Terminal device, communication device, and methods thereof

Abstract

Embodiments of the present disclosure relate to a communication method, an apparatus, and a computer-readable medium. A terminal device receives information associated with a lower layer signaling-based cell switch and determines, based on the information, whether a set of procedures is to be performed during the lower layer signaling-based cell switch. The set of procedures includes at least one of PDCP restoration for a set of DRBs, PDCP SDU discard for a set of SRBs, RRC re-establishment for a set of DRBs and a set of SRBs, or MAC reset. In this way, the terminal device may determine whether to perform or skip some L2 procedures for a subsequent lower layer-based mobility procedure.

Description

[Technical Field]

[0001] FIELD Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly to methods, apparatus, and computer storage media for communications based on lower layer signaling. [Background technology]

[0002] When a user equipment (UE) moves from the coverage area of ​​one cell to the coverage area of ​​another cell, it may be necessary to perform a change, addition, or release of the serving cell. Currently, it has been proposed to trigger the change, addition, or release of the serving cell by lower layer signaling, such as Layer 1 (L1) or Layer 2 (L2) signaling. In one solution, upon receiving lower layer signaling, the serving cell is changed and data transmission is performed, which is also called a lower layer-based mobility procedure. In this way, it is possible to reduce delay, overhead, and interruption time. However, the solution for the lower layer-based mobility procedure is still incomplete and needs further research. Summary of the Invention [Problem to be solved by the invention]

[0003] Generally, the exemplary embodiments of the present disclosure provide a method, apparatus, and computer storage medium for communications based on lower layer signaling. [Means for solving the problem]

[0004] In a first aspect, there is provided a method of communication, the method comprising: receiving, at a terminal device, information associated with a lower layer signaling based cell switch from a network device; and determining, based on the information, whether a set of procedures is to be performed during the lower layer signaling based cell switch, the set of procedures comprising at least one of a Packet Data Convergence Protocol restoration for a set of data radio bearers, a Packet Data Convergence Protocol service data unit discard for a set of signaling radio bearers, a Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or a Media Access Control reset.

[0005] In a second aspect, there is provided a method of communication, the method comprising: receiving, at a terminal device, lower layer signaling from a network device indicating a cell switch to a target cell; and transmitting, to the network device, an indication indicating completion of the cell switch, the indication including information of the target cell.

[0006] In a third aspect, there is provided a method of communication, the method comprising: transmitting, in a network device, information associated with lower layer signaling based cell switch, to a terminal device, the information for determining whether a set of procedures is to be performed during the lower layer signaling based cell switch, the set of procedures comprising at least one of: Packet Data Convergence Protocol restoration for a set of data radio bearers, Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers, Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or Media Access Control reset.

[0007] In a fourth aspect, there is provided a method of communication, the method including: transmitting, in a network device, lower layer signaling indicating a cell switch to a target cell to a terminal device; and receiving, from the terminal device, an indication indicating completion of the cell switch, the indication including information of the target cell.

[0008] In a fifth aspect, there is provided a communications apparatus, the apparatus comprising a processor configured to cause the apparatus to perform a method according to any one of the first or fourth aspects of the present disclosure.

[0009] In a sixth aspect, there is provided a computer-readable medium storing instructions that, when executed on at least one processor, cause the at least one processor to perform a method according to any one of the first to fourth aspects of the present disclosure.

[0010] Other features of the present disclosure will be readily apparent from the following description. [Brief explanation of the drawings]

[0011] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description of several embodiments of the present disclosure in the accompanying drawings.

[0012] [Figure 1A] FIG. 1 illustrates an exemplary communication network in which some embodiments of the present disclosure may be implemented.

[0013] [Figure 1B] 1 is a schematic diagram illustrating network protocol layer entities that may be established for a User Plane (UP) protocol stack in an apparatus according to some embodiments of the present disclosure. FIG.

[0014] [Figure 1C]1 is a schematic diagram illustrating network protocol layer entities that may be established for a control plane (CP) protocol stack in an apparatus according to some embodiments of the present disclosure.

[0015] [Figure 1D] 1 is a schematic diagram of a central unit (CU) / distributed unit (DU) architecture in which some embodiments of the present disclosure can be implemented.

[0016] [Figure 1E] FIG. 1 is a schematic diagram illustrating a process of lower layer-based mobility in which some embodiments of the present disclosure can be implemented.

[0017] [Figure 2] FIG. 1 is a schematic diagram illustrating a communication process according to an embodiment of the present disclosure.

[0018] [Figure 3A] FIG. 2 is a schematic diagram illustrating an example communication process based on lower layer signaling indicating a cell switch, according to an embodiment of the present disclosure.

[0019] [Figure 3B] FIG. 1 is a schematic diagram illustrating an exemplary communication process based on a configuration for lower layer signaling-based cell switching, according to an embodiment of the present disclosure.

[0020] [Figure 4] FIG. 10 is a schematic diagram of another communication process according to an embodiment of the present disclosure.

[0021] [Figure 5A] FIG. 2 is a schematic diagram illustrating an exemplary communication process based on lower layer signaling, according to an embodiment of the present disclosure.

[0022] [Figure 5B]1 is a schematic diagram illustrating an example communication process based on Radio Resource Control (RRC) signaling, according to an embodiment of the present disclosure.

[0023] [Figure 6] FIG. 1 illustrates an exemplary communication method implemented in a terminal device, according to some embodiments of the present disclosure.

[0024] [Figure 7] FIG. 10 illustrates another exemplary communication method implemented in a terminal device, according to some embodiments of the present disclosure.

[0025] [Figure 8] FIG. 1 illustrates an exemplary communication method implemented in a network device, in accordance with some embodiments of the present disclosure.

[0026] [Figure 9] FIG. 1 illustrates another exemplary communication method implemented in a network device, in accordance with some embodiments of the present disclosure.

[0027] [Figure 10] FIG. 1 is a schematic block diagram of an apparatus suitable for implementing embodiments of the present disclosure.

[0028] In the drawings, the same or similar reference numbers represent the same or similar elements. DETAILED DESCRIPTION OF THE INVENTION

[0029] The principles of the present disclosure will now be described with reference to some embodiments. It should be understood that these embodiments are provided for illustrative purposes only to assist those skilled in the art in understanding and practicing the present disclosure, and do not imply any limitation on the scope of the present disclosure. The disclosure described herein can be implemented in various ways different from those described below.

[0030] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0031] As used herein, the term "terminal device" refers to any device with wireless or wired communication capabilities. Examples of terminal devices include User Equipment (UE), personal computers, desktops, mobile phones, cellular phones, smartphones, Personal Digital Assistants (PDAs), portable computers, tablets, wearable devices, Internet of Things (IoT) devices, Ultra-reliable and Low Latency Communication (URLLC) devices, Internet of Everything (IoE) devices, Machine Type Communication (MTC) devices, vehicle-mounted devices for V2X communications (where X stands for pedestrian, vehicle, or infrastructure / network), devices for Integrated Access and Backhaul (IAB), satellite- or airborne vehicles in a Non-Terrestrial Network (NTN) including High Altitude Platforms (HAPs) including satellites and Unmanned Aircraft Systems (UASs), Augmented Reality (AR), Mixed Reality (MR), and other technologies. This includes, but is not limited to, extended reality (XR) devices that include different types of reality, such as virtual reality (VR), unmanned aerial vehicles (UAVs), which are aircraft without a human pilot and are commonly referred to as drones, devices on high-speed trains (HSTs), image capture devices such as digital cameras, sensors, gaming devices, music storage and playback devices, or internet devices that enable wireless or wired internet access and browsing.A "terminal device" may further have "multicast / broadcast" capabilities to support public safety and mission-critical, V2X applications, transparent IPv4 / IPv6 multicast distribution, IPTV, smart TV, wireless services, over-the-air software distribution, group communication, and IoT applications. It may also incorporate one or more Subscriber Identity Modules (SIMs), known as multi-SIM. The term "terminal device" may be used interchangeably with UE, mobile station, subscriber station, mobile terminal, user terminal, or wireless device.

[0032] The term "network device" refers to a device that can provide or host a cell or coverage area in which a terminal device can communicate. Examples of network devices include, but are not limited to, a Node B (Node B or NB), an evolved Node B (eNode B or eNB), a next generation Node B (gNB), a Transmission Reception Point (TRP), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), an IAB node, a low-power node such as a femto node or a pico node, a Reconfigurable Intelligent Surface (RIS), etc.

[0033] The terminal device or network device may have the capability of artificial intelligence (AI) or machine learning, which generally includes a model trained from a large amount of data collected for a specific function and can be used to predict some information.

[0034] The terminal device or network device may operate on several frequency ranges, such as FR1 (410 MHz to 7125 MHz), FR2 (24.25 GHz to 71 GHz), frequency bands greater than 100 GHz, and Terahertz (THz). It can also operate on licensed, unlicensed, and shared spectrum. The terminal device may have two or more connections with the network device under a Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or network device can operate in full duplex, flexible duplex, and cross-division duplex modes.

[0035] Embodiments of the present disclosure may be implemented in test equipment, such as, for example, a signal generator, a signal analyzer, a spectrum analyzer, a network analyzer, a test terminal device, a test network device, a channel emulator, and the like.

[0036] In one embodiment, a terminal device may be connected to a first network device and a second network device. One of the first network device and the second network device may be a master node, and the other may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs). In one embodiment, the first network device may be a first RAT device, and the second network device may be a second RAT device. In one embodiment, the first RAT device is an eNB, and the second RAT device is a gNB. Information regarding different RATs may be transmitted to the terminal device from at least one of the first network device or the second network device. In one embodiment, the first information may be transmitted from the first network device to the terminal device, and the second information may be transmitted from the second network device directly or via the first network device to the terminal device. In one embodiment, information regarding the terminal device configuration configured by the second network device may be transmitted from the second network device via the first network device. The information regarding the reconfiguration of the terminal device configured by the second network device may be transmitted to the terminal device directly from the second network device or via the first network device.

[0037] As used herein, the singular forms "a / an" and "the" include the plural forms unless the context clearly indicates otherwise. The term "comprises" and variations thereof should be understood as open-ended terms meaning "including, but not limited to." The term "based on" should be understood as "based at least in part on." The terms "one embodiment" and "embodiment" should be understood as "at least one embodiment." The term "another embodiment" should be understood as "at least one other embodiment." Terms such as "first," "second," etc. may refer to different or the same object. The following may include other explicit and implicit definitions.

[0038] In some instances, values, procedures, or devices are referred to as "best," "lowest," "highest," "minimum," "maximum," etc. It should be understood that such descriptions are intended to illustrate that choices may be made from among many functional alternatives used, and that such choices are not necessarily better, smaller, higher, or otherwise more preferred than other choices.

[0039] In the context of the present disclosure, the term "cell switch" may be used interchangeably with "reconfiguration with synchronization for a Secondary Cell Group (SCG) or Master Cell Group (MCG)" or "cell change." The term "PSCell" refers to an SpCell of an SCG, the term "PCell" refers to an SpCell of an MCG, and the term "SpCell" refers to a primary cell of an SCG or MCG. The term "SCell" refers to a secondary cell. The term "L1 / L2-based mobility" may be used interchangeably with "L1 / L2-triggered mobility" or "L1-triggered mobility" or "L2-triggered mobility" (abbreviated as LTM). The term "lower layer signaling" may be used interchangeably with "L1 / L2 signaling." The term "RRC reconfiguration" may be used interchangeably with "RRC reconfiguration message." The term "data transmission" refers to the transmission and reception of data.

[0040] As mentioned above, when a UE moves from the coverage area of ​​one cell to the coverage area of ​​another cell, it may be necessary to perform a serving cell change, addition, or release. Traditionally, serving cell change, addition, or release is performed by a synchronized reconfiguration triggered by Layer 3 (L3) measurements and, for primary cell (PCell) and primary secondary cell (PSCell) changes, triggered by RRC signaling. All cases involve a full L2 and L1 reset, which causes longer latency, more overhead, and longer disruption than beam switching mobility.

[0041] It has been proposed to trigger cell switching based on lower layer signaling, e.g., L1 or L2 signaling, thus reducing delay, overhead, and interruption time. However, there are still some problems during lower layer signaling-based cell switching.

[0042] In a conventional handover or PSCell change, whether to perform L2 procedures, such as Packet Data Convergence Protocol (PDCP) recovery, PDCP Service Data Unit (SDU) discard, and Radio Link Control (RLC) re-establishment, is based on the received RRCReconfiguration, and Medium Access Control (MAC) reset is always performed. In the case of lower layer-based mobility procedures, some of the L2 procedures may be omitted for intra-distributed unit (intra-DU) mobility scenarios. However, because the UE trace is unpredictable, it is impossible to configure whether some of the L2 procedures are performed. Furthermore, it is unclear which one or more of the L2 procedures can be omitted.

[0043] In view of this, embodiments of the present disclosure provide a communication solution to overcome the above problems and other potential problems, in which a network device transmits information associated with lower layer signaling-based cell switching, and based on the information, a terminal device determines whether to perform a set of procedures, including at least one of PDCP restoration for a set of data radio bearers (DRBs), PDCP SDU discard for a set of signaling radio bearers (SRBs), RLC re-establishment for a set of DRBs and a set of SRBs, or MAC reset.

[0044] In this way, the terminal device may decide whether to perform or skip some L2 procedures for subsequent lower layer based mobility procedures (i.e., subsequent LTMs).

[0045] Furthermore, in the case of conventional mobility procedures, when a handover or PSCell change is performed, the UE generates an RRCReconfigurationComplete message as a completion indication to the network. However, it is still unclear whether the configuration for each candidate cell includes an RRCReconfiguration message. If there is no RRCReconfiguration message for each candidate cell, the question is what to use as a response to the network as a completion indication.

[0046] In view of this, embodiments of the present disclosure provide another communication solution to overcome this and other potential problems, in which a terminal device receives lower layer signaling from a network device indicating a cell switch to a target cell, and transmits an indication to the network device indicating completion of the cell switch, the indication including information of the target cell, so that the network can know the completion or confirmation of the lower layer-based mobility.

[0047] The principles and embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Example of a communication network

[0048] 1A shows a schematic diagram illustrating an exemplary communication network 100A in which some embodiments of the present disclosure can be implemented. As shown in FIG. 1A, communication network 100A may include terminal device 110 and multiple network devices 120 and 130 (also referred to herein as network device 120 and network device 130 for convenience). Network devices 120 and 130 provide respective cells 121 and 131 to serve the terminal device.

[0049] 1A is provided for illustrative purposes only and should not be construed as a limitation on the present disclosure. Communication network 100A may include any suitable number of network devices and / or terminal devices suitable for implementing embodiments of the present disclosure. Furthermore, each of network devices 120 and 130 may provide more cells to terminal device 110.

[0050] 1A, terminal device 110 may communicate with network device 120 or 130 via a channel, such as a wireless communication channel. Communications in communication network 100A may conform to any suitable standard, including, but not limited to, Global System for Mobile Communications (GSM), Long Term Evolution (LTE), LTE-Evolution, LTE-Advanced (LTE-A), New Radio (NR), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), Machine Type Communication (MTC), etc. Embodiments of the present disclosure may be performed in accordance with any generation of communication protocols now known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or sixth generation (6G) networks.

[0051] Communication in the direction from terminal device 110 to network device 120 or 130 is referred to as uplink (UL) communication, and communication in the reverse direction from network device 120 or 130 to terminal device 110 is referred to as downlink (DL) communication. Terminal device 110 may travel between cells of network devices 120, 130, and possibly other network devices. In UL communication, terminal device 110 may transmit UL data and control information to network device 120 or 130 over a UL channel. In DL communication, network device 120 or 130 may transmit DL data and control information to terminal device 110 over a DL channel.

[0052] Communications in the communication network 100A may be performed according to UP and CP protocol stacks. Generally speaking, for a communication device (e.g., a terminal device or a network device), there may be multiple entities at multiple network protocol layers in the protocol stack, and these entities may be configured to perform corresponding processes on data or signaling transmitted from and received by the communication device. FIG. 1B is a schematic diagram 100B illustrating network protocol layer entities that may be established for a UP protocol stack in an apparatus according to some embodiments of the present disclosure. For convenience, the following description will be given taking communication between a terminal device 110 and a network device 120 as an example. It should be understood that the following description is also applicable to communication between a terminal device 110 and a network device 130.

[0053] In some embodiments, network devices 120 and 130 may be different network devices. In some embodiments, network devices 120 and 130 may be the same network device.

[0054] 1B , in the UP, each of the terminal device 110 and the network device 120 may include an L1 layer entity, i.e., a physical (PHY) layer entity (also referred to as a PHY entity), and one or more entities of an upper layer (L2 layer and Layer 3 (L3) layer, or higher layer), including a MAC layer entity (also referred to as a MAC entity), an RLC layer entity (also referred to as an RLC entity), a PDCP layer entity (also referred to as a PDCP entity), and a Service Data Application Protocol (SDAP) layer entity (also referred to as an SDAP entity, which will be established in 5G and later generation networks). In some cases, the PHY, MAC, RLC, PDCP, and SDAP entities have a stack structure.

[0055] FIG. 1C is a schematic diagram 100C illustrating network protocol layer entities that may be established for a CP protocol stack in an apparatus according to some embodiments of the present disclosure. As shown in FIG. 1C, in a CP, each of the terminal device 110 and the network device 120 may include an L1 layer entity, i.e., a PHY layer entity (also referred to as a PHY entity), and one or more entities of higher layers (L2 layer and L3 layer), including a MAC layer entity (also referred to as a MAC entity), an RLC layer entity (also referred to as an RLC entity), a PDCP layer entity (also referred to as a PDCP entity), and a Radio Resource Control (RRC) layer entity (also referred to as an RRC entity). The RRC layer may also be referred to as an Access Stratum (AS) layer, and therefore, the RRC entity may also be referred to as an AS entity. As shown in FIG. 1C, the terminal device 110 may also include a Non-Access Stratum (NAS) layer entity (also referred to as a NAS entity). The NAS layer on the network side is located in a core network (CN, not shown) rather than in a network device. In some cases, these entities are in a stack structure.

[0056] In the context of this disclosure, L1 refers to the PHY layer, L2 refers to the MAC or RLC or PDCP or SDAP layer, and L3 refers to the RRC layer. In the context of this disclosure, L1 or L2 may collectively be referred to as a lower layer, and L3 may be referred to as an upper layer. Thus, L1 or L2 signaling may be referred to as lower layer signaling, and L3 signaling may be referred to as upper layer signaling.

[0057] Generally, communication channels are divided into logical channels, transmission channels, and physical channels. Physical channels are channels through which the PHY layer actually transmits information. For example, physical channels may include a Physical Uplink Control Channel (PUCCH), a Physical Uplink Shared Channel (PUSCH), a Physical Random-Access Channel (PRACH), a PDCCH, a Physical Downlink Shared Channel (PDSCH), and a Physical Broadcast Channel (PBCH).

[0058] The transmission channel is a channel between the PHY layer and the MAC layer, and may include, for example, a Broadcast Channel (BCH), a Downlink Shared Channel (DL-SCH), a Paging Channel (PCH), an Uplink Shared Channel (UL-SCH), and a Random Access Channel (RACH).

[0059] Logical channels are channels between the MAC layer and the RLC layer, and may include, for example, a Dedicated Control Channel (DCCH), a Common Control Channel (CCCH), a Paging Control Channel (PCCH), a Broadcast Control Channel (BCCH), and a Dedicated Traffic Channel (DTCH).

[0060] Generally, a channel between the RRC layer and the PDCP layer is referred to as a radio bearer. The terminal device 110 may be configured with at least one data radio bearer (DRB) for carrying data plane data and at least one signaling radio bearer (SRB) for carrying control plane data. Four types of SRBs, SRB0, SRB1, SRB2, and SRB3, may be defined in the RRC layer. SRB0 uses the CCCH for establishing or re-establishing an RRC connection. SRB1 uses the DCCH and is established when an RRC connection is established. SRB2 uses the DCCH and is established during RRC re-configuration and after initial security activation. SRB3 uses the DCCH and is established between the terminal device 110 and the SN when a dual connection is established.

[0061] 1D is a schematic diagram 100D illustrating a CU / DU architecture in which some embodiments of the present disclosure can be implemented. The CU / DU architecture may be established in a network device.

[0062] In the context of this disclosure, a CU (also referred to herein as a gNB-CU) is a logical node that hosts the RRC, SDAP, and PDCP protocols of a gNB or the RRC and PDCP protocols of an en-gNB, which controls the operation of one or more DUs (also referred to herein as a gNB-DU). The gNB-CU terminates the F1 interface connected to the gNB-DU. A DU is a logical node that hosts the RLC, MAC, and PHY layers of a gNB or an en-gNB, and its operation is partially controlled by the gNB-CU. One gNB-DU supports one or more cells. One cell is supported by only one gNB-DU. The gNB-DU terminates the F1 interface connected to the gNB-CU.

[0063] As shown in FIG. 1D, CU 141 is shown. It should be understood that more CUs may be included. CU 141 may communicate with multiple DUs. Here, for illustration purposes, two DUs 151 and 152 are shown. More DUs may be provided for implementing embodiments of the present disclosure. Although not shown, CU 141 may be responsible for performing the functions of an SDAP entity and a PDCP entity, and DU 151 or 152 may be responsible for performing the functions of an RLC entity, a MAC entity, and a PHY entity.

[0064] DU 151 may serve cells 161, 162, and 163. DU 152 may serve cells 164, 165, and 166. It should be understood that this is just one example and any more or fewer cells are possible. Terminal device 110 may communicate with any of these cells.

[0065] In some embodiments, the terminal device 110 may switch from one cell to another cell under the control of the same CU and the same DU. For example, the terminal device 110 may be handed over from one cell 161 to another cell 162. This is referred to as an intra-CU, intra-DU serving cell switch. In some embodiments, the terminal device 110 may switch from one cell to another cell under the control of the same CU and a different DU. For example, the terminal device 110 may be handed over from one cell 161 to another cell 164. In this case, a cell switch occurs from one cell of DU 151 to another cell of DU 152. This is referred to as an intra-CU, inter-DU serving cell switch. In another example, the terminal device 110 may be handed over from a cell of one DU to a cell of another DU under the control of a different CU. In this case, a handover occurs from a CU to another CU. This is referred to as an inter-CU handover.

[0066] Network device 120 and network device 130 may correspond to one or two devices under the same CU. In some embodiments, the CU and DU may be implemented in separate devices. In some embodiments, the CU and DU may be implemented in the same device. In some embodiments, different DUs may be implemented in separate devices.

[0067] 1A , in some embodiments, terminal device 110 may be located within the coverage of cell 121 of network device 120, and terminal device 110 may communicate with network device 120 based on a network configuration. In this case, cell 121 may be referred to as a serving cell of terminal device 110.

[0068] In some embodiments, terminal device 110 may establish a dual connection (i.e., a simultaneous connection) with network device 120 and another network device (not shown). In some embodiments, network device 120 may function as a master node (MN). In these embodiments, terminal device 110 may communicate with network device 120 via a set of serving cells. The set of serving cells constitutes an MCG, and a primary cell within the MCG is referred to as a PCell. In some scenarios, the PCell may change from cell 121 to cell 131, which is referred to as a handover. In some embodiments, network device 120 may function as a secondary node (SN). In these embodiments, the set of serving cells provided by network device 120 forms an SCG, and a primary cell within the SCG is referred to as a PSCell. In some scenarios, the PSCell may change from cell 121 to cell 131, which is referred to as a PScell ​​change.

[0069] In some scenarios, terminal device 110 may receive L1 or L2 signaling indicating the addition, modification, or release of a serving cell from network device 120. Upon the addition, modification, or release of the serving cell, terminal device 110 may perform data transmission involving the addition, modification, or change of the serving cell. This procedure is referred to as lower layer-based mobility.

[0070] FIG. 1E is a schematic diagram illustrating a process 100E for lower layer-based mobility in which some embodiments of the present disclosure can be implemented. For illustrative purposes, process 100E will be described with reference to FIG. 1A. Process 100E may involve terminal device 110 and network device 120 as shown in FIG. 1A. Network device 120 may be an MN or SN serving terminal device 110. In this example, network device 120 provides a serving cell for terminal device 110. Network device 130 does not provide a serving cell for terminal device 110.

[0071] 1E, network device 120 may transmit an RRC reconfiguration including a set of RRC configurations corresponding to a set of candidate cells that enable L1 / L2-based mobility to terminal device 110 (170). Network device 120 may also transmit beam configurations (e.g., synchronization signals and physical broadcast channel blocks (SSBs) or channel state information-reference signals (CSI-RSs)) of the candidate cells for L1 measurements to terminal device 110 (171).

[0072] The terminal device 110 may perform L1 measurements based on the configuration (172). If a condition is met by a beam, for example, if the quality of the beam is above a threshold quality, the terminal device 110 may report an indication of the beam (e.g., an identity (ID) associated with the beam) to the network device 120 (173).

[0073] The network device 120 may send 174 L1 / L2 signaling (e.g., Downlink Control Information (DCI) or Medium Access Control (MAC) Control Element (CE)) to the terminal device 110, indicating that a Transmission Configuration Indicator (TCI) state for one of the candidate cells has been activated due to the cell switch.

[0074] Upon receiving the L1 / L2 signaling, the terminal device 110 may perform a cell switch (175). For example, a lower layer (e.g., a PHY or MAC layer) of the terminal device 110 indicates information of the cell switch, such as an ID associated with the target cell, to the RRC layer of the terminal device 110. The L1 / L2 signaling may also indicate that a TCI state for a cell with a different physical cell identifier (PCI) has been activated along with the cell switch. Upon receiving the indication, the RRC layer applies a configuration corresponding to the target cell and performs the cell switch. The target cell may be a PCell, PSCell, or SCell of the terminal device 110. The terminal device 110 may start data transmission with the target cell using a preconfigured UE-dedicated channel and the activated TCI state.

[0075] In the case of lower layer-based mobility, some L2 procedures may be omitted for intra-DU mobility scenarios to reduce mobility delay. However, since the UE trace is unpredictable, it is impossible to configure whether some L2 procedures will be performed. Furthermore, it is unclear which one or more of the L2 procedures can be omitted.

[0076] The embodiments of the present disclosure provide a solution for indicating whether to perform some L2 procedures, which will be described in detail with reference to Figures 2 to 3B. Example of implementation of decision whether to perform L2 procedure

[0077] 2 is a schematic diagram illustrating a communication process 200 according to an embodiment of the present disclosure. For purposes of explanation, the process 200 will be described with reference to FIG. 1A. The process 200 may involve a terminal device 110 and a network device 120 as shown in FIG. 1A. In this example, the network device 120 serves the terminal device 110.

[0078] 2, network device 120 may transmit 210 information associated with lower-layer signaling-based cell switch (i.e., lower-layer-based mobility) to terminal device 110. In some embodiments, the information may include information (also referred to herein as first information for convenience) regarding whether to perform a set of procedures for lower-layer signaling-based cell switch. In some embodiments, the information may include information (also referred to herein as second information for convenience) for assisting terminal device 110 in determining whether to perform a set of procedures for lower-layer signaling-based cell switch.

[0079] 2 , based on the first information or the second information, terminal device 110 determines whether the set of procedures is to be performed for the lower layer signaling-based cell switch (220). In some embodiments, the set of procedures may include PDCP SDU discarding for a set of SRBs. For example, for the set of SRBs, the PDCP entity of terminal device 110 may discard all stored PDCP SDUs and PDCP protocol data units (PDUs).

[0080] In some alternative or additional embodiments, the set of procedures may include PDCP restoration for a set of DRBs. In some alternative or additional embodiments, the set of procedures may include RLC re-establishment for a set of DRBs and a set of SRBs. In some alternative or additional embodiments, the set of procedures may include MAC reset. It should be understood that the set of procedures may include any combination of the above procedures and any other suitable procedures. In some embodiments, the set of procedures may be referred to as an L2 reset procedure.

[0081] In some embodiments where the set of procedures is not performed, terminal device 110 may perform an LTM-specific MAC reset (also referred to herein as a partial MAC reset). In some embodiments of an LTM-specific MAC reset, terminal device 110 may continue data transmission and reception processing-related procedures at the MAC layer and perform at least one of the following operations: · Do not reset Bj of each logical channel to zero / Maintain Bj of each logical channel; Do not cancel / keep triggered Scheduling Request procedures; Do not cancel / maintain triggered Buffer Status Reporting procedures, · Not clearing / maintaining buffers for all Hybrid Automatic Repeat Request (HARQ) processes; Do not set the New Data Indicator (NDI) to 0 for all uplink HARQ processes / keep NDI for all HARQ processes, or -Do not consider the timeAlignmentTimer of any Timing Advance Group (TAG) as expired / Maintain the timeAlignmentTimer of all TAGs.

[0082] In some alternative embodiments of an LTM-specific MAC reset, terminal device 110 may perform at least one of the following operations: Stop all timers (if they are running), Stopping ongoing Random Access (RA) procedures, if any exist; Discarding explicitly signaled conflict-free RA resources between 4-step and 2-step RA types, if they exist; Flushing the Msg3 buffer, Flushing the MSGA buffer, Canceling a triggered Power Headroom Reporting procedure, if any; Cancelling triggered continuous Listen Before Talk (LBT) faults, if any, Canceling triggered Beam Failure Reports (BFRs), if any; Cancelling a triggered Recommended Bit Rate query procedure, if any; Canceling the triggered configured uplink authorization check, if any; Canceling a triggered Desired Guard Symbol query, if any; Releasing a temporary Cell-Radio Network Temporary Identifier (C-RNTI), if present; Reset all Beam Failure Instance (BFI) counters, or Reset all LBT_COUNTERs.

[0083] For illustrative purposes, some exemplary embodiments are described in relation to embodiment 1 and embodiment 2. Embodiment 1

[0084] In this embodiment, the network device 120 may send the first information in lower layer signaling indicating a cell switch. In some embodiments, the lower layer signaling may be a MAC CE. In some embodiments, the lower layer signaling may be a DCI. For illustrative purposes, a detailed description is provided in connection with FIG. 3A.

[0085] 3A is a schematic diagram illustrating an example communication process 300A based on lower layer signaling indicating a cell switch, according to an embodiment of the present disclosure. For illustrative purposes, process 300A will be described with reference to FIG. 1A. Process 300A may involve terminal device 110 and network device 120 as shown in FIG. 1A. In this example, network device 120 serves terminal device 110.

[0086] 3A, network device 120 may transmit lower layer signaling indicating a cell switch to terminal device 110 (310). In some embodiments, a CU (e.g., CU 141) of network device 120 may transmit an indication to a source DU (e.g., DU 151) of network device 120 indicating whether the set of procedures is to be performed. Based on the indication, the source DU may generate lower layer signaling indicating a cell switch. The source DU may transmit the generated lower layer signaling to terminal device 110.

[0087] The lower layer signaling includes first information regarding whether to execute the set of procedures for the lower layer signaling-based cell switch. In some embodiments, the lower layer signaling may be MAC CE. In some embodiments, the lower layer signaling may be DCI.

[0088] In some embodiments, the first information may include an indication indicating whether the set of procedures is to be performed. In some embodiments, the indication may include a single indication regarding whether all procedures in the set of procedures are to be performed. In some embodiments, the indication may include a set of instructions, where an indication in the set of instructions indicates whether a procedure in the set of procedures is to be performed.

[0089] In some alternative or additional embodiments, the first information may include an indication indicating a mobility scenario of the cell switch.

[0090] Referring to FIG. 3A, the terminal device 110 may determine whether to perform the set of procedures for the cell switch based on the first information (320).

[0091] In some embodiments in which the first information includes an indication of whether the set of procedures is to be performed, if the indication indicates that the set of procedures is not to be performed, terminal device 110 may determine that the set of procedures is not to be performed. If the indication indicates that the set of procedures is to be performed, terminal device 110 may determine that the set of procedures is to be performed.

[0092] In some embodiments in which the first information includes an indication of a mobility scenario of a cell switch, if the mobility scenario of the cell switch is an intra-CU, intra-DU scenario, the terminal device 110 may determine that the set of procedures is not to be performed. If the mobility scenario of the cell switch is an intra-CU, inter-DU scenario, the terminal device 110 may determine that the set of procedures is to be performed.

[0093] In some embodiments, upon receiving the first information, a lower layer (e.g., a MAC layer) of terminal device 110 may send an indication to a higher layer (e.g., an RRC, PDCP, and RLC layer) of terminal device 110 indicating that the set of procedures is to be performed. The higher layer may perform the set of procedures. In some embodiments, upon receiving the first information, a lower layer may send an indication to the higher layer indicating whether the set of procedures is to be performed. The higher layer may perform or skip the set of procedures based on the indication from the lower layer.

[0094] In some embodiments, upon receiving the first information, the lower layers of terminal device 110 may send an indication to the RRC layer, which may instruct the lower layers (PDCP, RLC, and MAC layers) to perform or skip the set of procedures. In some embodiments, the lower layers of terminal device 110 may send an indication directly to the PDCP and RLC layers, which perform or skip the set of procedures accordingly based on the indication from the lower layers (e.g., the MAC layer).

[0095] Thus, the terminal device may decide whether to perform or skip some L2 procedures for subsequent lower layer based mobility. Embodiment 2

[0096] In this embodiment, the network device 120 may transmit the second information within a configuration for lower layer signaling-based cell switching. In some embodiments, the network device 120 may transmit the configuration for lower layer signaling-based cell switching within an RRC message, where the configuration includes assistance information (i.e., the second information) for the terminal device 110 to determine whether to perform the set of procedures. For illustrative purposes, a detailed description will be provided in connection with FIG. 3B.

[0097] 3B is a schematic diagram illustrating an example communication process 300B based on a configuration for lower layer signaling-based cell switching, according to an embodiment of the present disclosure. For illustrative purposes, process 300B will be described with reference to FIG. 1A. Process 300B may involve terminal device 110 and network device 120 as shown in FIG. 1A. In this example, network device 120 serves terminal device 110.

[0098] 3B, the network device 120 may send 330 a configuration for lower layer signaling-based cell switching to the terminal device 110. The configuration includes second information.

[0099] In some embodiments, the second information may include information (eg, identity) of a DU or cell group associated with a candidate cell in the set of candidate cells.

[0100] In some embodiments, the second information may include an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell to another second candidate cell of the set of candidate cells. For example, the second information may include a plurality of lists, each list of the plurality of lists indicating, for a candidate cell, whether the set of procedures is to be performed during a cell switch from the candidate cell to each of the other candidate cells.

[0101] In some embodiments, the second information may include an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures. For example, the second information may include a plurality of lists, each list of the plurality of lists indicating, for a candidate cell, one or more cell switches from the candidate cell to other candidate cells that do not require execution of the set of procedures.

[0102] In some embodiments, the second information may include an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that requires execution of the set of procedures. For example, the second information may include a plurality of lists, each list of the plurality of lists indicating, for a candidate cell, one or more cell switches from the candidate cell to other candidate cells that require execution of the set of procedures.

[0103] 3B , the network device 120 may further transmit lower layer signaling indicating a cell switch to the terminal device 110 (340). In this case, the terminal device 110 may determine whether to execute the set of procedures for the cell switch based on the second information (350).

[0104] In some embodiments, where the second information includes information of a DU or cell group associated with a candidate cell from the set of candidate cells, if the target cell and the source cell associated with the cell switch are associated with different DUs or cell groups, the terminal device 110 may determine that the set of procedures is to be performed. If the target cell and the source cell are associated with the same DU or cell group, the terminal device 110 may determine that the set of procedures is not to be performed.

[0105] In some embodiments in which the second information includes an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell to another second candidate cell in the set of candidate cells, terminal device 110 may determine, based on the indication, whether the set of procedures is to be performed during a cell switch from a source cell to a target cell. If the set of procedures is indicated as being performed during a cell switch, terminal device 110 may determine that the set of procedures is to be performed. If the set of procedures is not indicated as being performed during a cell switch, terminal device 110 may determine that the set of procedures is not to be performed.

[0106] In some embodiments, where the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures, if the second information includes an indication of a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is not to be executed.If the second information does not include an indication of a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is to be executed.

[0107] In some embodiments, where the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells, which requires execution of the set of procedures, if the second information includes an indication of a cell switch from a source cell to a target cell, terminal device 110 may determine that the set of procedures is to be executed. If the second information does not include an indication of a cell switch from a source cell to a target cell, terminal device 110 may determine that the set of procedures is not to be executed.

[0108] In some embodiments, if the configuration does not include the second information, terminal device 110 may determine that the set of procedures is to be performed.

[0109] In some embodiments, terminal device 110 may determine, based on the second information, whether the set of procedures is to be performed for a subsequent cell switch. In some embodiments, terminal device 110 may determine, based on the second information, whether the set of procedures is to be performed for a first cell switch after receiving an RRC reconfiguration for LTM. In some embodiments, terminal device 110 may determine, based on a recoverPDCP information element (IE), a discardOnPDCP IE, and a reestablishRLC IE included in a configuration associated with a target candidate cell, whether the set of procedures is to be performed for a first cell switch after receiving an RRC reconfiguration for LTM.

[0110] In this way, the terminal device may still decide whether to perform or skip some L2 procedures for subsequent lower layer-based mobility. Example Implementation of Lower Layer-Based Mobility Completion Indication

[0111] As mentioned above, it is still unclear whether the configuration for each candidate cell includes an RRCReconfiguration message. In the absence of an RRCReconfiguration message for each candidate cell, the question is what is used as a response to the network as a completion indication.

[0112] In view of this, embodiments of the present disclosure provide a solution for indicating completion of lower layer-based mobility by a terminal device, which will be described below in connection with FIG.

[0113] 4 is a schematic diagram illustrating another communication process 400 according to an embodiment of the present disclosure. For illustrative purposes, the process 400 will be described with reference to FIG. 1A. The process 400 may involve a terminal device 110 and a network device 120 as shown in FIG. 1A. In this example, the network device 120 serves the terminal device 110.

[0114] As shown in Figure 4, network device 120 transmits 410 lower layer signaling to terminal device 110 indicating a cell switch to the target cell. In some embodiments, the lower layer signaling may be a MAC CE. In some embodiments, the lower layer signaling may be a MAC CE with a fixed size of zero bits. In some embodiments, the lower layer signaling may be a DCI.

[0115] Continuing with reference to FIG. 4, the terminal device 110 transmits (420) an indication to the network device 120 indicating completion of the cell switch, the indication including information about the target cell.

[0116] In some embodiments, terminal device 110 may transmit another lower layer signaling including the indication. In some embodiments, the other lower layer signaling may be a MAC CE. In some embodiments, the other lower layer signaling may be a MAC CE with a fixed size of zero bits. In some embodiments, the other lower layer signaling may be a DCI.

[0117] In some embodiments, terminal device 110 may transmit RRC signaling including the indication. In some embodiments, the RRC signaling may be an RRC Reconfiguration Complete message.

[0118] In some embodiments, the target cell information may include an identity of the target cell. In some embodiments, the target cell information may include an identity of a lower layer signaling-based cell switching configuration associated with the target cell. It should be understood that any combination of the above information and any other suitable information is possible.

[0119] For illustrative purposes, some exemplary embodiments are described in relation to embodiment 3 and embodiment 4. Embodiment 3

[0120] In this embodiment, the terminal device 110 may transmit lower layer signaling including an indication indicating the completion of the cell switch. For illustrative purposes, a detailed description is provided in connection with FIG. 5A.

[0121] 5A is a schematic diagram illustrating an example communication process 500A based on lower layer signaling according to an embodiment of the present disclosure. For illustrative purposes, the process 500A will be described with reference to FIG. 1D. The process 500A may involve the terminal device 110, the CU 141, and the DUs 151 and 152 as shown in FIG. 1D. In this example, the DU 151 serves the terminal device 110 and functions as a source DU, and the DU 152 does not serve the terminal device 110 and functions as a target DU.

[0122] As shown in FIG. 5A, the DU 151 transmits (510) lower layer signaling to the terminal device 110 indicating a cell switch to a target cell (e.g., the cell 164 of the DU 152). In some embodiments, the lower layer signaling may be a MAC CE. In some embodiments, the lower layer signaling may be a MAC CE with a fixed size of zero bits. In some embodiments, the lower layer signaling may be a DCI.

[0123] Continuing with reference to FIG. 5A, the terminal device 110 transmits (520) another lower layer signaling to the DU 152 indicating completion of the cell switch. The another lower layer signaling includes information of the target cell. In some embodiments, the another lower layer signaling may be a MAC CE. In some embodiments, the another lower layer signaling may be a MAC CE with a fixed size of zero bits. In some embodiments, the another lower layer signaling may be a DCI.

[0124] The DU 152 transmits information indicating the completion of the cell switch to the CU 141 (530). The information includes information of the target cell. In some embodiments, the information of the target cell may include an identity of the target cell. In some embodiments, the information of the target cell may include an identity of a lower layer signaling-based cell switch configuration associated with the target cell. It should be understood that any combination of the above information and any other suitable information is possible.

[0125] In this way, the network can know the completion or confirmation of mobility on a lower layer basis. Embodiment 4

[0126] In this embodiment, the terminal device 110 may transmit RRC signaling including an indication indicating the completion of the cell switch. For illustrative purposes, a detailed description is provided in connection with FIG.

[0127] 5B is a schematic diagram illustrating an example communication process 500B based on RRC signaling according to an embodiment of the present disclosure. For illustrative purposes, the process 500B will be described with reference to FIG. 1D. The process 500B may involve the terminal device 110, the CU 141, and the DUs 151 and 152 as shown in FIG. 1D. In this example, the DU 151 serves the terminal device 110 and functions as a source DU, and the DU 152 does not serve the terminal device 110 and functions as a target DU.

[0128] As shown in FIG. 5B, the DU 151 transmits (540) lower layer signaling to the terminal device 110 indicating a cell switch to a target cell (e.g., cell 164 of the DU 152). In some embodiments, the lower layer signaling may be a MAC CE. In some embodiments, the lower layer signaling may be a MAC CE with a fixed size of zero bits. In some embodiments, the lower layer signaling may be a DCI.

[0129] 5B, the terminal device 110 transmits RRC signaling indicating the completion of the cell switch to the CU 141 via the DU 152 (550). That is, the terminal device 110 may transmit the RRC signaling to the DU 152, and the DU 152 may forward the RRC signaling to the CU 141.

[0130] The RRC signaling may include target cell information. In some embodiments, the target cell information may include a target cell identity. In some embodiments, the target cell information may include a lower layer signaling-based cell switching configuration identity associated with the target cell. It should be understood that any combination of the above information and any other suitable information is possible.

[0131] This still allows the network to know of the completion or confirmation of mobility on a lower layer basis. Example implementation of the method

[0132] Therefore, embodiments of the present disclosure provide communication methods implemented in a terminal device and a network device, which are described below with reference to Figures 6 to 9.

[0133] 6 illustrates an exemplary communication method 600 implemented in a terminal device, according to some embodiments of the present disclosure. For example, method 600 may be performed in terminal device 110 as shown in FIG. 1A. For purposes of explanation, method 600 will be described below with reference to FIG. 1A. It should be understood that method 600 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0134] In block 610, the terminal device 110 receives information regarding lower layer signaling-based cell switching from the network device 120.

[0135] In some embodiments, terminal device 110 may receive lower layer signaling indicating a cell switch, the lower layer signaling including first information regarding whether to perform the set of procedures for the lower layer signaling-based cell switch. In some embodiments, the first information may include an indication indicating whether the set of procedures is to be performed. In some embodiments, the first information may include an indication indicating a mobility scenario for the cell switch.

[0136] In some embodiments, the terminal device 110 may receive a configuration for a lower layer signaling-based cell switch, the configuration including second information for assisting the terminal device in determining whether to execute the set of procedures for the lower layer signaling-based cell switch. In some embodiments, the second information may include an indication of a DU associated with a candidate cell of a set of candidate cells. In some embodiments, the second information may include an indication as to whether the set of procedures is to be executed during a cell switch from one candidate cell to another candidate cell of the set of candidate cells. In some embodiments, the second information may include an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures. In some embodiments, the second information may include an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that requires execution of the set of procedures.

[0137] In block 620, the terminal device 110 determines, based on the information, whether a set of procedures is to be performed during the lower layer signaling-based cell switch, the set of procedures including at least one of: Packet Data Convergence Protocol restoration for the set of data radio bearers, Packet Data Convergence Protocol service data unit discard for the set of signaling radio bearers, Radio Link Control re-establishment for the set of data radio bearers and the set of signaling radio bearers, or Media Access Control reset.

[0138] In some embodiments in which the first information includes an indication of whether the set of procedures is to be performed, if the indication indicates that the set of procedures is not to be performed, terminal device 110 may determine that the set of procedures is not to be performed. If the indication indicates that the set of procedures is to be performed, terminal device 110 may determine that the set of procedures is to be performed.

[0139] In some embodiments in which the first information includes an indication of a mobility scenario of the cell switch, if the mobility scenario of the cell switch is an intra-CU and intra-DU scenario, the terminal device 110 may determine that the set of procedures is not to be performed. If the mobility scenario of the cell switch is an intra-CU and inter-DU scenario, the terminal device 110 may determine that the set of procedures is to be performed.

[0140] In some embodiments, terminal device 110 may send an indication indicating that the set of procedures is to be performed from a lower layer of terminal device 110 to a higher layer of terminal device 110. The higher layer may perform the set of procedures.

[0141] In some embodiments, where the second information includes information of a distributed unit associated with a candidate cell of the set of candidate cells, if the target cell and the source cell are associated with different DUs, the terminal device 110 may determine that the set of procedures is to be performed. If the target cell and the source cell are associated with the same DU, the terminal device 110 may determine that the set of procedures is not to be performed.

[0142] In some embodiments in which the second information includes an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell to another second candidate cell of the set of candidate cells, if the set of procedures is to be performed during a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is to be performed. If the set of procedures is not to be performed during a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is not to be performed.

[0143] In some embodiments, where the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures, if the second information includes an indication of a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is not to be executed.If the second information does not include an indication of a cell switch from the source cell to the target cell, terminal device 110 may determine that the set of procedures is to be executed.

[0144] In some embodiments, where the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells, which requires execution of the set of procedures, if the second information includes an indication of a cell switch from a source cell to a target cell, terminal device 110 may determine that the set of procedures is to be executed. If the second information does not include an indication of a cell switch from a source cell to a target cell, terminal device 110 may determine that the set of procedures is not to be executed.

[0145] In some embodiments in which a configuration for lower layer signaling-based cell switching is received, if the configuration does not include the second information, the terminal device may determine that the set of procedures is to be executed.

[0146] Method 600 may allow the terminal device to determine whether to perform or skip some L2 procedures for subsequent lower layer based mobility procedures.

[0147] 7 illustrates an exemplary communication method 700 implemented in a terminal device according to some embodiments of the present disclosure. For example, method 700 may be performed in terminal device 110 as shown in FIG. 1A. For purposes of explanation, method 700 will be described below with reference to FIG. 1A. It should be understood that method 700 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0148] In block 710, the terminal device 110 receives lower layer signaling from the network device 120 indicating a cell switch to the target cell.

[0149] In block 720, the terminal device 110 sends an indication to the network device 120 indicating completion of the cell switch, the indication including the target cell information.

[0150] In some embodiments, the terminal device 110 may transmit another lower layer signaling including the instruction to a DU of the network device 120 associated with the target cell for transmission of the target cell information to a CU of the network device 120.

[0151] In some embodiments, the terminal device 110 may transmit RRC signaling including the indication. In some embodiments, the terminal device 110 may transmit the RRC signaling to a CU of the network device 120 via a DU of the network device 120 associated with the target cell.

[0152] In some embodiments, the information of the target cell may include at least one of an identity of the target cell or an identity of a lower layer signaling-based cell switching configuration associated with the target cell.

[0153] The method 700 allows the network to know the completion or confirmation of lower layer based mobility.

[0154] 8 illustrates an exemplary communication method 800 implemented in a network device according to some embodiments of the present disclosure. For example, method 800 may be performed in network device 120 as shown in FIG. 1A. For purposes of explanation, method 800 will be described below with reference to FIG. 1A. It should be understood that method 800 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0155] In block 810, the network device 120 transmits to the terminal device 110 information associated with a lower layer signaling based cell switch, the information for determining whether a set of procedures is to be performed during the lower layer signaling based cell switch, the set of procedures including at least one of a packet data convergence protocol restoration for a set of data radio bearers, a packet data convergence protocol service data unit discard for a set of signaling radio bearers, a radio link control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or a media access control reset.

[0156] In some embodiments, the network device 120 may transmit lower layer signaling indicating a cell switch, the lower layer signaling including first information regarding whether to perform the set of procedures for the lower layer signaling-based cell switch. In some embodiments, the first information may include at least one of an indication indicating whether the set of procedures is to be performed or an indication indicating a mobility scenario of the cell switch.

[0157] In some embodiments, the network device 120 may transmit a configuration for lower layer signaling-based cell switch, the configuration including second information for assisting the terminal device in determining whether to execute the set of procedures for the lower layer signaling-based cell switch. In some embodiments, the second information may include at least one of: information of a distribution unit associated with a candidate cell of a set of candidate cells; an indication as to whether the set of procedures is to be executed during cell switch from one candidate cell to another candidate cell of the set of candidate cells; an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures; or an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that requires execution of the set of procedures.

[0158] In some embodiments, network device 120 may transmit the configuration for the lower layer signaling based cell switch without including information related to the lower layer signaling based cell switch.

[0159] According to the method 800, the network device may prompt the terminal device to decide whether to perform or skip some L2 procedures for subsequent lower layer based mobility procedures.

[0160] 9 illustrates an exemplary communication method 900 implemented in a network device according to some embodiments of the present disclosure. For example, method 900 may be performed in network device 120 as shown in FIG. 1A. For purposes of explanation, method 900 will be described below with reference to FIG. 1A. It should be understood that method 900 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0161] In block 910, the network device 120 sends lower layer signaling to the terminal device 110 indicating a cell switch to the target cell.

[0162] In block 920, the network device 120 receives an indication from the terminal device 110 indicating completion of the cell switch, the indication including information about the target cell.

[0163] In some embodiments, the network device 120 may receive another lower layer signaling including an indication, and in some embodiments, the network device 120 may receive the other lower layer signaling at a DU of the network device 120 associated with the target cell, and transmit information indicating completion of the cell switch, the information including information of the target cell, at the DU to a CU of the network device.

[0164] In some embodiments, network device 120 may receive RRC signaling including the indication. In some embodiments, network device 120 may receive the RRC signaling at a DU of network device 120 and forward the RRC signaling to a CU of network device 120 by the DU.

[0165] In some embodiments, the information of the target cell includes at least one of an identity of the target cell or an identity of a lower layer signaling-based cell switching configuration associated with the target cell.

[0166] It should be noted that the operations of methods 600-900 are similar to those described in connection with FIGS. 2-5B, and therefore other details will not be repeated here for the sake of brevity. Device and equipment implementation examples

[0167] 10 is a schematic block diagram of an apparatus 1000 suitable for implementing an embodiment of the present disclosure. The apparatus 1000 can be considered as another exemplary implementation of the terminal apparatus 110 or the network apparatus 120 shown in FIG. 1A, or the CU 141, the DU 151, or the DU 152 shown in FIG. 1D. Thus, the apparatus 1000 can be implemented in or as at least a part of the terminal apparatus 110, the network apparatus 120, the CU 141, or the DU 151 or 152.

[0168] As shown, the apparatus 1000 comprises a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transmitter (TX) and receiver (RX) 1040 coupled to the processor 1010, and a communication interface coupled to the TX / RX 1040. The memory 1010 stores at least a portion of a program 1030. The TX / RX 1040 is used for bidirectional communication. The TX / RX 1040 has at least one antenna to facilitate communication, although the access nodes referred to herein may in practice have multiple antennas. The communication interface may represent any interface required for communication with other network elements, such as an X2 / Xn interface for bidirectional communication between eNBs / gNBs, an S1 / NG interface for communication between a Mobility Management Entity (MME) / Access and Mobility Management Function (AMF) / SGW / UPF and an eNB / gNB, an Un interface for communication between an eNB / gNB and a Relay Node (RN), or a Uu interface for communication between an eNB / gNB and a terminal device.

[0169] The program 1030 is assumed to include program instructions that, when executed by an associated processor 1010, enable the device 1000 to operate according to embodiments of the present disclosure, as described herein with reference to Figures 2-9. The embodiments herein may be implemented by computer software executable by the processor 1010 of the device 1000, by hardware, or by a combination of software and hardware. The processor 1010 may be configured to implement various embodiments of the present disclosure. Furthermore, the combination of the processor 1010 and the memory 1020 may form a processing means 1050 suitable for implementing various embodiments of the present disclosure.

[0170] The memory 1020 may be of any type suitable for a local technology network and may be implemented using any suitable data storage technology, including, by way of non-limiting example, non-transitory computer-readable storage media, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. While only one memory 1020 is shown in the device 1000, there may be several physically distinct memory modules within the device 1000. The processor 1010 may be of any type suitable for a local technology network and may include, by way of non-limiting example, one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. The device 1000 may have multiple processors, for example, application-specific integrated circuit chips time-slaved to a clock that synchronizes the main processor.

[0171] In some embodiments, a terminal device comprises circuitry configured to receive information associated with a lower layer signaling based cell switch from a network device and to determine, based on the information, whether a set of procedures is to be performed during the lower layer signaling based cell switch, the set of procedures including at least one of a Packet Data Convergence Protocol restoration for a set of data radio bearers, a Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers, a Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or a Media Access Control reset.

[0172] In some embodiments, a terminal device comprises circuitry configured to receive lower layer signaling from a network device indicating a cell switch to a target cell, and to transmit to the network device an indication indicating completion of the cell switch, the indication including information about the target cell.

[0173] In some embodiments, the network device comprises circuitry configured to transmit to a terminal device information associated with lower layer signaling based cell switching, the information for determining whether a set of procedures is to be performed during the lower layer signaling based cell switching, the set of procedures comprising at least one of: Packet Data Convergence Protocol restoration for a set of data radio bearers; Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers; Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers; or Media Access Control reset.

[0174] In some embodiments, the network device comprises circuitry configured to send lower layer signaling to a terminal device indicating a cell switch to a target cell, and to receive from the terminal device an indication indicating completion of the cell switch, the indication including information about the target cell.

[0175] As used herein, the term "circuitry" may refer to a hardware circuit and / or a combination of a hardware circuit and software. For example, a circuit may be a combination of analog and / or digital hardware circuitry and software / firmware. As yet another example, a circuit may be any portion of a hardware processor with software, including a digital signal processor, software, and memory, that cooperate to cause a device, such as a terminal device or a network device, to perform various functions. In yet another example, a circuit may be a hardware circuit and / or a processor, such as a microprocessor or portion thereof, that requires software / firmware for operation, although software may not be present if not necessary for operation. As used herein, the term "circuitry" also includes implementations of a hardware circuit or one or more processors only, or a hardware circuit or portion of one or more processors and its (or their) accompanying software and / or firmware.

[0176] In summary, the embodiments of the present disclosure can provide the following solutions:

[0177] In one solution, a method of communication includes receiving, in a terminal device, information associated with a lower layer signaling based cell switch from a network device, and determining based on the information whether a set of procedures is to be performed during the lower layer signaling based cell switch, the set of procedures including at least one of: Packet Data Convergence Protocol restoration for a set of data radio bearers, Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers, Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or Media Access Control reset.

[0178] In some embodiments, receiving the information includes receiving, at the terminal device, lower layer signaling from the network device indicating a cell switch, the lower layer signaling including first information regarding whether to execute the set of procedures for the lower layer signaling-based cell switch.

[0179] In some embodiments, the first information includes an indication of whether the set of procedures is to be performed. In these embodiments, determining whether the set of procedures is to be performed includes determining that the set of procedures is not to be performed in accordance with a determination that the indication indicates that the set of procedures is not to be performed, or determining that the set of procedures is to be performed in accordance with a determination that the indication indicates that the set of procedures is to be performed.

[0180] In some embodiments, the first information includes an indication of a mobility scenario of a cell switch. In these embodiments, determining whether the set of procedures is to be performed includes determining that the set of procedures is not to be performed in accordance with determining that the mobility scenario of the cell switch is an intra-centralized-unit and intra-distributed-unit scenario, or determining that the set of procedures is to be performed in accordance with determining that the mobility scenario of the cell switch is an intra-centralized-unit and inter-distributed-unit scenario.

[0181] In some embodiments, the method further includes sending an indication from a lower layer of the terminal device to an upper layer of the terminal device indicating that the set of procedures is to be executed, and executing the set of procedures by the upper layer.

[0182] In some embodiments, receiving the information includes receiving, at the terminal device, a configuration for the lower layer signaling-based cell switch from the network device, the configuration including second information for assisting the terminal device in determining whether to perform the set of procedures for the lower layer signaling-based cell switch.

[0183] In some embodiments, the second information includes information of a distribution unit associated with a candidate cell of a set of candidate cells. In these embodiments, determining whether to perform the set of procedures includes determining to perform the set of procedures in accordance with a determination that the target cell and the source cell are associated with different distribution units, or determining not to perform the set of procedures in accordance with a determination that the target cell and the source cell are associated with the same distribution unit.

[0184] In some embodiments, the second information includes an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell to another second candidate cell of the set of candidate cells. In these embodiments, determining whether the set of procedures is to be performed includes determining that the set of procedures is to be performed in accordance with a determination that the set of procedures is to be performed during a cell switch from a source cell to a target cell, or determining that the set of procedures is not to be performed in accordance with a determination that the set of procedures is not to be performed during a cell switch from a source cell to a target cell.

[0185] In some embodiments, the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells that does not require execution of the set of procedures. In these embodiments, determining whether the set of procedures is to be executed includes determining that the set of procedures will not be executed in accordance with a determination that the second information includes an indication of a cell switch from a source cell to a target cell, or determining that the set of procedures will be executed in accordance with a determination that the second information does not include an indication of a cell switch from a source cell to a target cell.

[0186] In some embodiments, the second information includes an indication of a cell switch from one candidate cell to another candidate cell of the set of candidate cells, requiring execution of the set of procedures. In these embodiments, determining whether the set of procedures is to be executed includes determining that the set of procedures is to be executed in accordance with a determination that the second information includes an indication of a cell switch from a source cell to a target cell, or determining that the set of procedures is not to be executed in accordance with a determination that the second information does not include an indication of a cell switch from a source cell to a target cell.

[0187] In some embodiments, receiving the information further includes receiving, at the terminal device, a configuration for the lower layer signaling-based cell switching from the network device. In some embodiments, determining whether the set of procedures is to be performed includes determining that the set of procedures is to be performed in accordance with a determination that the configuration does not include the second information.

[0188] In another solution, a communication method includes receiving, in a terminal device, lower layer signaling from a network device indicating a cell switch to a target cell, and transmitting, to the network device, an indication indicating completion of the cell switch, the indication including information of the target cell.

[0189] In some embodiments, transmitting the indication comprises transmitting another lower layer signaling that includes the indication, or transmitting radio resource control signaling that includes the indication.

[0190] In some embodiments, transmitting the other lower layer signaling includes transmitting the other lower layer signaling to a distributed unit of the network equipment associated with the target cell for transmission of the information of the target cell to a centralized unit of the network equipment.

[0191] In some embodiments, transmitting the radio resource control signaling includes transmitting the radio resource control signaling to a centralized unit of the network equipment via a distributed unit of the network equipment associated with the target cell.

[0192] In some embodiments, the information of the target cell includes at least one of an identity of the target cell or an identity of a lower layer signaling-based cell switching configuration associated with the target cell.

[0193] In another solution, a method of communication includes transmitting, in a network device, information associated with a lower layer signaling based cell switch, the information for determining whether a set of procedures is to be performed during the lower layer signaling based cell switch, to a terminal device, the set of procedures including at least one of: Packet Data Convergence Protocol restoration for a set of data radio bearers, Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers, Radio Link Control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or Media Access Control reset.

[0194] In some embodiments, transmitting the information includes transmitting lower layer signaling indicating a cell switch, the lower layer signaling including first information regarding whether to perform the set of procedures for the lower layer signaling-based cell switch.

[0195] In some embodiments, the first information includes at least one of an indication indicating whether the set of procedures is performed or an indication indicating a mobility scenario of the cell switch.

[0196] In some embodiments, transmitting the information includes transmitting a configuration for the lower layer signaling-based cell switch, the configuration including second information for assisting the terminal device in determining whether to perform the set of procedures for the lower layer signaling-based cell switch.

[0197] In some embodiments, the second information includes at least one of: information of a distribution unit associated with a candidate cell of the set of candidate cells; an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell of the set of candidate cells to another second candidate cell; an indication for a cell switch from one candidate cell of the set of candidate cells to another candidate cell that does not require execution of the set of procedures; or an indication for a cell switch from one candidate cell of the set of candidate cells to another candidate cell that requires execution of the set of procedures.

[0198] In some embodiments, transmitting the information further comprises transmitting a configuration of the lower layer signaling based cell switching that does not include information related to the lower layer signaling based cell switching.

[0199] In another solution, a communication method includes transmitting, in a network device, lower layer signaling indicating a cell switch to a target cell to a terminal device, and receiving from the terminal device an indication indicating completion of the cell switch, the indication including information of the target cell.

[0200] In some embodiments, receiving the indication comprises receiving another lower layer signaling that includes the indication, or receiving radio resource control signaling that includes the indication.

[0201] In some embodiments, receiving the other lower layer signaling includes receiving the other lower layer signaling at a distributed unit of the network equipment associated with the target cell, and transmitting information indicating completion of the cell switch, the information including information of the target cell, to a centralized unit at the distributed unit of the network equipment.

[0202] In some embodiments, receiving the radio resource control signaling includes receiving the radio resource control signaling at a distributed unit of the network device and forwarding the radio resource control signaling by the distributed unit to a centralized unit of the network device.

[0203] In some embodiments, the information of the target cell includes at least one of an identity of the target cell or an identity of a lower layer signaling-based cell switching configuration associated with the target cell.

[0204] In another solution, a communication device comprises a processor configured to cause said device to perform any one of the above methods.

[0205] Overall, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software executable by a controller, microprocessor, or other computing device. While various aspects of embodiments of the present disclosure have been illustrated and described using block diagrams, flowcharts, or other pictorial representations, it should be understood that the blocks, devices, systems, techniques, or methods described herein may be implemented in, by way of non-limiting example, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing device, or any combination thereof.

[0206] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, that execute within a device on a target real or virtual processor to perform the processes or methods described above with reference to FIGS. 2-9. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split between program modules as desired. The machine-executable instructions of the program modules may be executed within local or distributed devices. In a distributed device, program modules may be located in both local and remote storage media.

[0207] Program code for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, and when executed by the processor or controller, cause the program code to implement the functions / acts specified in the flowcharts and / or block diagrams. The program code may run entirely on the machine, partially on the machine, as a separate software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0208] The above-described program code may be embodied on a machine-readable medium, which may be any tangible medium that can contain or store a program used by or associated with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the aforementioned media. More specific examples of a machine-readable storage medium may include an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0209] Although operations have been described in a particular order, it should not be understood that performing these operations in the particular order or sequence shown, or performing all of the operations described, is required to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular embodiments. Some features that are described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination.

[0210] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it should be understood that the present disclosure, as defined in the appended claims, is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method of communication comprising: receiving, at a terminal device, information associated with lower layer signaling-based cell switching from a network device; determining, based on the information, whether a set of procedures is to be performed during the lower layer signaling based cell switch; The set of steps comprises: Packet data convergence protocol recovery for a set of data radio bearers; Packet Data Convergence Protocol Service Data Unit discard for a set of signaling radio bearers; Radio link control re-establishment for a set of data radio bearers and a set of signaling radio bearers, or media access control reset method.

2. Receiving the information includes: receiving, at the terminal device, lower layer signaling indicating a cell switch from the network device, the lower layer signaling including first information regarding whether to execute the set of procedures for the lower layer signaling-based cell switch; The method of claim 1.

3. The first information includes an indication of whether the set of procedures is to be performed, and determining whether the set of procedures is to be performed includes: determining that the set of procedures is not to be performed in accordance with a determination that the instructions indicate that the set of procedures is not to be performed; or determining, in accordance with determining that the instructions indicate that the set of procedures is to be performed, that the set of procedures is to be performed. The method of claim 2.

4. The first information includes an indication indicating a cell switching mobility scenario, and determining whether the set of procedures is to be performed includes: determining that the set of procedures is not executed according to a determination that the mobility scenario of the cell switch is an intra-centralized unit and intra-distributed unit scenario; or determining that the set of procedures is to be performed according to a determination that the mobility scenario of the cell switching is an intra-centralized unit and inter-distributed unit scenario. The method of claim 2.

5. sending an indication from a lower layer of the terminal device to an upper layer of the terminal device indicating that the set of procedures is to be performed; executing the set of procedures by the upper layer; The method of claim 2 further comprising:

6. Receiving the information includes: and receiving, at the terminal device, a configuration for the lower layer signaling-based cell switch from the network device, the configuration including second information for assisting the terminal device in determining whether to execute the set of procedures for the lower layer signaling-based cell switch. The method of claim 1.

7. The second information includes information of a distribution unit associated with a candidate cell of a set of candidate cells, and determining whether the set of procedures is to be performed includes: determining that said set of procedures is to be performed in accordance with a determination that the target cell and the source cell are associated with different distribution units; or determining that the set of procedures is not to be performed in accordance with a determination that the target cell and the source cell are associated with the same distribution unit. The method of claim 6.

8. The second information includes an indication as to whether the set of procedures is to be performed during a cell switch from one candidate cell to another second candidate cell of a set of candidate cells, and determining whether the set of procedures is to be performed includes: determining that the set of procedures is to be performed in accordance with a determination that the set of procedures is to be performed during cell switching from a source cell to a target cell; or determining, in accordance with a determination that the set of procedures is not to be performed during a cell switch from a source cell to a target cell, that the set of procedures is not to be performed. The method of claim 6.

9. the second information includes an indication of a cell switch from one candidate cell to another candidate cell of a set of candidate cells that does not require execution of the set of procedures, and determining whether the set of procedures is to be executed includes: determining, in accordance with a determination that the second information includes an indication of a cell switch from a source cell to a target cell, that the set of procedures is not to be performed; or determining that the set of procedures is to be performed in accordance with a determination that the second information does not include an indication of a cell switch from a source cell to a target cell. The method of claim 6.

10. the second information includes an indication of a cell switch from one candidate cell to another candidate cell of a set of candidate cells, which requires execution of the set of procedures, and determining whether the set of procedures is to be executed includes: determining that the set of procedures is to be performed in accordance with a determination that the second information includes an indication of a cell switch from a source cell to a target cell; or determining, in accordance with a determination that the second information does not include an instruction for a cell switch from a source cell to a target cell, that the set of procedures is not to be performed. The method of claim 6.

11. Receiving the information further includes receiving, at the terminal device, a configuration for the lower layer signaling-based cell switching from the network device; Determining whether the set of procedures is to be performed includes determining that the set of procedures is to be performed in accordance with a determination that the configuration does not include the second information. The method of claim 6.

12. A method of communication comprising: receiving, at the terminal device, lower layer signaling from a network device indicating a cell switch to the target cell; sending an indication to the network device indicating completion of the cell switch, the indication including information of the target cell; A method comprising:

13. transmitting the instruction sending another lower layer signaling containing said indication; or transmitting radio resource control signaling including the indication. The method of claim 12.

14. transmitting the other lower layer signaling transmitting the further lower layer signaling to a distributed unit of the network equipment associated with the target cell for transmission of the information of the target cell to a centralized unit of the network equipment. The method of claim 13.

15. transmitting the radio resource control signaling transmitting the radio resource control signaling to a centralized unit of the network equipment via a distributed unit of the network equipment associated with the target cell. The method of claim 13.

16. The information of the target cell is: the identity of the target cell; or a lower layer signaling based cell switching configuration identity associated with the target cell. The method of claim 12.

17. A processor configured to cause a communication device to perform the method according to any one of claims 1 to 11 or any one of claims 12 to 16. Communication equipment.

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