Mobility management

Abstract

The invention relates to mobility management. In accordance with an example aspect of the present disclosure, there is provided an apparatus configured to: receive configuration information related to reporting an early timing advance (TA) acquisition, receive at least one instruction to acquire at least one TA value of at least one candidate cell, generate an early timing advance acquisition report based on the at least one TA value and based on the configuration information; and transmitting an indication indicating the availability of the early TA acquisition report.

Description

Technical Field

[0001] The present disclosure relates to mobility management in wireless communication networks, such as cellular communication networks. Background Art

[0002] Cell changes in cellular communication networks are necessary to provide continuous service to User Equipments, UE, that move from cell to cell or beam to beam within the coverage area of ​​the network.

[0003] A cell change causes signaling overhead as well as communication disruption since measurements are made on the same frequency used for serving cell communications and also on other frequencies. Summary of the invention

[0004] According to some aspects, the subject matter of independent claims is provided. Some embodiments are defined in the independent claims. The scope of protection sought by various embodiments of the present invention is set forth by the independent claims. The embodiments, examples and features (if any) described in this specification that do not belong to the scope of the independent claims will be interpreted as examples that can be used to understand the various embodiments of the present invention.

[0005] According to a first aspect of the present disclosure, a device is provided, comprising at least one processing core and at least one memory storing instructions, which, when executed by the at least one processing core, causes the device to at least: receive configuration information related to the acquisition of an early timing advance TA for reporting, receive at least one instruction for acquiring at least one TA value for at least one candidate cell, generate an early timing advance acquisition report based on the at least one TA value and based on the configuration information; and transmit an indication indicating the availability of an early TA acquisition report.

[0006] According to a second aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory storing instructions, and when the at least one processing core executes these instructions, the device at least: receives configuration information related to the acquisition of an early timing advance TA for reporting via a transceiver of a user equipment, receives at least one instruction for acquiring at least one TA value of at least one candidate cell via the transceiver of the user equipment, generates an early timing advance acquisition report based on at least one TA value and based on the configuration information, and instructs the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report.

[0007] According to a third aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory for storing instructions, and when the at least one processing core executes these instructions, the device at least receives at least one timing advance TA acquisition criterion and early timing advance acquisition report configuration, provides configuration information related to reporting early TA acquisition to a user equipment, wherein the configuration information includes at least one of the TA acquisition criterion or the timing advance acquisition report configuration, determines whether a TA acquisition condition is met based on the configuration information, and sends at least one instruction to the user equipment for acquiring at least one TA value of at least one candidate cell.

[0008] According to a fourth aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory for storing instructions, and when the at least one processing core executes these instructions, the device at least: prepares at least one target cell related to a user equipment served by a base station, and the device is included in the base station; generates configuration information, the configuration information includes at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration, and provides the configuration information to a distributed unit of the base station.

[0009] According to a fifth aspect of the present disclosure, a method is provided, comprising: receiving configuration information related to reporting early timing advance TA acquisition, receiving at least one instruction for acquiring at least one TA value of at least one candidate cell, generating an early timing advance acquisition report based on at least one TA value and based on the configuration information, and transmitting an indication indicating the availability of an early TA acquisition report.

[0010] According to a sixth aspect of the present disclosure, a method is provided, comprising: receiving, via a transceiver of a user equipment, configuration information related to the acquisition of an early timing advance TA for reporting; receiving, via a transceiver of the user equipment, at least one instruction for acquiring at least one TA value of at least one candidate cell, generating an early timing advance acquisition report based on at least one TA value and based on the configuration information, and instructing the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report.

[0011] According to a seventh aspect of the present disclosure, a method is provided, comprising: receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration, providing configuration information related to reporting early TA acquisition to a user equipment, wherein the configuration information includes at least one of the TA acquisition criterion or the timing advance acquisition report configuration, determining whether a TA acquisition condition is met based on the configuration information, and sending at least one instruction to the user equipment for acquiring at least one TA value of at least one candidate cell.

[0012] According to the eighth aspect of the present disclosure, a method is provided, comprising: preparing at least one target cell related to a user equipment served by a base station, the device being included in the base station, generating configuration information, the configuration information comprising at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration, and providing the configuration information to a distributed unit of the base station.

[0013] According to the ninth aspect of the present disclosure, a non-transitory computer-readable medium is provided, on which a set of computer-readable instructions are stored. When the computer-readable instructions are executed by at least one processor, the device causes at least one device to receive configuration information related to reporting early timing advance TA acquisition, receive at least one instruction for acquiring at least one TA value of at least one candidate cell, generate an early timing advance acquisition report based on at least one TA value and based on the configuration information, and transmit an indication indicating the availability of an early TA acquisition report.

[0014] According to the tenth aspect of the present disclosure, a non-transitory computer-readable medium is provided, on which a set of computer-readable instructions are stored, and when the computer-readable instructions are executed by at least one processor, the device at least: receives configuration information related to reporting early timing advance TA acquisition via a transceiver of a user equipment, receives at least one instruction for acquiring at least one TA value of at least one candidate cell via the transceiver of the user equipment, generates an early timing advance acquisition report based on at least one TA value and based on the configuration information, and instructs the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report.

[0015] According to the eleventh aspect of the present disclosure, a non-transitory computer-readable medium is provided, on which a set of computer-readable instructions are stored, and when the computer-readable instructions are executed by at least one processor, the device causes the device to at least: receive at least one timing advance TA acquisition criterion and early timing advance acquisition report configuration, provide configuration information related to reporting early TA acquisition to a user equipment, wherein the configuration information includes at least one of the TA acquisition criterion or the timing advance acquisition report configuration, determine whether the TA acquisition condition is met based on the configuration information, and send at least one instruction to the user equipment to obtain at least one TA value of at least one candidate cell.

[0016] According to the twelfth aspect of the present disclosure, a non-transitory computer-readable medium is provided, on which a set of computer-readable instructions are stored, and when the computer-readable instructions are executed by at least one processor, the device causes the device to at least: prepare at least one target cell related to a user equipment served by a base station, the device being included in the base station, generate configuration information, the configuration information including at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration, and provide the configuration information to a distributed unit of the base station.

[0017] According to the thirteenth aspect of the present disclosure, a method is provided, comprising components for: receiving configuration information related to reporting early timing advance TA acquisition, receiving at least one instruction for acquiring at least one TA value of at least one candidate cell, generating an early timing advance acquisition report based on at least one TA value and based on the configuration information, and sending an indication indicating the availability of an early TA acquisition report.

[0018] According to the fourteenth aspect of the present disclosure, a method is provided, comprising components for: receiving configuration information related to reporting early timing advance TA acquisition via a transceiver of a user equipment, receiving at least one instruction for acquiring at least one TA value of at least one candidate cell via the transceiver of the user equipment, generating an early timing advance acquisition report based on at least one TA value and based on the configuration information, and instructing the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report.

[0019] According to the fifteenth aspect of the present disclosure, a method is provided, comprising components for: receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration, providing configuration information related to reporting early TA acquisition to a user equipment, wherein the configuration information includes at least one of the TA acquisition criterion or the timing advance acquisition report configuration, determining whether a TA acquisition condition is met based on the configuration information, and transmitting to the user equipment at least one instruction for acquiring at least one TA value of at least one candidate cell.

[0020] According to the sixteenth aspect of the present disclosure, a method is provided, comprising components for: preparing a path for at least one target cell associated with a user equipment served by a base station, the device being included in the base station, generating configuration information including at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration, and providing the configuration information to a distributed unit of the base station. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 An example system is shown in accordance with at least some embodiments of the present invention;

[0022] Figure 2A is the coverage map of beams in a cellular communication system;

[0023] Figure 2B is the coverage map of beams in a cellular communication system;

[0024] Figure 2C is the coverage map of beams in a cellular communication system;

[0025] Figure 3 An example apparatus capable of supporting at least some embodiments of the present invention is shown;

[0026] Figure 4 shows signaling according to at least some embodiments of the present invention;

[0027] Figure 5 is a flow chart of a method according to at least some embodiments of the present invention;

[0028] Figure 6 is a flow chart of a method according to at least some embodiments of the present invention;

[0029] Figure 7 is a flow chart of a method according to at least some embodiments of the present invention; and

[0030] Figure 8 is a flow chart of a method according to at least some embodiments of the present invention. DETAILED DESCRIPTION

[0031] Methods are described herein for enhancing the quality of cell switching by reducing the number of unnecessary interruptions due to the acquisition of timing advances for candidate cells during physical layer triggered mobility. A reporting mechanism is disclosed herein that enables the network to adapt its behavior to the contours of the coverage area of ​​each cell, sector or beam in the real terrain. Thus, a technical effect in the form of smoother cell changes and less unnecessary signaling, interruptions and measurements is obtained.

[0032] Figure 1 An example system according to at least some embodiments of the present invention is shown. The system includes a base station 130, a base station 135 communicating with a UE such as UE 110. A radio link connects the base station 130 with the UE 110, and the radio link may be bidirectional, including an uplink UL for transmitting information from the UE 110 to the base station 130, and a downlink DL for transmitting information from the base station 130 to the UE 110.

[0033] The base station 130 is also communicatively coupled to a core network node 140, which may include, for example, a mobility management entity MME or an access and mobility management function AMF. The core network node 140 may be coupled to other core network nodes and a network 150, which may include, for example, the Internet or a corporate network. The system may communicate with other networks via the network 150. For clarity, the following are not described in detail. Figure 1 Examples of other core network nodes shown in include a gateway and a subscriber information repository.

[0034] The base station 130 has multiple beams 130A and 130B. Figure 1In the scenario shown, UE 110 is attached to beam 130A, and base station 135 has multiple beams 135A, 135B. The number of beams may exceed Figure 1 The number shown. Mobility events may include a switch from one beam to another beam of the same cell, or a switch from one cell to another cell. To support the mobility procedures, UEs including UE 110 are configured to make measurements to measure the signal strength of neighboring beams and / or cells, and report the results of these measurements to the network, which may then take decisions regarding mobility events such as beam changes or cell switches.

[0035] Such mobility measurements on the UE side are conventionally layer 3 measurements, and the corresponding reports are layer 3 or L3 reports. Similarly, handover commands from the network to the UE are usually layer 3 messages. Cell switching or beam changes directed using layer 3 commands involve resets of layers below layer 3, which can cause delays. Layer 3 is the radio resource control RRC layer in the technology standardized by the 3rd Generation Partnership Project 3GPP layer. Layer 1 or L1 in the lower layers in 3GPP technology is the physical layer, and layer 2 or L2 includes the media access control MAC layer, the radio link control RLC layer, and the packet data convergence protocol PDCP layer.

[0036] If mobility measurements indicate that the signal strength of the cell (or beam) to which the UE is currently attached is decreasing and the signal strength of another cell (or beam) is increasing, a switch to another cell (or beam) may be commanded by the network based on the mobility measurement report from the UE.

[0037] Signaling using the RRC protocol at the L3 layer involves latency, so it would be convenient to evaluate the impact of UE mobility on the signal strength of signals from different beams and cells at a lower layer such as the physical layer. Physical layer measurements can be made faster, and reports of such measurements using the physical layer directly instead of the L3 layer can be sent to the network faster. In some cases, physical layer reports are communicated using the L1 and L2 layers instead of the L3 layer. For example, in a distributed base station architecture, the centralized unit CU can act on layer 3 messages, while the distributed unit DU can act on the physical layer and layer 2 protocols. Therefore, information using layers 1 and 2 can be transmitted directly to the DU, enabling the DU to perform actions on the information.

[0038] In order to reduce the waiting time associated with layer 3 mobility events, L1 / L2 mobility enhancement can be configured in the system to implement the serving cell change via L1 / L2 signaling by reducing the overhead and interruption time associated with cell switching compared to the L3 process. For example, the network can configure the UE to start participating in the physical layer triggered mobility process in response to receiving a layer 3 mobility measurement report from the UE. In the physical layer triggered mobility process, the UE synchronizes with one or more candidate cells and sends a physical layer measurement report to the DU of the serving base station using L1 and L2. The UE can send the physical layer measurement report to the DU using L1 and L2 without using L3. The physical layer measurement report includes an indication of the candidate cell signal strength measured in the UE. The measurement can be performed on the physical layer, which means that the measurement does not involve the use of, for example, an L3 filter in the UE. Also in response to the layer 3 mobility measurement report, the serving base station can prepare the candidate cell for cell switching by providing the UE's context to the base station controlling the candidate cell. The UE context includes the information required to associate the UE with its active protocol connection, so it is provided to the candidate cell before the cell switch to speed up the cell switch process.

[0039] The DU of the serving base station may decide, based on the physical layer measurement report received from the UE, that the UE should acquire the timing advance of the candidate cell related to the physical layer measurement report. For example, this may be the case if it appears that the UE is turning to a cell switch to a candidate cell. The timing advance relates to the physical distance from the UE to the candidate cell base station along the radio path and is taken into account when communicating with the candidate cell base station to achieve the correct propagation time for the radio signal. This is useful because cellular technology uses radio frames and time slots, making it necessary for the signal to arrive at the base station in its appropriate time slot.

[0040] The timing advance may be obtained, for example, by the UE transmitting a random access preamble in a physical random access channel PRACH of the candidate cell. The candidate cell may then determine the timing advance value based on the timing information of the PRACH preamble received in the candidate cell, and the candidate cell may include the timing advance in a random access response RAR sent to the serving cell. Thus, the determined timing advance value may be provided to the UE by the serving cell, for example, in a MAC control element CE. Alternatively, the random access response itself may be provided to the UE, such that the UE can retrieve the timing advance value from the random access response.

[0041] Once the timing advance is acquired, the serving base station (e.g., the DU of the serving base station) can decide that a cell switch to the candidate cell is to be performed. This decision can be based on another physical layer measurement report from the UE, indicating that the signal strength of the candidate cell has continued to increase since the physical layer measurement report that prompted the acquisition of the timing advance of the candidate cell. If this is the case, the serving base station (e.g., its DU) can instruct the UE to switch to the candidate cell, and the UE can perform the switch by performing a random access procedure with the candidate cell. Knowing the timing advance in advance further speeds up the cell switch, because at this time the UE is already partially synchronized with the candidate cell and the random access procedure can be skipped.

[0042] However, acquiring the timing advance of the candidate cell causes a disruption in the communication between the UE and the serving cell. Uplink transmission to the serving cell requires the UE to suspend the time required to transmit the PRACH preamble to the candidate cell, and further, since the candidate cell may operate on a different frequency, the UE's transceiver will need to be retuned to the candidate cell frequency and then back to the serving cell frequency. In summary, if not much timing advance is acquired in advance before a single cell exchange, the timing gain from acquiring the timing advance before the cell exchange will outweigh the disruption caused by the acquisition of the timing advance. Therefore, it would be useful not to acquire the timing advance that is not ultimately used in the cell exchange.

[0043] Figure 2A is a coverage diagram of beams in a cellular communication system. This diagram is based on real measurements in a 3GPP fifth generation (5G) cellular communication system (in frequency range 2, i.e. 28 GHz), but the qualitative findings are also applicable to other systems. The distance between base stations in the diagram is 200 meters. In detail, as shown in Figure 2A As can be seen in Figure 1, the coverage can be uneven and include enclaves of beam coverage that are enclosed within the coverage area of ​​another beam or another cell. These enclaves are mainly caused by shadow fading and are more noticeable in frequency range 2 than in frequency range 1 due to the use of higher frequencies in frequency range 2. When a UE moves around in such an environment, it can easily happen that from the first physical layer measurement report of the candidate cell signal strength it appears that the UE is approaching a cell switch to a particular candidate cell, however a subsequent physical layer measurement report from the same UE may indicate that a cell switch to the particular candidate cell is no longer possible. While this is normal behavior, it presents a challenge in the physical layer triggered mobility process because in physical layer triggered mobility, the first physical layer measurement report may trigger the DU of the serving cell to request the UE to acquire the timing advance of a particular candidate cell. In the case where the subsequent physical layer measurement reports do not result in triggering a cell switch to the particular candidate cell, it is not necessary to acquire the timing advance and the associated connection interruption is unnecessary.

[0044] Figure 2B 2 is a coverage diagram of beams in a cellular communication system. Beam 210 and beam 220 are shown as their schematic coverage areas. Figure 2A This shows that in practice, the coverage area of ​​a beam or cell is larger than Figure 2B The moving trajectory 203 of the UE in the coverage area of ​​the beam 210 is Figure 2B 203 first approaches beam 220, but turns away and remains within the coverage area of ​​beam 210. Therefore, in the physical layer triggered mobility process, it can be seen based on the first physical layer measurement report that a cell switch to beam 220 will occur, but ultimately the cell switch does not occur. The timing advance of beam 220 may be unnecessarily acquired based on the first physical layer measurement report obtained when the UE moves along trajectory 203 towards beam 220.

[0045] In practice, if there is a road having the shape of trajectory 203, for example, in the coverage area of ​​beam 210, then trajectories such as trajectory 203 may be quite frequent or at least repeated. Another example is the case where a bus route or a tram or train track predictably carries several passengers along a route with turns at the same location. If the network can learn that the timing advance of beam 220 is not necessary when the UE moves along trajectory 203, the communication quality can be improved by avoiding connection interruptions associated with the acquisition of the timing advance of beam 220.

[0046] Figure 2C is a coverage diagram of beams in a cellular communication system. Here, the enclave covered by beam 240 is enclosed within the coverage area of ​​beam 230. Such an enclave is Figure 2A . Once again, the trajectory 205 of the UE has the behavior of approaching or even entering the coverage area of ​​another beam, however the cell switch to this cell does not occur and the acquisition of the timing advance of beam 240 is unnecessary and causes unnecessary service interruption for the UE traveling along the trajectory 205. This type of event can occur if, for example, a road or track crosses the enclave 240. If the network can learn that the acquisition of timing advance is not necessary for UEs crossing the trajectory 205, for example traveling along the road or track, the communication quality of these UEs can be improved, which is a clear beneficial technical effect.

[0047] In order for the network to be able to adapt its behavior to Figure 2B and Figure 2CIn order to take into account the coverage area effect shown in , the UE may be configured to transmit to the network a timing advance acquisition report including information about the acquisition of the timing advance value of the candidate cell. The UE may be configured to compile these reports and the data included therein as a response to at least one logging criterion being determined to be met in the UE. For example, these reports may be transmitted from the UE to the network periodically or during the connection process with Layer 3. The network may configure the compilation and transmission of these reports from the UE to the network, wherein the network may provide the UE with at least one logging criterion that triggers the addition of data to these reports. As an example, the network may transmit configuration information related to reporting a timing advance acquisition report, the configuration information including at least one logging criterion. The term "criterion" may be used in a context having the same meaning as "condition", "trigger condition" or "trigger information", etc.

[0048] Timing advance acquisition reports may be considered early timing advance acquisition reports because they include information describing the acquisition of timing advance for a candidate cell or cells during a physical layer triggered mobility procedure prior to issuing a cell switch command to the UE. In some cases, the timing advance is transmitted to the UE in a cell switch command, however the network then also acquires the timing advance before the cell switch command is sent to the UE, which also makes it an early timing advance. When sent to the network, the timing advance acquisition report may include information describing multiple acquisitions of timing advance values. For example, the timing advance acquisition report may include information describing multiple acquisitions of timing advance values ​​for the same cell. As another example, the timing advance acquisition report may include information describing multiple acquisitions of timing advance values ​​that have been recorded in the report during more than one physical layer triggered mobility procedure.

[0049] In particular, the at least one logging criterion may include at least one of the following: the base station instructs the candidate cell to acquire the timing advance for the first time, the base station instructs the candidate cell to acquire the timing advance for the second time, the base station instructs the candidate cell to acquire the timing advance for retransmission of the physical random access channel (PRACH) preamble, the base station instructs the second candidate cell to acquire the timing advance for the first time, the device receives the timing advance of the candidate cell via a random access response from the base station, the device receives the timing advance of the candidate cell via the media access control MAC control element CE during cell switching, and the UE receives a cell switching command from the base station via MAC CE.

[0050] Regarding the last logging criteria above, the UE may receive a timing advance in a MAC CE or via a random access response RAR before receiving a MAC CE carrying a cell switch command. If RAR is used, the serving base station may trigger a cell switch based on a random access channel RACH procedure to any cell, to a cell in which the UE has its timing advance or to a cell other than the cell in which the UE has its timing advance. In some cases, the serving base station does not indicate the RACH type and indicates a cell switch to any cell, to a cell in which the UE has its timing advance and thus performs a RACH-free cell switch, or to a cell other than the cell in which the UE has its timing advance, after which the UE performs a RACH-based cell switch. These alternatives may be used as logging criteria as specified by the serving base station.

[0051] Logging criteria may be defined to add data to the report when the UE receives a cell switch command from the serving base station via a MAC CE so that RAR is not used. In these cases, the UE may receive a timing advance in the MAC CE. In this case, logging is triggered when the MAC CE does not contain a timing advance but indicates a RACH-based cell switch. In addition, logging may be triggered in response to the following situations: the MAC CE does not contain a timing advance for the candidate cell and indicates a RACH-based cell switch, but 1) or 2) of the following situations: 1) before the MAC CE is received, the UE is triggered by the timing advance acquisition of the cell, and 2) before the MAC CE is received, the UE has transmitted a PRACH preamble to the candidate cell for early timing advance acquisition.

[0052] Further, logging may be triggered in the following cases: the UE receives a cell switch command from the serving base station via a MAC CE, such that the RAR is not configured, the MAC CE command does not contain a timing advance value of the candidate cell and indicates a RACH-based handover.

[0053] Furthermore, logging may be triggered in the following situations: the UE receives a cell switch command from the serving base station via a MAC CE, such that RAR is not configured, the MAC CE command does not contain the timing advance of the candidate cell and indicates a RACH-based switch, but is one of the following situations: 1) the UE is triggered by the timing advance acquisition of the cell before the MAC CE is received, and 2) the UE has transmitted a PRACH preamble to the candidate cell for early timing advance acquisition before the MAC CE is received.

[0054] Furthermore, logging may be triggered when the UE receives a cell switch command from the serving base station via a MAC CE, such that RAR is not configured, and the MAC CE command contains the TA of the target cell and indicates a no-RACH switch.

[0055] Furthermore, logging may be triggered when the UE receives a cell switch command from the serving base station via a MAC CE, such that RAR is not configured, and the MAC CE command contains the timing advance of the target cell and indicates no RACH switch, but 1) or 2) of the following situations: 1) before the MAC CE is received, the UE is triggered by the timing advance acquisition of another cell, and 2) before the MAC CE is received, the UE has sent a PRACH preamble to another candidate cell for early timing advance acquisition.

[0056] When the logging criteria are triggered and there is no existing TA acquisition report in the UE, the UE may initialize a new TA acquisition report and include therein the first data item of the newly initialized report.

[0057] Regarding the content of the timing advance acquisition reports, the UE may be configured to include at least one of the following in these reports: - Physical cell identity of the candidate cell, - the frequency of the candidate cell, - a first number indicating the number of times the device has been instructed to acquire the timing advance of a candidate cell, - a second number, indicating the number of times the device has transmitted a physical random access channel PRACH preamble code to the beam of the candidate cell to acquire a timing advance, - Multiple physical layer measurements of signal strength of candidate cells; - the random access preamble identifier and beam identifier that the device has used to transmit a PRACH preamble to the candidate cell to obtain a timing advance; - The geographical location together with the time of timing advance acquisition of the candidate cell; - an identification of the method used to acquire the timing advance of the candidate cell; - For the candidate cell, the number of times the timing advance acquisition is indicated, or -The number of retransmissions of the PRACH preamble used to obtain the timing advance of the candidate cell.

[0058] In some embodiments, the physical cell identifier of the candidate cell and the frequency of the candidate cell are included, and further, with respect to this cell, at least one of the following is included: 1) the number of times the UE is triggered by early timing advance for the cell and which beam it corresponds to, 2) for the acquisition of early timing advance for which beam, the number of times the UE has transmitted the PRACH preamble code, and 3) the UE has received an estimated timing advance from the serving base station via RAR or MAC CE.

[0059] When the UE sends a timing advance acquisition report to the network, the network or a self-organizing network function responsible for optimizing the timing advance acquisition process in the physical layer triggered mobility process can determine whether the UE has acquired the timing advance of the wrong cell and create a specific counter for the new cell pair, such as "unnecessary timing advance acquisition", which can be used for further statistical analysis. If the statistical analysis provides an indication that the timing advance acquisition is usually unnecessary for some cell neighbors, the network can initiate a readjustment of the parameters or trigger conditions in the base station, for example in the distributed unit of the base station, for the corresponding neighbor cell, if the problem is persistent on the cell boundary, then this will prevent the acquisition of the timing advance of the cell in at least some cases, which will enhance the suboptimal mobility performance towards the optimal level, because it will minimize the interruption experienced by the UE due to the wrong cell timing advance acquisition. Such a report can be reflected in the mobility robustness optimization MRO algorithm of the base station (such as DU) and can be used as an input to perform long-term optimization to achieve better handover decisions. In particular, in the case where the timing advance acquisition report includes information of the UE location, the network can discover specific locations where it is usually unnecessary to acquire the timing advance of a specific candidate cell. Therefore, the frequency with which such UEs are instructed to acquire timing advance may be reduced from an initial baseline level. The baseline level may be a default level that has not been adjusted based on TA acquisition reports.

[0060] As discussed previously in this document, cell switching can also be performed without timing advance, so if the network at a certain point suppresses the acquisition of a certain timing advance based on the timing advance acquisition report, and a cell change to that cell still occurs, the UE can perform a RACH procedure with that cell to complete the cell change.

[0061] Figure 3 An example apparatus capable of supporting at least some embodiments of the present invention is shown. Shown is a device 300, which may include, for example Figure 1UE 110 or, in applicable parts, base station 130. Included in device 300 is a processor 310, which may include, for example, a single-core or multi-core processor, wherein a single-core processor includes one processing core and a multi-core processor includes more than one processing core. Processor 310 may generally include a control device. Processor 310 may include more than one processor. When processor 310 includes more than one processor, device 300 may be a distributed device in which the processing of a task occurs in more than one physical unit. Processor 310 may be a control device. The processing core may include, for example, a Cortex-A8 processing core manufactured by ARM Holdings or a Zen processing core designed by Advanced Micro Devices Corporation. The processing core or processor may be or may include at least one qubit. Processor 310 may include at least one Qualcomm Snapdragon and / or Intel Atom processor. Processor 310 may include at least one application-specific integrated circuit (ASIC). Processor 310 may include at least one field programmable gate array (FPGA). Processor 310, optionally together with memory and computer instructions, may be means for performing method steps, such as processing, receiving, transmitting, sending, compiling, initializing, and determining, in device 300. Processor 310 may be configured, at least in part, by computer instructions to perform actions.

[0062] The processor may include, or be configured as, a circuit system or circuit systems that are configured to perform the stages of the method according to the embodiments described herein. As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware circuit implementation only, such as an implementation in analog and / or digital circuit systems only, and (b) a combination of hardware circuits and software, such as applicable to: (i) a combination of analog and / or digital hardware circuits and software / firmware, and (ii) any portion of (one or more) hardware processors with software (including one or more digital signal processors), software and (one or more) memories that work together to enable an apparatus such as a user equipment or base station to perform various functions and (c) one or more hardware circuits and / or one or more processors, such as one or more microprocessors or a portion of one or more microprocessors, that require software (e.g., firmware) for operation, but the software may not be present when not required for operation.

[0063] This definition of circuitry applies to all uses of the term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (their) accompanying software and / or firmware. For example, the term circuitry also covers a baseband integrated circuit or processor integrated circuit used in a mobile device or similar integrated circuit in a server, cellular network device, or other computing or network device, if applicable to the particular claim element.

[0064] Device 300 may include memory 320. Memory 320 may include random access memory and / or permanent memory. Memory 320 may include at least one RAM chip. Memory 320 may be a computer-readable medium. Memory 320 may include, for example, solid-state, magnetic, optical and / or holographic memory. Memory 320 may be at least partially accessible by processor 310. Memory 320 may be at least partially included in processor 310. Memory 320 may be a component for storing information. Memory 320 may include computer instructions that processor 310 is configured to execute. When computer instructions configured to cause processor 310 to perform certain actions are stored in memory 320, and device 300 as a whole is configured to run under the direction of processor 310 using computer instructions from memory 320, processor 310 and / or at least one of its processing cores may be considered to be configured to perform said certain actions. Memory 320 may be at least partially included in processor 310. Memory 320 may be at least partially external to device 300 but accessible to device 300. Memory 320 may be transient or non-transitory. As used herein, the term "non-transitory" is a limitation of the medium itself (ie, tangible rather than a signal), not a limitation on data storage persistence (eg, RAM vs. ROM).

[0065] Device 300 may include a transmitter 330. Device 300 may include a receiver 340. Transmitter 330 and receiver 340 may be configured to transmit and receive information, respectively, according to at least one cellular or non-cellular standard. Transmitter 330 may include more than one transmitter. Receiver 340 may include more than one receiver. Transmitter 330 and / or receiver 340 may be configured to operate, for example, according to Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (WCDMA), 5G, 6G, Long Term Evolution (LTE), IS-95, Wireless Local Area Network (WLAN), Ethernet, and / or Worldwide Interoperability for Microwave Access (WiMAX) standards.

[0066] Device 300 may include a near field communication (NFC) transceiver 350. NFC transceiver 350 may support at least one NFC technology, such as NFC, Bluetooth, Wibree, or similar technology.

[0067] Device 300 may include a user interface (UI) 360. UI 360 may include at least one of a display, a keyboard, a touch screen, a vibrator arranged to send a signal to the user by vibrating device 300, a speaker, or a microphone. The user is able to operate device 300 via UI 360, such as accepting an incoming phone call, establishing a phone call or video call, browsing the Internet, managing digital files stored in memory 320 or on a cloud accessible via transmitter 330 and receiver 340 or via NFC transceiver 350, and / or playing games.

[0068] The device 300 may include or be arranged to accept a user identity module 370. The user identity module 370 may include, for example, a subscriber identity module (SIM), a card installable in the device 300, or an embedded SIM (e-SIM). The user identity module 370 may include information identifying a subscription of a user of the device 300. The user identity module 370 may include cryptographic information that may be used to verify the identity of the user of the device 300 and / or facilitate encryption of communication information and billing of the user of the device 300 for communications implemented via the device 300.

[0069] The processor 310 may be equipped with a transmitter arranged to output information from the processor 310 to other devices included in the device 300 via electrical leads inside the apparatus 300. Such a transmitter may include a serial bus transmitter arranged to output information to the memory 320 for storage therein, for example, via at least one electrical lead. Alternatively to the serial bus, the transmitter may include a parallel bus transmitter. Likewise, the processor 310 may include a receiver arranged to receive information in the processor 310 from other devices included in the device 300 within the processor 310 via electrical leads inside the device 300. Such a receiver may include a serial bus receiver arranged to receive information, for example, via at least one electrical lead from a receiver 340 for processing in the processor 310. Alternatively to the serial bus, the receiver may include a parallel bus receiver.

[0070] The device 300 may include Figure 3Other devices not shown in the figure. For example, where the device 300 includes a smartphone, it may include at least one digital camera. Some devices 300 may include a rear camera and a front camera, wherein the rear camera may be intended for digital photography and the front camera is used for video telephony. The device 300 may include a fingerprint sensor arranged to at least partially authenticate a user of the device 300. In some embodiments, the device 300 lacks at least one of the above devices. For example, some devices 300 may lack an NFC transceiver 350 and / or a user identity module 370.

[0071] The processor 310, the memory 320, the transmitter 330, the receiver 340, the NFC transceiver 350, the UI 360 and / or the user identity module 370 can be interconnected in a variety of different ways through electrical leads inside the device 300. For example, each of the aforementioned devices can be connected to a main bus inside the device 300, respectively, to allow the devices to exchange information. However, as will be appreciated by those skilled in the art, this is only an example, and according to embodiments, various ways of interconnecting at least two of the aforementioned devices can be selected without departing from the scope of the present invention.

[0072] Figure 4 Signaling according to at least some embodiments of the present invention is shown. On the vertical axis, from the left are arranged UE, DU0 controlling the service cell, DU1 controlling cell 1, DU2 controlling cell 2, and service CU0. As an example, DU1 and DU2 may be connected to the same CU (e.g., CU0). Alternatively, DU1 and / or DU2 may be connected to a CU different from CU0. DU0 may be referred to as a service DU (or S-DU), DU1 and DU2 may be referred to as target DUs, referred to as target DU 1 and target DU 2, respectively. cell1 and cell2 may be target cells, which are some of the candidate cells. Time advances from top to bottom.

[0073] First, the UE sends a mobility measurement report to DU0 in stage 401, which is passed to the L3 layer of CU0 in stage 402. In response, in stage 403, CU0 decides to prepare cell 1 and cell 2 for receiving the UE. The preparation occurs in stages 404 and 405, and the UE context is provided to these cells by CU0, as described above. Further, the serving DU0 and CU0 configure the UE for a physical layer triggered mobility procedure with a timing advance acquisition report. In stage 406, a UE context modification procedure is implemented between DU0 and CU0. The configuration of the UE for the physical layer triggered mobility procedure involves CU0 generating an RRC reconfiguration in stage 407, which includes a measurement configuration for a physical layer cell change, a configuration of the prepared cell, and a timing advance acquisition report configuration. The timing advance acquisition report configuration may include or may indicate one or more logging criteria that trigger the UE to include data in the timing advance acquisition report. The data that the UE may include in the report has been discussed above, in particular, the data may include information about timing advance acquisition (eg, timing advance acquisition that does not result in a cell change).

[0074] In stage 408, CU0 provides an RRC message to DU0, which includes a timing advance acquisition criterion, a cell exchange criterion, and a timing advance acquisition report configuration. The timing advance acquisition report configuration may include an early timing advance acquisition report configuration. DU0 provides an RRC reconfiguration message to the UE in stage 409, which includes a timing advance acquisition report configuration and a timing advance acquisition criterion.

[0075] Additionally or alternatively, the early timing advance acquisition report configuration may be transparently sent by DU0 at stage 408 .

[0076] In stage 410, the UE confirms receipt of the configuration it has received to DU0, for example in an RRC Reconfiguration Complete message. DU0 forwards this information to CU0 in stage 412, for example as an uplink RRC messaging message. In stage 414, the UE may perform L1 layer measurements based on the measurement configuration and the early TA acquisition configuration. The UE then transmits a physical layer measurement report of the signal strength of a candidate cell, for example, cell 1, to DU0.

[0077] In response, in stage 416, DU0 may determine a TA acquisition condition based on at least one of an early TA acquisition configuration or a physical layer measurement report. Once the condition is met, DU0 determines a timing advance that instructs the UE to acquire at least one candidate cell (e.g., cell 1 and / or cell 2). DU0 transmits an instruction to the UE to acquire (multiple) TAs in stage 417.

[0078] Stage 418 represents a determination in the UE that the possible logging criteria are satisfied, since the timing advance acquisition instruction for cell 1 is received for the first time. To acquire the timing advance for cell 1, the UE transmits a PRACH preamble to DU1 in stage 420. In stage 424, the PRACH preamble triggers DU1 (i.e., cell 1) to transmit a RAR message including the timing advance to CU0. CU0 then forwards the RAR to DU0 in stage 426. The RAR may be further forwarded from DU0 to the UE.

[0079] Additionally or alternatively, for the exemplary embodiment, stage 422 is a second possible log trigger satisfaction at the UE. The UE may be configured to generate an early TA acquisition report after transmission of the PRACH preamble and then transmit the early TA acquisition report to the S-DU (ie, DU0).

[0080] In phase 428, the UE may perform measurement of candidate cell signal strength associated with cell 2 and send a second physical layer measurement report of the candidate cell signal strength.

[0081] DU0 responsively decides in stage 430 that the UE will acquire the timing advance of cell 2. DU0 instructs the UE to do so in stage 432. Stage 434 represents a determination in the UE that another possible logging criterion is satisfied, since the timing advance acquisition instruction for cell 2 is received for the first time.

[0082] To acquire the timing advance of cell 2, the UE transmits a PRACH preamble to DU2 in stage 436. In stage 438, the PRACH preamble triggers DU2 (i.e., cell2) to transmit a RAR message including the timing advance to CU0. CU0 then forwards the RAR to DU0 in stage 440. The RAR may be further forwarded from DU0 to the UE. DU0 may provide the RAR or its timing advance information to the UE, for example, in a MAC CE.

[0083] Additionally or alternatively, for the exemplary embodiments, in stage 435, the UE may be configured to generate an early TA acquisition report after transmitting the PRACH preamble to cell 2, and then transmit the early TA acquisition report to the S-DU (ie, DU0).

[0084] In stage 442 , the UE may perform L1 layer or L2 measurement of the candidate cell signal strength of cell 2 , and then the UE transmits a physical layer measurement report containing the L1 or L2 measurement on cell 2 to DU0 .

[0085] In response, in stage 444, DU0 decides to initiate a cell switch of the UE to cell 2 based on the physical layer measurement reports in stage 428 and / or stage 436. Then, in stage 446, DU0 transmits a MAC CE to the UE to trigger a cell change to cell 2. The MAC CE may include a timing advance of cell 2 for the UE, especially if the RAR of stage 440 is not forwarded to the UE earlier. In stage 448, a random access procedure occurs, or if the UE has a timing advance of cell 2, a RACH-free cell switch may occur. In a RACH-free cell switch, the UE may send an RRC message directly to the target cell, saving time that would otherwise be used for a RACH procedure.

[0086] In stage 450, in some embodiments, the UE may decide to indicate the availability of the TA acquisition report that has been generated in the previous step. In other embodiments, the UE may decide to indicate the availability of the TA acquisition report only if the TA acquisition is triggered more than once by the S-DU / serving cell. In further embodiments, the UE may decide to indicate the availability of the TA acquisition report only if the TA acquisition is triggered more than once by the S-DU / serving cell for two or more different cells.

[0087] In stage 452, an RRC Reconfiguration Complete message is provided from UE2 to DU2 to inform the network of the successful completion of the RRC reconfiguration applied for handover to Cell 2. The message may include an indication that the UE has a timing advance acquisition report that may be provided to the network.

[0088] In stage 454, DU2 indicates to CU0 that the cell switch is complete and further that the UE has a timing advance acquisition report ready for provision. In other words, DU2 may forward the UE's RRC reconfiguration complete message to the CU, which may contain an indication of the availability of an early TA acquisition report at the UE. For example, the message of stage 454 may be an uplink RRC messaging message.

[0089] Stage 456 includes the original serving cell DU0 (which controls cell 0) requesting an early TA acquisition report via DU2.

[0090] In stage 458, the Early TA Acquisition Report is provided from the UE to CU0 via DU2. The Early TA Acquisition Report may then be used by DU0 to decide whether to instruct other UEs to acquire the timing advance of candidate cells in a physical layer triggered mobility procedure.

[0091] In some embodiments, the UE is configured to receive the RAR directly from the candidate cell. In this case, the UE can obtain the timing advance of the candidate cell from the RAR, and the DU of the serving base station does not need to include it in the MAC CE that commands the UE to perform cell switching.

[0092] Figure 5 is a flow chart of a method according to at least some embodiments of the present invention. The method may be performed in a DU, such as a base station, or in a control device configured to control functions of the DU when installed therein.

[0093] Processing starts in stage 510, where a timing advance acquisition report is received in the DU. Here, the source cell of the mobility procedure triggered by the physical layer is cell X. Processing proceeds to stage 520, where it is determined whether the UE has already acquired the timing advance of cell Y. If this is the case, processing proceeds to stage 530, where it is determined whether the UE changes cells to cell Y. If this is the case, processing proceeds to stage 540, where the decision probability of instructing the UE in cell X to acquire the timing advance of cell Y remains unchanged. On the other hand, if it is determined in stage 520 that the UE has not acquired the timing advance of cell Y, the process proceeds directly from stage 520 to stage 540. If it is determined in stage 530 that the UE has not changed cells to cell Y, the process proceeds to stage 550, where the probability of the UE in cell X being instructed to acquire the timing advance of cell Y is reduced by, for example, 5% or 10%.

[0094] Figure 6 is a flow chart of a method according to at least some embodiments of the present invention. The stages of the method shown may be performed in the UE 110, or in a control device configured to control its functions when installed therein.

[0095] Stage 610 includes receiving configuration information related to reporting early timing advance (TA) acquisition. Stage 620 includes receiving at least one instruction to acquire at least one TA value for at least one candidate cell. Stage 630 includes generating an early timing advance acquisition report based on the at least one TA value and based on the configuration information. Finally, stage 640 includes transmitting an indication indicating the availability of an early TA acquisition report. The indication indicating the availability of an early TA acquisition report may indicate that an apparatus (such as a UE) performing the method has an early TA acquisition report that it can send.

[0096] In some embodiments, the method comprises, in response to at least one logging criterion being satisfied, including in a TA acquisition report information regarding the acquisition of at least one timing advance value for at least one candidate cell.

[0097] In some embodiments, the method includes obtaining at least one logging criterion from configuration information related to reporting early TA acquisition.

[0098] In some embodiments, the method comprises transmitting a physical layer measurement report on the physical layer and the radio link layer in the uplink direction.

[0099] In some embodiments, the method includes compiling a physical layer measurement report by measuring candidate cell signal strengths on a physical layer.

[0100] In some embodiments, the method includes initiating an early TA acquisition report in response to determining that one or more timing advances that did not result in a cell switch were acquired.

[0101] In some embodiments, the method includes providing an early TA acquisition report to a network, the device being served by the network.

[0102] In some embodiments, at least one logging criterion includes at least one of the following: first reception of an instruction for early TA acquisition of at least one candidate cell, second reception of an instruction for early TA acquisition of at least one candidate cell, reception of an indication for early TA acquisition of at least one candidate cell for retransmission of a physical random access channel PRACH preamble, first reception of an instruction for early TA acquisition of a second candidate cell, reception of early TA acquisition of at least one candidate cell via a random access response, reception of early TA acquisition of at least one candidate cell via a media access control MAC control element CE during cell exchange, or reception of a cell exchange command via the MAC CE.

[0103] In some embodiments, the method includes including at least one of the following in the early TA acquisition report: a physical cell identifier of the candidate cell, a frequency of the candidate cell, a first number indicating the number of times the device has been instructed to acquire a TA value for at least one candidate cell, a second number indicating the number of times the device has transmitted a physical random access channel (PRACH) preamble to a beam of at least one candidate cell to acquire a TA value, one or more of physical layer measurement results of a signal strength of at least one candidate cell, a random access preamble identifier and a beam identifier that the device has used to transmit a PRACH preamble to at least one candidate cell to acquire a TA value, a geographic location together with a time of TA acquisition for at least one candidate cell, an identifier of a method used to acquire a TA value for at least one candidate cell, and for at least one candidate cell, the number of times early TA acquisition has been indicated, or the number of retransmissions of a PRACH preamble, to acquire a TA value for at least one candidate cell.

[0104] Figure 7is a flow chart of a method according to at least some embodiments of the present invention. The stages of the method shown may be performed in a DU or in a control device configured to control its functions when installed therein.

[0105] Stage 710 includes receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration. Stage 720 includes providing configuration information related to reporting early TA acquisition to the user equipment, wherein the configuration information includes at least one of the TA acquisition criterion or the timing advance acquisition report configuration. Stage 730 includes determining whether a TA acquisition condition is satisfied based on the configuration information. Stage 740 includes sending at least one instruction to the user equipment to acquire at least one TA value of at least one candidate cell.

[0106] In some embodiments, the method includes further performing a determination whether a TA acquisition condition is satisfied based on a plurality of early timing advance acquisition reports.

[0107] In some embodiments, the method includes: as an early timing advance acquisition report indicating that the timing advance value of the specific candidate cell has been repeatedly acquired by multiple user equipments so that cell switching has not occurred, determining to send an instruction to another user equipment to acquire the timing advance value of the specific candidate cell less frequently than the baseline.

[0108] In some embodiments, the method includes performing a determination to send an instruction to another user equipment to acquire a timing advance value for a particular candidate cell less frequently than a baseline only when the other user equipment is in a geographic area, wherein the early timing advance acquisition report indicates that the geographic area is associated with multiple acquisitions of the timing advance value such that no cell exchange occurs.

[0109] In some embodiments, the method comprises receiving from the user equipment a physical layer measurement report of the candidate cell signal strength as measured by the first user equipment.

[0110] In some embodiments, the method comprises: determining to instruct the user equipment to change its serving cell based at least in part on a second physical layer measurement report received in the apparatus from the user equipment, and instructing the user equipment to change its serving cell.

[0111] Figure 8 is a flow chart of a method according to at least some embodiments of the present invention. The stages of the method shown may be performed in a CU, or in a control device configured to control its functions when installed therein.

[0112] Stage 810 comprises preparing at least one target cell associated with a user equipment served by a base station, the apparatus being comprised by the base station. Stage 820 comprises generating configuration information comprising at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration. Stage 830 comprises providing the configuration information to a distributed unit of the base station.

[0113] In some embodiments, the method comprises receiving an indication that the user equipment has an early TA acquisition report.

[0114] In some embodiments, the method comprises requesting an early TA acquisition report from the user equipment via one of the at least one target cell, and receiving the early TA acquisition report from the user equipment.

[0115] In some embodiments of the present invention, an apparatus is provided, comprising at least one processing core and at least one memory storing instructions, the instructions, when executed by the at least one processing core, causing the apparatus to at least: when the apparatus is installed in a user equipment, control a function of the user equipment; receive configuration information related to reporting early timing advance TA acquisition via a transceiver of the user equipment; receive at least one instruction to acquire at least one TA value of at least one candidate cell via a transceiver of the user equipment; generate an early timing advance acquisition report based on the at least one TA value and based on the configuration information; and instruct the transceiver of the user equipment to transmit an indication indicating the availability of the early TA acquisition report. For example, the apparatus may be a chipset configured to control a UE.

[0116] It should be understood that the disclosed embodiments of the present invention are not limited to the specific structures, process steps or materials disclosed herein, but are extended to their equivalents as recognized by those of ordinary skill in the relevant art. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not intended to be limiting.

[0117] References throughout this specification to an embodiment or an embodiment mean that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the invention. Thus, the phrases "in one embodiment" or "in an embodiment" appearing throughout this specification do not necessarily all refer to the same embodiment. Where reference is made to a value using terms such as, for example, approximately or substantially, the exact value is also disclosed.

[0118] As used herein, for convenience, multiple projects, structural elements, constituent elements and / or materials can be presented in a public list. However, these lists should be understood as each member of the list being separately identified as separate and unique members. Therefore, the individual members of such lists should not be understood as the de facto equivalents of any other members of the same list simply based on their presentation in the public group without opposite instructions. Additionally, various embodiments of the present invention and examples are referred to together with alternatives for its various components herein. It should be understood that such embodiments, examples and alternatives should not be understood as de facto equivalents to each other, but are considered to be separated and autonomous representations of the present invention.

[0119] In addition, in one or more embodiments, the described features, structures or characteristics may be combined in any suitable manner. In the foregoing description, many specific details are provided, such as examples of length, width, shape, etc., to provide a thorough understanding of embodiments of the present invention. However, those skilled in the relevant art will recognize that the present invention may be practiced without one or more of the specific details, or may be practiced using other methods, components, materials, etc. In other examples, well-known structures, materials, or operations are not represented or described in detail to avoid obscuring aspects of the present invention.

[0120] Although the foregoing examples illustrate the principles of the present invention in one or more specific applications, it is apparent to those skilled in the art that many modifications of form, use, and implementation details may be made without using innovative capabilities and without departing from the principles and concepts of the present invention. Therefore, it is not intended that the present invention be limited except as set forth below in the claims.

[0121] The verbs "comprise" and "include" are used in this document as open limitations that neither exclude nor require the existence of unrecited features. Unless explicitly stated otherwise, the features recited in the dependent claims may be freely combined with each other. Furthermore, it will be understood that the use of "a" (i.e., the singular) throughout this document does not exclude a plurality.

[0122] As used herein, “at least one of: ” and “at least one of ” and similar expressions, where a list of two or more elements is connected by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all of the elements. Industrial Applicability

[0123] At least some embodiments of the present invention find industrial application in cellular networks. List of abbreviations 3GPP Third Generation Partnership Project CEM Control Element CU Centralized Unit DU Distributed Unit MAC Media Access Control PDCP Packet Data Convergence Protocol RAR Random Access Response RRC Radio Resource Control PRACH Physical Random Access Channel RLC Radio Link Control TA Timing Advance Reference Symbols List Example 1. An apparatus comprising at least one processing core and at least one memory storing instructions that, when executed by the at least one processing core, cause the apparatus to at least: - Receive configuration information related to TA acquisition in advance of reporting timing; - receiving at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Transmitting an indication indicating the availability of an early TA acquisition report. Example 2. An apparatus comprising at least one processing core and at least one memory storing instructions, which, when executed by the at least one processing core, cause the apparatus to at least: - receiving, via a transceiver of the user equipment, configuration information related to the acquisition of the reporting early timing advance TA; - receiving, via a transceiver of a user equipment, at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Instructing the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report. Example 3. The apparatus of example 1 or 2, configured to include information on acquisition of at least one timing advance value for at least one candidate cell in a TA acquisition report in response to at least one logging criterion being met. Example 4 The apparatus of Example 3, further configured to obtain at least one logging criterion from configuration information related to reporting early TA acquisition. Example 5. An apparatus according to any one of Examples 1 to 4, wherein the apparatus is configured to transmit physical layer measurement reports on the physical layer and the radio link layer in an uplink direction. Example 6. The apparatus of Example 5, wherein the apparatus is configured to compile a physical layer measurement report by measuring candidate cell signal strength on a physical layer. Example 7. The apparatus of any one of Examples 1 to 6, wherein the apparatus is configured to initialize an early TA acquisition report in response to determining that one or more timing advances that did not result in a cell switch were acquired. Example 8. The apparatus of any one of Examples 1 to 7, configured to provide an early TA acquisition report to a network, the apparatus being served by the network. Example 9. The apparatus of any of Examples 3-8, wherein at least one logging criterion comprises at least one of the following: Receipt of a first instruction for early TA acquisition of at least one candidate cell; receiving a second instruction for early TA acquisition of at least one candidate cell; Receipt of an instruction for early TA acquisition of at least one candidate cell for retransmission of a physical random access channel PRACH preamble; Receiving a first instruction for early TA acquisition of a second candidate cell; reception of early TA acquisition of at least one candidate cell via a random access response; reception of early TA acquisition of at least one candidate cell via a medium access control MAC control element CE during cell switching; Reception of a cell switch command via MAC CE. Example 10. The apparatus of any one of Examples 1-8, configured to include at least one of the following in the early TA acquisition report: The physical cell identifier of the candidate cell; The frequency of the candidate cells; A first number indicating the number of times the apparatus has been instructed to obtain a TA value of at least one candidate cell; a second number indicating the number of times the apparatus has transmitted a physical random access channel PRACH preamble code to a beam of at least one candidate cell to obtain a TA value; one or more of physical layer measurements of signal strength of at least one candidate cell; The apparatus has been used to transmit a PRACH preamble to at least one candidate cell to obtain a random access preamble identifier and a beam identifier of a TA value; the geographical location together with the time of TA acquisition of at least one candidate cell; an identification of a method for obtaining a TA value of at least one candidate cell; For at least one candidate cell, the number of times the TA is instructed to obtain in advance; The number of PRACH preamble retransmissions is used to obtain the TA value of at least one candidate cell. Example 11. An apparatus comprising at least one processing core and at least one memory storing instructions that, when executed by the at least one processing core, cause the apparatus to at least: - receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration; -Providing configuration information related to reporting early TA acquisition to the user equipment, wherein the configuration information includes at least one of a TA acquisition criterion or a timing early acquisition report configuration; -Based on the configuration information, determine whether the TA acquisition condition is met; - sending at least one instruction to the user equipment to obtain at least one TA value of at least one candidate cell. Example 12. The apparatus of Example 11, wherein the apparatus is configured to further perform the determination of whether the TA acquisition condition is satisfied based on a plurality of early timing advance acquisition reports. Example 13. An apparatus according to Example 12, wherein the apparatus is configured to determine, in response to an early timing advance acquisition report indicating that the timing advance value of a specific candidate cell has been repeatedly acquired by multiple user equipments so that no cell exchange occurs, to send an instruction to another user equipment to acquire the timing advance value of the specific candidate cell less frequently than a baseline. Example 14. An apparatus according to Example 13, wherein the apparatus is configured to: when another user equipment is in the following geographic area, only determine to send an instruction to the other user equipment to obtain the timing advance value of a specific candidate cell less frequently than the baseline, and an early timing advance acquisition report indicates that the geographic area is associated with multiple acquisitions of the timing advance value so that no cell exchange occurs. Example 15 The apparatus according to any one of Examples 11 to 14, further configured to receive a physical layer measurement report of the candidate cell signal strength as measured by the first user equipment from the user equipment. Example 16. The apparatus according to any one of Examples 11 to 15 is further configured to determine, at least in part based on a second physical layer measurement report received in the apparatus from the user equipment, to instruct the user equipment to change its serving cell, and to instruct the user equipment to change its serving cell. Example 17. An apparatus comprising at least one processing core and at least one memory storing instructions that, when executed by the at least one processing core, cause the apparatus to at least: - preparing at least one target cell associated with a user equipment served by the base station, the device being included in the base station; - generating configuration information, the configuration information including at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration; -Provide configuration information to the distributed units of the base station. Example 18. The apparatus of Example 17, further configured to receive an indication that the user equipment has an early TA acquisition report. Example 19. The apparatus according to Example 18, wherein the apparatus is configured to request an early TA acquisition report from the user equipment via one of the at least one target cell, and receive the early TA acquisition report from the user equipment. Example 20. A method comprising: - receiving configuration information related to reporting early timing advance TA; - receiving at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Transmitting an indication indicating the availability of an early TA acquisition report. Example 21. A method comprising: - receiving, via a transceiver of the user equipment, configuration information related to the acquisition of the reporting early timing advance TA; - receiving, via a transceiver of a user equipment, at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Instructing the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report. Example 22. The method of Example 20 or 21, comprising, in response to at least one logging criterion being satisfied, including information regarding acquisition of at least one timing advance value for at least one candidate cell in the TA acquisition report. Example 23. The method of Example 22, further comprising obtaining at least one logging criterion from configuration information related to reporting early TA acquisition. Example 24. A method according to any one of Examples 20 to 23, wherein the method includes transmitting a physical layer measurement report on the physical layer and the radio link layer in an uplink direction. Example 25. The method of Example 24, comprising compiling a physical layer measurement report by measuring candidate cell signal strength on a physical layer. Example 26. The method of any one of Examples 20 to 25, wherein the method comprises: in response to determining that one or more timing advances that did not result in a cell switch were acquired, initializing an early TA acquisition report. Example 27. The method of any one of Examples 20 to 26, comprising providing an early TA acquisition report to a network, the apparatus being served by the network. Example 28. The method of any of Examples 22 to 27, wherein at least one logging criterion comprises at least one of the following: Receipt of a first instruction for early TA acquisition of at least one candidate cell; receiving a second instruction for early TA acquisition of at least one candidate cell; Receipt of an instruction for early TA acquisition of at least one candidate cell for retransmission of a physical random access channel (PRACH) preamble; Receiving a first instruction for early TA acquisition of a second candidate cell; reception of early TA acquisition of at least one candidate cell via a random access response; Early TA acquisition of at least one candidate cell via a medium access control (MAC) control element (CE) during cell switching; Reception of a cell switch command via MAC CE. Example 29. The method of any one of Examples 20 to 28, comprising including at least one of the following in the early TA acquisition report: The physical cell identifier of the candidate cell; The frequency of the candidate cells; a first number indicating a number of times the apparatus has been instructed to obtain a TA value of at least one candidate cell; a second number indicating the number of times the apparatus has transmitted a physical random access channel PRACH preamble code to a beam of at least one candidate cell to obtain a TA value; one or more of physical layer measurements of signal strength of at least one candidate cell; The apparatus has been used to transmit a PRACH preamble to at least one candidate cell to obtain a random access preamble identifier and a beam identifier of a TA value; a geographical location together with a time at which a TA value of at least one candidate cell is obtained; an identification of a method for obtaining an early TA value of at least one candidate cell; For at least one candidate cell, the number of times early TA acquisition is indicated; The number of retransmissions of the PRACH preamble code is used to obtain the TA value of at least one candidate cell. Example 30. A method comprising: - receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration; -Providing configuration information related to reporting early TA acquisition to the user equipment, wherein the configuration information includes at least one of a TA acquisition criterion or a timing early acquisition report configuration; -Based on the configuration information, determine whether the TA acquisition condition is met; - sending at least one instruction to the user equipment to obtain at least one TA value of at least one candidate cell. Example 31. The method of Example 30, wherein the method comprises further performing the determination of whether the TA acquisition condition is satisfied based on a plurality of early timing advance acquisition reports. Example 32. A method according to Example 31, wherein the method includes determining, in response to an early timing advance acquisition report indicating that the timing advance value of a specific candidate cell has been repeatedly acquired by multiple user equipments so that no cell exchange occurs, to send an instruction to another user equipment to acquire the timing advance value of the specific candidate cell less frequently than a baseline. Example 33. A method according to Example 32, wherein the method includes performing a determination to send an instruction to another user equipment to acquire a timing advance value for a particular candidate cell less frequently than a baseline only when the other user equipment is in the following geographic area, and an early timing advance acquisition report indicates that the geographic area is associated with multiple acquisitions of timing advance values ​​so that no cell exchange occurs. Example 34. The method of any one of Examples 30 to 33, further comprising receiving, from the user equipment, a physical layer measurement report of the candidate cell signal strength as measured by the first user equipment. Example 35. The method according to any one of Examples 30 to 34 further includes determining to instruct the user equipment to change its serving cell based at least in part on a second physical layer measurement report received from the user equipment in the device, and instructing the user equipment to change its serving cell. Example 36. A method comprising: - preparing at least one target cell associated with a user equipment served by the base station, the device being included in the base station; - generating configuration information, the configuration information including at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration; -Provide configuration information to the distributed units of the base station. Example 37. The method of Example 36, further comprising receiving an indication that the user equipment has an early TA acquisition report. Example 38. The method of Example 37, wherein the method comprises: requesting an early TA acquisition report from the user equipment via one of the at least one target cell, and receiving the early TA acquisition report from the user equipment. Example 39. A non-transitory computer-readable medium having stored thereon a set of computer-readable instructions that, when executed by at least one processor, cause the apparatus to at least: - receiving configuration information related to reporting early timing advance TA; - receiving at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Transmitting an indication indicating the availability of an early TA acquisition report. Example 40. A non-transitory computer-readable medium having stored thereon a set of computer-readable instructions that, when executed by at least one processor, cause the apparatus to at least: - receiving, via a transceiver of a user equipment, configuration information related to reporting an early timing advance (TA); - receiving, via a transceiver of a user equipment, at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on at least one TA value and based on the configuration information; - Instructing the transceiver of the user equipment to transmit an indication indicating the availability of an early TA acquisition report. Example 41. A non-transitory computer readable medium having stored thereon a set of computer readable instructions that, when executed by at least one processor, cause the apparatus to at least: - receiving at least one timing advance TA acquisition criterion and an early timing advance acquisition report configuration; -Providing configuration information related to reporting early TA acquisition to the user equipment, wherein the configuration information includes at least one of a TA acquisition criterion or a timing early acquisition report configuration; -Based on the configuration information, determine whether the TA acquisition condition is met; - sending at least one instruction to the user equipment to obtain at least one TA value of at least one candidate cell. Example 42. A non-transitory computer-readable medium having stored thereon a set of computer-readable instructions that, when executed by at least one processor, cause the apparatus to at least: - preparing at least one target cell associated with a user equipment served by the base station, the device being included in the base station; - generating configuration information, the configuration information including at least one of a timing advance TA acquisition criterion and a TA acquisition report configuration; -Provide configuration information to the distributed units of the base station.

Claims

1. An apparatus for communication, comprising at least one processing core and at least one memory storing instructions, wherein the instructions, when executed by the at least one processing core, cause the apparatus to at least: - Receive configuration information related to TA acquisition in advance of reporting timing; - receiving at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on the at least one TA value and based on the configuration information; - transmitting an indication indicating the availability of said early TA acquisition report.

2. An apparatus for communication, comprising at least one processing core and at least one memory storing instructions, wherein the instructions, when executed by the at least one processing core, cause the apparatus to at least: - receiving, via a transceiver of the user equipment, configuration information related to the acquisition of the reporting early timing advance TA; - receiving, via the transceiver of the user equipment, at least one instruction to obtain at least one TA value of at least one candidate cell; - generating an early timing advance acquisition report based on the at least one TA value and based on the configuration information; - instructing the transceiver of the user equipment to transmit an indication indicating the availability of the early TA acquisition report.

3. The apparatus according to claim 1 or 2, configured to include, in the TA acquisition report, the acquired information about the at least one timing advance value of the at least one candidate cell in response to at least one logging criterion being met. 4 . The apparatus of claim 3 , further configured to obtain the at least one logging criterion from the configuration information related to reporting the early TA acquisition.

5. The apparatus according to any one of claims 1 to 4, wherein the apparatus is configured to transmit physical layer measurement reports on the physical layer and the radio link layer in an uplink direction. 6 . The apparatus of claim 5 , wherein the apparatus is configured to compile the physical layer measurement report by measuring candidate cell signal strength on the physical layer.

7. The apparatus according to any one of claims 1 to 6, wherein the apparatus is configured to initialize the early TA acquisition report in response to determining that one or more timing advances that did not result in a cell switch were acquired.

8. The apparatus according to any one of claims 1 to 7, configured to provide the early TA acquisition report to a network, the apparatus being served by the network.

9. The apparatus according to any one of claims 3 to 8, wherein the at least one logging criterion comprises at least one of the following: receiving, for the first time, an instruction for early TA acquisition of the at least one candidate cell; receiving, for a second time, the instruction for early TA acquisition of the at least one candidate cell; receiving the instruction of early TA acquisition of the at least one candidate cell for retransmission of a physical random access channel PRACH preamble; receiving, for the first time, the instruction for early TA acquisition of the second candidate cell; receiving, via a random access response, the early TA acquisition of the at least one candidate cell; receiving, via a medium access control MAC control element CE, said early TA acquisition of said at least one candidate cell during a cell switch; Reception of a cell switch command via MAC CE.

10. The apparatus according to any one of claims 1 to 8, configured to include at least one of the following in the early TA acquisition report: A physical cell identifier of the candidate cell; The frequency of the candidate cell; a first number indicating a number of times the apparatus has been instructed to obtain a TA value for the at least one candidate cell; a second number indicating a number of times the apparatus has transmitted a physical random access channel PRACH preamble code to a beam of the at least one candidate cell to obtain a TA value; one or more of the physical layer measurement results of the signal strength of the at least one candidate cell; The apparatus has been used to transmit a PRACH preamble to the at least one candidate cell to obtain a random access preamble identifier and a beam identifier of a TA value; a geographical location together with a time of TA acquisition of the at least one candidate cell; an identification of a method for obtaining a TA value of the at least one candidate cell; for the at least one candidate cell, the number of times the early TA acquisition is instructed; The number of PRACH preamble code retransmissions is used to obtain the TA value of the at least one candidate cell.

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