Communication method, and apparatus

Abstract

The present application provides a communication method and an apparatus. The method comprises: receiving at least two auxiliary synchronization signal and physical broadcast channel blocks (SSBs) from a network device, wherein the at least two auxiliary SSBs are used for at least two reconfigurable intelligence surfaces (RISs) to assist in initial access, and each auxiliary SSB among the at least two auxiliary SSBs corresponds to one RIS among the at least two RISs. By using the embodiment of the present application, in a communication system in which a plurality of RISs are deployed, an RIS auxiliary terminal device performs initial access by means of the auxiliary SSBs, thus reducing the overhead of initial access.

Description

Communication method and device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 2, 2023, with application number 202311452612.X and application name “Communication Method and Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0003] A reconfigurable intelligence surface (RIS) is an ultra-thin metamaterial surface composed of a large number of small, low-cost, and controllable electromagnetic units. Intelligent control circuits dynamically control the characteristics of these units, enabling intelligent control of electromagnetic waves in space. This allows for dynamic configuration of the wireless propagation environment to enhance useful signals and suppress interfering signals. Compared to traditional relays, RIS offers the advantages of low cost and low energy consumption, leading to its widespread application in communications.

[0004] RIS can receive signals from network devices and forward the signals to terminal devices. In a communication system that deploys multiple RIS, how terminal devices perform initial access and reduce initial access overhead are issues that those skilled in the art are currently working on.

[0005] Summary of the Invention

[0006] The present application proposes a communication method and apparatus, which can enable a RIS-assisted terminal device to perform initial access through a secondary SSB in a communication system where multiple RISs are deployed, thereby reducing initial access overhead.

[0007] In a first aspect, an embodiment of the present application provides a communication method, the method comprising: receiving at least two secondary synchronization signals and a physical broadcast channel block (SSB) from a network device, the at least two secondary SSBs being used for at least two smart metasurface RISs to assist in initial access, each of the at least two secondary SSBs corresponding to one of the at least two RISs.

[0008] The method can be applied to a terminal device, including being executed by the terminal device, or by a component in the terminal device (e.g., a processor, chip, or chip system, etc.), or being executed by a logic module or software that can implement all or part of the terminal device functions.

[0009] In the above method, the terminal device receives at least two secondary SSBs from the network device. In scenarios where multiple RISs, such as at least two RISs, are deployed, the RISs assist the terminal device in initial access. Accordingly, the terminal device can perform initial access on one of the at least two secondary SSBs, thereby quickly accessing the network. In this way, terminal devices that can access the network but have poor signal quality can use the RIS to assist in initial access, effectively improving communication quality.

[0010] In a possible implementation, each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0011] In the above method, through the above manner, the terminal device can receive each of the at least two secondary SSBs at the indicated time-frequency resource position or the predefined time-frequency resource position, thereby increasing the possibility of the terminal device receiving the secondary SSB.

[0012] In another possible implementation, the method further includes: receiving a primary SSB from the network device, the primary SSB including first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0013] In the above method, signaling overhead can be saved by including the first configuration information in the main SSB.

[0014] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0015] In the above method, the main SSB includes the first configuration information, which may refer to the main information block MIB carried on the physical broadcast channel PBCH in the main SSB including the first configuration information, or it may be the system message block SIB1 received from the network device, SIB1 including the first configuration information, and the first configuration information includes the configuration information of the SS of each secondary SSB, that is, all the configuration information of the SS of each secondary SSB. By including the first configuration information in the MIB or SIB1, the flexibility and diversity of the method of indicating the first configuration information are increased.

[0016] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; a system message block SIB1 is received from the network device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0017] In the above method, the main SSB includes the first configuration information, which may mean that the main information block MIB carried on the physical broadcast channel PBCH in the main SSB includes the first configuration information, the first configuration information includes partial configuration information of the SS of at least two secondary SSBs, and then SIB1 includes all configuration information except partial configuration information, that is, through the joint indication of MIB and SIB1, the flexibility and diversity of the method of indicating the configuration information of the SS is increased.

[0018] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC, and block error rate BLER threshold.

[0019] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0020] In the above method, signaling overhead can be saved by including the second configuration information in the main SSB.

[0021] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0022] In another possible implementation, the method further includes: detecting the primary SSB to obtain a detection result of the primary SSB, the detection result including one or more of the following: sequence correlation, signal-to-interference-plus-noise ratio (SNR), and received power; when the detection result is lower than a first threshold, determining to perform initial access on one of the at least two secondary SSBs.

[0023] In the above method, the main SSB is detected, and whether to perform initial access is determined based on the detection result. For example, when the SNR is lower than the first threshold, initial access is performed on one of the at least two auxiliary SSBs. That is, whether to perform initial access can be determined based on the signal quality, thereby improving the communication quality. For example, when the received power is lower than the first threshold, initial access is performed on one of the at least two auxiliary SSBs. That is, whether to perform initial access can be determined based on the power consumption of the terminal device, thereby improving the usage time of the terminal device and reducing energy consumption.

[0024] In another possible implementation, the method further includes: detecting each secondary SSB to determine the detection result of each secondary SSB, the detection result of each secondary SSB including one or more of the following: sequence correlation, SNR, and received power; determining the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; and sending the first preamble code on the first RO.

[0025] In a second aspect, an embodiment of the present application provides a communication method, which includes: sending at least two secondary synchronization signals and a physical broadcast channel block (SSB) to a terminal device, wherein the at least two secondary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponds to one of the at least two RISs.

[0026] The method can be applied to network devices, including being executed by the network device, or by components in the network device (e.g., a processor, chip, or chip system, etc.), or by a logic module or software that can implement all or part of the network device functions.

[0027] In a possible implementation, each of the at least two secondary SSBs is sent at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0028] In another possible implementation, a main SSB is sent to the terminal device, and the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0029] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0030] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; a system message block SIB1 is sent to the terminal device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0031] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC or block error rate BLER threshold.

[0032] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0033] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0034] In yet another possible implementation, the method further includes: receiving, on the first RO, a first preamble from the terminal device.

[0035] In another possible implementation, after sending the main SSB to the terminal device, the method further includes: receiving a second preamble code from the terminal device on a second RO corresponding to the main SSB; detecting the second preamble code to obtain a detection result, and the detection result includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; if the detection result is lower than a second threshold, sending indication information to the terminal device, and the indication information is used to instruct the terminal device to perform initial access through the assistance of the RIS.

[0036] In the above method, by detecting the second preamble code and determining the manner of sending the indication information to the terminal device based on the detection result, the network can be better scheduled.

[0037] Regarding the technical effects brought about by the second aspect or possible implementation methods, reference may be made to the introduction to the technical effects of the first aspect or corresponding implementation methods.

[0038] In a third aspect, an embodiment of the present application provides a communication device, which may be a terminal device, or a component in a terminal device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the terminal device, including: a processing unit and a transceiver unit, the transceiver unit being used to receive at least two secondary synchronization signals and a physical broadcast channel block SSB from a network device, the at least two secondary SSBs being used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponding to one of the at least two RISs.

[0039] In a possible implementation, each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0040] In another possible implementation, the transceiver unit is further used to receive a primary SSB from the network device, where the primary SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0041] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0042] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; the transceiver unit is further used to receive a system message block SIB1 from the network device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0043] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC, and block error rate BLER threshold.

[0044] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0045] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0046] In another possible implementation, the processing unit is further used to detect the primary SSB to obtain a detection result of the primary SSB, where the detection result of the primary SSB includes one or more of the following: sequence correlation, signal-to-interference-plus-noise ratio (SNR), and received power; the processing unit is further used to determine, when the detection result is lower than a first threshold, to perform initial access on one of the at least two secondary SSBs.

[0047] In another possible implementation, the processing unit is further used to detect each secondary SSB and determine the detection result of each secondary SSB, and the detection result of each secondary SSB includes one or more of the following: sequence correlation, SNR, and received power; the processing unit is further used to determine the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; the processing unit sends the first preamble code on the first RO through the transceiver unit.

[0048] Regarding the technical effects brought about by the third aspect or possible implementation methods, reference may be made to the introduction to the technical effects of the first aspect or corresponding implementation methods.

[0049] In a fourth aspect, an embodiment of the present application provides a communication device, which may be a network device, or a component in a network device (for example, a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the network device, including: a processing unit and a transceiver unit, the transceiver unit being used to send at least two secondary synchronization signals and a physical broadcast channel block SSB to a terminal device, the at least two secondary SSBs being used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponding to one of the at least two RISs.

[0050] In a possible implementation, each of the at least two secondary SSBs is sent at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0051] In another possible implementation, the transceiver unit is further used to send a main SSB to the terminal device, and the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0052] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0053] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; the transceiver unit is further used to send a system message block SIB1 to the terminal device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0054] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC or block error rate BLER threshold.

[0055] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0056] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0057] In another possible implementation, the transceiver unit is further configured to receive a first preamble from the terminal device on the first RO.

[0058] In another possible implementation, the transceiver unit is further used to receive a second preamble code from the terminal device on a second RO corresponding to the main SSB; the processing unit is further used to detect the second preamble code to obtain a detection result, and the detection result includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; the processing unit is also used to send indication information to the terminal device through the transceiver unit when the detection result is lower than a second threshold, and the indication information is used to instruct the terminal device to perform initial access with the assistance of the RIS.

[0059] Regarding the technical effects brought about by the fourth aspect or possible implementation methods, reference may be made to the introduction to the technical effects of the second aspect or corresponding implementation methods.

[0060] In a fifth aspect, an embodiment of the present application provides a communication device, which includes at least one processor and a communication interface, and the at least one processor is used to call a computer program or instruction stored in a memory to execute the method described in the first aspect or the possible implementation method of the first aspect.

[0061] In a sixth aspect, an embodiment of the present application provides a communication device, which includes at least one processor and a communication interface, and the at least one processor is used to call a computer program or instruction stored in a memory to execute the method described in the above-mentioned second aspect or a possible implementation method in the second aspect.

[0062] In a seventh aspect, an embodiment of the present application provides a chip device, comprising at least one processor, wherein the at least one processor is configured to execute computer programs or instructions to implement the method described in any one of the above aspects.

[0063] In an eighth aspect, an embodiment of the present application provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction runs on a processor, the method described in any one of the above aspects is implemented.

[0064] In a ninth aspect, an embodiment of the present application provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are run on a computer, the method described in any one of the above aspects is implemented.

[0065] In a tenth aspect, an embodiment of the present application provides a communication system, comprising: the apparatus as described in the fifth aspect and the apparatus as described in the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0067] FIG2 is a schematic diagram of a RIS application scenario provided in an embodiment of the present application;

[0068] FIG3 is a schematic diagram of a process for initial access of a terminal device provided in an embodiment of the present application;

[0069] FIG4 is a schematic diagram of an SSB scanning process of a RIS provided in an embodiment of the present application;

[0070] FIG5 is a flow chart of a communication method provided in an embodiment of the present application;

[0071] FIG6 is a schematic diagram of a flow chart of a secondary SSB transmission according to an embodiment of the present application;

[0072] FIG7 is a schematic diagram of another process of sending a secondary SSB according to an embodiment of the present application;

[0073] FIG8 is a schematic diagram of all configuration information of an SS including each secondary SSB in a MIB provided by an embodiment of the present application;

[0074] FIG9 is a schematic diagram of all configuration information of an SS including each secondary SSB in a SIB1 provided by an embodiment of the present application;

[0075] FIG10 is a schematic diagram of configuration information of an SS jointly indicating at least two secondary SSBs provided by an embodiment of the present application using MIB and SIB1;

[0076] FIG11 is a schematic diagram showing a difference between a first RO and a second RO provided in an embodiment of the present application;

[0077] FIG12 is a flow chart of another communication method provided in an embodiment of the present application;

[0078] FIG13 is a flow chart of another communication method provided in an embodiment of the present application;

[0079] FIG14 is a flow chart of another communication method provided in an embodiment of the present application;

[0080] FIG15 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0081] FIG16 is a schematic structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0082] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative efforts are within the scope of protection of this application.

[0083] References to "one embodiment" or "some embodiments" in this application mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0084] In the description of this application, unless otherwise specified, " / " means "or", for example, A / B can mean A or B. "And / or" in this article is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, "at least one" means one or more, and "plurality" means two or more. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c; a and b; a and c; b and c; or a, b, and c. Among them, a, b, and c can be single or multiple.

[0085] It is understood that in this application, "indication" can include direct indication, indirect indication, explicit indication, and implicit indication. When describing that a certain indication information is used to indicate A, it can be understood that the indication information carries A, directly indicates A, or indirectly indicates A.

[0086] In this application, the information indicated by the indication information is referred to as the information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated, such as but not limited to, the information to be indicated can be directly indicated, such as the information to be indicated itself or the index of the information to be indicated, etc., or the information to be indicated can be indirectly indicated by indicating other information, wherein there is an association between the other information and the information to be indicated. It is also possible to indicate only a part of the information to be indicated, while the other parts of the information to be indicated are known or agreed in advance. For example, the indication of specific information can also be achieved with the help of the arrangement order of each information agreed in advance (such as specified in the protocol), thereby reducing the indication overhead to a certain extent.

[0087] The information to be indicated can be sent as a whole or divided into multiple sub-information and sent separately. The transmission period and / or transmission timing of these sub-information can be the same or different. The specific transmission method is not limited in this application. The transmission period and / or transmission timing of these sub-information can be predefined, for example, according to a protocol, or can be configured by the transmitting device through sending configuration information to the receiving device.

[0088] It can be understood that "sending" and "receiving" in this application indicate the direction of signal transmission. For example, "sending information to XX" can be understood as the destination of the information is XX, which can include direct sending through the air interface, and also include indirect sending through the air interface by other units or modules. "Receiving information from YY" can be understood as the source of the information is YY, which can include direct receiving from YY through the air interface, and also include indirect receiving from YY through the air interface from other units or modules. "Sending" can also be understood as the "output" of the chip interface, and "receiving" can also be understood as the "input" of the chip interface.

[0089] In other words, sending and receiving can be performed between devices, for example, between a network device and a terminal device, or can be performed within a device, for example, sending or receiving between components, modules, chips, software modules or hardware modules within the device through a bus, wiring or interface.

[0090] It is understandable that information may be processed between the source and destination of information transmission, such as coding, modulation, etc., but the destination can understand the valid information from the source. Similar expressions in this application can be understood similarly and will not be repeated.

[0091] The communication method provided in the embodiment of the present application can be applied to cellular communication systems related to the third generation partnership project (3GPP), for example, fourth generation (4G) communication systems, such as long term evolution (LTE) communication systems, and can also be applied to fifth generation (5G) communication systems, such as 5G new radio (NR) communication systems, or to various future communication systems, such as sixth generation (6G) communication systems. The method provided in the embodiment of the present application can also be applied to Bluetooth systems, wireless fidelity (WiFi) systems, LoRa systems or Internet of Vehicles systems, communication systems that support the integration of multiple wireless technologies, and device-to-device (D2D) systems. The method provided in the embodiment of the present application can also be applied to satellite communication systems, wherein the satellite communication system can be integrated with the above-mentioned communication system. The wireless communication systems involved in this application also include but are not limited to: narrowband Internet of Things (NB-IoT) system, global system for mobile communications (GSM), enhanced data rate for GSM evolution (EDGE), wideband code division multiple access (WCDMA), code division multiple access 2000 (CDMA2000), or time division-synchronization code division multiple access (TD-SCDMA).

[0092] Please refer to Figure 1, which is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application. The application scenario used in this application is described by taking the communication system architecture shown in Figure 1 as an example. The communication system includes a network device 101, a terminal device 102, and a reconfigurable intelligence surface (RIS) 103. The number of intelligent metasurfaces 103 is at least two, wherein the intelligent metasurface may also be referred to as an intelligent reflection surface (IRS). The apparatus provided in the embodiment of the present application can be applied to the network device 101 and the terminal device 102. It will be understood that Figure 1 only shows a possible communication system architecture that can be applied in the embodiment of the present application. The communication system architecture may include more or fewer network devices, more or fewer terminal devices, or more RIS. In other possible scenarios, the communication system architecture may also include other devices. It should be noted that the method shown in the embodiment of the present application can be applied to the communication system described in Figure 1.

[0093] The network device 101 is a device deployed in a radio access network to provide wireless communication functions for terminal devices. The network device 101 can also be called an access network (RAN) entity, an access node, a network node, or a communication device.

[0094] Specifically, the network device may be an access network device of a cellular system related to the 3rd Generation Partnership Project (3GPP). For example, a fourth-generation (4G) mobile communication system or a 5G mobile communication system. The network device may also be an access network device in an open access network (O-RAN or ORAN) or a cloud radio access network (CRAN). Alternatively, the network device may be an access network device in a communication system obtained by integrating two or more of the above communication systems.

[0095] The network equipment includes, but is not limited to, evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home evolved NodeB, or home Node B, HNB), baseband unit (BBU), access point (AP) in wireless fidelity (WIFI) system, macro base station, micro base station, wireless relay node, donor node, wireless controller in CRAN scenario, wireless backhaul node, transmission point (TP) or transmission and receiving point (TRP). The network equipment can also be an access network equipment in a 5G mobile communication system. For example, a next generation NodeB (gNB) in a new radio (NR) system, a TRP, a TP, or one or a group of antenna panels (including multiple antenna panels) of a base station in a 5G mobile communication system. Alternatively, the network device may also be a network node constituting a gNB or a transmission point. For example, a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU may be configured separately or included in the same network element. For example, a BBU. The RU may be included in a radio frequency device or radio frequency unit. For example, in a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). Alternatively, the network device may also be a server, a wearable device, a vehicle, or an on-board device. For example, in V2X technology, the network device may be a road side unit (RSU).

[0096] It should be noted that in different systems, CU (or CU-CP and CU-UP), DU or RU may have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, CU may also be called an open centralized unit (O-CU) or an open CU, DU may also be called an open distributed unit (O-DU), a centralized unit control plane (CU-CP) may also be called an open centralized unit control plane (O-CU-CP) or an open CU-CP, a centralized unit user plane (CU-UP) may also be called an open centralized unit user plane (O-CU-UP) or an open CU-UP, and RU may also be called an open radio unit (O-RU). This application does not limit this. Any of the CU, CU-CP, CU-UP, DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0097] In some deployments, the CU implements some gNB functions, while the DU implements some gNB functions. For example, the CU implements the functions of the radio resource control (RRC) and packet data convergence protocol (PDCP) layers, while the DU implements the functions of the radio link control (RLC), media access control (MAC), and physical (PHY) layers. Because RRC layer information ultimately becomes PHY layer information, or is converted from PHY layer information, in this architecture, higher-layer signaling, such as RRC layer signaling or PDCP layer signaling, can also be considered to be sent by the DU, or by the DU+RU. It is understood that a network device can be a CU node, a DU node, or a device that includes both a CU node and a DU node. Furthermore, the CU can be classified as a network device in the access network (RAN) or a network device in the core network (CN), without limitation here.

[0098] Optionally, the network device may also be a core network device. The core network device is responsible for access control, registration management, service management, mobility management, etc. of the terminal device accessing the network. The core network device includes, for example, an access and mobility management function (AMF) entity, a session management function (SMF) entity, a user plane function (UPF) entity, etc., which are not listed here one by one. Among them, the AMF entity may be responsible for the access management and mobility management of the terminal; the SMF entity may be responsible for session management, such as user session establishment, etc.; the UPF entity may be a functional entity of the user plane, mainly responsible for connecting to the external network. It should be noted that in this application, the entity may also be referred to as a network element or a functional entity. For example, the AMF entity may also be referred to as an AMF network element or an AMF functional entity. For another example, the SMF entity may also be referred to as an SMF network element or an SMF functional entity, etc.

[0099] It should be noted that the network device can be the device or apparatus shown above, or it can be a component (for example, a chip), module, or unit in the device or apparatus shown above, and this application does not limit it specifically.

[0100] Terminal device 102, also known as user equipment (UE), mobile station (MS), or mobile terminal (MT), is a device that provides voice or data connectivity to a user. Specifically, it includes a device that provides voice to a user, a device that provides data connectivity to a user, or a device that provides both voice and data connectivity to a user. For example, it may include a handheld device with wireless connectivity or a processing device connected to a wireless modem. The terminal device can communicate with the core network via a radio access network (RAN), exchange voice or data with the RAN, or exchange voice and data with the RAN. Currently, terminal devices may include: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MIDs), wearable devices (such as smart watches, smart bracelets, pedometers, etc.), in-vehicle devices (such as cars, bicycles, electric vehicles, airplanes, ships, trains, high-speed trains, etc.), virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, smart home devices (such as refrigerators, televisions, air conditioners, electric meters, etc.), intelligent robots, workshop equipment, wireless terminals in unmanned driving, wireless terminals in remote surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, and flying devices (such as intelligent robots, hot air balloons, drones, airplanes). Terminal devices may also be other devices with terminal functions, for example, a terminal device may also be a device that functions as a terminal in D2D communication.The terminal device may also include vehicle to everything (V2X) terminal equipment, machine-to-machine / machine-type communications (M2M / MTC) terminal equipment, Internet of Things (IoT) terminal equipment, light terminal equipment (light UE), reduced capability UE (REDCAP UE), subscriber unit, subscriber station, mobile station, remote station, access point (AP), remote terminal, access terminal, user terminal, user agent, or user equipment (user device), drone equipment, etc. For example, it may include a mobile phone (or so-called "cellular" phone), a computer with a mobile terminal device, a portable, pocket-sized, handheld, or computer-built-in mobile device, etc. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), and other devices. Also included are limited devices, such as devices with low power consumption, or devices with limited storage capacity, or devices with limited computing power. Examples include information sensing devices such as barcodes, radio frequency identification (RFID), sensors, global positioning systems (GPS), and laser scanners. In this application, terminal devices with wireless transceiver capabilities and chips that can be provided in the aforementioned terminal devices are collectively referred to as terminal devices.

[0101] It should be noted that the terminal device can be a device or apparatus with a chip, or a device or apparatus with integrated circuits, or a chip, module or control unit in the device or apparatus shown above, and this application does not limit this specifically.

[0102] RIS103 is an ultra-thin metamaterial surface composed of a large number of small, low-cost, and controllable electromagnetic units. Intelligent control circuitry dynamically manipulates the characteristics of these units, enabling intelligent control of electromagnetic waves in space. This allows for dynamic configuration of the wireless propagation environment to enhance useful signals and suppress interference. For example, RIS103 can consist of 1024 or more units, each backed by a phase shifter. Compared to traditional repeaters, RIS offers the advantages of low cost and energy consumption. RIS103 can be used to expand the coverage of a wireless communication network. For example, RIS103 can be installed on a large surface, such as an indoor wall or ceiling, or an outdoor building or landmark. Please refer to Figure 2, which is a schematic diagram of a RIS application scenario provided by an embodiment of the present application. When there is an insurmountable obstacle between the network device and the terminal device, the channel between the network device and the terminal device is non-line-of-sight. If the signal propagation environment is single and lacks a reflection path, the signal that the terminal device can receive is very weak. The RIS can manipulate the reflected beam, aim at the terminal device located in the blind spot, and dynamically track it, creating a virtual line of sight (LoS) propagation path between the network device and the terminal device. That is, the RIS can receive the signal of the terminal device and forward it to the network device. Accordingly, the RIS can receive the signal of the network device and forward it to the terminal device, thereby expanding the coverage of the cell.

[0103] In order to better understand the solutions provided by the embodiments of the present application, some terms, concepts or processes involved in the embodiments of the present application are first introduced below.

[0104] 1. Initial access of terminal devices

[0105] Currently, in the NR system, the initial access of the terminal device can be performed through the broadcast synchronization signal and the physical broadcast channel block (synchronization signal and PBCH block, SSB). Please refer to Figure 3, which is a schematic diagram of the process of initial access of a terminal device provided in an embodiment of the present application.

[0106] Step 1: The network device broadcasts the SSB and remaining minimum system information (RMSI).

[0107] Among them, SSB includes the primary synchronization signal (PSS), the secondary synchronization signal (SSS) and the physical broadcast channel (PBCH). Among them, the terminal device can use the PSS for frequency synchronization and the SSS for obtaining cell identification information. The terminal device can obtain the radio frame number and the air interface alignment through the PBCH, as well as obtain the scheduling system information block 1 (SIB1) information. Among them, the PBCH can carry the master information block (MIB).

[0108] RMSI can include SIB1 and other system information (OSI). OSI includes system information block 2 (SIB2) to system information block 9 (SIB9), and SIB1 can be sent through the physical downlink shared channel (PDSCH). Among them, MIB and SIB1 have their own RRC messages "MasterInformationBlock" and "SystemInformationBlock1" respectively, and SIB2 to SIB9 are encapsulated in a general RRC message called "SystemInformation". MIB and SIB1 can be broadcast periodically, while other system information can be triggered by network equipment or broadcast or provided in a dedicated manner based on the request of the terminal device.

[0109] Step 2: The terminal device detects an SSB and decodes the PBCH to determine the timing information.

[0110] The timing information includes an SSB index.

[0111] Step 3: The terminal device obtains the frequency domain location of the RMSI and the time-frequency resource location of the physical downlink control channel (PDCCH) control resource set (CORESET) according to the MIB.

[0112] Among them, the terminal device obtains RMSI information according to the frequency domain position of the RMSI, and obtains random access channel (RACH) configuration information, uplink and downlink initial bandwidth (BWP) configuration information, and physical uplink control channel (PUCCH) configuration information from the RMSI.

[0113] Step 4: The terminal device sends a RACH preamble to the network device on a corresponding random access channel occasion (RO).

[0114] Step 5: The network device receives the physical random access channel (PRACH).

[0115] After receiving the PRACH, the network device obtains the SSB index and determines which beam is most suitable for the terminal device based on the PRACH.

[0116] Step 6: The network device and the terminal device complete the 2-step or 4-step random access process to complete the initial access.

[0117] 2. SSB scanning process of RIS, please refer to Figure 4, which is a schematic diagram of the SSB scanning process of RIS proposed in an embodiment of the present application.

[0118] Step 1: The network device sends SSB 1 to the RIS.

[0119] The communication link between the network device and the RIS may be referred to as a backhaul link.

[0120] The network device sends M beams to the RIS, where M is a positive integer, and the M beams include SSB1.

[0121] Step 2: RIS continuously sends N beams to the terminal device under each of the M beams.

[0122] The M*N beams include SSB 1. The communication link between the RIS and the terminal device may be referred to as an access link.

[0123] Step 3: The terminal device continuously scans M*N beams to obtain SSB1.

[0124] Therefore, the terminal device needs to scan N*M times in total to obtain the SSB1 sent by the network device. Compared with when the terminal device and the network device are connected, the terminal device continuously scans M beams and needs to scan M times to obtain the SSB, and the scanning time is prolonged.

[0125] Due to the introduction of RIS, when there are multiple RIS, the access overhead will increase. In order to solve the above problem, the embodiment of the present application proposes the following solution.

[0126] Please refer to FIG5 , which is a flow chart of a communication method provided in an embodiment of the present application. The method includes but is not limited to the following steps:

[0127] Step S501: The network device sends at least two secondary SSBs to the terminal device.

[0128] The network device may send at least two secondary SSBs to the terminal device via at least two RISs.

[0129] Step S502: The terminal device receives at least two secondary SSBs from the network device.

[0130] The terminal device may receive at least two secondary SSBs from the network device via at least two RISs.

[0131] The at least two secondary SSBs are used by at least two RISs to assist in initial access. That is, the at least two secondary SSBs are used by at least two RISs to assist terminal devices in initial access. Optionally, the secondary SSBs may be referred to as secondary SSBs.

[0132] Each of the at least two secondary SSBs corresponds to one of the at least two RISs, that is, each of the at least two secondary SSBs has a one-to-one correspondence with each of the at least two RISs. In one example, the at least two secondary SSBs include secondary SSB1 and secondary SSB2, and the at least two RISs include RIS1 and RIS2. The network device sends secondary SSB1 and secondary SSB2 to the terminal device, wherein secondary SSB1 and secondary SSB2 correspond to RIS1 and RIS2, respectively, that is, secondary SSB1 corresponds to RIS1, and secondary SSB2 corresponds to RIS2.

[0133] Among them, each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, that is, the terminal device can receive each of the at least two secondary SSBs at the corresponding time-frequency resource position of each of the at least two secondary SSBs. The time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position. Optionally, the predefined time-frequency resource position can be understood as defining a set of possible frequency positions for the secondary SSB based on the frequency band, which is called a synchronization grid. Accordingly, the terminal device can search for the secondary SSB on the synchronization grid. Accordingly, through the above method, the possibility of the terminal device receiving the secondary SSB can be improved.

[0134] In one example, the at least two secondary SSBs include secondary SSB1 and secondary SSB2. The terminal device receives secondary SSB1 at time-frequency resource position 1 corresponding to secondary SSB1 and receives secondary SSB2 at time-frequency resource position 2 corresponding to secondary SSB2. Optionally, refer to FIG6 , which is a schematic diagram of a secondary SSB transmission process provided by an embodiment of the present application. The time domain resources corresponding to time-frequency resource position 1 do not overlap with the time domain resources corresponding to time-frequency resource position 2, but the frequency domain resources corresponding to time-frequency resource position 1 overlap with the frequency domain resources corresponding to time-frequency resource position 2. In this case, the network device can use the beam corresponding to each RIS to send at least two secondary SSBs to the RIS in time-sharing. For example, the network device sends secondary SSB1 to RIS1 using beam 0 and sends secondary SSB2 to RIS2 using beam 1. Accordingly, different RISs perform scanning in time-sharing. RIS1 performs beam scanning on time domain resource 1 to reflect secondary SSB1, and RIS2 performs beam scanning on time domain resource 2 to reflect secondary SSB2. Optionally, please refer to Figure 7, which is a schematic diagram of another process of sending a secondary SSB provided by an embodiment of the present application. The time domain resources corresponding to time-frequency resource position 1 overlap with the time domain resources corresponding to time-frequency resource position 2, but the frequency domain resources corresponding to time-frequency resource position 1 do not overlap with the frequency domain resources corresponding to time-frequency resource position 2. In this case, the network device can use a fixed beam to send at least two secondary SSBs to the RIS on the frequency domain resources corresponding to different RISs. For example, the network device sends secondary SSB1 to RIS1 using beam 0 on frequency domain resource 1, and sends secondary SSB2 to RIS2 using beam 1 on frequency domain resource 2. Accordingly, different RISs perform frequency division scanning, RIS1 performs beam scanning on frequency domain resource 1 to reflect secondary SSB1, and RIS2 performs beam scanning on frequency domain resource 2 to reflect secondary SSB2.

[0135] In one possible implementation, the network device sends a primary SSB to the terminal device, and accordingly, the terminal device receives the primary SSB from the network device. Optionally, before the terminal device receives at least two secondary SSBs from the network device, the terminal device receives the primary SSB from the network device.

[0136] Optionally, the network device may send the primary SSB to the terminal device by broadcasting. Optionally, the primary SSB may be called a mandatory SSB.

[0137] The primary SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB, that is, the time-frequency resource position corresponding to each secondary SSB is the indicated time-frequency resource position. Accordingly, the terminal device can determine the time-frequency resource position corresponding to each secondary SSB based on the first configuration information. The first configuration information may include the configuration information of the synchronization signal (synchronous signal, SS) of each secondary SSB, that is, all configuration information of the SS of each secondary SSB, or the first configuration information may include partial configuration information of the SS of the at least two secondary SSBs. For example, all configuration information or partial configuration information may be a time-frequency resource position, sequence type, basic frequency point, etc., as follows:

[0138] The first configuration information may include all configuration information of the SS of each secondary SSB. Optionally, the main SSB including the first configuration information may refer to the MIB carried on the PBCH in the main SSB including the first configuration information, that is, the MIB including all configuration information of the SS of each secondary SSB, please refer to Figure 8, Figure 8 is a schematic diagram of a MIB provided in an embodiment of the present application including all configuration information of the SS of each secondary SSB, the main SSB including the first configuration information may also refer to the terminal device receiving the SIB1 from the network device, the SIB1 including the first configuration information, that is, the SIB1 including all configuration information of the SS of each secondary SSB, please refer to Figure 9, Figure 9 is a schematic diagram of a SIB1 provided in an embodiment of the present application including all configuration information of the SS of each secondary SSB, and the embodiment of the present application does not limit it.

[0139] The first configuration information includes partial configuration information of the SSs of the at least two secondary SSBs. The terminal device may receive SIB1 from the network device. The SIB1 includes configuration information other than the partial configuration in all configuration information of the SSs of the at least two secondary SSBs. Specifically, the following two situations may be included:

[0140] The first case: assuming that the at least two secondary SSBs include secondary SSB1 and secondary SSB2, all configuration information of the SS of secondary SSB1 includes configuration information 1 and configuration information 2, and all configuration information of the SS of secondary SSB2 includes configuration information 3 and configuration information 4, then the first configuration information may include partial configuration information of the SS of secondary SSB1, such as configuration information 1, and partial configuration information of the SS of secondary SSB2, such as configuration information 3. Correspondingly, SIB1 may include the remaining partial configuration information of the SS of secondary SSB1, namely configuration information 2, and the remaining partial configuration information of the SS of secondary SSB2, namely configuration information 4.

[0141] The second case: assuming that the at least two secondary SSBs include secondary SSB1 and secondary SSB2, the first configuration information includes partial configuration information of the SSs of secondary SSB1 and secondary SSB2, and the partial configuration information can be understood as the content of the characteristics commonly shared by the configuration information of the SS of secondary SSB1 and the configuration information of the SS of secondary SSB2, for example, it can be referred to as configuration information 5, and SIB1 includes configuration information 6 and configuration information 7, wherein configuration information 6 is the configuration information of all configuration information of the SS of secondary SSB1 except for configuration information 5, that is, the content of the common characteristics, and configuration information 7 is the configuration information of all configuration information of the SS of secondary SSB2 except for configuration information 5, that is, the content of the common characteristics.

[0142] In the above two cases, the primary SSB includes the first configuration information, and the first configuration information includes partial configuration information of the SS of at least two secondary SSBs, which may refer to the MIB carried on the PBCH in the primary SSB including the first configuration information, that is, the MIB includes partial configuration information of the SS of the at least two secondary SSBs, wherein the partial configuration information of the SS of the at least two secondary SSBs can be referred to as the first part of all configuration information, and the MIB may further include indication information, which is used to indicate the time-frequency resource position corresponding to the configuration information other than the partial configuration information in all configuration information in SIB1, wherein the configuration information other than the partial configuration information in all configuration information can be referred to as the second part of information, that is, The indication information is used to indicate the time-frequency resource position corresponding to the second part of the information in SIB1. Accordingly, the terminal device determines the first part of the information based on the MIB, and the SIB1 received from the network device can determine the time-frequency resource position corresponding to the second part of the information in SIB1 according to the indication information in the MIB, thereby determining the second part of the information, that is, the configuration information of the SS of at least two secondary SSBs is jointly indicated by the MIB and SIB1. Please refer to Figure 10. Figure 10 is a schematic diagram of the configuration information of the SS of at least two secondary SSBs jointly indicated by the MIB and SIB1 provided in an embodiment of the present application, wherein SIB1 is carried on the PDSCH, and the PDSCH requires the physical downlink control information (physical Downlink control channel (DCI) scheduling, accordingly, after successful MIB decoding, the terminal device determines the first part of the information from the MIB, and the terminal device can also obtain information about the control resource set (CORSET0) and PDCCH search space required for SIB1 decoding, and then obtains DCI from PDCCH, and then determines PDSCH based on the DCI, thereby determining SIB1, and determining the second part of the information from SIB1, and obtaining all configuration information of the SS of at least two secondary SSBs based on MIB and SIB1.

[0143] Optionally, one or more of the following parameters of the PDSCH used to carry SIB1 may be the same as those of the PBCH and / or PDCCH, including: a coding mode, adaptive modulation and coding (AMC), and a block error rate (BLER) threshold. Optionally, the coding mode may include polar codes, AMC may include a low-order modulation mode and a low coding rate, and the BLER threshold may be relatively small.

[0144] Optionally, the primary SSB includes second configuration information, which is the first random access channel opportunity (RO) corresponding to each secondary SSB. The second configuration information includes one or more of the following: the sequence of the first preamble code corresponding to the first RO, the cyclic shift of the first preamble code corresponding to the first RO, and the time-frequency domain position corresponding to the first RO. Optionally, the first RO corresponding to each secondary SSB may be different from the second RO corresponding to the primary SSB. Please refer to Figure 11. Figure 11 is a schematic diagram of a first RO and a second RO different from each other provided in an embodiment of the present application. Specifically, it may include one or more of the following: the sequence of the first preamble code corresponding to the first RO may be different from the sequence of the second preamble code corresponding to the second RO, the cyclic shift of the first preamble code corresponding to the first RO is different from the cyclic shift of the second preamble code corresponding to the second RO, and the time-frequency domain position corresponding to the first RO is different from the time-frequency domain position corresponding to the second RO. Optionally, the sequence of the first preamble code corresponding to the first RO may be a Golden sequence and / or an M sequence, which is not limited in the embodiment of the present application. The sequence of the second preamble code corresponding to the second RO may be a Zadoff–Chu sequence, i.e., a ZC sequence. The time-frequency domain position corresponding to the first RO is different from the time-frequency domain position corresponding to the second RO, which can be understood as the first RO corresponding to time-frequency domain position 1, and the second RO corresponding to time-frequency domain position 2, wherein the time-frequency domain resources corresponding to time-frequency domain position 1 are not exactly the same as the time-frequency domain resources corresponding to time-frequency domain position 2. For example, the time domain resources corresponding to time-frequency domain position 1 are the same as the time domain resources corresponding to time-frequency domain position 2, but the frequency domain resources are different; the time domain resources corresponding to time-frequency domain position 1 are different from the time domain resources corresponding to time-frequency domain position 2, but the frequency domain resources are the same; the time domain resources corresponding to time-frequency domain position 1 are different from the time domain resources corresponding to time-frequency domain position 2, and the frequency domain resources are different.

[0145] In another possible implementation, the terminal device detects the primary SSB and obtains a detection result of the primary SSB. When the detection result of the primary SSB is lower than a first threshold, it is determined to perform initial access on one of the at least two secondary SSBs.

[0146] Optionally, after receiving the main SSB from the network device, the terminal device detects the main SSB to obtain a detection result. The detection result includes sequence correlation, SNR, and receiving power. Sequence correlation refers to the sum of the correlations between the sequence of the SS in the main SSB and the sequence on the terminal device side at multiple times. SNR refers to the ratio between the SS of the received main SSB and the noise. Received power refers to the power of the SS of the received main SSB. Optionally, the first threshold can be determined by the terminal device, the network device, or agreed upon by the protocol, and is not limited in the embodiment of the present application. When the detection result of the main SSB is lower than the first threshold, it is determined to perform initial access on one of the at least two secondary SSBs, that is, initial access is not performed on the main SSB.

[0147] In the above method, the main SSB is detected, and whether to perform initial access is determined based on the detection result. For example, when the SNR is lower than the first threshold, initial access is performed on one of the at least two auxiliary SSBs. That is, whether to perform initial access can be determined based on the signal quality, thereby improving the communication quality. For example, when the received power is lower than the first threshold, initial access is performed on one of the at least two auxiliary SSBs. That is, whether to perform initial access can be determined based on the power consumption of the terminal device, thereby improving the usage time of the terminal device and reducing energy consumption.

[0148] In another possible implementation, the terminal device detects each secondary SSB to determine the detection result of each secondary SSB, and determines the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; the first preamble code is sent on the first RO, and accordingly, the network device can receive the first preamble code from the terminal device on the first RO.

[0149] Among them, the detection result of each secondary SSB includes one or more of the following: sequence correlation, SNR, and received power. For details, please refer to the above. The second configuration information is the first random access channel opportunity corresponding to each secondary SSB, which can be understood as the second configuration information being used to indicate the configuration of possible ROs corresponding to all RISs. The terminal device detects each secondary SSB, which can mean that after determining the time-frequency resource position corresponding to each secondary SSB based on the first configuration information, the terminal device can blindly detect each secondary SSB at the time-frequency resource position corresponding to each secondary SSB, and select the best SS for synchronization and decoding PBCH. Since the terminal device has at least two RISs to choose from, it can only select the best one of the RISs at a time to assist in initial access, that is, select the best SS among the secondary SSBs corresponding to the best RIS. The best can be understood as the one with the best synchronization performance. Optionally, the sequence correlation, SNR, received power, and other indicators in the detection results of each secondary SSB can be used to determine whether the synchronization performance is optimal, that is, determine the SS with the best synchronization performance, and thus the best RIS corresponding to the secondary SSB of the SS with the best synchronization performance. Since the second configuration information is used to indicate the configuration of possible ROs corresponding to all RISs, the first RO can be determined based on the best RIS corresponding to the secondary SSB of the SS with the best synchronization performance and the second configuration information. The terminal device sending the first preamble on the first RO can be understood as the terminal device sending the corresponding first preamble to the network device on the first RO via the selected best RIS. Accordingly, the network device can receive the corresponding first preamble from the terminal device on the first RO via the RIS.

[0150] In another possible implementation, after the network device sends the main SSB to the terminal device, the network device can also receive a second preamble code from the terminal device on the second RO corresponding to the main SSB, detect the second preamble code to obtain a detection result, and if the detection result is lower than the second threshold, send an indication information to the terminal device.

[0151] Optionally, the SIB1 received by the terminal device may include third configuration information, which may be configuration information of a second RO corresponding to the primary SSB. The third configuration information may include one or more of the following: a sequence of a second preamble corresponding to the second RO, a cyclic shift of the second preamble corresponding to the second RO, and a time-frequency domain position corresponding to the second RO. Accordingly, the terminal device may determine the second RO based on the third configuration information and send the second preamble to the network device on the second RO.

[0152] The detection result includes sequence correlation, SNR, and received power. Sequence correlation refers to the sum of correlations between the sequence constituting the second preamble and the sequence on the network device at multiple times. SNR refers to the ratio of the received second preamble to noise. Received power refers to the power of receiving the second preamble.

[0153] Optionally, the second threshold may be determined by a terminal device, a network device, or specified by a protocol, and is not limited in the embodiments of the present application.

[0154] Optionally, the indication information is used to instruct the terminal device to perform initial access through the assistance of RIS, and the indication information can be carried in message 2 (Msg2). Optionally, before the network device sends the indication information to the terminal device, the network device needs to determine the access status of different terminal devices, that is, whether the terminal device performs initial access through the main SSB or the auxiliary SSB. The network device can determine the access status of different terminal devices based on the second configuration information. That is, if the terminal device performs initial access through the configuration of the first RO indicated in the second configuration information, the terminal device needs to perform initial access through the auxiliary SSB; if the terminal device performs initial access through the configuration of the second RO indicated in the third configuration information, the terminal device needs to perform initial access through the main SSB.

[0155] In the above method, by detecting the second preamble code and determining the manner of sending the indication information to the terminal device based on the detection result, the network can be better scheduled.

[0156] In another possible implementation, before the terminal device receives the secondary SSB from the network device, the terminal device does not detect the primary SSB sent by the network device, and access fails.

[0157] In the method described in FIG. 5 , a terminal device receives at least two secondary SSBs from a network device. In a scenario where multiple RISs, such as at least two RISs, are deployed, the RISs assist the terminal device in initial access. Accordingly, the terminal device can perform initial access on one of the at least two secondary SSBs, thereby quickly accessing the network. In this manner, a terminal device that can access the network but has a poor signal quality can perform initial access with the assistance of the RIS, effectively improving communication quality.

[0158] Please refer to FIG12, which is a flowchart of another communication method provided in an embodiment of the present application. The method includes but is not limited to the following steps:

[0159] Step S1201: The network device sends a main SSB to the terminal device.

[0160] Optionally, before the network device sends the main SSB to the terminal device, at least two RISs perform initial access through the main SSB, that is, the at least two RISs have already accessed the network. Optionally, the network device can send the main SSB to the terminal device by broadcasting.

[0161] Step S1202: The terminal device receives the main SSB from the network device.

[0162] Among them, the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB of at least two secondary SSBs. The first configuration information includes the configuration information of the SS of each secondary SSB. The first configuration information includes partial configuration information of the SS of at least two secondary SSBs, and the terminal device can also receive SIB1 from the network device, and the SIB1 includes all configuration information of the SS of at least two secondary SSBs except the partial configuration information. One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 can be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH. The following one or more items include: coding mode, AMC, and BLER threshold value. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0163] The primary SSB includes second configuration information, which is configuration information of the RO corresponding to each secondary SSB. The second configuration information includes one or more of the following: a sequence of the first preamble corresponding to the first RO, a cyclic shift of the first preamble corresponding to the first RO, and a time-frequency domain position corresponding to the first RO. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0164] Step S1203: The terminal device detects the primary SSB and obtains a detection result. When the detection result is lower than a first threshold, it determines to perform initial access on one of the at least two secondary SSBs.

[0165] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0166] Step S1204: The network device sends at least two secondary SSBs to the terminal device.

[0167] The network device may send at least two secondary SSBs to the terminal device via at least two RISs.

[0168] Step S1205: The terminal device receives at least two secondary SSBs from the network device.

[0169] The terminal device may receive at least two secondary SSBs from the network device via at least two RISs.

[0170] The at least two auxiliary SSBs are used to assist the at least two smart metasurface RISs in initial access, and each of the at least two auxiliary SSBs corresponds to one of the at least two RISs. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0171] Step S1206: The terminal device detects each secondary SSB to determine a detection result of each secondary SSB, and determines a first RO and a first preamble code based on the second configuration information and the detection result of each secondary SSB.

[0172] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0173] Step S1207: The terminal device sends a first preamble code to the network device on the first RO.

[0174] The terminal device may send the first preamble code to the network device on the first RO through the RIS.

[0175] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0176] Step S1208: The network device receives a first preamble from the terminal device on the first RO.

[0177] In the method described in FIG12 , a terminal device receives at least two secondary SSBs from a network device. In a scenario where multiple RISs, such as at least two RISs, are deployed, the RIS assists the terminal device in initial access. Accordingly, the terminal device can perform initial access on one of the at least two secondary SSBs, thereby quickly accessing the network. In this manner, a terminal device that can access the network but has a poor signal quality can perform initial access with the assistance of the RIS, effectively improving communication quality.

[0178] Please refer to FIG13, which is a flowchart of another communication method provided in an embodiment of the present application. The method includes but is not limited to the following steps:

[0179] Step S1301: The network device sends a main SSB to the terminal device.

[0180] Optionally, before the network device sends the main SSB to the terminal device, at least two RISs perform initial access through the main SSB, that is, the at least two RISs have already accessed the network.

[0181] Step S1302: The terminal device receives the main SSB from the network device.

[0182] Among them, the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB of at least two secondary SSBs. The first configuration information includes the configuration information of the SS of each secondary SSB. The first configuration information includes partial configuration information of the SS of at least two secondary SSBs, and the terminal device can also receive SIB1 from the network device, and the SIB1 includes all configuration information of the SS of at least two secondary SSBs except the partial configuration information. One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 can be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH. The following one or more items include: coding mode, AMC, and BLER threshold value. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0183] The primary SSB includes second configuration information, which is configuration information of the RO corresponding to each secondary SSB. The second configuration information includes one or more of the following: a sequence of the first preamble corresponding to the first RO, a cyclic shift of the first preamble corresponding to the first RO, and a time-frequency domain position corresponding to the first RO. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0184] Step S1303: The terminal device detects the main SSB and determines the time-frequency resource position corresponding to each of the at least two secondary SSBs based on the first configuration information.

[0185] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0186] Step S1304: The terminal device sends a second preamble code to the network device on the second RO corresponding to the main SSB.

[0187] Optionally, the SIB1 received by the terminal device may include third configuration information, which may be configuration information of the second RO corresponding to the primary SSB. The third configuration information may include one or more of the following: a sequence of the second preamble corresponding to the second RO, a cyclic shift of the second preamble corresponding to the second RO, and a time-frequency domain position corresponding to the second RO. Accordingly, the terminal device may determine the second RO based on the third configuration information and send the second preamble to the network device on the second RO. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0188] Step S1305: The network device receives a second preamble code from the terminal device on the second RO corresponding to the primary SSB.

[0189] Step S1306: The network device detects the second preamble code to obtain a detection result. If the detection result is lower than the second threshold, an indication message is sent to the terminal device.

[0190] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0191] Step S1307: The network device sends message 2 (Msg2) to the terminal device.

[0192] Among them, the message 2 includes indication information, and the indication information is used to instruct the terminal device to perform initial access through the assistance of RIS. Optionally, before the network device sends the indication information to the terminal device, the network device needs to determine the access status of different terminal devices, that is, whether the terminal device performs initial access through the main SSB or the auxiliary SSB. Among them, the network device can determine the access status of different terminal devices based on the second configuration information. That is, if the terminal device performs initial access through the configuration of the first RO indicated in the second configuration information, the terminal device needs to perform initial access through the auxiliary SSB; if the terminal device performs initial access through the configuration of the second RO indicated in the third configuration information, the terminal device needs to perform initial access through the main SSB.

[0193] Step S1308: The terminal device receives message 2 from the network device.

[0194] Step S1309: The network device sends at least two secondary SSBs to the terminal device.

[0195] The network device may send at least two secondary SSBs to the terminal device via at least two RISs.

[0196] Step S1310: The terminal device receives at least two secondary SSBs from the network device.

[0197] The terminal device may receive at least two secondary SSBs from the network device via at least two RISs.

[0198] The at least two auxiliary SSBs are used to assist the at least two smart metasurface RISs in initial access, and each of the at least two auxiliary SSBs corresponds to one of the at least two RISs. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0199] Step S1311: The terminal device detects each secondary SSB to determine a detection result of each secondary SSB, and determines a first RO and a first preamble code based on the second configuration information and the detection result of each secondary SSB.

[0200] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0201] Step S1312: The terminal device sends a first preamble code to the network device on the first RO.

[0202] The terminal device may send the first preamble code to the network device on the first RO through the RIS.

[0203] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0204] Step S1313: The network device receives a first preamble from the terminal device on the first RO.

[0205] The network device may receive the first preamble code of the terminal device on the first RO through the RIS.

[0206] In the method described in FIG13 , a terminal device receives at least two secondary SSBs from a network device. In a scenario where multiple RISs, such as at least two RISs, are deployed, the RISs assist the terminal device in initial access. Accordingly, the terminal device can perform initial access on one of the at least two secondary SSBs, thereby quickly accessing the network. In this manner, a terminal device that can access the network but has a poor signal quality can perform initial access with the assistance of the RIS, effectively improving communication quality.

[0207] Please refer to FIG14, which is a flowchart of another communication method provided in an embodiment of the present application. The method includes but is not limited to the following steps:

[0208] Step S1401: The network device sends a main SSB to the terminal device.

[0209] Optionally, before the network device sends the main SSB to the terminal device, at least two RISs perform initial access through the main SSB, that is, the at least two RISs have already accessed the network.

[0210] Among them, the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB of at least two secondary SSBs. The first configuration information includes the configuration information of the SS of each secondary SSB. The first configuration information includes partial configuration information of the SS of at least two secondary SSBs, and the terminal device can also receive SIB1 from the network device, and the SIB1 includes all configuration information of the SS of at least two secondary SSBs except the partial configuration information. One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 can be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH. The following one or more items include: coding mode, AMC, and BLER threshold value. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0211] The primary SSB includes second configuration information, which is configuration information of the RO corresponding to each secondary SSB. The second configuration information includes one or more of the following: a sequence of the first preamble corresponding to the first RO, a cyclic shift of the first preamble corresponding to the first RO, and a time-frequency domain position corresponding to the first RO. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0212] Step S1402: The terminal device does not detect the main SSB and access fails.

[0213] Step S1403: The network device sends at least two secondary SSBs to the terminal device.

[0214] The network device may send at least two secondary SSBs to the terminal device via at least two RISs.

[0215] The at least two auxiliary SSBs are used to assist the at least two smart metasurface RISs in initial access, and each of the at least two auxiliary SSBs corresponds to one of the at least two RISs. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0216] Step S1404: The terminal device detects each secondary SSB at the corresponding time-frequency resource position of each secondary SSB in at least two secondary SSBs.

[0217] Among them, the terminal device detects each secondary SSB at the corresponding time-frequency resource position of each secondary SSB of the at least two secondary SSBs, which can be understood as the terminal device blindly detecting each secondary SSB at the possible time-frequency resource position (synchronization grid) corresponding to each secondary SSB, and selecting the best SS for synchronization and decoding the PBCH. For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0218] Step S1405: The terminal device sends a first preamble code to the network device on the first RO.

[0219] The terminal device may send the first preamble code to the network device on the first RO through the RIS.

[0220] For details, please refer to the relevant description in the above step S502, which will not be repeated here.

[0221] Step S1406: The network device receives a first preamble from the terminal device on the first RO.

[0222] In the method described in FIG14 , a terminal device receives at least two secondary SSBs from a network device. In a scenario where multiple RISs, such as at least two RISs, are deployed, the RISs assist the terminal device in initial access. Accordingly, the terminal device can perform initial access on one of the at least two secondary SSBs, thereby quickly accessing the network. In this manner, a terminal device that can access the network but has a poor signal quality can perform initial access with the assistance of the RIS, effectively improving communication quality.

[0223] The above describes in detail the method of the embodiment of the present application, and the following provides an apparatus of the embodiment of the present application.

[0224] Please refer to FIG. 15 , which is a schematic diagram of the structure of a communication device 1500 provided in an embodiment of the present application. The communication device 1500 may include a processing unit 1501 and a transceiver unit 1502 . The details of each unit are as follows:

[0225] Processing unit 1501 is used to perform data processing. Transceiver unit 1502 can implement corresponding communication functions. Transceiver unit 1502 can also be called a communication interface or communication module. Optionally, processing unit 1501 can be implemented by at least one processor or processor-related circuit.

[0226] Optionally, the communication device 1500 may further include a storage unit, which may be used to store instructions and / or data. The processing unit 1501 may read the instructions and / or data in the storage module to implement the aforementioned method embodiment.

[0227] Optionally, the transceiver unit 1502 may include a transmitting unit and a receiving unit. The transmitting unit is configured to perform the transmitting operation in the above method embodiment. The receiving unit is configured to perform the receiving operation in the above method embodiment. Optionally, the transceiver unit 1502 may be implemented by a transceiver or transceiver-related circuits.

[0228] It should be noted that the communication device 1500 may include a sending unit but not a receiving unit. Alternatively, the communication device 1500 may include a receiving unit but not a sending unit. The specific implementation depends on whether the above solution executed by the communication device 1500 includes a sending action and a receiving action.

[0229] Optionally, the communication device 1500 can be used to perform the actions performed by the terminal device in the above method embodiment. The communication device 1500 can be a terminal device or a component that can be configured in the terminal device (for example, a processor, a chip, or a chip system). For example, the communication device 1500 is used to perform the following scheme:

[0230] The transceiver unit 1502 is used to receive at least two secondary synchronization signals and a physical broadcast channel block (SSB) from a network device. The at least two secondary SSBs are used by at least two smart metasurface RISs to assist in initial access. Each of the at least two secondary SSBs corresponds to one of the at least two RISs.

[0231] In a possible implementation, each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0232] In another possible implementation, the transceiver unit 1502 is further used to receive a primary SSB from the network device, where the primary SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0233] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0234] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; the transceiver unit 1502 is further used to receive a system message block SIB1 from the network device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0235] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC, and block error rate BLER threshold.

[0236] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0237] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0238] In another possible implementation, the processing unit 1501 is further used to detect the primary SSB to obtain a detection result of the primary SSB, where the detection result of the primary SSB includes one or more of the following: sequence correlation, signal-to-interference-plus-noise ratio (SNR), and received power; the processing unit 1501 is further used to determine, when the detection result is lower than a first threshold, to perform initial access on one of the at least two secondary SSBs.

[0239] In another possible implementation, the processing unit 1501 is further used to detect each secondary SSB to determine the detection result of each secondary SSB, and the detection result of each secondary SSB includes one or more of the following: sequence correlation, SNR, and received power; the processing unit 1501 is further used to determine the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; the processing unit 1501 sends the first preamble code on the first RO through the transceiver unit 1502.

[0240] It should be noted that the implementation and beneficial effects of each module may also correspond to the corresponding description of the method embodiment shown in Figure 5, Figure 12, Figure 13 or Figure 14.

[0241] Optionally, the communication device 1500 can be used to perform the actions performed by the network device in the above method embodiment. The communication device 1500 can be a network device or a component that can be configured in a network device (for example, a processor, a chip, or a chip system). For example, the communication device 1500 is used to perform the following scheme:

[0242] The transceiver unit 1502 is used to send at least two secondary synchronization signals and a physical broadcast channel block SSB to the terminal device, where the at least two secondary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponds to one of the at least two RISs.

[0243] In a possible implementation, each of the at least two secondary SSBs is sent at a corresponding time-frequency resource position, where the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

[0244] In another possible implementation, the transceiver unit 1502 is further used to send a main SSB to the terminal device, where the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

[0245] In another possible implementation, the first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

[0246] In another possible implementation, the first configuration information includes partial configuration information of the SS of the at least two secondary SSBs; the transceiver unit 1502 is further used to send a system message block SIB1 to the terminal device, and the SIB1 includes configuration information of all configuration information of the SS of the at least two secondary SSBs except the partial configuration information.

[0247] In another possible implementation, one or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC or block error rate BLER threshold.

[0248] In another possible implementation, the primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

[0249] In another possible implementation, the second configuration information includes one or more of the following: a sequence of the first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

[0250] In another possible implementation, the transceiver unit 1502 is further configured to receive a first preamble from the terminal device on the first RO.

[0251] In another possible implementation, the transceiver unit 1502 is further used to receive a second preamble code from the terminal device on a second RO corresponding to the primary SSB; the processing unit 1501 is further used to detect the second preamble code to obtain a detection result, and the detection result includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; the processing unit 1501 is also used to send indication information to the terminal device through the transceiver unit 1502 when the detection result is lower than a second threshold, and the indication information is used to instruct the terminal device to perform initial access with the assistance of the RIS.

[0252] It should be noted that the implementation and beneficial effects of each module may also correspond to the corresponding description of the method embodiment shown in Figure 5, Figure 12, Figure 13 or Figure 14.

[0253] It should be understood that the specific process of each module executing the above corresponding process has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

[0254] Please refer to Figure 16, which is a schematic diagram of the structure of another communication device 1600 provided in an embodiment of the present application. The communication device 1600 includes at least one processor 1601 and a communication interface 1603, and optionally also includes a memory 1602. The processor 1601, memory 1602, and communication interface 1603 are interconnected via a bus 1604. Optionally, the memory 1602 may also be integrated with the processor 1601.

[0255] Memory 1602 includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or compact disc read-only memory (CD-ROM), and is used to store relevant computer programs and data. Communication interface 1603 is used to receive and send data.

[0256] The processor 1601 may be one or more central processing units (CPUs). When the processor 1601 is a CPU, the CPU may be a single-core CPU or a multi-core CPU.

[0257] The processor 1601 in the communication device 1600 is used to read the computer program or instructions stored in the memory 1602 to implement the functions of the above-mentioned processing unit, and the communication interface 1603 in the communication device 1600 is used to implement the functions of the above-mentioned transceiver unit.

[0258] An embodiment of the present application also provides a chip device, which includes at least one processor, and the at least one processor is used to call a computer program or instruction stored in a memory so that the processor executes the method provided by the embodiment shown in Figures 5, 12, 13 or 14 above.

[0259] An embodiment of the present application also provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction runs on a processor, the method provided in the embodiment shown in Figures 5, 12, 13 or 14 above is executed.

[0260] An embodiment of the present application also provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are run on a processor, the method provided in the embodiment shown in Figure 5, Figure 12, Figure 13 or Figure 14 above is executed.

[0261] The present application also provides a communication system including the terminal device and the network device described in the above embodiment. The terminal device is configured to perform some or all of the operations performed by the terminal device in the above method embodiment, and the network device is configured to perform some or all of the operations performed by the network device in the above method embodiment.

[0262] It is understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0263] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an erasable programmable read-only memory, an electrically erasable programmable read-only memory, a register, a hard disk, a mobile hard disk, a CD-ROM or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a base station or a terminal. Of course, the processor and the storage medium can also exist in a base station or a terminal as discrete components.

[0264] In the above embodiments, all or part of the embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are performed in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable device. The computer program or instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; an optical medium, such as a digital video disk; or a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or nonvolatile storage medium, or may include both volatile and nonvolatile types of storage media.

[0265] In the various embodiments of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0266] In the description of this application, words such as "first", "second", "S501", or "S502" are only used to distinguish the description and facilitate the context. Different sequence numbers themselves do not have specific technical meanings and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying the order of execution of operations. The execution order of each process should be determined by its function and internal logic.

[0267] In this application, the term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. A and B can be singular or plural. Additionally, the character " / " in this document indicates that the related objects are in an "or" relationship.

[0268] In this application, "transmission" may include the following three situations: sending of data, receiving of data, or sending of data and receiving of data. In this application, "data" may include business data and / or signaling data.

[0269] In this application, the terms "comprise" or "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process / method comprising a series of steps, or a system / product / apparatus comprising a series of units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes / methods / products / apparatus.

[0270] In the description of this application, unless otherwise specified, the number of nouns refers to "singular or plural," that is, "one or more." "At least one" means one or more. "Including at least one of the following: A, B, C" means that it may include A, or include B, or include C, or include A and B, or include A and C, or include B and C, or include A, B, and C. A, B, and C can be single or plural.

Claims

1. A communication method, characterized in that: include: At least two auxiliary synchronization signals and a physical broadcast channel block SSB are received from a network device, wherein the at least two auxiliary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two auxiliary SSBs corresponds to one of the at least two RISs.

2. The method according to claim 1, characterized in that Each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, and the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

3. The method according to claim 1 or 2, characterized in that: The method further comprises: Receive a primary SSB from the network device, wherein the primary SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

4. The method according to claim 3, characterized in that The first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

5. The method according to claim 3, characterized in that: The first configuration information includes partial configuration information of the SSs of the at least two secondary SSBs; A system information block SIB1 is received from the network device, wherein the SIB1 includes configuration information of all configuration information of the SSs of the at least two secondary SSBs except for the partial configuration information.

6. The method according to claim 5, characterized in that One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC, and block error rate BLER threshold.

7. The method according to any one of claims 3 to 6, characterized in that: The primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

8. The method according to claim 7, characterized in that The second configuration information includes one or more of the following: a sequence of a first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

9. The method according to any one of claims 3 to 8, characterized in that: The method further comprises: Detecting the main SSB to obtain a detection result of the main SSB, wherein the detection result of the main SSB includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; When the detection result is lower than a first threshold, it is determined to perform initial access on one of the at least two secondary SSBs.

10. The method according to claim 9, characterized in that The method further comprises: Detecting each secondary SSB to determine a detection result of each secondary SSB, wherein the detection result of each secondary SSB includes one or more of the following: sequence correlation, SNR, and received power; Determine the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; The first preamble is sent on the first RO.

11. A communication method, characterized in that: include: At least two secondary synchronization signals and a physical broadcast channel block SSB are sent to the terminal device, wherein the at least two secondary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponds to one of the at least two RISs. A RIS.

12. The method according to claim 11, characterized in that Each of the at least two secondary SSBs is sent at a corresponding time-frequency resource position, and the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

13. The method according to claim 11 or 12, characterized in that: The method further comprises: A main SSB is sent to the terminal device, wherein the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each secondary SSB.

14. The method according to claim 13, characterized in that The first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

15. The method according to claim 13, characterized in that The first configuration information includes partial configuration information of the SSs of the at least two secondary SSBs; A system message block SIB1 is sent to the terminal device, wherein the SIB1 includes configuration information of all configuration information of the SSs of the at least two secondary SSBs except the partial configuration information.

16. The method according to claim 15, characterized in that One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the one or more of the following items include: coding mode, adaptive modulation coding AMC or block error rate BLER threshold.

17. The method according to any one of claims 13 to 16, characterized in that: The primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

18. The method according to claim 17, characterized in that The second configuration information includes one or more of the following: a sequence of a first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

19. The method according to claim 17 or 18, characterized in that The method further comprises: A first preamble is received from the terminal device at the first RO.

20. The method according to any one of claims 13 to 19, characterized in that: After sending the main SSB to the terminal device, the method further includes: receiving a second preamble from the terminal device on a second RO corresponding to the primary SSB; Detecting the second preamble to obtain a detection result, wherein the detection result includes one or more of the following: sequence correlation, signal to interference plus noise ratio (SNR), and received power; If the detection result is lower than a second threshold, indication information is sent to the terminal device, where the indication information is used to instruct the terminal device to perform initial access through the assistance of the RIS.

21. A communication device, characterized in that: The device comprises a transceiver unit and a processing unit. The transceiver unit is used to receive at least two auxiliary synchronization signals and a physical broadcast channel block SSB from a network device, the at least two auxiliary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two auxiliary SSBs corresponds to one of the at least two RISs.

22. The device according to claim 21, characterized in that Each of the at least two secondary SSBs is received at a corresponding time-frequency resource position, and the time-frequency resource position is the indicated time frequency resource location or a predefined time-frequency resource location.

23. The device according to claim 21 or 22, characterized in that The transceiver unit is also used to receive a main SSB from the network device, and the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each auxiliary SSB.

24. The device according to claim 23, characterized in that The first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

25. The device according to claim 23, characterized in that The first configuration information includes partial configuration information of the SSs of the at least two secondary SSBs; The transceiver unit is further used to receive a system message block SIB1 from the network device, wherein the SIB1 includes configuration information of all configuration information of the SSs of the at least two secondary SSBs except for the partial configuration information.

26. The device according to claim 25, characterized in that One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the following item or items include: coding mode, adaptive modulation coding AMC, and block error rate BLER threshold.

27. The device according to any one of claims 23 to 26, characterized in that The primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

28. The device according to claim 27, characterized in that The second configuration information includes one or more of the following: a sequence of a first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

29. The device according to any one of claims 23 to 28, characterized in that The processing unit is further used to detect the main SSB to obtain a detection result of the main SSB, where the detection result of the main SSB includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; The processing unit is further configured to determine, when the detection result is lower than a first threshold, to perform initial access on one of the at least two secondary SSBs.

30. The device according to any one of claims 27 to 29, characterized in that The processing unit is further configured to detect each secondary SSB to determine a detection result of each secondary SSB, wherein the detection result of each secondary SSB includes one or more of the following: sequence correlation, SNR, and received power; The processing unit is further configured to determine the first RO and the first preamble code based on the second configuration information and the detection result of each secondary SSB; The processing unit sends the first preamble code on the first RO through the transceiver unit.

31. A communication device, characterized in that: The device comprises a transceiver unit and a processing unit. The transceiver unit is used to send at least two secondary synchronization signals and a physical broadcast channel block SSB to the terminal device, the at least two secondary SSBs are used for at least two smart metasurface RISs to assist in initial access, and each of the at least two secondary SSBs corresponds to one of the at least two RISs.

32. The device according to claim 31, characterized in that Each of the at least two secondary SSBs is sent at a corresponding time-frequency resource position, and the time-frequency resource position is an indicated time-frequency resource position or a predefined time-frequency resource position.

33. The device according to claim 31 or 32, characterized in that The transceiver unit is also used to send a main SSB to the terminal device, and the main SSB includes first configuration information, and the first configuration information is used to indicate the time-frequency resource position corresponding to each auxiliary SSB.

34. The device according to claim 33, characterized in that The first configuration information includes configuration information of the synchronization signal SS of each secondary SSB.

35. The device according to claim 33, characterized in that The first configuration information includes partial configuration information of the SSs of the at least two secondary SSBs; The transceiver unit is further used to send a system message block SIB1 to the terminal device, wherein the SIB1 includes configuration information of all configuration information of the SSs of the at least two secondary SSBs except for the partial configuration information.

36. The device according to claim 35, characterized in that One or more of the following items of the physical downlink shared channel PDSCH used to carry the SIB1 may be the same as the physical broadcast channel PBCH and / or the physical downlink control channel PDCCH, and the one or more of the following items include: coding mode, adaptive modulation coding AMC or block error rate BLER threshold.

37. The device according to any one of claims 33 to 36, characterized in that The primary SSB includes second configuration information, where the second configuration information is configuration information of the first random access channel opportunity RO corresponding to each secondary SSB.

38. The device according to claim 37, characterized in that The second configuration information includes one or more of the following: a sequence of a first preamble code corresponding to the first RO, a cyclic shift of the first preamble code corresponding to the first RO, and a time-frequency domain position corresponding to the first RO.

39. The device according to claim 37 or 38, characterized in that The transceiver unit is further configured to receive a first preamble code from the terminal device on the first RO.

40. The device according to any one of claims 33 to 39, characterized in that The transceiver unit is further configured to receive a second preamble from the terminal device on a second RO corresponding to the primary SSB; The processing unit is further configured to detect the second preamble code to obtain a detection result, wherein the detection result includes one or more of the following: sequence correlation, signal to interference plus noise ratio SNR, and received power; The processing unit is further configured to, when the detection result is lower than a second threshold, send indication information to the terminal device through the transceiver unit, wherein the indication information is configured to instruct the terminal device to perform initial access through the RIS assistance.

41. A communication device, characterized in that: The apparatus comprises at least one processor and a communication interface, wherein the at least one processor is configured to call a computer program or instruction stored in a memory to execute the method according to claims 1-10.

42. A communication device, characterized in that: The apparatus comprises at least one processor and a communication interface, wherein the at least one processor is configured to call a computer program or instruction stored in a memory to execute the method according to claims 11-20.

43. A communication system, characterized in that: The communication system comprises: an apparatus as claimed in claim 41 and an apparatus as claimed in claim 42.

44. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program or instruction, which, when executed on a processor, enables the method according to any one of claims 1 to 20 to be executed.

45. A computer program product, characterized in that The computer program product comprises a computer program or instructions, and when the computer program or instructions are run on a computer, the method according to any one of claims 1 to 20 is executed.

46. ​​A chip device, characterized in that: The chip device comprises at least one processor, and the at least one processor is used to execute computer programs or instructions to implement the method according to any one of claims 1-20.

Images