User equipment configured for pscell addition or change after handover

Abstract

A User Equipment (UE) configured for operation in a fifth-generation new radio (5G NR) network, may receive an RRC handover command when the UE is in a radio-resource control (RRC) connected state with a source primary cell (PCell) (Cell1). The UE may detect a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after receipt of the RRC handover command. In response to the RRC handover command, the UE may transmit a first physical random-access channel (PRACH) for handover to the target PCell within a first predetermined time period after receipt of the RRC handover command and transmit a second PRACH to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover command. More time may be allowed when the PSCell is transmitted within narrow bandwidth (e.g., a 12 PRB bandwidth)

Description

1884.R76WO1 AG9579-PCTUSER EQUIPMENT CONFIGURED FOR PSCELL ADDITION OR CHANGE AFTER HANDOVERPRIORITY CLAIMS

[0001] This application claims the benefit of priority to United States Provisional Patent Application Serial No. 63 / 779,128, filed March 27, 2025 [reference number AG5766-Z], and United States Provisional Patent Application Serial No. 63 / 779,596, filed March 28, 2025 [reference number AG5782-Z], which are incorporated herein by reference in their entireties.TECHNICAL FIELD

[0002] Embodiments pertain to wireless communications. Some embodiments relate to wireless networks including 3 GPP (Third Generation Partnership Project) and fifth-generation (5G) networks including 5G new radio (NR) (or 5G-NR) networks. Some embodiments relate to sixth-generation (6G) networks.BACKGROUND

[0003] Mobile communications have evolved significantly from early voice systems to today’s highly sophisticated integrated communication platform. With the increase in different types of devices communicating with various network devices, usage of 3GPP 5GNR systems has increased. The penetration of mobile devices (user equipment or UEs) in modem society has continued to drive demand for a wide variety of networked devices in many disparate environments. 5G NR wireless systems are forthcoming and are expected to enable even greater speed, connectivity, and usability, and are expected to increase throughput, coverage, and robustness and reduce latency and operational and capital expenditures. 5G-NR networks will continue to1884.R76WO1 AG9579-PCTevolve based on 3 GPP LTE- Advanced with additional potential new radio access technologies (RATs) to enrich people’s lives with seamless wireless connectivity solutions delivering fast, rich content and services. As current cellular network frequency is saturated, higher frequencies, such as millimeter wave (mmWave) frequency, can be beneficial due to their high bandwidth.

[0004] In 5GDual Connectivity (DC), a Primary Secondary Cell (PSCell) serve as an anchor cell of a Secondary Cell Group (SCG). When a UE is configured for dual connectivity, it maintains simultaneous connections to two nodes: a Master Node (for example, an LTE eNB in EN-DC) and a Secondary Node (for example, a 5G gNB). The PCell anchors the master connection, while the PSCell performs the equivalent role within the secondary node. One issue with PSCells is that prompt completion of random access on a target PSCell following receipt of a PCell handover command is important to maintain service continuity, preserve throughput, and ensure the coordinated reconfiguration completes as intended. Another issue with PSCells is the prompt transmission of measurement reports when a PSCell is deactivated.

[0005] Thus, there are general needs a UE is able to add or change a PSCell following handover in a timely manner. Thus, there are also needs for a UE is able to transmit measurement reports when a PSCell is deactivated in a timely manner.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 illustrates an architecture of a network, in accordance with some embodiments.

[0007] FIG. 2 illustrates a testing scenario, in accordance with some embodiments.

[0008] FIG. 3 illustrates a functional block diagram of a wireless communication device, in accordance with some embodiments.

[0009] FIG. 4 illustrates a procedure for verifying performance of a UE for adding or changing a target PSCell after receipt of an RRC handover command, in accordance with some embodiments.1884.R76WO1 AG9579-PCTDETAILED DESCRIPTION

[0010] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0011] Some embodiments are directed to a User Equipment (UE) configured for operation in a fifth-generation new radio (5G NR) network. In these embodiments, the UE may receive an RRC handover command when the UE is in a radio-resource control (RRC) connected state with a source primary cell (PCell) (Celli). In these embodiments, the UE may detect a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after receipt of the RRC handover command. In response to the RRC handover command, the UE may transmit a first physical random-access channel (PRACH) for handover to the target PCell within a first predetermined time period after receipt of the RRC handover command and transmit a second PRACH to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover command. In these embodiments, more time may be allowed when the PSCell is transmitted within narrow bandwidth.

[0012] Some embodiments are applicable to NR FR1-FR1 intrafrequency PCell handover and NR FR1-FR1 intra-frequency PSCell change where the target PSCell is configured with a 12 PRB SSB bandwidth.

[0013] Some embodiments relate to measurement reporting of a deactivated PSCell in NR-DC operation. In these embodiments, when the UE is in a radio-resource control (RRC) connected state with a primary cell (PCell) (Cell 1) where the PCell is a first serving cell, the UE may add a primary secondary cell (PSCell) (Cell 2) as a second serving cell for NR dual connectivity (NR DC) operation with the first serving cell. In these embodiments, the UE may transmit a measurement report within a predetermined period of time after a deactivation of the PSCell.1884.R76WO1 AG9579-PCT

[0014] Some of these embodiments are applicable to a testing scenario in which a system simulator is used to simulate the network. These embodiments, as well as others, are described in more detail herein.

[0015] FIG. 1 illustrates an architecture of a network in accordance with some embodiments. The network 140A is shown to include user equipment (UE) 101 and UE 102. The UE 101 and UE 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks) but may also include any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, drones, or any other computing device including a wired and / or wireless communications interface. TheUE 101 and UE 102 can be collectively referred to herein as UE 101, and UE 101 can be used to perform one or more of the techniques disclosed herein.

[0016] Any of the radio links described herein (e.g., as used in the network 140 A or any other illustrated network) may operate according to any exemplary radio communication technology and / or standard.

[0017] LTE and LTE- Advanced are standards for wireless communications of high-speed data for UE such as mobile telephones. In LTE-Advanced and various wireless systems, carrier aggregation is a technology according to which multiple carrier signals operating on different frequencies may be used to carry communications for a single UE, thus increasing the bandwidth available to a single device. In some embodiments, carrier aggregation may be used where one or more component carriers operate on unlicensed frequencies.

[0018] Embodiments described herein can be used in the context of any spectrum management scheme including, for example, dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared Access (LSA) in 2.3-2.4 GHz, 3.4-3.6 GHz, 3.6-3.8 GHz, and further frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and further frequencies).

[0019] Embodiments described herein can also be applied to different Single Carrier or OFDM flavors (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.) and in particular 3 GPP NR1884.R76WO1 AG9579-PCT(New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0020] In some embodiments, any of the UE 101 and UE 102 can comprise an Intemet-of-Things (loT) UE or a Cellular loT (CIoT) UE, which can comprise a network access layer designed for low-power loT applications utilizing short-lived UE connections. In some embodiments, any of the UE 101 and UE 102 can include a narrowband (NB) loT UE (e.g., such as an enhanced NB-IoT (eNB-IoT) UE and Further Enhanced (FeNB-IoT) UE). An loT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity -Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or loT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An loT network includes interconnecting loT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The loT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the loT network.

[0021] In some embodiments, any of the UE 101 and UE 102 can include enhanced MTC (eMTC) UEs or further enhanced MTC (FeMTC) UEs.

[0022] The UE 101 and UE 102 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 110. The RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UE 101 and UE 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution1884.R76WO1 AG9579-PCT(LTE) protocol, a fifth-generation (5G) protocol, a New Radio (NR) protocol, and the like.

[0023] In an aspect, the UE 101 and UE 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

[0024] The UE 102 is shown to be configured to access an access point (AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as, for example, a connection consistent with any IEEE 802.11 protocol, according to which the AP 106 can comprise a wireless fidelity (WiFi) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

[0025] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), Next Generation NodeBs (gNBs), RAN nodes, and the like, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some embodiments, the RAN nodes 111 and 112 can be transmission / reception points (TRPs). In instances when the RAN nodes 111 and 112 are NodeBs (e.g., eNBs or gNBs), one or more TRPs can function within the communication cell of the NodeBs. The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro-RAN node, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node.

[0026] Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UE 101 and UE 102. In some embodiments, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio1884.R76WO1 AG9579-PCTnetwork controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In an example, any of the RAN nodes 111 and / or 112 can be a new generation Node-B (gNB), an evolved node-B (eNB), or another type of RAN node.

[0027] The RAN 110 is shown to be communicatively coupled to a core network (CN) 120 via an SI interface 113. In embodiments, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN. In this aspect, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 111 and 112 and the serving gateway (S-GW) 122, and the SI -mobility management entity (MME) interface 115, which is a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

[0028] In this aspect, the CN 120 comprises the MMEs 121, the S-GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility embodiments in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing / roaming, authentication, authorization, naming / addressing resolution, location dependencies, etc.

[0029] The S-GW 122 may terminate the SI interface 113 towards the RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3 GPP mobility. Other responsibilities of the S-GW 122 may include a lawful intercept, charging, and some policy enforcement.1884.R76WO1 AG9579-PCT

[0030] The P-GW 123 may terminate an SGi interface toward a PDN. The P-GW 123 may route data packets between the CN 120 and external networks such as a network including the application server 184 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. The P-GW 123 can also communicate data to other external networks 131 A, which can include the Internet, IP multimedia subsystem (IPS) network, and other networks. Generally, the application server 184 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this aspect, the P-GW 123 is shown to be communicatively coupled to an application server 184 via an IP interface 125. The application server 184 can also be configured to support one or more communication services (e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UE 101 and UE 102 via the CN 120.

[0031] The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, in some embodiments, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with a local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 184 via the P-GW 123.

[0032] In some embodiments, the communication network 140 A can be an loT network or a 5G network, including 5G new radio network using communications in the licensed (5G NR) and the unlicensed (5G NR-U) spectrum. One of the current enablers of loT is the narrowband-IoT (NB-IoT).

[0033] An NG system architecture can include the RAN 110 and a 5G network core (5GC). In these embodiments, the RAN 110 can include a plurality of nodes, such as gNBs and NG-eNBs. The CN 120 (e.g., a 5G core network or 5GC) can include an access and mobility function (AMF) and / or a user plane1884.R76WO1 AG9579-PCTfunction (UPF). The AMF and the UPF can be communicatively coupled to the gNBs and the NG-eNBs via NG interfaces. More specifically, in some embodiments, the gNBs and the NG-eNBs can be connected to the AMF by NG-C interfaces, and to the UPF by NG-U interfaces. The gNBs and the NG-eNBs can be coupled to each other via Xn interfaces.

[0034] In some embodiments, the NG system architecture can use reference points between various nodes as provided by 3GPP Technical Specification (TS) 23.501 (e.g., V15.4.0, 2018-12). In some embodiments, each of the gNBs and the NG-eNBs can be implemented as a base station, a mobile edge server, a small cell, a home eNB, and so forth. In some embodiments, a gNB can be a master node (MN) and NG-eNB can be a secondary node (SN) in a 5G architecture. In some embodiments, any of the UEs or base stations described in connection with FIG. 1 can be configured to perform the functionalities described herein.

[0035] Rel-15 NR systems are designed to operate on the licensed spectrum. The NR-unlicensed (NR-U), a short-hand notation of the NR-based access to unlicensed spectrum, is a technology that enables the operation of NR systems on the unlicensed spectrum.

[0036] As mentioned above, in 5GDual Connectivity (DC), the Primary Secondary Cell (PSCell) serves as the anchor cell of the Secondary Cell Group (SCG). When a UE is configured for dual connectivity, it maintains simultaneous connections to two nodes: a Master Node (for example, an LTE eNB in EN-DC) and a Secondary Node (for example, a 5G gNB). The PCell anchors the master connection, while the PSCell performs the equivalent role within the secondary node. The PSCell differs from ordinary secondary cells by virtue of the additional functions it may perform. Unlike regular SCells, the PSCell can transmit and receive on the PUCCH, enabling independent uplink control signalling. It also serves as the timing and synchronization reference for the SCG, and it is the cell used to carry RRC signalling with the secondary node for SN-initiated procedures. Accordingly, the PSCell is not merely another serving cell; it is the radio anchor for the secondary-node connection.

[0037] A UE is assigned a PSCell when the network determines that dual connectivity is beneficial, typically when the UE has sufficient signal quality on1884.R76WO1 AG9579-PCTan NR cell to sustain a secondary link and can therefore realize additional throughput and / or capacity. The Master Node initiates the procedure by sending an SN Addition Request to the candidate secondary node, which responds with an SCG configuration. The UE then performs random access on the PSCell to establish uplink synchronization with the secondary node, after which the SCG becomes active.

[0038] A PSCell change is required when radio conditions evolve. For example, as the UE moves away from the current secondary node and PSCell radio quality degrades, or when a superior NR cell becomes available (either on the same node or on a different node), the network may trigger a PSCell change. In some cases, the Secondary Node itself is replaced, which entails releasing the existing PSCell and establishing a new one. Because uplink synchronization must be re-established on the target PSCell, the procedure includes random access on the new cell and is therefore closer in nature to a handover than to a routine SCell reconfiguration.

[0039] When a UE receives a handover command instructing it to move from a source PCell to a target PCell, it may have ongoing data flows that depend on the SCG remaining operational. If the UE is operating in dual connectivity at the time of handover, traffic may be split across the Master Cell Group (MCG) and the SCG, with the SCG potentially carrying a significant portion of the throughput. This creates a time-sensitive dependency between completion of the PCell handover and the state of the PSCell.

[0040] The handover command may include instructions to add or change the PSCell as part of the reconfiguration. This can occur, for example, when the target PCell is served by a different Master Node whose preferred Secondary Node differs from the current one, or when the post-handover topology renders the existing PSCell unsuitable or unreachable. Until the UE successfully completes random access on the target PSCell, the SCG cannot be considered operational under the new configuration. During this interval, the UE may be unable to use the secondary node for uplink or downlink transmission, effectively reverting to single connectivity and losing the capacity benefits provided by dual connectivity.1884.R76WO1 AG9579-PCT

[0041] In addition to throughput, there are implications for data continuity. Split bearers, for which PDCP packets are distributed across both the MCG and SCG, rely on both legs being available to deliver data efficiently. If PSCell establishment is significantly delayed after the PCell handover completes, packets routed toward the SCG leg may stall, increasing latency or requiring re-routing via the MCG alone. The MCG may be unable to absorb the full load without performance degradation.

[0042] A further consideration is synchronization timing. Following coordination between the Master Node and the Secondary Node, the network expects the UE to complete the SCG configuration within a defined timeframe. If the UE is slow to transmit PRACH on the target PSCell, the secondary node may not observe the expected access attempt, which can lead to configuration timeouts or to the SCG being released. In that case, a new SN Addition procedure may be required.

[0043] For these reasons, prompt completion of random access on the target PSCell following receipt of the PCell handover command is important to maintain service continuity, preserve throughput, and ensure the coordinated reconfiguration completes as intended.

[0044] When a PSCell is configured with a narrow bandwidth of 12 PRBs rather than a more typical 20 PRBs, PRACH configuration becomes more constrained. This can have practical implications for how quickly and reliably the UE completes the random access procedure required to establish or change the PSCell.

[0045] In NR, PRACH resources must be configured within the available carrier bandwidth. The PRACH occupies a defined frequency region, and the selected format and frequency-domain allocation must be compatible with the configured numerology and bandwidth. With only 12 PRBs available, there is less flexibility in PRACH placement, and some PRACH configurations that are feasible in a wider carrier may not be supportable. The network must therefore fit PRACH into a narrow allocation, which can restrict preamble-format choices and reduce the number of available PRACH occasions in the time domain.

[0046] A narrower bandwidth can also affect PRACH link budget and detection performance. Wider-bandwidth configurations may provide greater1884.R76WO1 AG9579-PCTfrequency diversity, which can improve preamble detection robustness. With 12 PRBs, the PRACH preamble has less opportunity to exploit frequency diversity, potentially increasing susceptibility to interference and adverse channel conditions. If the UE is near the edge of PSCell coverage (a plausible scenario, as the secondary node in dual connectivity deployments is often a small cell with limited range), reduced robustness can increase the probability of preamble detection failures, requiring retransmissions and increasing PSCell establishment latency.

[0047] PRACH occasion density is another factor. In wider-bandwidth cells, the network has more flexibility to schedule frequent PRACH occasions across time-frequency resources, reducing the waiting time before the UE can transmit a preamble. In a 12 PRB cell, the constrained bandwidth can limit scheduling flexibility, potentially reducing PRACH occasion frequency and increasing the time the UE must wait for an opportunity to initiate random access.

[0048] Collectively, these factors can make PSCell random access in a 12 PRB configuration more fragile, particularly given the time sensitivity of PSCell establishment during concurrent PCell handover. Restricted format choices, reduced detection robustness, and potentially sparser PRACH occasions can extend the time required to establish uplink synchronization with the secondary node. This increases the risk that the SCG will not become operational promptly, with corresponding impacts on data continuity and throughput.

[0049] 3 GPP TS 38.133 specifies requirements that bound the time within which a UE is expected to initiate PRACH transmission on a PSCell following receipt of a handover command. The applicable time bound depends on the target-cell configuration, and in particular on the PRACH configuration and the density of available PRACH occasions.

[0050] In dual connectivity, the UE does not maintain a purely passive association with the PSCell. It continues to measure radio conditions on the PSCell and, in many cases, on neighboring cells. These measurements, and the associated reporting, enable the network to manage the secondary connection over time.1884.R76WO1 AG9579-PCT

[0051] A primary objective of PSCell measurements is to monitor the quality of the secondary link. The UE measures metrics such as reference signal received power (RSRP) and reference signal received quality (RSRQ) on the PSCell, which characterize signal strength and quality (including the effective signal-to-interference-plus-noise ratio). When these measurements remain above configured thresholds, the network can infer that the PSCell is providing a stable and beneficial secondary connection. If measurements deteriorate, the network gains early indication of a weakening SCG prior to outright failure and can respond by triggering a PSCell change or releasing the SCG in a controlled manner.

[0052] In addition to monitoring the current PSCell, the UE is typically configured to measure neighboring cells on the same frequency and / or adjacent frequencies. This supports PSCell mobility. Analogous to PCell mobility decisions, the network uses measurements of candidate NR cells to determine when to move the UE’s PSCell to a different cell within the same secondary node or to a different secondary node. Without such measurements, PSCell changes would tend to be reactive (triggered by failures) rather than proactive (triggered by trends in improving or degrading radio conditions).

[0053] Measurement reports are transmitted to the Master Node, which coordinates the overall dual connectivity configuration. The Master Node uses these reports to manage the SCG (for example, retaining the current PSCell, changing the PSCell, adding or removing SCG SCells, or releasing the secondary node connection). Because the Master Node does not directly observe the UE’s radio environment on the secondary node’s frequencies, UE measurement reports are a primary input to these decisions.

[0054] Reporting is often event-triggered rather than purely periodic. In this model, the UE reports when specified conditions are met (for example, when a neighboring cell exceeds the current PSCell by a defined margin, or when the PSCell falls below a threshold), thereby providing timely and actionable information while limiting signaling overhead during stable conditions.

[0055] PSCell measurements also influence the execution time of PSCell changes during handover. If the UE has been measuring and has already identified a candidate PSCell prior to handover, then upon receipt of a handover1884.R76WO1 AG9579-PCTcommand that includes PSCell addition or change, the UE can proceed directly to PRACH transmission on the target PSCell without incurring additional cell search and identification delay. Conversely, if the UE has not been measuring (or has not successfully identified) the target PSCell in advance, it may need to perform these steps after receiving the command, adding latency to PSCell establishment. Accordingly, the continuity and quality of measurement activity directly affect how quickly a PSCell change can be completed when required by a handover event.

[0056] PSCell deactivation indicates that the UE is no longer actively transmitting or receiving data via the secondary node, and that certain processing associated with the SCG is suspended to reduce power consumption and processing load. Deactivation is distinct from release: the SCG configuration remains in place, the PSCell remains configured, and the network retains the option to use the secondary connection again when conditions warrant. This distinction is central to understanding why measurements and reporting may continue even when the PSCell is not carrying traffic.

[0057] From the network perspective, a deactivated PSCell is a resource that can typically be reactivated more quickly than re-establishing the SCG via a full SN Addition procedure. However, to make an appropriate reactivation decision, the network must determine whether the deactivated PSCell remains a suitable candidate. If the UE has moved or interference conditions have changed, the PSCell that was suitable at deactivation may no longer be optimal or may no longer be usable. Without continued measurement and reporting, the network would make reactivation decisions without current radio-environment visibility.

[0058] Accordingly, the UE may continue to measure the deactivated PSCell and report its quality to support network decision-making. If measurements indicate that signal quality remains adequate (or has improved), the network may trigger reactivation. If measurements indicate significant deterioration, the network may instead release the SCG and initiate a new SN Addition targeting a different, more suitable cell.

[0059] There is also a mobility aspect. Even while the PSCell is deactivated, the UE may continue to move. Reporting measurements for the deactivated PSCell alongside measurements for neighboring cells provides the1884.R76WO1 AG9579-PCTnetwork with a comparative view of the radio environment. If a report indicates that a neighboring NR cell is now significantly stronger than the deactivated PSCell, the network may reconfigure the SCG to use that neighbor as the new PSCell rather than reactivating the original cell. In this way, measurement reporting during deactivation directly supports PSCell mobility decisions coordinated by the Master Node.

[0060] Measurement continuity during deactivation is also relevant in handover scenarios. If the UE undergoes a PCell handover while the PSCell is deactivated, the target Master Node may need to decide promptly whether to reactivate the existing PSCell, change the PSCell, or release the SCG.Measurement reports generated during the deactivation interval provide the information required to make this decision without waiting for a new measurement cycle after handover. Given the time sensitivity of PSCell establishment during handover, having current measurement data available when the handover command is processed can materially reduce delays in restoring the secondary link.

[0061] Thus, the UE may transmit measurement reports for a deactivated PSCell because deactivation represents a suspension of user-plane activity rather than the end of the network’s interest in that cell. Effective SCG management, whether reactivating the same PSCell, selecting a better candidate, or releasing the secondary node, requires a current view of the radio environment, even when the PSCell is temporarily inactive.

[0062] A User Equipment (UE) configured for operation in a fifthgeneration new radio (5GNR) network may receive an RRC handover command when the UE is in a radio-resource control (RRC) connected state with a source primary cell (PCell) (Celli). In these embodiments, the UE may detect a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after receipt of the RRC handover command. In response to the RRC handover command, the UE may transmit a first physical random-access channel (PRACH) for handover to the target PCell within a first predetermined time period after receipt of the RRC handover command. In response to the RRC handover command, the UE may also transmit a second PRACH to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover1884.R76WO1 AG9579-PCTcommand. Some of these embodiments may be applicable to a testing scenario in which a system simulator is used to simulate the network.

[0063] In some embodiments, the RRC handover command may be for NR Dual Connectivity (NR-DC) Frequency Range 1 (FR1) to FR1 (NR-DC FR1-FR1) intra-frequency PCell handover and may indicate NR-DC FR1-FR1 intra-frequency PSCell addition or change at handover.

[0064] In some embodiments, synchronization signal blocks (SSBs) of the target PSCell are transmitted within a 3 MHz bandwidth or less comprising no more than twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in FR1. In these embodiments, the source PCell and the target PCell may have wider bandwidths than the target PSCell and the target PSCell may be configured for narrow bandwidth operation.

[0065] In some embodiments, the SSBs of the source PCell and SSBs of the target PCell are transmitted within a 10 MHz bandwidth comprising up to 20 PRBs with a subcarrier spacing of 15 kHz in FR1. In these embodiments, each PRB for SCS of 15 kHz may be 180 kHz, and the 12 PRB bandwidth of the PSCell would therefore be about 2.16 MHz, therefore within a 3 MHz bandwidth). In these embodiments, the SSB configuration for the target PScell may be SSB pattern 13 in FR1.

[0066] In some embodiments, the first predetermined time period may be 78 milliseconds (ms), and the second predetermined time period may be 178 ms.

[0067] In some embodiments, the target PCell and the target PSCell become detectable by the UE after receipt of the RRC handover command and are not detectable by the UE prior to receipt of the RRC handover command. In these conditional handover (CHO) embodiments, the UE may store the RRC handover command until the target PCell and the target PSCell become detectable. In some other embodiments, the target PCell and the target PSCell may be detectable by the UE prior to receipt of the RRC handover command, although the scope of the embodiments is not limited in this respect.

[0068] In some embodiments, in response to the RRC handover command, the UE may transmit the first PRACH handover to the target PCell within the first predetermined time period (e.g., 78ms) after a last transmission1884.R76WO1 AG9579-PCTtime interval (TTI) that contains the RRC handover command, and may transmit the second PRACH to add or change to the target PSCell within the second predetermined time period (e.g., 178ms) after the last TTI that contains the RRC handover command.

[0069] These embodiments may be applicable to NR FR1-FR1 intrafrequency PCell handover and NR FR1-FR1 intra-frequency PSCell change where the target PSCell is configured with a 12 PRB SSB bandwidth. These embodiments may verify the handover delay requirements in NR-DC (FR1-FR1) and PSCell addition / change delay requirements during handover with PSCell from NR-DC (FR1-FR1) to NR-DC (FR1-FR1).

[0070] In some embodiments, the last TTI comprises a last slot in which a physical downlink shared channel (PDSCH) carrying that RRC handover command is received by the UE, the RRC handover command comprising an RRC reconfiguration message. In some embodiments, the source PCell, the target PCell and the target PSCell are configured for frequency domain duplex (FDD) operation.

[0071] In some embodiments, in a testing scenario, the UE may be in the RRC connected state with the source PCell provided by a system simulator, the RRC handover command may be received from the system simulator. The target PCell and the target PSCell may be provided by the system simulator and the SSBs of the target PSCell are transmitted by the system simulator within the 3 MHz bandwidth comprising the 12 PRBs with the subcarrier spacing of 15 kHz in FR1.

[0072] These embodiments may verify the handover delay requirements and PSCell addition / change delay requirements in HO with PSCell from NR-DC (FR1-FR1) to NR-DC (FR1-FR1). The requirements may be applicable to NR FR1-FR1 intra-frequency PCell handover and NR FR1-FR1 intra-frequency PSCell change when the target PSCell is configured with a 12PRB SSB bandwidth.

[0073] In some embodiments, when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less comprising no more than twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time1884.R76WO1 AG9579-PCT(i.e., for transmitting the PRACH to add or change to the target PSCell) may be greater than when the SSBs of the PSCell are within a 10 MHz bandwidth comprising 20 PRBs with the subcarrier spacing of 15 kHz in FR1. In these embodiments, more time may be allowed when the PSCell is transmitted within a narrower bandwidth.

[0074] In some embodiments, when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less comprising up to twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time (i.e., for transmitting the PRACH to add or change to the target PSCell) may be greater than when the SSBs of the PSCell are within a 10 MHz bandwidth comprising 20 PRBs with the subcarrier spacing of 15 kHz in FR1. In these embodiments, more time may be allowed when the PSCell is transmitted within a narrower bandwidth.

[0075] In some embodiments, when the UE is in a radio-resource control (RRC) connected state with a primary cell (PCell) (Cell 1), the PCell being a first serving cell, the UE may be configured to add a primary secondary cell (PSCell) (Cell 2) as a second serving cell for NR dual connectivity (NR DC) operation with the first serving cell, the PCell and the PSCell being on different radio channels. In these embodiments, the UE may be configured to transmit a measurement report within a predetermined period of time (e.g., 680 ms) after a deactivation of the PSCell. These embodiments may relate to measurement reporting of a deactivated PSCell in NR-DC operation.

[0076] In some embodiments, within the predetermined time period after deactivation of the PSCell, the UE may be configured to detect primary synchronization signals (PSS) and secondary synchronization signals (SSS) of the deactivated PSCell, detect a synchronization signal block (SSB) index of the deactivated PSCell, perform measurements on the deactivated PSCell, generate the measurement report that includes the measurements, and transmit the measurement report.

[0077] In some embodiments, synchronization signal blocks (SSBs) of the target PSCell are transmitted within a 3 MHz bandwidth or less comprising no more than twelve physical resource blocks (12 PRBs) with a subcarrier1884.R76WO1 AG9579-PCTspacing of 15 kHz in frequency range 1 (FR1). In these embodiments, the predetermined time period after deactivation of the PSCell may be 680 milliseconds (ms).

[0078] In some embodiments, the UE may be configured to detect the PSS and the SSS of the deactivated PSCell within 200 ms after deactivation of the PSCell, detect the SSB index of the deactivated PSCell within 280 ms after detection of the PSS and the SSS, and perform the measurements on the deactivated PSCell within 200 ms after detection of the SSB index. In some embodiments, to add the PSCell as the second serving cell for NR-DC operation, UE may be configured to transmit a PRACH on the PSCell.

[0079] In some embodiments, in a testing scenario, the UE may be in the RRC connected state with the source PCell provided by a system simulator, the PSCell may be provided by the system simulator, and SSBs of the PSCell are transmitted by the system simulator within the 3 MHz bandwidth comprising the 12 PRBs with the subcarrier spacing of 15 kHz in FR1.

[0080] In some embodiments, when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less comprising no more than twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the predetermined period of time (i.e., for transmitting the measurement report) may be greater than when the SSBs of the PSCell are within a 10 MHz bandwidth comprising 20 PRBs with a subcarrier spacing of 15 kHz in FR1. In these embodiments, more time may be allowed when the PSCell is transmitted within a narrower bandwidth.

[0081] Some embodiments are directed to a computer-readable storage medium that stores instructions for execution by processing circuitry of a system simulator for verifying NR-DC (FR1-FR1) handover delay and for verifying PSCell addition or change delay during the handover for a user equipment (UE). In these embodiments, the instructions may configure the processing circuitry to cause the system simulator to generate signalling to simulate a source primary cell (PCell) (Celli) for establishment of a radio-resource control (RRC) connected state with the UE. In these embodiments, the instructions may also configure the processing circuitry to cause the system simulator to transmit an1884.R76WO1 AG9579-PCTRRC handover command forNR-DC FR1-FR1 intra-frequency PCell handover and NR-DC FR1-FR1 intra-frequency PSCell addition or change at handover.

[0082] In these embodiments, the instructions may also configure the processing circuitry to cause the system simulator to generate signalling to simulate a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after transmission of the RRC handover command. In these embodiments, the instructions may also configure the processing circuitry to cause the system simulator to receive a first PRACH handover to the target PCell within a first predetermined time period after transmission of the RRC handover command. In these embodiments, the instructions may also configure the processing circuitry to cause the system simulator to receive a second PRACH to add or change to the target PSCell within a second predetermined time period after transmission of the RRC handover command. In these embodiments when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less comprising up to twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time (i.e., for transmitting the PRACH to add or change to the target PSCell) may be greater than when the SSBs of the PSCell are within a 10 MHz bandwidth comprising 20 PRBs with the subcarrier spacing of 15 kHz in FR1.

[0083] FIG. 2 illustrates a testing scenario, in accordance with some embodiments. As shown in FIG. 2, a device under test (DUT) 202 may be tested by a system simulator 204. In some embodiments, the DUT 202 may be a UE, and the system simulator may simulate a gNB of a 5G NR network. In these embodiments, when the UE is in a radio-resource control (RRC) connected state 206 with a source primary cell (PCell) (Celli), the system simulator may be configured to transmit an RRC handover command 208. The DUT 202 may detect a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after receipt of the RRC handover command. Signals representing the source PCell, the target PCell and the target PSCell may be generated by the system simulator 204.

[0084] In response to the RRC handover command 208, the DUT 202 may transmit a first physical random access channel (PRACH) 210 for handover1884.R76WO1 AG9579-PCTto the target PCell within a first predetermined time period after receipt of the RRC handover command. The DUT 202 may also transmit a second PRACH 212 to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover command.

[0085] These embodiments may verify the handover delay requirements in NR-DC (FR1-FR1) and PSCell addition / change delay requirements during handover with PSCell from NR-DC (FR1-FR1) to NR-DC (FR1-FR1).

[0086] In some of these embodiments, the synchronization signal blocks (SSBs) of the target PSCell may be transmitted within a 3 MHz bandwidth or less comprising twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in FR1.

[0087] FIG. 3 illustrates a functional block diagram of a wireless communication device, in accordance with some embodiments. Wireless communication device 300 may be suitable for use as a UE or gNB configured for operation in a 5GNR or 6G network. Some embodiments are directed to an apparatus of a UE or gNB comprising processing circuitry and memory configured for operation in a 5GNR or 6G network. The wireless communication device 300 may include communications circuitry 302 and a transceiver 310 for transmitting and receiving signals to and from other communication devices using one or more antennas 301. The communications circuitry 302 may include circuitry that can operate the physical layer (PHY) communications and / or medium access control (MAC) communications for controlling access to the wireless medium, and / or any other communications layers for transmitting and receiving signals. The wireless communication device 300 may also include processing circuitry 306 and memory 308 arranged to perform the operations described herein. In some embodiments, the communications circuitry 302 and the processing circuitry 306 may be configured to perform operations detailed in the above figures, diagrams, and flows.

[0088] In accordance with some embodiments, the communications circuitry 302 may be arranged to contend for a wireless medium and configure frames or packets for communicating over the wireless medium. The communications circuitry 302 may be arranged to transmit and receive signals.1884.R76WO1 AG9579-PCTThe communications circuitry 302 may also include circuitry for modulation / demodulation, upconversion / downconversion, filtering, amplification, etc. In some embodiments, the processing circuitry 306 of the wireless communication device 300 may include one or more processors. In other embodiments, two or more antennas 301 may be coupled to the communications circuitry 302 arranged for sending and receiving signals. The memory 308 may store information for configuring the processing circuitry 306 to perform operations for configuring and transmitting message frames and performing the various operations described herein. The memory 308 may include any type of memory, including non-transitory memory, for storing information in a form readable by a machine (e.g., a computer). For example, the memory 308 may include a computer-readable storage device, read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices and other storage devices and media.

[0089] In some embodiments, the wireless communication device 300 may be part of a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), a wearable computer device, or another device that may receive and / or transmit information wirelessly.

[0090] In some embodiments, the wireless communication device 300 may include one or more antennas 301. The antennas 301 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmission of RF signals. In some embodiments, instead of two or more antennas, a single antenna with multiple apertures may be used. In these embodiments, each aperture may be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, the antennas may be effectively separated for spatial diversity and1884.R76WO1 AG9579-PCTthe different channel characteristics that may result between each of the antennas and the antennas of a transmitting device.

[0091] In some embodiments, the wireless communication device 300 may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen.

[0092] Although the wireless communication device 300 is illustrated as having several separate functional elements, two or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and / or other hardware elements. For example, some elements may include one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radiofrequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements of the wireless communication device 300 may refer to one or more processes operating on one or more processing elements.

[0093] Although the mobile device is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and / or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements.

[0094] Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read1884.R76WO1 AG9579-PCTand executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include readonly memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

[0095] FIG. 4 illustrates procedure 400 for verifying performance of a User Equipment (UE) for adding or changing a target PSCell after receipt of an RRC handover command, in accordance with some embodiments.

[0096] In operation 402, the UE is in a RRC connected state with a source PCell. In operation 404, the UE receives an RRC handover command. The RRC handover command may be for NR-DC FR1-FR1 intra-frequency PCell handover and NR-DC FR1-FR1 intra-frequency PSCell addition or change at handover.

[0097] In operation 406, the UE detects a target PCell and a target PSCell after receipt of the RRC handover command. In response to the RRC handover command, in operation 408, the UE transmits a first PRACH for handover to the target PCell within a first predetermined time period after receipt of the RRC handover command. In response to the RRC handover command, in operation 410, the UE transmits a second PRACH to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover command.

[0098] In these embodiments, the synchronization signal blocks (SSBs) of the target PSCell may be transmitted within a 3 MHz bandwidth or less comprising twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in FR1.

[0099] Test method for handover with PSCell

[0100] Test Purpose

[0101] The purpose of this test is to verify the handover delay requirements and PSCell change delay requirements in HO with PSCell from1884.R76WO1 AG9579-PCTNR-DC (FR1-FR1) to NR-DC (FR1-FR1). The requirements are applicable to NR FR1-FR1 intra-frequency PCell handover and NR FR1-FR1 intra-frequency PSCell change. The requirements are applicable when the target PSCell is configured with 12PRB SSB bandwidth.

[0102] Test parameters

[0103] The supported test configurations are given in table 1. The test scenario comprises 3 NR cells, source PCell(Cell 1), target PCell(Cell 2), target PSCell(Cell 3).

[0104] Cell 1 and Cell 2 are on radio channel 1. Cell 3 is on radio channel 2. Test parameters are given in Tables 2, 3, 4 and 5 below. Note that for Cell 3 the SSB configuration refers to SSB pattern 13 in FR1: SSB allocation for SSB SCS=15kHz in 3 MHz. In the test, the SSB is configured with 12PRB bandwidth.

[0105] The test consists of two successive time periods, with time durations of T1 and T2 respectively. At the start of Tl, the UE shall be connected to Cell 1 on radio channel 1. UE is not aware of Cell 2 and Cell 3. Starting T2, Cell 2 and Cell 3 becomes detectable to the UE, and the UE receives a RRC handover command from the network. The start of T2 is the instant when the last TTI containing the RRC message implying handover is sent to the UE.

[0106] The UE is required to successfully handover from Cell 1 to Cell 2 and at the same time in time period T2 add Cell 3 as PSCell attached to Cell 2. This test case verifies the delay starting from the start of T2 to time points where the UE finishes handover to Cell 2 and where the UE finishes addition of Cell 3. Test cases delay requirements are specified.Table 1: Supported test configurations for HO with PSCell with 12PRB SSB bandwidthConfig Description1 Source PCell: FR1 NR 15 kHz SSB SCS, 10 MHz bandwidth, FDD duplex modeTarget PCell: FR1 NR 15 kHz SSB SCS, 10 MHz bandwidth, FDD duplex mode Target PSCell: FR1 NR 15 kHz SSB SCS, 3 MHz bandwidth, FDD duplexmodeTable 2: General test parameters for Intra-frequency handover Parameter Unit Value Comment Initial Active cell Cell 1conditionsNeighboring cell Cell 21884.R76WO1 AG9579-PCTFinal Active cell Cell 2conditionAccess Barring Information - Not Sent No additional delays in random access procedure. T1 s 2T2 s <5Table 3: Cell specific test parameters for Intra-frequency handover Parameter Unit Cell 1 Cell 2 T1 T2NR RF Channel Number 1Duplex mode Config 1 FDDTDD Config 1 Not Applicable configurationBWchannel Config 1 MHz 10: NPRB.C=52BWP BW Config 1 MHz 10: NPRB.C=52TRS Config 1 TRS.1.1 FDD configurationDRX Cycle ms Not Applicable PDSCH Config 1 SR.1.1 FDD ReferencemeasurementchannelCORESET Config 1 CR.1.1 FDD ReferenceChannelOCNG Patterns OP.1SMTC Configuration SMTC.1SSB Config 1 SSB.1 FR1 ConfigurationPDSCH / PDCC Config 1 kHz 15 kHzH subcarrierspacingPUCCH / PUSC Config 1 kHz 15 kHzH subcarrierspacingPRACH configuration FR1 PRACH configuration 1 BWP Initial DL BWP DLBWP.0.1Dedicated DL BWP DLBWP.1.1 Initial UL BWP ULBWP.0.1 Dedicated UL BWP ULBWP.1.1 EPRE ratio of PSS to SSS dB 0EPRE ratio of PBCH DMRS to SSSEPRE ratio of PBCH to PBCHDMRS EPRE ratio of PDCCH DMRS toSSS EPRE ratio of PDCCH to PDCCHDMRS EPRE ratio of PDSCH DMRS toSSS EPRE ratio of PDSCH to PDSCHDMRS EPRE ratio of OCNG DMRS toSSS(Note 1)EPRE ratio of OCNG to OCNGDMRS (Note 1)M Note2 dBm / 15kHz -981884.R76WO1 AG9579-PCTParameter Unit Cell 1 Cell 2 T1 T2 T1 T 2 Note2 Config 1 dBm / SCS -98Es / IotdB 8 8 -Infinity 12 / dB 8 8 -Infinity 12 SSB_RP Config 1 dBm / SCS -90 -90 - InfinityIgNoteS Config 1 dBm / -61.41 -61.41 - Infinity 9.36 MHz 57 7 8Propagation condition - AWGN AWGN NOTE 1 : OCNG shall be used such that both cells are fully allocated and a constant total transmitted power spectral density is achieved for all OFDM symbols.NOTE 2: Interference from other cells and noise sources not specified in the test is assumed to be constant over subcarriers and time and shall be modelled as AWGN of appropriate power for Nocto be fulfilled.NOTE 3: Io levels have been derived from other parameters for information purposes. They arenot settable parameters themselves.Table 4: General test parameters Intra-frequency FR1-FR1 PSCell changeParameter Unit Value Comment Initial Active cell Cell 2conditionsNeighboring cell Cell 4Final Active cell Cell 4conditionAccess Barring Information - Not Sent No additional delays in random access procedure.T1 s 5T2 s <55 Table 5: Cell specific test parameters for Cell 3Parameter Unit Cell 3T1 | T2 NR RF Channel Number 2Duplex mode Config 1 FDDTDD Config 1 Not Applicable configurationBWchannel Config 1 MHz 3: NPRB.C = 15BWP BW Config 1 MHz 3: NPRB.C = 15TRS Config 1 TRS.1.1 FDD configurationDRX Cycle ms Not ApplicablePDSCH Config 1 SR.1.2 FDD ReferencemeasurementchannelCORESET Config 1 CR.1.2 FDDReference1884.R76WO1 AG9579-PCTParameter Unit Cell 3T1 T2 ChannelOCNG Patterns OP.1SMTC Configuration SMTC.1SSB Config 1 SSB.13 FR1 ConfigurationPDSCH / PDCC Config 1 kHz 15 kHzH subcarrierspacingPUCCH / PUSC Config 1 kHz 15 kHzH subcarrierspacingPRACH configuration FR1 PRACH configuration 1BWP Initial DL BWP DLBWP.0.1Dedicated DL BWP DLBWP.1.1 Initial UL BWP ULBWP.0.1 Dedicated UL BWP ULBWP.1.1 EPRE ratio of PSS to SSS dB 0EPRE ratio of PBCH DMRS to SSSEPRE ratio of PBCH to PBCH DMRSEPRE ratio of PDCCH DMRS to SSSEPRE ratio of PDCCH to PDCCHDMRS EPRE ratio of PDSCH DMRS to SSSEPRE ratio of PDSCH to PDSCHDMRS EPRE ratio of OCNG DMRS toSSS(Note 1)EPRE ratio of OCNG to OCNGDMRS (Note 1)jy Note2 dBm / 15kHz -98Note2 Config 1 dBm / SCS -98Es / IotdB -Infinity 12 / dB -Infinity 12 SSB_RP Config 1 dBm / SCS -Infinity -86 IgNoteS Config 1 dBm / -Infinity -85.7SCS MHzPropagation condition - AWGN AWGN NOTE 1 : OCNG shall be used such that both cells are fully allocated and a constant total transmitted power spectral density is achieved for all OFDM symbols.NOTE 2: Interference from other cells and noise sources not specified in the test is assumed to be constant over subcarriers and time and shall be modelled as AWGN of appropriate power for to be fulfilled.NOTE 3: Io levels have been derived from other parameters for information purposes. They are not settableparameters themselves.Handover to PCell delay requirementsIn this test, the UE shall start to transmit the PRACH to target PCell (Cell 2) less than

[0078] ms from the beginning of time period T2.5 The handover delay is defined asDHOwithPsceii pcdi = RRC procedure delay + Tinterrupt, whereTinterrupt Tsearch + T|u + T processing + TA + TmarginThe UE is required to follow the below parameters according to derivation from 0 the test setup specified:1884.R76WO1 AG9579-PCT- RRC procedure delay = 16 ms,Tsearch — 20 ms,- Tiu = 20 ms where PRACH association period should be configured as 1, Tprocessing ~ 20 ms,Tmargin ~ 2ms.That sums up to 78ms exactly.PSCell change addition delay requirementsThe UE shall transmit the PRACH to target PSCell (Cell 3) no later than

[0178] ms from the beginning of time period T2.PSCell change delay during handover is defined asDHOwithPSCell PSCell = TRRC delay + Tprocessing + Tsearch PCell + Tsearch PSCell + TA + Tpsceii DU + 2 ms.In this test the UE is required to follow the below parameters according to derivation from the test setup specified:TRRC_ delay—16ms,Tprocessing ~ 20 fTIS,Tsearch _PCell - 0,Tsearch_PSCell—60 HIS,- = 60 ms,- Tpsceii_Du = 1*10+10 = 20 ms where PRACH association period should be configured as 1.That sums up to 178ms exactly.

[0107] The test is considered successful only when both requirements are correctly verified, and the success rate during repeated tests shall be at least 90

[0108] Test method for deactivated PSCell measurements

[0109] Test Purpose

[0110] The purpose of this test is to verify that the UE makes correct reporting of deactivated PSCell measurement results when the PSCell is configured with 12 PRB SSB bandwidth. This test verifies the deactivated PSCell measurement period requirements.

[0111] Test Parameters

[0112] The supported test configurations are given in table 1. The test scenario comprises 2 NR cells - PCell (Cell 1) and target PSCell (Cell 2).

[0113] Cell 1 is on radio channel 1. Cell 2 is on radio channel 2. Test parameters are given in Tables 2 and 3 below. Note that for Cell 2 the SSB configuration refers to SSB pattern 13 in FR1: SSB allocation for SSB SCS=15kHz in 3 MHz. In the test, the SSB is configured with 12PRB bandwidth.1884.R76WO1 AG9579-PCT

[0114] The test consists of two successive time periods, with time duration of Tl, and T2 respectively. At the start of Tl, the UE is in connected mode to Cell 1. During time duration Tl, the UE is configured to add Cell 2 as PSCell so that Cell 1 and Cell 2 serve UE under NR-DC operation. Meanwhile the UE is configured to measure on both Cell 1 and Cell 2 serving carrier frequencies. The UE is configured to read the SSB index of the target deactivated PSCell.

[0115] At the end of Tl, the UE deactivates Cell 2. T2 starts exactly when the UE starts carrying out deactivated PSCell measurements on Cell 2. During T2, Cell 2 remains detectable to the UE. Measurement gap or DRX is not configured. The UE is required to make correct and timely reporting during T2. This test case verifies that the UE reporting is within the delay requirement and measurement accuracy is tested in other test cases.Table 1: Supported test configurationConfig Description1 NR 15 kHz SSB SCS, PCell with 10 MHz bandwidth and PSCell with 3 MHz bandwidth, both FDD duplex modeTable 2: General test parameters for deactivated PSCell measurements when PSCell is configured with 12 PRB SSB bandwidthParameter Unit Test Value Comment configurationNR RF Channel Config 1 1, 2 Two FR1 NR carrier Number frequencies arePCell Config 1 NR Cell 1 (PCell) NR Cell 1 is on NR RF channel number 1.Deactivated Config 1 NR Cell 2 NR Cell 2 is on NR RF PSCell channel number 2. measCyclePSCell ms Config 1 20 Same as SMTC and SSB periodicityGap Pattern Id Config 1 Not configuredMeasurement Config 1 Not configuredgap offsetSMTC-SSB Config 1 SSB.1 FR1 for As specified in clause parameters Cell 1 A.3.10.1SSB.13 FR1 forCell 2CP length Config 1 NormalTimeToTrigger s Config 1 0Filter coefficient Config 1 0 L3 filtering is not usedDRX Config 1 OFF DRX is not used1884.R76WO1 AG9579-PCTParameter Unit Test Value Comment configurationTime offset Config 1 3 ms Asynchronous cells. between cells The timing of Cell 2 is 3 ms later than the timing of Cell 1.T1 s Config 1 5T2 s Config 1 1Table 3: Cell specific test parameters for deactivated PSCell measurement with 12 PRB SSB bandwidth Parameter Unit Test Cell 1 Cell 2 configurationT1 | T2 T1 | T2 NR RF Channel Number Config 1 1 2 Duplex mode Config 1 FDDTDD configuration Config 1 Not Applicable BWchannel MHz Config 1 10: NPRB.C - 52 3: NPRB.C - 15 BWP BW MHz Config 1 10: NPRB.C=52 3: NPRB.C = 15 BWP Initial DL Config 1 DLBWP.0.1 DLBWP.0.1 configuration BWPInitial UL ULBWP.0.1 ULBWP.0.1 BWPDedicated DLBWP.1.1 DLBWP.1.1 DL BWPDedicated ULBWP.1.1 ULBWP.1.1 UL BWP TRS configuration Config 1 TRS.1.1 FDD NA OCNG Patterns defined in Config 1 OP.1 OP.1 A.3.2.1.1 (OP.1)PDSCH Reference Config 1 SR.1.1 FDD SR.1.2FDD measurement channelRMSI CORESET Config 1 CR.1.1 FDD CR.1.2 FDD Reference ChannelDedicated CORESET Config 1 CCR1.6 FDD Reference Channel CCR.1.1 FDDSSB parameters Config 1 SSB.1 FR1 SSB.13 FR1 SMTC configuration Config 1 SMTC.2 SMTC.1 defined in A.3.11PDSCH / PDCCH kHz Config 1 15 subcarrier spacingEPRE ratio of PSS to SSS Config 1 0 0 EPRE ratio of PBCHDMRS to SSSEPRE ratio of PBCH toPBCH DMRS EPRE ratio of PDCCHDMRS to SSSEPRE ratio of PDCCH toPDCCH DMRS EPRE ratio of PDSCHDMRS to SSSEPRE ratio of PDSCH toPDSCH EPRE ratio of OCNGDMRS to SSS(Note 1)EPRE ratio of OCNG toOCNG DMRS (Note 1)1884.R76WO1 AG9579-PCTParameter Unit Test Cell 1 Cell 2configurationT1 | T2 T1 | T2 dBm / 15 -98 -98 kHzdBm / SCS Config 1 -98 -98 SS-RSRPNote 3dBm / SCS Config 1 -94 -91 E. / h, dB Config 1 4 7 EJNOCdB Config 1 4 7dBm / SCS Config 1 -92.6 -90.2 MHzPropagation Condition Config 1 AWGN AWGN NOTE 1 : OCNG shall be used such that both cells are fully allocated and a constant total transmitted power spectral density is achieved for all OFDM symbols. NOTE 2: Interference from other cells and noise sources not specified in the test is assumed to be constant over subcarriers and time and shall be modelled as AWGN of appropriate power for Nxto be fulfilled.NOTE 3: SS-RSRP and Io levels have been derived from other parameters for information purposes. They are not settable parameters themselves.NOTE 4: SS-RSRP minimum requirements are specified assuming independentinterference and noise at each receiver antenna port.

[0116] The UE shall send one measurement report for the deactivated PSCell, with a measurement reporting delay less than 680 ms from the beginning of time period T2. The UE is required to successfully detect PSS / SSS for Cell 2 withinCeil(5 x Kp) x measCyclePSCell x CSSFintra;The UE is required to successfully read the SSB index for Cell 2 within Ceil(7 x Kp) x measCyclePSCell x CSSFintra;The UE is required to successfully measure on Cell 2 withinCeil(5 x Kp) x measCyclePSCell x CSSFintra;WheremeasCyclePSCell = 20 ms,- Kp= 1,2.

[0117] This sums up as 680 ms in total, consisting of 200 ms of PSS / SSS detection, 280 ms of SSB index detection and 200 ms of measurement time. The rate of correct events observed during repeated tests shall be at least 90%.

[0118] The Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The1884.R76WO1 AG9579-PCTfollowing claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Claims

1884.R76WO1 AG9579-PCTCLAIMSWhat is claimed is:

1. A User Equipment (UE) configured for operation in a fifth-generation new radio (5GNR) network, the UE comprising: processing circuitry; and memory,wherein when the UE is in a radio-resource control (RRC) connected state with a source primary cell (PCell) (Celli), the processing circuitry is configured to:receive an RRC handover command;detect a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after receipt of the RRC handover command; andin response to the RRC handover command:transmit a first physical random-access channel (PRACH) for handover to the target PCell within a first predetermined time period after receipt of the RRC handover command; andtransmit a second PRACH to add or change to the target PSCell within a second predetermined time period after receipt of the RRC handover command.

2. The UE of claim 1, wherein the RRC handover command is for NR Dual Connectivity (NR-DC) Frequency Range 1 (FR1) to FR1 (NR-DC FR1-FR1) intra-frequency PCell handover and indicates NR-DC FR1-FR1 intrafrequency PSCell addition or change at handover.

3. The UE of claim 2, wherein synchronization signal blocks (SSBs) of the target PSCell are transmitted within a 3 MHz bandwidth or less comprising twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in FR1.

4. The UE of claim 3, wherein, SSBs of the source PCell and SSBs of the target PCell are transmitted within a 10 MHz bandwidth with a subcarrier spacing of 15 kHz in FR1.1884.R76WO1 AG9579-PCT5. The UE of claim 4, wherein the first predetermined time period is 78 milliseconds (ms) and the second predetermined time period is 178 ms.

6. The UE of claim 4, wherein the target PCell and the target PSCell become detectable by the UE after receipt of the RRC handover command.

7. The UE of claim 6, wherein in response to the RRC handover command, the processing circuitry is to configure the UE to:transmit the first PRACH handover to the target PCell within the first predetermined time period after a last transmission time interval (TTI) that contains the RRC handover command; andtransmit the second PRACH to add or change to the target PSCell within the second predetermined time period after the last TTI that contains the RRC handover command.

8. The UE of claim 7, wherein the last TTI comprises a last slot in which a physical downlink shared channel (PDSCH) carrying that RRC handover command is received by the UE, the RRC handover command comprising an RRC reconfiguration message.

9. The UE of claim 4 wherein the source PCell, the target PCell and the target PSCell are configured for frequency domain duplex (FDD) operation.

10. The UE of claim 4, wherein in a testing scenario, the UE is in the RRC connected state with the source PCell provided by a system simulator, the RRC handover command is received from the system simulator, and the target PCell and the target PSCell are provided by the system simulator, and the SSBs of the target PSCell are transmitted by the system simulator within the 3 MHz bandwidth comprising the 12 PRBs with the subcarrier spacing of 15 kHz in FR1.

11. The UE of claim 2, wherein when synchronization signal blocks (SSBs) of the target PSCell are within twelve physical resource blocks (121884.R76WO1 AG9579-PCTPRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time is greater than when the SSBs of the PSCell are within 20 PRBs with the subcarrier spacing of 15 kHz in FR1.

12. The UE of claim 2, wherein when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time is greater than when the SSBs of the PSCell are within a 10 MHz bandwidth with the subcarrier spacing of 15 kHz in FR1.

13. A User Equipment (UE) configured for operation in a fifth-generation new radio (5GNR) network, the UE comprising: processing circuitry; and memory,wherein, when the UE is in a radio-resource control (RRC) connected state with a primary cell (PCell) (Cell 1), the PCell being a first serving cell, the processing circuitry is configured to:add a primary secondary cell (PSCell) (Cell 2) as a second serving cell for NR dual connectivity (NR DC) operation, the PCell and the PSCell being on different radio channels;cause the UE to transmit a measurement report within a predetermined period of time after a deactivation of the PSCell.

14. The UE of claim 13, wherein within the predetermined time period after deactivation of the PSCell, the processing circuitry is to configure the UE to:detect primary synchronization signals (PSS) and secondary synchronization signals (SSS) of the deactivated PSCell;detect a synchronization signal block (SSB) index of the deactivated PSCell;perform measurements on the deactivated PSCell;generate the measurement report that includes the measurements; and transmit the measurement report.1884.R76WO1 AG9579-PCT15. The UE of claim 14, wherein synchronization signal blocks (SSBs) of the PSCell are transmitted within a 3 MHz bandwidth comprising twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), andwherein the predetermined time period is 680 milliseconds (ms).

16. The UE of claim 15, wherein the processing circuitry to configure the UE to:detect the PSS and the SSS of the deactivated PSCell within 200 ms after deactivation of the PSCell;detect the SSB index of the deactivated PSCell within 280 ms after detection of the PSS and the SSS; andperform the measurements on the deactivated PSCell within 200 ms after detection of the SSB index.

17. The UE of claim 16, wherein to add the PSCell as the second serving cell for NR-DC operation, the processing circuitry configures the UE to transmit a PRACH on the PSCell, andwherein in a testing scenario, the UE is in the RRC connected state with the PCell provided by a system simulator, the PSCell is provided by the system simulator, and SSBs of the PSCell are transmitted by the system simulator within the 3 MHz bandwidth comprising the 12 PRBs with the subcarrier spacing of 15 kHz in FR1.

18. The UE of claim 12 wherein when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth comprising twelve physical resource blocks (12 PRBs) with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the predetermined period of time is greater than when the SSBs of the PSCell are within a 10 MHz bandwidth with a subcarrier spacing of 15 kHz in FR1.

19. A computer-readable storage medium that stores instructions for execution by processing circuitry of a system simulator for verifying NR-DC1884.R76WO1 AG9579-PCT(FR1-FR1) handover delay and for verifying PSCell addition or change delay during the handover for a user equipment (UE),wherein the instructions configure the processing circuitry to cause the system simulator to:generate signalling to simulate a source primary cell (PCell) (Celli) for establishment of a radio-resource control (RRC) connected state with the UE; transmit an RRC handover command forNR-DC FR1-FR1 intrafrequency PCell handover and NR-DC FR1-FR1 intra-frequency PSCell addition or change at handover;generate signalling to simulate a target PCell (Cell 2) and a target primary secondary cell (PSCell) (Cell 3) after transmission of the RRC handover command;receive a first PRACH handover to the target PCell within a first predetermined time period after transmission of the RRC handover command; andreceive a second PRACH to add or change to the target PSCell within a second predetermined time period after transmission of the RRC handover command.

20. The computer-readable storage medium of claim 19, wherein when synchronization signal blocks (SSBs) of the target PSCell are within a 3 MHz bandwidth or less with a subcarrier spacing of 15 kHz in frequency range 1 (FR1), the second predetermined period of time is greater than when the SSBs of the PSCell are within a 10 MHz bandwidth with the subcarrier spacing of 15 kHz in FR1.

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