Random access methods, terminal and network side device

Abstract

The present application belongs to the technical field of communications. Disclosed are random access methods, a terminal and a network side device. A random access method of the embodiments of the present application comprises: a terminal executes a first operation, the first operation comprising at least one of the following: measuring at least one set of first synchronization signals amongst a plurality of sets of first synchronization signals; determining a transmission solution corresponding to random access related signals; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to random access related signals; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

Description

Random access method, terminal and network side device

[0001] Cross-reference

[0002] The present application claims priority from the Chinese patent application No. 2024109536272, filed on July 16, 2024, and entitled "Random access method, terminal and network side device", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application belongs to the field of communication technology, and specifically relates to a random access method, a terminal and a network side device. BACKGROUND

[0004] In a cell-free (or called large cell) massive multiple-input multiple-output (MIMO) system, a large number of base station antennas are distributed on a wide area, and terminals are also distributed on the wide area. These distributed base station antennas are called transmission reception points (TRPs). In theory, each terminal can communicate with each TRP, and a large number of geographically distributed TRPs can serve the terminal individually or collectively, i.e., a multi-TRP transmission scenario.

[0005] The cell-free system is expected to be applied to the next generation of indoor and hotspot coverage scenarios, such as smart factories, train stations, shopping centers, stadiums, subways, hospitals, community centers or university campuses, etc. In practice, the cell-free network in the hotspot area can be regarded as a super cell containing multiple TRPs, and the TRPs can implement cooperative transmission.

[0006] However, for the random access process, the related technology cannot support TRP switching or multi-TRP cooperation to complete the random access process in the cell-free system or other large cell multi-TRP system. Therefore, how to complete the random access process through switching between multiple TRPs or cooperative transmission of multiple TRPs in the cell-free system or other large cell multi-TRP system is a key problem to be discussed. SUMMARY

[0007] The embodiments of the present application provide a random access method, a terminal and a network side device, which can solve the problem of how to complete the random access process through switching between multiple TRPs or cooperative transmission of multiple TRPs in the cell-free system or other large cell multi-TRP system.

[0008] In a first aspect, a random access method is provided, comprising: performing, by a terminal, a first operation, the first operation comprising at least one of: measuring at least one of a plurality of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random procedure related first uplink signal; determining QCL information corresponding to the random access related signal; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0009] In a second aspect, a random access method is provided, comprising: performing, by a network side device, a second operation, the second operation comprising at least one of: transmitting a plurality of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random procedure related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of a random access related PDCCH resource; and determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0010] In a third aspect, a random access apparatus is provided, comprising: a processing module configured to perform a first operation, the first operation comprising at least one of: measuring at least one of a plurality of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random procedure related first uplink signal; determining QCL information corresponding to the random access related signal; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0011] In a fourth aspect, a random access apparatus is provided, comprising: a processing module configured to perform a second operation, the second operation comprising at least one of: transmitting a plurality of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random procedure related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of a random access related PDCCH resource; and determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0012] In a fifth aspect, a random access apparatus is provided, the apparatus being configured to perform the steps of the method of the first aspect, or to implement the steps of the method of the second aspect.

[0013] In a sixth aspect, a terminal is provided, which comprises a processor and a memory, the memory storing programs or instructions executable on the processor, and the programs or instructions, when executed by the processor, implement the steps of the method according to the first aspect.

[0014] In a seventh aspect, a terminal is provided, which comprises a processor and a communication interface, wherein the processor is configured to perform a first operation, and the first operation comprises at least one of the following: measuring at least one of a plurality of sets of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to a random access related signal; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0015] In an eighth aspect, a network side device is provided, which comprises a processor and a memory, the memory storing programs or instructions executable on the processor, and the programs or instructions, when executed by the processor, implement the steps of the method according to the first aspect.

[0016] In a ninth aspect, a network side device is provided, which comprises a processor and a communication interface, wherein the processor is configured to perform a second operation, and the second operation comprises at least one of the following: transmitting a plurality of sets of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random process related first uplink signal; determining or indicating QCL information corresponding to a random access related signal; determining or indicating related information of a random access related PDCCH resource; and determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0017] In a tenth aspect, a readable storage medium is provided, which stores programs or instructions, and the programs or instructions, when executed by a processor, implement the steps of the method according to the first aspect, or implement the steps of the method according to the second aspect.

[0018] In an eleventh aspect, a wireless communication system is provided, which comprises a terminal and a network side device, the terminal being configured to perform the steps of the method according to the first aspect, and the network side device being configured to perform the steps of the method according to the second aspect.

[0019] In a twelfth aspect, a chip is provided, which comprises a processor and a communication interface, the communication interface being coupled to the processor, and the processor being configured to execute programs or instructions, implement the method according to the first aspect, or implement the method according to the second aspect.

[0020] In a thirteenth aspect, a computer program / program product is provided, which is stored in a storage medium, and is executed by at least one processor to implement the method according to the first aspect, or to implement the method according to the second aspect.

[0021] In the embodiments of the present application, the terminal measures at least one set of first synchronization signals in multiple sets of first synchronization signals, determines a transmission scheme corresponding to the random access related signal, determines a time interval between the random access related first downlink signal and the random access related first uplink signal, determines QCL information corresponding to the random access related signal, determines related information of the random access related PDCCH resource, and determines a power control corresponding to the random access related second uplink signal. The loss reference signal is beneficial to improving the performance of random access in a cell-free or other large cell multi-TRP system. BRIEF DESCRIPTION OF DRAWINGS

[0022] FIG. 1 is a schematic diagram of a wireless communication system according to an embodiment of the present application;

[0023] FIG. 2 is a schematic diagram of a hierarchical cell-free network according to an embodiment of the present application;

[0024] FIG. 3 is a schematic flowchart of a random access method according to an embodiment of the present application;

[0025] FIG. 4 is a schematic flowchart of a random access method according to an embodiment of the present application;

[0026] FIG. 5 is a schematic structural diagram of a random access device according to an embodiment of the present application;

[0027] FIG. 6 is a schematic structural diagram of a random access device according to an embodiment of the present application;

[0028] FIG. 7 is a schematic structural diagram of a communication device according to an embodiment of the present application;

[0029] FIG. 8 is a schematic structural diagram of a terminal according to an embodiment of the present application;

[0030] FIG. 9 is a schematic structural diagram of a network side device according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0032] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, not limited in number; for example, the first object can be one or more. Furthermore, "or" in this application indicates at least one of the connected objects. For example, the scope of protection for "A or B" covers at least three scenarios: Scenario 1: including A but not B; Scenario 2: including B but not A; Scenario 3: including both A and B. In addition, the terms "A and / or B," "at least one of A and B," and "at least one of A or B" also cover at least the above three scenarios. The character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0033] The term "instruction" in this application can be either a direct instruction (or explicit instruction) or an indirect instruction (or implicit instruction). A direct instruction can be understood as one in which the sender explicitly informs the receiver of specific information, the operation to be performed, or the requested result, etc., in the instruction sent. An indirect instruction can be understood as one in which the receiver determines the corresponding information based on the instruction sent by the sender, or makes a judgment and determines the operation to be performed or the requested result, etc., based on the judgment result.

[0034] It is worth noting that the technology described in the embodiments of the present application is not limited to Long Term Evolution (LTE) / LTE-Advanced (LTE-A) systems, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency-Division Multiple Access (SC-FDMA) or other systems. The terms "system" and "network" in the embodiments of the present application are often used interchangeably, and the described technology can be used in the above-mentioned systems and radio technologies, as well as in other systems and radio technologies. The following description describes a New Radio (NR) system for example purposes, and NR terminology is used in most of the following description, but these technologies can also be applied to systems other than NR systems, such as 6th Generation (6G) communication systems. th

[0035] ​FIG. 1 shows a block diagram of a wireless communication system to which embodiments of the present application can be applied. The wireless communication system includes a terminal 11 and a network-side device 12. The terminal 11 can be a terminal-side device such as a mobile phone, a Tablet Personal Computer, a Laptop Computer, a notebook computer, a Personal Digital Assistant (PDA), a palmtop computer, a netbook, an Ultra-mobile Personal Computer (UMPC), a Mobile Internet Device (MID), an Augmented Reality (AR) device, a Virtual Reality (VR) device, a robot, a wearable device, a flight vehicle, a Vehicle User Equipment (VUE), a shipboard device, a Pedestrian User Equipment (PUE), a smart home (a home device with a wireless communication function such as a refrigerator, a television, a washing machine, or furniture), a game console, a Personal Computer (PC), a kiosk, or a self-service machine. The wearable device includes a smart watch, a smart bracelet, a smart earphone, smart glasses, smart jewelry (a smart bracelet, a smart necklace, a smart ring, a smart necklace, a smart anklet, a smart necklace, etc.), a smart wristband, smart clothes, etc. The vehicle-mounted device can also be referred to as a vehicle-mounted terminal, a vehicle-mounted controller, a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip, or a vehicle-mounted unit, etc. It should be noted that the specific type of the terminal 11 is not limited in the embodiments of the present application. The network-side device 12 can include an access network device or a core network device. The access network device can also be referred to as a Radio Access Network (RAN) device, a radio access network function, or a radio access network unit. The access network device can include a base station, a Wireless Local Area Network (WLAN) Access Point (AP), or a Wireless Fidelity (WiFi) node, etc.The base station can be referred to as a Node B (NB), an evolved Node B (eNB), a next generation Node B (gNB), a New Radio Node B (NR Node B), an access point, a relay station (RBS), a serving base station (SBS), a base transceiver station (BTS), a radio base station, a radio transceiver, a basic service set (BSS), an extended service set (ESS), a home Node B (HNB), a home evolved Node B, a transmit / receive point (TRP), or some other suitable terminology in the art, so long as 5 the base station is capable of achieving the same technical effect, and the base station is not limited to a specific technical term. It should be noted that in the embodiments of the present application, only the base station in the NR system is taken as an example for introduction, and the specific type of the base station is not limited.

[0036] In a traditional centralized large-scale Multiple-Input Multiple-Output (MIMO) network, all antenna units are deployed on a macro base station. In contrast, in a cell-free network, antenna units are deployed in a distributed manner in TRPs at different locations, thereby obtaining better diversity gain. From the perspective of network deployment, there are two typical network architectures for a cell-free network.

[0037] 1. Single-tier cell-free network

[0038] All TRPs are deployed in the same tier, and each TRP is directly connected to a central processor (CPU) through a front-haul link for data transmission and resource allocation. The TRP is responsible for transmitting signals to and receiving signals from the terminal, while the CPU is responsible for allocating, combining, precoding and processing data from different TRPs, and updating the TRP cluster serving different terminals.

[0039] 2. Hierarchical cell-free network

[0040] As shown in FIG. 2, the first layer can be used to implement the initial access and mobility management of the terminal, complete the low-delay control signaling exchange between the terminal and the network, and provide high coverage performance. For example, the first layer network can be a hyper cell (e.g., a macro TRP) based on single frequency network (SFN) technology or dynamic site selection (DPS) technology, or a wide coverage cell based on low frequency band communication (e.g., using existing 2G / 3G infrastructure or spectrum resources), or a satellite / high altitude platform station (HAPS) cell in satellite communication.

[0041] As shown in FIG. 2, the second layer can implement high-speed data transmission by dynamically selecting one or more transmission nodes (e.g., small TRPs) for each terminal to perform MIMO transmission, which can obtain higher spatial multiplexing gain and provide higher data transmission rate. For example, the second layer network can use a non-SFN mode, or use a higher frequency band than the first layer network, or use a low earth orbit satellite in satellite communication.

[0042] The synchronization signal / reference signal of the first layer network node can be associated with the synchronization signal / reference signal of the second layer network node in the same area. For example, the first layer network can use a wide beam reference signal to maintain a stable connection of the terminal, and the second layer network can use multiple narrow beam reference signals related to the wide beam to implement high-speed transmission of the terminal.

[0043] In the current NR system, the random access procedure is completed on the same TRP, i.e., the related uplink and downlink messages of the random access are transmitted and received between the terminal and the same TRP. However, for a cell-free system, it can be considered to transmit the related uplink and downlink messages of the random access procedure on multiple TRPs. For example, for a hierarchical structure cell-free system, switching can be performed between the macro TRP and the small TRP, so that part of the steps of the random access procedure are completed on the small TRP; for example, for a single layer or hierarchical structure cell-free, when the terminal moves at a high speed, switching can also be performed between multiple TRPs, so that the terminal transmits on the optimal TRP. Of course, in some cases, multiple TRPs can also be used to transmit and receive random access related messages.

[0044] For the above-mentioned cell-free random access procedure, the related art cannot support the completion of the random access procedure on multiple TRPs, for example, lacks related mechanisms to support switching between TRPs, changes in transmission configuration indicator (TCI) / quasi-co-location (QCL) indication information of uplink and downlink signals, power control corresponding to different TRPs, etc. In addition, the QCL assumption of the physical downlink control channel (PDCCH) resource on the common search space in the NR system is defined semi-statically according to the search space, which is relatively fixed and cannot be dynamically changed, resulting in limited use efficiency and system capacity.

[0045] The random access method provided by the embodiments of the present application will be described in detail below in combination with the accompanying drawings and some embodiments and application scenarios.

[0046] As shown in FIG. 3, the present application provides a random access method 300, which can be executed by a terminal, in other words, the method can be executed by software or hardware installed in the terminal, and the method includes the following steps.

[0047] S302: The terminal performs a first operation, and the first operation includes at least one of the following: 1) measuring at least one set of first synchronization signals in multiple sets of first synchronization signals; 2) determining a transmission scheme corresponding to a random access related signal; 3) determining a time interval between a random access related first downlink signal and a random process related first uplink signal; 4) determining QCL information corresponding to a random access related signal; 5) determining related information of a random access related PDCCH resource; 6) determining a power control corresponding to a loss reference signal of a random access related second uplink signal.

[0048] In one embodiment, the first synchronization signal can be a synchronization signal and PBCH block (SSB); the first synchronization signal can also be other signals, such as a channel state information-reference signal (CSI-RS), a tracking reference signal (TRS), etc.

[0049] Optionally, at least one set of first synchronization signals in multiple sets of first synchronization signals corresponds to one TRP or one TRP group, for example, each set of SSB corresponds to one TRP or TRP group.

[0050] The embodiment is beneficial for the terminal to determine the TRP corresponding to the random access according to the measurement result of the first synchronization signal, for example, to determine through which TRP or TRPs or TRP group to perform the random access, and to complete the random access process through switching between multiple TRPs or cooperative transmission of multiple TRPs in a cell-free system or other large-cell multi-TRP system, thereby improving the performance of the random access.

[0051] In one embodiment, determining the transmission scheme corresponding to the random access related signal includes: 1) determining the transmission mode corresponding to the random access related signal, for example, whether to perform transmission of the random access related signal based on a single-TRP (STRP) mode or a multi-TRP (MTRP) mode; and 2) determining the TRP information corresponding to the random access related signal, for example, including a TRP identifier, a number of TRPs, and the like.

[0052] The embodiment is beneficial for the terminal to determine whether to perform transmission based on the STRP mode or the MTRP mode, and to determine the TRP identifier, the number of TRPs, and the like corresponding to the random access related signal, and to complete the random access process through switching between multiple TRPs or cooperative transmission of multiple TRPs in a cell-free system or other large-cell multi-TRP system, thereby improving the performance of the random access.

[0053] In one embodiment, the first downlink signal includes a random access message two (Msg2), and the first uplink signal includes a random access message three (Msg3). Msgx appearing in the present application refers to a random access message x. For example, Msg1 represents a random access message one, and MsgA represents a random access message A, which will not be described below.

[0054] The embodiment is beneficial for the base station and the terminal to have more sufficient time to cope with adjustment of the transmission mode or the TRP, to complete the random access process through switching between multiple TRPs or cooperative transmission of multiple TRPs in a cell-free system or other large-cell multi-TRP system, and to improve the performance of the random access.

[0055] For the case of switching the transmission mode or the TRP in the random access process, the switching of the transmission mode or the TRP will cause a change in the QCL assumption, including transmission of the uplink message and the downlink message. In one embodiment, by determining the QCL information corresponding to the random access related signal, the correct reception of the random access related signal is facilitated, and the performance of the random access is improved.

[0056] In an embodiment, the information related to the random access related PDCCH resource includes, for example: a mapping relationship between the random access related PDCCH resource and at least one set of first synchronization signals; and an enabling condition of the random access related PDCCH resource. This embodiment determines the information related to the random access related PDCCH resource, and in a cell-free system or other large-cell multi-TRP system, the random access process can be completed through switching between multiple TRPs or cooperative transmission of multiple TRPs, which is conducive to correct transmission of the random access related PDCCH and improves the performance of random access.

[0057] In an embodiment, the second uplink signal includes at least one of: a physical random access channel (PRACH), Msg1, Msg3, MsgA, a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), a sounding reference signal (SRS), a configuration grant physical uplink shared channel (CG PUSCH), a wake-up-signaling (WUS), a tracking reference signal (TRS) for uplink, and a demodulation reference signal (DMRS).

[0058] This embodiment determines the power control corresponding to the loss reference signal of the random access related second uplink signal, which is conducive to power control of the second uplink signal, and in a cell-free system or other large-cell multi-TRP system, the random access process can be completed through switching between multiple TRPs or cooperative transmission of multiple TRPs, thereby improving the success rate of transmission of the second uplink signal.

[0059] The random access method provided by the embodiments of the present application is as follows: a terminal measures at least one set of first synchronization signals in multiple sets of first synchronization signals; determines a transmission scheme corresponding to a random access related signal; determines a time interval between a random access related first downlink signal and a random access related first uplink signal; determines QCL information corresponding to the random access related signal; determines related information of a random access related PDCCH resource; and determines a loss reference signal corresponding to power control of a random access related second uplink signal, which is beneficial to improving the performance of random access in a cell-free or other large-cell multi-TRP system.

[0060] For a cell-free system or other large-cell multi-TRP system, in order to more flexibly and efficiently complete random access and improve the performance of random access, the embodiments of the present application propose related enhanced design schemes to support the completion of the random access process on multiple TRPs, including the case of switching between TRPs and the case of multiple TRPs cooperating to transmit and receive random access related signals, thereby improving the performance, efficiency and capacity of random access. Meanwhile, the embodiments of the present application also optimize the QCL assumption of other resources such as PDCCH resources on the common search space, improve the use efficiency and system capacity, and reduce the detection complexity and power consumption.

[0061] Through the schemes of the embodiments of the present application, for a cell-free or other large-cell multi-TRP system, the characteristics of cell-free and the corresponding deployment architecture can be fully utilized, so that different TRPs or multiple TRPs can be more flexibly used for random access and the use of common resources, which can effectively improve the performance of random access resources and the use efficiency of common resources, improve the system capacity, and reduce the detection complexity and power consumption of related common channel resources.

[0062] The first operation performed by the terminal and related schemes will be described in detail in the following embodiments.

[0063] In one embodiment, the first operation performed by the terminal includes measuring at least one set of first synchronization signals in multiple sets of first synchronization signals, and the multiple sets of first synchronization signals are different in at least one of the following:

[0064] 1) corresponding transmission resources, including at least one of the following: period, time window, frequency domain resource, transmission occasion (occasion).

[0065] The first synchronization signal can be SSB, CSI-RS or TRS, and the following embodiments will take SSB as an example to introduce the first synchronization signal.

[0066] For example, the first periodic SSB corresponds to a macro TRP, and the second periodic (larger than the first periodic) SSB corresponds to a small TRP.

[0067] For example, different TRPs correspond to different frequency domain positions or different SSB frequency domain offsets.

[0068] For example, different TRPs correspond to different transmission occasions or transmission occasion groups in the same SSB burst, such as transmission occasion #1 and transmission occasion #2 (which can be understood as transmission occasion group #1) in the SSB burst correspond to TRP1, and transmission occasion #3 and transmission occasion #4 (which can be understood as transmission occasion group #2) correspond to TRP2.

[0069] 2) Corresponding first synchronization signal group.

[0070] For example, this embodiment can default the index set, that is, a specific range of SSB indexes belong to the corresponding SSB group, such as SSB#1 and SSB#2 correspond to TRP1, and SSB#3 and SSB#4 correspond to TRP2.

[0071] At this time, for SSBs on different transmission resources, the association between SSBs and TRPs can be agreed by default. For example, SSBs transmitted on certain frequency domain resources correspond to a certain TRP by default. As long as the terminal detects SSBs on different transmission resources, it can be considered that the SSBs come from different TRPs. When the terminal performs SSB detection, it can select the optimal SSB according to the measurement result of the SSB, that is, determine the optimal TRP or multiple TRPs.

[0072] For different SSB groups, for example, SSB group 1 includes {SSB0, SSB1} corresponding to TRP1, and SSB group 2 includes {SSB2, SSB3, SSB4} corresponding to TRP2 (the number of SSBs corresponding to different TRPs can also be different). In this way, the terminal is clear about the association between SSBs and TRPs.

[0073] In one embodiment, the multiple sets of first synchronization signals and physical random access channel (PRACH) resources satisfy at least one of the following:

[0074] 1) At least two sets of first synchronization signals in the multiple sets of first synchronization signals correspond to the same PRACH resource.

[0075] For the uplink STRP case, different TRPs can correspond to the same PRACH resource, for example, different SSB groups correspond to the same PRACH resource, and each SSB group can correspond to a TRP.

[0076] 2) Each of the multiple sets of first synchronization signals corresponds to a random access occasion (RO) group, and the RO group corresponds to the PRACH resource.

[0077] 3) Each of the multiple sets of first synchronization signals corresponds to a preamble group, and the preamble group corresponds to the PRACH resource.

[0078] For 2) or 3) above, for the uplink MTRP case, for example, each SSB group can correspond to a TRP, each TRP corresponds to an RO group, and the RO groups can be the same in the frequency domain or the same in the time domain; for another example, there is an association relationship between the RO groups; for another example, each SSB group can correspond to a TRP, each TRP corresponds to a preamble group, and there is an association relationship between the preamble groups.

[0079] 4) The mapping relationship between at least two of the multiple sets of first synchronization signals and the PRACH resource is configured in the same PRACH resource configuration signaling.

[0080] For example, multiple SSB-to-PRACH resource association configurations are introduced in the PRACH common configuration (PRACH config common) parameter, so that different SSB-to-PRACH resource association relationships, such as the mapping ratio of the two, can be configured for different corresponding TRPs.

[0081] In one embodiment, the first operation performed by the terminal includes determining a transmission scheme corresponding to the random access related signal, and the determination of the transmission scheme corresponding to the random access related signal includes determining the transmission scheme by at least one of the following:

[0082] 1) Broadcast message.

[0083] 2) First synchronization signal.

[0084] 3) PRACH resource.

[0085] 4) PRACH resource configuration signaling.

[0086] 5) First frequency domain resource.

[0087] For example, the terminal determines whether the random access related signal is transmitted based on the STRP mode or the MTRP mode or determines the TRP that transmits the random access related signal, including the TRP identifier, the number of TRPs, etc., by using the information of at least one of the above 1) to 5).

[0088] In one embodiment, when determining the transmission scheme corresponding to the random access related signal through the broadcast message, the broadcast message comprises at least one of:

[0089] 1) Master Information Block (MIB).

[0090] 2) System Information Blocks (SIB), e.g. SIB1.

[0091] 3) Layer One payload (L1-payload).

[0092] In one embodiment, when determining the transmission scheme corresponding to the random access related signal through the first synchronization signal, the transmission scheme is determined through at least one of:

[0093] 1) the sequence of Demodulation Reference Signal (DMRS) in the first synchronization signal, e.g. the sequence of DMRS implies the transmission mode (or the number of TRPs or the identity of TRPs) in the sequence generation.

[0094] 2) the time domain offset of DMRS in the first synchronization signal.

[0095] 3) the frequency domain offset of DMRS in the first synchronization signal.

[0096] 4) the sequence generation way of synchronization sequence in the first synchronization signal, e.g. the sequence generation of Primary Synchronization Signal (PSS) and / or Secondary Synchronization Signal (SSS) implies the transmission mode (or the number of TRPs or the identity of TRPs).

[0097] 5) the length of synchronization sequence in the first synchronization signal.

[0098] 6) the number of synchronization sequence in the first synchronization signal.

[0099] 7) the transmission resource relationship between synchronization sequences in the first synchronization signal, e.g. the time domain interval between PSS and SSS.

[0100] 8) the time-frequency resource relationship between multiple first synchronization signals, e.g. the time domain or frequency domain interval between SSBs, such as corresponding to a certain transmission mode if a certain condition or pattern is met.

[0101] 9) The first synchronization signal exists in a certain time domain or frequency domain window, for example, if two SSBs (corresponding to two different TRPs respectively) appear in a predetermined frequency domain window, it is the MTRP transmission mode.

[0102] In one embodiment, when the transmission scheme corresponding to the random access related signal is determined through the PRACH resource, the transmission scheme is determined through at least one of the following:

[0103] 1) The length of the preamble corresponding to the PRACH resource, for example, different preamble lengths correspond to different transmission modes.

[0104] 2) The format of the preamble corresponding to the PRACH resource.

[0105] 3) The number of groups of the preamble corresponding to the PRACH resource, for example, different numbers of groups correspond to different numbers of TRPs.

[0106] 4) The relationship between the ROs or RO groups corresponding to the PRACH resource, such as the time-frequency and / or frequency domain resource relationship between the ROs.

[0107] 5) The number of RO groups corresponding to the PRACH resource, for example, different numbers of RO groups correspond to different numbers of TRPs.

[0108] In one embodiment, when the transmission scheme corresponding to the random access related signal is determined through the PRACH resource configuration signaling, the transmission scheme is determined through at least one of the following:

[0109] 1) The indication of the PRACH resource configuration signaling, wherein the transmission scheme is explicitly indicated in the PRACH resource configuration signaling.

[0110] 2) The PRACH resource configuration table used to configure the PRACH resource, wherein the transmission scheme is defined in the PRACH resource configuration table.

[0111] In one embodiment, when the transmission scheme corresponding to the random access related signal is determined through the first frequency domain resource, the transmission scheme is determined through at least one of the following: frequency band; Band Width Part (BWP); specific frequency resource; sub-band; carrier; carrier group; serving cell.

[0112] For example, in this embodiment, the number of the first frequency resources occupied by the first synchronization signal is used to determine the transmission scheme corresponding to the random access related signal.

[0113] In one embodiment, the first operation performed by the terminal includes determining a transmission scheme corresponding to the random access related signal, and the determining the transmission scheme corresponding to the random access related signal includes, in the case of reaching a first condition, determining or switching a transmission scheme corresponding to a random access related third uplink signal; wherein the first condition includes that the random access related third uplink signal satisfies at least one of the following:

[0114] 1) The number of retransmissions of the random access related third uplink signal reaches a first number. For example, the number of retransmissions of the third uplink signal on the PRACH and / or PUSCH resource associated with one or a group of SSBs (or one or a group of TRPs) reaches a first number.

[0115] 2) The transmission power of the random access related third uplink signal reaches a first power. For example, the transmission power of the third uplink signal on the PRACH and / or PUSCH resource associated with one or a group of SSBs (or one or a group of TRPs) reaches a first power.

[0116] 3) The detection time of the response message of the random access related third uplink signal reaches a first time.

[0117] The third uplink signal of various embodiments of the present application includes, for example, Msg1, MsgA, RACH-less PUSCH, etc.

[0118] In one embodiment, the first operation performed by the terminal includes determining a transmission scheme corresponding to the random access related signal, and the determining the transmission scheme corresponding to the random access related signal includes determining or switching a transmission scheme corresponding to a random access related second downlink signal by at least one of the following:

[0119] 1) The resource corresponding to the random access related third uplink signal, for example, the PRACH resource or the RACH-less PUSCH resource. For example, the preamble or the RO or the PUSCH resource corresponding to the Msg1 or the MsgA sent by the terminal, or the RACH-less PUSCH resource sent by the terminal.

[0120] For example, the terminal sends the preamble on two specific ROs, which implicitly informs the network side to subsequently transmit the Msg2 or the MsgB in the MTRP mode.

[0121] Wherein the second downlink signal can be Msg2, MsgB, or the response message of the RACH-less PUSCH, and the second downlink signal can also be the same as the first downlink signal.

[0122] 2) Downlink Control Information (DCI) scheduling the random access related second downlink signal. For example, DCI scheduling Msg2 or MsgB or RACH-less PUSCH feedback message.

[0123] 3) Radio Resource Control (RRC) signaling, such as handover command signaling; Beam failure recovery (BFR) signaling; and so on.

[0124] 4) First reference signal, such as WUS.

[0125] The embodiment can also determine or switch the transmission scheme corresponding to the random access related second downlink signal through system messages (such as SIB1).

[0126] The DCI or RRC signaling in the embodiment can also be referred to as first signaling, and the first signaling can be used to indicate at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The above-mentioned indicated information is associated with the TRP.

[0127] In one embodiment, the first operation performed by the terminal includes determining the transmission scheme corresponding to the random access related signal, and the determining the transmission scheme corresponding to the random access related signal includes determining or switching the transmission scheme corresponding to the random access related fourth uplink signal (such as Msg3) through at least one of the following:

[0128] 1) Default agreement mode, which agrees that the transmission scheme corresponding to the random access related fourth uplink signal is the same as the transmission scheme corresponding to the random access related third uplink signal.

[0129] 2) The number of retransmissions of the random access related fourth uplink signal.

[0130] 3) Indication in the random access related second downlink signal.

[0131] The fourth uplink signal in the embodiment can be Msg3, and the fourth uplink signal can also be the same as the first uplink signal. The third uplink signal includes, for example, Msg1; MsgA; RACH-less PUSCH.

[0132] The second downlink signal can be, for example, a random access response (RAR), and the RAR indicates at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The indicated information is associated with a TRP.

[0133] In one embodiment, the first operation performed by the terminal includes determining a transmission scheme corresponding to the random access related signal, and the determining the transmission scheme corresponding to the random access related signal includes determining or switching, by at least one of the following, a transmission scheme corresponding to the random access related third downlink signal (such as Msg4):

[0134] 1) a resource corresponding to the random access related third uplink signal. The third uplink signal includes, for example, Msg1; MsgA; RACH-less PUSCH.

[0135] 2) DCI scheduling the random access related second downlink signal. The second downlink signal can be, for example, a response message of Msg2; MsgB; RACH-less PUSCH.

[0136] 3) RRC signaling.

[0137] 4) a first reference signal, such as WUS.

[0138] 5) a default agreement mode, which agrees that the transmission scheme corresponding to the random access related third downlink signal is the same as the transmission scheme corresponding to the random access related second downlink signal.

[0139] 6) a request or indication in the random access related fourth uplink signal.

[0140] 7) DCI scheduling the random access related third downlink signal, and the DCI can indicate at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The indicated information is associated with a TRP.

[0141] In one embodiment, the first operation performed by the terminal includes determining a time interval between the random access related first downlink signal and the random process related first uplink signal, and the determining the time interval between the random access related first downlink signal and the random process related first uplink signal (for example, between Msg2 and Msg3) includes determining the time interval based on at least one of the following:

[0142] 1) a predefined time interval.

[0143] 2) A predefined rule, such as, an agreement that for a Msg3 transmitted after a TRP or QCL or TCI switching, the time interval between the scheduling DCI or the scheduled RAR or fallback RAR and the Msg3 PUSCH is not less than a certain or a set of network defined values.

[0144] This embodiment enables the base station and the terminal to have more sufficient time to cope with the adjustment of the transmission mode or the TRP, so as to improve the performance of the random access by determining the time interval between the first downlink signal and the first uplink signal.

[0145] In one embodiment, at least one of the QCL corresponding to the random access related signal and the power control of the random access related second uplink signal corresponding to the path loss reference signal is determined by one of the following:

[0146] 1) The reporting or recommendation of Msg3, for example, the terminal reports or recommends the DCI scheduling Msg4 or the QCL assumption of Msg4 through Msg3.

[0147] 2) The reporting or recommendation of MsgA PUSCH, for example, the terminal reports or recommends the DCI scheduling MsgB or the QCL assumption of MsgB through MsgA PUSCH.

[0148] 3) PRACH resource, for example, the terminal requests or indicates or recommends the QCL assumption of a specific subsequent one or more signal transmissions through transmission on a specific PRACH resource.

[0149] 4) WUS resource, for example, the terminal requests or indicates or recommends the QCL assumption of a specific subsequent one or more signal transmissions through transmission on a specific WUS resource.

[0150] 5) Indication of the second signaling; wherein the second signaling includes at least one of the following: RAR or fallback RAR; DCI scheduling RAR or fallback RAR; DCI scheduling Msg4; Msg4; system message; first media access control control element (MAC-CE) signaling.

[0151] The second signaling carries the following first information associated with (or used to represent) QCL: TRP index; SSB information (such as index, group index, transmission resource index); preamble information (such as index, group index); PUSCH information; RO information (such as index, group index).

[0152] In an embodiment, the second signaling satisfies at least one of the following relationships with a first Radio Network Temporary Identity (RNTI):

[0153] 1) A message in which the second signaling is located is scrambled by the first RNTI.

[0154] 2) A Cyclic Redundancy Check (CRC) of a message in which the second signaling is located is scrambled by the first RNTI.

[0155] In an embodiment, the related information of the random access related PDCCH resource includes at least one of the following:

[0156] 1) A mapping relationship between the random access related PDCCH resource and at least one set of first synchronization signals.

[0157] The mapping relationship includes that one or a group of TRPs or SSBs and PDCCH resources have a mapping relationship; and the same PDCCH resource can be associated with different SSBs or different SSB groups. The above-mentioned one or a group of TRPs or SSBs and PDCCH resources have a mapping relationship, which can include one of the following: an SSB or a TRP group and the PDCCH specific resource (such as one or more MOs or MOs within one or more windows) have a one-to-one correspondence; an SSB or a TRP and the PDCCH specific resource (such as one or more MOs or MOs within one or more windows) have a one-to-one correspondence.

[0158] 2) An enabling condition of the random access related PDCCH resource.

[0159] For example, the PDCCH resource is enabled by third signaling, and the third signaling can be in the form of a bitmap to enable the PDCCH resource. At this time, the enabling of the PDCCH resource can also be understood as the enabling of the TRP.

[0160] In an embodiment, the random access related PDCCH resource is a PDCCH resource corresponding to one of the following: 1) one or more monitoring occasions (MOs); 2) MOs within one or more time windows; 3) a resource element group (REG); 4) a search space; 5) a specific control channel element (CCE); and 6) a specific aggregation level (AL).

[0161] To make the random access method provided by the embodiments of the present application more specific, the following will be described in combination with several specific embodiments.

[0162] The TRP or TRP group in the present application can also be a TRP or TRP group associated with a certain specific signal, or a TRP or TRP group associated with a certain or a certain or a certain group of reference signals. The TRP can also be generalized as one or a group of repeaters, timing advance groups (TAGs), cells (such as non-terrestrial networks NTN, small cells), integrated access and backhaul (IAB), QCL, TCI state, beam, or other signal-associated transmission units under certain specific purposes. In addition, the TRP described in the present application can be replaced by the above-mentioned generalized objects, or characterized by the above-mentioned generalized objects, or the above-mentioned generalized objects can also be used as the identification information of the TRP.

[0163] The SSB in the present application can also be referred to as any module containing at least one of the synchronization signal, the broadcast signal, the broadcast channel (PBCH), the other system message downlink broadcast channel, and the control channel thereof.

[0164] Embodiment one

[0165] In this embodiment, the terminal determines the transmission scheme before initiating the RACH, and the transmission scheme includes the transmission mode and / or TRP information (which can be understood as semi-static determination).

[0166] The first case is that the TRP corresponding to the transmission of the random access related signal has been determined before the terminal initiates the random access. For example, which TRP is used for random access, or which several TRPs are used for random access, including the transmission mode (such as TDM, FDM, SDM, SFN, etc. MTRP transmission mode) when transmitting based on multiple TRPs. This helps the terminal to select the optimal TRP for random access, thereby improving the performance, capacity and efficiency of random access, reducing power consumption and interference between users.

[0167] In the initial access stage, the terminal first performs detection on the downlink signal such as SSB. At this time, since there is no prior information, if the terminal needs to identify different TRPs, the SSB can be used to implicitly correspond to different TRPs.

[0168] In some embodiments, the network side configures multiple sets of SSBs (such as different SSBs associated with different TRPs), and the multiple sets of SSBs are different in at least one of the following:

[0169] 1) Corresponding transmission resources, which include at least one of the following: period, time window, frequency domain resources, and transmission occasion.

[0170] For example, for stratified cell-free systems, the first-cycle SSB corresponds to the macro TRP, and the second-cycle (greater than the first-cycle) SSB corresponds to the small TRP.

[0171] For example, different TRPs correspond to different frequency domain positions or different SSB frequency domain offsets.

[0172] For example, different TRPs correspond to different transmission timings or transmission timing groups within the same SSB cluster (SSB burst). For instance, transmission timing #1 and transmission timing #2 (which can be understood as transmission timing group #1) in an SSB burst correspond to TRP1, while transmission timing #3 and transmission timing #4 (which can be understood as transmission timing group #2) correspond to TRP2.

[0173] 2) The corresponding SSB group.

[0174] For example, this embodiment can default to a set of indexes, that is, a specific range of SSB indexes belong to the corresponding SSB group, such as SSB#1 and SSB#2 corresponding to TRP1, and SSB#3 and SSB#4 corresponding to TRP2.

[0175] At this point, the association between SSBs and TRPs can be agreed upon by default for different transmission resources. For example, SSBs transmitted on certain frequency domain resources may correspond to a certain TRP by default. As long as the terminal detects SSBs on different transmission resources, it can assume they originate from different TRPs. When the terminal performs SSB detection, it can select the optimal SSB based on the SSB measurement results, thus determining the optimal TRP, or multiple TRPs.

[0176] For different SSB groups, for example, SSB group 1 includes {SSB0, SSB1} corresponding to TRP1; SSB group 2 includes {SSB2, SSB3, SSB4} corresponding to TRP2 (the number of SSBs corresponding to different TRPs can also be different). In this way, the terminal can clearly understand the association between SSBs and TRPs.

[0177] When supporting different TRPs or TRP groups, assuming there is no interference between TRPs or TRP groups, the same PRACH resources can be used for different TRPs, thereby improving the utilization of PRACH resources. The following is an example.

[0178] In some embodiments, different or different groups of SSB signals or TRPs can be independently mapped to the same PRACH resource.

[0179] For example, {SSB0, SSB1} in SSB group 1 correspond to TRP1; {SSB2, SSB3, SSB4} in SSB group 2 correspond to TRP2 (the number of SSBs corresponding to different TRPs can also be different). SSB group 1 and SSB group 2 can be associated with the same set of PRACH resources.

[0180] As a sub-embodiment of the above embodiment, the mapping of different SSBs or SSB sets to PRACH resources can be configured in the same PRACH resource configuration.

[0181] For example, introduce multiple SSB to RACH resource association configurations in the PRACH config common parameter, so that different SSB to RACH resource association relationship mapping ratios can be configured for different TRPs.

[0182] In addition to the transmission resource, index, etc. Information of SSB to represent TRP, the relevant broadcast message or signal corresponding to SSB can also carry TRP information.

[0183] In some embodiments, the TRP information is indicated or determined by at least one of the following ways:

[0184] 1) A first parameter associated with the TRP is configured in the broadcast message, and the broadcast message includes at least one of the following: MIB; SIB1; L1-payload.

[0185] 2) DMRS in SSB, such as DMRS sequence, time domain or frequency domain offset of DMRS.

[0186] 3) Synchronization signal.

[0187] For example, sequence generation of PSS and / or SSS, second parameter associated with the TRP in the generation of PSS and / or SSS sequence; length of PSS and / or SSS sequence; number of PSS and / or SSS sequence; relationship between PSS and SSS, such as time domain interval between the two (the time domain interval between PSS and SSS can be designed according to the coverage of different TRPs).

[0188] At this time, the network side also needs to send multiple sets of SSBs, and different SSBs carry different TRP information (for example, different TRP information in MIB, or different DMRS sequences, or different synchronization signals). Through the above method, the terminal can obtain the TRP information corresponding to the SSB after detecting the SSB. On the other hand, it is also to let the terminal distinguish which SSBs in multiple SSBs correspond to the same TRP, which is beneficial to the terminal to perform subsequent uplink transmission and downlink reception of random access.

[0189] In addition to indicating or determining the association between SSB and TRP, the network side also needs to inform the terminal of the transmission mode of the subsequent random access uplink or downlink message, that is, whether to use STRP or MTRP mode, or the corresponding number of TRPs. The following embodiments are for the case of determining the transmission mode before initiating random access.

[0190] In some embodiments, the transmission mode or TRP information corresponding to the random access (including uplink and downlink messages) is determined by at least one of the following one to five:

[0191] I. Explicitly indicate at least one of the following in the broadcast message: transmission mode, including STRP, MTRP (specific transmission modes include TDM, FDM, SFN, etc.); the number of TRPs; TRP identification.

[0192] II. Implicitly determine the transmission mode or TRP information through the SSB, including at least one of the following:

[0193] 1) The sequence of the demodulation reference signal DMRS in the SSB, for example, the sequence generation of the DMRS implies the transmission mode (or the number of TRPs or the TRP identification).

[0194] 2) The time domain offset of the DMRS in the SSB.

[0195] 3) The frequency domain offset of the DMRS in the SSB.

[0196] 4) The sequence generation method of the synchronization sequence in the SSB, for example, the sequence generation of the PSS and / or SSS implies the transmission mode (or the number of TRPs or the TRP identification).

[0197] 5) The length of the synchronization sequence in the SSB.

[0198] 6) The number of synchronization sequences in the SSB.

[0199] 7) The transmission resource relationship between the synchronization sequences in the SSB, for example, the time domain interval between PSS and SSS.

[0200] 8) The time-frequency resource relationship between multiple SSBs, for example, the time domain or frequency domain interval between SSBs, such as meeting a certain condition or pattern (pattern) corresponds to a certain transmission mode.

[0201] 9) The SSBs existing in a certain time domain or frequency domain window, for example, if two SSBs (corresponding to different TRPs respectively) appear in a predetermined frequency domain window, it is an MTRP transmission mode.

[0202] Three, determine the transmission mode or TRP information through the configured PRACH resource.

[0203] This embodiment determines the transmission mode or TRP information through at least one of the following:

[0204] 1) The length of the preamble corresponding to the PRACH resource, for example, different preamble lengths correspond to different transmission modes.

[0205] 2) The format of the preamble corresponding to the PRACH resource.

[0206] 3) The number of groups of preambles corresponding to the PRACH resource, for example, different numbers of groups correspond to different numbers of TRPs.

[0207] 4) The relationship between ROs or RO groups corresponding to the PRACH resource, such as the time-frequency and / or frequency domain resource relationship between ROs.

[0208] 5) The number of RO groups corresponding to the PRACH resource, for example, different numbers of RO groups correspond to different numbers of TRPs.

[0209] Four, indicate the transmission mode or TRP information through the PRACH resource configuration signaling.

[0210] 1) The indication of the PRACH resource configuration signaling, wherein the transmission mode or TRP information is explicitly indicated in the PRACH resource configuration signaling.

[0211] 2) Define the corresponding TRP or TRP group in the PRACH configuration table, such as introducing a column in the PRACH configuration table to specify the TRP under different configurations; for example, in the PRACH configuration table, define the associated TRP table for one or more PRACH occasions within a PRACH period or a PRACH slot.

[0212] Five, determine the transmission mode or TRP information through the first frequency domain resource.

[0213] The first frequency domain resource includes one or more of the following factors: 1) one or more frequency bands; 2) one or more BWPs; 3) specific frequency resources Frequency, such as specific PRBs; 4) one or more subbands; 5) carriers or carrier groups; 6) one or more serving cells.

[0214] At this time, if the transmission mode indicated by the network side is STRP, or the number of TRPs is 1, the terminal can detect the optimal SSB; if the network side indicates that the default transmission is MTRP (for example, the number of TRPs is 2), after the terminal detects the SSB of one of the TRPs, the terminal needs to detect the SSB of the other TRP in some cases, so as to select the optimal SSB pair; of course, in some cases, the terminal can also detect only one SSB (at this time, the two TRPs can correspond to the same SSB, for example, SFN transmission mode). As for the correspondence between the SSB and the TRP, the method is given in the foregoing embodiment.

[0215] It should be noted that the transmission mode of the uplink message and the downlink message of the random access, or the corresponding number of TRPs, can be different. For example, the downlink message corresponds to multiple TRPs (TRP1 and TRP2), but the uplink message corresponds to one TRP (one of TRP1 and TRP2, or another TRP3).

[0216] In addition, the corresponding PRACH resource also needs to be further designed to correspond to the transmission mode or TRP of PRACH.

[0217] In some embodiments, the PRACH resource associated with the TRP is as follows:

[0218] I. For the uplink MTRP case, at least one of the following is included: 1) each TRP corresponds to an RO group, and the RO group can be the same in the frequency domain or the same in the time domain; there is an association relationship between the RO groups. 2) Each TRP corresponds to a preamble group, and there is an association relationship between the preamble groups.

[0219] II. For the uplink STRP case, different TRPs can correspond to the same PRACH resource.

[0220] For example, different SSB groups correspond to the same PRACH resource.

[0221] In this way, for the uplink MTRP case, PRACH reception can be performed by multiple TRPs. Different ROs or preambles can effectively avoid interference between TRPs and help improve the performance of PRACH reception. The correspondence between the TRP and the RO can be configured in the broadcast message, such as MIB, SIB1.

[0222] For the uplink STRP case: different TRPs can also correspond to the same PRACH resource. Since the coverage ranges of multiple TRPs are different, they do not affect each other, and this method can effectively improve the utilization rate of PRACH resources (such as preambles and ROs), thereby improving the capacity of random access.

[0223] After the transmission mode switching, the network side also needs to adjust the corresponding receiving strategy to match the uplink transmission after the switching to ensure the reception of Msg1 or MsgA or RACH-less PUSCH. For example, the terminal performs the reception of Msg1 or MsgA on two ROs or RO groups corresponding to two TRPs respectively, or performs the reception of Msg1 or MsgA based on the sequence assumption of two preambles or preamble groups corresponding to two TRPs respectively.

[0224] Embodiment Two

[0225] This embodiment mainly introduces the switching of the transmission mode or TRP (which can be understood as dynamic determination) in the RACH process.

[0226] The second case is the switching of the TRP or the transmission mode in the RACH process. Or it can be understood that some steps in the RACH process are performed on different TRPs or different transmission modes, so as to help select the optimal TRP for transmission for each step of the RACH process, improve the performance, capacity and efficiency of random access, reduce power consumption and interference between users. Therefore, how to indicate or determine the switching of the TRP or the transmission mode is one of the key problems. The messages in the RACH stage can be described respectively.

[0227] First, for the third uplink signal (Msg1 or MsgA or RACH-less PUSCH), the method in embodiment one can be used to determine the receiving TRP or the uplink transmission mode. However, when the reception of Msg1, MsgA or RACH-less PUSCH is unsuccessful, the retransmission of Msg1, MsgA or RACH-less PUSCH can use a different transmission mode. Here, Msg1, MsgA or RACH-less PUSCH refers to the first uplink transmission of the random access process.

[0228] In some embodiments: the switching of the transmission mode or TRP of Msg1, MsgA or RACH-less PUSCH is performed when a first condition is reached, and the first condition includes at least one of the following:

[0229] 1) The number of retransmissions of the random access related third uplink signal (Msg1, MsgA or RACH-less PUSCH) reaches a first number. For example, the number of retransmissions of the third uplink signal on one or a group of SSBs or one or a group of TRP-associated PRACH and / or PUSCH resources reaches a first number.

[0230] 2) The transmission power of the third uplink signal related to random access reaches the first power. For example, the third uplink signal transmits on one or a group of SSBs or one or a group of TRP-associated PRACH and / or PUSCH resources with a transmission power reaching the first power.

[0231] 3) The detection time of the response message of the third uplink signal related to random access reaches the first time.

[0232] At this time, the switching of the TRP or the switching of the transmission mode can be performed. For example, the TRP corresponding to the SSB initially selected by the terminal is TRP1, however, after N times of retransmission of Msg1 or MsgA or RACH-less PUSCH, it is still unsuccessful. At this time, the terminal can select another SSB corresponding to TRP2 with better RSRP according to the results of the detection of other SSBs previously, and perform Msg1 or MsgA or RACH-less PUSCH transmission based on MTRP.

[0233] For Msg1 or MsgA or RACH-less PUSCH, the corresponding PRACH resource also needs to be further designed to support its corresponding transmission mode or TRP.

[0234] In some embodiments, the PRACH resource associated with the TRP is as follows:

[0235] I. For the uplink MTRP case, at least one of the following is included: 1) each TRP corresponds to a RO group, and the RO groups can be the same in frequency domain or the same in time domain; there is an association relationship between the RO groups. 2) Each TRP corresponds to a preamble group, and there is an association relationship between the preamble groups.

[0236] II. For the uplink STRP case, different TRPs can correspond to the same PRACH resource.

[0237] For example, different SSB groupings correspond to the same PRACH resource.

[0238] In this way, for the uplink MTRP case, PRACH reception can be performed by multiple TRPs. Using different ROs or preambles can effectively avoid interference between TRPs and help improve the performance of PRACH reception. The correspondence between the TRP and the RO can be configured in the broadcast message, such as MIB, SIB1.

[0239] For the case of uplink STRP: Different TRPs can also correspond to the same PRACH resource. Since the coverage of multiple TRPs is different, they do not affect each other, and this method can effectively improve the utilization of PRACH resource (Preamble, RO) and thus improve the capacity of random access.

[0240] After the transmission mode is switched, the network side also needs to adjust the corresponding receiving strategy to match the uplink transmission after the switch to ensure the reception of Msg1, MsgA or RACH-less PUSCH. For example, the terminal performs Msg1 or MsgA reception on two ROs or RO groups corresponding to two TRPs, or performs Msg1 or MsgA reception based on the sequence assumption of two preambles or preamble groups corresponding to two TRPs.

[0241] For the Msg2, MsgB or feedback message to RACH-less PUSCH, the corresponding transmission mode or TRP can be determined in the following way.

[0242] In some embodiments, the transmission mode or TRP corresponding to the Msg2, MsgB or RACH-less PUSCH feedback message is determined in at least one of the following ways:

[0243] 1) The resource corresponding to the third uplink signal related to random access, such as PRACH resource or RACH-less PUSCH resource.

[0244] For example, the preamble or RO or PUSCH resource corresponding to the Msg1 or MsgA sent by the terminal, or the RACH-less PUSCH resource sent by the terminal.

[0245] For example, the terminal sends a preamble on two ROs, which implicitly informs the network side that the subsequent Msg2 or MsgB transmission will be performed in the MTRP mode.

[0246] Among them, the second downlink signal can be Msg2; MsgB; response message of RACH-less PUSCH, and the second downlink signal can also be the same as the first downlink signal.

[0247] 2) DCI scheduling the second downlink signal related to random access. For example, the physical layer control information DCI scheduling Msg2 or MsgB or RACH-less PUSCH feedback message.

[0248] 3) RRC signaling, such as handover command signaling; beam failure recovery (BFR) signaling, etc.

[0249] 4) first reference signal, such as WUS.

[0250] The embodiment can also determine or switch the transmission scheme corresponding to the second downlink signal related to random access through system messages (such as SIB1).

[0251] The DCI or RRC signaling in the embodiment can be used to indicate at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The above indicated information is associated with the TRP.

[0252] For example, assuming that the preamble is transmitted on TRP1, when sending RAR, if the network side wants to adjust the TRP transmitting RAR to TRP2, the terminal can be instructed to switch the TRP through the above DCI or RRC signaling, that is, to prepare the receiving process corresponding to TRP2, such as receiver algorithm, QCL assumption, etc.

[0253] For Msg3, the corresponding transmission mode or TRP information can be determined in the following ways.

[0254] In some embodiments, the transmission mode or TRP information corresponding to Msg3 is determined in one or more of the following ways:

[0255] 1) default agreement, which is to agree that the transmission scheme corresponding to the fourth uplink signal related to random access is the same as the transmission scheme corresponding to the third uplink signal related to random access.

[0256] 2) the number of retransmissions of the fourth uplink signal related to random access.

[0257] 3) indication in the second downlink signal related to random access.

[0258] The fourth uplink signal in the embodiment can be Msg3, and the fourth uplink signal can also be the same as the first uplink signal. The third uplink signal includes, for example, Msg1; MsgA; RACH-less PUSCH.

[0259] The second downlink signal may, for example, be RAR, which indicates at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The above indicated information is associated with the TRP.

[0260] A simpler method is to default the transmission mode or TRP information corresponding to Msg1 and Msg3 to be the same, which is beneficial to simplify the complexity of the terminal. However, if the optimal TRP needs to be switched when sending Msg3, for example, the optimal TRP changes from TRP1 to TRP2 after the terminal moves, the network side can instruct the terminal to switch the transmission TRP when sending Msg3; or Msg1 is received on a macro TRP, and when receiving Msg3, the network side wants to switch the TRP to a small TRP to reduce the burden of the macro TRP, at which time the TRP can also be switched. Even multiple small TRPs can be used to receive Msg3 in the form of MTRP, thereby improving the reception performance of Msg3.

[0261] Considering the complexity of the base station or the terminal, it is possible that a certain time is needed for transmission preparation before the terminal switches the transmission mode or TRP of Msg3. At this time, the scheduling of Msg3 can be subject to additional constraints.

[0262] In some embodiments, the time interval between the RAR or fallback RAR and Msg3 is determined, including one of the following:

[0263] 1) A predefined time interval, such as introducing an additional time interval K.

[0264] This can increase the time interval between Msg2 or MsgB and Msg3, for example, as shown in the following table, an additional time offset in the unit of PUSCH slot is defined for the determination of the uplink transmission time of Msg3 after switching the TRP. The size of the time offset here can be related to at least the subcarrier spacing of the PUSCH or the slot of the Msg3 PUSCH.

[0265] 2) Introduce a default rule or requirement to constrain the minimum time interval.

[0266] For example, it is agreed that the time interval between the scheduling DCI or the scheduling RAR or fallback RAR and the Msg3 PUSCH for the transmission of Msg3 after switching the TRP or QCL or TCI is not less than a certain or certain group of network defined values.

[0267] This can enable the base station and the terminal to have more sufficient time to cope with the adjustment of the transmission mode or TRP.

[0268] For Msg4, the corresponding transmission mode or TRP information can be determined in the following way.

[0269] In some embodiments, the corresponding transmission mode or TRP of the Msg4 transmission or repeated transmission or retransmission is determined by at least one of the following ways:

[0270] 1) The same as the determination method of the transmission mode or TRP of Msg2.

[0271] 2) It is agreed that the transmission mode or TRP of Msg2 is consistent with that of Msg4.

[0272] 3) In Msg3, request or indicate one or a group of transmission modes of the corresponding Msg4 transmission or repeated transmission or retransmission, and the network side can choose to switch or not to switch.

[0273] 4) Indicated in the DCI scheduling Msg4. The DCI can indicate at least one of the following: TRP index, SSB information, QCL or TCI, preamble information, RO information, PUSCH resource information, MTRP transmission mode (including SFN, FDM, TDM, SDM). The above indicated information is associated with the TRP.

[0274] The overall idea is similar to Msg2, and the main feature is that the terminal can perform transmission mode or TRP switching in Msg3 according to the reception quality of Msg4. For example, the terminal still cannot successfully receive Msg4 under the preset condition, and can perform switching request through Msg3.

[0275] Embodiment three

[0276] This embodiment mainly introduces how to determine the QCL information.

[0277] In the current NR system, it can be understood that the random access is completed on one TRP. Therefore, after the terminal selects an optimal SSB in the initial access stage, the uplink and downlink QCL assumption (including spatial relationship) in the subsequent random process is based on the SSB, and the QCL assumption will not be switched in some steps.

[0278] Then as described in embodiment one and embodiment two, if for a cell-free system, the random process can be performed on multiple TRPs (i.e. MTRP), or some steps of the random process are performed on different TRPs (i.e. TRP switching), then the uplink and downlink QCL assumption also needs to be enhanced accordingly.

[0279] First, for the case that the transmission mode or TRP information is determined before the RACH is initiated. At this time, it can be understood that the transmission mode or TRP adjustment is not performed in the subsequent RACH process. Therefore, the QCL assumption does not need to be changed. Only QCL enhancement needs to be performed for the MTRP scenario. The terminal selects the SSB associated with the TRP corresponding to the MTRP as the QCL assumption for sending the random access related uplink or downlink message.

[0280] In some embodiments, the terminal detects one or more groups of SSBs (such as each group corresponding to the number of TRPs of MTRP).

[0281] Assuming that the terminal knows that the subsequent random access process is MTRP transmission, for example, based on 3 TRPs, the terminal needs to measure the SSBs of the corresponding TRPs, and select the optimal 3 SSBs, that is, the SSB combination, as the uplink and downlink QCL assumption for subsequent transmission.

[0282] For the case of transmission mode or TRP switching in the RACH process, the switching of the transmission mode or TRP will cause the change of the QCL assumption, including the transmission of the uplink message and the downlink message. Therefore, how to determine the QCL assumption corresponding to the uplink and downlink transmission is very important.

[0283] In some embodiments, the QCL assumption of signal transmission can be determined in one or more of the following ways (such as mainly for the dynamic QCL assumption scenario):

[0284] I. The network side indicates the second signaling indication.

[0285] The indication of the second signaling includes one or more of the following ways:

[0286] 1) Indicated in the DCI scheduling RAR or fallback RAR.

[0287] Downlink: The DCI used to indicate RAR or schedule Msg4 or the QCL of Msg4.

[0288] Uplink: The QCL (including spatial relation) used to indicate Msg3.

[0289] 2) Indicated in RAR or fallback RAR.

[0290] 3) Indicated in Msg4 DCI.

[0291] 4) Indicated in Msg4.

[0292] 5) System message.

[0293] 6) MAC-CE signaling.

[0294] For example, for a terminal entering connected state, the network can use MAC-CE to indicate the QCL assumption corresponding to at least partial PDCCH reception on at least partial common search space.

[0295] For example, a bitmap can be used on MAC-CE to indicate whether the QCL assumption of a group of PDCCH monitoring occasions (MO) is a certain or another SSB.

[0296] The second signaling carries the following first information associated with (or used to represent) QCL assumption, and the first information includes at least one of the following: TRP index; SSB information (e.g., index, group index, transmission resource index); preamble information (e.g., index, group index); PUSCH information; RO information (e.g., index, group index).

[0297] The message in which the second signaling is located can be scrambled by a first RNTI (e.g., QCL-RNTI) or the CRC of the message in which the second signaling is located is scrambled by the first RNTI.

[0298] For example, the message in which the second signaling is located is a DCI format.

[0299] For example, the DCI here can be a common DCI (common DCI) used to indicate the QCL assumption of the random access search space (RA search space).

[0300] II. The terminal reports or recommends the DCI scheduling Msg4 or the QCL assumption of Msg4 through Msg3.

[0301] The terminal can default to agree that the network side will subsequently use the reported or recommended QCL assumption to transmit the DCI scheduling Msg4 or transmit Msg4. Similarly, the terminal will receive the DCI scheduling Msg4 or receive Msg4 using the reported or recommended QCL assumption.

[0302] Or the terminal can default to agree that the network side will subsequently use the reported or recommended QCL assumption to transmit the DCI scheduling Msg4, while the QCL assumption of Msg4 transmission is still indicated by the DCI scheduling Msg4. Similarly, the terminal can receive the DCI scheduling Msg4 using the reported or recommended QCL assumption, while the QCL assumption of Msg4 reception is still indicated by the DCI scheduling Msg4.

[0303] Three, the terminal reports or recommends the DCI or QCL assumption of MsgB scheduling by MsgA PUSCH.

[0304] The terminal can default to agree with the network side to subsequently transmit the DCI of scheduling MsgB or the transmission of MsgB with the reported or recommended QCL assumption. Similarly, the terminal receives the DCI of scheduling MsgB or the reception of MsgB with the reported or recommended QCL assumption.

[0305] Or the terminal can default to agree with the network side to subsequently transmit the DCI of scheduling MsgB with the reported or recommended QCL assumption, while the QCL assumption of MsgB transmission is still indicated by the DCI of scheduling MsgB. Similarly, the terminal can receive the DCI of scheduling MsgB with the reported or recommended QCL assumption, while the QCL assumption of MsgB reception is still indicated by the DCI of scheduling MsgB.

[0306] Four, the terminal requests or indicates or recommends the QCL assumption of a specific subsequent signal transmission through transmission on a specific PRACH or WUS resource.

[0307] Through the above two methods, the indication of QCL or TCI can be realized, so that the terminal can correctly send uplink messages and receive downlink messages. It should be noted that when the transmission mode is MTRP, multiple first information is indicated in the second signaling.

[0308] In addition, in some cases, the downlink message can also be received in the form of TDM, including TDM-based MTRP transmission. Especially for PDCCH, PDCCH reception can be performed on different PDCCH monitoring occasions MO (corresponding to different periods of search space). At this time, when the terminal knows the correspondence between the TRP and the SSB in advance, the terminal can receive the PDCCH with the SSB corresponding to the TRP corresponding to the MO corresponding to the PDCCH as the QCL assumption, and the PDCCH includes the DCI scheduling RAR and the DCI scheduling Msg4. However, the transmission order of each TRP needs to be agreed, so that the terminal can receive correctly with the correct QCL assumption on the corresponding MO.

[0309] In some embodiments, there is a mapping relationship between one or a group of TRPs or SSBs and PDCCH resources, including one of the following:

[0310] 1) One-to-one correspondence between SSB or TRP group and specific PDCCH resource (such as one or more MOs or MOs within one or more windows).

[0311] 2) SSB or TRP is one-to-one corresponding to the PDCCH specific resource (such as one or more MOs or MOs within one or more windows).

[0312] The mapping relationship can be agreed by default in the protocol (for example, it is agreed by default that there are N MOs within a certain window, and each corresponds to a corresponding TRP or SSB); or indicated through a broadcast message. The terminal can learn the corresponding TRP of the PDCCH on each MO before performing the PDCCH reception, so as to enable the terminal to correctly adjust the QCL assumption of the reception. For example, it is determined that the PDCCH is transmitted through TRP1, TRP2, and TRP3, and the three TRPs correspond to three SSB groups respectively. The terminal selects the optimal SSB in the three SSBs in the previous SSB detection, and then the terminal takes the three optimal SSBs as the QCL assumption on the three MOs of the PDCCH. Optionally, at this time, it can be agreed by default that other signals in the random access process, such as PDSCH, have the same QCL assumption as the PDCCH.

[0313] When the isolation degree between multiple TRPs is relatively large, the same PDCCH resource can be shared, that is, the same PDCCH resource can be associated with different SSBs or SSB groups. Therefore, there are the following embodiments.

[0314] In some embodiments, the same PDCCH resource can be associated with different SSBs or different SSB groups.

[0315] In order to reduce the complexity of the terminal, the PDCCH resource can also be enabled. For example, when only part of the TRPs are turned on, the PDCCH detection on the PDCCH resource corresponding to the turned-on TRP can be enabled, thereby reducing the detection overhead of the PDCCH.

[0316] In some embodiments, the PDCCH resource is enabled through third signaling.

[0317] For example, the third signaling can enable the PDCCH resource in the form of bitmap, at this time, the enabling of the PDCCH resource can also be understood as the enabling of the TRP.

[0318] At this time, the terminal only performs PDCCH reception on the enabled MO.

[0319] For the PDCCH specific resource in the foregoing embodiments, the PDCCH specific resource can be one or more MOs or MOs within one or more windows, PDCCH resources corresponding to specific CCEs, REGs, search spaces (such as RA search spaces), specific aggregation levels, and the like.

[0320] Embodiment four

[0321] This embodiment mainly introduces power control.

[0322] Similar to the QCL assumption, when the transmission mode or TRP switches, due to the different reference signals (such as SSB) corresponding to different TRPs for path loss estimation, the path loss reference signal used for power control of the related uplink signal also needs to be switched. Among them, the related uplink signal includes at least one of PRACH, Msg3, MsgA PUSCH, Msg4 PUCCH, SRS, CG PUSCH, WUS signal, TRS, DMRS, etc. That is, the power control reference signal of the related uplink signal is associated with the TRP or SSB selected by it, and the specific association relationship is not described here. Please refer to the transmission mode or TRP determination and switching part in embodiments one, two and three.

[0323] The above describes in detail the random access method according to the embodiments of the present application in combination with Figure 2. The random access method according to another embodiment of the present application will be described in detail below in combination with Figure 3. It can be understood that the interaction between the network side device described from the network side device and the terminal is the same as or corresponds to the description of the terminal side in the method shown in Figure 2. In order to avoid repetition, the relevant description is appropriately omitted.

[0324] Figure 4 is a flowchart of the random access method according to the embodiments of the present application, which can be applied to a network side device. As shown in Figure 4, the method 400 includes the following steps.

[0325] S402: The network side device performs a second operation, which includes at least one of the following: sending multiple sets of first synchronization signals; determining or indicating the transmission scheme corresponding to the random access related signal; determining or indicating the time interval between the random access related first downlink signal and the random access related first uplink signal; determining or indicating the QCL information corresponding to the random access related signal; determining or indicating the related information of the random access related PDCCH resource; determining or indicating the path loss reference signal corresponding to the power control of the random access related second uplink signal.

[0326] In this embodiment, the second operation performed by the network side device can refer to the description of the first operation of the terminal side, which will not be described in detail here.

[0327] The random access method provided in the embodiments of the present application is beneficial to improving the performance of random access in a cell-free or other large cell multi-TRP system.

[0328] The random access method provided in the embodiments of the present application is executed by a random access device. In the embodiments of the present application, the random access method is taken as an example to illustrate the random access device provided in the embodiments of the present application.

[0329] The random access device provided in the embodiments of the present application can be a communication device or a component in a communication device, for example, a chip. The communication device can be a terminal, a network side device or a server, etc. For example, the terminal can include, but is not limited to, the types of the terminal 11 listed above, the network side device can include, but is not limited to, the types of the network side device 12 listed above, and the embodiments of the present application are not limited specifically.

[0330] The random access device includes a receiving module, a sending module and a processing module. The receiving module, the sending module and the processing module can be implemented by software or by hardware. When implemented by hardware, the processing module can be implemented by a processor, for example, a general processor, a special processor, etc., such as a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), an artificial intelligent (AI) processor, a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a network processor (NP), a field programmable gate array (FPGA) or other programmable logic devices, a gate circuit, a transistor, a discrete hardware component, etc. The receiving module and the sending module can be implemented by a communication interface, which can include one or more of a transceiver, a pin, a circuit, a bus, a radio frequency unit, etc.

[0331] Specifically, referring to FIG. 5, when the random access apparatus is a terminal or a component in the terminal, the random access apparatus 500 includes a processing module 502 configured to perform a first operation, the first operation including at least one of the following: measuring at least one set of first synchronization signals in a plurality of sets of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to the random access related signal; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0332] The random access apparatus provided by the embodiments of the present application is beneficial to improving the performance of random access in a cell-free or other large cell multi-TRP system, by measuring at least one set of first synchronization signals in a plurality of sets of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to the random access related signal; determining related information of a random access related PDCCH resource; and determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0333] In one embodiment, the processing module 502 is configured to determine the transmission scheme by at least one of the following: a broadcast message; a first synchronization signal; a PRACH resource; PRACH resource configuration signaling; and a first frequency domain resource.

[0334] In one embodiment, the processing module 502 is configured to determine or switch a transmission scheme corresponding to a random access related third uplink signal in a case where a first condition is met; wherein the first condition includes that the random access related third uplink signal meets at least one of the following: a retransmission number of the random access related third uplink signal reaches a first number; a transmission power of the random access related third uplink signal reaches a first power; and a detection time of a response message of the random access related third uplink signal reaches a first time.

[0335] In one embodiment, the processing module 502 is configured to determine or switch a transmission scheme corresponding to a random access related second downlink signal by at least one of the following: a resource corresponding to a random access related third uplink signal; DCI scheduling the random access related second downlink signal; RRC signaling; and a first reference signal.

[0336] In an embodiment, the processing module 502 is configured to determine or switch the transmission scheme corresponding to the random access related fourth uplink signal by at least one of the following: a default agreement that the transmission scheme corresponding to the random access related fourth uplink signal is the same as the transmission scheme corresponding to the random access related third uplink signal; the number of retransmissions of the random access related fourth uplink signal; an indication in the random access related second downlink signal.

[0337] In an embodiment, the processing module 502 is configured to determine or switch the transmission scheme corresponding to the random access related third downlink signal by at least one of the following: the resource corresponding to the random access related third uplink signal; the DCI scheduling the random access related second downlink signal; RRC signaling; the first reference signal; a default agreement that the transmission scheme corresponding to the random access related third downlink signal is the same as the transmission scheme corresponding to the random access related second downlink signal; a request or indication in the random access related fourth uplink signal; the DCI scheduling the random access related third downlink signal.

[0338] In an embodiment, the processing module 502 is configured to determine the time interval based on at least one of the following: a predefined time interval; a predefined rule.

[0339] In an embodiment, at least one of the QCL corresponding to the random access related signals and the power control reference signal corresponding to the random access related second uplink signal is determined by at least one of the following: a report or recommendation of Msg3; a report or recommendation of PUSCH of MsgA; a PRACH resource; a WUS resource; an indication of a second signaling; wherein the second signaling comprises at least one of the following: a RAR or fallback RAR; a DCI scheduling the RAR or fallback RAR; a DCI scheduling Msg4; Msg4; a system message; a first MAC-CE signaling.

[0340] In an embodiment, the related information of the random access related PDCCH resource comprises at least one of the following: a mapping relationship between the random access related PDCCH resource and at least one set of first synchronization signals; an enabling condition of the random access related PDCCH resource.

[0341] Referring to FIG. 6, when the random access apparatus is a network-side device or a component in the network-side device, the random access apparatus 600 includes a processing module 602 configured to perform a second operation, the second operation including at least one of: sending multiple sets of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random process related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of a random access related PDCCH resource; and determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0342] The random access apparatus provided by the embodiments of the present application is beneficial to improving the performance of random access in a cell-free or other large cell multi-TRP system, by sending multiple sets of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random process related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of a random access related PDCCH resource; and determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

[0343] The random access apparatus provided by the embodiments of the present application can implement each process achieved by the method embodiments of FIGS. 3 to 4, and achieve the same technical effects. To avoid repetition, details are not described herein.

[0344] As shown in FIG. 7, the embodiments of the present application further provide a communication device 700, including a processor 701 and a memory 702, the memory 702 has a program or instruction stored thereon, which can be run on the processor 701. For example, when the communication device 700 is a terminal, the program or instruction is executed by the processor 701 to implement each step of the above random access method embodiments, and can achieve the same technical effects. When the communication device 700 is a network-side device, the program or instruction is executed by the processor 701 to implement each step of the above random access method embodiments, and can achieve the same technical effects. To avoid repetition, details are not described herein.

[0345] The embodiments of the present application further provide a terminal, including a processor and a communication interface, the communication interface and the processor are coupled, and the processor is configured to run a program or instruction to implement the steps in the method embodiments as shown in FIG. 3. The terminal embodiment corresponds to the above terminal-side method embodiments, each implementation process and implementation manner of the above method embodiments can be applied to the terminal embodiment, and the same technical effects can be achieved. The terminal can be the random access apparatus shown in FIG. 5. Specifically, FIG. 8 is a hardware structure schematic diagram of a terminal for implementing the embodiments of the present application.

[0346] The terminal 800 includes, but is not limited to, at least part of components such as a radio frequency unit 801, a network module 802, an audio output unit 803, an input unit 804, a sensor 805, a display unit 806, a user input unit 807, an interface unit 808, a memory 809, and a processor 810.

[0347] Those skilled in the art can understand that the terminal 800 can further include a power supply (such as a battery) for supplying power to each component, and the power supply can be logically connected to the processor 810 through a power management system, so as to realize functions such as management of charging, discharging, and power consumption management through the power management system. The terminal structure shown in FIG. 8 does not constitute a limitation on the terminal, and the terminal can include more or fewer components than those shown, or combine certain components, or different component arrangements, which are not described here.

[0348] It should be understood that in the embodiments of the present application, the input unit 804 can include a graphics processor 8041 and a microphone 8042, and the graphics processor 8041 processes image data of a still picture or a video obtained by an image capture device (such as a camera) in a video capture mode or an image capture mode. The display unit 806 can include a display panel 8061, which can be configured in the form of a liquid crystal display, an organic light-emitting diode, etc. The user input unit 807 includes at least one of a touch panel 8071 and other input devices 8072. The touch panel 8071 is also called a touch screen. The touch panel 8071 can include two parts of a touch detection device and a touch controller. The other input devices 8072 can include, but are not limited to, a physical keyboard, function keys (such as volume control keys, on-off keys, etc.), trackballs, mice, joysticks, which are not described here.

[0349] In the embodiments of the present application, the radio frequency unit 801 can transmit the downlink data received from the network side device to the processor 810 for processing. In addition, the radio frequency unit 801 can send uplink data to the network side device. Generally, the radio frequency unit 801 includes, but is not limited to, an antenna, an amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, etc.

[0350] The memory 809 can be used to store software programs or instructions and various data. The memory 809 can mainly include a first storage area storing programs or instructions and a second storage area storing data, wherein the first storage area can store an operating system, application programs or instructions required by at least one function (such as a sound playing function, an image playing function, etc.), and the like. In addition, the memory 809 can include a volatile memory or a non-volatile memory. The non-volatile memory can be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically EPROM (EEPROM), or a flash memory. The volatile memory can be a Random Access Memory (RAM), a Static RAM (SRAM), a Dynamic RAM (DRAM), a Synchronous DRAM (SDRAM), a Double Data Rate SDRAM (DDR SDRAM), an Enhanced SDRAM (ESDRAM), a Synch link DRAM (SLDRAM), and a Direct Rambus RAM (DRRAM). The memory 809 in the embodiments of the present application includes but is not limited to these and any other suitable types of memory.

[0351] The processor 810 can include one or more processing units; optionally, the processor 810 integrates an application processor and a modem processor, wherein the application processor mainly processes operations related to an operating system, a user interface, and an application program, and the modem processor mainly processes wireless communication signals, such as a baseband processor. It can be understood that the above-mentioned modem processor can also not be integrated into the processor 810.

[0352] The processor 810 is configured to perform a first operation, and the first operation includes at least one of the following: measuring at least one set of first synchronization signals in a plurality of sets of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to a random access related signal; determining related information of a random access related PDCCH resource; and determining a power control corresponding to a loss reference signal of a random access related second uplink signal.

[0353] The terminal provided by the embodiment of the present application measures at least one set of first synchronization signals in multiple sets of first synchronization signals, determines a transmission scheme corresponding to a random access related signal, determines a time interval between a random access related first downlink signal and a random access related first uplink signal, determines QCL information corresponding to the random access related signal, determines related information of a random access related PDCCH resource, and determines a path loss reference signal corresponding to power control of a random access related second uplink signal, which is beneficial to improving the performance of random access in a cell-free or other large cell multi-TRP system.

[0354] It can be understood that the implementation processes of the implementation manners mentioned in the embodiment can refer to the related descriptions of the random access method embodiments and achieve the same or corresponding technical effects. To avoid repetition, they will not be described here again.

[0355] The embodiment of the present application also provides a network side device, which comprises a processor and a communication interface, the communication interface and the processor are coupled, and the processor is used to run programs or instructions to realize the steps of the method embodiment shown in FIG. 4. The network side device embodiment corresponds to the network side device method embodiment described above, and each implementation process and implementation manner of the method embodiment described above can be applied to the network side device embodiment and can achieve the same technical effects.

[0356] Specifically, the embodiment of the present application also provides a network side device, which can be the random access apparatus shown in FIG. 6. As shown in FIG. 9, the network side device 900 comprises an antenna 91, a radio frequency device 92, a baseband device 93, a processor 94 and a memory 95. The antenna 91 is connected with the radio frequency device 92. In the uplink direction, the radio frequency device 92 receives information through the antenna 91 and sends the received information to the baseband device 93 for processing. In the downlink direction, the baseband device 93 processes the information to be sent and sends it to the radio frequency device 92, and the radio frequency device 92 processes the received information and sends it out through the antenna 91.

[0357] The method performed by the network side device in the above embodiment can be implemented in the baseband device 93, which comprises a baseband processor.

[0358] The baseband device 93 may, for example, comprise at least one baseband board, and a plurality of chips are arranged on the baseband board, as shown in FIG. 9, one of which is a baseband processor, which is connected with the memory 95 through a bus interface to call the programs in the memory 95 and perform the network device operations shown in the above method embodiments.

[0359] The network-side device can further include a network interface 96, for example, a Common Public Radio Interface (CPRI).

[0360] Specifically, the network-side device 900 of the embodiments of the present application further includes instructions or programs stored on the memory 95 and executable on the processor 94, the processor 94 invokes the instructions or programs in the memory 95 to perform the method performed by the modules shown in FIG. 6 and achieve the same technical effects. To avoid repetition, details are not described herein.

[0361] The embodiments of the present application further provide a readable storage medium having programs or instructions stored thereon, the programs or instructions are executed by a processor to implement the processes of the above random access method embodiments and achieve the same technical effects. To avoid repetition, details are not described herein.

[0362] The processor is the processor in the terminal in the above embodiments. The readable storage medium includes a computer readable storage medium, such as a computer readable only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc. In some examples, the readable storage medium can be a non-transitory readable storage medium.

[0363] The embodiments of the present application further provide a chip including a processor and a communication interface, the communication interface and the processor are coupled, the processor is used to run programs or instructions to implement the processes of the above random access method embodiments and achieve the same technical effects. To avoid repetition, details are not described herein.

[0364] It should be understood that the chip mentioned in the embodiments of the present application can also be referred to as a system chip, a system chip, a chip system or a system on chip, etc.

[0365] The embodiments of the present application further provide a computer program / program product stored in a storage medium, the computer program / program product is executed by at least one processor to implement the processes of the above random access method embodiments and achieve the same technical effects. To avoid repetition, details are not described herein.

[0366] The embodiments of the present application further provide a random access system including a terminal and a network-side device, the terminal can be used to execute the steps of the above random access method, and the network-side device can be used to execute the steps of the above random access method.

[0367] It should be noted that, in the present document, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises a", "comprising", or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. Furthermore, it is to be understood that the methods and apparatuses of the present application can be carried out by specific hardware, by software, or by a combination of hardware and software. It is therefore, contemplated to this patent to cover any and all modifications, variations, or equivalents that fall within the scope of the present application. Accordingly, where a concept can have been illustrated in only one of the exemplary embodiments, various aspects of the concept can be modified and / or combined to produce a variety of other embodiments that are not specifically illustrated. Thus, for purposes of describing particular embodiments, reference has been made to orientations. However, it should be understood that the described embodiments can be carried out in other orientations than those explicitly described without departing from the scope of the present application.

[0368] From the above description of the embodiments, it is apparent that the above-mentioned method can be realized by means of a computer software product and a general hardware platform, of course, it can also be realized by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, magnetic disc, optical disc, etc.), and includes a plurality of instructions for making the terminal or network side device execute the method described in each embodiment of the present application.

[0369] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-described specific embodiments, and the above-described specific embodiments are merely illustrative rather than limiting, and a person of ordinary skill in the art can make many forms of embodiments under the inspiration of the present application without departing from the scope of the present application and the scope protected by the claims.

Claims

1. A random access method, comprising: a terminal performing a first operation, the first operation comprising at least one of: measuring at least one of a plurality of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random access related first uplink signal; determining quasi co-location (QCL) information corresponding to a random access related signal; determining related information of a random access related physical downlink control channel (PDCCH) resource; and determining a power control corresponding to a random access related second uplink signal. the plurality of first synchronization signals differ from each other in at least one of: corresponding transmission resources, the transmission resources comprising at least one of: a period, a time window, a frequency domain resource, a transmission occasion; and corresponding first synchronization signal groups. the plurality of first synchronization signals and a physical random access channel (PRACH) resource satisfy at least one of: at least two of the plurality of first synchronization signals correspond to a same PRACH resource; each of the plurality of first synchronization signals corresponds to a random access occasion (RO) group, the RO group corresponding to the PRACH resource; each of the plurality of first synchronization signals corresponds to a preamble group, the preamble group corresponding to the PRACH resource; and a mapping relationship between at least two of the plurality of first synchronization signals and the PRACH resource is configured in a same PRACH resource configuration signaling. the determining a transmission scheme corresponding to a random access related signal comprises: determining the transmission scheme through at least one of: a broadcast message; a first synchronization signal; a PRACH resource; a PRACH resource configuration signaling; and a first frequency domain resource. when the transmission scheme corresponding to the random access related signal is determined through the broadcast message, the broadcast message comprises at least one of: a master information block (MIB); a system information block (SIB); and a layer one payload (L1-payload). when the transmission scheme corresponding to the random access related signal is determined through the first synchronization signal, the transmission scheme is determined through at least one of: a sequence of a demodulation reference signal (DMRS) in the first synchronization signal; a time domain offset of the DMRS in the first synchronization signal; a frequency domain offset of the DMRS in the first synchronization signal; a sequence generation manner of a synchronization sequence in the first synchronization signal; a length of the synchronization sequence in the first synchronization signal; a number of the synchronization sequence in the first synchronization signal; a transmission resource relationship between the synchronization sequence in the first synchronization signal; a time-frequency resource relationship between a plurality of the first synchronization signals; and the first synchronization signal existing in a specific time domain or frequency domain window. when the transmission scheme corresponding to the random access related signal is determined through the PRACH resource, the transmission scheme is determined through at least one of: a length of a preamble corresponding to the PRACH resource. ​ ​ ​ ​ ​ ​ 2. The method of claim 1, wherein, ​ ​ ​ 3. The method of claim 1 or 2, wherein, ​ ​ ​ ​ ​ 4. The method according to any one of claims 1 to 3, wherein, ​ ​ ​ ​ ​ ​ 5. The method of claim 4, wherein, ​ ​ ​ ​ 6. The method of claim 4, wherein, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7. The method of claim 4, wherein, ​ ​ A format of a preamble corresponding to the PRACH resource; A number of groups of preambles corresponding to the PRACH resource; A relationship between ROs or groups of ROs corresponding to the PRACH resource; A number of groups of ROs corresponding to the PRACH resource.

8. The method of claim 4, wherein, When determining the transmission scheme corresponding to the random access related signal through the PRACH resource configuration signaling, the transmission scheme is determined through at least one of the following: An indication of the PRACH resource configuration signaling, wherein the transmission scheme is explicitly indicated in the PRACH resource configuration signaling; A PRACH resource configuration table used for configuring the PRACH resource, wherein the transmission scheme is defined in the PRACH resource configuration table.

9. The method of claim 4, wherein, When determining the transmission scheme corresponding to the random access related signal through the first frequency domain resource, the transmission scheme is determined through at least one of the following: A frequency band; A bandwidth part (BWP); A specific frequency resource; A sub-band; A carrier; A carrier group; A serving cell.

10. The method according to any one of claims 1 to 3, wherein, The determination of the transmission scheme corresponding to the random access related signal comprises, in the case of reaching a first condition, determining or switching the transmission scheme corresponding to a random access related third uplink signal; The first condition comprises that the random access related third uplink signal satisfies at least one of the following: The number of retransmissions of the random access related third uplink signal reaches a first number; The transmission power of the random access related third uplink signal reaches a first power; The detection time of a response message of the random access related third uplink signal reaches a first time.

11. The method according to any one of claims 1 to 10, wherein, The determination of the transmission scheme corresponding to the random access related signal comprises, through at least one of the following, determining or switching the transmission scheme corresponding to a random access related second downlink signal: A resource corresponding to the random access related third uplink signal; Downlink control information (DCI) scheduling the random access related second downlink signal; Radio resource control (RRC) signaling; A first reference signal.

12. The method according to any one of claims 1 to 11, wherein, The determination of the transmission scheme corresponding to the random access related signal comprises, through at least one of the following, determining or switching the transmission scheme corresponding to a random access related fourth uplink signal: A default agreement mode, which is an agreement that the transmission scheme corresponding to the random access related fourth uplink signal is the same as that of a random access related third uplink signal; The number of retransmissions of the random access related fourth uplink signal; An indication in a random access related second downlink signal.

13. The method according to any one of claims 1 to 12, wherein, The determination of the transmission scheme corresponding to the random access related signal comprises, through at least one of the following, determining or switching the transmission scheme corresponding to a random access related third downlink signal: A resource corresponding to the random access related third uplink signal; Downlink control information (DCI) scheduling the random access related second downlink signal; Radio resource control (RRC) signaling; A first reference signal; A default agreement mode, which is an agreement that the transmission scheme corresponding to the random access related third downlink signal is the same as that of a random access related second downlink signal A request or indication in a random access related fourth uplink signal; DCI scheduling the random access related third downlink signal.

14. The method according to any one of claims 1 to 13, wherein, The determining the time interval between the random access related first downlink signal and the random process related first uplink signal comprises determining the time interval based on at least one of the following: a predefined time interval; a predefined rule.

15. The method according to any one of claims 1 to 14, wherein, At least one of the QCL corresponding to the random access related signal and the path loss reference signal corresponding to the power control of the random access related second uplink signal is determined by at least one of the following: reporting or recommending of a random access message three Msg3; reporting or recommending of a physical uplink shared channel PUSCH of a random access message A MsgA; a PRACH resource; a wake-up signal WUS resource; an indication of a second signaling; wherein the second signaling comprises at least one of the following: a random access response RAR or a fallback RAR; a DCI scheduling the RAR or the fallback RAR; a DCI scheduling a random access message four Msg4; the Msg4; a system message; a first medium access control control element MAC-CE signaling.

16. The method of claim 15, wherein, The second signaling and a first radio network temporary identifier RNTI satisfy at least one of the following relationships: a message in which the second signaling is located is scrambled by the first RNTI; a cyclic redundancy check CRC of the message in which the second signaling is located is scrambled by the first RNTI.

17. The method of any one of claims 1 to 16, wherein, The related information of the random access related PDCCH resource comprises at least one of the following: a mapping relationship between the random access related PDCCH resource and at least one set of first synchronization signals; an enabling condition of the random access related PDCCH resource.

18. The method of claim 17, wherein, The random access related PDCCH resource is a PDCCH resource corresponding to at least one of the following: one or more monitoring occasions MOs; MOs within one or more time windows; a group of control elements REGs; a search space; a specific control channel element CCE; a specific aggregation level AL.

19. A random access method, comprising: a network side device performing a second operation, the second operation comprising at least one of the following: sending a plurality of sets of first synchronization signals; determining or indicating a transmission scheme corresponding to a random access related signal; determining or indicating a time interval between a random access related first downlink signal and a random process related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of a random access related PDCCH resource; determining or indicating a path loss reference signal corresponding to power control of a random access related second uplink signal.

20. A random access apparatus, comprising: a processing module configured to perform a first operation, the first operation comprising at least one of the following: measuring at least one set of first synchronization signals from a plurality of sets of first synchronization signals; determining a transmission scheme corresponding to a random access related signal; determining a time interval between a random access related first downlink signal and a random process related first uplink signal; determining QCL information corresponding to the random access related signal; determining related information of a random access related PDCCH resource; determining a path loss reference signal corresponding to power control of a random access related second uplink signal.

21. The apparatus of claim 20, wherein, The processing module is configured to determine the transmission scheme by at least one of the following: a broadcast message; a first synchronization signal; A PRACH resource; PRACH resource configuration signaling; A first frequency domain resource.

22. The apparatus of claim 20, wherein, The processing module is configured to determine or switch a transmission scheme corresponding to a random access related third uplink signal in a case where a first condition is met. The first condition includes that the random access related third uplink signal meets at least one of the following: A number of retransmissions of the random access related third uplink signal reaches a first number; A transmission power of the random access related third uplink signal reaches a first power; A detection time of a response message of the random access related third uplink signal reaches a first time.

23. The apparatus of any one of claims 20 to 22, wherein, The processing module is configured to determine or switch a transmission scheme corresponding to a random access related second downlink signal by at least one of the following: A resource corresponding to the random access related third uplink signal; DCI scheduling the random access related second downlink signal; RRC signaling; A first reference signal.

24. The apparatus of any one of claims 20 to 23, wherein, The processing module is configured to determine or switch a transmission scheme corresponding to a random access related fourth uplink signal by at least one of the following: A default agreement mode, which is an agreement that the transmission scheme corresponding to the random access related fourth uplink signal is the same as the transmission scheme corresponding to the random access related third uplink signal; A number of retransmissions of the random access related fourth uplink signal; An indication in the random access related second downlink signal.

25. The apparatus of any one of claims 20 to 24, wherein, The processing module is configured to determine or switch a transmission scheme corresponding to a random access related third downlink signal by at least one of the following: A resource corresponding to the random access related third uplink signal; DCI scheduling the random access related second downlink signal; RRC signaling; A first reference signal; A default agreement mode, which is an agreement that the transmission scheme corresponding to the random access related third downlink signal is the same as the transmission scheme corresponding to the random access related second downlink signal A request or indication in the random access related fourth uplink signal; DCI scheduling the random access related third downlink signal.

26. The apparatus of any one of claims 20 to 25, wherein, The processing module is configured to determine the time interval based on at least one of the following: A predefined time interval; A predefined rule.

27. The apparatus of any one of claims 20 to 26, wherein, At least one of a QCL corresponding to the random access related signal and a path loss reference signal corresponding to power control of the random access related second uplink signal is determined by at least one of the following: Reporting or recommendation of Msg3; Reporting or recommendation of PUSCH of MsgA; A PRACH resource; A WUS resource; An indication of second signaling, wherein the second signaling includes at least one of the following: RAR or fallback RAR; DCI scheduling RAR or fallback RAR; DCI scheduling Msg4; Msg4; system message; first MAC-CE signaling.

28. The apparatus of any one of claims 20 to 27, wherein, The related information of the random access related PDCCH resource includes at least one of the following: A mapping relationship between the random access related PDCCH resource and at least one set of first synchronization signals; An enabling condition of the random access related PDCCH resource.

29. A random access apparatus, comprising a processing module configured to perform a second operation, the second operation including at least one of the following: Sending a plurality of sets of first synchronization signals; determining or indicating a transmission scheme corresponding to the random access related signal; determining or indicating a time interval between the random access related first downlink signal and the random procedure related first uplink signal; determining or indicating QCL information corresponding to the random access related signal; determining or indicating related information of the random access related PDCCH resource; determining or indicating a power control corresponding to the random access related second uplink signal. 30.A terminal comprising a processor and a memory, the memory storing programs or instructions executable on the processor, the programs or instructions, when executed by the processor, implement steps of the method according to any one of claims 1 to 18. 31.A network side device comprising a processor and a memory, the memory storing programs or instructions executable on the processor, the programs or instructions, when executed by the processor, implement steps of the method according to claim 19. 32.A readable storage medium, the readable storage medium storing programs or instructions, the programs or instructions, when executed by a processor, implement steps of the method according to any one of claims 1 to 19.

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