Method and device for supporting cell switching in wireless communication

Abstract

The invention discloses a method and a device for supporting cell switching in wireless communication. A first node receives a first RRC signaling and evaluates whether a first condition set for a second cell is satisfied, the first RRC signaling indicating the second cell and configuration grant of the second cell, the second cell being a handover candidate cell; when the first condition set for the second cell is satisfied, sending a PUSCH in the second cell, the time-frequency resource occupied by the PUSCH being indicated by the configuration grant; wherein the sending timing of the PUSCH is the same as the sending timing of a random access sequence; a time alignment timer associated with a timing advance group to which the second cell belongs is not running; the first condition set comprises that the channel quality of a first cell is poorer than a first threshold value, and the first cell is a service cell of the first node; the PUSCH is used for switching to the second cell. According to the invention, rapid cell switching can be realized.

Description

Technical Field

[0001] The present application relates to methods and devices in wireless communication systems, and more particularly to methods and devices for supporting cell switching in wireless communication. Background Art

[0002] In the future, the application scenarios of wireless communication systems will become more and more diversified, and different application scenarios will put forward different performance requirements for the system. In order to meet the different performance requirements of various application scenarios, the 3GPP (3rd Generation Partner Project) RAN (Radio Access Network) #72 plenary meeting decided to study the new radio technology (NR) (or 5G), and the WI (Work Item) of the new radio technology was passed at the 3GPP RAN #75 plenary meeting, and the standardization work on NR began.

[0003] In the new air interface technology, providing effective mobility support for cell switching is one of the most basic requirements. The basic requirements for cell switching are robustness and low switching delay to reduce the impact on services. In order to adapt to various application scenarios and meet different needs, 3GPP has been evolving cell switching technology. Summary of the invention

[0004] When a UE (User Equipment) moves from the coverage of one cell to the coverage of another cell, it is necessary to change the UE's service cell, that is, switch from the source cell to the target cell. Existing cell switching is usually based on L3 (Layer 3) measurement, and is triggered by the network sending RRC (Radio Resource Control) signaling including reconfiguration with synchronization. The cell switching implemented in L3 has the characteristics of long delay and long service interruption time. In order to overcome the above shortcomings, the 3GPP (3rd Generation Partner Project) RAN (Radio Access Network) #94e plenary meeting decided to start the WI (Work Item) standardization work on the cell switching technology based on L1 / L2 (Layer 1 / Layer 2). The design goal of the cell switching based on L1 / L2 is to achieve fast switching of the UE's service cell. In the network-triggered cell switching, there is also the problem that the robustness of RRC signaling cannot be guaranteed. To overcome the robustness problem, 3GPP RAN introduced UE-triggered cell switching in Rel (version)-17, but these technologies are still implemented based on L3.

[0005] The inventors found through research that the combination of UE-triggered cell switching and L1 / L2-based cell switching needs further research. In response to the above problems, the present application discloses a solution. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily. Although the original intention of the present application is for the Uu air interface, the present application can also be used for the PC5 port. Further, although the original intention of the present application is for the cell switching scenario, the present application is also applicable to other scenarios facing similar problems, including but not limited to multi-antenna systems, multi-TRP (Transmission Reception Point, sending and receiving nodes) systems, capacity enhancement systems, short-range communication systems, unlicensed frequency domain communications, IoT (Internet of Things), URLLC (Ultra Reliable Low Latency Communication, ultra-robust low-latency communication) networks, vehicle networking communications, relay communications, dual-connectivity (dual-connectivity, DC), multi-connectivity (multi-connectivity, MC), etc., to achieve similar technical effects. In addition, the use of a unified solution for different scenarios (including but not limited to V2X scenarios and communication scenarios between terminals and base stations) also helps to reduce hardware complexity and costs. In particular, the interpretation of the terminology, nouns, functions, and variables in this application (unless otherwise specified) can refer to the definitions in the 3GPP specification protocols TS38 series and TS37 series.

[0006] The present application discloses a method in a first node used for wireless communication, characterized by comprising:

[0007] receiving first RRC signaling, and evaluating whether a first set of conditions for a second cell is satisfied, the first RRC signaling indicating the second cell and a configuration grant of the second cell, the second cell being a handover candidate cell;

[0008] When the first condition set for the second cell is met, sending a PUSCH in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant;

[0009] Among them, the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is the service cell of the first node; the PUSCH is used to switch to the second cell.

[0010] As an embodiment, the first RRC (Radio Resource Control) signaling includes a candidate cell (candidate cell) for cell switching and a corresponding candidate configuration (candidate configuration).

[0011] As an embodiment, an evaluation result of whether the first condition set for the second cell is satisfied is used to determine whether to trigger a cell handover to the second cell.

[0012] As an embodiment, the above method can implement UE-triggered cell switching through UE evaluation.

[0013] As an embodiment, the cell switching triggered by the UE can speed up the cell switching process and reduce the cell switching delay.

[0014] As an embodiment, the UE-triggered cell switching can omit the signaling of the network-triggered cell switching.

[0015] As an embodiment, the cell switching triggered by the UE is based on the result of UE measurement and evaluation, which can improve the robustness of the switching.

[0016] As an embodiment, the time alignment timer (timeAlignmentTimer, TAT) associated with the timing advance group to which the second cell belongs is not running, indicating that the first node has not yet obtained uplink time alignment (uplink time aligned) with the second cell.

[0017] As an embodiment, the problem to be solved by the present application is: in a cell switching triggered by a UE, before the uplink time alignment with the second cell is obtained, how to determine the transmission timing of a PUSCH (Physical Uplink Shared Channel).

[0018] The transmission timing in this application means uplink timing for transmission.

[0019] As an embodiment, the solution of the present application is: the sending timing of the PUSCH adopts the sending timing of the random access sequence.

[0020] As an embodiment, in the prior art, before uplink time alignment with the second cell is achieved, the first node does not perform uplink transmission except for random access sequence transmission and MsgA (message A) transmission.

[0021] As an embodiment, the above method uses the sending timing of the random access sequence for the sending timing of the PUSCH on the time-frequency resources indicated by the configured grant (CG) before the uplink time alignment with the second cell is obtained, so as to achieve fast cell switching.

[0022] As an embodiment, the above method can implement RACH-less (no random access channel) cell switching.

[0023] As an embodiment, the above method can accelerate cell switching and reduce service interruption delay.

[0024] As an embodiment, the above method may be backward compatible with network triggered LTM (L1 / L2-triggered mobility) switching.

[0025] As an embodiment, the time-frequency resources occupied by the PUSCH in the above method are indicated by the configuration grant, which can further speed up the cell switching speed.

[0026] As an embodiment, the time-frequency resources occupied by the PUSCH in the above method are indicated by the configuration grant, which can improve the success rate of the base station decoding the PUSCH.

[0027] As an embodiment, the UE-triggered cell switching includes conditional LTM.

[0028] As an embodiment, the conditional LTM means a UE-triggered LTM.

[0029] According to one aspect of the present application, the above method is characterized in that it also includes:

[0030] The transmission timing of the PUSCH is the same as the transmission timing of the random access sequence, including: the time when the PUSCH is started to be sent is earlier than the start time of the time unit occupied by the PUSCH by the timing advance value, and the time when the random access sequence is started to be sent is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value;

[0031] The timing advance value is configured by RRC, or the timing advance value is determined by UE.

[0032] As an embodiment, the timing advance value is configured only through RRC signaling.

[0033] As an embodiment, the timing advance value is independent of receiving a timing advance command.

[0034] As an embodiment, the timing advance value is determined before receiving the timing advance command.

[0035] As an embodiment, the first node does not maintain NTA.

[0036] According to one aspect of the present application, the above method is characterized in that it also includes:

[0037] The PUSCH carries an RRC reconfiguration completion message, and the PUSCH occupies a first available configuration grant opportunity on the second cell after the first condition set for the second cell is met.

[0038] According to one aspect of the present application, the above method is characterized in that it also includes:

[0039] The SS-RSRP of the SSB associated with the PUSCH is higher than a second threshold, and the second threshold is configured for SSB selection in conditional LTM.

[0040] As an embodiment, the above method can improve the success rate of PUSCH transmission.

[0041] As an embodiment, the above method effectively reduces uplink interference to other UEs.

[0042] According to one aspect of the present application, the above method is characterized in that it also includes:

[0043] The first transmitter, in response to the first set of conditions for the second cell being satisfied, begins applying a candidate configuration for the second cell, the candidate configuration including the configuration grant.

[0044] As an embodiment, when the first condition set for the second cell is met, the second cell is a target cell for cell switching.

[0045] According to one aspect of the present application, the above method is characterized in that it also includes:

[0046] The first transmitter sends a first random access sequence on the second cell before the first condition set for the second cell is satisfied, and the sending of the first random access sequence is used to activate the configuration grant.

[0047] As an embodiment, the above method implements early uplink synchronization.

[0048] As an embodiment, the sending of the first random access sequence is triggered by the network, or the sending of the first random access sequence is triggered by the first node.

[0049] As an embodiment, the base station of the first node may measure the first random access sequence to generate a timing advance command.

[0050] As an embodiment, a timing advance command is not received before the first set of conditions for the second cell is met.

[0051] As an embodiment, when a timing advance command is received, the timing advance command is applied to the timing advance group.

[0052] As an embodiment, when a timing advance command is received, the time alignment timer is started.

[0053] According to one aspect of the present application, the above method is characterized in that it also includes:

[0054] The first transmitter sends a second random access sequence on the second cell along with sending the PUSCH.

[0055] As an embodiment, the sending of the second random access sequence is triggered by the first node.

[0056] As an embodiment, the base station of the first node may measure a reference signal included in the PUSCH to generate a timing advance command.

[0057] As an embodiment, the base station of the first node may measure the second random access sequence to generate a timing advance command.

[0058] As an embodiment, the above method can speed up the acquisition of uplink time alignment.

[0059] The present application discloses a method used in a second node of wireless communication, characterized by comprising:

[0060] Sending a first RRC signaling, the first RRC signaling indicating a second cell and a configuration grant of the second cell, the second cell being a handover candidate cell; wherein whether a first condition set for the second cell is satisfied is evaluated; when the first condition set for the second cell is satisfied, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of a random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is maintained by the second node; the PUSCH is used to switch to the second cell;

[0061] or,

[0062] When the first condition set for the second cell is met, PUSCH is received in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; wherein, a first RRC signaling is received, the first RRC signaling indicates the second cell and the configuration grant of the second cell, and the second cell is a switching candidate cell; whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is used to send the first RRC signaling; the PUSCH is used to switch to the second cell.

[0063] As an embodiment, in the above method, the second node maintains the first cell, or the second node maintains the second cell.

[0064] According to one aspect of the present application, the above method is characterized in that it also includes:

[0065] sending a first RRC signaling, where the first RRC signaling indicates a second cell and a configuration grant of the second cell, where the second cell is a handover candidate cell;

[0066] When the first condition set for the second cell is met, receiving a PUSCH in the second cell, the time-frequency resources occupied by the PUSCH being indicated by the configuration grant;

[0067] Among them, whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than the first threshold, and the first cell is maintained by the second node; the PUSCH is used to switch to the second cell.

[0068] As an embodiment, in the above method, the second node maintains the first cell and the second cell.

[0069] According to one aspect of the present application, the above method is characterized in that it also includes:

[0070] The transmission timing of the PUSCH is the same as the transmission timing of the random access sequence, including: the time when the PUSCH is started to be sent is earlier than the start time of the time unit occupied by the PUSCH by the timing advance value, and the time when the random access sequence is started to be sent is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value;

[0071] The timing advance value is configured by RRC, or the timing advance value is determined by UE.

[0072] According to one aspect of the present application, the above method is characterized in that it also includes:

[0073] The PUSCH carries an RRC reconfiguration completion message, and the PUSCH occupies a first available configuration grant opportunity on the second cell after the first condition set for the second cell is met.

[0074] According to one aspect of the present application, the above method is characterized in that it also includes:

[0075] The SS-RSRP of the SSB associated with the PUSCH is higher than a second threshold, and the second threshold is configured for SSB selection in conditional LTM.

[0076] According to one aspect of the present application, the above method is characterized in that it also includes:

[0077] In response to the first set of conditions for the second cell being met, a candidate configuration for the second cell is initially applied, the candidate configuration including the configuration grant.

[0078] According to one aspect of the present application, the above method is characterized in that it also includes:

[0079] Before the first set of conditions for the second cell is satisfied, a first random access sequence is received on the second cell and the configuration grant is activated.

[0080] As an embodiment, the first random access sequence is used to generate a timing advance command.

[0081] As a sub-embodiment of the above embodiment, the timing advance command may be sent through the first cell, or may be sent through the second cell.

[0082] As an embodiment, the above method can effectively utilize air interface resources by activating the configuration grant by receiving the first random access sequence.

[0083] As an embodiment, the configuration grant described in the above method is of enhanced type 1 (type 1) type.

[0084] As an embodiment, the configuration granted in the above method is a type other than type 1 and type 2 (type 2).

[0085] According to one aspect of the present application, the above method is characterized in that it also includes:

[0086] Accompanying the reception of the PUSCH, a second random access sequence is received on the second cell.

[0087] As an embodiment, the first random access sequence is used to generate a timing advance command.

[0088] As a sub-embodiment of the above embodiment, the timing advance command is sent through the second cell.

[0089] The present application discloses a first node used for wireless communication, characterized in that it includes:

[0090] a first receiver, receiving a first RRC signaling, and evaluating whether a first condition set for a second cell is satisfied, the first RRC signaling indicating the second cell and a configuration grant of the second cell, the second cell being a handover candidate cell;

[0091] A first transmitter, when the first condition set for the second cell is satisfied, sends a PUSCH in the second cell, where the time-frequency resources occupied by the PUSCH are indicated by the configuration grant;

[0092] Among them, the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is the service cell of the first node; the PUSCH is used to switch to the second cell.

[0093] The present application discloses a second node used for wireless communication, characterized in that it includes:

[0094] A second transmitter sends a first RRC signaling, wherein the first RRC signaling indicates a second cell and a configuration grant of the second cell, and the second cell is a switching candidate cell; wherein whether a first condition set for the second cell is satisfied is evaluated; when the first condition set for the second cell is satisfied, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of a random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is maintained by the second node; and the PUSCH is used to switch to the second cell;

[0095] or,

[0096] A second receiver receives a PUSCH in the second cell when a first condition set for the second cell is met, and the time-frequency resources occupied by the PUSCH are indicated by a configuration grant; wherein a first RRC signaling is received, the first RRC signaling indicates the second cell and the configuration grant of the second cell, and the second cell is a switching candidate cell; whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is used to send the first RRC signaling; the PUSCH is used to switch to the second cell.

[0097] According to one aspect of the present application, the above method is characterized in that it also includes:

[0098] The second node includes the second transmitter and the second receiver. BRIEF DESCRIPTION OF THE DRAWINGS

[0099] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0100] Figure 1 A signal processing flow chart in a first node according to an embodiment of the present application is illustrated;

[0101] Figure 2 A schematic diagram illustrating a network architecture according to an embodiment of the present application is illustrated;

[0102] Figure 3 A schematic diagram illustrating a wireless protocol architecture of a user plane and a control plane according to an embodiment of the present application;

[0103] Figure 4 A hardware module schematic diagram of a communication device according to an embodiment of the present application is illustrated;

[0104] Figure 5 An example of a wireless signal transmission flow chart according to an embodiment of the present application is provided;

[0105] Figure 6 An example of a PUSCH transmission timing diagram according to an embodiment of the present application is shown;

[0106] Figure 7 A schematic diagram illustrating sending a PUSCH and configuring a grant opportunity according to an embodiment of the present application is illustrated;

[0107] Figure 8A schematic diagram illustrating sending a second random access sequence and sending a PUSCH according to an embodiment of the present application is illustrated;

[0108] Fig. 9 An example structural block diagram of a processing device in a first node according to an embodiment of the present application is shown;

[0109] Fig.10 The structural block diagram of the processing device in the second node according to an embodiment of the present application is illustrated. DETAILED DESCRIPTION

[0110] The technical solution of the present application will be further described in detail below in conjunction with the accompanying drawings. It should be noted that, in the absence of conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

[0111] Example 1

[0112] Embodiment 1 illustrates a signal processing flow chart in a first node according to an embodiment of the present application, as shown in the attached Figure 1 shown.

[0113] In embodiment 1, the first node 100 receives a first RRC signaling in step 101; evaluates whether a first condition set for a second cell is met in step 102; sends a PUSCH in the second cell when the first condition set for the second cell is met in step 103; wherein the first RRC signaling indicates the second cell and a configuration grant of the second cell, and the second cell is a switching candidate cell; the time and frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of a random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is a serving cell of the first node; and the PUSCH is used to switch to the second cell.

[0114] As an embodiment, a first RRC signaling is received on a serving cell of the first node.

[0115] As an embodiment, the service cell of the first node includes a SpCell (Special Cell).

[0116] As an embodiment, the service cell of the first node includes a PCell (Primary Cell).

[0117] As an embodiment, the service cell of the first node includes a SCell (secondary cell).

[0118] As an embodiment, the first RRC signaling is RRCReconfiguration (RRC reconfiguration).

[0119] As an embodiment, the first RRC signaling is LTMConfig (LTM configuration).

[0120] As an embodiment, the first RRC signaling includes ConditionalReconfiguration.

[0121] As an embodiment, the first RRC signaling includes condLTMConfig (conditional LTM configuration).

[0122] As an embodiment, the first RRC signaling includes condRRCReconfig (conditional RRC reconfiguration).

[0123] As an embodiment, the first RRC signaling includes ltm-ReferenceConfiguration (LTM reference configuration).

[0124] As an embodiment, the first RRC signaling includes LTM-Candidate.

[0125] As an embodiment, the first RRC signaling includes ltm-CandidateConfig (LTM candidate configuration).

[0126] As an embodiment, the name of the first RRC signaling includes cond (condition).

[0127] As an embodiment, the first RRC signaling indicates at least one candidate cell and at least one corresponding candidate configuration.

[0128] As an embodiment, each candidate cell in the at least one candidate cell corresponds to a candidate configuration in the at least one candidate configuration.

[0129] As an embodiment, the at least one candidate cell is configured according to a measurement report reported by the first node.

[0130] As an embodiment, the measurement report is a low-layer measurement report.

[0131] As an embodiment, the measurement report is an L1 (layer 1) measurement report.

[0132] As an embodiment, the at least one candidate cell is a handover candidate cell.

[0133] As an embodiment, the first RRC signaling indicates the second cell.

[0134] As an embodiment, the second cell is one of the at least one candidate cell.

[0135] As an embodiment, the second cell is a handover candidate cell.

[0136] As an embodiment, the second cell waits to become a service cell of the first node.

[0137] As an embodiment, the second cell is an SCell (secondary cell) of the first node.

[0138] As an embodiment, the handover candidate cell is used for lower layer cell handover.

[0139] As an embodiment, the handover candidate cell is used for LTM.

[0140] As an embodiment, the handover candidate cell is used for conditional LTM.

[0141] As an embodiment, the first RRC signaling includes an identifier of the second cell.

[0142] As an embodiment, the identifier of the second cell is PhysCellId (physical cell identifier).

[0143] As an embodiment, the identifier of the second cell is candidateCellID (candidate cell identifier).

[0144] As an embodiment, the first RRC signaling indicates a configuration grant (configured grant, CG) of the second cell.

[0145] As an embodiment, the first RRC signaling indicates the candidate configuration of the second cell, and the candidate configuration includes the configuration grant.

[0146] As a sub-embodiment of the above embodiment, the first RRC signaling includes a candidate identifier (candidate ID) to indicate the candidate configuration of the second cell.

[0147] As an embodiment, the candidate configuration is applied to conditional switching.

[0148] As an embodiment, the candidate configuration is applied to conditional LTM.

[0149] As an embodiment, the configuration grant indicates periodic time-frequency resources.

[0150] As an embodiment, the configuration grant is an enhanced type 1 configuration grant.

[0151] As an embodiment, it is evaluated whether a first condition set for the second cell is satisfied.

[0152] As an embodiment, in response to receiving the first RRC signaling, an evaluation is started as to whether the first condition set for the second cell is met.

[0153] As an embodiment, the first condition set for the second cell is network configured.

[0154] As an embodiment, the first condition set includes at least one condition.

[0155] As an embodiment, whether the first condition set is satisfied means whether all conditions in the first condition set are satisfied.

[0156] As a sub-embodiment of the above embodiment, all conditions in the first condition set are met, and the first condition set is met.

[0157] As a sub-embodiment of the above embodiment, if any condition in the first condition set is not satisfied, the first condition set is not satisfied.

[0158] As an embodiment, the first condition set includes conditions for executing conditional switching.

[0159] As an embodiment, the first condition set includes conditions for executing conditional LTM.

[0160] As an embodiment, the first condition set includes an event for executing a conditional LTM.

[0161] As an embodiment, the evaluating whether the first condition set for the second cell is satisfied includes: performing channel measurement for the second cell and evaluating whether the first condition set is satisfied.

[0162] As an embodiment, the first RRC signaling indicates that the candidate configuration for the second cell includes a measurement configuration for the second cell.

[0163] As an embodiment, the measurement configuration for the second cell includes a measurement identifier (measurementID), and the first node performs measurement according to a measurement object (measurement object) indicated by the measurement identifier to determine whether the first condition set is met.

[0164] As an embodiment, the first condition set includes that the channel quality of the first cell is worse than a first threshold.

[0165] As an embodiment, the first cell is a service cell of the first node.

[0166] As an embodiment, the first cell is a source cell of cell switching.

[0167] As an embodiment, the first cell is a PCell.

[0168] As an embodiment, the first cell is a PSCell (Primary SCG (Secondary Cell Group) Cell, primary SCG cell).

[0169] As an embodiment, the first threshold is a measurement value.

[0170] As an embodiment, the first threshold is a configuration value.

[0171] As an embodiment, the first threshold is a value obtained by linearly processing a measurement value and an offset value, and the offset value is configurable.

[0172] As an embodiment, the first condition set includes one condition, and the one condition is that the channel quality of the first cell is worse than the first threshold; wherein the first threshold is the channel quality of the second cell.

[0173] As an embodiment, the first condition set includes a condition, wherein the channel quality of the first cell is worse than the first threshold; wherein the first threshold is the difference between the channel quality of the second cell and an offset value, and the offset value is configured.

[0174] As an embodiment, the first condition set includes two conditions, the first of the two conditions being that the channel quality of the first cell is worse than the first threshold; the second of the two conditions being that the channel quality of the second cell is better than a third threshold; wherein the first threshold is configured by the network, and the third threshold is configured by the network.

[0175] As an embodiment, when the channel quality of one cell is less than a threshold, the channel quality of the one cell is worse than the threshold.

[0176] As an embodiment, when the channel quality of one cell is not greater than a threshold, the channel quality of the one cell is worse than the threshold.

[0177] As an embodiment, when the channel quality of one cell is greater than a threshold, the channel quality of the one cell is better than the threshold.

[0178] As an embodiment, when the channel quality of one cell is not less than a threshold, the channel quality of the one cell is better than the threshold.

[0179] As an embodiment, the channel quality of a cell is represented by RSRP (Reference Signal Received Power), or RSRQ (Reference Signal Received Quality), or RSSI (Received Signal Strength Indicator), or SINR (Signal to Interference & Noise Ratio).

[0180] As an embodiment, the channel quality of a cell is obtained by measuring a reference signal of the cell.

[0181] As an embodiment, the cell measurement is performed at a protocol layer below L3 (Layer 3).

[0182] As an embodiment, the cell measurement is performed at L1 (layer 1).

[0183] As an embodiment, the reference signal is SSB (Synchronization Signal Block).

[0184] As an embodiment, the reference signal is SSB (Synchronization Signals / Physical Broadcast Channel).

[0185] As an embodiment, the reference signal is CSI-RS (Channel Status Information-Reference Signal).

[0186] As an example, the channel quality of a cell is obtained after linear processing of the measurement value of the reference signal for the cell and a configured offset value.

[0187] As a sub - example of the above example, the configured offset value includes at least one of the following four offset values: an offset value specific to a measurement object, an offset value specific to a cell, an offset value for an event, and a hysteresis parameter value for an event.

[0188] As an example, the channel quality of the first cell being worse than the first threshold includes: Mp < Mn; where Mp is the channel quality of the first cell, the first threshold is Mn, and Mn is the channel quality of the second cell.

[0189] As an example, the channel quality of the first cell being worse than the first threshold includes: Mp < Thresh1; where Mp is the channel quality of the first cell, the first threshold is Thresh1, and Thresh1 is configured.

[0190] As an example, the channel quality of the second cell being better than the third threshold includes: Mn > Thresh2; where Mn is the channel quality of the second cell, the third threshold is Thresh2, and Thresh2 is configured.

[0191] As an example, that the channel quality of the first cell is worse than the first threshold includes: Mn + Ofn + Ocn – Hys > Mp + Ofp + Ocp + Off; where the channel quality of the first cell is Mp + Ofp + Ocp + Off; the first threshold is Mn + Ofn + Ocn – Hys; Mp is the result measured for the first cell; Ofp is the offset value dedicated to the measurement object for the first cell; Ocp is the cell-specific offset value for the first cell; Off is the offset value for the event; Mn is the result measured for the second cell; Ofn is the offset value dedicated to the measurement object for the second cell; Ocn is the cell-specific offset value for the second cell; Hys is the hysteresis parameter value for the event; when Mp and Mn are RSRP (Reference Signal Received Power), the units of Mp and Mn are dBm (decibel milliwatt); when Mp and Mn are RSRQ (Reference Signal Received Quality) or RS-SINR (Reference Signal-Signal to Interference & Noise Ratio), the units of Mp and Mn are dB (decibel); the units of Ofn, Ocn, Ofp, Ocp, Hys, and Off are dB.

[0192] As an example, that the channel quality of the first cell is worse than the first threshold includes: Mp + Hys < Thresh1; where the channel quality of the first cell is Mp + Hys, the first threshold is Thresh1; Mp is the result measured for the first cell; Hys is the hysteresis parameter value for the event; Thresh1 is configured.

[0193] As an example, that the channel quality of the second cell is better than the third threshold includes: the channel quality of the second cell is Mn + Ofn + Ocn – Hys, the third threshold is Thresh2; where Mn is the result measured for the second cell; Ofn is the offset value dedicated to the measurement object for the second cell; Ocn is the cell-specific offset value for the second cell; Hys is the hysteresis parameter value for the event; Thresh2 is configured.

[0194] As an embodiment, when the Mp and the Mn are RSRP, the units of the Mp and the Mn are dBm (decibel milliwatt); when the Mp and the Mn are RSRQ or RS (Reference Signal)-SINR, the units of the Mp and the Mn are dB (decibel); the units of the Ofn, the Ocn and the Hys are dB, the unit of the Threshold1 is the same as the unit of the Mp; the unit of the Threshold2 is the same as the unit of the Mn.

[0195] As an embodiment, when the first condition set for the second cell is met, cell switching is triggered.

[0196] As an embodiment, when the first condition set for the second cell is met, PUSCH is sent in the second cell.

[0197] As an embodiment, sending PUSCH means: sending a wireless signal through the PUSCH.

[0198] As an embodiment, sending PUSCH means: sending data carried on the PUSCH channel.

[0199] As an embodiment, the PUSCH is the first uplink transmission on the second cell.

[0200] As an embodiment, the PUSCH is not used for the random access procedure.

[0201] As an embodiment, the PUSCH is not used to send MsgA.

[0202] As an embodiment, the PUSCH is not used to send Msg 3 (message 3) in the random access process.

[0203] As an embodiment, the time-frequency resources occupied by the PUSCH are preconfigured.

[0204] As an embodiment, the time-frequency resources occupied by the PUSCH are not dynamically scheduled.

[0205] As an embodiment, the PUSCH is not associated with PRACH (Physical Random Access CHannel).

[0206] As a sub-embodiment of the above embodiment, the time-frequency resources occupied by the PUSCH and the PRACH are not configured in the same IE (Information element) included in the RRC.

[0207] As an embodiment, after the first condition set for the second cell is met, a random access process is not triggered to be performed before the PUSCH is sent in the second cell.

[0208] As an embodiment, the time-frequency resources occupied by the PUSCH are indicated by the configured grant.

[0209] As an embodiment, the configuration grant indicates time-frequency resources for uplink transmission.

[0210] As an embodiment, the configuration grant includes multiple uplink configuration grants.

[0211] As an embodiment, the time-frequency resources occupied by the PUSCH are indicated by an uplink configuration grant among the multiple uplink configuration grants (uplink configured grant) included in the configuration grant, and the uplink configuration grant is valid.

[0212] As an embodiment, the multiple uplink configuration grants included in the configuration grant occur periodically.

[0213] As an embodiment, the multiple uplink configuration grants included in the configuration grant indicate the same frequency domain resources.

[0214] As an embodiment, the time interval between the time domain resources indicated by any two adjacent uplink configuration grants in the multiple uplink configuration grants is the same; wherein the multiple uplink configuration grants include at least 3 uplink configuration grants.

[0215] As an embodiment, the PUSCH is sent on the time-frequency resources indicated by at least one uplink configuration grant among the multiple uplink configuration grants.

[0216] As an embodiment, the transmission timing of the PUSCH is the same as the transmission timing of the random access sequence.

[0217] As an embodiment, the sending timing of the PUSCH being the same as the sending timing of the random access sequence includes: the sending timing of the PUSCH being the same as the sending timing of the PRACH.

[0218] As an embodiment, the random access sequence is sent through the PRACH in any cell included in the timing advance group to which the second cell belongs.

[0219] As an embodiment, the random access sequence is sent in the second cell via the PRACH.

[0220] As an embodiment, the transmission timing of the PUSCH is the same as the transmission timing of the random access sequence, which includes: the transmission timing of the random access sequence is applied to the transmission timing of the PUSCH.

[0221] As an embodiment, the sending timing of the random access sequence is configured by layer 3 and above protocol layer signaling.

[0222] As an embodiment, the sending timing of the random access sequence is configured by RRC signaling.

[0223] As an embodiment, the sending timing of the random access sequence is determined by the first node.

[0224] As an embodiment, the transmission timing of the PUSCH is the same as the transmission timing of the random access sequence, including: TA The value of is 0.

[0225] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the sending timing of the PUSCH is not dependent on the reception of a timing advance command.

[0226] As a sub-embodiment of the above embodiment, the timing advance command is an Absolute Timing Advance Command (absolute timing advance command).

[0227] As a sub-embodiment of the above embodiment, the timing advance command is a Timing Advance Command (timing advance command).

[0228] As a sub-embodiment of the above embodiment, the timing advance command is carried in a LTM Cell Switch Command (cell switching command).

[0229] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, which includes: the sending timing of the PUSCH depends on the network RRC configuration, or the sending timing of the PUSCH depends on the UE implementation.

[0230] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the sending timing of the PUSCH is independent of the propagation delay between the first node and the sender of the first RRC signaling.

[0231] As an embodiment, the PUSCH is used to switch to the second cell.

[0232] As an embodiment, the PUSCH is used to indicate completion of switching to the second cell.

[0233] As an embodiment, the PUSCH belongs to a cell switching process, and the cell switching process is triggered by the first condition set for the second cell being satisfied.

[0234] As an embodiment, the PUSCH carries a response to the first RRC signaling.

[0235] As an embodiment, the PUSCH is sent as a response to the first set of conditions for the second cell being met.

[0236] As an embodiment, when the PUSCH is sent, the time alignment timer associated with the timing advance group (Timing Advance Group, TAG) to which the second cell belongs is not running.

[0237] As an embodiment, the time alignment timer associated with the timing advance group to which the second cell belongs is not running, including: the first node has not yet obtained uplink synchronization with the second cell.

[0238] As an embodiment, the time alignment timer associated with the timing advance group to which the second cell belongs is not running, including: the first node has not yet obtained uplink time alignment with the second cell.

[0239] As an embodiment, the time alignment timer associated with the timing advance group to which the second cell belongs is not running, including: no timing advance command for the timing advance group to which the second cell belongs is received.

[0240] As an embodiment, the time alignment timer associated with the timing advance group to which the second cell belongs is not running, including: the first node does not measure the timing advance for the timing advance group to which the second cell belongs.

[0241] As an embodiment, the first node is not configured to measure the timing advance for the timing advance group to which the second cell belongs.

[0242] As an embodiment, the first node does not have the ability to measure the timing advance for the timing advance group to which the second cell belongs.

[0243] As an embodiment, the timing advance group includes at least one cell, and the same transmission timing is adopted for the at least one cell included in the timing advance group.

[0244] As an embodiment, the expiration value of the time alignment timer is configurable.

[0245] As an embodiment, the expiration value of the time alignment timer is determined by the UE itself.

[0246] As an embodiment, the expiration value of the time alignment timer is pre-configured or specified.

[0247] As an embodiment, the time alignment timer is maintained in a MAC (Medium Access Control) sublayer.

[0248] In the prior art, when the time alignment timer associated with the timing advance group to which the second cell belongs is not running, the first node is only allowed to send a random access sequence or MsgA in the second cell.

[0249] In the present application, when the time alignment timer associated with the timing advance group to which the second cell belongs is not running, sending the PUSCH for switching on the time-frequency resources indicated by the configuration grant can reduce the switching delay.

[0250] Example 2

[0251] Embodiment 2 illustrates a schematic diagram of a network architecture according to an embodiment of the present application, as shown in the attached Figure 2 shown. Figure 2A diagram illustrating a network architecture 200 for NR 5G, LTE (Long-Term Evolution) and LTE-A (Long-Term Evolution Advanced) systems. The NR 5G, LTE or LTE-A network architecture 200 may be referred to as 5GS (5G System) / EPS (Evolved Packet System) 200 or some other suitable terminology. The 5GS / EPS 200 may include one or more UEs (User Equipment) 201, NG-RAN (Next Generation Radio Access Network) 202, 5GC (5G Core Network) / EPC (Evolved Packet Core) 210, HSS (Home Subscriber Server) / UDM (Unified Data Management) 220 and Internet Services 230. The 5GS / EPS may be interconnected with other access networks, but these entities / interfaces are not shown for simplicity. As shown, 5GS / EPS provides packet switching services, however, those skilled in the art will readily appreciate that the various concepts presented throughout this application can be extended to networks providing circuit switching services or other cellular networks. NG-RAN includes NR Node B (gNB) 203 and other gNBs 204. gNB 203 provides user and control plane protocol terminations toward UE 201. gNB 203 can be connected to other gNBs 204 via an Xn interface (e.g., backhaul). gNB 203 may also be referred to as a base station, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (Basic Service Set, BSS), an extended service set (Extended Service Set, ESS), a TRP (Transmission Reception Point, sending and receiving node) or some other suitable terminology. In a NTN (Non Terrestrial Network, non-terrestrial / satellite network) network, gNB 203 may be a satellite, an aircraft, or a ground base station relayed by a satellite. gNB 203 provides an access point to 5GC / EPC 210 for UE 201.Examples of UE 201 include cellular phones, smart phones, Session Initiation Protocol (SIP) phones, laptop computers, personal digital assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, drones, aircraft, narrowband Internet of Things devices, machine type communication devices, land vehicles, cars, vehicle-mounted devices, vehicle-mounted communication units, wearable devices, or any other similar functional devices. Those skilled in the art may also refer to UE 201 as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable term. gNB203 is connected to 5GC / EPC210 via the S1 / NG interface. 5GC / EPC210 includes MME (Mobility Management Entity) / AMF (Authentication Management Field) / SMF (Session Management Function) 211, other MME / AMF / SMF214, S-GW (Service Gateway) / UPF (User Plane Function) 212, and P-GW (Packet Data Network Gateway) / UPF213. MME / AMF / SMF211 is the control node that handles signaling between UE201 and 5GC / EPC210. ​​In general, MME / AMF / SMF211 provides bearer and connection management. All user IP (Internet Protocol) packets are transmitted through S-GW / UPF212, which itself is connected to P-GW / UPF213. P-GW provides UE IP address allocation and other functions. P-GW / UPF213 is connected to Internet service 230. Internet service 230 includes operator-corresponding Internet protocol services, which may specifically include Internet, Intranet, IMS (IP Multimedia Subsystem) and PS (Packet Switching) streaming services.

[0252] As an embodiment, the UE201 corresponds to the first node in this application.

[0253] As an embodiment, the NR node B203 corresponds to the second node in this application.

[0254] As an embodiment, the gNB203 is a macro cell base station.

[0255] As an embodiment, the gNB203 is a micro cell base station.

[0256] As an embodiment, the gNB203 is a pico cell base station.

[0257] As an embodiment, the gNB203 is a home base station (Femtocell).

[0258] As an embodiment, the gNB203 is a base station device that supports large delay difference.

[0259] As an embodiment, the gNB203 is a flying platform device.

[0260] As an embodiment, the gNB203 is a satellite device.

[0261] As an embodiment, the gNB203 is a testing device (e.g., a transceiver that simulates some functions of a base station, a signaling tester).

[0262] As an embodiment, the wireless link from the UE201 to the gNB203 is an uplink, and the uplink is used to perform uplink transmission.

[0263] As an embodiment, the wireless link from the gNB203 to the UE201 is a downlink, and the downlink is used to perform downlink transmission.

[0264] As an embodiment, the UE201 and the gNB203 are connected via a Uu interface.

[0265] Example 3

[0266] Embodiment 3 illustrates a schematic diagram of a wireless protocol architecture of a user plane and a control plane according to an embodiment of the present application, as shown in the attached figure. Figure 3 shown. Figure 3 is a schematic diagram illustrating an embodiment of a radio protocol architecture for a user plane 350 and a control plane 300, Figure 3The radio protocol architecture of the control plane 300 of the UE and gNB is shown in three layers: Layer 1, Layer 2, and Layer 3. Layer 1 (L1 layer) is the lowest layer and implements various PHY (physical layer) signal processing functions. The L1 layer will be referred to as PHY 301 in this article. Layer 2 (L2 layer) 305 is above PHY 301 and is responsible for the link between the UE and the gNB through PHY 301. The L2 layer 305 includes the MAC (Medium Access Control) sublayer 302, the RLC (Radio Link Control) sublayer 303, and the PDCP (Packet Data Convergence Protocol) sublayer 304, which terminate at the gNB on the network side. The PDCP sublayer 304 provides data encryption and integrity protection. The PDCP sublayer 304 also provides support for inter-zone mobility of UEs between gNBs. The RLC sublayer 303 provides segmentation and reassembly of data packets, and retransmission of lost data packets through ARQ. The RLC sublayer 303 also provides duplicate data packet detection and protocol error detection. The MAC sublayer 302 provides mapping between logical and transport channels and multiplexing of logical channel identities. The MAC sublayer 302 is also responsible for allocating various radio resources (e.g., resource blocks) in a cell between UEs. The MAC sublayer 302 is also responsible for HARQ (Hybrid Automatic Repeat Request) operations. The RRC (Radio Resource Control) sublayer 306 in Layer 3 (L3 layer) in the control plane 300 is responsible for obtaining radio resources (i.e., radio bearers) and configuring the lower layers using RRC signaling between the gNB and the UE. Although not shown in the figure, a V2X layer may also be provided above the RRC sublayer 306 in the control plane 300 of the UE. The V2X layer is responsible for generating a PC5 QoS parameter group and QoS rules based on the received service data or service request, generating a PC5 QoS flow corresponding to the PC5 QoS parameter group, and sending the PC5 QoS flow identifier and the corresponding PC5 QoS parameter group to the AS (Access Stratum) layer for the AS layer to perform QoS processing on the data packets belonging to the PC5 QoS flow identifier; the V2X layer also includes a PC5-S signaling protocol (PC5-Signaling Protocol) sublayer, and the V2X layer is responsible for indicating to the AS layer whether each transmission is a PC5-S transmission or a V2X service data transmission.The wireless protocol architecture of the user plane 350 includes layer 1 (L1 layer) and layer 2 (L2 layer). The wireless protocol architecture in the user plane 350 is substantially the same as the corresponding layers and sublayers in the control plane 300 for the physical layer 351, the PDCP sublayer 354 in the L2 layer 355, the RLC sublayer 353 in the L2 layer 355, and the MAC sublayer 352 in the L2 layer 355, but the PDCP sublayer 354 also provides header compression for upper layer data packets to reduce wireless transmission overhead. The L2 layer 355 in the user plane 350 also includes a SDAP (Service Data Adaptation Protocol) sublayer 356, which is responsible for mapping between QoS (Quality of Service) flows and data radio bearers (DRBs) to support the diversity of services. The wireless protocol architecture of the UE in the user plane 350 may include, at the L2 layer, a SDAP sublayer 356, a PDCP sublayer 354, a portion of or all of the protocol sublayers of the RLC sublayer 353 and the MAC sublayer 352. Although not shown, the UE may also have several upper layers above the L2 layer 355, including a network layer (e.g., an IP layer) terminated at the P-GW on the network side and an application layer terminated at the other end of the connection (e.g., a remote UE, a server, etc.).

[0267] As an example, Figure 3 The wireless protocol architecture in is applicable to the first node in this application.

[0268] As an example, Figure 3 The wireless protocol architecture in is applicable to the second node in this application.

[0269] As an embodiment, the first RRC signaling in the present application is generated in the RRC306.

[0270] As an embodiment, the PUSCH in the present application is generated in the PHY301 or the PHY351.

[0271] As an embodiment, the first random access sequence in the present application is generated in the PHY301 or the PHY351.

[0272] As an embodiment, the second random access sequence in the present application is generated in the PHY301 or the PHY351.

[0273] As an embodiment, the L2 layer 305 or 355 belongs to a higher layer.

[0274] As an embodiment, the RRC sublayer 306 in the L3 layer belongs to a higher layer.

[0275] Example 4

[0276] Embodiment 4 illustrates a hardware module schematic diagram of a communication device according to an embodiment of the present application, as shown in the attached Figure 4 shown. Figure 4 is a block diagram of a first communication device 450 and a second communication device 410 communicating with each other in an access network.

[0277] The first communication device 450 includes a controller / processor 459, a memory 460, a data source 467, a transmit processor 468, a receive processor 456, a multi-antenna transmit processor 457, a multi-antenna receive processor 458, a transmitter / receiver 454 and an antenna 452.

[0278] The second communication device 410 includes a controller / processor 475, a memory 476, a data source 477, a receive processor 470, a transmit processor 416, a multi-antenna receive processor 472, a multi-antenna transmit processor 471, a transmitter / receiver 418 and an antenna 420.

[0279] In the transmission from the second communication device 410 to the first communication device 450, at the second communication device 410, the upper layer data packets from the core network or the upper layer data packets from the data source 477 are provided to the controller / processor 475. The core network and the data source 477 represent all the protocol layers above the L2 layer. The controller / processor 475 implements the functionality of the L2 layer. In the transmission from the second communication device 410 to the first communication device 450, the controller / processor 475 provides header compression, encryption, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocation to the first communication device 450 based on various priority metrics. The controller / processor 475 is also responsible for the retransmission of lost packets and signaling to the first communication device 450. The transmit processor 416 and the multi-antenna transmit processor 471 implement various signal processing functions for the L1 layer (i.e., the physical layer). The transmit processor 416 implements coding and interleaving to facilitate forward error correction (FEC) at the second communication device 410, as well as mapping of signal constellations based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The multi-antenna transmit processor 471 performs digital spatial precoding, including codebook-based precoding and non-codebook-based precoding, and beamforming processing on the coded and modulated symbols to generate one or more spatial streams. The transmit processor 416 then maps each spatial stream to a subcarrier, multiplexes it with a reference signal (e.g., a pilot) in the time domain and / or frequency domain, and then uses an inverse fast Fourier transform (IFFT) to generate a physical channel carrying a time-domain multi-carrier symbol stream. The multi-antenna transmit processor 471 then performs a transmit analog precoding / beamforming operation on the time-domain multi-carrier symbol stream. Each transmitter 418 converts the baseband multi-carrier symbol stream provided by the multi-antenna transmit processor 471 into a radio frequency stream, and then provides it to a different antenna 420.

[0280] In the transmission from the second communication device 410 to the first communication device 450, at the first communication device 450, each receiver 454 receives a signal through its corresponding antenna 452. Each receiver 454 recovers the information modulated onto the RF carrier and converts the RF stream into a baseband multi-carrier symbol stream and provides it to the receiving processor 456. The receiving processor 456 and the multi-antenna receiving processor 458 implement various signal processing functions of the L1 layer. The multi-antenna receiving processor 458 performs a receiving analog precoding / beamforming operation on the baseband multi-carrier symbol stream from the receiver 454. The receiving processor 456 uses a fast Fourier transform (FFT) to convert the baseband multi-carrier symbol stream after the receiving analog precoding / beamforming operation from the time domain to the frequency domain. In the frequency domain, the physical layer data signal and the reference signal are demultiplexed by the receiving processor 456, wherein the reference signal will be used for channel estimation, and the data signal is recovered after multi-antenna detection in the multi-antenna receiving processor 458 to any spatial stream destined for the first communication device 450. The symbols on each spatial stream are demodulated and recovered in the receiving processor 456, and soft decisions are generated. The receiving processor 456 then decodes and deinterleaves the soft decisions to recover the upper layer data and control signals transmitted by the second communication device 410 on the physical channel. The upper layer data and control signals are then provided to the controller / processor 459. The controller / processor 459 implements the functions of the L2 layer. The controller / processor 459 may be associated with a memory 460 that stores program codes and data. The memory 460 may be referred to as a computer-readable medium. In the transmission from the second communication device 410 to the first communication device 450, the controller / processor 459 provides multiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover the upper layer data packets from the second communication device 410. The upper layer data packets are then provided to all protocol layers above the L2 layer. Various control signals may also be provided to the L3 for L3 processing.

[0281] In the transmission from the first communication device 450 to the second communication device 410, at the first communication device 450, the upper layer data packets are provided to the controller / processor 459 using the data source 467. The data source 467 represents all the protocol layers above the L2 layer. Similar to the transmission function at the second communication device 410 described in the transmission from the second communication device 410 to the first communication device 450, the controller / processor 459 implements header compression, encryption, packet segmentation and reordering, and multiplexing between logical and transport channels, and implements L2 layer functions for user plane and control plane. The controller / processor 459 is also responsible for the retransmission of lost packets and signaling to the second communication device 410. The transmit processor 468 performs modulation mapping and channel coding processing, and the multi-antenna transmit processor 457 performs digital multi-antenna spatial precoding, including codebook-based precoding and non-codebook-based precoding, and beamforming processing. Then, the transmit processor 468 modulates the generated spatial stream into a multi-carrier / single-carrier symbol stream, which is then provided to different antennas 452 via the transmitter 454 after analog precoding / beamforming operations in the multi-antenna transmit processor 457. Each transmitter 454 first converts the baseband symbol stream provided by the multi-antenna transmit processor 457 into a radio frequency symbol stream, and then provides it to the antenna 452.

[0282] In the transmission from the first communication device 450 to the second communication device 410, the functions at the second communication device 410 are similar to the reception functions at the first communication device 450 described in the transmission from the second communication device 410 to the first communication device 450. Each receiver 418 receives a radio frequency signal through its corresponding antenna 420, converts the received radio frequency signal into a baseband signal, and provides the baseband signal to the multi-antenna reception processor 472 and the reception processor 470. The reception processor 470 and the multi-antenna reception processor 472 jointly implement the functions of the L1 layer. The controller / processor 475 implements the L2 layer functions. The controller / processor 475 can be associated with a memory 476 that stores program codes and data. The memory 476 can be referred to as a computer-readable medium. In the transmission from the first communication device 450 to the second communication device 410, the controller / processor 475 provides multiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover the upper layer data packets from the first communication device 450. The upper layer data packets from the controller / processor 475 may be provided to the core network or all protocol layers above the L2 layer, and various control signals may also be provided to the core network or L3 for L3 processing.

[0283] As an embodiment, the first communication device 450 apparatus includes: at least one processor and at least one memory, the at least one memory including computer program code; the at least one memory and the computer program code are configured to be used together with the at least one processor, and the first communication device 450 apparatus at least: receives a first RRC signaling, and evaluates whether a first condition set for a second cell is met, the first RRC signaling indicates the second cell and a configuration grant of the second cell, and the second cell is a switching candidate cell; when the first condition set for the second cell is met, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; wherein the sending timing of the PUSCH is the same as the sending timing of a random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is a serving cell of the first node; the PUSCH is used to switch to the second cell.

[0284] As an embodiment, the first communication device 450 apparatus includes: a memory storing a computer-readable instruction program, the computer-readable instruction program generates an action when executed by at least one processor, the action including: receiving a first RRC signaling, and evaluating whether a first condition set for a second cell is met, the first RRC signaling indicating the second cell and the configuration grant of the second cell, the second cell being a switching candidate cell; when the first condition set for the second cell is met, sending a PUSCH in the second cell, the time-frequency resources occupied by the PUSCH being indicated by the configuration grant; wherein the sending timing of the PUSCH is the same as the sending timing of a random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, the first cell is a serving cell of the first node; the PUSCH is used to switch to the second cell.

[0285] As an embodiment, the second communication device 410 device includes: at least one processor and at least one memory, the at least one memory includes computer program code; the at least one memory and the computer program code are configured to be used together with the at least one processor. The second communication device 410 device at least: sends a first RRC signaling, the first RRC signaling indicates a configuration grant of a second cell and the second cell, and the second cell is a handover candidate cell.

[0286] As an embodiment, the second communication device 410 apparatus includes: a memory storing a computer-readable instruction program, wherein the computer-readable instruction program generates an action when executed by at least one processor, and the action includes: sending a first RRC signaling, wherein the first RRC signaling indicates a configuration grant of a second cell and the second cell, and the second cell is a switching candidate cell.

[0287] As an embodiment, the second communication device 410 device includes: at least one processor and at least one memory, the at least one memory including computer program code; the at least one memory and the computer program code are configured to be used together with the at least one processor. The second communication device 410 device at least: when the first condition set for the second cell is met, a PUSCH is received in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant.

[0288] As an embodiment, the second communication device 410 apparatus includes: a memory storing a computer-readable instruction program, wherein the computer-readable instruction program generates actions when executed by at least one processor, and the actions include: when a first condition set for the second cell is met, receiving a PUSCH in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant.

[0289] As an embodiment, the second communication device 410 device includes: at least one processor and at least one memory, the at least one memory includes computer program code; the at least one memory and the computer program code are configured to be used together with the at least one processor. The second communication device 410 device at least: sends a first RRC signaling, the first RRC signaling indicates a second cell and a configuration grant of the second cell, the second cell is a handover candidate cell; when the first condition set for the second cell is met, receives a PUSCH in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant.

[0290] As an embodiment, the second communication device 410 apparatus includes: a memory storing a computer-readable instruction program, wherein the computer-readable instruction program generates an action when executed by at least one processor, and the action includes: sending a first RRC signaling, wherein the first RRC signaling indicates a second cell and a configuration grant of the second cell, and the second cell is a switching candidate cell; when a first condition set for the second cell is met, receiving a PUSCH in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant.

[0291] As an embodiment, the first communication device 450 corresponds to the first node in this application.

[0292] As an embodiment, the second communication device 410 corresponds to the second node in this application.

[0293] As an embodiment, the first communication device 450 is a UE.

[0294] As an embodiment, the first communication device 450 is a relay.

[0295] As an embodiment, the second communication device 410 is a base station device.

[0296] As an embodiment, the second communication device 410 is a distribution unit of a base station.

[0297] As an embodiment, the second communication device 410 is a piece of code in a distributed unit of a base station.

[0298] As an embodiment, at least one of the antenna 420, the transmitter 418, the multi-antenna transmit processor 471, the transmit processor 416 or the controller / processor 475 is used to send the first RRC signaling in the present application.

[0299] As an embodiment, at least one of the antenna 452, the receiver 454, the multi-antenna reception processor 458, the reception processor 456 or the controller / processor 459 is used to receive the first RRC signaling in the present application.

[0300] As an embodiment, at least one of the antenna 452, the transmitter 454, the multi-antenna transmit processor 457, the transmit processor 468 or the controller / processor 459 is used to send the PUSCH in the present application.

[0301] As an embodiment, at least one of the antenna 420, the receiver 418, the multi-antenna reception processor 472, the reception processor 470 or the controller / processor 475 is used to receive the PUSCH in the present application.

[0302] As an embodiment, at least one of the antenna 452, the transmitter 454, the multi-antenna transmit processor 457, the transmit processor 468 or the controller / processor 459 is used to send the first random access sequence in the present application.

[0303] As an embodiment, at least one of the antenna 420, the receiver 418, the multi-antenna reception processor 472, the reception processor 470 or the controller / processor 475 is used to receive the first random access sequence in the present application.

[0304] As an embodiment, at least one of the antenna 452, the transmitter 454, the multi-antenna transmit processor 457, the transmit processor 468 or the controller / processor 459 is used to send the second random access sequence in the present application.

[0305] As an embodiment, at least one of the antenna 420, the receiver 418, the multi-antenna receiving processor 472, the receiving processor 470 or the controller / processor 475 is used to receive the second random access sequence in the present application.

[0306] Example 5

[0307] Embodiment 5 illustrates a wireless signal transmission flow chart according to an embodiment of the present application, as shown in the attached Figure 5 As shown in the attached Figure 5 In the example, the first node N51 and the second transmitter N52 communicate through the first cell, and the first node N51 and the second receiver N53 communicate through the second cell. It is particularly noted that the order in this example does not limit the signal transmission order and implementation order in this application.

[0308] for First node N51 , receiving the first RRC signaling in step S511; evaluating whether the first condition set for the second cell is met in step S512; sending a first random access sequence on the second cell in step S513; determining that the first condition set for the second cell is met in step S514; starting to apply the candidate configuration of the second cell in step S515; and sending PUSCH on the second cell in step S516.

[0309] for The first transceiver N52 , sending the first RRC signaling in step S521.

[0310] for Second transceiver N53 , in step S531, a first random access sequence is received on the second cell; in step S532, a PUSCH is received on the second cell.

[0311] In embodiment 5, a first RRC signaling is received, and an evaluation is made as to whether a first condition set for a second cell is met, the first RRC signaling indicating the second cell and a configuration grant for the second cell, the second cell being a candidate cell for switching; when the first condition set for the second cell is met, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; wherein the sending timing of the PUSCH is the same as the sending timing of a random access sequence; a time alignment timer associated with a timing advance group to which the second cell belongs is not running; the first condition set includes that a channel quality of the first cell is worse than a first threshold, the first cell being a serving cell of the first node; the PUSCH is used for switching to the second cell; as a response to the first condition set for the second cell being met, a candidate configuration for the second cell is started to be applied, the candidate configuration including the configuration grant; before the first condition set for the second cell is met, a first random access sequence is sent on the second cell, and the sending of the first random access sequence is used to activate the configuration grant.

[0312] As an embodiment, the first node N51 communicates with the second transmitter N52 through the first cell.

[0313] As an embodiment, the first node N51 communicates with the second receiver N53 through the second cell.

[0314] As an embodiment, the second transmitter N52 and the second receiver N53 belong to the same gNB-DU (Distributed Unit).

[0315] As an embodiment, the second transmitter N52 and the second receiver N53 belong to two different gNB-DUs respectively, and the two different gNB-DUs are associated with the same gNB-CU (Central Unit).

[0316] As an embodiment, the second transmitter N52 and the second receiver N53 belong to two different gNB-DUs respectively, and the two different gNB-DUs are associated with two different gNB-CUs.

[0317] As an embodiment, the second transmitter N52 and the second receiver N53 belong to the same base station.

[0318] As an embodiment, the second transmitter N52 and the second receiver N53 belong to different base stations.

[0319] As an embodiment, a base station includes a gNB-CU and at least one gNB-DU associated with the gNB-CU, and the gNB-CU is connected to any gNB-DU of the at least one gNB-DU through an F1 interface.

[0320] As an embodiment, the second transmitter N52 belongs to the base station of the first cell; the second receiver N53 belongs to the base station of the second cell.

[0321] As an embodiment, the base station of the first cell and the base station of the second cell are the same base station.

[0322] As an embodiment, the base station of the first cell and the base station of the second cell are different base stations.

[0323] For ease of description, Embodiment 5 illustrates a scenario in which the first RRC signaling is received from the first cell, but the present invention is also applicable to a scenario in which the first RRC signaling is received from a serving cell other than the first cell.

[0324] As an embodiment, before the first condition set for the second cell is met, a first random access sequence is sent on the second cell.

[0325] As an embodiment, the sending of the first random access sequence is used to achieve early uplink synchronization with the second cell.

[0326] As an embodiment, the first random access sequence is dedicated to the first node.

[0327] As an embodiment, the sending of the first random access sequence is used to implement RACH-less switching to the second cell.

[0328] As an embodiment, the first random access sequence is sent on the second cell in response to receiving the first RRC signaling.

[0329] The above method can effectively reduce the cell switching delay.

[0330] The above method can save signaling.

[0331] As an embodiment, the first RRC signaling indicates the air interface resources for sending the first random access sequence on the second cell.

[0332] As a sub-embodiment of the above embodiment, the configuration of the air interface resources used to send the first random access sequence does not belong to the candidate configuration of the second cell.

[0333] As a sub-embodiment of the above embodiment, the configuration of the air interface resources for sending the first random access sequence belongs to the candidate configuration of the second cell; the configuration of the air interface resources for sending the first random access sequence is applied before the first condition set for the second cell is met.

[0334] As an embodiment, the air interface resources include UL (Uplink) / SUL (Supplementary UpLink) indication.

[0335] As an embodiment, the air interface resources include SS (Synchronization Signals) / PBCH (Physical Broadcast Channel) indexes.

[0336] As an embodiment, the air interface resources include a PRACH mask index.

[0337] As an embodiment, the air interface resources include an index of the first random access sequence.

[0338] As an embodiment, the random access sequence in the present application means a random access preamble.

[0339] As an embodiment, a random access sequence is a signature sequence.

[0340] As an embodiment, a random access sequence is a Gold sequence.

[0341] As an embodiment, a random access sequence is an M sequence.

[0342] As an embodiment, a random access sequence is a ZC (Zadoff–Chu) sequence.

[0343] As an embodiment, the first receiver receives a PDCCH (Physical Downlink ControlCHannel) order (command), and the PDCCH order is used to trigger sending the first random access sequence on the second cell.

[0344] As a sub-embodiment of the above embodiment, the PDCCH order includes air interface resources for sending the first random access sequence.

[0345] The above method is more effective when the network controls the sending of the first random access sequence.

[0346] As an embodiment, in response to a second set of conditions for the second cell being satisfied, the first random access sequence is sent on the second cell; wherein the second set of conditions includes that the channel quality of the first cell is worse than a fourth threshold, and the fourth threshold is not less than the first threshold.

[0347] The above method can effectively avoid unnecessary random access sequence transmission.

[0348] As an embodiment, the second condition set includes conditions for triggering the sending of the first random access sequence.

[0349] As an embodiment, the second condition set includes a condition, wherein the channel quality of the first cell is worse than the fourth threshold; wherein the fourth threshold is the channel quality of the second cell.

[0350] As an embodiment, the first condition set includes a condition, wherein the channel quality of the first cell is worse than the fourth threshold; wherein the fourth threshold is the difference between the channel quality of the second cell and an offset value, and the offset value is configured.

[0351] As an embodiment, the first condition set includes two conditions, the first of the two conditions being that the channel quality of the first cell is worse than the fourth threshold; the second of the two conditions being that the channel quality of the second cell is better than the fifth threshold; wherein the fourth threshold is configured by the network, and the fifth threshold is configured by the network.

[0352] As an embodiment, the first condition set is not satisfied when the second condition set is satisfied.

[0353] As an embodiment, the first random access sequence is configured by the base station of the second cell, and then forwarded to the base station of the first cell and sent to the first node through the first cell.

[0354] As an embodiment, after sending the first random access sequence and before the first condition set for the second cell is satisfied, the first node does not receive a timing advance command for a timing advance group to which the second cell belongs.

[0355] As an embodiment, after sending the first random access sequence, the random access process to which the first random access sequence belongs ends.

[0356] As an embodiment, the transmission timing of the PUSCH is the same as the transmission timing of the first random access sequence.

[0357] As an embodiment, the sending of the first random access sequence is used to activate the configuration grant.

[0358] As an embodiment, the second receiver activates the configuration grant when receiving the first random access sequence.

[0359] As an embodiment, the activating the configuration grant includes: reserving the time-frequency resources indicated by the configuration grant for the PUSCH transmission of the first node.

[0360] As an embodiment, the configuration grant is a type 3 configuration grant.

[0361] As an embodiment, the configuration grant is activated by the first node by sending the first random access sequence.

[0362] As an embodiment, when the base station of the first cell and the base station of the second cell are different base stations, the first random access sequence is configured by the base station of the second cell, and then forwarded to the base station of the first cell through the backhaul network, and sent to the first node by the first transceiver N52 through the first cell.

[0363] As an embodiment, when the base station of the first cell and the base station of the second cell are different base stations, the base station of the second cell determines the base station of the serving cell of the sender of the first random access sequence according to the received first random access sequence.

[0364] As an embodiment, the backhaul network is ideal.

[0365] As an embodiment, the backhaul network is non-ideal.

[0366] As an embodiment, when the base station of the first cell and the base station of the second cell are different base stations, the base station of the first cell indicates the base station of the second cell after sending the first RRC signaling; after receiving the indication, the configuration grant is activated.

[0367] As an embodiment, when the base station of the first cell and the base station of the second cell are different base stations, the candidate configuration of the second cell is configured by the base station of the second cell, and then forwarded to the base station of the first cell through the backhaul network, and sent to the first node by the second transmitter N52 through the first cell; when the base station of the second cell sends the candidate configuration of the second cell to the base station of the first cell, the configuration grant is activated.

[0368] As an embodiment, in response to the first set of conditions for the second cell being met, applying a candidate configuration of the second cell begins, the candidate configuration including the configuration grant.

[0369] As an embodiment, the applying the candidate configuration of the second cell includes: the second cell becomes a service cell of the first node.

[0370] As an embodiment, the applying the candidate configuration of the second cell includes: applying the candidate configuration of the second cell to perform at least one of uplink transmission or downlink reception.

[0371] As an embodiment, the candidate configuration includes a ConfiguredGrantConfig IE, and the ConfiguredGrantConfig IE is used to configure the configuration grant.

[0372] Example 6

[0373] Embodiment 6 illustrates a schematic diagram of the transmission timing of a PUSCH according to an embodiment of the present application, as shown in the attached figure. Figure 6 As shown in the attached Figure 6 In the figure, the rectangular box represents the time unit occupied by PUSCH.

[0374] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the timing advance value of the time for starting to send the PUSCH is earlier than the start time of the time unit occupied by the PUSCH, and the timing advance value of the time for starting to send the random access sequence is earlier than the start time of the time unit occupied by the random access sequence.

[0375] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the time for starting to send the PUSCH is earlier than the start time of the time unit occupied by the PUSCH by a timing advance value, and the time for starting to send the random access sequence is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value.

[0376] As an embodiment, the time unit occupied by the PUSCH includes Q1 symbols.

[0377] As an embodiment, the time unit occupied by the random access sequence includes Q2 symbols.

[0378] As an embodiment, Q1 and Q2 are positive integers not less than 1 respectively.

[0379] As an embodiment, Q1 is a positive integer not less than 1 and not greater than 14.

[0380] As an embodiment, the Q1 symbols are continuous in the time domain.

[0381] As an embodiment, the Q2 symbols are continuous in the time domain.

[0382] As an embodiment, the symbol is an OFDM (Orthogonal Frequency Division Multiplexing) symbol.

[0383] As an embodiment, the symbol is a multi-carrier symbol.

[0384] As an embodiment, the symbol is a single carrier symbol.

[0385] As an embodiment, the time unit occupied by the PUSCH is a subframe.

[0386] As an embodiment, the time unit occupied by the PUSCH is a time slot.

[0387] As an embodiment, the time unit occupied by the random access sequence is a time slot.

[0388] As an embodiment, the time unit occupied by the random access sequence is two time slots.

[0389] As an embodiment, the time unit occupied by the random access sequence is a subframe.

[0390] As an embodiment, the time unit occupied by the random access sequence is multiple subframes.

[0391] Specifically, the time unit occupied by the random access sequence is a time slot, and the time unit occupied by the PUSCH is a time slot. The random access sequence occupies time slot k, and the timing advance value is T TA , the random access sequence is T before the start time of time slot kTA Start sending; the PUSCH occupies time slot m, and the timing advance value is also T TA , the PUSCH is T before the start time of time slot m TA Start sending.

[0392] It should be noted that, in the above embodiments, k and m may be the same or different.

[0393] It should be noted that the time unit occupied by the PUSCH and the time unit occupied by the random access sequence may be the same or different.

[0394] Specifically, the time unit occupied by the PUSCH and the time unit occupied by the random access sequence are both a time slot; or, the time unit occupied by the PUSCH is a time slot, and the time unit occupied by the random access sequence is a subframe.

[0395] Specifically, the time unit occupied by the random access sequence is a subframe, and the time unit occupied by the PUSCH is a time slot. The random access sequence occupies subframe k, and the timing advance value is T TA , the random access sequence is T before the start time of subframe k TA Start sending; the PUSCH occupies time slot m, and the timing advance value is also T TA , the PUSCH is T before the start time of time slot m TA Start sending.

[0396] As an embodiment, one subframe includes 1 millisecond (ms).

[0397] As an embodiment, a subframe includes a positive integer number of time slots.

[0398] As an embodiment, the number of time slots included in one subframe depends on subcarrier spacing.

[0399] Specifically, the number of time slots included in a subframe is 2 μ , where the subcarrier spacing is 15×2 μ KHz (kilohertz), the value of μ is an integer from 0 to 6.

[0400] Specifically, one time slot includes 14 OFDM symbols, or one time slot includes 12 OFDM symbols.

[0401] As an embodiment, the PUSCH starts to be sent at the timing advance value before the start of the time unit occupied by the PUSCH.

[0402] As an embodiment, the transmission timing of the PUSCH is earlier than the start time of the time unit occupied by the PUSCH by the timing advance value.

[0403] As an embodiment, the time unit occupied by the random access sequence, or the time unit occupied by the PUSCH, is determined by downlink timing.

[0404] As an embodiment, the downlink timing of the time unit includes the time when downlink reception starts to be performed on the time unit.

[0405] As an embodiment, the downlink timing of the time unit depends on the reception of at least one synchronization signal.

[0406] As an embodiment, the reception of the at least one synchronization signal is used to determine the downlink timing of the time unit.

[0407] As an embodiment, the downlink timing of the time unit is the reception time of the first detected path of the time unit.

[0408] As an embodiment, the method for the downlink timing of the time unit may refer to Chapter 4 of the TS38.213 protocol of the 3GPP standard.

[0409] As an embodiment, the method for the downlink timing of the time unit may refer to Chapter 7 of the TS38.133 protocol of the 3GPP standard.

[0410] As an embodiment, since wireless signals experience different propagation paths when transmitted in the air, the receiver will receive the wireless signals at multiple times, where the earliest received wireless signal corresponds to the first detected path, the second received wireless signal corresponds to the second detected path, and so on.

[0411] As an embodiment, the downlink timing of the time unit is the reception time of the first detected path of the time unit, including: a downlink wireless signal is sent in the time unit, and the downlink timing of the time unit is the reception time of the first detected path of the downlink wireless signal.

[0412] Specifically, taking the time unit as a time slot as an example, a transmitter sends a wireless signal in the time slot, and the time of the first path of the wireless signal received by the first node is the downlink timing of the time slot.

[0413] Specifically, since there are multiple propagation paths for a wireless signal to reach a receiver after being sent from a transmitter, the downlink timing depends on the reception time of the first detected path of the wireless signal.

[0414] As an embodiment, the first detected path is the earliest detected path in terms of time.

[0415] As an embodiment, the timing advance value is configured by RRC.

[0416] As an embodiment, the RRC configuration includes configuration through SIB1 (System Information Block, system information block 1) signaling.

[0417] As an embodiment, the RRC configuration includes configuration through RRC signaling.

[0418] As an embodiment, the timing advance value is configured by the first RRC signaling.

[0419] As an embodiment, the first RRC signaling includes ServingCellConfigCommonSIB (serving cell common configuration-system information block).

[0420] As an embodiment, the first RRC signaling includes ServingCellConfigCommon (serving cell common configuration).

[0421] As an embodiment, the first RRC signaling includes dedicatedSIB1-Delivery (dedicated SIB1 delivery).

[0422] As an embodiment, the timing advance value is determined by the UE.

[0423] As an embodiment, the timing advance value is configured by RRC, or the timing advance value is determined by UE, including: when the RRC configuration indicates the timing advance value, the timing advance value is determined by the RRC configuration; when the RRC configuration does not indicate the timing advance value, the timing advance value is determined by the UE.

[0424] As an embodiment, the timing advance value is independent of the reception of the timing advance command.

[0425] As an embodiment, the timing advance value is independent of uplink transmission in the cells included in the timing advance group.

[0426] As an embodiment, the timing advance value is independent of uplink transmission in the second cell.

[0427] As an embodiment, the timing advance value is independent of downlink measurement in the cells included in the timing advance group.

[0428] As an embodiment, the timing advance value does not depend on downlink measurement in the second cell.

[0429] As an embodiment, the transmission timing of the PUSCH uses the timing advance value.

[0430] As an embodiment, in the calculation of the timing advance value, N TA The value of is 0.

[0431] As an embodiment, the calculation of the timing advance value does not depend on N TA The value of .

[0432] As an embodiment, the timing advance value is configured by RRC, or the timing advance value is determined by UE, including: the timing advance value is Among them, the N TA,offset Indicated by n-TimingAdvanceOffset (timing advance offset). If the n-TimingAdvanceOffset is not configured, the N TA,offset ; Indicated by the three parameters TACommon (common timing advance), TACommonDrift (common timing advance drift), and TACommonDriftVariation (common timing advance drift variation). If these three parameters are not configured, the is 0; Calculated by the configured satellite-ephemeris-related high-level parameters. If the high-level parameters are not configured, the is 0; said Tc=1 / (Δf max ·N f ), where Δf max =480·10 3 Hz(Hertz), N f =4096.

[0433] As an embodiment, the timing advance value is determined by the UE, including: the first node obtains the N defined for the duplex mode and frequency range of the second cell by looking up a table. TA,offset .

[0434] As a sub-embodiment of the above embodiment, the first node is not provided with configuration parameters for obtaining the timing advance value.

[0435] As an embodiment, the timing advance value is 25600×Tc; wherein Tc=1 / (Δf max ·N f ), where Δf max =480·10 3 Hz(Hertz), N f =4096.

[0436] As a sub-embodiment of the above embodiment, the frequency range of the second cell is FR1 (frequency range 1), and the duplex mode is FDD (Frequency Division Duplex) or TDD (Time Division Duplex).

[0437] As a sub-embodiment of the above embodiment, there is neither E-UTRA (Evolved Universal Terrestrial Radio Access)-NR nor NB (narrow-band)-IoT (Internet of Things)-NR coexistence case.

[0438] As a sub-embodiment of the above embodiment, there is no LTE-NR coexistence example.

[0439] As an embodiment, the timing advance value is 39936×Tc; wherein Tc=1 / (Δf max ·N f ), where Δf max =480·10 3 Hz(Hertz), N f =4096.

[0440] As a sub-embodiment of the above embodiment, the frequency range of the second cell is FR1, and the duplex mode is TDD.

[0441] As a sub-embodiment of the above embodiment, there is an example of E-UTRA-NR and / or NB-IoT-NR coexistence.

[0442] As a sub-embodiment of the above embodiment, there is an LTE-NR coexistence example.

[0443] As an embodiment, the timing advance value is 0.

[0444] As a sub-embodiment of the above embodiment, the frequency range of the second cell is FR1, and the duplex mode is FDD.

[0445] As a sub-embodiment of the above embodiment, there is an example of E-UTRA-NR and / or NB-IoT-NR coexistence.

[0446] As a sub-embodiment of the above embodiment, there is an LTE-NR coexistence example.

[0447] As an embodiment, the timing advance value is 13792×Tc; wherein Tc=1 / (Δf max ·N f ), where Δf max =480·10 3 Hz(Hertz), N f =4096.

[0448] As a sub-embodiment of the above embodiment, the second cell frequency range is FR2 (frequency range 2).

[0449] As an embodiment, the timing advance value is applied to the PUSCH.

[0450] As an embodiment, the timing advance value is applied to a random access sequence sent on the second cell, including the first random access sequence and the second random access sequence.

[0451] As an embodiment, the SS-RSRP (Synchronization Signal Reference Signal Received Power) of the SSB (Synchronization Signals / Physical Broadcast Channel (SS / PBCH)) associated with the PUSCH is higher than the second threshold.

[0452] As an embodiment, the SS-RSRP of an SSB is measured for a reference signal of the SSB.

[0453] As an embodiment, the association of the PUSCH with an SSB includes: the multi-antenna transmission parameters of the PUSCH are the same as the multi-antenna reception parameters of the SSB.

[0454] As an embodiment, the PUSCH is associated with an SSB including: a multi-antenna reception parameter of the SSB can be used to infer a multi-antenna transmission parameter of the PUSCH.

[0455] As an embodiment, the PUSCH is associated with an SSB including: a multi-antenna reception parameter of the SSB can be used to determine a multi-antenna transmission parameter of the PUSCH.

[0456] As an embodiment, the multi-antenna receiving parameters and the multi-antenna transmitting parameters respectively include spatial domain filters.

[0457] As an embodiment, the multi-antenna receiving parameters and the multi-antenna transmitting parameters respectively include spatial correlation (SpatialRelation) parameters.

[0458] As an embodiment, the multi-antenna receiving parameters and the multi-antenna transmitting parameters respectively include QCL (Quasi-CoLocation) parameters.

[0459] As an embodiment, the QCL parameters include the QCL type.

[0460] As an embodiment, the QCL parameters include: at least one of {delay spread, Doppler spread, Doppler shift, path loss, average gain, average delay, spatial reception parameters}.

[0461] As an embodiment, the specific definition of the QCL parameters refers to Section 5.1.5 of 3GPP TS 38.214.

[0462] As an embodiment, the second threshold is configurable.

[0463] As an embodiment, the second threshold is preconfigured.

[0464] As an embodiment, the second threshold is configured by the first RRC signaling.

[0465] As an embodiment, the second threshold is determined by the first node itself.

[0466] As an embodiment, the second threshold is configured for SSB selection in the conditional LMT.

[0467] As an embodiment, the second threshold is configured for SSB selection in RACH-less switching.

[0468] As a sub-embodiment of the above two embodiments, the selected SSB is associated with the transmission of the PUSCH on the time-frequency resources indicated by the configuration grant.

[0469] As an embodiment, the name of the second threshold includes RSRP (Reference Signal Received Power)-Threshold SSB (SSB threshold).

[0470] As an embodiment, the second threshold is rach-less-RSRP-ThresholdSSB (no random access channel-SSB reference signal received power threshold).

[0471] As an embodiment, the second threshold is cond-LTM-RSRP-ThresholdSSB (conditional LTM-SSB reference signal received power threshold).

[0472] As an embodiment, the SSB is configured in the first RRC signaling.

[0473] As an embodiment, the candidateBeamRSList (candidate beam reference signal list) included in the first RRC signaling is used to configure the SSB.

[0474] As an embodiment, the SSB associated with the PUSCH is the same as the SSB selected when sending the random access sequence in the second cell.

[0475] As a sub-embodiment of the above embodiment, the second threshold is RSRP-ThresholdSSB (SSB reference signal received power threshold).

[0476] As an embodiment, the SSB associated with the PUSCH is the same as the SSB selected when sending MsgA in the second cell; wherein the sending of the MsgA includes the sending of a random access sequence and the sending of a PUSCH associated with the random access sequence.

[0477] As a sub-embodiment of the above embodiment, the second threshold is msgA-RSRP-ThresholdSSB (message A-SSB reference signal received power threshold).

[0478] Example 7

[0479] Embodiment 7 illustrates a schematic diagram of sending a PUSCH and configuring a grant opportunity according to an embodiment of the present application, as shown in the attached figure. Figure 7 Attached Figure 7In the figure, the rectangular box filled with diagonal lines represents PUSCH transmission.

[0480] As an embodiment, the PUSCH carries an RRC reconfiguration complete (RRCReconfigurationComplete) message.

[0481] As an embodiment, the RRC reconfiguration completion message is the first uplink data sent on the second cell after the first condition set for the second cell is met.

[0482] As an embodiment, the first node completes the conditional LTM cell switching by sending the PUSCH.

[0483] As an embodiment, the PUSCH occupies the first available configuration grant opportunity (CG occasion) on the second cell after the first condition set for the second cell is met.

[0484] As an embodiment, the PUSCH carries the first uplink data sent on the second cell; wherein, the PUSCH occupies the first available configuration grant opportunity on the second cell after the first condition set for the second cell is met, and the first uplink data belongs to DRB (Data Radio Bearer) or SRB (Signaling Radio Bearer).

[0485] As an embodiment, the multiple uplink configuration grants included in the configuration grant respectively correspond to multiple configuration grant opportunities.

[0486] As an embodiment, an air interface resource indicated by an uplink configuration grant corresponds to one configuration grant opportunity.

[0487] As an embodiment, the air interface resources include at least one of time domain resources, frequency domain resources, space domain resources and code domain resources.

[0488] As an embodiment, an available configuration grant opportunity includes: air interface resources corresponding to the configuration grant opportunity are available.

[0489] As an embodiment, an available configuration grant opportunity includes: an uplink transmission performed on the configuration grant opportunity has a transmission priority.

[0490] As an embodiment, an available configuration grant opportunity includes: the SS-RSRP of the SSB selected for uplink transmission on the configuration grant opportunity is greater than the second threshold.

[0491] Available in this application means valid.

[0492] Unavailable in this application means not valid.

[0493] As an embodiment, the first node sends the PUSCH on the time-frequency resources indicated by the configuration grant only after the first set of conditions for the second cell is met.

[0494] In case A of Example 7, the first available configuration grant opportunity for sending the PUSCH is the second CG (configured grant) opportunity after the first condition set for the second cell is met; wherein, the first CG (configured grant) opportunity after the first condition set for the second cell is met is not available.

[0495] In case B of embodiment 7, the first available configured grant opportunity for sending the PUSCH is the first CG (configured grant) opportunity after the first condition set for the second cell is met.

[0496] As an embodiment, after applying the candidate configuration for the second cell, a first operation set is started; wherein the first operation set includes at least one of monitoring PDCCH (Physical Downlink Control Channel) on the second cell, monitoring PDCCH used to schedule the second cell, and sending PRACH (Physical Random Access Channel) on the second cell.

[0497] Example 8

[0498] Embodiment 8 illustrates a schematic diagram of sending a second random access sequence and sending a PUSCH according to an embodiment of the present application, as shown in the attached figure. Figure 8 shown.

[0499] As an embodiment, the candidate configuration of the second cell includes air interface resources for sending a second random access sequence.

[0500] As an embodiment, the second random access sequence is sent on the second cell along with the PUSCH.

[0501] As an embodiment, before sending the second random access sequence, the first condition set for the second cell is met.

[0502] As an embodiment, the transmission timing of the PUSCH is the same as the transmission timing of the second random access sequence.

[0503] As an embodiment, the sending of the second random access sequence on the second cell along with the sending of the PUSCH includes: sending the second random access sequence on the second cell immediately after sending the PUSCH.

[0504] As an embodiment, sending the second random access sequence on the second cell along with sending the PUSCH includes: sending the second random access sequence on the second cell immediately followed by sending the PUSCH.

[0505] As an embodiment, the sending of the second random access sequence on the second cell along with the sending of the PUSCH includes: when the PUSCH is not successfully sent, sending the second random access sequence on the second cell.

[0506] As an embodiment, when no ACK (ACKnowledgement) feedback for the PUSCH is received, the PUSCH is not successfully sent.

[0507] As an embodiment, when a NACK (Negative ACK nowledgment) feedback for the PUSCH is received, the PUSCH is not successfully sent.

[0508] As an embodiment, when a PDCCH is not received, the PDCCH schedules a new uplink transmission and indicates the same HARQ (Hybrid Automatic Repeat Request) process as the PUSCH, the PUSCH is not successfully sent.

[0509] As an embodiment, the accompanying sending of the PUSCH and sending the second random access sequence on the second cell include: sending the PUSCH when a random access response to the second random access sequence sent on the second cell is not received; wherein the random access response includes a timing advance command.

[0510] As an embodiment, sending the second random access sequence on the second cell along with sending the PUSCH includes: sending the PUSCH before the random access process to which the second random access sequence belongs is successfully completed.

[0511] As an embodiment, the arrival of uplink data and uplink desynchronization are used to trigger the sending of the second random access sequence.

[0512] As an embodiment, the uplink data is layer 3 and above protocol layer data.

[0513] As an embodiment, the uplink data belongs to DRB, or SRB.

[0514] As an embodiment, the uplink data is an RRC reconfiguration completion message.

[0515] As an embodiment, the time alignment timer associated with the timing advance group to which the second cell belongs is not running, indicating uplink desynchronization.

[0516] In this application, uplink desynchronization and uplink time misalignment can be used interchangeably.

[0517] In case A of Example 8, after the first condition set for the second cell is met, the second random access sequence is sent before sending the PUSCH, that is, the CG opportunity occupied by the PUSCH is later than the time domain resources for sending the second random access sequence.

[0518] In case B of Example 8, after the first condition set for the second cell is met, the second random access sequence is sent after sending the PUSCH, that is, the CG opportunity occupied by the PUSCH is earlier than the time domain resources for sending the second random access sequence.

[0519] Example 9

[0520] Embodiment 9 illustrates a structural block diagram of a processing device in a first node according to an embodiment of the present application, as shown in the attached figure. Fig. 9 As shown in the attached Fig. 9 In the embodiment, the first node processing device 9 includes a first receiver 901 and a first transmitter 902; the first node 900 is a UE.

[0521] In Example 9, a first receiver 901 receives a first RRC signaling and evaluates whether a first condition set for a second cell is met, the first RRC signaling indicating the second cell and a configuration grant of the second cell, and the second cell is a switching candidate cell; a first transmitter 902 sends a PUSCH in the second cell when the first condition set for the second cell is met, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; wherein the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is a serving cell of the first node; and the PUSCH is used to switch to the second cell.

[0522] As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the time for starting to send the PUSCH is earlier than the start time of the time unit occupied by the PUSCH by a timing advance value, and the time for starting to send the random access sequence is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value; wherein, the timing advance value is configured by RRC, or the timing advance value is determined by UE.

[0523] As an embodiment, the PUSCH carries an RRC reconfiguration completion message, and the PUSCH occupies a first available configuration grant opportunity on the second cell after the first condition set for the second cell is met.

[0524] As an embodiment, the SS-RSRP of the SSB associated with the PUSCH is higher than a second threshold, and the second threshold is configured for SSB selection in conditional LTM.

[0525] As an embodiment, the first transmitter 902, in response to the first set of conditions for the second cell being met, starts applying a candidate configuration of the second cell, the candidate configuration including the configuration grant.

[0526] As an embodiment, the first transmitter 902 sends a first random access sequence on the second cell before the first condition set for the second cell is satisfied, and the sending of the first random access sequence is used to activate the configuration grant.

[0527] As an embodiment, the first transmitter 902 sends a second random access sequence on the second cell along with sending the PUSCH.

[0528] As an embodiment, the first receiver 901 includes the attached Figure 4 The receiver 454 (including antenna 452), receive processor 456, multi-antenna receive processor 458 and controller / processor 459.

[0529] As an embodiment, the first receiver 901 includes the attached Figure 4 At least one of the receiver 454 (including antenna 452), receive processor 456, multi-antenna receive processor 458 or controller / processor 459.

[0530] As an embodiment, the first transmitter 902 includes the attached Figure 4 The transmitter 454 (including antenna 452), transmit processor 468, multi-antenna transmit processor 457 and controller / processor 459.

[0531] As an embodiment, the first transmitter 902 includes the attached Figure 4 At least one of the receiver 454 (including antenna 452), transmit processor 468, multi-antenna transmit processor 457 or controller / processor 459.

[0532] Example 10

[0533] Embodiment 10 illustrates a structural block diagram of a processing device in a second node according to an embodiment of the present application, as shown in the attached figure. Fig.10 As shown in the attached Fig.10 In the figure, the dotted box indicates that it is optional, the second node processing device 1000 includes a second receiver 1001, or the second node processing device 1000 includes a second transmitter 1002, or the second node processing device 1000 includes a second receiver 1001 and a second transmitter 1002; the second node 1000 is a base station.

[0534] In embodiment 10, the second transmitter 1002 sends a first RRC signaling, the first RRC signaling indicates a second cell and a configuration grant of the second cell, the second cell is a switching candidate cell; wherein whether a first condition set for the second cell is satisfied is evaluated; when the first condition set for the second cell is satisfied, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is maintained by the second node; the PUSCH is used to switch to the second cell;

[0535] or,

[0536] The second receiver 1001 receives a PUSCH in the second cell when a first condition set for the second cell is met, and the time-frequency resources occupied by the PUSCH are indicated by a configuration grant; wherein a first RRC signaling is received, the first RRC signaling indicates the second cell and the configuration grant of the second cell, and the second cell is a switching candidate cell; whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is used to send the first RRC signaling; and the PUSCH is used to switch to the second cell.

[0537] As an embodiment, the second node includes the second transmitter 1002 and the second receiver 1001. As an embodiment, the sending timing of the PUSCH is the same as the sending timing of the random access sequence, including: the time of starting to send the PUSCH is earlier than the start time of the time unit occupied by the PUSCH by a timing advance value, and the time of starting to send the random access sequence is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value; wherein the timing advance value is configured by RRC, or the timing advance value is determined by UE.

[0538] As an embodiment, the PUSCH carries an RRC reconfiguration completion message, and the PUSCH occupies a first available configuration grant opportunity on the second cell after the first condition set for the second cell is met.

[0539] As an embodiment, the SS-RSRP of the SSB associated with the PUSCH is higher than a second threshold, and the second threshold is configured for SSB selection in conditional LTM.

[0540] As an embodiment, in response to the first set of conditions for the second cell being met, a candidate configuration of the second cell begins to be applied, the candidate configuration including the configuration grant.

[0541] As an embodiment, the second receiver 1001 receives a first random access sequence on the second cell and activates the configuration grant before the first condition set for the second cell is met.

[0542] As an embodiment, the second receiver 1001 receives a second random access sequence on the second cell along with receiving the PUSCH.

[0543] As an embodiment, the second receiver 1001 includes the attached Figure 4 The receiver 418 (including antenna 420), receive processor 470, multi-antenna receive processor 472 and controller / processor 475.

[0544] As an embodiment, the second receiver 1001 includes the attached Figure 4 At least one of the receiver 418 (including the antenna 420), the receive processor 470, the multi-antenna receive processor 472 or the controller / processor 475.

[0545] As an embodiment, the second transmitter 1002 includes the attached Figure 4 The transmitter 418 (including antenna 420), transmit processor 416, multi-antenna transmit processor 471 and controller / processor 475.

[0546] As an embodiment, the second transmitter 1002 includes the attached Figure 4 At least one of the transmitter 418 (including antenna 420), the transmit processor 416, the multi-antenna transmit processor 471 or the controller / processor 475.

[0547] A person of ordinary skill in the art can understand that all or part of the steps in the above method can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium, such as a read-only memory, a hard disk or an optical disk. Optionally, all or part of the steps in the above embodiment can also be implemented using one or more integrated circuits. Accordingly, each module unit in the above embodiment can be implemented in the form of hardware or in the form of a software function module, and the present application is not limited to any specific form of software and hardware combination. The first type of communication node or UE or terminal in the present application includes but is not limited to mobile phones, tablet computers, notebooks, Internet cards, low-power devices, eMTC (enhanced Machine Type Communication, enhanced machine type communication) equipment, NB-IoT equipment, vehicle-mounted communication equipment, aircraft, airplanes, drones, remote-controlled aircraft and other wireless communication equipment. The second type of communication node or base station or network side equipment in the present application includes but is not limited to macrocellular base stations, microcellular base stations, home base stations, relay base stations, eNB, gNB, transmission and reception nodes TRP (Transmission and Reception Point, transmission and reception point), relay satellites, satellite base stations, aerial base stations and other wireless communication equipment.

[0548] The above is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A first node used for wireless communication, characterized in that: include: a first receiver, receiving a first RRC signaling, and evaluating whether a first condition set for a second cell is satisfied, the first RRC signaling indicating the second cell and a configuration grant of the second cell, the second cell being a handover candidate cell; A first transmitter, when the first condition set for the second cell is satisfied, sends a PUSCH in the second cell, where the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; Among them, the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is the service cell of the first node; the PUSCH is used to switch to the second cell.

2. The first node according to claim 1, characterized in that: The transmission timing of the PUSCH is the same as the transmission timing of the random access sequence, including: the time when the PUSCH is started to be sent is earlier than the start time of the time unit occupied by the PUSCH by the timing advance value, and the time when the random access sequence is started to be sent is earlier than the start time of the time unit occupied by the random access sequence by the timing advance value; The timing advance value is configured by RRC, or the timing advance value is determined by UE.

3. The first node according to claim 1 or 2, characterized in that: The PUSCH carries an RRC reconfiguration completion message, and the PUSCH occupies a first available configuration grant opportunity on the second cell after the first condition set for the second cell is met.

4. The first node according to any one of claims 1 to 3, characterized in that: The SS-RSRP of the SSB associated with the PUSCH is higher than a second threshold, and the second threshold is configured for SSB selection in conditional LTM.

5. The first node according to any one of claims 1 to 4, characterized in that: include: The first transmitter, in response to the first set of conditions for the second cell being satisfied, begins applying a candidate configuration for the second cell, the candidate configuration including the configuration grant.

6. The first node according to any one of claims 1 to 5, characterized in that: include: The first transmitter sends a first random access sequence on the second cell before the first condition set for the second cell is satisfied, and the sending of the first random access sequence is used to activate the configuration grant.

7. The first node according to any one of claims 1 to 6, characterized in that: include: The first transmitter sends a second random access sequence on the second cell along with sending the PUSCH.

8. A second node used for wireless communication, characterized in that: include: A second transmitter sends a first RRC signaling, where the first RRC signaling indicates a second cell and a configuration grant of the second cell, where the second cell is a handover candidate cell; Wherein, whether a first condition set for the second cell is satisfied is evaluated; when the first condition set for the second cell is satisfied, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is maintained by the second node; the PUSCH is used to switch to the second cell; or, a second receiver, receiving a PUSCH in the second cell when a first condition set for the second cell is satisfied, wherein the time-frequency resources occupied by the PUSCH are indicated by a configuration grant; Among them, a first RRC signaling is received, the first RRC signaling indicates the second cell and the configuration grant of the second cell, the second cell is a switching candidate cell; whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is used to send the first RRC signaling; the PUSCH is used to switch to the second cell.

9. The second node according to claim 8, characterized in that: The second node includes the second transmitter and the second receiver.

10. A method in a first node for wireless communication, characterized in that: include: receiving first RRC signaling, and evaluating whether a first set of conditions for a second cell is satisfied, the first RRC signaling indicating the second cell and a configuration grant of the second cell, the second cell being a handover candidate cell; When the first condition set for the second cell is met, sending a PUSCH in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; Among them, the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is the service cell of the first node; the PUSCH is used to switch to the second cell.

11. A method in a second node for wireless communication, characterized in that: include: sending a first RRC signaling, where the first RRC signaling indicates a second cell and a configuration grant of the second cell, where the second cell is a handover candidate cell; Wherein, whether a first condition set for the second cell is satisfied is evaluated; when the first condition set for the second cell is satisfied, a PUSCH is sent in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is maintained by the second node; the PUSCH is used to switch to the second cell; or, When the first condition set for the second cell is satisfied, a PUSCH is received in the second cell, and the time-frequency resources occupied by the PUSCH are indicated by the configuration grant; Among them, a first RRC signaling is received, the first RRC signaling indicates the second cell and the configuration grant of the second cell, the second cell is a switching candidate cell; whether the first condition set for the second cell is met is evaluated; the sending timing of the PUSCH is the same as the sending timing of the random access sequence; the time alignment timer associated with the timing advance group to which the second cell belongs is not running; the first condition set includes that the channel quality of the first cell is worse than a first threshold, and the first cell is used to send the first RRC signaling; the PUSCH is used to switch to the second cell.

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