Wireless communication method and device for random access channel and computer readable medium

Abstract

The present application provides a wireless communication method, comprising: receiving an RA (Random Access) request preamble in one or more ROs (PRACH occasion) associated with the same SSB or associated with a different SSB; in response to the RA request preamble received by the BS, corresponding one or more RA responses are transmitted.

Description

Technical Field

[0001] The present disclosure relates generally to a random access procedure, and more particularly to PRACH or Msg1 repetition. Background Art

[0002] Wireless communication technology is a key component of the increasingly interconnected global communication network. Wireless communication relies on the accurate allocation of time and frequency resources to transmit and receive wireless signals.

[0003] The coverage of channel accessibility is one of the factors that operators consider for commercial use of cellular communication networks, as this may have a direct impact on the quality of service of wireless communication. In addition, in most cases of practical applications, uplink (UL) coverage may be a bottleneck, especially in high-frequency cell applications. Some uplink coverage enhancement methods can be considered, such as PUSCH (Physical Uplink Shared Channel) repetition, PUCCH (Physical Uplink Control Channel) repetition and Msg3 (scheduled transmission) repetition technology, which allow UE to transmit UL data on multiple consecutive time slots. This can improve the reception success rate of the base station (BS), especially when the user equipment (UE) is located at the edge of the cell. Summary of the invention

[0004] This summary is a brief description of certain aspects of the disclosure. It is not intended to limit the scope of the disclosure.

[0005] One aspect of the present disclosure provides a wireless communication method, including: setting at least one of the following configurations for a random access (RA) process:

[0006] RA request repetition indicator, used to indicate whether the RA resource set is applicable to RA request repetition;

[0007] RA request scan indicator, used to indicate whether the RA resource set is applicable to RA request scan;

[0008] RA request repetition count, used to determine the number of times the RA request is repeated;

[0009] RA request scan times, used to determine the number of RA request scans;

[0010] An RSRP (Reference Signal Received Power) threshold for repetition, used to determine whether RA request repetition is applicable to the RA process, or to determine which RA request repetition number should be selected from multiple RA request repetition numbers;

[0011] SSB bundle (Synchronization Signal Block bundle) configuration, used to determine the grouping of SSB; or

[0012] RACH resource configuration, used to indicate RACH resources used for transmitting RA request repetition or RA request scanning; and

[0013] RA request repetition or RA request scanning is performed according to at least one of the configurations.

[0014] Another aspect of the present disclosure provides a wireless communication method, comprising: determining an index of a starting PRACH opportunity (Physical Random Access Channel Occasion, RO) by:

[0015] Determine the index of the starting RO = [UE_ID mod [floor (Y / X)]] × X, where Y is the total number of ROs associated with the SSB in the association period of the SSB to RO mapping, X is the number of RA request repetitions, and UE_ID is the UE index;

[0016] Determine the index of the starting RO via signaling or a preset rule between the UE or the BS;

[0017] Determine the index of the starting RO as the first RO in the associated period of the SSB to RO mapping;

[0018] The RA request is transmitted or received repeatedly at X ROs starting from the index of the starting RO.

[0019] Another aspect of the present disclosure provides a wireless communication method, including: transmitting an RA (random access) request preamble in one or more ROs (PRACH occasions) associated with the same SSB or associated with different SSBs; and receiving corresponding one or more RA responses in response to the RA request preamble transmitted by the UE.

[0020] Another aspect of the present disclosure provides a wireless communication method, including: receiving an RA (random access) request preamble in one or more ROs (PRACH occasions) associated with the same SSB or associated with different SSBs; and transmitting corresponding one or more RA responses in response to the RA request preamble received by the BS.

[0021] Yet another aspect of the present disclosure provides a wireless communication device, including a memory storing one or more programs and a processor electrically coupled to the memory, wherein the processor is configured to execute the one or more programs to perform any method or step or a combination thereof in the present disclosure.

[0022] Yet another aspect of the present disclosure provides a non-transitory computer-readable storage medium storing one or more programs, wherein the one or more programs are configured to, when executed by a processor, cause any method or step or a combination thereof in the present disclosure to be performed.

[0023] The above and other aspects and implementations thereof are described in more detail in the drawings, the description and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various exemplary embodiments of the present disclosure are described in detail below with reference to the following drawings. The drawings are provided for illustrative purposes only and only describe exemplary embodiments of the present disclosure to facilitate understanding of the present disclosure. Therefore, the drawings should not be considered as limitations on the breadth, scope or applicability of the present disclosure. It should be noted that for clarity and ease of description, these drawings are not necessarily drawn to scale.

[0025] Figure 1 shows a contention-based random access procedure;

[0026] Figure 2 shows a contention-free random access procedure;

[0027] Figure 3 Example PRACH repetitions with the same SSB and different SSBs are shown;

[0028] Figure 4 Another example PRACH repetition with the same SSB and different SSB is shown;

[0029] Figures 5 to 8 Example preamble partitioning and parameter assignments for PRACH repetitions are shown;

[0030] Figures 9 to 15 An example PRACH opportunity bundling arrangement is shown;

[0031] Fig.16 shows the transmission of RA preambles for legacy and updated UEs in multiple ROs;

[0032] Figure 17 to Figure 18 shows wireless communications of a RA request (Msg1) and a RA response (Msg2) and corresponding ROs and search spaces; and

[0033] Fig.19An exemplary wireless communication system is shown, which can implement the methods and / or steps in the present disclosure. DETAILED DESCRIPTION

[0034] Fig.19 A block diagram of an exemplary wireless communication system 150 according to some embodiments of the present disclosure is shown. The system 150 may perform various methods / steps disclosed below. The system 150 may include components and elements configured to support operational features that need not be described in detail herein.

[0035] System 150 may include a base station (BS) 102 and a user equipment (UE) 104. BS 102 includes a BS transceiver or transceiver module 152, a BS antenna system 154, a BS memory or memory module 156, a BS processor or processor module 158, and a network interface 160. The components of BS 102 may be electrically coupled and communicate with each other via a data communication bus 180 as needed. Similarly, UE 104 includes a UE transceiver or transceiver module 162, a UE antenna system 164, a UE memory or memory module 166, a UE processor or processor module 168, and an I / O interface 169. The components of UE 104 may be electrically coupled and communicate with each other via a data communication bus 190 as needed. BS 102 communicates with UE 104 via a communication channel 192, which may be any wireless channel or other medium known in the art suitable for data transmission as described herein.

[0036] As will be appreciated by those skilled in the art, system 150 may also include, in addition to Figure 1 Any number of modules other than the modules shown. It will be appreciated by those skilled in the art that the various illustrative blocks, modules, circuits, and processing logic described in conjunction with the embodiments disclosed herein can be implemented in hardware, computer-readable software, firmware, or any actual combination thereof. In order to clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are generally described in terms of their functions. Whether such functions are implemented as hardware, firmware, or software depends on specific applications and design constraints on the entire system. People familiar with the concepts described herein can implement such functions in an appropriate manner for each specific application, but such implementation decisions should not be interpreted as limiting the scope of the present disclosure.

[0037] Wireless transmissions from the transmit antenna of UE 104 (referred to in the singular form for convenience, but may include multiple antennas) to the receive antenna of BS 102 (referred to in the singular form for convenience, but may include multiple antennas) are referred to as uplink (UL) transmissions, and wireless transmissions from the transmit antenna of BS 102 to the receive antenna of UE 104 are referred to as downlink (DL) transmissions. According to some embodiments, UE transceiver 162 may be referred to herein as an "uplink" transceiver 162, which includes RF transmitter and receiver circuits that are both coupled to UE antenna 164. A duplex switch (not shown) may couple the uplink transmitter or receiver to the uplink antenna in a time division duplex manner. Similarly, according to some embodiments, BS transceiver 152 may be referred to herein as a "downlink" transceiver 152, which includes RF transmitter and receiver circuits that are both coupled to antenna array 154. The downlink duplex switch may couple the downlink transmitter or receiver to the downlink antenna array 154 in a time division duplex manner. The operation of the two transceivers 152 and 162 is coordinated in time so that the uplink receiver is coupled to the uplink UE antenna 164 for receiving or transmitting over the wireless communication channel 192 at the same time as the downlink transmitter is coupled to the downlink antenna array 154. There may be close synchronization timing with only minimal guard time between changes in duplex direction. The UE transceiver 162 communicates with the BS 102 via the wireless communication channel 192 through the UE antenna 164. The BS transceiver 152 communicates with other BSs (e.g., the second BS 102-2) via the BS antenna 154 of the BS (e.g., the first BS 102) via the wireless communication channel 192. The wireless communication channel 196 can be any wireless channel or other medium known in the art suitable for direct communication between BSs.

[0038] The UE transceiver 162 and the BS transceiver 152 are configured to communicate via a wireless data communication channel 192 and cooperate with an appropriately configured RF antenna device 154 / 164 capable of supporting a specific wireless communication protocol and modulation scheme. In some exemplary embodiments, the UE transceiver 162 and the BS transceiver 152 are configured to support industry standards such as Long Term Evolution (LTE) and 5G standards (e.g., NR). However, it should be understood that the present invention is not necessarily limited to specific standards and related protocols in application. Instead, the UE transceiver 162 and the BS transceiver 152 can be configured to support alternative or additional wireless data communication protocols, including future standards or variants thereof.

[0039] The processor modules 158 and 168 may be implemented or implemented with a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, which are designed to perform the functions described herein. In this manner, the processor module may be implemented as a microprocessor, a controller, a microcontroller, a state machine, etc. The processor module may also be implemented as a combination of computing devices, for example, a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a digital signal processor core, or any other such configuration.

[0040] In addition, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, firmware, software modules executed by the processor modules 158 and 168, respectively, or any practical combination thereof. The memory modules 156 and 166 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. In this regard, the memory modules 156 and 166 may be coupled to the processor modules 158 and 168, respectively, so that the processor modules 158 and 168 can read information from and write information to the memory modules 156 and 166, respectively. The memory modules 156 and 166 may also be integrated into their respective processor modules 158 and 168. In some embodiments, the memory modules 156 and 166 may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions to be executed by the processor modules 158 and 168, respectively. The memory modules 156 and 166 may also include non-volatile memory for storing instructions to be executed by the processor modules 158 and 168, respectively.

[0041] The network interface 160 generally represents hardware, software, firmware, processing logic and / or other components of the base station 102, which enable bidirectional communication between the BS transceiver 152 and other network components and communication nodes configured to communicate with the BS 102. For example, the network interface 160 can be configured to support Internet or WiMAX traffic. In a non-limiting typical deployment, the network interface 160 provides an 802.3 Ethernet interface so that the BS transceiver 152 can communicate with a traditional Ethernet-based computer network. In this way, the network interface 160 may include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)) or one or more core networks 195 for mobile communications. The term "configured for" or "configured to" used herein for a specific operation or function refers to a device, component, circuit, structure, machine, signal, etc., which is physically constructed, programmed, formatted and / or arranged to perform a specified operation or function. The network interface 160 can allow the BS 102 to communicate with other BSs or CNs via a wired or wireless connection.

[0042] For UL (uplink) transmission, PRACH (physical random access channel) may be the main bottleneck of UL coverage. This disclosure proposes a detailed PRACH repetition technology to improve the successful access rate of UL transmission. The UE can use PRACH to request uplink allocation from the base station.

[0043] PRACH is a basic physical channel in wireless communication systems, for example, for LTE and 5GNR. When initiating a random access procedure on a serving cell, the UE may first select a SUL (Supplementary Uplink) or NUL (Normal Uplink) carrier, select a set of random access resources applicable to the current random access procedure, perform variable initialization, and perform a random access (RA) resource selection procedure.

[0044] In the RA resource selection process, the UE may first select an SSB (synchronization signal block) and one or more preambles, and then may select a PRACH opportunity (RO). After selecting the RA resource, the UE may perform the RA preamble transmission process.

[0045] There are contention-based random access (CBRA) and non-contention or contention-free random access (CFRA). Figure 1In the contention-based random access shown in Figure 1, the UE can randomly select a preamble from a pool of preambles shared with other UEs. CBRA is also known as a four-step RACH procedure. In non-contention random access, the preamble is allocated by the base station (BS), and such a preamble is called a dedicated random access preamble. The dedicated preamble can be provided to the user equipment (UE) via different types of signaling. The steps of CFRA are as follows: Figure 2 shown.

[0046] It may be beneficial if the BS (gNB) knows which beam the UE is receiving with the strongest signal. This can be achieved by connecting a specific instance of an SSB (Synchronization Signal Block) to a specific beam. When the UE can measure several detectable beams, the measurement can be performed on the SSB. Each SSB may have a parameter "time index". With the association of the SSB time index with specific RACH resources (e.g., time slot and / or preamble), the UE can use these resources when accessing the cell. Thus, the BS can know which beam the UE prefers.

[0047] In addition, beam establishment during initial access can be achieved by the possibility of associating different SSB time indices with different RACH time / frequency opportunities and / or different preamble sequences. In fact, different SSB time indices can correspond to SSB transmissions in different downlink (DL) beams. The wireless communication network is able to determine the DL beam in which the corresponding UE is located based on the received preamble. This beam can then be used as the initial beam for subsequent DL transmissions to the UE.

[0048] In addition, if the association between the SSB time index and the RACH opportunity is such that a given time domain RACH opportunity corresponds to a specific SSB time index, the wireless communication network can know when in the time domain a preamble transmission from the UE within a specific DL beam will be performed. The wireless communication network can focus the corresponding direction of the beamforming preamble reception of the UL receiver beam.

[0049] In the conventional RA process, the UE can select only one RO and transmit one preamble in one RA process. When a failure occurs in the RA process, the UE can re-execute the RA resource selection and RA preamble transmission process without reselecting the RA resource set.

[0050] To implement the novel and inventive PRACH repetition scheme, the present disclosure provides details of various aspects, including but not limited to its configuration, its RO determination, and RA response reception.

[0051] I. Configuration

[0052] According to some embodiments of the present disclosure, there may be three options for PRACH repetition.

[0053] Option 1: According to Option 1, PRACH repetition can be performed using the same UL beam associated with the same SSB.

[0054] Option 2: According to Option 2, PRACH repetition can be performed using different UL beams associated with the same SSB. This option can be used for UEs without beam correspondence (BC) capability. For ease of description, this option may also be referred to as "scanning", but this naming is not intended to limit the application of this technology.

[0055] Option 3: According to option 3, PRACH repetition can be performed using different UL beams associated with different SSBs. Option 3 can be used to find the strongest UL beam.

[0056] For repetitions with the same SSB (e.g., under Option 1 or Option 2), an "RO bundle" may be defined as consecutive or successive ROs associated with the same SSB. These ROs in the same RO bundle may be within the association period of the SSB to RO mapping or may span multiple association periods. The size of the RO bundle may be determined by the number of repetitions or scans.

[0057] For repetitions with different SSBs (e.g., repetitions according to option 3), an "SSB bundling" may be defined as a set of SSBs where the UE may transmit one or more preambles in multiple ROs associated with different SSBs belonging to the SSB bundle as long as the SS-RSRP (Synchronization Signal Reference Signal Received Power) of these SSBs is above a threshold (e.g., configurable by parameter rsrp-ThresholdSSB).

[0058] To accommodate the above functions and other purposes of PRACH repetition, the BS and / or UE may establish at least one of the following configurations or a combination thereof:

[0059] (1) Msg1 (i.e., PRACH) repetition and / or scanning indication, used to indicate whether the current RA resource set can be used for Msg1 repetition and / or scanning;

[0060] (2) Number of Msg1 repetitions and / or scans, used by the UE to determine the number of Msg1 repetitions and / or scans in a transmission round;

[0061] (3) The RSRP (Reference Signal Received Power) threshold for repetitions, which is used by the UE to determine whether Msg1 repetitions are applicable to the current random access procedure under the current signal conditions, and / or to determine which Msg1 repetition number to select when multiple repetition numbers are configured;

[0062] (4) SSB bundling configuration, used by the UE to determine which SSBs belong to an SSB bundle; and / or

[0063] (5) RACH resource configuration, used by the UE to transmit Msg1 repetitions and / or scans accordingly.

[0064] 1. Msg1 repeat / scan indication

[0065] For the configuration of Msg1 repetition and / or scanning indication, the configuration can be explicitly or implicitly configured, and can be configured separately or simultaneously with other feature indications (for example, small data transmission, redCap (Reduced Capability) UE, Msg3 repetition configuration, etc.).

[0066] Exemplarily, it can be assumed that a UE or RA resource set that supports Msg1 repetition can also support Msg3 repetition. In this case, when the RA resource set indicates that Msg1 repetition is applicable, Msg3 repetition can also be performed in the RA resource set. Similarly, if the RA resource set indicates that Msg3 repetition is applicable, the UE or BS understands that the RA resource set is applicable to Msg1 repetition.

[0067] Exemplarily, it can be assumed that a UE or RA resource set that supports Msg1 repetition does not necessarily support Msg3 repetition. In this case, when the RA resource set only indicates the applicability to Msg1 repetition, Msg3 repetition is not necessarily applicable to the RA resource set. The wireless communication network may need to configure additional RA resource sets that indicate the applicability of Msg1 repetition and the applicability of Msg3 repetition, respectively.

[0068] Exemplarily, the BS and the UE may assume that if the number of Msg1 repetitions (the number of repetitions to be transmitted) is configured, the current RA resource set may be considered applicable to Msg1 repetition regardless of whether the Msg1 repetition indication is configured to indicate the applicability of the RA resource set to Msg1 repetition. Therefore, additional indication overhead may be saved.

[0069] Exemplarily, the BS and the UE may assume that if the number of Msg1 scans (number of repetitions to be transmitted) is configured, the current RA resource set may be considered applicable to Msg1 scan regardless of whether the Msg1 scan indication is configured to indicate the applicability of the RA resource set to Msg1 scan. Therefore, additional indication overhead may be saved.

[0070] Exemplarily, the BS and the UE may assume that, if the SSB bundling configuration is configured, the current RA resource set may be considered applicable to Msg1 repetition with different SSBs (e.g., under option 3 as described above), regardless of whether the Msg1 repetition indication is configured to indicate the applicability of the RA resource set to Msg1 repetition. Therefore, additional indication overhead may be saved.

[0071] Exemplarily, if either the Msg1 repetition indication or the number of Msg1 repetitions and either the Msg1 scan indication or the number of Msg1 scans are configured at the same time, the BS and the UE can understand that the current RA resource set can be considered applicable to Msg1 repetition and Msg1 scan. Therefore, additional indication overhead can be saved.

[0072] Exemplarily, if either the Msg1 repetition indication or the Msg1 repetition number is configured with an SSB bundling configuration at the same time, the current RA resource set can be considered to be applicable to Msg1 repetitions with the same SSB (e.g., under Option 1 and Option 2 as described above) or different SSBs (e.g., under Option 3 as described above). Two examples are provided below.

[0073] Figure 3 An example diagram of PRACH repetition with the same SSB and different SSB is shown in FIG. Figure 3 As shown, PRACH (i.e., Msg1) repetitions (including PRACH repetition 1 and PRACH repetition 2) with the same SSB (e.g., SSB0) are performed; then, PRACH repetitions (PRACH repetition 3 and PRACH repetition 4) with different SSBs (SSB1) are performed. Specifically, PRACH repetition 1 and PRACH repetition 2 belong to the same SSB0 and the same UL beam associated with SSB0 (as shown by the arrow pattern); PRACH repetition 3 and PRACH repetition 4 belong to the same SSB1 and the same UL beam associated with SSB1; finally, PRACH repetition 5 and PRACH repetition 6 belong to the same SSB2 and the same UL beam associated with SSB2. Here, an RO bundle may be defined as consecutive or successive ROs associated with the same SSB. An SSB bundle may be defined as an SSB set, where a UE may transmit one or more preambles in multiple ROs associated with different SSBs belonging to an SSB bundle.

[0074] Figure 4 An example diagram of PRACH repetition with the same SSB and different SSB is shown in FIG. Figure 4As shown, PRACH repetitions with different SSBs are performed first, and then PRACH repetitions with the same SSB set are performed. Specifically, PRACH repetitions 1, 2, and 3 with different SSBs (SSB0, SSB1, SSB3) in the SSB bundle are performed first. Then, PRACH repetitions 4, 5, and 6 with different SSBs (SSB0, SSB1, SSB3) but in the same SSB bundle or set are performed. Here, PRACH repetition 1 and PRACH repetition 4 can have the same UL beam associated with SSB0 (as shown by the arrow pattern); PRACH repetition 2 and PRACH repetition 5 belong to the same UL beam associated with SSB1; similarly, PRACH repetition 3 and PRACH repetition 6 belong to the same UL beam associated with SSB2.

[0075] 2. Msg1 repetition / scan times

[0076] The configuration of the number of Msg1 repetitions / scans may indicate the number of repetitions of PRACH / Msg1. The number of Msg1 repetitions and / or scans may be explicitly or implicitly configured. In addition, the BS and / or UE may establish multiple configurations for different network implementations and / or conditions.

[0077] Exemplarily, the number of Msg1 repetitions and / or scans may be configured as a parameter per BWP (Bandwidth Part); therefore, the number of Msg1 repetitions and / or scans may be configured to be shared by all feature combinations in a specific BWP.

[0078] Exemplarily, the number of Msg1 repetitions and / or scans may be configured as parameters for each FeatureCombination; in this case, the number of Msg1 repetitions and / or scans may be configured separately for all feature combinations in the BWP.

[0079] Exemplarily, the number of Msg1 repetitions and / or scans can be configured for the RA resource set of CFRA, for example, for SI (system information) request, CF-BFR (Contention Free-Beam Failure Recovery), reconfigurationWithSync, etc. For example, this parameter can be introduced into traditional parameters SI-SchedulingInfo, BeamFailureRecoveryConfig, rach-ConfigDedicated, etc.

[0080] Exemplarily, the number of Msg1 repetitions and / or scans may be indicated in a PDCCH (Physical Downlink Control Channel) order (i.e., DCI1_0, downlink control information format 0_1). For example, the first three bits of the reserved bits in DCI1_0 may be used, where a value of "1" may indicate the number 1, a value of 2 may indicate the number 2, and so on.

[0081] 3. Repeated RSRP (Reference Signal Received Power) Threshold

[0082] If both RA resource sets with Msg1 repetition indication and RA resource sets without Msg1 repetition indication are configured in one BWP, it can be considered that the repeated RSRP threshold is a necessary configuration.

[0083] In addition, if multiple repetitions are configured, multiple RSRP thresholds can be configured, corresponding to the multiple repetitions. For example, different configurations for different repetitions can be used when different RSPR thresholds are met. For example, when RSRP indicates weak channel conditions, more repetitions can be transmitted to improve the success rate of joint decoding with multiple repetitions. RSRP thresholds can be used to define conditions for when the PRACH repetition technique must be enabled, or when a specific number of PRACH repetitions should be used.

[0084] Exemplarily, the RSRP repetition threshold may be configured for the RA resource set of CFRA, for example, for SI (system information) request, CF-BFR, reconfigurationWithSync, etc. For example, the parameter may be introduced into the traditional parameters SI-SchedulingInfo, BeamFailureRecoveryConfig, rach-ConfigDedicated, etc.

[0085] 4.SSB Bundle Configuration

[0086] Exemplarily, all transmitted SSBs may be considered as one SSB bundle. In this case, an SSB bundle enable indication may be required to indicate whether one SSB bundle is enabled.

[0087] For example, one or more SSB bundles may be explicitly configured as required by a particular network implementation.

[0088] Exemplarily, the SSB bundling configuration may be configured in a per-BWP parameter manner; in this case, all functional combinations in a particular BWP may share the SSB bundling.

[0089] Exemplarily, the SSB bundle configuration may be configured in a per-FeatureCombination parameter manner; in this case, multiple sets of SSB bundle configurations may be configured separately for all feature combinations in the BWP.

[0090] 5. RACH resource configuration

[0091] The RACH resource configuration may indicate the RO (PRACH opportunity) in the time domain for transmitting PRACH repetitions. For RACH resource configuration, a RO shared with legacy UEs and / or a separate RO may be configured. If a shared RO is used, a separate preamble may be configured. There are two groups of RA preambles, Group A and Group B. Group A may always exist, and Group B exists only under specific configuration in the SIB2 parameters. The determination of Group A and Group B is described in the random access procedure initialization criteria.

[0092] Exemplarily, for the RA resource set that can be used for Msg1 repetition, if there are preambles in group B, there are the following two methods to divide the preambles.

[0093] Method 1.5.1 (such as Figure 5 As shown): First, the preamble codes used for PRACH repetition are divided into group A and group B, and then each preamble code group (ie, group A and group B) is divided into multiple partitions; each partition is associated with a repetition number (eg, 2, 4, or 8 times, etc.).

[0094] As an example, the parameter Msg1-Repetitions-r18 may be introduced into FeatureCombination-r17, indicating that the corresponding RA resource set is applicable to PRACH repetition. Exemplarily, the parameters numberOfGroupAPreamblesPerSSB-ForThisRepetition-r18 and numberOfGroupBPreamblesPerSSB-ForThisRepetition-r18 (in the presence of group B) for each repetition number may be introduced into BWP-UplinkCommon (i.e., on a per-BWP basis) or FeatureCombinationPreambles-r17 (i.e., on a per-FeatureCombination basis). The parameters numberOfGroupAPreamblesPerSSB-ForThisRepetition-r18 and numberOfGroupBPreamblesPerSSB-ForThisRepetition-r18 may indicate the number of preambles of group A and group B used for the repetition number.

[0095] Assuming there are R repetitions, the parameter may appear in the first R-1 entries and not in the last entry. The sum of all numberOfGroupAPreamblesPerSSB-ForThisRepetition-r18 is usually lower than the total number of preambles used for group A. The sum of all numberOfGroupBPreamblesPerSSB-ForThisRepetition-r18 may usually be lower than the total number of preambles used for group B (if any). For group A preambles, the first numberOfGroupAPreamblesPerSSB-ForThisRepetition-r18 i The preambles may be used continuously for the first R-1 entries, and the remaining preambles may be used for the last entry.

[0096] For Group B preambles (if applicable), the preamble numberOfGroupBPreamblesPerSSB-ForThisRepetition-r18 i The preambles can be used continuously for the first R-1 entries, and the remaining preambles can be used for the last entry. An example diagram of the preamble part is shown below.

[0097] Method 1.5.2 (such as Figure 6 According to the method, first, the preamble for PRACH repetition can be divided into multiple partitions, and each partition can be associated with a repetition number. Partitions associated with the same repetition number are allocated to group A or group B. The preambles of group A and group B can be arranged alternately.

[0098] For example, the parameters numberOfPreamblesPerSSB-ForThisRepetition-r18 and numberOfRA-PreamblesGroupA (for r18 if there is a B group) for each repetition number can be introduced into BWP-UplinkCommon (i.e., each BWP) or FeatureCombinationPreambles-r17 (i.e., each FeatureCombination). In addition, the parameter numberOfPreamblesPerSSB-ForThisRepetition-r18 can indicate the number of preambles used for a certain repetition number. Assuming there are R repetition numbers, the parameter numberOfPreamblesPerSSB-ForThisRepetition-r18 can appear in the first R-1 entries and not in the remaining entries. The sum of all numberOfPreamblesPerSSB-ForThisRepetition-r18 can generally be lower than the total number of preambles used for PRACH repetitions.

[0099] For the PRACH repeated preamble, numberOfPreamblesPerSSB-ForThisRepetition-r18 i Preambles can be used continuously for the first R-1 entries, and the remaining preambles can be used for the remaining entries. For each repetition, if group B exists, the first numberOfRA-PreamblesGroupA preambles can be used for group A, and the remaining preambles can be used for group B.

[0100] Exemplarily, if there are Msg1 repetition and Msg1 scanning sharing RO and B groups, two methods are disclosed below to divide the preamble code.

[0101] Method 1.5.3 (such as Figure 7 As shown in FIG. 1 ): According to this example, the preamble code can be divided into group A and group B, and then each preamble code group (i.e., group A and group B) can be divided into multiple partitions. Each partition can be associated with a repetition number or scan. Figure 7 As shown, group A and group B each include partitions associated with repetition numbers of 2, 4, and 8. The partitions of group A may be continuous with each other, and the partitions of group B may be continuous with each other.

[0102] Method 1.5.4 (such as Figure 8 According to this example, the preamble can be divided into multiple partitions, and each partition can be associated with a repetition number or scan. Each partitioned preamble can be assigned to group A or group B. Figure 8 As shown, the partitions of group A and the partitions of group BB can be arranged alternately.

[0103] II.RO Determination

[0104] As described above, an RO bundle can be defined as consecutive or successive ROs associated with the same SSB. These ROs in the same RO bundle can be within the association period of the SSB to RO mapping or can span multiple association periods. The size of the RO bundle can be determined by the number of repetitions or scans. As described below, three example methods can be used to determine the starting RO of an RO bundle.

[0105] Method 2.1: The total number of ROs associated with one SSB in the relevant period of SSB to RO mapping is equal to Y, where Y is zero or a positive integer, and these ROs can be represented as RO0, RO1, ..., RO(Y-1); the number of repetitions (or scans) can be represented as X. For example:

[0106] If Y≤X (Y is equal to or less than X), the starting RO of the RO bundle is RO0;

[0107] If Y>X (Y is greater than X), the starting RO of the RO bundle can be determined by the following equation (1):

[0108] RO = {UE_IDmod[floor(Y / X)]}×X ... equation (1);

[0109] Where floor(Y / X) obtains the largest integer less than or equal to Y divided by X, and the mod function, labeled mod(), finds the remainder of the result of dividing UE_ID by the floor function floor(Y / X). Additional examples are given below.

[0110] Example 1:

[0111] like Fig. 9 As shown, in the case of Y=8 and X=2, the candidates for the starting RO are {RO0, RO2, RO4, RO6}. Specifically, in the association period of SSB to RO mapping, there are 8 ROs associated with SSB0. When UE_ID=0, equation (1) can be written as RO={0mod[Floor(8 / 2)]}×2=0. Therefore, the starting RO=0. For UE_ID=1, the starting RO={1mod[Floor(8 / 2)]}×2=1×2=2. Therefore, the starting RO is RO2. Following the same rule, the starting RO for UE_ID=2 is RO4, and the starting RO for UE_ID=3 is RO6. RO0 and RO1 are in the same bundle. RO2 and RO3 are in the same bundle, and so on. ··

[0112] Example 2:

[0113] like Fig.10 As shown, in the case of Y=8 and X=3, the candidates for the starting RO are {RO0, RO3}. The starting RO of UE_ID=0 is RO0, and the starting RO of UE_ID=3 is RO3.

[0114] Example 3:

[0115] like Fig.11 As shown, in the case of Y=8 and X=4, the candidates for the starting RO of RO bundling are {RO0, RO4}. The starting RO of UE_ID=0 is RO0, and the starting RO of UE_ID=1 is RO4.

[0116] Example 4:

[0117] like Fig.12 As shown, in the case of Y=8 and X={2, 3}, the candidates for the starting RO of the RO bundle of X=2 are {RO0, RO2, RO4, RO6}, and the candidates for the starting RO of the RO bundle of X=3 are {RO0, RO3}. Fig.12 The mapping of RO binding to UE_ID is indicated in .

[0118] Example 5:

[0119] like Fig.13 As shown, in the case of Y=4 and X={2, 4}, the candidates for the starting RO of the RO bundle of X=2 are {RO0, RO2}, and the starting RO of the RO bundle of X=4 is RO0. Fig.12 The mapping of RO binding to UE_ID is indicated in .

[0120] Method 2.2: Alternatively or additionally, the starting RO of the RO bundling may be explicitly configured through signaling.

[0121] Method 2.3: Alternatively or additionally, the starting RO of the RO bundling may be predefined as the first RO among the ROs mapped to a specific SSB.

[0122] For example, Fig.14 As shown, in the case of Y=8 and X=2, the starting RO is RO0. Fig.15 As another example shown, when Y=8 and X={2, 3}, the starting RO of both RO bundles is RO0.

[0123] III. Random Access Response Reception

[0124] The present disclosure also discloses how the BS processes these repetitions after the UE transmits multiple PRACH / Msg1 repetitions (including Msg1 scanning and SSB bundling). The following two methods are exemplary methods for processing Msg1 and generating Msg2 (random access response).

[0125] Method 3.1:

[0126] For RO bundling, the UE may transmit a preamble in one or more ROs of the RO bundle associated with the same SSB. A network such as a BS may detect the preamble in each RO of the RO bundle using single detection and joint detection (decrypted from signals from multiple ROs), and respond with Msg2(s) once the preamble is detected.

[0127] According to one embodiment, for one RO, at most one Msg2 is transmitted, including a traditional preamble and / or a feature-related preamble. If preambles are detected in multiple ROs, multiple corresponding Msg2s may be transmitted to improve the access success rate. For each PDCCH opportunity, the UE may detect Msg2(s) using multiple RA-RNTIs (Random Access-Radio Network Temporary Identifiers) associated with each RO bundled with the RO.

[0128] Exemplarily, the UE may start a RAR (Random Access Response) window at the first PDCCH opportunity after the first PRACH transmission. In addition, the RAR window may be configured to be longer based on repeated transmissions. Upon receiving Msg2 with a matching RAPID (Random Access Preamble Identifier), the UE may further stop the RAR window.

[0129] For a RO bundle of size X, suppose the RO is represented as RO x ,x=0,1,2,...,X-1, the network can detect RO successively 0 ,RO 1 ,RO 0 +RO 1 (Joint Detection), RO 2 ,RO 0 +RO 1 +RO 2 ,RO 3 ,RO 0 +RO 1 +RO 2 +RO 3 , ..., ROX-1 ,RO 0 +RO 1 +RO 2 +RO 3 +...+RO X-1 , including each independent RO and any combination of RO0 to ROx-1. The total number of detections is 2X-1. According to one embodiment, after single detection and joint detection, only one Msg2 is transmitted for each RO, including traditional preamble and / or feature-related preamble if necessary. For example, for RO2, if necessary, after detecting RO 2 and RO 0 +RO 1 +RO 2 Then Msg2 is transmitted.

[0130] The following is a discussion about a system with legacy UEs and UEs that support PRACH repetition. In the following example, the number of repetitions is 4, and there are five UEs (UE1, UE2, UE3, UE4, UE6) to transmit preambles in different ROs associated with the same SSB. UE1, UE2, UE3, UE4 are legacy UEs, and UE6 is a new UE that supports PRACH repetition to transmit PRACH in multiple ROs. The transmission of the preamble can be as follows: Fig.16 As shown, where:

[0131] -UE1 transmits the preamble in RO0 (PID=10);

[0132] -UE2 transmits a preamble in RO1 (PID=10);

[0133] -UE3 transmits the preamble (PID=10) in RO2;

[0134] -UE4 transmits a preamble (PID=11) in RO3; and

[0135] -UE6 transmits the preamble (PID=51) in RO0, RO1, RO2 and RO3.

[0136] First, the preamble can be detected in RO0, and the transmitted Msg2 should consist of Scrambling. If only preamble 10 is detected (such as Fig.16 If both preamble 10 (PID10) and 51 (PID51) are detected, Msg2(s) with RAPID 10 and 51 can be transmitted.

[0137] Then, the preamble can be detected in RO1 alone and / or jointly in RO0+RO1. Similarly, Msg2 should be composed of Scrambling. If preamble 10 and 51 are detected in RO1, and preamble 10 and 51 are jointly detected in RO0+RO1, Msg2 with RAPID 10 and 51 is transmitted. If preamble 10 is detected in RO1, and preamble 51 is jointly detected in RO0+RO1, Msg2 with RAPID 10 and 51 is transmitted. If preamble 10 is not detected in RO1, and preamble 10 and 51 are jointly detected in RO0+RO1, Msg2 with RAPID 51 is transmitted. Here, RAPID10 cannot be included in the transmitted Msg2 because preamble 10 belongs to the legacy RA resource, which cannot be detected by joint detection.

[0138] Then, the preamble can be detected in RO2 and the preamble can be detected jointly in RO0+RO1+RO2. Msg2 should be Similarly, the preamble is detected in RO3, and the preamble is jointly detected in RO0+RO1+RO2+RO3, and the corresponding Msg2 will be Scrambling. If any PID of a UE supporting PRACH repetition is jointly detected, the BS will transmit the corresponding Msg2 with the corresponding RAPID. Similarly, if the PID belongs to a legacy UE (not supporting PRACH repetition), the corresponding Msg2 will not be transmitted in the joint detection event.

[0139] Method 3.2:

[0140] Alternatively or additionally, for SSB bundling, the UE may transmit preambles in one or more ROs associated with different SSBs belonging to the SSB bundling, as long as the SS-RSRP of these SSBs is higher than rsrp-ThresholdSSB. If multiple preambles are detected in ROs associated with SSBs of the SSB bundling, the network (e.g., BS) may respond with one or more Msg2s, including a UL beam priority indication. Since the detected UL beams may need to be sorted and the priority information of the UL beams is included in Msg2, multiple Msg2s may be transmitted after all ROs are detected.

[0141] Exemplarily, the priority of the UL beam may be included in the Msg2 PDU (Protocol Data Unit) scrambled by RA-RNTI or the corresponding DCI1_0 (Downlink Control Information (DCI) format 1_0). For example, the reserved bits in the DCI1_0 scrambled by RA-RNTI may be used for UL beam priority indication.

[0142] "Search space" or "searchspace" refers to one or more areas in a downlink resource grid that can carry PDCCH. The UE can perform decoding (e.g., blind decoding) in these search spaces in an attempt to find PDCCH data (e.g., DCI). Exemplarily, the search space for Msg2 can be associated with an SSB, because the UE can detect Msg2 in the search space associated with the corresponding SSB, and the transmitted preamble is respectively associated with the SSB.

[0143] For example, if the UE transmits multiple preambles in ROs associated with different SSBs of an SSB bundle, the UE will detect DCI1_0 scrambled by RA-RNTI in the search spaces associated with these SSBs. Once the highest priority indication is received, the UE may stop detecting DCI1_0 in the remaining search spaces because the strongest UL beam has been found.

[0144] Exemplarily, the UE may start the RAR window at the first PDCCH opportunity after the last PRACH transmission, and the RAR window may be configured to be longer in consideration of repeated transmissions. Upon receiving the highest priority indication, the UE may stop the RAR window.

[0145] For example, Fig.17 As shown, an SSB bundle {SSB0, SSB1, SSB2, SSB3} is configured, and preamble {50, 51} is used for PRACH repetition. Assuming that the UE transmits three preambles in RO0, RO1, and RO3 associated with the SSB bundles SSB0, SSB1, and SSB3, the UE can detect Msg2 in the corresponding search spaces associated with SSB0, SSB1, and SSB3. As shown by the length of the arrow, the strongest UL beam found by the UE is the beam associated with SSB1.

[0146] for Fig.18In another example shown, an SSB bundle {SSB0, SSB1, SSB2, SSB3} is configured, and preamble {50, 51} is used for PRACH repetition. UE1 transmits PID50 in RO0 and RO1 associated with the SSB bundle SSB0 and SSB1, and UE2 transmits PID50 in RO2 and RO3 associated with the SSB bundle SSB2 and SSB3. UE1 can detect Msg2(s) in the corresponding search spaces associated with SSB0 and SSB1, and UE2 can detect Msg2(s) in the corresponding search spaces associated with SSB2 and SSB3. As indicated by the length of the arrows, the strongest UL beam found by UE1 is the beam associated with SSB1, and the strongest UL beam found by UE2 is the beam associated with SSB2.

[0147] IV. Fallback Operation

[0148] It is possible to fall back from the traditional RA process to the Msg1 repetition process, or from the Msg1 repetition process to the traditional RA process. For the Msg1 repetition process, it is possible to fall back from a lower repetition number to a higher repetition number, or from a higher repetition number to a lower repetition number.

[0149] Exemplarily, these fallback procedures may be actively triggered by the UE, for example, due to a change in RSRP referenced by a downlink path loss, or due to reaching a predefined number of failures, and so on.

[0150] Exemplarily, these fallback procedures may be indicated by the network, for example, by the BS, for example, via Msg2 or DCI.

[0151] Exemplarily, these fallback procedures may be applicable to both CBRA and CFRA procedures.

[0152] The above disclosed method / steps can be Figure 1 In addition, the hardware of the UE, BS and wireless communication system may include a non-temporary computer-readable storage medium storing one or more instructions. When the processor executes the one or more instructions, the wireless communication device performs the method / steps described above.

[0153] Various exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings to enable those of ordinary skill in the art to make and use the present disclosure. The present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific order and / or hierarchy of steps in the methods disclosed herein are merely exemplary methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be rearranged while remaining within the scope of the present disclosure. Therefore, it will be understood by those of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in an exemplary order, and the present disclosure is not limited to the specific order or hierarchy presented unless otherwise expressly stated.

[0154] The present disclosure is intended to cover any conceivable variation, use, combination or adaptation of the present disclosure that follows the general principles of the present disclosure, and includes knowledge and conventional technical means known in the art as well as content not disclosed in the present application.

[0155] It should be understood that the present disclosure is not limited to the exact construction or operation described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope of the present application, which is limited only by the appended claims.

Claims

1. A wireless communication method, comprising: At least one of the following configurations is set for the random access RA process: RA request repetition indicator, used to indicate whether the RA resource set is applicable to RA request repetition; RA request scan indicator, used to indicate whether the RA resource set is applicable to RA request scan; RA request repetition count, used to determine the number of times the RA request is repeated; RA request scan times, used to determine the number of RA request scans; a reference signal received power RSRP threshold for repetition, used to determine whether the RA request repetition is applicable to the RA process, or to determine which RA request repetition number to select from a plurality of RA request repetition numbers; Synchronous signal block SSB bundling configuration, used to determine the grouping of SSB; A random access channel RACH resource configuration, used to indicate a RACH resource used to transmit the RA request repetition or the RA request scan; The RA request repetition or the RA request scanning is performed according to the at least one configuration.

2. The method according to claim 1, wherein: When the RA request repetition indicator indicates that an RA resource set is applicable to the RA request repetition, the RA resource set is defined as applicable to uplink scheduled transmission repetition.

3. The method according to claim 1, wherein: Whether the RA resource set is applicable to the RA request repetition and uplink scheduled transmission repetition is configured separately by the RA request repetition indicator and another indicator.

4. The method according to claim 1, wherein: If the RA request repetition number and / or the RA request scanning number are configured, the RA resource set is defined as applicable to the RA request repetition.

5. The method according to claim 1, wherein: If the corresponding SSB bundling configuration is configured, the RA resource set is defined to be applicable for RA request repetition or scanning with different SSBs.

6. The method according to claim 1, wherein: If the RA request repetition indicator, the RA request scanning indicator, the RA request repetition number and / or the RA request scanning number are indicated or configured at the same time, the RA resource set is applicable to RA request repetition and scanning.

7. The method according to claim 1, wherein: Performing the RA request repetition or the RA request scanning according to the at least one configuration includes: transmitting the RA request in a plurality of consecutive RO bundles, wherein each RO bundle includes two or more consecutive SSBs, the consecutive SSBs having the same SSB identifier; or The RA request is transmitted in multiple SSB bundles, wherein each SSB bundle includes two or more consecutive SSBs, the consecutive SSBs having different SSB identifiers.

8. The method according to claim 1, wherein: The RA request repetition number and / or the RA request scan number are shared by all feature combinations in the bandwidth part BWP; or The RA request repetition number and / or the RA request scan number are configured separately for the feature combination in the BWP.

9. The method according to claim 1, wherein: The RA request repetition number and / or the RA request scanning number are configured for an RA resource set of contention-based random access or contention-free random access.

10. The method according to claim 1, wherein: The RA request repetition number and / or the RA request scanning number is indicated by a physical downlink control channel PDCCH order.

11. The method according to claim 10, wherein: The RA request repetition number and / or the RA request scanning number are indicated by reserved bits of DCI format 1_0.

12. The method according to claim 1, wherein: If a first RA resource set applicable to the RA request repetition and a second RA resource set not applicable to the RA request repetition are configured in one BWP at the same time, the UE or the BS understands that the RSRP threshold is configured.

13. The method according to claim 1, wherein: The RSRP threshold includes multiple threshold levels configured for multiple RA request repetition times, so that different repetition times are applied when different threshold levels are met.

14. The method according to claim 1, wherein: The RSRP threshold is configured for an RA resource set of contention-based random access or contention-free random access.

15. The method according to claim 1, wherein: The SSB bundling configuration indicates all transmitted SSBs in one SSB bundle, and the at least one configuration further includes an SSB bundling enable indicator.

16. The method according to claim 1, wherein: The SSB bundling configuration is shared by all feature combinations in the bandwidth part BWP; or The SSB bundling configuration is configured individually for the feature combination in the BWP.

17. The method according to claim 1, wherein: The RACH resource configuration indicates at least one of the following arrangements, wherein: The preambles for the RA request repetitions are arranged in two consecutive groups, each group including consecutive preambles associated with different numbers of Msg1 repetitions; The preambles for the RA request repetitions are arranged in two groups, each group includes preambles associated with different RA request repetition numbers, and the preambles associated with the same RA request repetition number in the two groups are arranged consecutively; The preambles used for the RA request repetition and scanning are arranged in two consecutive groups, each group including consecutive preambles associated with different RA request repetition numbers or RA request scanning; or Preambles for RA request repetition and scanning are arranged in two groups, each group includes preambles associated with different RA request repetition numbers or RA request scanning, preambles associated with the same RA request repetition number are arranged continuously in the two groups, and preambles for scanning are arranged continuously in the two groups.

18. A wireless communication method, comprising: The index of the starting physical random access channel opportunity RO is determined by: Determine the index of the starting RO = [UE_ID mod [floor (Y / X)]] × X, where Y is the total number of ROs associated with the SSB in the association period of the SSB to RO mapping, X is the number of random access RA request repetitions, and UE_ID is the UE index; Determine the index of the starting RO via signaling or a preset rule between the UE and the BS; or Determine the index of the starting RO as the first RO in the association period of SSB to RO mapping; The RA request is repeated by transmitting or receiving at X ROs starting from the index of the starting RO.

19. A wireless communication method, comprising: transmitting a random access RA request preamble in one or more physical random access channel opportunities RO associated with the same synchronization signal block SSB or associated with different SSBs; and In response to the RA request preamble transmitted by the UE, corresponding one or more RA responses are received.

20. The method according to claim 19, further comprising: After transmitting the first RA request preamble, starting a random access response RAR window at a first physical downlink control channel PDCCH opportunity, wherein the RAR window is expanded to respond to repeated transmissions of the RA request; Receiving a RA response with a matching random access preamble identifier RAPID stops the RAR window.

21. The method according to claim 19, wherein: The RA request preamble is transmitted in X ROs, which undergo 2X-1 detections by the BS to detect the RA request preamble transmitted from the X ROs individually and from their combination.

22. The method according to claim 21, wherein: X ROs including O x ,x=0,1,2,...,X-1,2X-1 detections include RO0, RO1, RO0+RO1 joint detection, RO2, RO0+RO1+RO2 joint detection, RO3, RO0+RO1+RO2+RO3 joint detection,...,RO X-1 、RO0+RO1+RO2+RO3+...+RO X-1 Joint testing.

23. The method according to claim 19, wherein: The corresponding one or more RA responses are scrambled by the corresponding RA_RNTI.

24. The method according to claim 19, wherein: In a case where the RA request preamble is transmitted in one or more ROs associated with different SSBs, receiving corresponding one or more RA responses includes: receiving the corresponding one or more RA responses including a UL beam priority indicator.

25. The method according to claim 24, wherein: The UL beam priority indicator is included in a RA response protocol data unit PDU or downlink control information DCI.

26. The method of claim 19, wherein: Receiving the corresponding one or more RA responses includes receiving the corresponding one or more RA responses from a search space corresponding to the RO used to transmit the RA request preamble.

27. The method according to claim 19, further comprising at least one of the following: Falling back from an RA process that is incompatible with RA repetition to an RA process that is compatible with RA repetition; Falling back from an RA process that is compatible with RA repetitions to an RA process that is incompatible with RA repetitions; Fall back from lower reps to higher reps; Work your way back down from the higher reps to the lower reps.

28. The method according to claim 27, wherein: The fallback is triggered by the UE or the BS.

29. The method according to claim 27, wherein: The fallback is triggered by the UE in response to a change in RSRP or reaching a predefined number of failures.

30. The method of claim 27, wherein: The fallback is triggered by the BS in response to signaling.

31. The method according to claim 30, wherein: The signaling includes a RA request response or a downlink control information DCI indication.

32. The method of claim 27, wherein: The fallback is performed under a contention-based random access procedure or a contention-free random access procedure.

33. A wireless communication method, comprising: receiving a random access RA request preamble in one or more physical random access channel opportunities RO associated with the same synchronization signal block SSB or associated with different SSBs; and In response to the RA request preamble received by the BS, corresponding one or more RA responses are transmitted.

34. The method of claim 33, wherein: After transmitting the first RA request preamble, at the first physical downlink control channel PDCCH opportunity, the corresponding one or more RA responses are received in the random access response RAR window, wherein the RAR window is expanded in response to the repeated transmission of the RA request, and a RA response with a matching random access preamble identifier RAPID is received, and the RAR window is stopped.

35. The method of claim 33, wherein: The RA request preamble is transmitted in X ROs, and the method further includes detecting the X ROs subjected to 2X-1 detections by the BS to detect RA request preambles transmitted individually from the X ROs and transmitted in combination from the X ROs.

36. The method of claim 33, wherein: X ROs including O x ,x=0,1,2,...,X-1,2X-1 detections include RO0, RO1, RO0+RO1 joint detection, RO2, RO0+RO1+RO2 joint detection, RO3, RO0+RO1+RO2+RO3 joint detection,...,RO X-1 、RO0+RO1+RO2+RO3+...+RO X-1 Joint testing.

37. The method of claim 33, further comprising: The corresponding one or more RA responses are scrambled by the corresponding RA_RNTI.

38. The method of claim 33, wherein: In a case where the RA request preamble is transmitted in one or more ROs associated with different SSBs, transmitting the corresponding one or more RA responses includes transmitting the corresponding one or more RA responses including a UL beam priority indicator.

39. The method of claim 38, wherein: The UL beam priority indicator is included in a RA response protocol data unit PDU or downlink control information DCI.

40. The method of claim 33, wherein: The corresponding one or more RA responses are searched by the UE in a search space corresponding to the RO used to transmit the RA request preamble.

41. The method of claim 33, further comprising at least one of the following: Falling back from an RA process that is incompatible with RA repetition to an RA process that is compatible with RA repetition; Falling back from an RA process that is compatible with RA repetitions to an RA process that is incompatible with RA repetitions; or Work your way back down from the higher reps to the lower reps.

42. The method according to claim 41, wherein: The fallback is triggered by the UE or the BS.

43. The method of claim 41, wherein: The fallback is triggered by the UE in response to a change in RSRP or reaching a predefined number of failures.

44. The method of claim 41, wherein: The fallback is triggered by the BS in response to signaling.

45. The method of claim 44, wherein: The signaling includes a RA request response or a downlink control information DCI (indication).

46. ​​The method of claim 41, wherein: The fallback is performed under a contention-based random access procedure or a contention-free random access procedure.

47. A wireless communication device, comprising a memory storing one or more programs and a processor electrically coupled to the memory, the processor being configured to execute the one or more programs to perform the method according to any one of claims 1 to 46.

48. A non-transitory computer-readable storage medium storing one or more programs, the one or more programs being configured to, when executed by a processor, cause the method of any one of claims 1 to 46 to be performed.

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