CN115150878A

CN115150878A - Random access information reporting method and user equipment

Info

Publication number: CN115150878A
Application number: CN202110343913.3A
Authority: CN
Inventors: 常宁娟; 刘仁茂
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 2021-03-30
Filing date: 2021-03-30
Publication date: 2022-10-04
Also published as: WO2022206668A1

Abstract

The disclosure provides a random access information reporting method and user equipment. The method for reporting the random access information executed by the user equipment comprises the following steps: initiating and completing a small data transmission SDT process; and sending, to a network side, an RA information report containing information indicating downlink quality information obtained by the UE immediately before initiation of the SDT procedure in relation to the SDT procedure. Therefore, a more refined RA report in the SCG activation scene can be realized, and the RACH performance or the SDT transmission performance can be improved.

Description

Random access information reporting method and user equipment

Technical Field

The present disclosure relates to the field of wireless communication technologies, and in particular, to a random access information reporting method performed by a user equipment and a corresponding user equipment.

Background

The aim of optimizing the network performance can be achieved through network optimization in the wireless network. Generally, means such as data acquisition and data analysis are performed on an existing deployed and operated network, so that the reason influencing the network quality is found out, and the network performance is improved by means such as modifying configured network parameters, adjusting a network structure and deployed equipment. For Self-configuring and Self-optimizing networks (SON), it refers to a process of automatically adjusting the Network based on measurements/performance measurements of user equipment and/or base stations. The network side may configure the UE to perform measurements for SON. The SON Function includes many aspects, such as an Automatic neighbor Relation Function (ANR) for reducing the neighbor management burden of an operator, a Mobility Load Balancing Function (MLB) for Balancing responsibility among different cells, a Mobility Robustness Optimization (MRO) Function for optimizing Mobility performance, a random access channel Optimization Function for optimizing random access channel parameters, and a radio link failure reporting Function for optimizing coverage and MRO, etc.

The third Generation Partnership project (3 rd Generation Partnership project:3 gpp) RAN congress approved a New work project of release 17 for further enhancements to New Radio technology (NR, new Radio) (see RP-201281. One of the objectives of its research project is to further enhance and implement SON functions for NR systems of release 16 and previous releases, including mobile robustness optimization under new handover mechanism, random access channel performance, etc.

Furthermore, another release 17 research project (see 3GPP document RP-193252 (Work Item on NR Small Data transmissions in INACTIVE state)) is currently being conducted by the 3GPP RAN2 working group, referred to as the Small Data Transmission (SDT) project. The purpose of this research project is to optimize for the signaling overhead and power consumption resulting from small-size data traffic that is infrequently transmitted by users. For a User Equipment (UE) in a Radio Resource Control Inactive state (RRC _ Inactive), some infrequent small-size data services (such as instant information, heartbeat signals kept online, cycle information of an intelligent wearable device or a sensor, and a periodic table reading service brought by an intelligent metering device) are transmitted so that the UE needs to enter a Radio Resource Control CONNECTED state RRC _ CONNECTED to perform transmission of a small-size data packet, and thus signaling overhead brings about reduction of network performance and also greatly consumes energy consumption of the UE. In the currently studied SDT mechanism, one way is to carry small-size data in the random access procedure (e.g., small data carried in message 3 accompanying or included in the four-step random access procedure or small data carried in message a accompanying or included in the two-step random access procedure), and transmit data through a UE dedicated channel (e.g., dedicated traffic channel DTCH or dedicated control channel DCCH) after the random access procedure, but without entering the RRC _ CONNECTED state to acquire uplink transmission resources, so as to achieve the purpose of reducing signaling overhead and UE energy consumption.

The disclosure aims to realize the problem of reporting random access information in an SON function in an NR network, and further, solves the problem of how to more accurately feed back random access process information to a network side when an SDT mechanism is introduced.

Disclosure of Invention

A main objective of the present disclosure is to provide a random access information reporting method executed by a user equipment and the user equipment, which can implement a more refined RA information report in an SDT scenario, so that a network side can more accurately perform RACH parameter adjustment or SDT configuration parameter adjustment related to SDT based on the refined information in the RA report, thereby improving RACH performance or SDT transmission performance.

According to a first aspect of the present disclosure, a method for random access, RA, reporting performed by a user equipment is provided, including: initiating and completing a small data transmission SDT process; and sending an RA information report related to the SDT process to a network side, wherein the report comprises first information, and the first information is used for representing downlink quality information obtained by the UE just before the SDT process is initiated.

In the above method, the first information may be downlink quality information measured by the UE at or just before a random access procedure for the SDT is triggered.

In the above method, the downlink quality may be reference signal received power, RSRP, information of a downlink path loss reference of the UE-camped cell.

In the above method, the RA information may further include second information indicating small data size information of the UE at or just before the random access procedure is triggered.

In the above method, the small data size may be a size that includes all data packets associated with the radio bearer RB or logical channel with SDT enabled on the network side.

In the above method, the RA information may further include third information, where the third information is used to indicate that the trigger purpose of the random access procedure is for SDT.

In the above method, the RA information may be included in a random access RA report or a connection establishment failure CEF report.

In the above method, the UE may send an RA information report to the network side after receiving an RRC message including an RA information report request from the network side.

In the above method, the RRC message including the RA information reporting request may be a UE information request message; and the message which is sent to the network side by the UE and contains the RA information is a UE information response message.

According to a second aspect of the present disclosure, there is provided a user equipment comprising: a processor; and a memory storing instructions; wherein the instructions, when executed by the processor, perform the above method.

Effects of the invention

According to the random access reporting method executed by the user equipment and the user equipment, a more refined RA information report in an SDT scene can be realized, so that a network side can more accurately adjust RACH parameters related to SDT based on refined information in the RA information report, and the RACH performance can be improved.

Drawings

The above and other features of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:

fig. 1 shows a process for contention-based random access CBRA;

fig. 2 illustrates a procedure for non-contention based random access CFRA;

fig. 3 shows a flow chart of a general procedure of a small data transmission procedure SDT in the prior art.

Fig. 4 shows a schematic diagram of a general method of RA information reporting performed by a user equipment UE according to the present disclosure.

Fig. 5 is a schematic diagram illustrating an RA information reporting method performed by a user equipment UE according to embodiment 1 of the present disclosure.

Fig. 6 is a schematic diagram illustrating an RA information reporting method performed by a user equipment UE according to embodiment 2 of the present disclosure.

Fig. 7 shows a block diagram of a user equipment according to an embodiment of the present disclosure.

Detailed Description

Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the disclosure.

In the present disclosure, the terms "include" and "comprise," as well as derivatives thereof, mean inclusion without limitation; the term "or" is inclusive, meaning and/or.

In this specification, the various embodiments described below which are used to describe the principles of the present disclosure are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the present disclosure as defined by the claims and their equivalents. The following description includes various specific details to aid understanding, but such details are to be regarded as illustrative only. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the present disclosure. Moreover, descriptions of well-known functions and constructions are omitted for clarity and conciseness. Moreover, throughout the drawings, the same reference numerals are used for similar functions and operations.

Embodiments according to the present disclosure are described in detail below with an NR mobile communication system as an example application environment. However, it is to be noted that the present disclosure is not limited to the following embodiments, but is applicable to more other wireless communication systems, such as an LTE system connected to a 5G core network, and the like.

The base station in the present disclosure may be any type of base station, including Node B, enhanced base station eNB, 5G communication system base station gNB; or a micro base station, a pico base station, a macro base station, a home base station, etc.; the cell may be a cell under any type of base station, the cell may be a beam (beam), a Transmission point (TRP), or the base station may be a Central Unit (gNB-Central Unit, gNB-CU) or a Distributed Unit (gNB-Distributed Unit, gNB-DU) that constitutes the base station. Unless otherwise specified, the concepts of cell and base station may be interchanged in this disclosure; the LTE system is also used to refer to the LTE system of 5G and beyond (e.g. referred to as the LTE system, or LTE system that can be connected to a 5G core network), and LTE may be replaced by Evolved Universal Terrestrial Radio Access (E-UTRA) or Evolved Universal Terrestrial Radio Access network (E-UTRAN). Different embodiments may work in combination, for example, the same variables/parameters/terms are interpreted identically in different embodiments. Cancellation, release, deletion, cleanup, and the like may be substituted. Execution, use, and application alternatives. Configuration and reconfiguration may be alternative. Monitoring (monitor) and detection (detect) may be replaced.

Some of the existing concepts and mechanisms involved in the present disclosure are described below. It is noted that some of the nomenclature in the following description is merely exemplary, not limiting, and that other nomenclature is possible.

Physical random access channel resource: physical Random Access Channel (PRACH) resource. The base station broadcasts the parameter configuration of the physical random access channel used by the cell through the system information, and in the present disclosure, the physical random access channel resource PRACH resource may refer to a physical frequency resource and/or a time domain resource and/or a code domain resource (e.g., preamble) used for random access.

Random access channel: random Access Channel, RACH. The RACH in this disclosure may refer to either a transmission channel RACH or a physical random access channel PRACH, and is not distinguished. RACH parameters/configuration refers to radio configuration for implementing a random access function, and includes related configurations of PRACH, such as maximum preamble transmission times, power ramping parameters, a random access response receiving window size, MAC contention resolution timer configuration, PRACH time-frequency resource configuration, message 1 (i.e., preamble) subcarrier spacing, configuration (configured by SSB-RACH-contention and preamble information elements) for indicating number information of Synchronization channel blocks (SSBs) corresponding to each RACH Occasion (RO) and number of contention-based random preamble preambles corresponding to each SSB, backoff parameters (in a scaling factor bi information element), and the like.

Random access, RA, procedure:

in the existing NR/LTE mechanism, there are two random access procedures: contention Based Random Access (CBRA) and non-Contention Based Random Access (i.e., contention Free Random Access (CFRA)). The CBRA process is shown in fig. 1 and includes four steps: the first step, is used for UE to send message 1 (namely random access preamble) to the base transceiver station; the second step is that: the UE receives a message 2 (namely Random Access Response, RAR) from the base station; the third step: UE sends message 3 (uplink transmission scheduled by uplink grant in message 2), where the message 3 is generally used to send UE identifier, RRC message for Radio Resource Control (RRC) connection establishment/recovery/re-establishment, UE contention resolution identifier for random access contention resolution, and the like to the base station, and in early data transmission, user plane data may also be included; the fourth step: the UE receives a message 4 (i.e. a message for contention resolution) from the base station. The PRACH resource used in CBRA is shared by a plurality of UE, and when the UE completes the four steps of CBRA random access and the competition solution is successful, the random access process is successfully completed. The CFRA procedure is shown in fig. 2 and is divided into two steps: the first step is as follows: for the UE to send message 1 (i.e. random access preamble) to the base station; the second step is that: the UE receives a message 2 (i.e., random Access Response, RAR) from the base station. After successfully receiving message 2 associated with message 1, the UE considers that the CFRA procedure is successfully completed. The CFRA generally allocates a dedicated PRACH resource, such as a preamble (referred to as step 0 in fig. 2), to the UE in advance by the base station, so that no contention exists. A two-step random access procedure is being introduced in the current NR. And combining the first step and the third step in the four-step random access process in the same step to send the called message A. That is, the message a contains a random access preamble and a PUSCH payload associated therewith, and the content of the PUSCH payload is consistent with that contained in the message 3, which may contain RRC message, or user plane data, MAC control element such as buffer status report and UE identity. The second step and the fourth step are combined into the same step called message B. The message B is a response to the message a in the two-step random access process, and the content of the message B is similar to the content of the

messages

2 and 4, and may include a response for contention resolution (contention resolution flag, random access preamble flag, UE flag, etc.), a backoff (backoff) indication, a time advance command, an uplink grant, and may also include a response RRC message corresponding to the RRC message included in the response message a. Compared with four-step random access, the two-step random access process can shorten the time delay of the random access. Generally, two-step random access adopts a random access resource configuration different from that of four-step random access.

The UE may trigger a random access procedure in various situations, such as initial access performed to transition from an RRC idle state or an RRC inactive state (RRC inactive) to an RRC connected state, a beam recovery request, handover (also referred to as synchronization reconfiguration in NR), and so on. And after the random access process is triggered, the UE selects whether the initiated random access process is a two-step random access type or a four-step random access type according to the configuration of the network side and the measurement result of the UE. In addition, the UE may fall back to the four-step Random Access procedure in the two-step Random Access, for example, when receiving a fallback Random Access Response (fallback rar) sent by the network side, or when the number of times of sending the two-step Random Access attempt message a exceeds a configured maximum number of times. The random access procedure described in this disclosure includes, but is not limited to, the above-described random access procedure.

RA information reporting:

in the current NR system, there are three main scenarios in which the UE reports a report related to RA information to the network side.

In the first RA information Report, the UE records its RA information for each successfully completed random access procedure in the variable VarRA-Report. For a random access report (referred to as an RA report) in which information of a successfully completed random access procedure is recorded, the base station may issue a UE information request UEinformationRequest message to the UE, where the UE information request message includes an RA-report request indication (RA-report req information element) for requesting the UE to report a saved RA report of the random access procedure. After receiving the UEinformationRequest message including the indication, the UE includes the saved RA report in a UE information response ueinformationreport message and reports the UE information response UEinformationRequest message to the base station. The base station takes the RA report reported by one UE as a sample. Based on a sufficient number of samples, the base station can analyze whether the current RACH performance meets the requirements, and adjust RACH parameters as needed to improve RACH performance.

The second RA information related report is a Connection Establishment Failure (CEF) report. If the initial access fails (the RRC connection establishment procedure fails or the RRC connection recovery procedure fails), the corresponding CEF report also stores the random access information of the random access procedure executed in the RRC connection establishment/recovery procedure. If the UE has a stored CEF report in the variable VarConnEstFailReport, the UE may include a connEstFailInfoAvailable information element in an RRC message, such as an RRC recovery complete message, to inform the base station that the stored CEF report exists thereon. The base station sends a UEinformationRequest message to the UE, where the UEinformationRequest message includes a CEF report request indication (connEstFailReportReq information element) for requesting the UE to report the stored CEF report information. After receiving the UEinformationRequest message including the indication, the UE includes the saved CEF report (connectitfailreport information element) in the ueinformationreport message and reports it to the base station.

The third RA information related report is a Radio Link Failure (RLF) report. For example, when a radio link fails due to a random access failure, the corresponding radio link failure report also stores the corresponding random access information. If the UE has the stored RLF Report in the VarRLF-Report, the UE will include an RLF-InfoAvailable information element in an RRC message, such as an RRC recovery complete message, to inform the base station that the stored RLF Report exists. The base station sends a UE information request message to the UE, where the UE information request message includes a radio link failure report request indication (RLF-report req information element) for requesting the UE to report the stored RLF report information. Upon receiving the UEinformationRequest message including the indication, the UE reports the saved RLF Report (RLF-Report information element) to the base station included in the ueinformationreport message. If a random access procedure is performed in the RLF procedure (e.g. RLF is triggered due to a random access failure), the RLF report includes information about the random access procedure.

In general, the RA report refers to the first RA information report described above. In the present disclosure, it is considered that the SDT mechanism occurs in the RRC inactive state, which is similar to the initial access, as the RRC connection resume message is included in message 3 or message a of the random access. Based on this, the RA report may also comprise a CEF report, which RA information may also apply to the RA information contained in the CEF report.

In LTE, the RA report mainly includes two pieces of information about the random access procedure, one is a number of random access PREAMBLE TRANSMISSIONs (number of random access PREAMBLEs) for indicating the number of random access PREAMBLE TRANSMISSIONs in the random access procedure, which corresponds to the PREAMBLE _ TRANSMISSION _ COUNTER count value of the MAC layer; the other is a contention detection indication (contentioned) for indicating whether contention is detected for at least one transmitted random access preamble. The RACH parameters that the base station may adjust may include RACH resource configuration, random access preamble division (e.g., preamble grouping division into dedicated preambles, a-group and B-group), RACH backoff (backoff) parameters, RACH transmission power control parameters, etc.

The network optimization structure of the NR system of release 16 follows the above framework in LTE and is enhanced in combination with NR characteristics such as beam characteristics and the like.

For the RA report, the NR system supports the UE to store RA information corresponding to a plurality of random access procedures. When the UE successfully completes a random access process, the UE judges that if the number of RA-Report items (number of entries) in a random access Report list RA-Report list stored in a current variable VarRA-Report of the UE is less than the maximum number of RA reports maxRAREPort supported by the system, the UE adds a new item in the VarRA-Report for recording information of the successfully completed random access process. The information of one random access procedure includes: and sending cell information (global cell identification, tracking area code or physical cell identification and carrier frequency) of the random access preamble, random access target information and random access public information. The random access public information includes reference downlink frequency information (such as absolute frequency of Point a, subcarrier spacing, bandwidth location information locationandwidth, etc.) associated with the random access process and RA information associated with each random access attempt arranged according to the occurrence time sequence. The associated RA information of each random access attempt includes a beam index value, a number of consecutive random access attempts on the beam (i.e. the number of sending consecutive random access preamble corresponding to the beam), indication information of whether random access contention is detected, and indication information of whether Reference Signal Received Power (RSRP) of the beam corresponding to the random access resource used by the random access attempt is higher than a configured threshold value.

The UE is allowed to save up to 8 RA reports in the NR. After entering the RRC idle or inactive state, the UE still stores the RA report generated before. The UE may send the saved RA report to the network side after entering the connected state again.

However, the random access information in the CEF report only stores the random access procedure information when the connection establishment/recovery failure occurred last time, and mainly includes information (represented by perralnfist information element) of each random access attempt in the random access procedure. In addition, the CEF report includes a numberofconnmail information element indicating the latest value of the RRC establishment or RRC recovery procedure that continuously fails in the same cell independently of the state transition.

In the currently-performed RA report optimization of release 17, the RA report under the two-step random access procedure is mainly enhanced. Possible enhancements include the inclusion of type information for two-step random access in the RA report when the UE performs a two-step random access procedure, backoff information for the two-step random access procedure to backoff to a four-step random access procedure, downlink quality measured by the UE before the two-step random access procedure is triggered, etc.

The RA information report in the present disclosure is not limited to the RA information report in the existing mechanism described above, and other commands, such as SDT information report, may be made.

Small data transfer SDT mechanism

One of the research goals of the small data transmission SDT project is to implement small data packet transmission in RRC _ INACTIVE state. As shown in fig. 3, in the SDT procedure based on random access, the UE sends a small data transmission request to the network side through the dedicated PRACH resource of the SDT in the random access procedure, and the network side knows that the UE will perform small data transmission in the RRC _ INACTIVE state, so that the UE is not configured to enter the RRC connected state. And then, the UE carries the small data in the message A of the two-step random access process or the message 3 of the four-step random access process and sends the small data to the network side, wherein the message A or the message 3 simultaneously contains an RRC recovery request message. If all the small data are successfully sent in the message 3 or the message A (even if the data cache corresponding to the SDT-enabled radio bearer or the logical channel is empty), the UE determines that the SDT process is ended after receiving a response message containing an RRC release message from the network side; if the small data is not completely transmitted (i.e. there is uplink small data that has not been transmitted in the uplink buffer of the UE), after the random access is completed, the Network side schedules the UE to complete uplink or downlink small data transmission through a Radio Network identifier (e.g. Cell-Radio Network temporary identifier (C-RNTI)) dedicated to the UE, and when all the small data transmission is completed, the SDT process is completed. In the SDT process, if the UE has non-SDT uplink data arriving, the UE may execute uplink data transmission by sending a request indication to the network side or autonomously returning to the conventional non-SDT process. In the whole SDT process, the UE is kept in an RRC _ INACTIVE state, so that the signaling overhead brought by the traditional data transmission process is greatly reduced, the energy consumption of the UE is saved, and meanwhile, the time delay of data transmission can be shortened. According to the current discussion of 3GPP, when uplink data arrives, the UE determines whether to transmit data through the SDT procedure based on certain conditions. The UE can initiate and use the SDT procedure to transmit data only if the conditions for initiating the SDT procedure are satisfied. These conditions may include: the network side configures resources for SDT (such as PRACH configuration dedicated to SDT), radio Bearers (RBs) or logical channels associated with uplink data to be transmitted of the UE through system information or UE-dedicated signaling, and enables the use of the SDT process, the downlink quality of a primary cell of the UE (i.e., a cell camped in RRC _ INACTIVE state) is greater than or equal to a configured link quality threshold TH1, the size of the uplink data to be transmitted of the UE is less than or equal to a configured data size threshold TH2, and the like. It should be noted that the SDT does not limit the name of the mechanism for transmitting small data in the RA procedure, and other names, such as early data transmission, may be used.

The method mainly provides a solution to the problem of how to report the RA information by the UE in the SDT mechanism, and the following embodiments of the method provide specific implementation manners for the problem.

As shown in fig. 4, the RA information reporting method executed by the UE of the present disclosure includes: step S410, step S420, and step 430. In step S410, the UE performs and completes the SDT procedure. When uplink data arrives, the UE judges that the uplink data meets the conditions for executing the SDT, and then the data is sent through the SDT process. In step S420, the UE saves the RA information in the SDT procedure in one UE variable, where the RA information refers to RA information associated with the SDT procedure. In step S430, the UE sends a report containing RA information related to the SDT procedure to the network side. The report includes the RA information related to the SDT procedure stored in step S420.

According to the above method, RA information or SDT-related parameter information for relating to the SDT procedure is included in the RA information report transmitted to the network side. Therefore, more refined RA information reporting in an SDT scene can be realized, so that the network side can more accurately adjust RACH parameters or SDT related configuration parameters based on the SDT related information in the report, and the RACH performance or the SDT performance can be improved.

Example 1

The present embodiment provides a RA information reporting method under an SDT mechanism performed on a UE.

Step S110: the UE completes the random access procedure for SDT.

The type of the random access procedure may be a four-step random access procedure or a two-step random access procedure. The random access procedure for SDT refers to that an RA attempt using SDT-specific resources is performed in a random access procedure, for example, an RA preamble (preamble) for SDT-specific is sent in the random access procedure. The random access procedure is triggered for SDT and therefore also includes before this step:

step 100: the UE determines to initiate the SDT procedure.

The UE completes the random access procedure for SDT considering both success and failure. For the former, the UE may successfully complete the random access procedure for SDT, or the UE may successfully complete the SDT procedure. Preferably, the successfully completing the SDT procedure is that the UE successfully receives the RRC release message after completing the small data transmission in the SDT procedure, and ends the SDT procedure. Alternatively, the successful completion refers to when the last uplink transmission for the small data transmission is completed or acknowledgement information corresponding to the uplink transmission is received (e.g., a successful reception acknowledgement of the MAC layer or the RLC layer). For a scenario where the random access procedure fails, the UE completing the random access procedure for SDT may also be that the random access procedure for SDT fails to complete, or the SDT procedure fails, for example, an RRC timer used for monitoring SDT expires, or a small data packet transmission fails to receive a corresponding downlink acknowledgement, or the number of times of a small data packet transmission failure exceeds a configured threshold, or the small data transmission is interrupted, for example, the small data transmission is terminated due to an uplink alignment timer timeout or a cell reselection. Preferably, the RRC timer is started when the UE initiates the SDT procedure, or when the UE initiates the RRC recovery procedure in the SDT procedure or initiates sending of the RRC recovery request message, and is stopped when the UE receives the RRC release message. Preferably, the timer is T319.

In one implementation, if the UE-initiated SDT procedure fails, such as an RA procedure failure (the number of RA attempts, i.e., RA preambles, sent for SDT exceeds a configured threshold), the UE may fall back to the conventional non-SDT procedure to transmit data. In this case, the UE completes the random access procedure for SDT may also be understood as the UE completes the non-SDT RA procedure after falling back to the conventional non-SDT RA procedure.

Step S120: the UE records the RA information for the random access procedure for SDT in step S110 in an RA information report. The content of the RA information includes one or more of the following information:

the first information: downlink quality information measured by the UE at or just before the random access procedure trigger.

Preferably, the downlink quality information is measurement value information of a downlink path loss reference of a serving cell (or a camped cell or a primary cell) obtained by the UE. Preferably, the measurement value information is associated with a Reference Signal measured Power value (RSRP), such as the measurement value information is used to identify a specific value of RSRP or a range of RSRP values.

And second information: the small data size information of the UE at the time of the random access procedure trigger or just before the random access procedure trigger may also be described as small data size information for determining the initiation of the SDT procedure. The UE compares the small data size value with a data size threshold value configured by the network side to confirm whether an SDT process can be initiated to complete the sending of the small data.

The small data size, also referred to as a small data amount, refers to the size of small data transmitted by initiating the SDT procedure. Preferably, the small data size includes a size of a data packet associated with a Radio Bearer (RB) or a logical channel of which the network side enables SDT. The specific calculation method for determining the small data amount when the UE initiates the SDT procedure is not limited in this disclosure. Preferably, the small Data Packet may be all Data packets in a Packet Data Convergence Protocol (PDCP) buffer or all Data packets in a Radio Link Control (RLC) buffer or a Media Access Control (MAC) layer Data Packet. The Data packet may be one or a combination of multiple PDCP Service Data Unit (SDU), PDCP Protocol Data Unit (PDU), RLC SDU, RLC PDU, MAC SDU, MAC PDU, MAC CE, physical layer transport Data block, and the like. The Radio Bearer may be a Data Radio Bearer (DRB) or a Signaling Radio Bearer (SRB). Optionally, the SRB does not contain SRB0.

And third information: the raPurpose information element is set as the trigger purpose of the random access procedure, i.e. SDT. The raPurpose is used for recording the trigger purpose of the random access procedure, or is used for indicating the random access scenario in which the random access report item is triggered. The raPurpose indicator set to SDT in this embodiment is used when the random access procedure is for SDT.

Fourth information: for indicating whether there is a subsequent (subsequent) uplink transmission in the SDT procedure. The subsequent uplink transmission refers to uplink transmission of other small data occurring after the message 3 or the message a in the SDT procedure except for the small data contained in the message 3 or the message a in the random access procedure.

Fifth information: for indicating the number of subsequent (subsequent) uplink transmissions in the SDT procedure. The subsequent uplink transmission refers to uplink transmission of other small data occurring after the message 3 or the message a in the SDT procedure except for the small data contained in the message 3 or the message a in the random access procedure. The number of subsequent uplink transmissions refers to the number of newly transmitted MAC PDUs in the MAC layer during subsequent uplink transmissions, and does not include the number of retransmitted data packets. The number of uplink grants for new transmissions received by the SDT procedure may be expressed in addition to the number of other uplink grants for new transmissions included in the random access response.

Sixth information: the time elapsed from initiation to completion of the SDT procedure. The SDT completion refers to completion of small data transmission in the SDT process, and may be successful completion or failed completion, which is described in step S110.

Seventh information: the time elapsed from the completion of random access to the completion of the SDT procedure in the SDT procedure. The random access completion refers to that the UE considers that the random access process is successfully completed when the random access contention resolution is successful. The SDT process is completed as described in the above sixth information, and is not described herein again.

Eighth information: the SDT procedure is (no) indication information to enter the connected state. It can also be stated as yes (no) that the RRC recovery message sent from the network side is received in the SDT procedure.

Ninth information: yes (no) non-SDT data arrives during SDT. It can also be stated that yes (no) in the SDT procedure indicates to the base station that there is information of non-SDT data arriving, or whether the SDT procedure falls back to the conventional data transmission procedure (fall-back procedure) because of the non-SDT data arriving. Preferably, the non-SDT data includes a data packet not associated with a Radio Bearer (RB) or a logical channel of the network side capable of SDT, or data that does not conform to a data type required by small data transmission, for example, the data packet does not correspond to a service type required by SDT transmission. The information that the base station knows that the non-SDT data arrives may be that a Buffer Status Report (BSR) associated with the non-SDT data is sent to the base station, or that a random access preamble sending or an RRC recovery request message fallback to a conventional non-SDT procedure is initiated because the non-SDT data arrives in the SDT procedure.

Tenth information: small data size information actually transmitted in the SDT procedure. The small data size information may refer to the small data size information in the second information, which is not described herein again.

Eleventh information: a downlink quality threshold value TH1 for determining whether an SDT procedure can be initiated. The threshold TH1 may be configured to the UE through system broadcast information or RRC dedicated signaling, and is used for the UE to determine whether to initiate an SDT procedure to send data by comparing downlink quality with the threshold TH1 after uplink data arrives. Preferably, the threshold is an RSRP threshold.

Twelfth information: a data size threshold value TH2 for determining whether the SDT procedure can be initiated. The threshold TH2 may be configured to the UE through system broadcast information or RRC dedicated signaling, so that the UE determines whether to initiate an SDT procedure to send data by comparing the size of the data with the threshold TH2 after uplink data arrives.

Thirteenth information: information indicating the latest value of an RRC establishment or RRC recovery procedure, which is not used for the SDT procedure, continuously failed in the same cell independently of state transition. Preferably, the indication information multiplexes a numberofconnmail information element. When the UE fails to establish or recover the RRC connection in the same cell (e.g. time out of T300 or T319), the UE increments the thirteenth information stored thereon by 1. The same cell means that the current cell identity of the UE with a connection establishment failure or a connection recovery failure is the same as the associated cell identity in a report variable (e.g., varConnEstFailReport) stored in the UE.

Fourteenth information: information indicating the latest value of an RRC recovery procedure, which continuously fails in the same cell, refers to an RRC recovery procedure for the SDT procedure. When the UE fails to perform the RRC connection recovery procedure in the same cell (e.g. T319 times out) and the RRC connection recovery procedure is for SDT, the UE increases the fourteenth information stored thereon by 1. The same cell means that the current cell identity of the UE which fails in RRC connection recovery is the same as the cell identity associated in the report variable stored on the UE.

Fifteenth information: information indicating the latest values of RRC establishment or RRC recovery procedures that continuously fail in the same cell, the RRC recovery procedures including both RRC recovery procedures for SDT procedures and non-SDT procedures. When the UE fails to perform an RRC connection recovery procedure in the same cell (e.g., T319 times out) or fails to establish an RRC connection (e.g., T300 times out), the UE increments the fifteenth information stored thereon by 1. The same cell means that the current cell identity of the UE which fails in RRC connection recovery is the same as the cell identity associated in the report variable stored on the UE.

In one implementation, the RA information report is the first medium RA information report, i.e., the RA report, described above. In this case, the UE adds an entry RA-Report in the RA Report list RA-Report list in the RA Report variable (e.g., varRA-Report) for recording RA information of the random access procedure completed in step S110. Optionally, the UE adds an entry (entry) RA-Report to record the completed random access procedure information in an RA Report list RA-Report list in an RA Report variable VarRA-Report when the following conditions are satisfied: the number (number of entries) of RA-Report entries in a random access Report list RA-Report list stored in a current variable VarRA-Report is less than the maximum RA Report number maxRAreport supported by the system; and the number of Public Land Mobile Networks (PLMNs) stored in the VarRA-Report is equal to the set maximum value maxPLMN and the peer PLMN (EPLMN) list is a subset of the PLMN list PLMN-identylist stored in the VarRA-Report or the EPLMN list is equal to the PLMN list PLMN-identylist stored in the VarRA-Report.

In another implementation, the RA information report is the second RA information report, i.e., the CEF report, described above. In this case, the UE adds and sets the above RA information in a CEF report variable (e.g., varConnEstFailReport).

In yet another implementation, the RA information report is not limited to being the existing RA report, CEF report, or RLF report described above; other types of UE reports are also possible, such as reports for reporting SDT procedure information.

Example 2

The embodiment provides a method for reporting RA information under the SDT condition implemented on a UE.

Step S210: the UE receives a first RRC message containing request information from a network side. The request information is used for requesting the UE to report the report containing the RA information or the SDT process information saved by the UE.

Preferably, the first RRC message is a UEinformationRequest message, and the request information is an RA report request indication (RA-ReportReq information element) or a CEF report request indication (connEstFailReportReq information element).

Step S220: the UE sends a second RRC message containing the RA information report associated with the SDT to the network side, for responding to the first RRC message received in step S210.

Preferably, the second RRC message is a UEinformationResponse message, and the RA information report is included in an RA-ReportList information element or a CEF report (ConnEstFailReport information element).

The UE sends a network side RA information report which comprises one or more RA information from the first information to the twelfth information. The first to twelfth information are the same as the first to fifteenth information in embodiment 1, and are not described herein again.

Example 3

The embodiment provides a method for judging the end of the SDT process failure by the UE in the RRC _ INACTIVE state.

Step S310: the UE initiates the SDT procedure.

The UE initiating the SDT procedure is performed after the UE determines that all conditions specified for initiating the SDT procedure are satisfied. The conditions that need to be satisfied in the SDT initiating process are described above, and are not described herein again.

Preferably, in this step, the UE starts a timer for monitoring the SDT procedure, which is described in embodiment 1.

And 2, step: in the SDT process, when the number of transmission times corresponding to the RLC layer data packet, i.e., RLC SDU, associated with the small data transmission of the UE is equal to or exceeds a configured threshold, the UE determines that the small data transmission fails, the SDT process fails, and the SDT process is ended. Preferably, the operation of the UE determining that the small data transmission fails and ending the SDT procedure is performed in an RRC layer of the UE. Under such a limitation, the step further includes determining that the small data transmission fails and ending the SDT procedure after the UE RRC layer receives an indication from the RLC layer that the maximum number of retransmissions has been reached. Preferably, the RLC refers to an RLC associated with an SDT-enabled RB or logical channel.

The UE ending the SDT procedure includes one or more of:

operation 1: stopping a timer for monitoring the SDT procedure;

operation 2: resetting the MAC;

operation 3: deleting a key derived in the SDT process;

and operation 4: reestablishing RLC entities corresponding to all RBs;

operation 5: suspend all SRBs and DRBs except SRB 0;

operation 6: the lower layer suspend encryption and integrity protection is configured.

Operation 7: the operation of entering the RRC _ IDLE state is performed and the release reason is an RRC recovery failure or an SDT failure. The operation of performing the entering into the RRC IDLE state is described in section 5.3.11 of 3GPP specification 38.331.

When the SDT procedure is not an SDT based on a random access procedure but an SDT based on a Configured granted Grant (Configured Grant), the following operations are further included:

operation 8: releasing the configured CG configuration for SDT;

operation 9: the previously saved CG configuration for SDT is discarded.

The number of transmissions is also the number of transmissions, which may be expressed as RETX _ COUNT; the threshold value is expressed as maxretrhreshold. Preferably, during the SDT procedure, the timer for monitoring the SDT procedure may be running. Preferably, the data packet refers to a data packet that is not included in message 3 or message a for transmission, and is not a data packet sent by using an uplink resource corresponding to an uplink grant in a random access response, that is, the data for subsequent uplink transmission in the foregoing embodiment. The UE executes subsequent uplink transmission after the random access process is completed, that is, when the subsequent uplink transmission is executed, the UE has finished the random access process, and at this time, the random access relevant timer is not in a running state, such as the random access response window timer ra-ResponseWindow, the random access contention resolution timer ra-ContentionResolutionTimer, and the message B response window timer msgB-ResponseWindow.

Fig. 7 is a block diagram representation of a user device 70 according to an embodiment of the disclosure. As shown in fig. 7, the user equipment 70 includes a processor 710 and a memory 720. Processor 710 may include, for example, a microprocessor, a microcontroller, an embedded processor, or the like. The memory 720 may include, for example, volatile memory (e.g., random access memory RAM), a Hard Disk Drive (HDD), non-volatile memory (e.g., flash memory), or other memory, among others. The memory 720 has stored thereon program instructions. The instructions, when executed by the processor 710, may perform the above-described random access reporting method in the user equipment as detailed in the present disclosure.

The program running on the apparatus according to the present disclosure may be a program that causes a computer to realize the functions of the embodiments of the present disclosure by controlling a Central Processing Unit (CPU). The program or information processed by the program may be temporarily stored in a volatile memory (such as a random access memory RAM), a Hard Disk Drive (HDD), a nonvolatile memory (such as a flash memory), or other memory system.

A program for implementing the functions of the embodiments of the present disclosure may be recorded on a computer-readable recording medium. The corresponding functions can be realized by causing a computer system to read the programs recorded on the recording medium and execute the programs. The term "computer system" as used herein may be a computer system embedded in the device and may include an operating system or hardware (e.g., peripheral devices). The "computer-readable recording medium" may be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a recording medium that stores a program for short-term dynamics, or any other recording medium that is readable by a computer.

Various features or functional blocks of the devices used in the above-described embodiments may be implemented or performed by circuitry (e.g., a single or multiple chip integrated circuits). Circuitry designed to perform the functions described herein may include a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The circuit may be a digital circuit or an analog circuit. Where new integrated circuit technology has emerged as a replacement for existing integrated circuits due to advances in semiconductor technology, one or more embodiments of the present disclosure may also be implemented using such new integrated circuit technology.

Further, the present disclosure is not limited to the above-described embodiments. While various examples of the embodiments have been described, the present disclosure is not so limited. Fixed or non-mobile electronic devices installed indoors or outdoors may be used as terminal devices or communication devices, such as AV devices, kitchen devices, cleaning devices, air conditioners, office equipment, vending machines, and other home appliances.

As above, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. However, the specific configuration is not limited to the above embodiment, and the present disclosure also includes any design modification without departing from the gist of the present disclosure. In addition, various modifications can be made to the present disclosure within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present disclosure. Further, components having the same effects described in the above embodiments may be substituted for each other.

Claims

1. A method for reporting Random Access (RA) information executed by user equipment comprises the following steps:

initiating and completing a Small Data Transmission (SDT) process; and

and sending an RA information report related to the SDT process to a network side, wherein the report contains first information, and the first information is used for representing downlink quality information obtained by the UE just before the SDT process is initiated.

2. The method for reporting random access RA information of claim 1, wherein,

the first information is downlink quality information measured by the UE at or just before a random access procedure trigger for SDT.

3. The method for reporting random access RA information of claim 1 or 2, wherein,

and the downlink quality is Reference Signal Received Power (RSRP) information of a downlink path loss reference of a cell where the UE resides.

4. The method for reporting random access RA information of claim 1, wherein,

the RA information further includes second information indicating small data size information of the UE at or just before the random access procedure is triggered.

5. The method for reporting random access RA information of claim 4, wherein,

the small data size is the size of all data packets associated with the radio bearer RB or logical channel containing SDT enabled by the network side.

6. The method for reporting random access RA information of claim 1, wherein,

the RA information further includes third information indicating that a trigger purpose of the random access procedure is for SDT.

7. The method for reporting random access RA information of claim 1, wherein,

the RA information is contained in a random access RA report or a connection setup failure CEF report.

8. The method for reporting random access RA information of claim 1, wherein,

and after receiving the RRC message containing the RA information reporting request from the network side, the UE sends the RA information report to the network side.

9. The method for reporting random access RA information as claimed in claims 1 and 7, wherein,

the RRC message containing the RA information reporting request is a UE information request message; and the message which is sent to the network side by the UE and contains the RA information is a UE information response message.

10. A user equipment, comprising:

a processor; and

a memory storing instructions;

wherein the instructions, when executed by the processor, perform the method for random access, RA, information reporting according to any of claims 1 to 9.