Cell change method and device

Abstract

An embodiment of the present invention provides a cell change method and device, the method including: a terminal device sending measurement results to a first network node, the terminal device receiving L1 signaling and / or L2 signaling from the first network node, and the terminal device changing from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to the field of communications. [Background technology]

[0002] Network-controlled mobility applies to connected terminals and can be classified into two types of mobility: cell-level mobility and beam-level mobility.

[0003] Cell-level mobility must be triggered by explicit RRC signaling, i.e., handover. The RRC-triggered handover mechanism requires the UE to reset at least its MAC entity and re-establish RLC. RRC-managed handover is supported with or without re-establishment of the Packet Data Convergence Protocol (PDCP) entity. For data radio bearers (DRBs) using RLC AM mode, PDCP may be re-established with security key updating, or the data recovery process may be initiated without re-keying. For DRBs using RLC UM mode, PDCP may be re-established with security key updating, or it may be maintained without re-keying. For signaling radio bearers (SRBs), PDCP may be maintained without re-keying and stored PDCP PDUs / SDUs may be discarded, or it may be re-established with security key updating.

[0004] The above description of the background art is merely for the purpose of explaining the configuration of the present invention more clearly and completely, and is provided for the understanding of those skilled in the art. These configurations described in the background art of the present invention should not be construed as being well known to those skilled in the art. Summary of the Invention [Problem to be solved by the invention]

[0005] When a terminal moves from the coverage area of ​​one cell to the coverage area of ​​another cell, it will at some point need to perform a change of serving cell. Currently, the change of serving cell is triggered by L3 measurements and performed by RRC signaling, with triggered Reconfiguration with Synchronisation for the change of Primary Cell PCell and Primary Secondary Cell PSCell, and the release of Secondary Cell SCells if applicable.

[0006] Inter-cell mobility may include intra-gNB-DU mobility, intra-gNB-CU inter-gNB-DU mobility, and inter-gNB-CU mobility.

[0007] The intra-gNB-DU mobility procedure is used when a UE moves from one cell to another within the same gNB-DU or when an intra-cell handover is performed. This procedure is supported by the UE Context Modification (gNB-CU initiated) procedure.

[0008] When an intra-gNB-DU handover (inter-cell or intra-cell) is performed, the gNB-CU provides a channel with a UL GTP TEID for the gNB-DU, and the gNB-DU provides a new DL GTP TEID for the gNB-CU. The gNB-DU continues to transmit UL PDCP PDUs to the gNB-CU using the previous UL GTP TEID until RLC is re-established, and then starts transmitting using the new UL GTP TEID. The gNB-CU continues to transmit DL PDCP PDUs to the gNB-DU using the previous DL GTP TEID until PDCP re-establishment or PDCP data recovery is performed, and then starts transmitting using the new DL GTP TEID.

[0009] The intra-gNB-CU inter-gNB-DU mobility procedure is used when a terminal moves from one gNB-DU to another gNB-DU within the same gNB-CU.

[0010] 1 is a schematic diagram of an example of a mobility procedure between gNB-DU within a gNB-CU. As shown in FIG. 1, this procedure includes the following steps:

[0011] 1. The UE sends a Measurement Report message to the source gNB-DU.

[0012] 2. The source gNB-DU sends a UL RRC MESSAGE TRANSFER message to the gNB-CU to convey the received Measurement Report message.

[0013] 2a. The gNB-CU may send a UE CONTEXT MODIFICATION REQUEST message to the source gNB-DU to inquire about the latest configuration.

[0014] 2b. The source gNB-DU responds with a UE CONTEXT MODIFICATION RESPONSE message containing complete configuration information.

[0015] 3. The gNB-CU sends a UE CONTEXT SETUP REQUEST message to the target gNB-DU to create a UE context and establish one or more data bearers. The UE CONTEXT SETUP REQUEST message includes Handover Preparation Information. In the case of NG-RAN sharing, the gNB-CU includes the serving PLMN ID (in the case of an SNPN, the serving SNPN ID).

[0016] 4. The target gNB-DU responds to the gNB-CU with a UE CONTEXT SETUP RESPONSE message.

[0017] 5. The gNB-CU sends a UE CONTEXT MODIFICATION REQUEST message containing the generated RRC Reconfiguration message to the source gNB-DU to instruct the UE to stop data transmission. The source gNB-DU also sends a downlink data transmission status frame to notify the gNB-CU of the downlink data that failed to be transmitted to the UE.

[0018] Note: In the case of a DAPS handover, the UE CONTEXT MODIFICATION REQUEST message in step 5 may instruct only the DRB(s) not undergoing the DAPS handover to stop data transmission, or may not instruct the UE to stop data transmission at all. Alternatively, the DL RRC message transmission procedure may be used to send a handover command to the UE. Once the source gNB-CU knows that the UE has successfully accessed the target gNB-DU, it sends a UE CONTEXT MODIFICATION REQUEST message to the source gNB-DU indicating the UE's stopping of data transmission, and the source gNB-DU sends a DDDS frame regarding the failed downlink data transmission to the gNB-CU.

[0019] 6. The source gNB-DU forwards the received RRCReconfiguration message to the UE.

[0020] 7. The source gNB-DU responds to the gNB-CU with a UE CONTEXT MODIFICATION RESPONSE message.

[0021] 8. The target gNB-DU performs a random access procedure. The target gNB-DU sends a downlink data transmission status frame to notify the gNB-CU. A downlink packet, which may contain PDCP PDUs whose transmission failed in the source gNB-DU, is sent from the gNB-CU to the target gNB-DU.

[0022] Note: Whether the gNB-CU starts transmitting DL user data to the gNB-DU before or after receiving the downlink data transmission status depends on the implementation of the gNB-CU.

[0023] 9. The UE responds to the target gNB-DU with an RRCReconfigurationComplete message.

[0024] 10. The target gNB-DU sends a UL RRC MESSAGE TRANSFER message to the gNB-CU to convey the received RRCReconfigurationComplete message. Downlink packets are sent to the UE, and uplink packets are sent from the UE and forwarded to the gNB-CU via the target gNB-DU.

[0025] 11. The gNB-CU sends a UE CONTEXT RELEASE COMMAND message to the source gNB-DU.

[0026] 12. The source gNB-DU releases the UE context and responds to the gNB-CU with a UE CONTEXT RELEASE COMPLETE message.

[0027] 2 is a schematic diagram of an example of a signaling flow of mobility between gNB and CU. As shown in FIG. 2, this signaling flow includes the following steps:

[0028] 1. The source gNB initiates the handover and sends a HANDOVER REQUEST over the Xn interface.

[0029] 2. The target gNB performs admission control and provides the new RRC configuration as part of the HANDOVER REQUEST ACKNOWLEDGE.

[0030] 3. The source gNB provides the UE with RRC configuration by passing the RRC Reconfiguration message received in the HANDOVER REQUEST ACKNOWLEDGE. The RRC Reconfiguration message includes at least a cell ID and all information necessary to access the target cell so that the UE can access the target cell without reading system information. The information for accessing the target cell may include beam-specific information.

[0031] 4. The UE moves the RRC connection to the target gNB and responds with RRCReconfigurationComplete.

[0032] 3 is a schematic diagram of an example of a handover procedure within AMF / UPF. As shown in FIG. 3, this procedure includes the following steps:

[0033] 0. The UE context in the source gNB contains information about roaming and access restrictions, which information is provided at the time of connection establishment or the last TA update.

[0034] 1. The source gNB configures the UE measurement procedure, and the UE reports based on the measurement configuration.

[0035] 2. The source gNB decides to handover the UE based on the Measurement Report and RRM information.

[0036] 3. The source gNB sends a handover request message to the target gNB, passing a transparent RRC container containing the necessary information to prepare the handover on the target side. This information includes at least the target cell ID, KgNB*, the UE's C-RNTI at the source gNB, RRM-configuration including the UE's inactivity time, basic AS-configuration including antenna information and DL carrier frequency, the current QoS flow-to-DRB mapping rule applied to the UE, SIB1 from the source gNB, the UE's capabilities for different RATs, and measurement information reported by the UE, including PDU session-related information and, if available, beam-related information. The PDU session-related information includes slice information and QoS flow-level QoS configuration files. The source gNB may further request a DAPS handover for one or more DRBs.

[0037] Note 1: After the handover request is sent, the source gNB should not reconfigure the UE, including performing mapping of reflected QoS flows to DRBs.

[0038] 4. Admission control may be performed by the target gNB. If slice information is sent to the target gNB, slice-aware admission control should be performed. If a PDU session is associated with an unsupported slice, the target gNB should reject such a PDU session.

[0039] 5. The target gNB prepares the handover with L1 / L2 and sends a HANDOVER REQUEST ACKNOWLEDGE to the source gNB, which contains a transparent container that is sent as an RRC message to the UE to perform the handover, and indicates whether or not the target gNB accepts the DAPS handover.

[0040] Note 2: Once the source gNB receives the HANDOVER REQUEST ACKNOWLEDGE or the transmission of the handover command is initiated in the downlink, data transfer may begin.

[0041] Note 3: For a DRB configured with DAPS, downlink PDCP SDUs use the SN forwarding assigned by the source gNB until the SN assignment is passed to the target gNB in ​​step 8b, and normal data forwarding follows the definition in 9.2.3.2.3.

[0042] 6. The source gNB triggers the Uu handover by sending an RRCReconfiguration message to the UE. The message includes information necessary to access the target cell, i.e., at least the target cell ID, the new C-RNTI, and the selected target gNB security algorithm identifier (security algorithm). It may also include a set of dedicated RACH resources, association of the RACH resources with SSBs, association of the RACH resources with UE-specific CSI-RS configurations, system information of common RACH resources and the target cell, etc.

[0043] Note 4: For a DRB configured with DAPS, the source gNB does not stop transmitting downlink packets until it receives a HANDOVER SUCCESS message from the target gNB in ​​step 8a.

[0044] Note 4a: CHO cannot be configured at the same time as DAPS handover.

[0045] 7a. For a DRB configured with DAPS, the source gNB sends an EARLY STATUS TRANSFER message. The DL COUNT value conveyed in the EARLY STATUS TRANSFER message indicates the PDCP SN and HFN of the first PDCP SDU transferred by the source gNB to the target gNB. The source gNB does not stop assigning SNs to downlink PDCP SDUs until it sends an SN STATUS TRANSFER message to the target gNB in ​​step 8b.

[0046] 7. For DRBs where DAPS is not configured, the source gNB sends an SN STATUS TRANSFER message to the target gNB to convey the uplink PDCP SN receiver state and downlink PDCP SN transmitter state (i.e., in the case of RLC AM) of the DRB to which the PDCP state reservation applies. The uplink PDCP SN receiver state contains at least the PDCP SN of the first lost UL PDCP SDU and may also contain a bitmap of the reception state of out-of-sequence UL PDCP SDUs that the UE needs to retransmit at the target cell (if present). The downlink PDCP SN transmitter state indicates that the target gNB should assign the next PDCP SN for the new PDCP SDU and has not yet assigned it.

[0047] Note 5: In case of DAPS handover, the uplink PDCP SN receiver status and downlink PDCP SN transmitter status of a DRB with RLC-AM and no DAPS configured may be sent in the SN STATUS TRANSFER message in step 8b instead of step 7.

[0048] Note 6: For DAPS configured DRBs, the source gNB may send an additional EARLY STATUS TRANSFER message between step 7 and step 8b to inform the UE that the forwarded PDCP SDUs will be discarded. The target gNB does not send forwarded downlink PDCP SDUs to the UE and discards them if their COUNT is less than the transmitted DL COUNT value and no transmission has yet been attempted.

[0049] 8. The UE synchronizes to the target cell and completes the RRC handover process by sending an RRCReconfigurationComplete message to the target gNB. In the case of a DAPS handover, the UE does not leave the source cell even when it receives the RRCReconfiguration message. The UE releases source resources and configuration and stops DL / UL reception / transmission with the source upon receiving an explicit release from the target node.

[0050] Note 6a: From the RAN perspective, a DAPS handover is considered complete only after the UE has released the source cell following an explicit request from the target node. RRC is suspended and no subsequent handover or inter-RAT handover can be initiated until the source cell has been released.

[0051] In the case of 8a / b.DAP handover, the target gNB sends a HANDOVER SUCCESS message to the source gNB to inform it that the UE has successfully accessed the target cell. In response, the source gNB sends an SN STATUS TRANSFER message for DRBs for which DAPS is configured. The description in step 7 applies to these DRBs, after which normal data transfer takes place as defined in 9.2.3.2.3.

[0052] Note 7: If DAPS is configured, the uplink PDCP SN receiver status and the downlink PDCP SN transmitter status are also conveyed in the SN STATUS TRANSFER message in step 8b for DRB with RLC-UM.

[0053] Note 8: For a DRB configured with DAPS, the source gNB does not stop passing uplink QoS flows to the UPF until it sends the SN STATUS TRANSFER message in step 8b. The target gNB does not forward QoS flows of uplink PDCP SDUs that have been successfully received in order to the UPF until it receives the SN STATUS TRANSFER message. Here, the first missing SN in the UL HFN and uplink PDCP SN receiver state indicates that uplink PDCP SDUs have started to be transmitted to the UPF. The target gNB does not provide uplink PDCP SDUs with a UL COUNT value lower than the provided value.

[0054] Note 9: Invalid.

[0055] 9. The target gNB sends a PATH SWITCH REQUEST message to the AMF to trigger the 5GC to switch the DL data path to the target gNB and establish an NG-C interface instance to the target gNB.

[0056] 10.5GC switches the DL data path to the target gNB. The UPF sends one or more "ending mark" packets on the old path of each PDU session / tunnel to the source gNB, after which any U-plane / TNL resources can be released to the source gNB.

[0057] 11. The AMF acknowledges the PATH SWITCH REQUEST message with a PATH SWITCH REQUEST ACKNOWLEDGE message.

[0058] 12. After receiving the PATH SWITCH REQUEST ACKNOWLEDGE message from the AMF, the target gNB sends a UE CONTEXT RELEASE to inform the source gNB that the switch has been successful. The source gNB can then release the radio and C-plane related resources associated with the UE context. Any ongoing data transfer can continue.

[0059] The above describes the inter-cell mobility, i.e. cell change process, in various scenarios.

[0060] The inventors of the present invention have discovered that when a terminal moves from the coverage area of ​​one cell to the coverage area of ​​another cell, it is necessary to perform a serving cell change at some point. Currently, in various scenarios, the serving cell change is triggered by L3 measurements, performed by RRC signaling, and involves a complete L1 (and L2) reset. Therefore, it results in longer time delays, larger signaling overhead, and longer interruption times than beam switching mobility.

[0061] In view of at least one of the above problems, embodiments of the present invention provide a cell change method and apparatus. [Means for solving the problem]

[0062] A first aspect of an embodiment of the present invention provides a cell change device arranged in a terminal device, the cell change device including: a first transmitter unit that transmits measurement results to a first network node; a first receiver unit that receives L1 signaling and / or L2 signaling from the first network node; and a first change unit that changes from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

[0063] A second aspect of an embodiment of the present invention provides a cell change device, which is applied to a first network node, including: a third receiving unit that receives a measurement result from a terminal device; and a second transmitting unit that transmits the L1 signaling and / or the L2 signaling to the terminal device to instruct the terminal device to change from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

[0064] In a third aspect of the present invention, there is provided a terminal device including the device according to the first aspect of the present invention.

[0065] A fourth aspect of the present invention provides a network node including the apparatus according to the second aspect of the present invention.

[0066] In a fifth aspect of the present invention, there is provided a communication system including a terminal device according to the third aspect of the present invention and / or a network node according to the fourth aspect of the present invention.

[0067] A sixth aspect of an embodiment of the present invention provides a cell change method, which is applied to a terminal device, comprising the steps of: transmitting measurement results to a first network node; receiving L1 signaling and / or L2 signaling from the first network node; and changing from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

[0068] A seventh aspect of an embodiment of the present invention provides a cell change method, applied to a first network node, comprising: receiving measurement results from a terminal device; and transmitting L1 signaling and / or L2 signaling to the terminal device to instruct the terminal device to change from a serving cell to a cell indicated by L2 signaling and / or L1 signaling.

[0069] In an eighth aspect of the present invention, there is provided a computer-readable program that, when executed in a cell change device or a terminal device, causes the cell change device or the terminal device to perform the cell change method described in the sixth aspect of the present invention.

[0070] In a ninth aspect of the present invention, there is provided a storage medium having stored thereon a computer-readable program, which, when executed, causes a cell change device or a terminal device to perform the cell change method described in the sixth aspect of the present invention.

[0071] In a tenth aspect of the present invention, there is provided a computer readable program which, when executed in a cell change device or a network node, causes the cell change device or the network node to perform the cell change method according to the seventh aspect of the present invention.

[0072] In an eleventh aspect of the present invention, there is provided a storage medium having stored thereon a computer readable program, the storage medium causing a cell change device or a network node to perform the cell change method according to the seventh aspect of the present invention when the program is executed.

[0073] One of the advantageous effects of the embodiment of the present invention is as follows: After a terminal device sends a measurement result to a source network node, the terminal device receives L1 signaling and / or L2 signaling from the source network node, and changes from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for implementing an L1 / L2-based cell change procedure, and reducing delay, signaling overhead, and interruption time.

[0074] As shown in the following description and drawings, specific embodiments of the present invention are disclosed in detail to illustrate ways in which the principles of the present invention can be employed. However, the scope of the present invention is not limited to these embodiments. The present invention encompasses all modifications, alterations, and equivalents within the spirit and scope of the appended claims.

[0075] Features described and / or shown in one embodiment may be used in the same or similar manner in one or more other embodiments, may be combined with features in other embodiments, or may be substituted for features in other embodiments.

[0076] It should be noted that in this text, the term "comprise / have" means the presence of a feature, element, step or component, and does not exclude the presence or addition of one or more other features, elements, steps or components. [Brief explanation of the drawings]

[0077] Elements and features depicted in one drawing and one embodiment of an example of the invention may be combined with elements and features shown in one or more drawings or embodiments, and in the drawings, like reference numerals may indicate corresponding elements in multiple drawings and may indicate corresponding elements used in more than one embodiment.

[0078] The drawings included are used to further understand the embodiments of the present invention, constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the written description, explain the principles of the present invention. Note that the drawings described below are merely some examples of the present invention, and those skilled in the art can easily imagine other drawings based on these drawings. [Figure 1] A schematic diagram of an example of a mobility procedure between gNB-DUs within a gNB-CU. [Figure 2] FIG. 10 is a schematic diagram of an example of inter-gNB-CU mobility signaling flow. [Figure 3]FIG. 1 is a schematic diagram of an example of a handover procedure within an AMF / UPF. [Figure 4] 1 is a schematic diagram of an example of a communication system according to an embodiment of the present invention; [Figure 5] FIG. 1 is a schematic diagram of an example deployment scenario of NG-RAN according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic diagram of an example deployment scenario of an IAB according to an embodiment of the present invention. [Figure 7] FIG. 2 is a schematic diagram of an example of a cell change method according to the first embodiment of the present invention. [Figure 8] 1 is a schematic diagram of an example of a basic signaling flow of cell change (cell mobility) based on L1 signaling and / or L2 signaling according to a first embodiment of the present invention; [Figure 9] FIG. 10 is a schematic diagram of an example of a cell change method according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a schematic diagram of an example of a cell change method according to a third embodiment of the present invention. [Figure 11] FIG. 10 is a schematic diagram of an example of a cell changing device according to a fourth embodiment of the present invention. [Figure 12] FIG. 10 is a schematic diagram of an example of a cell change device according to a fifth embodiment of the present invention. [Figure 13] FIG. 10 is a schematic block diagram of an example of a system configuration of a terminal device according to a sixth embodiment of the present invention. [Figure 14] FIG. 13 is a schematic block diagram of an example of a system configuration of a network node according to a seventh embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0079] The above and other features of the present invention will become apparent from the following description. In the specification and drawings, specific embodiments of the present invention are disclosed in detail, and some of the embodiments in which the principles of the present invention can be adopted are shown. However, the present invention is not limited to the described embodiments. The present invention includes all modifications, variations, and equivalents within the scope of the appended claims. Below, various embodiments of the present invention will be described with reference to the drawings. These embodiments are merely illustrative and do not limit the present invention.

[0080] In embodiments of the present invention, the terms "first," "second," etc. are used in titles to distinguish between different elements, but do not represent the spatial arrangement or temporal order of these elements, and these elements are not limited to these terms. The term "and / or" includes any and all combinations of one or more of the terms listed in the associated list. The terms "comprise," "include," "have," etc. refer to the presence of listed features, elements, elements, or components, but do not exclude the presence or addition of one or more other features, elements, elements, or components.

[0081] In the embodiments of the present invention, the singular forms "one," "the," etc., include the plural and should be understood broadly as "one kind" or "one class," and are not limited to "one." Furthermore, the term "said" should be understood to include both the singular and the plural, unless the context clearly indicates otherwise. Furthermore, the term "described in" should be understood to mean "described at least in part," and the term "based on" should be understood to mean "based at least in part," unless the context clearly indicates otherwise.

[0082] In embodiments of the present invention, the terms "communication network" or "wireless communication network" may refer to a network conforming to any communication standard, such as, for example, Long Term Evolution (LTE), Long Term Evolution Advanced (LTE-A, LTE-Advanced), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), etc.

[0083] Additionally, communications between devices in a communications system may occur according to any stage of communications protocol, including, but not limited to, 1G (generation), 2G, 2.5G, 2.75G, 3G, 4G, 4.5G, and 5G, New Radio (NR), and / or other currently known or future developed communications protocols.

[0084] In an embodiment of the present invention, the term "network device" or "network node" refers to a device in a communication system that allows a terminal device to access the communication system and provides a service to the terminal device, for example. The network device or network node may include, but is not limited to, a "node" and / or a "donor" in the IAB architecture, a base station (BS), an access point (AP), a transmission reception point (TRP), a broadcast transmitter, a mobility management entity (MME), a gateway, a server, a radio network controller (RNC), a base station controller (BSC), etc.

[0085] Here, the base station may include, but is not limited to, a Node B (NodeB or NB), an evolved Node B (eNodeB or eNB), and a 5G base station (gNB), as well as a remote radio head (RRH), a remote radio unit (RRU), a relay, or a low-power node (e.g., femto, pico, etc.). The term "base station" may include some or all of these functions, and each base station may provide communication coverage for a specific geographic area. For example, a 5G base station (gNB) may include one gNB CU and one or more gNB DUs, where the CU / DU is a logical node of the gNB that has some of the functions of the gNB. The term "cell" may refer to a base station and / or its coverage area depending on the context in which the term is used. A gNB-DU supports one or more cells, and a cell is supported by only one gNB-DU.

[0086] In the embodiments of the present invention, the term "User Equipment" (UE) or "Terminal Equipment" (TE) refers to a device that accesses a communication network and receives network services via, for example, a network device. The terminal device may be fixed or mobile and may also be referred to as a mobile station (MS), a terminal, a subscriber station (SS), an access terminal (AT), a station, etc., and is, for example, a terminal device served by an IAB node or an IAB donor in the IAB architecture.

[0087] Here, the terminal device may include, but is not limited to, a cellular phone, a personal digital assistant (PDA), a wireless modulation / demodulation device, a wireless communication device, a handheld device, a machine-type communication device, a laptop computer, a cordless phone, a smartphone, a smart watch, a digital camera, etc.

[0088] Furthermore, for example, in a scenario such as the Internet of Things (IoT), the user device may be a monitoring or measurement device or apparatus, including, but not limited to, a Machine Type Communication (MTC) terminal, an in-vehicle communication terminal, an industrial wireless device, a surveillance camera, a Device to Device (D2D) terminal, a Machine to Machine (M2M) terminal, etc.

[0089] In the embodiments of the present invention, "when," "in the case of," "for the case of," and "if," all mean based on one or more conditions or states, etc. Also, these expressions may be interchangeable.

[0090] The following describes example scenarios of the present invention with reference to some examples, but the present invention is not limited thereto.

[0091] 4 is a schematic diagram of an example of a communication system according to an embodiment of the present invention, and will be briefly described using a terminal device and a network device as an example. As shown in FIG. 4, the communication system 100 includes a first network node 101 and a terminal device 102. When the terminal device 102 performs a cell change, the first network node 101 is both a source network node and a target network node. Alternatively, as shown in FIG. 4, the communication system 100 may further include a second network node 103. In this case, when the terminal device 102 performs a cell change, the first network node 101 is the source network node and the second network node 103 is the target network node.

[0092] For simplicity, only one terminal device will be described as an example in FIG.

[0093] In some embodiments, for an inter-gNB cell change, i.e., an inter-gNB-CU cell change, the first network node 101 and the second network node 103 are, for example, NR gNBs.

[0094] For a cell change between gNB-DUs, the first network node 101 and the second network node 103 are different gNB-DUs within the same gNB-CU.

[0095] For a cell change within a gNB-DU, the first network node 101 and the second network node 103 are different TRPs or repeaters within the same gNB-DU, etc. Alternatively, when the first network node 101 is both a source network node and a target network node, and both the source cell and the target cell are in the first network node 101, the communication system 100 according to an embodiment of the present invention includes the first network node 101 and a terminal device 102.

[0096] In some embodiments, FIG. 4 illustrates an IAB network in which terminal device 102 may be a UE or an IAB-MT.

[0097] For a cell change between IAB-donor-CUs, the first network node 101 and the second network node 103 are different IAB-donor-CUs, i.e., when the terminal device 102 needs to perform a cell change, the first network node 101 is the source IAB-donor-CU and the second network node 103 is the target IAB-donor-CU.

[0098] For a cell change between IAB-donor-DUs within an IAB-donor-CU, the first network node 101 and the second network node 103 are different IAB-donor-DUs within the same IAB-donor-CU, i.e., when the terminal device 102 needs to perform a cell change, the first network node 101 is the source IAB-donor-DU and the second network node 103 is the target IAB-donor-DU.

[0099] For a cell change between IAB-nodes, a communication system 100 according to an embodiment of the present invention includes a first network node 101 and a terminal device 102. When the terminal device 102 needs to perform a cell change, the first network node 101 is both a source IAB-donor-DU and a target IAB-donor-DU.

[0100] In an embodiment of the present invention, existing or future services may be performed between the first network node 101 and / or the second network node 103 and the terminal device 102. For example, these services may include, but are not limited to, enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra-Reliable and Low-Latency Communication (URLLC) and associated communications for reduced-capability terminal devices.

[0101] The cell change method according to the embodiment of the present invention can be applied to various deployment scenarios, such as an NG-RAN deployment scenario and an IAB deployment scenario.

[0102] 5 is a schematic diagram of an example of a deployment scenario of an NG-RAN according to an embodiment of the present invention. As shown in FIG. 5, the NG-RAN includes a set of gNBs connected to a 5GC via an NG interface. The gNBs can be interconnected via an Xn interface. One gNB can include one gNB-CU and one or more gNB-DU(s), where one gNB-CU and one gNB-DU are connected via an F1 interface, and one gNB-DU can only be connected to one gNB-CU.

[0103] 6 is a schematic diagram of an example of an IAB deployment scenario according to an embodiment of the present invention. As shown in FIG. 6, the NG-RAN wirelessly connects to a gNB that can provide services to the IAB-nodes via an IAB-node, which is referred to as an IAB-donor for supporting the IAB. The IAB-donor includes one IAB-donor-CU and one or more IAB-donor-DU(s).

[0104] Unless otherwise specified, all functions defined for the gNB-DU apply equally to the IAB-DU and IAB-donor-DU, all functions defined for the gNB-CU apply equally to the IAB-donor-CU, and all functions defined for the UE apply equally to the IAB-MT.

[0105] Various aspects of embodiments of the present invention will now be described with reference to the drawings, which are merely illustrative and not limiting of the present invention.

[0106] Example 1 An embodiment of the present invention provides a cell change method, which is applied to a terminal device, for example, the terminal device 102 in FIG.

[0107] 7 is a schematic diagram of an example of a cell change method according to Example 1 of the present invention. As shown in FIG. 7, the method includes the following steps:

[0108] Step 701: Send a measurement result to a first network node.

[0109] Step 702: Receive L1 signaling and / or L2 signaling from the first network node.

[0110] Step 703: Change from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling.

[0111] This provides an efficient mechanism for implementing an L1 / L2-based cell change procedure by having the terminal device send measurement results to the source network node, then receiving L1 signaling and / or L2 signaling from the source network node, and changing from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling, thereby reducing delay, signaling overhead and interruption time.

[0112] In some embodiments, the cell switch / change includes at least one of a serving cell change, a special cell change, and a primary cell change (switch).

[0113] In some embodiments, the source and target cells in a cell change may be synchronous or asynchronous.

[0114] In some embodiments, the source and target cells in a cell change are either on the same frequency or on different frequencies.

[0115] In some embodiments, the source cell and / or the target cell in a cell change may operate in FR1 or FR2.

[0116] In some embodiments, the first network node is the source network node, ie the network node to which the source cell belongs.

[0117] In some embodiments, L1 refers to Layer 1, which includes, for example, the physical layer.

[0118] In some embodiments, L2 refers to Layer 2, which may include, for example, a MAC layer or sublayer, a PDCP layer or sublayer, and an RLC layer or sublayer.

[0119] In some embodiments, L3 refers to Layer 3, which includes, for example, the RRC layer.

[0120] In step 701, the terminal device transmits measurement results to a first network node, for example, including at least one of reporting the measurement results via RRC signaling, reporting the measurement results via L1 signaling, and reporting the measurement results via MAC CE.

[0121] In some embodiments, reporting the measurements via RRC signaling includes a measurement reporting procedure.

[0122] In some embodiments, reporting measurements via L1 signaling includes reporting SSB and / or CSI-RS measurements via L1 signaling.

[0123] In some embodiments, reporting the measurements via L1 signaling includes reporting the measurements periodically and / or reporting the measurements triggered by an event.

[0124] In some embodiments, reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction.

[0125] In some embodiments, reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, measurement results of the beams, whether or not there are any available beams, and the number of available beams.

[0126] In some embodiments, the MAC CE is different from the BFR MAC CE.

[0127] In some embodiments, the MAC CE is periodically triggered and / or event triggered.

[0128] For example, the events may include the MAC receiving an L1 indication and / or receiving an L3 indication.

[0129] In step 702, the terminal device receives L1 signaling and / or L2 signaling from the first network node, and in step 703, the terminal device changes from the current serving cell to the cell indicated by the L2 signaling and / or L1 signaling.

[0130] For example, the terminal device receives L1 signaling from a first network node and changes its current serving cell to a cell indicated by the L1 signaling.

[0131] Also, for example, the terminal device receives L2 signaling from the first network node and changes the current serving cell to a cell indicated by the L2 signaling.

[0132] Also, for example, a terminal device receives L2 signaling and L1 signaling from a first network node, where the L2 signaling includes a plurality of indicated cells and the L1 signaling indicates one cell among the plurality of cells, and the terminal device changes from a current serving cell to the cell indicated by the L1 signaling.

[0133] In some embodiments, the L1 signaling is downlink control information (DCI).

[0134] In some embodiments, the L2 signaling is MAC CE.

[0135] In some embodiments, the L1 signaling includes: Cell information, TCI state ID, e.g., L1 signaling reuses an existing TCI state ID or indicates / updated DCI based on an existing TCI state ID; TA information, A UE identifier assigned for the terminal device by the target cell, e.g., C-RNTI; HARQ feedback information in L1 signaling, or The scheduling information indicates at least one of the following, including, for example, a UL grant and / or a DL assignment in the target cell.

[0136] In some embodiments, the L2 signaling includes: Cell information, TCI state ID, e.g., L2 signaling reuses an existing TCI state ID or indicates / updated DCI based on an existing TCI state ID; TA information, a UE identifier, e.g., C-RNTI, assigned for the terminal device by the target cell; HARQ feedback information in L2 signaling, or The scheduling information indicates at least one of the following, including, for example, a UL grant and / or a DL assignment in the target cell.

[0137] For example, the terminal device receives L2 signaling and L1 signaling from a first network node and changes its current serving cell to a cell indicated by the L2 signaling and L1 signaling, where the L2 signaling and the L1 signaling indicate different information of the same cell, for example, the L1 signaling indicates the TCI state ID of the cell and the L2 signaling indicates the TA information of the cell.

[0138] In some embodiments, the step of changing from the serving cell to a cell indicated by L2 signaling and / or L1 signaling comprises: starting a first timer T1 for controlling a cell change procedure based on L1 signaling and / or L2 signaling; applying the indicated cell configuration; initiating a random access procedure to the indicated cell; considering the C-RNTI associated with the indicated cell as its own C-RNTI; receiving DL transmissions in the cell based on the indicated scheduling information; or Sending information to the indicated cell or a network node to which the cell belongs, the network node to which the cell belongs including at least one of being the second network node or the first network node.

[0139] In some embodiments, this C-RNTI may have been previously configured by RRC signaling (e.g., when the terminal device receives configuration information of a set of cells from a first network node, and this RRC signaling configuration refers to the corresponding configuration of cells indicated by L1 and / or L2 signaling in the configuration information), or this C-RNTI may be included in the L1 / L2 signaling.

[0140] If indicated by only one signaling, this C-RNTI is applied; if indicated by multiple signaling, the most recent one is applied, or the order of L1, L2, L3 is applied.

[0141] In some embodiments, if the terminal device applies the configuration of the indicated cell, the terminal device considers the cell change to be complete or the change to the indicated cell to be successful.

[0142] In some embodiments, applying the indicated cell configuration includes applying at least one of the cell's SSB frequency, TA value, and physical layer configuration.

[0143] In some embodiments, the terminal device receives configuration information of a group of cells from the first network node, the configuration information representing a configuration corresponding to the cells indicated by the L2 signaling and / or the L1 signaling.

[0144] In some embodiments, if the terminal device completes the random access procedure, the terminal device considers the cell change to be complete or the change to the indicated cell to be successful.

[0145] In some embodiments, the cell change is considered to be complete or the change to the indicated cell is successful when the terminal device receives the first DL transmission in the indicated cell, for example, if the first DL transmission is successfully received.

[0146] In some embodiments, the indicated cell is a target cell and the second network node is a target network node.

[0147] In some embodiments, the information sent by the terminal device to the cell, the second network node or the first network node indicates that the cell change has been completed or that the change to the indicated cell has been successful.

[0148] In some embodiments, sending the information to the indicated cell or the network node to which the cell belongs comprises at least one of conveying the information in an RRC reconfiguration complete message, indicating the information by L1 signaling and / or L2 signaling feedback, the feedback being generated based on feedback information indicated by L2 signaling and / or L1 signaling, or indicating the information by scheduling information indicated by L1 signaling and / or L2 signaling.

[0149] In some embodiments, as shown in FIG. 7, the method further includes the following steps:

[0150] Step 704: After the cell change is completed or the change to the indicated cell is successful, the terminal device starts communication with the indicated cell and / or stops the first timer T1.

[0151] For example, the terminal device initiating communication with the indicated cell may include the terminal device transmitting and receiving dedicated channels and / or signals, and / or the terminal device transmitting and receiving non-dedicated channels and / or signals, e.g., broadcast channels, paging channels.

[0152] In some embodiments, as shown in FIG. 7, the method further includes the following steps:

[0153] Step 705: If the change to the indicated cell fails, the terminal device initiates a connection re-establishment process.

[0154] For example, the first timer has timed out, A random access procedure initiated by the terminal device to the indicated cell fails or the number of failures reaches a predetermined number; and If at least one of the following occurs: the terminal device is unable to apply the configuration or part of the configuration of the indicated cell, the change to the indicated cell is considered to have failed.

[0155] In some embodiments, as shown in FIG. 7, the method further includes the following steps:

[0156] Step 706: Receive configuration information of a group of cells from a first network node, where the group of cells are candidate cells for performing a cell change procedure based on L1 signaling and / or L2 signaling.

[0157] In some embodiments, the first network node implicitly indicates that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling, for example, if the terminal device receives configuration information of a group of cells, the terminal device assumes that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling.

[0158] In some embodiments, the first network node explicitly indicates that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling, e.g. via a broadcast message and / or an RRC dedicated message.

[0159] In some embodiments, as shown in FIG. 7, the method further includes the following steps:

[0160] Step 707: Receive broadcast information and / or an RRC dedicated message including first indication information from a first network node.

[0161] In some embodiments, the first instruction comprises: the first network node or the cell sending the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information only supports a cell change procedure based on L3 signaling, or Indicate that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling and a cell change procedure based on L3 signaling.

[0162] In some embodiments, as shown in FIG. 7, the method further includes the following steps:

[0163] Step 708: Receive an RRC reconfiguration message from the first network node.

[0164] Step 709: Perform a cell change based on the RRC reconfiguration message.

[0165] In some embodiments, steps 704-709 are optional steps.

[0166] In some embodiments, if a cell change procedure based on L1 / L2 signaling is used, steps 702 and 703 are performed, and if a cell change procedure based on RRC signaling is used, steps 708 and 709 are performed.

[0167] In some embodiments, the terminal device further receives configuration information for the group of cells from the first network node, as described in step 706 .

[0168] 8 is a schematic diagram of an example of a basic signaling flow of cell change (cell mobility) based on L1 signaling and / or L2 signaling according to embodiment 1 of the present invention. As shown in FIG. 8, the basic signaling flow includes the following steps: A first network node sends configuration information of a group of cells to a terminal device, i.e., configures multiple candidate cells; The terminal device performs measurements and sends a measurement report to the first network node; The first network node decides on cell change, generates CU-DU interface signaling, performs dynamic switch via L1 / L2 signaling, and may also perform TA (Time Correction) management.

[0169] The following provides an exemplary description of a cell change method according to an embodiment of the present invention with reference to a specific scenario.

[0170] In the case of a cell change within a DU, for example, when the source cell and the target cell are two cells in the same gNB-DU (e.g., a first network node. In an embodiment of the present invention, for a cell change within a DU, the first network node may be referred to as a first network unit), the gNB-DU is connected to the gNB-CU via an F1 interface. Data of the terminal device is transmitted between the gNB-CU and the gNB-DU via a tunnel and is identified by an UL / DL GTP TEID. When performing an inter-cell handover within a gNB-DU, the gNB-CU provides a new UL GTP TEID for the gNB-DU, and the gNB-DU provides a new DL GTP TEID for the gNB-CU.

[0171] In some embodiments, when performing an intra-gNB-DU inter-cell handover based on L1 / L2 signaling, the gNB-CU and gNB-DU interact with each other for new UL / DL GTP TEIDs. This interaction may occur before the gNB-DU provides configuration information of a group of cells for the terminal device, after the gNB-DU receives measurement results (after deciding to change cells), or after the gNB-DU receives feedback from the terminal (success or forward).

[0172] In some embodiments, the time to start using the new UL / DL GTP TEID is upon successful completion of a cell change, a physical layer reconfiguration or reset or partial reset, a MAC reconfiguration or reset or partial reset, an RLC reconfiguration or reconfiguration or partial reestablishment, a PDCP reconfiguration or reconfiguration or partial reestablishment, a PDCP data recovery, or upon receiving an indication (from the terminal or the core network) indicating the use of a new UL / DL GTP TEID.

[0173] In some embodiments, prior to this, the previous UL / DL GTP TEID is used.

[0174] In some embodiments, for a cell change between DUs within a gNB-CU, for example, the source cell is in gNB-DU1 (e.g., a first network node or a source network node or a first network unit), the target cell is in gNB-DU2 (e.g., a second network node or a target network node or a second network unit), and both gNB-DU1 and gNB-DU2 are connected to the gNB-CU via F1.

[0175] In some embodiments, the configuration information of the group of cells configured for the terminal by the network (gNB-DU1) comes from the DU in which the group of cells is located or from the CU connected to DU1. This process may be one in which the source gNB-DU requests the DU in which these cells are located, or one in which the source gNB-DU instructs the connected CU and the CU requests the DU in which these cells are located.

[0176] In some embodiments, before transmitting L1 / L2 signaling to instruct the UE to change cells, the source gNB-DU may request a cell change based on the L1 / L2 signaling from the target gNB-DU via the gNB-CU. For example, the source gNB-DU may send a UL RRC MESSAGE TRANSFER message to the gNB-CU, which carries measurement results (including L1 / L2 / L3 measurement results) and / or an indication indicating a cell change based on the L1 / L2 signaling. The gNB-CU then sends a UE CONTEXT SETUP REQUEST message to the target gNB-DU, carrying all or part of the content included in the UL RRC MESSAGE TRANSFER message. The target gNB-DU responds with a UE CONTEXT SETUP RESPONSE message that includes the indication indicating a cell change based on the L1 / L2 signaling and information indicated by the L1 / L2 signaling (e.g., see the information in the L1 / L2 signaling described above).

[0177] In some embodiments, after the terminal device sends feedback (forward or success) to the target gNB-DU, the gNB-DU sends an F1 message carrying this feedback to the gNB-CU, for example, using a UL RRC MESSAGE TRANSFER message, or using a new message such as a UL MOBILITY FEEDBACK message. After receiving this message, the gNB-CU sends a message to the source gNB-DU to release the context of the terminal device, for example, the message is a UE CONTEXT RELEASE COMMAND.

[0178] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0179] <Example 2> An embodiment of the present invention provides a cell change method, which corresponds to the cell change method applied to the terminal device described in embodiment 1, and reference may be made to the description in embodiment 1 for similar or corresponding content.

[0180] The method is applied to a first network node, for example the first network node 101 in FIG.

[0181] 9 is a schematic diagram of an example of a cell change method according to Example 2 of the present invention. As shown in FIG. 9, the method includes the following steps:

[0182] Step 901: Receive measurement results from the terminal device.

[0183] Step 902: Send L1 signaling and / or L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or L1 signaling.

[0184] In some embodiments, the measurement results are reported via at least one of RRC signaling, L1 signaling, and MAC CE.

[0185] In some embodiments, reporting the measurements via RRC signaling includes a measurement reporting procedure.

[0186] In some embodiments, reporting measurements via L1 signaling includes reporting SSB and / or CSI-RS measurements via L1 signaling.

[0187] In some embodiments, reporting the measurements via L1 signaling includes reporting the measurements periodically and / or reporting the measurements triggered by an event.

[0188] In some embodiments, reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction.

[0189] In some embodiments, reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, measurement results of the beams, whether or not there are any available beams, and the number of available beams.

[0190] In some embodiments, the MAC CE is different from the BFR MAC CE.

[0191] In some embodiments, the MAC CE is periodically triggered and / or event triggered.

[0192] In some embodiments, the event includes an L1 indication and / or an L3 indication.

[0193] In some embodiments, the L1 signaling is DCI and / or the L2 signaling is MAC CE.

[0194] In some embodiments, the L1 signaling includes: Cell information, TCI state ID, TA information, A UE identifier assigned for the terminal device by the target cell, e.g., C-RNTI; HARQ feedback information in L1 signaling, or The scheduling information indicates at least one of the following, including, for example, a UL grant and / or a DL assignment in the target cell.

[0195] In some embodiments, the L2 signaling includes: Cell information, TCI state ID, TA information, A UE identifier assigned for the terminal device by the target cell, e.g., C-RNTI; HARQ feedback information in L2 signaling, or The scheduling information indicates at least one of the following, including, for example, a UL grant and / or a DL assignment in the target cell.

[0196] In some embodiments, as shown in FIG. 9, the method further includes the following steps:

[0197] Step 903: The first network node decides to use a cell change procedure based on L1 signaling and / or L2 signaling, or a cell change procedure based on RRC signaling.

[0198] In some embodiments, the cell change procedure based on L1 signaling and / or L2 signaling includes the first network node sending L1 signaling and / or L2 signaling to the terminal device to trigger a change of serving cell.

[0199] For example, if in step 903 the first network node decides to use a cell change procedure based on L1 signaling and / or L2 signaling, then step 902 is performed.

[0200] In some embodiments, the cell change procedure based on RRC signaling includes the first network node sending an RRC reconfiguration message to the terminal device to trigger a change of serving cell.

[0201] For example, if in step 903 the first network node decides to use the cell change procedure based on RRC signaling, it performs step 906, which will be described below.

[0202] In some embodiments, as shown in FIG. 9, the method further includes the following steps:

[0203] Step 904: Send configuration information of the group of cells to the terminal device.

[0204] In some embodiments, as shown in FIG. 9, the method further includes the following steps:

[0205] Step 905: Providing broadcast information and / or an RRC dedicated message including first indication information to the terminal device.

[0206] The first instruction information is the first network node or the cell sending the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information only supports a cell change procedure based on L3 signaling, or Indicate that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling and a cell change procedure based on L3 signaling.

[0207] Here, the cell change procedure based on L3 signaling is, for example, a cell change procedure based on RRC signaling.

[0208] In some embodiments, the cell change procedure based on RRC signaling includes the first network node sending an RRC reconfiguration message to the terminal device to trigger a change of serving cell.

[0209] In some embodiments, as shown in FIG. 9, the method includes the following steps.

[0210] Step 906: Send an RRC reconfiguration message to the terminal device to trigger a change of the serving cell.

[0211] In other words, if in step 903 the first network node decides to use the cell change procedure based on RRC signaling, then it performs step 906 .

[0212] In some embodiments, steps 903, 904, 905, and 906 are optional steps, and the order in which steps 904 and 905 are performed does not limit the order in which steps 903, 904, 905, and 906 are performed.

[0213] In some embodiments, step 905 may send the indication via broadcast information and / or RRC dedicated messages.

[0214] In some embodiments, the RRC dedicated message explicitly or implicitly indicates support for a cell change procedure based on L1 signaling and / or L2 signaling.

[0215] In some embodiments, the RRC dedicated message implicitly indicating support for a cell change procedure based on L1 signaling and / or L2 signaling comprises the terminal device assuming that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling when sending configuration information of a group of cells to the terminal device.

[0216] In other words, the first network node sending the configuration information of the group of cells to the terminal device is equivalent to implicitly indicating support for the cell change procedure based on L1 signaling and / or L2 signaling via an RRC dedicated message, i.e., steps 904 and 905 are the same step.

[0217] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0218] Example 3 An embodiment of the present invention provides a cell change method, which is applied to a terminal device and a first network node, and corresponds to the cell change method applied to the terminal device described in embodiment 1 and the cell change method applied to the first network node described in embodiment 2, and duplicated descriptions of similar contents will be omitted.

[0219] 10 is a schematic diagram of an example of a cell change method according to a third embodiment of the present invention, the method being applied to a terminal device and a first network node. As shown in FIG. 10, the method includes the following steps:

[0220] Step 1001: The terminal device sends a measurement result to a first network node.

[0221] Step 1002: The first network node sends L1 signaling and / or L2 signaling to the terminal device.

[0222] Step 1003: The terminal device changes from the serving cell to a cell indicated by L2 signaling and / or L1 signaling.

[0223] In some embodiments, as shown in FIG. 10, the method may further include the following steps:

[0224] Step 1004: The first network node sends configuration information of the group of cells to the terminal device.

[0225] Step 1005: The terminal device performs measurements.

[0226] Step 1006: The first network node decides to perform a cell change based on L1 signaling and / or L2 signaling.

[0227] Step 1007: The first network node generates L1 signaling and / or L2 signaling.

[0228] The above steps 1004, 1005, 1006 and 1007 are optional steps.

[0229] In the embodiment of the present invention, the specific implementation of steps 1001 to 1007 may refer to the descriptions in the first and second embodiments, and redundant descriptions will be omitted here.

[0230] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0231] Example 4 An embodiment of the present invention provides a cell change device, which is applied to a terminal device. The solution principle of the device is the same as that of the method of the first embodiment, so that the specific implementation of the device may refer to the implementation of the method described in the first embodiment, and the same or related content will not be described again.

[0232] 11 is a schematic diagram of an example of a cell changing device according to Example 4 of the present invention. As shown in FIG. 11, a cell changing device 1100 includes the following components.

[0233] The first transmitting unit 1101 transmits the measurement result to the first network node.

[0234] The first receiving unit 1102 receives L1 signaling and / or L2 signaling from a first network node.

[0235] The first changing unit 1103 changes the serving cell to a cell indicated by L2 signaling and / or L1 signaling.

[0236] In some embodiments, the first transmitter 1101 reports the measurement result via at least one of RRC signaling, L1 signaling, and MAC CE.

[0237] In some embodiments, reporting the measurements via RRC signaling includes a measurement reporting procedure.

[0238] In some embodiments, reporting measurements via L1 signaling includes reporting SSB and / or CSI-RS measurements via L1 signaling.

[0239] In some embodiments, reporting the measurements via L1 signaling includes reporting the measurements periodically and / or reporting the measurements triggered by an event.

[0240] In some embodiments, reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction.

[0241] In some embodiments, reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, measurement results of the beams, whether or not there are any available beams, and the number of available beams.

[0242] In some embodiments, the MAC CE is different from the BFR MAC CE.

[0243] In some embodiments, the MAC CE is periodically triggered and / or event triggered.

[0244] In some embodiments, the event includes an L1 indication and / or an L3 indication.

[0245] In some embodiments, the L1 signaling is DCI and / or the L2 signaling is MAC CE.

[0246] In some embodiments, the L1 signaling includes: Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information in L1 signaling, or Indicate at least one of the scheduling information.

[0247] In some embodiments, the L2 signaling includes: Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information in L2 signaling, or Indicate at least one of the scheduling information.

[0248] In some embodiments, the first modifying unit 1103 is starting a first timer for controlling a cell change procedure based on L1 signaling and / or L2 signaling; applying the indicated cell configuration; initiating a random access procedure to the indicated cell; considering the C-RNTI associated with the indicated cell as its own C-RNTI; receiving DL transmissions in the cell based on the indicated scheduling information; or transmitting information to the indicated cell or to the network node to which the cell belongs.

[0249] In some embodiments, if the terminal device receives the first DL transmission on the indicated cell, the terminal device considers the cell change to be complete or has successfully changed to the indicated cell.

[0250] In some embodiments, if the terminal device applies the configuration of the indicated cell, the terminal device considers the cell change to be complete or the change to the indicated cell to be successful.

[0251] In some embodiments, applying the indicated cell configuration includes applying at least one of the cell's SSB frequency, TA value, and physical layer configuration.

[0252] In some embodiments, if the terminal device completes the random access procedure, the terminal device considers the cell change to be complete or the change to the indicated cell to be successful.

[0253] In some embodiments, information sent by the terminal device to the cell or to the network node to which the cell belongs indicates that the cell change is complete or indicates that the change to the indicated cell has been successful.

[0254] In some embodiments, transmitting the information to the indicated cell or to the network node to which the cell belongs comprises: conveying the information in an RRC reconfiguration complete message; Indicating information by L1 signaling and / or feedback of said L2 signaling, or The method includes at least one of indicating the information by scheduling information indicated by L1 signaling and / or L2 signaling.

[0255] In some embodiments, after the cell change is completed or the change to the indicated cell is successful, the terminal device starts communication with the indicated cell and / or stops the first timer.

[0256] In some embodiments, the terminal device initiating communication with the indicated cell includes the terminal device transmitting and receiving dedicated channels and / or signals, and / or the terminal device transmitting and receiving non-dedicated channels and / or signals.

[0257] In some embodiments, if the change to the indicated cell fails, the terminal device initiates a connection re-establishment process.

[0258] In some embodiments, the first timer has timed out; A random access procedure initiated by a terminal device to the indicated cell fails or the number of failures reaches a predetermined number; and If at least one of the following occurs: the terminal device is unable to apply the configuration or part of the configuration of the indicated cell, the change to the indicated cell is deemed to have failed.

[0259] In some embodiments, the apparatus further comprises the following components:

[0260] The second receiving unit 1104 receives configuration information of the group of cells from the first network node.

[0261] In some embodiments, if the terminal device receives configuration information of a group of cells, the terminal device assumes that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling.

[0262] In some embodiments, the apparatus further comprises the following components:

[0263] The third receiving unit 1105 receives broadcast information and / or an RRC dedicated message including the first indication information from the first network node.

[0264] In some embodiments, the first instruction comprises: the first network node or the cell sending the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information only supports a cell change procedure based on L3 signaling, or Indicate that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling and a cell change procedure based on L3 signaling.

[0265] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0266] <Example 5> An embodiment of the present invention provides a cell change device, which is applied to a first network node. The solution principle of the device is the same as that of the method of embodiment 2, so that the specific implementation of the device may refer to the implementation of the method described in embodiment 2, and redundant descriptions of similar or related content will be omitted.

[0267] 12 is a schematic diagram of an example of a cell changing device according to Example 5 of the present invention. As shown in FIG. 12, a cell changing device 1200 includes the following components.

[0268] The fourth receiving unit 1201 receives the measurement result from the terminal device.

[0269] The second transmitting unit 1202 transmits L1 signaling and / or L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or L1 signaling.

[0270] In some embodiments, the measurement results are reported via at least one of RRC signaling, L1 signaling, and MAC CE.

[0271] In some embodiments, reporting the measurements via RRC signaling includes a measurement reporting procedure.

[0272] In some embodiments, reporting measurements via L1 signaling includes reporting SSB and / or CSI-RS measurements via L1 signaling.

[0273] In some embodiments, reporting the measurements via L1 signaling includes reporting the measurements periodically and / or reporting the measurements triggered by an event.

[0274] In some embodiments, reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction.

[0275] In some embodiments, reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, measurement results of the beams, whether or not there are any available beams, and the number of available beams.

[0276] In some embodiments, the MAC CE is different from the BFR MAC CE.

[0277] In some embodiments, the MAC CE is periodically triggered and / or event triggered.

[0278] In some embodiments, the event includes an L1 indication and / or an L3 indication.

[0279] In some embodiments, the L1 signaling is DCI and / or the L2 signaling is MAC CE.

[0280] In some embodiments, the L1 signaling includes: Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information in L1 signaling, or Indicate at least one of the scheduling information.

[0281] In some embodiments, the L2 signaling includes: Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information in L2 signaling, or Indicate at least one of the scheduling information.

[0282] In some embodiments, the apparatus further comprises the following components:

[0283] The determining unit 1203 determines to use a cell change procedure based on L1 signaling and / or L2 signaling, or a cell change procedure based on RRC signaling.

[0284] In some embodiments, the cell change procedure based on L1 signaling and / or L2 signaling comprises the first network node sending L1 signaling and / or L2 signaling to the terminal device to trigger a change of serving cell, and / or the cell change procedure based on RRC signaling comprises the first network node sending an RRC reconfiguration message to the terminal device to trigger a change of serving cell.

[0285] In some embodiments, the apparatus further comprises the following components:

[0286] The third transmitting unit 1204 transmits configuration information of the cell group to the terminal device.

[0287] In some embodiments, the apparatus further comprises the following components:

[0288] The first providing unit 1205 provides the terminal device with broadcast information and / or an RRC dedicated message including the first indication information.

[0289] In some embodiments, the first instruction comprises: the first network node or the cell sending the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell sending the first indication information only supports a cell change procedure based on L3 signaling, or Indicate that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling and a cell change procedure based on L3 signaling.

[0290] In some embodiments, the RRC dedicated message explicitly or implicitly indicates support for a cell change procedure based on L1 signaling and / or L2 signaling.

[0291] In some embodiments, the RRC dedicated message implicitly indicating support for a cell change procedure based on L1 signaling and / or L2 signaling comprises the terminal device assuming that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling if configuration information for a group of cells is sent to the terminal device.

[0292] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0293] Example 6 An embodiment of the present invention further provides a terminal device, which includes the cell change device described in the fourth embodiment.

[0294] 13 is a schematic block diagram of an example of a system configuration of a terminal device according to a sixth embodiment of the present invention. As shown in FIG. 13, the terminal device 1300 may include a processor 1310 and a memory 1320. The memory 1320 stores data and programs and is connected to the processor 1310. Note that this diagram is merely an example, and other types of structures may be used to supplement or replace this structure to realize communication functions or other functions.

[0295] In some embodiments, the functionality of the cell changer may be integrated into processor 1310 .

[0296] In some embodiments, the processor 1310 may be configured to perform the steps of: sending the measurement results to the first network node; receiving L1 signaling and / or L2 signaling from the first network node; and changing from the serving cell to a cell indicated by the L2 signaling and / or L1 signaling.

[0297] In some other embodiments, the cell change device may be configured separately from the processor 1310. For example, the cell change device may be configured as a chip connected to the processor 1310, and the functions of the cell change device are realized under the control of the processor 1310.

[0298] 13, the terminal device 1300 may further include a communication module 1330, an input unit 1340, a display 1350, a power supply 1360, and the like. Here, the functions of the above units are similar to those of the prior art, and therefore, description thereof will be omitted here. Note that the terminal device 1300 does not need to include all of the units shown in FIG. 13. The terminal device 1300 may further include units not shown in FIG. 13, and prior art may be referred to.

[0299] 13, the processor 1310, also referred to as a controller or an operation control device, may include a microprocessor or other processor and / or logic device. The processor 1310 receives inputs and controls the operation of each component of the terminal device 1300.

[0300] Here, the memory 1320 may be, for example, one or more of a buffer, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory, or other suitable devices. Here, various data can be stored, and further, programs for executing information can be stored. Here, the processor 1310 can execute programs stored in the memory 1320 to enable the storage or processing of information, etc. Although not described here, the functions of the other components are similar to existing ones. Here, the components of the terminal device 1300 can be implemented by dedicated hardware, firmware, software, or a combination thereof without departing from the scope of the present invention.

[0301] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0302] Example 7 An embodiment of the present invention further provides a network node, which includes the cell changing device described in embodiment 5.

[0303] Fig. 14 is a schematic block diagram of an example of a system configuration of a network node according to a seventh embodiment of the present invention. As shown in Fig. 14, a network node 1400 may include a processor 1410 (e.g., a central processing unit (CPU)) and a memory 1420, and the memory 1420 is connected to the processor 1410. The memory 1420 may store various data, and may further store an information processing program 1430, execute the program 1430 under the control of the processor 1410, receive various pieces of information transmitted from a terminal device, and transmit various pieces of information to the terminal device.

[0304] In some embodiments, the functionality of the cell changer may be integrated into processor 1410 .

[0305] In some embodiments, the processor 1410 may be configured to perform the steps of receiving measurement results from a terminal device and sending L1 signaling and / or L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or L1 signaling.

[0306] In some other embodiments, the cell change device may be configured separately from the processor 1410. For example, the cell change device may be configured as a chip connected to the processor 1410, and the functions of the cell change device are realized under the control of the processor 1410.

[0307] 14, the network node 1400 may further include a transceiver 1440 and an antenna 1450. The functions of the above components are similar to those of the prior art, and the description thereof will be omitted here. It should be noted that the network node 1400 does not need to include all the units shown in FIG. 14. The network node 1400 may further include units not shown in FIG. 14, and the prior art may be referred to.

[0308] According to this embodiment, after the terminal device transmits the measurement result to the source network node, it receives L1 signaling and / or L2 signaling from the source network node and changes from the serving cell to the cell indicated by the L2 signaling and / or the L1 signaling, thereby providing an efficient mechanism for realizing the L1 / L2-based cell change procedure, and reducing delay, signaling overhead and interruption time.

[0309] Example 8 An embodiment of the present invention further provides a communication system, which includes the terminal device described in embodiment 6 and / or the network node described in embodiment 7. For specific details, refer to the descriptions in embodiment 16 and embodiment 17.

[0310] For example, the configuration of the communication system may refer to Fig. 4. As shown in Fig. 4, the communication system 100 includes a first network node 101 and a terminal device 102. The terminal device 102 may be the same as the terminal device described in the sixth embodiment, and / or the first network node 101 may be the same as the network node described in the seventh embodiment, and redundant descriptions will be omitted.

[0311] The above-described apparatus and method of the present invention may be realized by hardware or a combination of hardware and software. The present invention relates to a computer-readable program that, when executed by a logic unit, causes the logic unit to implement the above-described apparatus or components, or to implement the above-described various methods or steps. The present invention also relates to a storage medium for storing the above-described program, such as a hard disk, magnetic disk, optical disk, DVD, flash memory, etc.

[0312] Each processing method in each device described with reference to the embodiments of the present invention may be implemented by hardware, software modules executed by a processor, or a combination of both. For example, one or more of the functional block diagrams shown in FIG. 11 or one or more combinations of functional block diagrams may correspond to each software module in the flow of a computer program or each hardware module. These software modules may correspond to each step shown in FIG. 7. These hardware modules may be realized by implementing these software modules in hardware using, for example, a field programmable gate array (FPGA).

[0313] The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile hard disk, a CD-ROM, or any other form of storage medium known to those skilled in the art. The storage medium may be connected to the processor so that the processor reads information from the storage medium or writes information to the storage medium, or the storage medium may be a component of the processor. The processor and the storage medium may be located in an ASIC. The software module may be stored in the memory of the mobile terminal or may be stored in a memory card inserted into the mobile terminal. For example, when a device (such as a mobile terminal) uses a relatively large-capacity MEGA-SIM card or a large-capacity flash memory device, the software module may be stored in the MEGA-SIM card or the large-capacity flash memory device.

[0314] One or more functional blocks and / or one or more combinations of functional blocks in the functional block diagram described in FIG. 11 may be implemented by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, or any suitable combination thereof for performing the functions described in this application. One or more functional blocks and / or one or more combinations of functional blocks in the functional block diagram described in FIG. 11 may be implemented, for example, by a combination of computing devices, such as a combination of a DSP and a microprocessor, a combination of multiple microprocessors, one or more microprocessors combined with DSP communication, or any other configuration.

[0315] Although the present invention has been described above with reference to specific embodiments, the above description is merely illustrative and does not limit the scope of protection of the present invention. Various modifications and changes may be made to the present invention without departing from the spirit and principles of the present invention, and these modifications and changes are also within the scope of the present invention.

[0316] Furthermore, the following supplementary notes are disclosed regarding the embodiments including the above examples. (Appendix 1) (Appendix 1) A cell change device disposed in a terminal device, a first transmitter for transmitting the measurement result to a first network node; a first receiver for receiving L1 signaling and / or L2 signaling from the first network node; a first change unit that changes from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling. (Appendix 2) 2. The apparatus of claim 1, wherein the first transmitter reports the measurement results via at least one of RRC signaling, L1 signaling, and MAC CE. (Appendix 3) 3. The apparatus of claim 2, wherein reporting the measurement results via RRC signaling includes a measurement reporting procedure. (Appendix 4) 3. The apparatus of claim 2, wherein reporting the measurement results via L1 signaling includes reporting SSB and / or CSI-RS measurement results via L1 signaling. (Appendix 5) 5. The apparatus of claim 2 or 4, wherein reporting the measurement results via L1 signaling comprises reporting the measurement results periodically and / or reporting the measurement results triggered by an event. (Appendix 6) 3. The apparatus of claim 2, wherein reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam failure. (Appendix 7) 3. The apparatus of claim 2, wherein reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, beam measurement results, whether or not there are available beams, and the number of available beams. (Appendix 8) 8. The apparatus of claim 2 or 7, wherein the MAC CE is different from a BFR MAC CE. (Appendix 9) 9. The apparatus of claim 2, 7, or 8, wherein the MAC CE is periodically triggered and / or event triggered. (Appendix 10) 10. The apparatus of claim 9, wherein the event includes an L1 instruction and / or an L3 instruction. (Appendix 11) The apparatus of claim 1, wherein the L1 signaling is DCI and / or the L2 signaling is MAC CE. (Appendix 12) The L1 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling, or 12. The apparatus of claim 1 or 11, wherein the apparatus indicates at least one of the scheduling information. (Appendix 13) The L2 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L2 signaling, or 12. The apparatus of claim 1 or 11, wherein the apparatus indicates at least one of the scheduling information. (Appendix 14) The first change unit is starting a first timer for controlling a cell change procedure based on the L1 signaling and / or the L2 signaling; applying the indicated configuration of the cell; initiating a random access procedure to the indicated cell; considering the C-RNTI associated with the indicated cell as its own C-RNTI; receiving DL transmission in the cell based on the indicated scheduling information; or 2. The apparatus of claim 1, further comprising: transmitting information to the indicated cell or a network node to which the cell belongs. (Appendix 14a) The device described in Supplementary Note 14, wherein if the terminal device receives the first DL transmission in the indicated cell, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 15) The device described in Supplementary Note 14, wherein if the terminal device applies the configuration of the indicated cell, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 16) Applying the indicated cell configuration 16. The apparatus of claim 14 or 15, comprising applying at least one of an SSB frequency, a TA value, and a physical layer configuration of the cell. (Appendix 17) The device described in Supplementary Note 14, wherein if the terminal device completes the random access procedure, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 18) The apparatus of claim 14, wherein the information transmitted by the terminal device to the cell or the network node to which the cell belongs indicates that a cell change has been completed or that a change to the indicated cell has been successful. (Appendix 19) transmitting information to the indicated cell or a network node to which the cell belongs, conveying said information in an RRC reconfiguration complete message; Indicating said information by feedback of said L1 signaling and / or said L2 signaling, or 19. The apparatus of claim 14 or 18, further comprising at least one of indicating the information using scheduling information indicated by the L1 signaling and / or the L2 signaling. (Appendix 20) An apparatus described in any of Supplementary Notes 1, 14 to 19, wherein after the cell change is completed or the change to the indicated cell is successful, the terminal device starts communication with the indicated cell and / or stops the first timer. (Appendix 21) The apparatus of claim 20, wherein the terminal device initiating communication with the indicated cell includes transmitting and receiving a dedicated channel and / or signal of the terminal device, and / or transmitting and receiving a non-dedicated channel and / or signal of the terminal device. (Appendix 22) The apparatus of claim 1 or 14, wherein if the change to the indicated cell fails, the terminal device initiates a connection re-establishment process. (Appendix 23) that the first timer has timed out; A random access procedure initiated by the terminal device to the indicated cell fails or the number of failures reaches a predetermined number; and The apparatus of claim 22, wherein the change to the indicated cell is considered to have failed if at least one of the following occurs: the terminal device is unable to apply the indicated configuration or part of the configuration of the cell. (Appendix 24) 24. The apparatus of any of Supplementary Notes 1 to 23, further comprising: a second receiving unit configured to receive configuration information of a group of cells from the first network node. (Appendix 25) 25. The apparatus of claim 1 or 24, wherein if the terminal device receives configuration information of a group of cells, the terminal device assumes that the first network node supports a cell change procedure based on the L1 signaling and / or the L2 signaling. (Appendix 26) 26. The apparatus of claim 1, 24, or 25, further comprising: a third receiver configured to receive broadcast information and / or an RRC dedicated message including the first indication information from the first network node. (Appendix 27) The first instruction information is the first network node or the cell transmitting the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; The first network node or the cell transmitting the first indication information only supports a cell change procedure based on L3 signaling, or 27. The apparatus of claim 26, wherein the first network node or the cell transmitting the first indication information indicates that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling, and a cell change procedure based on L3 signaling. (Appendix 28) A cell change device, applied in a first network node, comprising: a fourth receiving unit that receives the measurement result from the terminal device; and a second transmitting unit that transmits the L1 signaling and / or the L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling. (Appendix 29) 29. The apparatus of claim 28, wherein the measurement results are reported via at least one of RRC signaling, L1 signaling, and MAC CE. (Appendix 30) 30. The apparatus of claim 29, wherein reporting measurement results via RRC signaling includes a measurement reporting procedure. (Appendix 31) 30. The apparatus of claim 29, wherein reporting the measurement results via L1 signaling includes reporting SSB and / or CSI-RS measurements via L1 signaling. (Appendix 32) 32. The apparatus of claim 29 or 31, wherein reporting the measurement results via L1 signaling comprises reporting the measurement results periodically and / or reporting the measurement results triggered by an event. (Appendix 33) 30. The apparatus of claim 29, wherein reporting the measurement results via a MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction. (Appendix 34) 30. The apparatus of claim 29, wherein reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, beam measurement results, whether there are any available beams, and a number of available beams. (Appendix 35) 35. The apparatus of claim 29 or 34, wherein the MAC CE is different from a BFR MAC CE. (Appendix 36) 36. The apparatus of claim 29, 34 or 35, wherein the MAC CE is periodically triggered and / or event triggered. (Appendix 37) 37. The apparatus of claim 36, wherein the event includes an L1 instruction and / or an L3 instruction. (Appendix 38) 29. The apparatus of claim 28, wherein the L1 signaling is DCI and / or the L2 signaling is MAC CE. (Appendix 39) The L1 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling, or 40. The apparatus of claim 28 or 38, wherein the apparatus indicates at least one of the scheduling information. (Appendix 40) The L2 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L2 signaling, or 40. The apparatus of claim 28 or 38, wherein the apparatus indicates at least one of the scheduling information. (Appendix 41) 29. The apparatus of claim 28, further comprising: a decision unit configured to decide to use a cell change procedure based on L1 signaling and / or L2 signaling, or a cell change procedure based on RRC signaling. (Appendix 42) the cell change procedure based on L1 signaling and / or L2 signaling includes the first network node sending L1 signaling and / or L2 signaling to a terminal device to trigger a serving cell change; and / or 42. The apparatus of claim 41, wherein the RRC signaling-based cell change procedure includes the first network node sending an RRC reconfiguration message to the terminal device to trigger a serving cell change. (Appendix 43) The apparatus of claim 28, further comprising: a third transmitting unit that transmits configuration information of a group of cells to the terminal device. (Appendix 44) 44. The apparatus of claim 28 or 43, further comprising: a first providing unit configured to provide broadcast information and / or an RRC dedicated message including first indication information to the terminal device. (Appendix 45) The first instruction information is the first network node or the cell transmitting the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; The first network node or the cell transmitting the first indication information only supports a cell change procedure based on L3 signaling, or 45. The apparatus of claim 44, wherein the first network node or the cell transmitting the first indication information indicates that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling, and a cell change procedure based on L3 signaling. (Appendix 46) 45. The apparatus of claim 44, wherein the RRC dedicated message explicitly or implicitly indicates support for a cell change procedure based on L1 signaling and / or L2 signaling. (Appendix 47) The RRC dedicated message implicitly indicates that a cell change procedure based on L1 signaling and / or L2 signaling is supported, The apparatus of Supplementary Note 46, further comprising, if configuration information of a group of cells is transmitted to the terminal device, the terminal device assuming that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling. (Appendix 48) A terminal device comprising the device of any one of appendices 1 to 27. (Appendix 49) 48. A network node comprising the apparatus of any one of Supplementary Notes 28 to 47. (Appendix 50) 49. A communication system comprising a terminal device according to claim 48 and / or a network node according to claim 49. (Appendix 2) (Appendix 1) A cell change method applied to a terminal device, comprising: transmitting the measurements to a first network node; receiving L1 signaling and / or L2 signaling from the first network node; and changing from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling. (Appendix 2) transmitting the measurement results to the first network node, 2. The method of claim 1, comprising reporting measurement results via at least one of RRC signaling, L1 signaling, and MAC CE. (Appendix 3) 3. The method according to claim 2, wherein reporting the measurement results via RRC signaling includes a measurement reporting procedure. (Appendix 4) 3. The method of claim 2, wherein reporting the measurement results via L1 signaling includes reporting SSB and / or CSI-RS measurement results via L1 signaling. (Appendix 5) 5. The method of claim 2 or 4, wherein reporting the measurement results via L1 signaling comprises reporting the measurement results periodically and / or reporting the measurement results triggered by an event. (Appendix 6) 3. The method of claim 2, wherein reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam failure. (Appendix 7) 3. The method of claim 2, wherein reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of an available beam, a measurement result of the beam, whether or not there is an available beam, and the number of available beams. (Appendix 8) 8. The method of claim 2 or 7, wherein the MAC CE is different from the BFR MAC CE. (Appendix 9) 9. The method of claim 2, 7 or 8, wherein the MAC CE is periodically triggered and / or event triggered. (Appendix 10) 10. The method of claim 9, wherein the event includes an L1 instruction and / or an L3 instruction. (Appendix 11) 2. The method of claim 1, wherein the L1 signaling is DCI and / or the L2 signaling is MAC CE. (Appendix 12) The L1 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling, or 12. The method of claim 1 or 11, further comprising indicating at least one of the scheduling information. (Appendix 13) The L2 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L2 signaling, or 12. The method of claim 1 or 11, further comprising indicating at least one of the scheduling information. (Appendix 14) The step of changing from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling includes: starting a first timer for controlling a cell change procedure based on the L1 signaling and / or the L2 signaling; applying the indicated configuration of the cell; initiating a random access procedure to the indicated cell; considering the C-RNTI associated with the indicated cell as its own C-RNTI; receiving DL transmission in the cell based on the indicated scheduling information; or 2. The method of claim 1, further comprising at least one of transmitting information to the indicated cell or a network node to which the cell belongs. (Appendix 14a) The method described in Supplementary Note 14, wherein if the terminal device receives the first DL transmission in the indicated cell, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 15) The method described in Supplementary Note 14, wherein if the terminal device applies the configuration of the indicated cell, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 16) Applying the indicated cell configuration 16. The method of claim 14 or 15, comprising applying at least one of an SSB frequency, a TA value, and a physical layer configuration of the cell. (Appendix 17) The method described in Supplementary Note 14, wherein when the terminal device completes the random access procedure, the terminal device considers that the cell change is completed or that the change to the indicated cell is successful. (Appendix 18) The method described in Supplementary Note 14, wherein the information transmitted by the terminal device to the cell or the network node to which the cell belongs indicates that a cell change has been completed or that a change to the indicated cell has been successful. (Appendix 19) transmitting information to the indicated cell or a network node to which the cell belongs, conveying said information in an RRC reconfiguration complete message; Indicating said information by feedback of said L1 signaling and / or said L2 signaling, or 19. The method of claim 14 or 18, comprising at least one of indicating the information by scheduling information indicated by the L1 signaling and / or the L2 signaling. (Appendix 20) A method according to any one of Supplementary Notes 1, 14 to 19, further comprising the step of the terminal device starting communication with the indicated cell and / or stopping the first timer after the cell change is completed or the change to the indicated cell is successful. (Appendix 21) The method described in Supplementary Note 20, wherein the terminal device initiating communication with the indicated cell includes transmitting and receiving a dedicated channel and / or signal of the terminal device, and / or transmitting and receiving a non-dedicated channel and / or signal of the terminal device. (Appendix 22) The method of claim 1 or 14, further comprising the step of the terminal device initiating a connection re-establishment process if the change to the indicated cell fails. (Appendix 23) that the first timer has timed out; A random access procedure initiated by the terminal device to the indicated cell fails or the number of failures reaches a predetermined number; and 23. The method of claim 22, wherein the change to the indicated cell is considered to have failed if at least one of the following occurs: the terminal device is unable to apply the indicated configuration or part of the configuration of the cell. (Appendix 24) 24. The method of any of claims 1 to 23, further comprising receiving configuration information of a group of cells from the first network node. (Appendix 25) 25. The method of claim 1 or 24, wherein if the terminal device receives configuration information of a group of cells, the terminal device assumes that the first network node supports a cell change procedure based on the L1 signaling and / or the L2 signaling. (Appendix 26) 26. The method of claim 1, 24 or 25, further comprising receiving broadcast information and / or an RRC dedicated message comprising first indication information from the first network node. (Appendix 27) The first instruction information is the first network node or the cell transmitting the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; The first network node or the cell transmitting the first indication information only supports a cell change procedure based on L3 signaling, or 27. The method of claim 26, wherein the first network node or the cell transmitting the first indication information indicates that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling, and a cell change procedure based on L3 signaling. (Appendix 28) 1. A cell change method applied in a first network node, comprising: receiving measurement results from a terminal device; and transmitting the L1 signaling and / or the L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling. (Appendix 29) 29. The method of claim 28, wherein the measurement results are reported via at least one of RRC signaling, L1 signaling, and MAC CE. (Appendix 30) 29. The method of claim 29, wherein reporting the measurement results via RRC signaling includes a measurement reporting procedure. (Appendix 31) 30. The method of claim 29, wherein reporting the measurement results via L1 signaling includes reporting SSB and / or CSI-RS measurement results via L1 signaling. (Appendix 32) 32. The method of claim 29 or 31, wherein reporting the measurement results via L1 signaling comprises reporting the measurement results periodically and / or reporting the measurement results triggered by an event. (Appendix 33) 30. The method of claim 29, wherein reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction. (Appendix 34) 29. The method of claim 29, wherein reporting the measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, beam measurement results, whether there are any available beams, and the number of available beams. (Appendix 35) 35. The method of claim 29 or 34, wherein the MAC CE is different from the BFR MAC CE. (Appendix 36) 36. The method of claim 29, 34 or 35, wherein the MAC CE is periodically triggered and / or event triggered. (Appendix 37) 37. The method of claim 36, wherein the event includes an L1 instruction and / or an L3 instruction. (Appendix 38) 29. The method of claim 28, wherein the L1 signaling is DCI and / or the L2 signaling is MAC CE. (Appendix 39) The L1 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling, or 39. The method of claim 28 or 38, indicating at least one of the scheduling information. (Appendix 40) The L2 signaling Cell information, TCI state ID, TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L2 signaling, or 39. The method of claim 28 or 38, indicating at least one of the scheduling information. (Appendix 41) 29. The method of claim 28, further comprising determining to use a cell change procedure based on L1 signaling and / or L2 signaling, or a cell change procedure based on RRC signaling. (Appendix 42) the cell change procedure based on L1 signaling and / or L2 signaling includes the first network node sending L1 signaling and / or L2 signaling to a terminal device to trigger a serving cell change; and / or 42. The method of claim 41, wherein the RRC signaling-based cell change procedure includes the first network node sending an RRC reconfiguration message to a terminal device to trigger a serving cell change. (Appendix 43) 29. The method of claim 28, further comprising the step of transmitting configuration information of a group of cells to the terminal device. (Appendix 44) 44. The method of claim 28 or 43, further comprising the step of providing the terminal device with broadcast information and / or an RRC dedicated message including first indication information. (Appendix 45) The first instruction information is the first network node or the cell transmitting the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; The first network node or the cell transmitting the first indication information only supports a cell change procedure based on L3 signaling, or 45. The method of claim 44, wherein the first network node or the cell transmitting the first indication information indicates that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling, and a cell change procedure based on L3 signaling. (Appendix 46) 45. The method of claim 44, wherein the RRC dedicated message explicitly or implicitly indicates support for a cell change procedure based on L1 signaling and / or L2 signaling. (Appendix 47) The RRC dedicated message implicitly indicates that a cell change procedure based on L1 signaling and / or L2 signaling is supported, 47. The method of claim 46, comprising, if configuration information of a group of cells is transmitted to the terminal device, the terminal device assuming that the first network node supports a cell change procedure based on L1 signaling and / or L2 signaling.

Claims

1. A cell change device disposed in a terminal device, a first transmitter for transmitting the measurement result to a first network node; a first receiver for receiving L1 signaling and / or L2 signaling from the first network node; a first change unit that changes from a serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

2. The apparatus of claim 1 , wherein the first transmitter reports the measurement results via at least one of RRC signaling, L1 signaling, and MAC CE.

3. The apparatus of claim 2 , wherein reporting the measurement results via L1 signaling comprises: periodic reporting of the measurement results; and / or event-triggered reporting of the measurement results.

4. The apparatus of claim 2 , wherein reporting the measurement results via the MAC CE includes reporting available candidate beams via a BFR MAC CE triggered by a beam obstruction.

5. 3. The apparatus of claim 2, wherein reporting measurement results via the MAC CE includes reporting via the MAC CE at least one of an indication of available beams, beam measurement results, whether there are any available beams, and a number of available beams.

6. The L1 signaling and / or the L2 signaling Cell information, TCI state identifier (TCI state ID), TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling and / or the L2 signaling, or The apparatus of claim 1 , wherein the apparatus indicates at least one of the scheduling information.

7. The first change unit is starting a first timer for controlling a cell change procedure based on the L1 signaling and / or the L2 signaling; applying the indicated configuration of the cell; initiating a random access procedure to the indicated cell; considering the C-RNTI associated with the indicated cell as its own C-RNTI; receiving DL transmissions in the cell based on the indicated scheduling information; or 2. The apparatus of claim 1, further comprising: transmitting information to the indicated cell or a network node to which the cell belongs.

8. The device of claim 7, wherein the terminal device considers that the cell change is complete or that the change to the indicated cell is successful when the terminal device receives a first DL transmission in the indicated cell.

9. The device according to claim 7, wherein the terminal device considers that the cell change is completed or that the change to the indicated cell is successful if the terminal device applies the configuration of the indicated cell.

10. The device according to claim 7, wherein the terminal device considers that the cell change is completed or that the change to the indicated cell is successful when the terminal device completes the random access procedure.

11. 8. The apparatus of claim 7, wherein the information transmitted by the terminal device to the cell or to the network node to which the cell belongs indicates that a cell change has been completed or that a change to the indicated cell has been successful.

12. transmitting information to the indicated cell or a network node to which the cell belongs, conveying said information in an RRC reconfiguration complete message; Indicating said information by feedback of said L1 signaling and / or said L2 signaling, or The apparatus of claim 7 , comprising at least one of indicating the information by scheduling information indicated by the L1 signaling and / or the L2 signaling.

13. The device according to claim 1, wherein after the cell change is completed or the change to the indicated cell is successful, the terminal device starts communication with the indicated cell and / or stops the first timer.

14. The device of claim 13, wherein the terminal device initiates communication with the indicated cell, including transmission and reception of dedicated channels and / or signals of the terminal device, and / or transmission and reception of non-dedicated channels and / or signals of the terminal device.

15. 2. The apparatus of claim 1, wherein if the terminal device receives configuration information of a group of cells, the terminal device assumes that the first network node supports a cell change procedure based on the L1 signaling and / or the L2 signaling.

16. The apparatus of claim 1 , further comprising: a third receiver configured to receive broadcast information and / or an RRC dedicated message including the first indication information from the first network node.

17. A cell changing apparatus, applied in a first network node, comprising: a fourth receiving unit that receives the measurement result from the terminal device; and a second transmitting unit that transmits the L1 signaling and / or the L2 signaling to the terminal device to instruct the terminal device to change from the serving cell to a cell indicated by the L2 signaling and / or the L1 signaling.

18. The L1 signaling and / or the L2 signaling Cell information, TCI state identifier (TCI state ID), TA information, a UE identifier assigned for the terminal device by the target cell; HARQ feedback information of the L1 signaling and / or the L2 signaling, or 20. The apparatus of claim 17, wherein the apparatus indicates at least one of the scheduling information.

19. The apparatus according to claim 17 , further comprising: a first providing unit configured to provide broadcast information and / or an RRC dedicated message including first indication information to the terminal device.

20. The first instruction information is the first network node or the cell transmitting the first indication information supports a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information does not support a cell change procedure based on L1 signaling and / or L2 signaling; the first network node or the cell transmitting the first indication information only supports a cell change procedure based on L3 signaling, or 20. The apparatus of claim 19, wherein the first network node or the cell transmitting the first indication information indicates that the first network node or the cell transmitting the first indication information supports at least one of a cell change procedure based on L1 signaling and / or L2 signaling, and a cell change procedure based on L3 signaling.

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