Data reception on source cell during handover procedure

Abstract

Systems, methods, apparatuses, and computer program products are provided for reducing handover interrupt duration through data reception on a source cell during a handover procedure. For example, a method may include receiving, at a user equipment, a gap allocation configuration from a network. The method may also include preparing for handover to the target cell during the gap according to the gap allocation.

Description

Technical Field

[0001] Some example embodiments may generally relate to communications including mobile or wireless telecommunications systems, such as Long Term Evolution (LTE) or fifth generation (5G) radio access technology or new radio (NR) access technology, or other communications systems including subsequent generations of the same or similar standards. For example, certain example embodiments may generally relate to reducing the duration of a handover interruption by data reception on a source cell during a handover procedure. Background Art

[0002] Examples of mobile or wireless telecommunication systems may include Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE), Evolved UTRAN (E-UTRAN), Advanced LTE (LTE-A), MulteFire, LTE-A Pro, and / or fifth generation (5G) radio access technology or new radio (NR) access technology. 5G wireless systems refer to the next generation (NG) of radio systems and network architectures. 5G systems are mostly built on 5G New Radio (NR), but 5G (or NG) networks can also be built on E-UTRA radio. Starting with Release 18 (Rel-18), 5G is referred to as 5G Advanced. It is estimated that NR provides a bit rate of about 10-20Gbit / s or higher, and can support at least service categories such as enhanced mobile broadband (eMBB) and ultra-reliable low latency communication (URLLC) and massive machine type communication (mMTC). NR is expected to deliver extreme broadband and ultra-robust, low latency connections and large-scale networking to support the Internet of Things (IoT). As IoT and machine-to-machine (M2M) communications become more widespread, the demand for networks that meet the needs of lower power, low data rates and long battery life will continue to grow. The next generation radio access network (NG-RAN) represents a RAN for 5G that can provide both NR and LTE (and advanced LTE) radio access. Note that in 5G, a node that can provide radio access functions to user equipment (i.e., similar to a Node B, NB in ​​UTRAN or an evolved NB, eNB in ​​LTE) can be named a next generation NB (gNB) when built on an NR radio, and can be named a next generation eNB (NG-e NB) when built on an E-UTRA radio. 6G is currently under development and may replace 5G and 5G Advanced. Summary of the invention

[0003] Embodiments may relate to a terminal device. The terminal device may include at least one processor and at least one memory storing instructions. The instructions, when executed by the at least one processor, may cause the terminal device to at least perform the following operations: receiving a gap allocation configuration from a network. The instructions, when executed by the at least one processor, may also cause the terminal device to at least perform preparation for a handover to a target cell during a gap according to the gap allocation.

[0004] Embodiments may be directed to an apparatus. The apparatus may include at least one processor and at least a memory storing instructions. The instructions, when executed by the at least one processor, may cause the apparatus to at least perform determining that a user equipment will undergo a handover to a target cell. The instructions, when executed by the at least one processor, may also cause the apparatus to at least perform obtaining a gap allocation to be configured to the user equipment based on the determination. The instructions, when executed by the at least one processor, may also cause the apparatus to at least perform configuring the gap allocation to the user equipment.

[0005] Embodiments may be directed to a method. The method may include receiving a gap allocation configuration at a terminal device from a network. The method may also include preparing, by the terminal device, for a handover to a target cell during the gap according to the gap allocation.

[0006] Embodiments may be directed to a method. The method may include determining at an access network element that a user equipment will undergo a handover to a target cell. The method may also include obtaining, by the access network element, a gap allocation to be configured to the user equipment based on the determination. The method may also include configuring, by the access network element, the gap allocation to the user equipment.

[0007] Embodiments may relate to a terminal device. The terminal device may include means for receiving a gap allocation configuration from a network. The terminal device may also include means for preparing for a handover to a target cell during the gap according to the gap allocation.

[0008] Embodiments may be directed to an apparatus. The apparatus may include means for determining that a user equipment will undergo a handover to a target cell. The apparatus may also include means for obtaining a gap allocation to be configured to the user equipment based on the determination. The apparatus may also include means for configuring the gap allocation to the user equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] For a proper understanding of the example embodiments, reference should be made to the accompanying drawings, in which:

[0010] Figure 1 shows an estimate of the handover interruption duration for various types of handovers;

[0011] Figure 2 shows a signaling flow diagram for configuring a dynamic gap for a user equipment according to certain embodiments;

[0012] Figure 3 A signaling flow diagram illustrating various aspects of certain embodiments is shown;

[0013] Figure 4 Methods according to certain embodiments are shown;

[0014] Figure 5 Another method according to some embodiments is shown; and

[0015] Figure 6 An example block diagram of a system according to an embodiment is shown. DETAILED DESCRIPTION

[0016] It will be readily appreciated that the components of certain example embodiments as generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for providing a reduction in handover interruption duration by data reception on a source cell during a handover process is not intended to limit the scope of certain embodiments, but is representative of selected example embodiments.

[0017] The features, structures, or characteristics of the example embodiments described throughout this specification may be combined in any suitable manner in one or more example embodiments. For example, the use of the phrases "certain embodiments," "some embodiments," or other similar language throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment. Thus, the appearance of the phrases "certain embodiments," "in some embodiments," "in other embodiments," or other similar language throughout this specification does not necessarily all refer to the same set of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more example embodiments.

[0018] As used herein, “at least one of: ” and “at least one of ” and similar expressions, where a list of two or more elements is combined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0019] Certain embodiments may have various aspects and features. These aspects and features may be applied alone or in any desired combination with each other. Other features, processes, and elements may also be applied in combination with some or all of the aspects and features disclosed herein.

[0020] In addition, if desired, the different functions or processes discussed below can be performed in different orders and / or performed simultaneously with each other. In addition, if desired, one or more of the described functions or processes can be optional or can be combined. Therefore, the following description should be considered as an explanation of the principles and teachings of some example embodiments, rather than a limitation thereof.

[0021] Handover (HO) may occur many times in a wireless communication system, especially when a user equipment (UE) moves or radio conditions change in an area. HO may cause various problems, including disruption of the user plane (UP). Certain embodiments may relate to reducing user plane disruption during HO, which may result in other benefits, such as power savings and signaling reduction that may otherwise be required in the event of a user plane disruption during handover.

[0022] Figure 1 Estimation of the handover interruption duration for various types of handovers is shown. In the baseline handover, at 71ms, the estimated interruption duration is the longest in the example. In this case, the interruption duration may include the interruption from the handover command being received until the UE is fully connected to the new cell using the random access channel (RACH) procedure. In the layer 1 (L1) and layer 2 (L1 / L2) mobility central unit (CU), the interruption duration can be reduced by performing partial preparations before the actual handover. For example, handover preparations can be started using multiple candidates, and a handover to one of the candidate target cells can be triggered based on L1 / L2 measurements by sending a lower layer message. In this case, when the UE is triggered to perform the handover, the UE may have time to decode the RRC message and may not need additional time for such an activity. The same applies to conditional handover (CHO).

[0023] L1 / L2 mobility can improve the interruption duration, but when random access needs to be performed relative to the target cell, the interruption duration may still be significant. In some embodiments, the method can reduce the interruption. Although certain embodiments are described from the perspective of L1 / L2 switching, certain embodiments can be applied to any type of switching.

[0024] Also like Figure 1 As shown, a make-before-break (MBB) process may result in a 24ms outage. In this case, the main component contributing to the outage duration may be the RACH process. Certain embodiments may supplement MBB to reduce outages during the RACH process.

[0025] In some embodiments, the network can configure the UE with dynamic scheduling gaps as auxiliary information based on the network estimate of the next scheduling period. The UE can then use the gap auxiliary information to synchronize to the target cell, search for the RACH opportunity of the target cell, or even perform a RACH process. Once the UE has completed these processes, the UE can indicate to the source node that the source cell can initiate a handover and that the user plane process can be stopped. In this way, by avoiding performing the above functions at the time of handover, the UE can receive and send uninterrupted data on the source side until the last moment before the UE moves to the new cell. Specifically, synchronization with the target cell and searching for the RACH opportunity of the target cell can be completed before the user plane interruption occurs.

[0026] Certain embodiments may have various aspects. For example, a source radio access network (RAN) node, which may be referred to as a base station, may determine that a UE must undergo a handover to a target cell. The source RAN node may obtain a gap allocation or suggestion from the source RAN's own medium access control (MAC) probabilistic scheduler (MAC-PS), and optionally obtain a contention-free random access (CFRA) preamble allocation associated with a RACH-free HO from the target RAN.

[0027] In the case of a disaggregated Next Generation (NG) RAN (NG-RAN) node, the Central Unit (CU) Control Plane (CU-CP) may obtain scheduling gaps from a source Distributed Unit (DU), where the MAC-PS resides in the F1:UE Context Establishment or Modification process, and the CFRA preamble comes from the target DU.

[0028] In the case of a centralized NG-RAN node, the gNB may obtain the scheduling gap from the peer gNB in ​​the Handover Request Acknowledgement over the Xn interface. In this discussion, obtaining the scheduling gap may refer to obtaining information about when the scheduling gap will or should occur.

[0029] The source NG-RAN node may configure an UL gap allocation or suggestion to the UE using an RRCReconfiguration message. The message may also include timing advance information for the target cell. When the NG-RAN node indicates that the UE is about to undergo a handover, the UE may use the configured scheduling gap and the provided CFRA preamble to search for and send a preamble corresponding to the RACH opportunity of the target cell. In the case of lower layer mobility, the NG-RAN may indicate that the UE is about to undergo a handover using a DL MAC CE.

[0030] Once the UE acquires the timing advance information, the UE may start a validity timer for the timing advance. Parameters for the timer expiration may be configured by the network. If the UE performs access to the target cell while the timing advance is valid, the timer may be stopped. If the timer expires, the UE may indicate that the timer has expired or that the timing advance is no longer valid for the network and may reacquire the timing advance.

[0031] As another option, the network may monitor the validity of the timing advance and may instruct the UE to reacquire the timing advance from the target cell.

[0032] When the UE is prepared with multiple CFRA preambles for multiple target cells, the RAN node can use the scheduling gap to indicate which specific cell the UE should acquire timing advance from. In the case of lower layer mobility (LLM), the same MAC control element (CE) in the downlink (DL) can also be used to indicate a specific target, for example as an index, which is used to indicate when the UE should perform target synchronization.

[0033] The UE may indicate to the network that among multiple configured target cells, the UE may acquire a timing advance for a specific target cell. This selection by the UE may be related to the RACH timing configuration and UL gap configuration of the UE. In response to the indication from the UE, the network may reconfigure the UL gap for the UE.

[0034] Multiple target cells may align their RACH opportunities or preamble allocations for RACH-free timing advance acquisition procedures. This alignment may be achieved by dedicating RACH opportunities to timing advance acquisition for RACH-free (RACH less). A CFRA preamble allocated by one target cell may be indicated to other target cells. In the event that the CFRA preamble is not allocated to other UEs by other target cells, the same preamble may be allocated by other target cells to achieve synchronized CFRA preambles in the same RACH opportunity. Therefore, the same RACH preamble transmission may be used to acquire the TA of multiple target cells. In this case, a dedicated RACH preamble transmission for each target cell may not be required.

[0035] In advanced mobility mechanisms such as CHO and lower layer mobility, where multiple target cell configurations may be provided to the UE in advance, the gNB-DU may indicate to the UE the target cell ID to synchronize to using a DL MAC CE command. Synchronization may involve identifying the target cell, searching for RACH opportunities, performing RACH, etc.

[0036] Typically, in a gNB, there may be multiple UEs connected to the same cell, so one UE may not be scheduled continuously. For example, a voice UE may be scheduled at 20ms intervals, and basic non-guaranteed bit rate (GBR) data may be scheduled less frequently. From the UE's perspective, the relevant point is within the interruption duration between scheduling. If the handover can be prepared between scheduling occasions, the UE can essentially do a zero or almost zero interruption handover. If the UE does not know when the UE will be scheduled next, it may be challenging for the UE to plan ahead to prepare for the handover.

[0037] For a UE with a single data radio bearer (DRB) or a single service, the estimation of the scheduling gap can be done in a straightforward manner.

[0038] For a UE with multiple DRBs, the gNB may determine the scheduling gap based on the scheduling interval of the most frequently scheduled DRB. For example, if the UE has DRB A and DRB B with scheduling intervals of 10ms and 2ms respectively, the scheduling gap configured for the UE may be 2ms.

[0039] The gNB may classify UEs into different categories based on the scheduling gap of their DRBs. Each category may be given an index.

[0040] Furthermore, the scheduling gap may be configured to the UE during RRC reconfiguration (e.g., at DRB establishment, release, etc.). Any changes in the scheduling gap, e.g., due to DRB addition, release, or QoS parameter (such as QoS Flow Identifier (QFI)) changes, may be indicated to the UE using a DL MAC CE command.

[0041] The UE may also use a MAC CE command in the UL to indicate the completion of synchronization with the target cell.

[0042] In certain embodiments, the UE may be configured with a dynamic gap configuration via RRC. The dynamic gap configuration may include mapping options regarding gap lengths and optionally synchronization information regarding possible handover candidates. The mapping may map to aspects such as gap lengths, cell identifiers, etc. The gNB may configure the dynamic gap configuration for those UEs configured with, for example, L1 / L2 handover. When the gNB performs scheduling for the UE, the gNB may indicate after each data packet or scheduling interval when the next scheduling is scheduled to occur. This indication from the scheduler regarding the next scheduling may be a mapping to the dynamic gap options given for the UE with RRC.

[0043] The gNB may also use gNB internal algorithms to optimize the schedule when needed. The gNB may indicate the scheduling interval as well as the schedule to the UE in a MAC message. When the UE receives information about the next schedule, the UE may map the received information to a pre-configured RRC value. Another option is that the network may do the mapping and may indicate which pre-configured option to use. Either way, the UE may receive information about how much time the UE has. The UE may use this time to search for RACH parameters from neighboring cells. When the time is about to expire, the UE may return to the source cell, store the completed search results, and may continue to receive the next data and new gaps. The UE may continue this process until the UE has been able to find a strong neighbor of the cell and clarified the RACH timing or defined procedures. Once all defined procedures are clarified, the UE may leave the source cell at the right moment.

[0044] The network may estimate and define the length of the gap individually for each scheduling round or alternatively for longer periods. With certain embodiments, the handover interruption duration may even be optimized to zero in the best case, since the UE may know the moment when the UE may receive the last packet from the source cell, move to the new cell, and receive the next data packet.

[0045] Figure 2 FIG. 4 shows a signaling flow chart for configuring a dynamic gap for a user equipment according to some embodiments. Figure 2 As shown, at 1, the UE may be configured to perform measurements of neighbors. At 2, the UE may send (multiple) measurement results. At 3, the CU may configure L1 / L2 HO and may indicate to the DU that dynamic gaps are being used. Optionally, this may also include neighbor synchronization information to optimize (multiple) scheduling opportunities. At 4, there may be a UE context modification response from the DU to the CU.

[0046] At 5, the CU may configure the UE with an RRC reconfiguration and may include the use of dynamic gaps and information about neighbor cell synchronization of those neighbors known to the CU. The UE may use this information to optimize the neighbor search process. At 6, the UE may provide an RRC reconfiguration response.

[0047] At 7, the DU may schedule the UE and may indicate with an information element (IE) how much time the UE must search neighbor cells. At 8, the UE may synchronize to the neighbor cell(s) and / or search for RACH opportunities. At 9, the UE may return to the source cell to receive the next schedule and may again receive an indication of the length of the next gap before further scheduling. At 10, the UE may continue the search and synchronization process.

[0048] At 11, if the UE can find a neighbor with all the required parameters, it indicates this to the source cell. At 12, the UE can still optionally receive the last data schedule in the cell. Once the last data schedule in the cell is completed, the UE can move to a prepared new cell where the UE can receive the next data schedule. This synchronous movement can also allow keeping the UE scheduling interval almost the same and with as little as zero interruption duration.

[0049] Figure 3 A signaling flow diagram illustrating various aspects of certain embodiments is shown. Figure 3 As shown, at 1, during an Xn Setup Request, RAN nodes such as a source gNB and a target gNB may exchange RACH opportunities or RACH configurations assigned for the procedures of certain embodiments. In an Xn Setup Response, the source node may indicate to the UE the measurement gap configuration to be configured. The target node may use this information to schedule a random access response to the UE, if necessary.

[0050] At 2, the source gNB may receive a measurement report based on a previous measurement configuration provided to the UE. The measurement report may be a cell preparation event. Optionally, in the measurement report, the UE may indicate a timing advance acquisition request for the reported cell.

[0051] At 3, in response to the UE indicating the need to acquire timing advance, the network determines that the UE needs to be configured with measurement gaps to enable random access to the RACH opportunities of neighbor cells. Similarly, in an alternative option, the network may determine that cell 2 indicated by the measurement report may require acquisition of timing advance. This may result in the network determining to configure measurement gaps for the UE.

[0052] At 4, according to certain embodiments, the network may configure the UE with measurement gaps for the procedure. The measurement gaps may be indicated for obtaining timing advance. Optionally, the configuration may indicate to the UE that the timing advance is obtained from a specific cell.

[0053] At 5, 6, 7, 8 and 9, the UE may initiate random access to the target cell and interact with cell 2. If the UE uses a specific RACH opportunity or a specific preamble, which may be assigned process 1, then

[0054] The target node may determine to send a random access response to the UE using the gap allocated in process 1. Alternatively, the target node may determine to indicate the timing advance to the UE by the source gNB. Both the timing advance (TA) and the TA radio network temporary identifier (TA-RNTI) may be indicated to the UE to avoid erroneous timing advance indication.

[0055] At 10, the UE may start a validity timer for the TA. The validity timer may be configured to the UE with the timing advance information. Alternatively, the validity timer may be a fixed configuration, such as established by a standard or according to user equipment implementation.

[0056] At 11, in one case, the validity timer may expire and the UE may restart TA acquisition.

[0057] At 12 and 13, in another case, the network may determine that the TA is invalid and may instruct the UE to restart TA acquisition.

[0058] At 14, in one case, if the TA is valid, the UE may perform RACH-less HO.

[0059] Figure 4 Methods according to some embodiments are shown. Figure 4 The method can be executed by a user device, a terminal device, etc. Figure 4 As shown, at 410, the method may include receiving a gap allocation configuration from a network at a terminal device. The method may also include: at 420, preparing, by the terminal device, for a handover to a target cell during the gap according to the gap allocation. The gap allocation configuration may also include synchronization information about possible handover candidates. The preparation includes performing synchronization to the target cell before handover to the target cell.

[0060] Receiving the gap allocation at 410 may include receiving a timing advance configuration to obtain a timing advance for a target cell.

[0061] Figure 4 The method may further include, at 412, receiving, by the terminal device, a timing advance configuration from the target cell through the allocated gap.

[0062] The method may also include, at 414, upon receiving the timing advance, starting a validity timer associated with the timing advance at the terminal device.

[0063] The method may also include, at 416, indicating invalidation of the timing advance to the network upon expiration of the validity timer.

[0064] At 413, the method may include receiving, at the terminal device, from the network an identification of a target cell for which the timing advance acquisition or further timing advance acquisition is applicable. For example, further timing advance may be obtained after the initial timing advance is no longer valid. Thus, the terminal device may receive from the RAN node an indication of which particular cell the terminal device should use the scheduling gap to acquire the timing advance. In the case of LLM, this may also be received, for example, as an index using the same MAC CE in the DL that indicates when the terminal device should perform target synchronization.

[0065] Timing advance configuration may be provided to dedicated random access channel opportunities or preamble allocations to accommodate timing advance acquisition.

[0066] At 405, the method may include providing, by the terminal device, an identification of the target cell to the network. The gap allocation may be configured according to the target cell identified to the network. As described above, the gap allocation configuration may include mapping options regarding gap lengths.

[0067] The method may also include, after receiving the mapping options, receiving, at the terminal device, an indication of valid mapping options in the mapping options, at 418. Preparation for handover at 420 may be performed based on the indication of the valid mapping options.

[0068] Figure 5 Another method according to some embodiments is shown. Figure 5 The method can be performed by an access network element (such as gNB, etc.). Figure 5 The method can be executed alone or with Figure 4 The method combination is executed.

[0069] like Figure 5 As shown, a method may include: at 510, determining at an access network element that a user equipment will undergo a handover to a target cell.

[0070] The method may also include obtaining, by the access network element based on the determination, a gap allocation to be configured to the user equipment at 520. The obtaining may include obtaining the gap allocation from a source distributed unit or from a peer base station.

[0071] The method may also include: at 530, configuring the gap allocation to the user equipment by the access network element. Configuring the gap allocation to the user equipment may also include configuring the timing advance for the target cell to the user equipment. The method may also include: at 535, identifying the target cell for which the timing advance acquisition or another timing advance acquisition is applicable to the user equipment by the access network element. A dedicated random access channel opportunity or preamble allocation may be provided to accommodate the timing advance acquisition. Thus, the RAN node may indicate which specific cell the user equipment should acquire the timing advance from using the scheduling gap. In the case of LLM, this may also be indicated, for example, using the same MAC CE in the downlink as an index to indicate when the user equipment should perform target synchronization.

[0072] The method may further include: receiving, by the access network element, an indication of invalidity of the timing advance from the user equipment at 540. The method may further include: in response to the indication, instructing the user equipment to obtain additional timing advance from the target cell at 550.

[0073] At 505 , the method may include receiving, by an access network element, an identification of a target cell from a user equipment, wherein the gap allocation is configured according to the target cell identified by the user equipment.

[0074] Figure 6 An example of a system including an apparatus 10 according to an embodiment is shown. In an embodiment, the apparatus 10 may be a node, a host, or a server in a communication network, or serve such a network. For example, the apparatus 10 may be a network node, a satellite, a base station, a Node B, an evolved Node B (eNB), a 5GB node or access point, a next generation Node B (NG-NB or gNB), a TRP, a HAPS, an integrated access and backhaul (IAB) node, and / or a WLAN access point associated with a radio access network (such as an LTE network, 5G or NR). In some example embodiments, the apparatus 10 may be, for example, a gNB or other similar radio node.

[0075] It should be understood that in some example embodiments, the device 10 may include an edge cloud server as a distributed computing system, where the server and the radio node may be independent devices that communicate with each other via a radio path or via a wired connection, or they may be located in the same entity that communicates via a wired connection. For example, in certain example embodiments where the device 10 represents a gNB, it may be configured in a central unit (CU) and distributed unit (DU) architecture that divides the gNB functionality. In such an architecture, the CU may be a logical node that includes gNB functionality such as transfer of user data, mobility control, radio access network sharing, positioning and / or session management. The CU may control the operation of (multiple) DUs via a midhaul interface referred to as the F1 interface, and the (multiple) DUs may have one or more radio units (RUs) connected to the DU via a fronthaul interface. Depending on the functional splitting option, the DU may be a logical node that includes a subset of the gNB functionality. It should be noted that a person of ordinary skill in the art will understand that the device 10 may include Figure 6 Components or features not shown.

[0076] like Figure 6 As shown in the example of , the device 10 may include a processor 12 for processing information and executing instructions or operations. The processor 12 may be any type of general-purpose or special-purpose processor. In fact, as an example, the processor 12 may include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), a field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), and a processor based on a multi-core processor architecture or any other processing component. Although Figure 6 A single processor 12 is shown in FIG. 1 , but multiple processors may be utilized according to other embodiments. For example, it should be understood that in some embodiments, the apparatus 10 may include two or more processors that may form a multiprocessor system that may support multiprocessing (e.g., in which case the processor 12 may represent a multiprocessor). In some embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

[0077] Processor 12 may perform functions associated with the operation of device 10, which may include, for example, precoding of antenna gain / phase parameters, encoding and decoding of individual bits that form communication messages, formatting of information, and overall control of device 10, including processes related to reducing the duration of handover interruption by receiving data on the source cell during the handover process.

[0078] The device 10 may also include or be coupled to a memory 14 (internal or external), which may be coupled to the processor 12 for storing information and instructions that may be executed by the processor 12. The memory 14 may be one or more memories and of any type suitable for the local application environment, and may be implemented using any suitable volatile or non-volatile data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and / or removable memory. For example, the memory 14 may include any combination of random access memory (RAM), read-only memory (ROM), static storage devices such as magnetic disks or optical disks, hard disk drives (HDDs), or any other type of non-transitory machine or computer readable media or other suitable storage components. The instructions stored in the memory 14 may include program instructions or computer program code that, when executed by the processor 12, enables the device 10 to perform tasks as described herein. The term "non-transitory" as used herein may correspond to limitations on the medium itself (i.e., tangible, non-signal), rather than limitations on data storage persistence (e.g., RAM vs. ROM).

[0079] In an embodiment, the device 10 may also include or be coupled to a (internal or external) drive or port configured to accept and read an external computer-readable storage medium, such as an optical disk, a USB drive, a flash drive, or any other storage medium. For example, the external computer-readable storage medium may store a computer program or software for execution by the processor 12 and / or the device 10.

[0080] In some embodiments, the device 10 may also include or be coupled to one or more antennas 15 for sending signals and / or data to the device 10 and receiving signals and / or data from the device 10. The device 10 may also include or be coupled to a transceiver 18 configured to send and receive information. The transceiver 18 may include, for example, multiple radio interfaces that may be coupled to (multiple) antennas 15, or may include any other suitable transceiver components. The radio interface may correspond to a variety of radio access technologies, including one or more of Global System for Mobile Communications (GSM), Narrowband Internet of Things (NB-Io T), LTE, 5G, WLAN, Bluetooth (BT), Bluetooth Low Energy (BT-LE), Near Field Communication (NFC), Radio Frequency Identifier (RFID), Ultra Wideband (UWB), MulteFire, etc. The radio interface may include components such as filters, converters (e.g., digital-to-analog converters, etc.), mappers, Fast Fourier Transform (FFT) modules, etc., to generate symbols for transmission via one or more downlinks and receive symbols (e.g., via uplinks).

[0081] Thus, the transceiver 18 may be configured to modulate information onto a carrier waveform for transmission by the antenna(s) 15, and to demodulate information received via the antenna(s) 15 for further processing by other elements of the device 10. In other embodiments, the transceiver 18 may be capable of directly sending and receiving signals or data. Additionally or alternatively, in some embodiments, the device 10 may include input and / or output devices (I / O devices) or input / output components.

[0082] In an embodiment, memory 14 may store software modules that provide functionality when executed by processor 12. These modules may include, for example, an operating system that provides operating system functionality for device 10. Memory may also store one or more functional modules, such as applications or programs, to provide additional functionality to device 10. The components of device 10 may be implemented in hardware, or in any suitable combination of hardware and software.

[0083] According to some embodiments, the processor 12 and the memory 14 may be included in a processing circuit system / component or a control circuit system / component or may form a part of a processing circuit system / component or a control circuit system / component. In addition, in some embodiments, the transceiver 18 may be included in a transceiver circuit / device or may form a part of a transceiver circuit system / component.

[0084] As used herein, the term "circuitry" may refer to a hardware-only circuitry implementation (e.g., analog and / or digital circuitry), a combination of hardware circuitry and software, a combination of analog and / or digital hardware circuitry and software / firmware, any portion of hardware processor(s) and software (including digital signal processors) that work together to enable a device (e.g., device 10) to perform various functions, and / or hardware circuit(s) and / or processor(s), or portions thereof, that operate using software, but where the software may not be present when the software is not required for operation. As another example, as used herein, the term "circuitry" may also cover an implementation of a hardware-only circuit or processor (or multiple processors), or a portion of a hardware circuit or processor and its accompanying software and / or firmware. The term circuitry may also cover, for example, a baseband integrated circuit in a server, cellular network node or device, or other computing or network device.

[0085] As described above, in some embodiments, the device 10 may be a network element or a RAN node or may be part of a network element or a RAN node, such as a base station, an access point, a Node B, an eNB, a gNB, a TRP, a HAPS, an IAB node, a relay node, a WLAN access point, a satellite, etc. In an example embodiment, the device 10 may be a gNB or other radio node, or may be a CU and / or DU of a gNB. According to some embodiments, the device 10 may be controlled by the memory 14 and the processor 12 to perform functions associated with any of the embodiments described herein. For example, in some embodiments, the device 10 may be configured to perform one or more of the processes depicted in any of the flowcharts or signaling diagrams described herein, such as Figures 2 to 5 In some embodiments, as discussed herein, the apparatus 10 may be configured to perform processes related to providing handover interruption duration reduction, for example, by receiving data on a source cell during a handover process.

[0086] Figure 6 An example of an apparatus 20 according to an embodiment is also shown. In an embodiment, the apparatus 20 may be a node or element in a communication network or a node or element associated with such a network, such as a UE, a communication node, a mobile equipment (ME), a mobile station, a mobile device, a fixed device, an IoT device, or other device. As described herein, a UE may alternatively be referred to as, for example, a mobile station, a mobile device, a mobile unit, a mobile device, a user device, a subscriber station, a wireless terminal, a tablet, a smart phone, an IoT device, a sensor or a NB-IoT device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, a medical device and its application (e.g., remote surgery), an industrial device and its application (e.g., a robot and / or other wireless device operating in the context of an industrial and / or automated processing chain), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. As an example, the apparatus 20 may be implemented in, for example, a wireless handheld device, a wireless plug-in accessory, etc.

[0087] In some example embodiments, the apparatus 20 may include one or more processors, one or more computer-readable storage media (e.g., memory, storage device, etc.), one or more radio access components (e.g., modems, transceivers, etc.), and / or a user interface. In some embodiments, the apparatus 20 may be configured to operate using one or more radio access technologies, such as GSM, LTE, LTE-A, NR, 5G, WLAN, WiFi, NB-IoT, Bluetooth, NFC, MulteFire, and / or any other radio access technology. It should be noted that one of ordinary skill in the art will appreciate that the apparatus 20 may include Figure 6Components or features not shown.

[0088] like Figure 6 As shown in the example of , the device 20 may include or be coupled to a processor 22 for processing information and executing instructions or operations. The processor 22 may be any type of general or special purpose processor. In fact, as examples, the processor 22 may include one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and a processor based on a multi-core processor architecture. Although Figure 6 A single processor 22 is shown in FIG. 1 , but multiple processors may be utilized according to other embodiments. For example, it should be understood that in some embodiments, the apparatus 20 may include two or more processors that may form a multiprocessor system that may support multiprocessing (e.g., in which case the processor 22 may represent a multiprocessor). In some embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

[0089] As some examples, processor 22 may perform functions associated with the operation of device 20, including precoding of antenna gain / phase parameters, encoding and decoding of individual bits that form communication messages, formatting of information, and overall control of device 20, including processes related to management of communication resources.

[0090] The device 20 may also include or be coupled to a memory 24 (internal or external), which may be coupled to the processor 22 for storing information and instructions that may be executed by the processor 22. The memory 24 may be one or more memories and of any type suitable for the local application environment, and may be implemented using any suitable volatile or non-volatile data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and / or removable memory. For example, the memory 24 may include any combination of random access memory (RAM), read-only memory (ROM), static storage devices such as magnetic disks or optical disks, hard disk drives (HDDs), or any other type of non-transitory machine or computer-readable media. The instructions stored in the memory 24 may include program instructions or computer program code that, when executed by the processor 22, enables the device 20 to perform tasks as described herein.

[0091] In an embodiment, the device 20 may also include or be coupled to a (internal or external) drive or port configured to accept and read an external computer-readable storage medium, such as an optical disk, a USB drive, a flash drive, or any other storage medium. For example, the external computer-readable storage medium may store a computer program or software for execution by the processor 22 and / or the device 20.

[0092] In some embodiments, the device 20 may also include or be coupled to one or more antennas 25 for receiving downlink signals and transmitting from the device 20 via an uplink. The device 20 may also include a transceiver 28 configured to send and receive information. The transceiver 28 may also include a radio interface (e.g., a modem) coupled to the antenna 25. The radio interface may correspond to a variety of radio access technologies, including one or more of GSM, LTE, LTE-A, 5G, NR, WLAN, NB-IoT, Bluetooth, BT-LE, NFC, RFID, UWB, etc. The radio interface may include other components, such as filters, converters (e.g., digital-to-analog converters, etc.), symbol demappers, signal shaping components, inverse fast Fourier transform (IFFT) modules, etc., to process symbols carried by the downlink or uplink, such as OFDM symbols.

[0093] For example, the transceiver 28 may be configured to modulate information onto a carrier waveform for transmission by the antenna 25, and demodulate information received via the antenna 25 for further processing by other elements of the device 20. In other embodiments, the transceiver 28 is capable of directly sending and receiving signals or data. Additionally or alternatively, in some embodiments, the device 20 may include input and / or output devices (I / O devices). In some embodiments, the device 20 may also include a user interface, such as a graphical user interface or a touch screen.

[0094] In an embodiment, the memory 24 stores software modules that provide functionality when executed by the processor 22. These modules may include, for example, an operating system that provides operating system functionality for the device 20. The memory may also store one or more functional modules, such as applications or programs, to provide additional functionality to the device 20. The components of the device 20 may be implemented in hardware or any suitable combination of hardware and software. According to an example embodiment, the device 20 may optionally be configured to communicate with the device 10 via a wireless or wired communication link 70 according to any radio access technology (such as NR).

[0095] According to some embodiments, processor 22 and memory 24 may be included in or may form part of processing circuitry or control circuitry. In addition, in some embodiments, transceiver 28 may be included in or may form part of transceiver circuitry.

[0096] As described above, according to some embodiments, the apparatus 20 may be, for example, a UE, a SL UE, a relay UE, a mobile device, a mobile station, a ME, an IoT device, and / or a NB-IoT device, etc. According to some embodiments, the apparatus 20 may be controlled by the memory 24 and the processor 22 to perform functions associated with any of the embodiments described herein, such as Figures 2 to 5 shown in or relative to Figures 2 to 5 One or more of the operations described, or any other method described herein. For example, in one embodiment, the apparatus 20 may be controlled to perform a process related to providing a handover interruption duration reduction by receiving data on a source cell during a handover process, as described in detail elsewhere herein.

[0097] In some embodiments, an apparatus (e.g., apparatus 10 and / or apparatus 20) may include a component for performing a method, process, or any variation discussed herein. Examples of such components may include one or more processors, memories, controllers, transmitters, receivers, and / or computer program codes for enabling execution of any operation discussed herein.

[0098] In view of the foregoing, certain example embodiments provide several technical improvements, enhancements and / or advantages over prior art processes and constitute at least an improvement in the technical field of wireless network control and / or management. Certain embodiments may have various benefits and / or advantages. For example, certain embodiments may support operation of 5MHz UEs with configurations of CORESETs wider than 5MHz by using a supplemental CORESET. In addition, certain embodiments may support being able to overcome the loss of frequency diversity for PDCCH in the supplemental CORESET, which may occur with some configurations of CCE to REG mapping through configurable REG offsets. Two parameters and n offset The characteristics of BW reduction for eRedCap UE can be captured.

[0099] In some example embodiments, the functionality of any method, process, signaling diagram, algorithm, or flow chart described herein may be implemented by software and / or computer program code or portions of code stored in a memory or other computer-readable or tangible medium and executed by a processor.

[0100] In some example embodiments, a device may include or be associated with at least one software application, module, unit, or entity, which is configured as (multiple) arithmetic operations, or is configured as a program or part of a program (including added or updated software routines), which can be executed by at least one operation processor or controller. Programs (also referred to as program products or computer programs, including software routines, applets, and macros) can be stored in any device-readable data storage medium and may include program instructions for performing specific tasks. Computer program products may include one or more computer executable components that are configured to perform some example embodiments when the program is running. One or more computer executable components may be at least one software code or part of a code. Modifications and configurations required to implement the functions of the example embodiments may be performed as (multiple) routines, which may be implemented as (multiple) software routines added or updated. In one example, (multiple) software programs may be downloaded to the device.

[0101] As an example, software or computer program code or portions of code may be in source code form, object code form, or some intermediate form, and may be stored in some carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers may include, for example, recording media, computer memory, read-only memory, optoelectronic and / or electrical carrier signals, telecommunication signals, and / or software distribution packages. Depending on the processing power required, the computer program may be executed in a single electronic digital computer, or may be distributed among multiple computers. The computer readable medium or computer readable storage medium may be a non-transitory medium.

[0102] In other example embodiments, the functions of the example embodiments may be performed by hardware or circuitry included in a device, such as by using an application specific integrated circuit (ASIC), a programmable gate array (PGA), a field programmable gate array (FPGA), or any other combination of hardware and software. In yet another example embodiment, the functions of the example embodiments may be implemented as a signal carried by an electromagnetic signal downloaded from the Internet or other network, such as a non-tangible component.

[0103] According to example embodiments, an apparatus such as a node, a device or a corresponding component may be configured as a circuit system, a computer or a microprocessor (such as a single-chip computer element) or a chipset, which may include at least a memory for providing storage capacity for (multiple) arithmetic operations and / or an operation processor for performing (multiple) arithmetic operations.

[0104] The example embodiments described herein may apply to both singular and plural implementations, regardless of whether singular or plural language is used in conjunction with describing certain embodiments. For example, an embodiment describing the operation of a single network node may also apply to example embodiments including instances of multiple network nodes, and vice versa.

[0105] Those skilled in the art will readily appreciate that the example embodiments described above may be practiced with processes in a different order and / or with hardware elements in a configuration different from that disclosed. Therefore, although some embodiments have been described based on these example embodiments, it will be apparent to those skilled in the art that certain modifications, variations, and alternative configurations will be apparent while remaining within the spirit and scope of the example embodiments.

[0106] Partial glossary: HO Handover UP User Plane CP Control Plane RACH Random Access Channel gNB Next generation Node B. L1 Layer 1 L2 Layer 2 CU Central Unit DU Distributed Unit CHO condition switching MAC Media Access Control PS Probabilistic Scheduler CFRA Contention-free random access RACH Random Access Channel UE User Equipment NG Next Generation

Claims

1. A terminal device, comprising: at least one processor; as well as At least one memory stores instructions, and when the instructions are executed by the at least one processor, the terminal device at least executes: receiving a gap allocation configuration from a network; as well as Preparations are made for handover to a target cell during the gap according to the gap allocation.

2. The terminal device of claim 1, wherein the receiving the gap allocation further comprises receiving a timing advance configuration to obtain a timing advance for the target cell.

3. The terminal device according to claim 2, wherein when the instruction is executed by the at least one processor, the terminal device further causes the terminal device to at least execute: The timing advance configuration is used to receive a timing advance from the target cell over the allocated gap.

4. The terminal device according to claim 2, wherein the instruction further causes the terminal device to execute: Upon receiving the timing advance, a validity timer associated with the timing advance is started.

5. The terminal device according to claim 4, wherein the instruction further causes the terminal device to execute: The invalidation of the timing advance is indicated to the network upon expiration of a validity timer.

6. The terminal device according to claim 4 or 5, wherein the instruction further causes the terminal device to execute: An identity of the target cell to which the timing advance acquisition or further timing advance acquisition is applicable is received from the network.

7. A terminal device as claimed in any one of claims 4 to 6, wherein a dedicated random access channel opportunity or preamble allocation is provided with the timing advance configuration to accommodate timing advance acquisition.

8. The terminal device according to any one of claims 1 to 7, wherein the instruction further causes the terminal device to execute: An identification of a target cell is provided to the network, wherein the gap allocation is configured based on the target cell identified to the network.

9. The terminal device of any one of claims 1 to 8, wherein the gap allocation configuration comprises a mapping option regarding gap lengths.

10. The terminal device according to claim 9, wherein when the instructions are executed by the at least one processor, the terminal device is further caused to execute at least: An indication of a valid mapping option among the mapping options is received, wherein the preparing for the switching is performed based on the indication of the valid mapping option.

11. The terminal device according to claim 9 or 10, wherein the gap allocation configuration further comprises synchronization information about possible handover candidates.

12. The terminal device according to any one of claims 1 to 11, wherein the preparing comprises performing synchronization with the target cell before being handed over to the target cell.

13. The terminal device according to any one of claims 1 to 12, configured to use the gap to search for a random access channel opportunity of the target cell.

14. The terminal device according to any one of claims 1 to 13, configured to use the gap to perform a random access procedure with the target cell.

15. The terminal device of claim 14 in combination with claims 12 and 13, configured to indicate to a source node that a source cell can initiate the handover and can stop user plane procedures.

16. An apparatus comprising: at least one processor; as well as at least one memory storing instructions, which when executed by the at least one processor cause the apparatus to at least perform: determining that the user equipment will undergo a handover to a target cell; obtaining a gap allocation to be configured to the user equipment based on the determining; as well as The interval allocation is configured to the user equipment.

17. The apparatus of claim 16, wherein the obtaining comprises obtaining the gap allocation from a source distributed unit or from a peer base station.

18. The apparatus according to claim 16 or 17, wherein the configuring the gap allocation to the user equipment further comprises: Timing advance acquisition for the target cell is configured for the user equipment.

19. The apparatus of claim 18, wherein the instructions further cause the apparatus to: receiving an indication of invalidity of the timing advance from the user equipment; and In response to the indication, the user equipment is instructed to obtain the additional timing advance from the target cell.

20. The apparatus of claim 18 or 19, wherein the instructions further cause the apparatus to execute: The target cell to which the timing advance acquisition or another timing advance acquisition is applicable is identified to the user equipment.

21. The apparatus of any one of claims 18 to 20, wherein dedicated random access channel opportunities or preamble allocations are provided to accommodate timing advance acquisition.

22. The apparatus of any one of claims 16 to 21, wherein the instructions further cause the apparatus to execute: An identification of a target cell is received from the user equipment, wherein the interval allocation is configured according to the target cell identified by the user equipment.

23. A method comprising: receiving, at a terminal device, a gap allocation configuration from a network; as well as Preparation is made by the terminal device for handover to a target cell during the gap according to the gap allocation.

24. A method comprising: determining, at an access network element, that the user equipment will undergo a handover to a target cell; Obtaining, by the access network element based on the determination, a gap allocation to be configured for the user equipment; The access network element configures the gap allocation to the user equipment.

25. A terminal device, comprising: means for receiving a gap allocation configuration from a network; as well as Means for preparing for a handover to a target cell during the gap in accordance with the gap allocation.

26. An apparatus comprising: means for determining that the user equipment is to undergo a handover to a target cell; means for obtaining a gap allocation to be configured to the user equipment based on the determining; as well as Means for configuring the gap allocation to the user equipment.

27. A computer program product encoding instructions for executing the method of claim 23 or claim 24.

28. A circuit system for executing the method of claim 23 or 24.

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