method of any of embodiment B6-B7, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration message, the indication also includes the identifier of the first cell. Cl . A method for a second node configured to serve a second cell in a wireless network, the method comprising: receiving, from a user equipment (UE), a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following messages: a first reconfiguration message received by the UE from a first node serving a first cell, wherein the first reconfiguration message includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and a second reconfiguration message subsequently received by the UE from the first node.

Cl a. The method of embodiment Cl, further comprising sending, to the first node, a second message including the indication received in the first message.

C2. The method of any of embodiments Cl -Cl a, wherein the first message is an RRCReconfigurationComplete message.

C3. The method of any of embodiments Cl -Cl a, further comprising: receiving, from the UE, a further indication that a successful handover report is available; and sending, to the UE, a first request for the successful handover report, wherein the first message is received in response to the first request.

C4. The method of embodiment C3, wherein: the further indication is received in an RRCReconfigurationComplete message; the first request is included in a UEInformationRequest message; and the first message is a UEInformationResponse message.

C5. The method of any of embodiments C1-C4, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one message that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a message portion that the UE was unable to comply with.

C6. The method of embodiment C5, wherein when the UE was unable to comply with the first reconfiguration message, the indication includes the identifier of the first cell.

C7. The method of any of embodiments C5-C6, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration message, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

C8. The method of any of embodiment C6-C7, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration message, the indication also includes the identifier of the first cell.

D1. A user equipment (UE) configured to operate in a wireless network, the UE comprising: communication interface circuitry configured to communicate with one or more nodes of the wireless network via one or more cells; and processing circuitry operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to perform operations corresponding to any of the methods of embodiments Al- A10.

D2. A user equipment (UE) configured to operate in a wireless network, the UE being further configured to perform operations corresponding to any of the methods of embodiments A1-A10.

D3. A non-transitory, computer-readable medium storing program instructions that, when executed by processing circuitry of a user equipment (UE) configured to operate in a wireless network, configure the UE to perform operations corresponding to any of the methods of embodiments A1-A10.

D4. A computer program product comprising program instructions that, when executed by processing circuitry of a user equipment (UE) configured to operate in a wireless network, configure the UE to perform operations corresponding to any of the methods of embodiments Al- A10.

El . A first node configured to serve a first cell in a wireless network, the first node comprising: communication interface circuitry configured to communicate with user equipment (UEs) via the first cell and with one or more further nodes of the wireless network; and processing circuitry operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to perform operations corresponding to any of the methods of embodiments B1-B8.

E2. A first node configured to serve a first cell in a wireless network, the first node being further configured to perform operations corresponding to any of the methods of embodiments B1-B8.

E3. A non-transitory, computer-readable medium storing program instructions that, when executed by processing circuitry of a first node configured to serve a first cell in a wireless network, configure the first node to perform operations corresponding to any of the methods of embodiments B1-B8.

E4. A computer program product comprising program instructions that, when executed by processing circuitry of a first node configured to serve a first cell in a wireless network, configure the first node to perform operations corresponding to any of the methods of embodiments B1-B8.

FI. A second node configured to serve a second cell in a wireless network, the second node comprising: communication interface circuitry configured to communicate with user equipment (UEs) via the second cell and with one or more further nodes of the wireless network; and processing circuitry operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to perform operations corresponding to any of the methods of embodiments C1-C8. F2. A second node configured to serve a second cell in a wireless network, the second node being further configured to perform operations corresponding to any of the methods of embodiments C1-C8.

F3. A non-transitory, computer-readable medium storing program instructions that, when executed by processing circuitry of a second node configured to serve a second cell in a wireless network, configure the second node to perform operations corresponding to any of the methods of embodiments C1-C8.

F4. A computer program product comprising program instructions that, when executed by processing circuitry of a second node configured to serve a second cell in a wireless network, configure the second node to perform operations corresponding to any of the methods of embodiments C1-C8.

Claims

1. A method for a user equipment, UE, configured to operate in a wireless network, the method comprising: storing (1420) first reconfiguration information received from a first node serving a first cell in the wireless network, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells; performing (1450) a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information; and based on determining that the second cell is one of the candidate target cells, applying

(1460) the stored conditional reconfiguration associated with the second cell; and sending (1490), to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one information.

2. The method of claim 1, wherein: the UE is operating in a connected state with the wireless network when receiving the first reconfiguration information; and the method further comprises, before performing (1450) the cell reselection procedure, transitioning (1440) to a non-connected state based on determining that the UE cannot comply with the at least one information.

3. The method of any of claims 1-2, wherein the first message is an RRCReconfigurationComplete message.

4. The method of any of claims 1-2, further comprising: based on successfully applying (1460) the conditional reconfiguration associated with the second cell, storing (1465) the first message in a successful handover report; sending (1470), to the second node, a further indication that the successful handover report is available; and receiving (1480), from the second node, a first request for the successful handover report, wherein sending (1490) the first message is responsive to the first request.

5. The method of claim 4, wherein: the further indication is sent in an RRCReconfigurationComplete message; the first request is included in a UEInformationRequest message; and the first message is a UEInformationResponse message.

6. The method of any of claims 4-5, further comprising receiving (1410), from the first node, a second request to store successful handover reports, wherein storing (1465) the first message is based on the second request.

7. The method of any of claims 1-7, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a portion of the information that the UE was unable to comply with.

8. The method of claim 7, wherein when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell.

9. The method of any of claims 7-8, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

10. The method of claim 9, wherein when the UE was unable to comply with one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

11. A method for a first node configured to serve a first cell in a wireless network, the method comprising: sending (1520), to a user equipment, UE, first reconfiguration information that includes one or more conditional reconfigurations associated with respective one or more candidate target cells; and receiving (1540), from a second node serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: the first reconfiguration information, and second reconfiguration information sent to the UE after the first reconfiguration information.

12. The method of claim 11, further comprising sending (1530) the second reconfiguration information to the UE.

13. The method of any of claims 11-12, wherein the UE is operating in a connected state with the wireless network when the first reconfiguration information is sent.

14. The method of any of claims 11-13, further comprising sending (1510), to the UE, a second request to store successful handover reports, wherein receiving (1540) the second message is based on the second request.

15. The method of any of claims 11-14, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a portion of the information that the UE was unable to comply with.

16. The method of claim 15, wherein when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell.

17. The method of any of claims 15-16, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

18. The method of claim 17, further comprising: determining (1550) a further node serving the candidate target cell based on the identifier of the candidate target cell and the identifier of the frequency used in the candidate target cell; and sending (1560) the indication to the further node.

19. The method of any of claim 17-18, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

20. A method for a second node configured to serve a second cell in a wireless network, the method comprising: receiving (1630), from a user equipment, UE, a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: first reconfiguration information received by the UE from a first node serving a first cell, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and second reconfiguration information received by the UE from the first node after the first reconfiguration information.

21. The method of claim 20, further comprising sending (1640), to the first node, a second message including the indication received in the first message.

22. The method of any of claims 20-21, wherein the first message is an RRCReconfigurationComplete message.

23. The method of any of claims 20-21, further comprising: receiving (1610), from the UE, a further indication that a successful handover report is available; and sending (1620), to the UE, a first request for the successful handover report, wherein receiving (1630) the first message is based on the first request.

24. The method of claim 23, wherein: the further indication is received in an RRCReconfigurationComplete message; the first request is included in a UEInformationRequest message; and the first message is a UEInformationResponse message.

25. The method of any of claims 20-24, wherein the indication comprises one or more of the following: a flag, an identifier of the first cell, and one or more of the following associated with the at least one information that the UE was unable to comply with: an identifier of a target cell, an identifier of a frequency used in the target cell, and an identifier of a portion of the information that the UE was unable to comply with.

26. The method of claim 25, wherein when the UE was unable to comply with the first reconfiguration information, the indication includes the identifier of the first cell.

27. The method of any of claims 25-26, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication includes the following: the identifier of the candidate target cell associated with the particular conditional reconfiguration, and the identifier of a frequency used in the candidate target cell associated with the particular conditional reconfiguration.

28. The method of claim 27, wherein when the UE was unable to comply with a particular one of the conditional reconfigurations included in the first reconfiguration information, the indication also includes the identifier of the first cell.

29. A user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206) configured to operate in a wireless network (599, 699, 799, 1704), the UE comprising: communication interface circuitry (1812) configured to communicate with one or more nodes (610, 620, 710, 720, 1020, 1030, 1120, 1130, 1710, 1900, 2102, 2204) of the wireless network via one or more cells; and processing circuitry (1802) operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to: store first reconfiguration information received from a first node serving a first cell in the wireless network, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells; perform a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information; and based on determining that the second cell is one of the candidate target cells, apply the stored conditional reconfiguration associated with the second cell; and send, to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one information.

30. The UE of claim 29, wherein the processing circuitry and the communication circuitry are further configured to perform operations corresponding to any of the methods of claims 2- 10

31. A user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206) configured to operate in a wireless network (599, 699, 799, 1704), the UE being further configured to: store first reconfiguration information received from a first node serving a first cell in the wireless network, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells; perform a cell reselection procedure to select a second cell served by a second node in the wireless network, based on determining that the UE cannot comply with at least one of the following information: the first reconfiguration information, and second reconfiguration information received from the first node after the first reconfiguration information; and based on determining that the second cell is one of the candidate target cells, apply the stored conditional reconfiguration associated with the second cell; and send, to the second node, a first message that includes an indication that the UE applied the stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one information.

32. The UE of claim 31, being further configured to perform operations corresponding to any of the methods of claims 2-10.

33. A non-transitory, computer-readable medium (1810) storing program instructions that, when executed by processing circuitry (1802) of a user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206) configured to operate in a wireless network (599, 699, 799, 1704), configure the UE to perform operations corresponding to any of the methods of claims 1-10.

34. A computer program product (1814) comprising program instructions that, when executed by processing circuitry (1802) of a user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206) configured to operate in a wireless network (599, 699, 799, 1704), configure the UE to perform operations corresponding to any of the methods of claims 1-10.

35. A first node (610, 620, 710, 720, 1020, 1120, 1710, 1900, 2102, 2204) configured to serve a first cell in a wireless network (599, 699, 799, 1704), the first node comprising: communication interface circuitry (1906, 2104) configured to communicate with user equipment, UEs (605, 705, 1010, 1110, 1712, 1800, 2206) via the first cell and with one or more further nodes (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) of the wireless network; and processing circuitry (1902, 2104) operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to: send, to a UE, first reconfiguration information that includes one or more conditional reconfigurations associated with respective one or more candidate target cells; and receive, from a second node serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: the first reconfiguration information, and second reconfiguration information sent to the UE after the first reconfiguration information.

36. The first node of claim 35, wherein the processing circuitry and the communication circuitry are further configured to perform operations corresponding to any of the methods of claims 12-19.

37. A first node (610, 620, 710, 720, 1020, 1120, 1710, 1900, 2102, 2204) configured to serve a first cell in a wireless network (599, 699, 799, 1704), the first node being further configured to: send, to a user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206), first reconfiguration information that includes one or more conditional reconfigurations associated with respective one or more candidate target cells; and receive, from a second node (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) serving a second cell that is one of the candidate target cells, a second message that includes an indication that the UE applied the conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: the first reconfiguration information, and second reconfiguration information sent to the UE after the first reconfiguration information.

38. The first node of claim 37, being further configured to perform operations corresponding to any of the methods of claims 12-19.

39. A non-transitory, computer-readable medium (1904, 2104) storing program instructions that, when executed by processing circuitry (1902, 2104) of a first node (610, 620, 710, 720, 1020, 1120, 1710, 1900, 2102, 2204) configured to serve a first cell in a wireless network (599, 699, 799, 1704), configure the first node to perform operations corresponding to any of the methods of claims 11-19.

40. A computer program product (1904a, 2104a) comprising program instructions that, when executed by processing circuitry (1902, 2104) of a first node (610, 620, 710, 720, 1020, 1120, 1710, 1900, 2102, 2204) configured to serve a first cell in a wireless network (599, 699, 799, 1704), configure the first node to perform operations corresponding to any of the methods of claims 11-19.

41. A second node (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) configured to serve a second cell in a wireless network (599, 699, 799, 1704), the second node comprising: communication interface circuitry (1906, 2104) configured to communicate with user equipment, UEs (605, 705, 1010, 1110, 1712, 1800, 2206) via the second cell and with one or more further nodes (610, 620, 710, 720, 1020, 1120, 1710, 1900,

2102, 2204) of the wireless network; and processing circuitry (1902, 2104) operably coupled to the communication interface circuitry, whereby the processing circuitry and the communication circuitry are configured to: receive, from a UE, a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: first reconfiguration information received by the UE from a first node serving a first cell, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and second reconfiguration information received by the UE from the first node after the first reconfiguration information.

42. The second node of claim 41, wherein the processing circuitry and the communication circuitry are further configured to perform operations corresponding to any of the methods of claims 21-28.

43. A second node (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) configured to serve a second cell in a wireless network (599, 699, 799, 1704), the second node being further configured to: receive, from a user equipment, UE (605, 705, 1010, 1110, 1712, 1800, 2206), a first message including an indication that the UE applied a stored conditional reconfiguration associated with the second cell when the UE was unable to comply with the at least one of the following information: first reconfiguration information received by the UE from a first node (610, 620, 710, 720, 1020, 1120, 1710, 1900, 2102, 2204) serving a first cell, wherein the first reconfiguration information includes one or more conditional reconfigurations associated with respective one or more candidate target cells, including the second cell; and second reconfiguration information received by the UE from the first node after the first reconfiguration information.

44. The second node of claim 43, being further configured to perform operations corresponding to any of the methods of claims 21-28.

45. A non-transitory, computer-readable medium (1904, 2104) storing program instructions that, when executed by processing circuitry (1902, 2104) of a second node (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) configured to serve a second cell in a wireless network (599, 699, 799, 1704), configure the second node to perform operations corresponding to any of the methods of claims 20-28.

46. A computer program product (1904a, 2104a) comprising program instructions that, when executed by processing circuitry (1902, 2104) of a second node (610, 620, 710, 720, 1030, 1130, 1710, 1900, 2102, 2204) configured to serve a second cell in a wireless network (599, 699, 799, 1704), configure the second node to perform operations corresponding to any of the methods of claims 20-28.