Signal transmission method and communication apparatus

Abstract

Provided in the embodiments of the present application are a signal transmission method and a communication apparatus, which can ensure, in a non-terrestrial network scenario, that terminals having different requirements can each determine a timing advance (TA). The method comprises: receiving, on at least one of a first resource and a second resource, a reference signal from a network apparatus, wherein the first resource is used for transmitting a first reference signal, the first reference signal is used for time and / or frequency synchronization, the second resource is used for transmitting a second reference signal, and the second reference signal is used for determining the location of a terminal; and on the basis of a TA, communicating with the network apparatus, wherein the TA is determined on the basis of the reference signal received on the at least one resource.

Description

Signal transmission method and communication device

[0001] The present application claims priority from the Chinese patent application No. 202411307138.6 filed on September 18, 2024, and entitled "Signal transmission method and communication device", the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the field of communication, in particular to a signal transmission method and a communication device. BACKGROUND

[0003] In the initial access process in the non-terrestrial network (NTN) scenario, due to the long distance and high speed of the satellite, the time offset and frequency offset are large, and in addition to searching for a synchronization signal for time-frequency synchronization, the user equipment (UE) side should also compensate for the time offset and frequency offset according to the own position and ephemeris information, and then determine the timing advance (TA), so as to initiate random access according to the TA.

[0004] However, in the initial access process, some UEs can obtain useful own position information through global navigation satellite system (GNSS) signals, and some UEs may not be able to obtain useful own position information. How to ensure that UEs with different needs can determine the TA is a problem to be solved at present. SUMMARY

[0005] The signal transmission method and the communication device provided by the embodiments of the present application can ensure that terminals with different needs can determine the timing advance (TA) in the non-terrestrial network (NTN) scenario.

[0006] To achieve the above-mentioned purpose, the embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, a signal transmission method is provided, which can be applied to a terminal side, for example, a terminal or a communication module in the terminal, or a circuit or chip (such as a modem chip, also known as a baseband chip, or a system on chip (SoC) chip or a system in package (SIP) chip containing a modem core) responsible for communication functions in the terminal. Taking the case where the method is applied to a terminal, the method comprises: receiving a reference signal from a network device on at least one of a first resource and a second resource, the first resource being used for transmitting a first reference signal, the first reference signal being used for time and / or frequency synchronization, and the second resource being used for transmitting a second reference signal, the second reference signal being used for determining a position of the terminal; and communicating with the network device according to a timing advance (TA), the TA being determined according to the reference signal received on the at least one resource.

[0008] In the embodiments of the present application, the terminal can receive a reference signal from a network device on at least one of a first resource and a second resource, the first resource being used for transmitting a first reference signal, the first reference signal being used for time and / or frequency synchronization, and the second resource being used for transmitting a second reference signal, the second reference signal being used for determining a position of the terminal. Then, the terminal can select whether to receive the second reference signal on the second resource according to its own needs for the position, so that terminals with different needs can all determine the TA.

[0009] In a second aspect, a signal transmission method is provided, which can be applied to a network side, for example, an access network device, a module (such as a circuit, a chip or a chip system, etc.) in the access network device, or a logic node, a logic module or software capable of realizing all or part of the functions of the access network device. Taking the case where the method is applied to a network device, the method comprises: transmitting a first reference signal on a first resource and a second reference signal on a second resource, the first reference signal being used for time and / or frequency synchronization, and the second reference signal being used for determining a position of a terminal, at least one of the first reference signal and the second reference signal being associated with a preconfigured resource; and communicating with the terminal according to the preconfigured resource.

[0010] In the embodiments of the present application, the network device transmits a first reference signal on a first resource and a second reference signal on a second resource, so that the terminal can receive a reference signal on at least one of the first resource and the second resource, and then the terminal can selectively receive the reference signal on at least one of the first resource and the second resource based on needs.

[0011] With reference to the first aspect or the second aspect, in a possible implementation, the second resource is determined according to the first resource reference position and an offset, and the first resource reference position is determined according to time domain resources and / or frequency domain resources occupied by the first reference signal. That is, the second resource is determined according to the time domain resources and / or the frequency domain resources occupied by the first reference signal, so that the terminal can not need to blindly detect the second reference signal, thereby reducing the complexity of receiving the second reference signal and saving power consumption.

[0012] With reference to the first aspect or the second aspect, in a possible implementation, the first resource reference position includes a first time domain resource reference position and / or a first frequency domain resource reference position, the first time domain resource reference position is determined according to time domain resources occupied by the first reference signal, and the first frequency domain resource reference position is determined according to frequency domain resources occupied by the first reference signal. That is, the first resource reference position can be a reference position in the time domain and / or a reference position in the frequency domain, thereby improving the flexibility of determining the second resource according to the first resource reference position. For example, the first time domain resource reference position can be a starting time position or an ending time position in the time domain resources occupied by the first reference signal. For example, the time domain resources occupied by the first reference signal are the i th frame or on the i th frame, and the starting time position can be a starting time position (also referred to as a starting boundary of the i th frame) of the i th frame or an ending boundary of the i th frame. In addition, considering that one first reference signal can occupy multiple time domain resources (for example, time domain resources with a granularity of a time slot or a symbol), the first time domain resource reference position can be determined according to any time domain resource in the multiple time domain resources. For example, the first time domain resource reference position can be a time position corresponding to any of the above time domain resources, such as a starting boundary, an ending boundary, or other time positions other than the starting boundary and the ending boundary. In other words, the first time domain resource reference position can be the k th symbol of the j th time slot.

[0013] With reference to the first aspect or the second aspect, in a possible implementation, the first frequency domain resource reference position is a center frequency or a frequency domain starting position of the first reference signal. It can be understood that the center frequency position or the frequency domain starting position of the frequency domain resources occupied by the first reference signal can be understood as the center frequency or the frequency domain starting position of the first reference signal. In addition, the center frequency of the first reference signal can also be replaced by GSCN or other frequency units (such as the center frequency of a subcarrier) that can represent the center frequency of the first reference signal. That is, the first frequency domain resource reference position can be determined according to the frequency domain resources occupied by the first reference signal, thereby improving the flexibility of determining the first frequency domain resource reference position.

[0014] In a possible implementation manner of the first aspect or the second aspect, the offset includes a time offset and / or a frequency offset compared with the first resource reference position, the time offset is used to determine a time domain resource occupied by the second reference signal, and the frequency offset is used to determine a frequency domain resource occupied by the second reference signal. That is, the time interval between the time domain resource occupied by the second reference signal and the first resource reference position, and / or the frequency interval between the frequency domain resource occupied by the second reference signal and the first resource reference position can be determined by the offset, and then the time domain resource and / or the frequency domain resource occupied by the second reference signal can be determined, so that the second resource used to transmit the second reference signal is obtained. In addition, since the second resource is the time domain resource and / or the frequency domain resource occupied by the second reference signal, rather than the candidate resource (for example, the synchronization raster) obtained by sweeping, the terminal can not receive the second reference signal by sweeping, so that the complexity, power consumption and latency overhead of the terminal receiving the second reference signal can be reduced.

[0015] In a possible implementation manner of the first aspect or the second aspect, the time offset can be used to determine a starting time position or an ending time position of the time domain resource occupied by the second reference signal. That is, the terminal or the network device can determine the time domain resource occupied by the second reference signal according to the first time domain resource reference position and the time offset, so that the flexibility of determining the time domain resource occupied by the second reference signal is improved. For example, the first time domain resource reference position can be a starting time position of the time domain resource occupied by the first reference signal, and then the starting time position of the time domain resource occupied by the second reference signal is the sum of the starting time position of the time domain resource occupied by the first reference signal and the time offset. In addition, the time length (for example, the number of occupied symbols, or the number of occupied time slots, etc.) corresponding to the time domain resource occupied by the second reference signal can be the time length corresponding to the time domain resource occupied by the first reference signal, or other length.

[0016] In a possible implementation manner of the first aspect or the second aspect, the frequency offset is used to determine a center frequency or a frequency domain starting position of the frequency domain resource occupied by the second reference signal. That is, the terminal or the network device can determine the frequency domain resource occupied by the second reference signal according to the first frequency domain resource reference position and the frequency offset, so that the flexibility of determining the frequency domain resource occupied by the second reference signal is improved. For example, the first frequency domain resource reference position can be a center frequency of the frequency domain resource occupied by the first reference signal, and then the center frequency of the frequency domain resource occupied by the second reference signal is the sum of the center frequency of the frequency domain resource occupied by the first reference signal and the frequency offset. In addition, the bandwidth (for example, the number of occupied subcarriers) corresponding to the frequency domain resource occupied by the second reference signal can be the bandwidth corresponding to the frequency domain resource occupied by the first reference signal, or other bandwidth.

[0017] In a possible implementation of the first aspect or the second aspect, the time offset is information of any one of the following granularities: a symbol, a slot, a subframe, or a frame, and the frequency offset is information of any one of the following granularities: a subcarrier, a carrier, a resource block (RB), or a global synchronization channel number (GSCN). That is, the time offset and / or the frequency offset can reuse the resource granularity defined in the existing protocol, and the implementation complexity can be reduced.

[0018] In a possible implementation of the first aspect or the second aspect, the offset is indicated by the first reference signal. That is, the offset can be indicated by the first reference signal, so that the terminal can determine the second resource for receiving the second reference signal according to the offset and the time domain and / or frequency domain resource occupied by the first reference signal, and the modification on the terminal side can be reduced.

[0019] In a possible implementation of the first aspect or the second aspect, the second resource is determined according to M candidate frequency points, where M is an integer greater than 1. For example, the terminal can determine the second resource according to the M candidate frequency points. The network device can select at least one frequency point from the M candidate frequency points included in the second resource to send the second reference signal. That is, the second resource is a candidate resource, and the terminal can receive the second reference signal in a frequency sweeping manner according to the second resource, so as to select one resource from the first resource and the second resource to receive the reference signal, to perform time-frequency synchronization and determine the TA, thereby reducing the time delay and power consumption of the terminal when sending data to the network.

[0020] In addition, the frequency corresponding to each of the M candidate frequency points can be the center frequency or the frequency domain starting position of the second reference signal.

[0021] In a possible implementation of the first aspect or the second aspect, the M candidate frequency points are determined according to a reference candidate frequency point and a frequency interval, where the frequency interval is used to indicate the frequency difference between any two of the M candidate frequency points. That is, the terminal and the network device can determine the M candidate frequency points according to the reference candidate frequency point and the frequency interval, and the implementation complexity of determining the second resource can be reduced.

[0022] In a possible implementation of the first aspect or the second aspect, the frequency difference between any two of the M candidate frequency points is information of any one of the following granularities: a subcarrier, a carrier, a resource block (RB), or a global synchronization channel number (GSCN). That is, the frequency difference between any two of the M candidate frequency points can reuse the frequency domain resource granularity defined in the existing protocol, and the implementation complexity can be reduced.

[0023] In a possible implementation manner of the first aspect or the second aspect, the reference candidate frequency point comprises a candidate frequency point with the minimum frequency among the M candidate frequency points, and / or a candidate frequency point with the maximum frequency. That is, the reference frequency point can be a candidate frequency point with the minimum frequency among the M candidate frequency points, and / or a candidate frequency point with the maximum frequency, thereby increasing flexibility of determining the M candidate frequency points. For example, for the reference candidate frequency point being a candidate frequency point with the minimum frequency among the M candidate frequency points, the terminal can sequentially determine the remaining M-1 candidate frequency points according to the frequency interval. Similarly, for the reference candidate frequency point being a candidate frequency point with the maximum frequency among the M candidate frequency points, the terminal can also sequentially determine the remaining M-1 candidate frequency points according to the frequency interval.

[0024] In a possible implementation manner of the first aspect or the second aspect, the first resource is determined according to N candidate frequency points, and any candidate frequency point in the N candidate frequency points is adjacent to any candidate frequency point in the M candidate frequency points. That is, since the N candidate frequency points and the M candidate frequency points are staggered in the frequency domain, the terminal can sequentially search for the first reference signal and the second reference signal according to the frequency size, thereby reducing complexity and power consumption of searching for the reference signal.

[0025] In a possible implementation manner of the first aspect or the second aspect, the system information associated between the first reference signal and the second reference signal is the same. That is, since the system information associated between the first reference signal and the second reference signal is the same, the terminal can select one of the first resource and the second resource to receive the reference signal for time-frequency synchronization and determining TA, thereby reducing latency and power consumption of the terminal sending data to the network.

[0026] In a possible implementation manner of the first aspect or the second aspect, the second reference signal is further used for time and / or frequency synchronization. That is, the second reference signal is further used for time and / or frequency synchronization, which can enable the terminal to receive one of the first reference signal and the second reference signal, and can communicate with the network device according to the preconfigured resource.

[0027] In a third aspect, a communication apparatus is provided for implementing the above methods. The communication apparatus can be the terminal or the network device in any of the above aspects or any of the implementation manners thereof, or a device containing the terminal or the network device, or a device contained in the terminal or the network device, such as a chip. The communication apparatus comprises modules, units, or means for implementing the above methods, which can be implemented by hardware, software, or by hardware executing corresponding software. The hardware or software comprises one or more modules or units corresponding to the above functions.

[0028] In some possible design, the communication apparatus can include a processing module and a transceiver module. The transceiver module, which can also be referred to as a transceiver unit, is configured to implement the functions of transmitting and / or receiving in any of the above aspects and any possible implementation thereof. The transceiver module can be composed of a transceiver circuit, a transceiver, a transceiver, or a communication interface. The processing module can be configured to implement the processing functions in any of the above aspects and any possible implementation thereof.

[0029] In some possible design, the transceiver module includes a transmitting module and a receiving module, which are configured to implement the functions of transmitting and receiving in any of the above aspects and any possible implementation thereof.

[0030] In a fourth aspect, a communication apparatus is provided, which includes at least one processor, and the processor is configured to execute computer programs or instructions to enable the communication apparatus to perform the method in any of the above aspects.

[0031] In a possible implementation, the communication apparatus further includes the memory. Optionally, the memory is coupled to the processor, and the memory can be integrated with the processor, or the memory can be independent of the processor. Optionally, the processor is configured to execute the computer programs or instructions stored in the memory.

[0032] In a possible implementation, the memory is independent of the communication apparatus.

[0033] In a possible implementation, the communication apparatus further includes a communication interface, which is configured to communicate with modules outside the communication apparatus.

[0034] The communication apparatus can be a terminal or a network apparatus in any of the above aspects or any possible implementation thereof, or an apparatus including the terminal or the network apparatus, or an apparatus included in the terminal or the network apparatus, such as a chip.

[0035] In a fifth aspect, a computer readable storage medium is provided, which stores computer programs or instructions, and when the computer programs or instructions are executed on a communication apparatus, the communication apparatus can perform the method in any of the above aspects or any possible implementation thereof.

[0036] In a sixth aspect, a computer program product is provided, which includes instructions, and when the instructions are executed on a communication apparatus, the communication apparatus can perform the method in any of the above aspects or any possible implementation thereof.

[0037] In a seventh aspect, a communication apparatus (for example, the communication apparatus can be a chip or a chip system) is provided, which includes a processor, and the processor is configured to implement the functions in any of the above aspects or any possible implementation thereof.

[0038] In some possible design, the communication apparatus includes a memory configured to store necessary program instructions and data.

[0039] In some possible design, the apparatus is a chip system, which can be composed of a chip or include a chip and other discrete devices.

[0040] It can be understood that, when the communication apparatus in any of the third aspect to the seventh aspect is a chip, the sending action / functionality can be understood as output, and the receiving action / functionality can be understood as input.

[0041] The technical effects brought by the design in any of the third aspect to the seventh aspect can refer to the technical effects brought by the design in the first aspect or the second aspect, which will not be repeated here.

[0042] In an eighth aspect, a communication system is provided, which includes the terminal and the network apparatus in any of the above aspects and any implementation manner thereof. BRIEF DESCRIPTION OF DRAWINGS

[0043] FIG. 1 is a schematic diagram of a network architecture of an NTN according to an embodiment of the present application;

[0044] FIG. 2 is a schematic diagram of a CU and DU separation architecture according to an embodiment of the present application;

[0045] FIGS. 3-5 are schematic diagrams of RAN architectures based on an NTN according to embodiments of the present application;

[0046] FIG. 6 is a schematic diagram of a comparison between time alignment based on TA and time alignment not based on TA according to an embodiment of the present application;

[0047] FIG. 7 is a schematic diagram of a process of terminal initial access according to an embodiment of the present application;

[0048] FIG. 8 is a schematic diagram of a relationship between a synchronization raster and a center frequency of an SSB according to an embodiment of the present application;

[0049] FIG. 9 is a schematic diagram of time-frequency resources occupied by an SSB in a single time slot according to an embodiment of the present application;

[0050] FIG. 10 is a schematic diagram of a process of a signal transmission method according to an embodiment of the present application;

[0051] FIG. 11 is a schematic diagram of indicating a second resource according to a frequency offset according to an embodiment of the present application;

[0052] FIG. 12 is a schematic diagram of time domain distribution between time domain resources occupied by a first reference signal and time domain resources occupied by a second reference signal according to an embodiment of the present application;

[0053] FIG. 13 is a schematic diagram of an association relationship between a first reference signal and SIB1 according to an embodiment of the present application;

[0054] FIGS. 14-15 are schematic diagrams of frequency domain distribution between N candidate frequencies and M candidate frequencies according to an embodiment of the present application;

[0055] FIGS. 16-17 are schematic diagrams of a structure of a communication apparatus according to an embodiment of the present application. DETAILED DESCRIPTION

[0056] For the convenience of understanding the technical solutions provided by the embodiments of the present application, first, a brief introduction of the system applicable to the present application and related technical terms is given.

[0057] In order to facilitate the understanding of the embodiments of the present application, the following points are explained before the embodiments of the present application are introduced.

[0058] 1. In the embodiments of the present application, for the convenience of description, when referring to numbers or indexes, the numbers can be consecutively numbered from 1, or consecutively numbered from 0, or numbered from any parameter, and no specific limitation is made to this.

[0059] 2. The terms “predefined”, “previously defined”, “preconfigured (or previously configured)”, and “protocol agreement” can be mutually replaced, and the predefinition can be realized by pre-storing corresponding codes, tables or other means for indicating related information in a device (for example, a terminal or a network apparatus), and the embodiments of the present application do not limit the specific implementation manner. Wherein, “storing” can mean storing in one or more memories.

[0060] 3. The “protocol” referred to in the embodiments of the present application can refer to a standard protocol in the field of communication, which can include long term evolution (LTE) protocol, new radio (NR) protocol, wireless fidelity (Wi-Fi), and related protocols applied in future communication systems, and the embodiments of the present application do not limit this.

[0061] 4、In the embodiments of the present application, the descriptions such as "when", "in the case of", "if" and "whether" all refer to that under certain objective condition, the device (for example, terminal or network device) will make corresponding processing, which is not limited to time, and does not require the device to have a judgment action when implemented, nor means that there is other limitation. In addition, the description of the above conditions can be understood as a necessary condition, and whether the condition is a sufficient condition or a sufficient and necessary condition is not limited. For example, "in the case of A, performing B" can be understood as "in the case of at least satisfying A, performing B".

[0062] 5、In the embodiments of the present application, "sending information" can be understood as that one device (or apparatus) sends information to another device (or apparatus), or can also be understood as that one logical module in the device sends information to another logical module. For example, "the network device sends information" can be understood as that the network device sends information to another device (such as a terminal), or can be understood as that the logical module 1 in the network device sends information to the logical module 2 in the network device.

[0063] In addition, "receiving information" in the embodiments of the present application can be understood as that one device (or apparatus) receives information from another device (or apparatus), or can also be understood as that one logical module in the device receives information from another logical module. For example, "the terminal receives information" can be understood as that the terminal receives information from another device (such as a network device), or can be understood as that the logical module 1 in the terminal receives information from the logical module 2 in the terminal.

[0064] In addition, "sending information to (terminal)" can be understood as that the destination of the information is the terminal, which can include directly or indirectly sending information to the terminal. "Receiving information from (network device)" or "receiving information from (network device)" can be understood as that the source of the information is the network device, which can include directly or indirectly receiving information from the network device. The information between the source and the destination of the information sending can be processed as necessary, for example, format change, etc., but the destination can understand the valid information from the source. Similar expressions in the present application can be understood similarly, which will not be repeated here.

[0065] 6、In the description of the embodiments of the present application, unless otherwise specified, "and / or" in the embodiments of the present application represents three possible relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. And "at least one of the following" or the like means any combination of the items, including any combination of single or multiple items. In addition, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, "first", "second", etc. are used to distinguish the same items or similar items with basically the same function and role. Those skilled in the art can understand that "first", "second", etc. do not limit the quantity and execution order, and "first", "second", etc. also do not necessarily mean different. At the same time, in the embodiments of the present application, "exemplary" or "for example" means as an example, illustration or description.

[0066] In order to facilitate understanding of the technical solutions provided by the embodiments of the present application, first, a brief introduction of related technologies of the present application is given. The brief introduction is as follows:

[0067] First, non-terrestrial networks (NTN):

[0068] Since the traditional terrestrial network (TN), such as NR system (also can be called as 5th generation (5G) system), or internet of thing (IoT) etc., cannot provide seamless coverage for terminals (for example, in the scene of communication in the physical area where base station cannot be deployed, such as sea, desert, air, etc.), therefore, NR system, IoT system, and future communication system etc. can introduce NTN to provide seamless coverage service for terminals.

[0069] NTN can deploy part or all functions of base station on non-ground network equipment (such as ship, high-altitude platform, unmanned aerial vehicle or satellite) to provide communication coverage for terminals to improve the reliability of communication system. It should be noted that for the sake of understanding, in the following, the NTN-radio access network (RAN) equipment is taken as a satellite for example to be described, which should not be understood as that the NTN-RAN equipment in the present application is limited to satellite only, which is uniformly described here, and the following will not be repeated.

[0070] Fig. 1 is a network architecture schematic diagram of an NTN provided by an embodiment of the present application, which can include a terminal, a radio access network (AN), and a core network (CN), which are introduced as follows.

[0071] 1.1. Terminal:

[0072] In a possible implementation, the terminal can be a device for implementing a wireless communication function, such as a terminal or a chip that can be used in a terminal, and the like. The terminal can be a user equipment (UE), an access terminal, a terminal unit, a terminal station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a terminal agent, or a terminal device, and the like in a 5G network or a future evolved public land mobile network (PLMN). The access terminal can be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device, or other processing devices connected to a wireless modem, a vehicle-mounted device, a wearable device, a VR terminal, an AR terminal, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, and the like. In a possible implementation, the terminal can be mobile or fixed.

[0073] 1.2. AN:

[0074] The AN exists between the terminal and the CN, and provides a communication connection therebetween. The AN can also be referred to as a RAN, which is an entity for transmitting a signal, or receiving a signal, or transmitting and receiving a signal.

[0075] In a possible implementation, the RAN device can also be referred to as an access node, a RAN entity, a RAN node, or a device with base station processing functions, and the like. For example, the RAN device can include a non-terrestrial network device (or NTN-RAN device) and a terrestrial RAN device. The NTN-RAN device can be a device that provides coverage for a terminal by deploying a base station or part of the base station function on a non-terrestrial device (such as a satellite, a high-altitude platform, or a drone, and the like). The terrestrial RAN device can include a base station (such as a next-generation node B (gNodeB, gNB)) in an NR system, or one or a group (including multiple antenna panels) of antenna panels of a base station in 5G, or can also be a network node that constitutes a gNB, a transmission and reception point (TRP or transmission point, TP), or a transmission measurement function (TMF), such as a building base band unit (BBU), or a centralized unit (CU) or a distributed unit (DU), an RSU with base station functions, or a wired access gateway, or a CN network element of 5G. Alternatively, the TN-RAN device can also include an access point (AP) in a Wi-Fi system, a wireless relay node, a wireless backhaul node, various forms of macro base stations, micro base stations (also referred to as small stations), relay stations, access points, wearable devices, vehicle-mounted devices, and the like. Alternatively, the RAN device can also include an access network device or a base station in a future mobile communication system.

[0076] It can be understood that in a future mobile communication system, the RAN device can also have other naming manners, which are all included in the protection scope of the embodiments of the present application, and the present application does not make any limitation thereto.

[0077] In a possible implementation, the RAN device can include a CU, a DU, a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The RAN device can also include an active antenna unit (AAU). The CU implements part of the function of the network device, and the DU implements part of the function of the network device. For example, the CU is responsible for processing non-real-time protocols and services, and implements the functions of the radio resource control (RRC) layer and / or the packet data convergence protocol (PDCP) layer. The DU is responsible for processing the physical layer protocol and real-time services, and implements the functions of the radio link control (RLC) layer, the media access control (MAC) layer, and the physical (PHY) layer. The AAU implements part of the physical layer processing function, the radio frequency processing, and the related functions of the active antenna. Since the information of the RRC layer eventually becomes the information of the PHY layer, or is converted from the information of the PHY layer, in this architecture, high-layer signaling, such as RRC signaling, can also be considered as being sent by the DU, or being sent by the DU and the AAU. It can be understood that the RAN device can be a device including one or more of the CU node, the DU node, and the AAU node. In addition, the CU can be divided into a network device in the RAN or a network device in the CN, and the embodiments of the present application do not limit the CU.

[0078] In addition, the CU can also be divided into a control plane (CU-CP) and a user plane (CU-UP), which are exemplarily described below.

[0079] FIG. 2 is a schematic diagram of a CU and DU separation architecture provided by an embodiment of the present application. As shown in FIG. 2, the CU-CP is responsible for the control plane function, mainly including the RRC and the PDCP corresponding to the control plane (i.e., PDCP-C). The PDCP-C is mainly responsible for the encryption and decryption of the control plane data, integrity protection, data transmission, etc. The CU-UP is responsible for the user plane function, mainly including the service data adaptation protocol (SDAP) layer and the PDCP corresponding to the user plane (i.e., PDCP-U). The SDAP is mainly responsible for processing the data of the core network and mapping the flow to the bearer. The PDCP-U is mainly responsible for the encryption and decryption of the data plane, integrity protection, header compression, sequence number maintenance, data transmission, etc. The CU-CP and the CU-UP are connected through the E1 interface. The CU-CP is connected to the core network through the NG interface by the RAN device. The control plane (i.e., F1-C) of the CU is connected to the DU through the F1 interface. The user plane (i.e., F1-U) of the CU is connected to the DU through the F1 interface. Of course, there is also a possible implementation that the PDCP-C is also in the CU-UP.

[0080] It should be understood that the CU (or CU-CP and CU-UP), DU or RU can also have different names in different systems, but those skilled in the art can understand their meanings. For example, in an open radio access network (O-RAN or ORAN) system, the CU can also be referred to as an open CU (O-CU), the DU can also be referred to as an open DU (O-DU), the CU-CP can also be referred to as an open CU-CP (O-CU-CP), the CU-UP can also be referred to as an open CU-UP (O-CU-UP), and the RU can also be referred to as an open RU (O-RU). For the convenience of description, the CU, CU-CP, CU-UP, DU and RU are taken as examples for description in the embodiments of the present application. Any one of the CU (or CU-CP, CU-UP), DU and RU in the embodiments of the present application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0081] In addition, in the ORAN system, the RAN node communicates through a backhaul CN and communicates with the terminal through an air interface. The ORAN system also includes a RAN intelligent controller (RIC), which can specifically include a non-real time RAN intelligent controller (Non-RT RIC) and a near-real time RAN intelligent controller (Near-RT RIC). The Non-RT RIC is used to implement non-real-time intelligent management of RAN functions, and the Non-RT RIC is located in a service management and orchestration framework (SMO) module. The Near-RT RIC is used to implement near-real-time intelligent management of the RAN, and implements near-real-time control and optimization of modules and resources of the O-RAN through data collection and related operations on the E2 interface.

[0082] 1.3, CN:

[0083] The CN is mainly responsible for maintaining subscription data of the mobile network, and provides functions such as session management, mobility management, policy management, and security authentication for the terminal. For details, refer to the related protocols of 3GPP, which will not be described herein.

[0084] For example, the NTN can be classified according to the working mode of the satellite, such as a transparent mode architecture and a regenerative mode architecture. In the transparent mode architecture, the satellite functions to perform radio frequency filtering, frequency conversion, and amplification. That is, in the transparent satellite architecture, the satellite mainly functions as a layer 1 (L1) relay device for regenerating the physical layer signal (i.e., radio frequency filtering, frequency conversion, and amplification processing), without other higher protocol layers. The regenerative mode can refer to the satellite functioning as a base station with partial or full data processing capability of the base station.

[0085] The following describes several examples of RAN architectures based on NTNs in conjunction with the accompanying drawings.

[0086] FIG. 3 is a schematic diagram of an NTN-based NG-RAN architecture according to an embodiment of the present application. As shown in FIG. 3, the RAN architecture (or next-generation RAN (NG-RAN)) is an architecture with transparent satellite, including a remote radio unit (RRU) and a base station. The RRU can include a satellite and an NTN gateway. The satellite can operate in a transparent mode, i.e., the satellite acts as a layer 1 relay between the terminal and the base station. For example, the satellite is used to regenerate the PHY layer signal, i.e., the satellite can not have high-layer protocol layer (e.g., RRC layer) functions. It can be understood that the transmission link between the satellite and the terminal can be referred to as a service link (SL). The transmission link between the satellite and the NTN gateway can be referred to as a feeder link (FL). The NTN gateway can be deployed together with the base station or separately, which is not limited in the present application.

[0087] In addition, different satellites can be connected to the same ground base station.

[0088] It should be understood that for the feeder link, the FL can include the transmission link between the satellite and the NTN gateway, and the transmission link between the NTN gateway and the base station, in the case that the NTN gateway and the base station are deployed separately.

[0089] As shown in FIG. 3, the terminal can access the base station through the satellite, and then access the core network (CN) (e.g., a 5th generation core network (5G CN)) through the base station.

[0090] It can be understood that in FIG. 3, the satellite only plays a role of frequency conversion and forwarding, i.e., it is equivalent to an analog radio frequency relay. That is, the satellite copies the NR-Uu wireless interface signal from the feeder link to the service link, and vice versa. The satellite wireless interface transmission on the feeder link is the NR-Uu interface signal, i.e., the satellite does not terminate the NR-Uu interface signal, but copies the signal. In addition, the NTN gateway supports all necessary functions for forwarding all NR-Uu interface signals.

[0091] FIG. 4 is another NTN-based RAN architecture provided by the embodiments of the present application. As shown in FIG. 4, the RAN architecture is a regenerative satellite architecture without inter-satellite link (ISL), and the difference between the architecture shown in FIG. 4 and the transparent satellite architecture shown in FIG. 3 is that the satellite in FIG. 4 has the capability of a base station, and the satellite can serve as a RAN device to provide services for terminals. The ISL can refer to a transmission link between satellites. The ISL can be a wireless interface or an optical interface, and the specific ISL can be defined by 3GPP, for example, using an Xn interface, which is not limited specifically.

[0092] In addition, the interface between the satellite and the NTN gateway can be a satellite radio interface (SRI).

[0093] FIG. 5 is another NTN-based RAN architecture provided by the embodiments of the present application. As shown in (a) of FIG. 5, the RAN architecture is a regenerative satellite architecture with ISL, and the difference between the architecture shown in (a) of FIG. 5 and the architecture shown in FIG. 4 is that the architecture shown in (a) of FIG. 5 has ISL, that is, the satellite #1 and the satellite #2 can transmit through the ISL.

[0094] As shown in (b) of FIG. 5, the difference between the RAN architecture shown in (b) of FIG. 5 and the transparent satellite architecture shown in FIG. 3 is that the satellite shown in (b) of FIG. 5 has part of the processing function of a base station, for example, the DU function of a RAN device, and the satellite can serve as a DU of a RAN device, and the base station can serve as a CU of a RAN device.

[0095] It can be understood that in the architectures shown in FIGS. 4-5, the base station function or the DU is deployed on the satellite. In this architecture, the satellite acts as a base station to realize the regeneration of the received signal from the ground, that is, to transmit the NR-Uu interface signal on the service link between the terminal and the satellite, and to transmit the SRI signal on the feeder link between the NTN gateway and the satellite.

[0096] In addition, the above is introduced by taking the satellite as an example, and the satellite can be replaced by other non-ground network devices, for example, a ship, a high-altitude platform, or a drone, etc., which is not limited specifically in the embodiments of the present application.

[0097] It should be understood that the characteristic of the NTN scenario is large transmission delay, and therefore the timing advance (TA) in the NTN scenario is different from that of the ground communication. In order to better understand the present application, the TA is introduced as follows.

[0098] Second, TA:

[0099] An important feature of uplink transmission is that different terminals are orthogonal in time and frequency domain, i.e., the uplink transmissions from different terminals in the same cell do not interfere with each other. In order to ensure the orthogonality of uplink transmission to avoid intra-cell interference, the base station expects that the time of arrival of signals from different terminals in the same subframe at the base station is substantially aligned.

[0100] It can be understood that the TA can refer to the round trip time (RTT) of transmission between the terminal and the base station, and then relative to the time domain position of the scheduled uplink transmission (i.e., the time at which the base station expects to receive the signal of the uplink transmission, which can be a time domain resource such as a frame, a subframe, a time slot, or a symbol), the terminal can transmit in advance TA / 2, and after the transmission delay, the time at which the signal sent by the terminal actually arrives at the base station is the time at which the base station expects to receive the signal. In fact, at the terminal side, the TA can refer to the negative offset between the time at which the terminal receives the start time of the downlink subframe from the base station and the time at which the terminal sends the start time of the uplink subframe corresponding to the downlink subframe, and the specific value of the negative offset is the RTT. In addition, the uplink subframe corresponding to the downlink subframe here refers to the timing at which the uplink subframe actually arrives at the base station after the transmission delay being the same as the timing at which the base station sends the downlink subframe.

[0101] In order to facilitate understanding, the TA is described below in conjunction with FIG. 6.

[0102] FIG. 6 is a comparison diagram provided by an embodiment of the present application for time alignment based on TA and not for time alignment. As shown in (a) of FIG. 6, because the transmission delays between different terminals are different, the timings (or occasions) at which the uplink symbols of different terminals arrive at the base station side are different, and if timing advance is not performed, timing deviation will occur at the base station side, which will cause uplink transmission interference. For example, in (a) of FIG. 6, the uplink subframe with a one-way transmission delay of TP1 and the uplink subframe with a one-way transmission delay of TP2 (TP2 is greater than TP1) have a timing deviation of 2×(TP2-TP1) at the base station side, i.e., the uplink subframe corresponding to TP1 and the uplink subframe corresponding to TP2 will interfere with each other.

[0103] As shown in (b) of FIG. 6, the terminal performs timing advance, and then the timings of uplink symbols with different delays that arrive at the base station side are aligned, so that there is no timing deviation. For example, in (b) of FIG. 6, the uplink subframe with a one-way transmission delay of TP1 is sent in advance by a time length of TP1, and the uplink subframe with a one-way transmission delay of TP2 is sent in advance by a time length of TP2, and then the two uplink subframes actually arrive at the base station side at corresponding times, and there is no timing deviation, which can ensure the orthogonality of uplink transmission.

[0104] It can be understood that, as shown in (b) of FIG. 6, TA is equal to 2TP1 or 2TP2, that is, the offset between the starting time of the uplink symbol and the starting time of the downlink symbol, and the terminal sends the uplink subframe in advance by TA / 2 in advance relative to the timing of the downlink subframe.

[0105] It should be understood that the transmission delay in the NTN scenario is greater than that of ground communication, and due to the high-speed movement of the satellite, the frequency offset is also large, so the terminal needs to calculate the time offset and frequency offset based on its own position and the satellite position in addition to the time and frequency synchronization based on the synchronization signal, and compensate for the time offset and frequency offset to determine TA. Wherein, the terminal can obtain its own position by receiving global navigation satellite system (GNSS) signals, and the satellite position is determined based on the ephemeris information sent by the network side, which can be carried by the system information block (SIB).

[0106] For ease of understanding, the terminal determines TA and initiates random access according to TA, which is described below in conjunction with FIG. 7.

[0107] FIG. 7 is a flowchart of a terminal initial access according to an embodiment of the present application. As shown in FIG. 7, the flow includes:

[0108] S701, the RAN device sends a synchronization signal / physical broadcast channel block (SSB) to the terminal. Accordingly, the terminal receives the SSB from the RAN device.

[0109] The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). The PSS and / or SSS are used for downlink time synchronization and downlink frequency synchronization, and the terminal can obtain downlink time synchronization and downlink frequency synchronization through the PSS and / or SSS, thereby completing timing estimation and obtaining a physical cell identifier (PCID), and then decoding the PBCH.

[0110] The PBCH includes a master information block (MIB), and the MIB includes configuration parameters required for acquiring remaining minimum system information (RMSI). The RMSI, also referred to as a system information block (SIB) 1, includes system information (SI) required for the terminal to complete initial access, such as random access (RA) resources, which can include time-frequency resources (including time-domain resources and frequency-domain resources) for transmitting a preamble.

[0111] In addition, the SIB 1 can further include scheduling information for acquiring other SIBs, which is used to indicate time-frequency resources for receiving the other SIBs. For example, the SIB 1 can include time-frequency resources for acquiring a SIB 19. The SIB 19 includes NTN configuration parameters, which can include ephemeris information of a satellite, through which the terminal can determine a satellite position in order to determine a TA.

[0112] It should be understood that the terminal receives the SSB by searching for the SSB in a sweeping manner, and the 3rd generation partnership project (3GPP) protocol defines a manner in which the terminal searches for the SSB and a pattern in which the RAN device transmits the SSB.

[0113] For example, the terminal can search for the SSB according to a synchronization raster. The synchronization raster includes a plurality of candidate frequencies, and a frequency corresponding to the candidate frequencies is referred to as a synchronization signal reference frequency (SSREF), which corresponds to a center frequency of the SSB. In other words, the above-mentioned candidate frequencies indicate possible positions of the SSB in the frequency domain.

[0114] In addition, the above-mentioned candidate frequencies can be represented by a global synchronization channel number (GSCN). For example, Table 1 shows a correspondence between the SSREF and the GSCN in different frequency ranges.

[0115] Table 1

[0116] As shown in Table 1, the interval between each SSREF in the synchronization raster is the same, which can also be expressed as the step size of the terminal searching the candidate frequency point of the SSB. In addition, the step size is different for different FR, for example, in 0-3000MHz, the step size is 1200kHz; in 3000-24250MHz, the step size is 1.44MHz; in 24250-100000MHz, the step size is 17.28MHz.

[0117] FIG. 8 is a schematic diagram of the relationship between a synchronization raster and the center frequency of an SSB according to an embodiment of the present application. As shown in FIG. 8, it is assumed that the synchronization raster includes 5 candidate frequency points, which correspond to 5 SSREFs respectively, and the 5 SSREFs are sorted in ascending order of frequency as SSREF#1-#5. In addition, the center frequency of the SSB that can occur is the above-mentioned SSREF#1-#5. For example, the SSB can occur at the frequency domain position corresponding to SSREF#2, that is, the center frequency of the SSB is SSREF#2.

[0118] In addition, FIG. 8 is only an example, for example, the above-mentioned SSREF can also be expressed by GSCN, which is not limited in the embodiments of the present application.

[0119] It should be understood that the terminal can search the SSB for each candidate frequency point in a sweeping manner, for example, it can search in ascending order of the frequency corresponding to the frequency point, or other order, which is not limited.

[0120] It can be understood that the 3GPP protocol divides different FRs into different operation bands, and different operation bands can correspond to different radio frequency indicators. In addition, the operation band can define different subcarrier spacings (SCS), synchronization rasters, and SSB patterns. For example, in FR1 (410-7125MHz), the operation bands for satellites are n255 and n256 respectively. The uplink operating frequency range corresponding to n255 is 1980-2020MHz, and the downlink operating frequency range is 2170-2200MHz. The uplink operating frequency range corresponding to n256 is 1626.5-1660.5MHz, and the downlink operating frequency range is 1525-1559MHz, and the working mode is FDD mode.

[0121] In addition, the pattern of the SSB refers to a pattern of time-frequency resources occupied by the SSB transmitted by the network side. It can be understood that the network side can transmit the SSB in a manner of beam sweeping, and the transmission of the SSB in the manner of beam sweeping can refer to that the SSB is transmitted by using beams with different directions at different times to cover the entire cell. The beam for transmitting the SSB can be referred to as an SSB beam, and different SSB beams have different directions, that is, different SSB beam coverage ranges. A plurality of SSBs transmitted to complete one beam sweeping form an SSB burst set, and the maximum number of SSBs included in one SSB burst set can be 4, 8, 16, or 64. The transmission of the SSB burst set needs to be completed within 5 ms of a half frame, and the transmission period of the SSB burst set can be {5, 10, 20, 40, 80, 160} ms.

[0122] For example, when the SCS is 30 kHz, the SSB burst set can be cyclic in a time slot, that is, in each time slot, the indexes of the plurality of symbols occupied by the SSB in each time slot are the same, which will be described below in conjunction with FIG. 9.

[0123] FIG. 9 is a schematic diagram of time-frequency resources occupied by SSBs in a single time slot according to an embodiment of the present application. As shown in (a) of FIG. 9, it is assumed that a time slot includes symbols #0 to #13, and two SSBs (namely, SSB #1 and SSB #2) can be transmitted in a time slot. SSB #1 occupies four symbols (namely, symbols #2 to #5), and SSB #2 occupies symbols #8 to #11.

[0124] As shown in (b) of FIG. 9, in the frequency domain, the SSB occupies 240 consecutive subcarriers, and the 240 subcarriers are sequentially numbered in the order of increasing frequency as 0 to 239. Taking SSB #1 as an example, symbol #2 carries the PSS, the PSS occupies subcarriers #56 to #182, and subcarriers #0 to #55 and subcarriers #183 to #239 do not carry any information and can be set to 0. Symbol #3 and symbol #5 carry the PBCH, and every 4 consecutive subcarriers have one demodulation reference signal (DMRS) for decoding the PBCH. Symbol #4 carries the SSS and the PBCH, the SSS occupies subcarriers #56 to #182, the PBCH occupies subcarriers #0 to #47 and subcarriers #192 to #239, and the remaining subcarriers are set to 0.

[0125] It can be understood that based on the above-mentioned pattern of the SSB that can be transmitted by the network side, the terminal can start searching for the SSB on the synchronization raster according to the operating frequency band.

[0126] S702, the RAN device sends SSB-associated SIB1 to the terminal. Accordingly, the terminal receives SIB1 from the RAN device according to the configuration parameters.

[0127] Wherein, the terminal can blind detect a physical downlink control channel (PDCCH) according to the configuration parameters included in the MIB, and further obtain a downlink control information (DCI), which can be used to indicate time-frequency resources of a physical downlink shared channel (PDSCH) carrying SIB1, so that the terminal device can receive SIB1 according to the time-frequency resources.

[0128] S703, the RAN device sends SIB19 to the terminal. Accordingly, the terminal receives SIB19 from the RAN device.

[0129] It can be understood that the time-frequency resources for the terminal to receive SIB19 can be indicated by SIB1 or the configuration parameters in step S701, and no limitation is made in this regard.

[0130] S704, the terminal initiates RA according to the TA. Accordingly, the RAN device receives the RA message from the terminal.

[0131] The implementation of the terminal determining the TA will be described in detail below.

[0132] According to the relevant provisions of the 3GPP protocol, the TA in the NTN scenario can be determined according to formula (1).

[0133] Wherein, according to the definition of the frame structure in the 3GPP protocol, the minimum time unit is T c , and Δf max = 480·10 3 Hz, N f = 4096.

[0134] N TA : set to 0 when sending message 1 or message A in the initial access process, and can be updated by the random access response (RAR) corresponding to the message 1 or message A when the terminal sends a random access message subsequently.

[0135] N TA,offsetThe value of the TA-Granularity can be determined according to the working mode (e.g., time division duplex (TDD) or frequency division duplex (FDD)) and frequency band of the uplink transmission. 3GPP specifies the values corresponding to the relevant working mode and frequency band, which will not be described herein.

[0136] The value of the TA-Granularity can be calculated by the network side configured high layer parameters, e.g., TACommon, TACommonDrift, TACommonDriftVariation. The specific calculation method is specified by 3GPP protocol, which will not be described herein. In addition, if the network side does not configure the above high layer parameters, the value of the TA-Granularity is 0. The value of the TA-Granularity can be calculated by the network side configured high layer parameters, e.g., TACommon, TACommonDrift, TACommonDriftVariation. The specific calculation method is specified by 3GPP protocol, which will not be described herein. In addition, if the network side does not configure the above high layer parameters, the value of the TA-Granularity is 0.

[0137] The value of the TA-Granularity is related to the network side configured high layer parameters related to the satellite. For example, if the network side does not configure the high layer parameters related to the satellite ephemeris, the value of the TA-Granularity is 0. The value of the TA-Granularity is related to the network side configured high layer parameters related to the satellite. For example, if the network side does not configure the high layer parameters related to the satellite ephemeris, the value of the TA-Granularity is 0. The value of the TA-Granularity is related to the network side configured high layer parameters related to the satellite. For example, if the network side does not configure the high layer parameters related to the satellite ephemeris, the value of the TA-Granularity is 0.

[0138] It can be understood that the terminal can initiate RA according to the RA resource in the SIB1. Wherein, the terminal initiates RA, for example, can mean that the terminal sends a random access request, which can be message 1 (Msg1) or message A (MsgA). It can be understood that sending a random access request can be replaced by sending a preamble or sending a physical random access channel (PRACH).

[0139] In addition, the access network device can estimate the TA of the terminal through the preamble sent by the terminal, i.e., estimate the transmission delay caused by the distance between the terminal and the access network device, and notify the terminal through a timing advance command (TAC), so that the terminal can send uplink data according to the TAC, so that the above data of different terminal devices can be time-aligned when reaching the access network device.

[0140] S705, the RAN device access network device sends RAR to the terminal. Correspondingly, the terminal device receives RAR from the RAN device.

[0141] It can be understood that, for the terminal sending message A in S704, the RAR is message B. For the terminal sending message 1 in S704, the RAR can be message 2.

[0142] The following is described by taking message 2 as an example.

[0143] Optionally, message 2 includes uplink authorization, TAC, and temporary cell radio network temporary identity (C-RNTI). Wherein, the TAC is used for uplink time synchronization, the uplink authorization is used for the terminal to send message 3, and the temporary C-RNTI is used for the terminal to listen to the PDCCH used for scheduling message 4.

[0144] It can be understood that message B can be understood as the combination of message 2 and message 4.

[0145] Optionally, the method shown in FIG. 7 further includes steps S706 and S707.

[0146] S706, the terminal sends message 3 to the RAN device. Correspondingly, the RAN device receives message 3 from the terminal.

[0147] It can be understood that message 3 can include identity information (or called identification information) of the terminal, which is used for message 4 contention resolution

[0148] S707, in the case that the RAN device correctly receives message 3, the RAN device sends message 4 to the terminal. Correspondingly, the terminal receives message 4 from the RAN device. Wherein, message 4 can be called contention resolution message.

[0149] It should be understood that the above-mentioned message 3 and message 4 can carry control plane data and / or user plane data.

[0150] Third, positioning reference signal:

[0151] The positioning reference signal is defined in NR, which can be sent by the network side in the data transmission stage, and the terminal side receives the PRS and reports the measurement result to the network side, and then the network side estimates the position of the terminal according to the reported measurement result.

[0152] Taking a positioning method as an example, the positioning method is a downlink (DL)-time difference of arrival (TDOA) positioning method, a TRP at a RAN device side sends a PRS to a terminal, the terminal measures the PRS to obtain a DL-reference signal time difference (RSTD), and then reports the DL-RSTD to a location management function (LMF) at a network side, so that the LMF can determine a position of the terminal based on position information of the TRP and the DL-RSTD. In addition, the terminal can obtain the position of the terminal from the LMF.

[0153] To further enhance the above positioning process, the SSB can be used for positioning in the initial access process. It can be understood that the positioning based on the SSB can improve the positioning accuracy by increasing the bandwidth of the SSB.

[0154] For example, the SSB for positioning is similar to the aforementioned SSB for synchronization, for example, the SSB for positioning can include a PSS and / or an SSS. Alternatively, the SSB for positioning can also include a PBCH including an MIB. For details, refer to the foregoing description of the SSB for synchronization, which will not be described here.

[0155] In addition, the SSB with a large bandwidth described above can also be used for synchronization, that is, the terminal can perform time-frequency synchronization and determine its own position by using the SSB.

[0156] However, in the initial access process, some terminals can obtain useful self-position information through GNSS signals, and some UEs can not be able to obtain useful self-position information through GNSS. How to ensure that terminals with different requirements can determine TA is a problem to be solved at present.

[0157] Based on the above problems, the embodiments of the present application provide the following technical solutions, which can ensure that terminals with different requirements can determine TA in the initial access process. The technical solutions in the embodiments of the present application will be described below in combination with the accompanying drawings.

[0158] The embodiments of the present application are applicable to various communication systems, including: satellite communication systems, high altitude platform (HAPS) communication, unmanned aerial vehicle NTN systems, such as integrated communication and navigation (IcaN) systems, GNSS, and ultra-dense low-orbit satellite communication systems, and the like. Among them, the NTN system can be the NTN system introduced in the foregoing “NTN”, and the RAN architecture in the NTN system can be any one of the RAN architectures shown in FIGS. 3-5, or a future evolved RAN architecture, which is not limited. It should be understood that in addition to the NR system, the IoT system, and the future communication system, other communication systems, such as the LTE system, the vehicle to everything (V2X) system, the device-to-device (D2D) system, the machine to machine (M2M) communication system, and the like, can also introduce the NTN system. Alternatively, the other communication system can also be an O-RAN or a CRAN, which is not limited.

[0159] It should be understood that the architecture of the communication system and the service application scenario described in the embodiments of the present application are for more clearly illustrating the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. It can be known by those skilled in the art that, with the evolution of the communication architecture and the appearance of new service application scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0160] The embodiments of the present application provide a signal transmission method. Through the method, a terminal can receive a reference signal from a network device on at least one of a first resource and a second resource. The first resource is used to transmit a first reference signal, and the first reference signal is used for time and / or frequency synchronization. The second resource is used to transmit a second reference signal, and the second reference signal is used to determine the position of the terminal. Then, the terminal can select whether to receive the second reference signal on the second resource according to its own position requirements in the first resource and the second resource. For example, the terminal can receive the second reference signal on the second resource in the case that the terminal does not have a useful terminal position. Then, the TA can be determined according to the position of the terminal. For another example, in the case that the terminal has obtained a useful terminal position, the terminal can select not to receive the second reference signal on the second resource, so that the TA can be determined for terminals with different requirements.

[0161] The above method provided by the embodiments of the present application will be described below in conjunction with FIGS. 10-15.

[0162] It should be understood that the names of signals, parameters in signals, or information carried by signals between various devices or apparatuses in the following embodiments of the present application, or the like, are only examples, and other names can also be used in actual implementation, and the embodiments of the present application do not make specific limitations thereto.

[0163] In addition, the terminal and the network device are taken as the execution subject of the interaction in the embodiments of the present application, but the embodiments of the present application do not limit the execution subject of the interaction. For example, the method performed by the terminal in the embodiments of the present application can also be implemented by a communication module in the terminal or a circuit or a chip responsible for a communication function in the terminal (such as a modem chip (also referred to as a baseband chip), or a SoC chip containing a modem core, or a SIP chip); the method performed by the network device in the embodiments of the present application can also be implemented by a RAN device, or a module (such as a circuit, a chip or a chip system, etc.) in the RAN device, or a logic node, a logic module or software capable of implementing all or part of the function of the access network device.

[0164] FIG. 10 is a flow diagram of a signal transmission method according to an embodiment of the present application. As shown in FIG. 10, the method includes the following steps:

[0165] S1001, the network device transmits a first reference signal on a first resource and transmits a second reference signal on a second resource. Correspondingly, the terminal receives the reference signal from the network device on at least one of the first resource and the second resource.

[0166] The first resource is used for transmitting the first reference signal, and the first reference signal is used for time and / or frequency synchronization. The second resource is used for transmitting the second reference signal, and the second reference signal is used for determining the position of the terminal. At least one of the first reference signal and the second reference signal is associated with a preconfigured resource.

[0167] S1002, the terminal communicates with the network device according to the TA. Correspondingly, the network device can communicate with the terminal according to the preconfigured resource.

[0168] The TA is determined according to the reference signal received by the terminal on at least one of the first resource and the second resource.

[0169] The steps S1001 and S1002 are introduced respectively as follows.

[0170] For step S1001:

[0171] It should be understood that the terminal receiving the reference signal from the network device on at least one of the first resource and the second resource can be understood as that the terminal can selectively receive one or both of the two reference signals. For example, the terminal can receive the first reference signal on the first resource; for another example, the terminal can receive the second reference signal on the second resource; for yet another example, the terminal can receive the first reference signal on the first resource and receive the second reference signal on the second resource.

[0172] For example, the terminal can selectively receive the reference signal on at least one of the first resource and the second resource based on a location requirement.

[0173] For example, the terminal acquires the location of the terminal by the GNSS, and the terminal can receive the first reference signal on the first resource, so that the terminal can determine the TA based on the location of the terminal acquired by the GNSS and time and / or frequency synchronization by the first reference signal. It should be understood that the specific implementation of the terminal determining the TA can refer to the related description of formula (1), which will not be described here.

[0174] For another example, the terminal does not have the location of the terminal (for example, in the case that the GNSS signal is weak or there is no GNSS signal), and the terminal can receive the first reference signal on the first resource and receive the second reference signal on the second resource, and then the terminal can perform time and frequency synchronization according to the first reference signal and determine the location of the terminal according to the second reference signal, so as to determine the TA.

[0175] For another example, in the case that the terminal acquires the location of the terminal, the terminal can receive the second reference signal on the second resource in addition to receiving the first reference signal on the first resource, and then the terminal can further determine the location of the terminal according to the second reference signal and the location of the terminal.

[0176] In a possible implementation, the second reference signal is further used for time and / or frequency synchronization.

[0177] That is, time and / or frequency synchronization can also be performed according to the second reference signal, so as to facilitate the terminal to determine the TA.

[0178] For example, in the above example that the terminal does not have the location of the terminal, since the second signal is also used for time and frequency synchronization, the terminal can not receive the first reference signal on the first resource, but receive the second reference signal on the second resource, and then perform time synchronization, frequency synchronization and determine the location of the terminal according to the second reference signal, so as to determine the TA.

[0179] It should be understood that the above description that the terminal receives the reference signal on at least one of the first resource and the second resource is only an example, and can also include the following examples:

[0180] For example, if no useful terminal location is available, the terminal can receive a second reference signal on a second resource, and also receive a first reference signal on a first resource based on time and / or frequency synchronization requirements. For instance, the terminal can perform time synchronization based on the first reference signal, frequency synchronization based on the second reference signal, and determine its location. Alternatively, the terminal can perform frequency synchronization based on the first reference signal, time synchronization based on the second reference signal, and determine its location. Yet another example is that the terminal can perform time and frequency synchronization based on the first reference signal and determine its location based on the second reference signal.

[0181] In addition, the second reference signal can be used to assist in time and / or frequency synchronization, and the first reference signal can be used to assist in determining the location of the terminal.

[0182] It is understood that the above description of the terminal receiving a reference signal on at least one of the first and second resources based on its needs, and performing time synchronization, frequency synchronization, and determining the terminal's location based on the reference signal received on the at least one resource, are merely examples. The specific implementation depends on the actual implementation, and this application does not impose any specific limitations on this.

[0183] In other words, by transmitting a first reference signal on a first resource and a second reference signal on a second resource through a network device, a terminal can receive a reference signal on at least one of the first and second resources, and thus the terminal can selectively receive a reference signal on at least one of the first and second resources based on its needs.

[0184] It should be understood that since the network device can transmit both the first and second reference signals in addition to the first reference signal, the resources for transmitting the reference signals determined between the network device and the terminal should match in order for the terminal to selectively receive the first and second reference signals. Furthermore, embodiments of this application provide two methods for determining the first and second resources, which will be described below.

[0185] Method 1:

[0186] In the first mode, the second resource can be determined according to time domain resources and / or frequency domain resources occupied by the first reference signal. The time domain resources and / or frequency domain resources occupied by the first reference signal can be understood as follows: at the network device side, time domain resources and / or frequency domain resources used by the network device to send the first reference signal, for example, frames, half-frames, time slots, or symbols used by the network device to send the first reference signal, and for example, carriers, subcarriers, RBs, or GSCNs used by the network device to send the first reference signal; at the terminal side, time domain resources and / or frequency domain resources used by the terminal to receive the first reference signal, for example, frames, half-frames, time slots, or symbols used by the terminal to receive the first reference signal, and for example, carriers, subcarriers, RBs, or GSCNs used by the terminal to receive the first reference signal.

[0187] It should be understood that the above-mentioned time domain resources and / or frequency domain resources can also be replaced by reference positions (or reference points) in time and / or frequency, that is, other reference quantities for indicating time and / or frequency can be used instead of the above-mentioned frames or carriers, and embodiments of the present application do not make specific limitations in this regard.

[0188] It can be understood that in the first mode, the terminal can first receive the first reference signal on the first resource, and then determine the second resource according to the time domain resources and / or frequency domain resources used to receive the first reference signal. Similarly, the network device can determine the second resource according to the time domain resources and / or frequency domain resources used to send the first reference signal.

[0189] The first resource and the second resource in the first mode will be described in detail below.

[0190] For the first resource:

[0191] It can be understood that the terminal can use the synchronization raster introduced in step S701 of FIG. 7 to receive the first reference signal in a frequency sweeping manner, and then the first resource can be a protocol-defined synchronization raster. The network device can send the first reference signal on the candidate frequency points included in the synchronization raster. For details, please refer to the related description in step S701, which will not be repeated here.

[0192] In addition, the first reference signal may, for example, be the SSB for synchronization introduced in the foregoing part of the specific implementation mode, and can include PSS, SSS, and PBCH, etc. For details, please refer to the related description of SSB in S701, which will not be repeated here.

[0193] For the second resource:

[0194] In one possible implementation mode, the second resource is determined according to a first resource reference position and an offset. The first resource reference position is determined according to the time domain resources and / or frequency domain resources occupied by the first reference signal.

[0195] That is, the terminal can determine the second resource according to the time domain resource and / or the frequency domain resource occupied by the first reference signal, and can not need to blindly detect the second reference signal, thereby reducing the complexity of receiving the second reference signal and saving power consumption.

[0196] The first resource reference position and the offset will be introduced respectively.

[0197] For the first resource reference position:

[0198] In a possible implementation, the first resource reference position includes a first time domain resource reference position and / or a first frequency domain resource reference position. The first time domain resource reference position is determined according to the time domain resource occupied by the first reference signal. The first frequency domain resource reference position is determined according to the frequency domain resource occupied by the first reference signal.

[0199] That is, the first resource reference position can be a reference position in the time domain and / or a reference position in the frequency domain, thereby improving the flexibility of determining the second resource according to the first resource reference position.

[0200] For example, the first time domain resource reference position can be a starting time position or an ending time position in the time domain resource occupied by the first reference signal. For example, the time domain resource occupied by the first reference signal is the i th frame or on the i th frame, and the starting time position can be the starting time position (or the starting boundary of the i th frame) of the i th frame or the ending boundary of the i th frame. It should be understood that the first time domain resource reference position can also be a time position other than the starting boundary and the ending boundary in the i th frame (for example, the center time position of the i th frame), and the embodiments of the present application do not make specific limitations on this.

[0201] In addition, considering that one first reference signal can occupy multiple time domain resources (for example, time domain resources with a granularity of a time slot or a symbol), the first time domain resource reference position can be determined according to any time domain resource in the multiple time domain resources. For example, assuming that the first reference signal is an SSB as shown in FIG. 9, and occupies 4 symbols in the time domain, the first time domain resource reference position can be determined according to the starting time domain resource (that is, the starting symbol, that is, symbol #2) in the multiple time domain resources occupied by the first reference signal, or can be determined according to the ending symbol (that is, symbol #5), or can be determined according to any symbol other than symbol #2 and symbol #5 (for example, symbol #3 or symbol #4). In other words, the first time domain resource reference position can be the k th symbol of the j th time slot.

[0202] It should be understood that the above first time domain resource reference position is determined according to any one of the plurality of time domain resources, which can mean that the first time domain resource reference position can be a time position corresponding to any one of the time domain resources, for example, a start boundary, an end boundary, or other time positions in addition to the start boundary and the end boundary. For example, for the first time domain resource reference position determined according to symbol #2 in the above example, the first time domain resource reference position can be the start boundary, the end boundary, or other time positions (for example, the center time position of symbol #2) in addition to the start boundary and the end boundary of symbol #2. Similarly, the specific implementation of determining the first time domain resource reference position according to symbol #3, or symbol #4, or symbol #5 is similar to that of determining the first time domain resource reference position according to symbol #2, which will not be described here.

[0203] That is, the first time domain resource reference position can be determined according to the time domain resource occupied by the first reference signal, thereby improving the flexibility of determining the first time domain resource reference position.

[0204] For example, the first frequency domain resource reference position can be a center frequency position or a frequency domain start position of the frequency domain resource occupied by the first reference signal. It can be understood that the center frequency position or the frequency domain start position of the frequency domain resource occupied by the first reference signal can be understood as the center frequency or the frequency domain start position of the first reference signal. In addition, the center frequency of the first reference signal can also be replaced by GSCN, or other frequency units (for example, the center frequency of a subcarrier) that can represent the center frequency of the first reference signal, which is not limited in the embodiments of the present application.

[0205] For example, taking the SSB shown in FIG. 9 as the first reference signal, the first reference signal occupies 240 subcarriers (that is, subcarriers with indexes 0-239), and the center frequency of the first reference signal is the center frequency of the subcarrier with index 120. The frequency domain start position of the first reference signal is the start frequency of the subcarrier with index 0.

[0206] It should be understood that the above description of determining the first frequency domain resource reference position according to the frequency domain resource occupied by the first reference signal is only an example, and other ways of determining the first frequency domain resource reference position according to the frequency domain resource occupied by the first reference signal can also be used, for example, the first frequency domain resource reference position can be a frequency position other than the center frequency and the start frequency position of the frequency domain resource occupied by the first reference signal, which is not limited in the embodiments of the present application.

[0207] That is, the first frequency domain resource reference position can be determined according to the frequency domain resource occupied by the first reference signal, thereby improving the flexibility of determining the first frequency domain resource reference position.

[0208] For the offset:

[0209] In a possible implementation, the offset includes a time offset and / or a frequency offset compared with the first resource reference position. The time offset is used to determine the time domain resource occupied by the second reference signal. The frequency offset is used to determine the frequency domain resource occupied by the second reference signal.

[0210] That is, the time interval between the time domain resource occupied by the second reference signal and the first resource reference position, and / or the frequency interval between the frequency domain resource occupied by the second reference signal and the first resource reference position can be determined by the offset, and then the time domain resource and / or the frequency domain resource occupied by the second reference signal can be determined, so as to obtain the second resource used for transmitting the second reference signal. In addition, since the second resource is the time domain resource and / or the frequency domain resource occupied by the second reference signal, rather than the candidate resource (for example, the synchronization raster) for receiving the second reference signal by sweeping, the terminal can not receive the second reference signal by sweeping, so as to reduce the complexity, power consumption, and latency overhead of the terminal for receiving the second reference signal.

[0211] In a possible implementation, the time offset can be used to determine the start time position or the end time position of the time domain resource occupied by the second reference signal.

[0212] For example, as described above in relation to the first time domain resource reference position, it can be assumed that the first time domain resource reference position can be the start time position of the time domain resource occupied by the first reference signal, and the start time position of the time domain resource occupied by the second reference signal is the sum of the start time position of the time domain resource occupied by the first reference signal and the time offset. In addition, the time length (for example, the number of occupied symbols, or the number of occupied slots, etc.) corresponding to the time domain resource occupied by the second reference signal can be the time length corresponding to the time domain resource occupied by the first reference signal, or other lengths, which are not limited in the embodiments of the present application.

[0213] In addition, the time length corresponding to the time domain resource occupied by the second reference signal is predetermined by the protocol, or indicated by the network device, which is not limited in the embodiments of the present application.

[0214] It can be understood that the specific implementation of determining the end time position of the time domain resource occupied by the second reference signal by the terminal or the network device according to the time offset is similar to the implementation principle of determining the start time position of the time domain resource occupied by the second reference signal according to the time offset, which is not described herein again.

[0215] That is, the terminal or the network device can determine the time domain resource occupied by the second reference signal according to the first time domain resource reference position and the time offset, so as to improve the flexibility of determining the time domain resource occupied by the second reference signal.

[0216] In a possible implementation, the frequency offset is used to determine a center frequency or a frequency domain start position of the frequency domain resource occupied by the second reference signal.

[0217] For example, as described above in relation to the first frequency domain resource reference position, it can be assumed that the first frequency domain resource reference position is a center frequency of the frequency domain resource occupied by the first reference signal, and the center frequency of the frequency domain resource occupied by the second reference signal is a sum of the center frequency of the frequency domain resource occupied by the first reference signal and the frequency offset. In addition, the bandwidth (for example, the number of occupied subcarriers) corresponding to the frequency domain resource occupied by the second reference signal can be the bandwidth corresponding to the frequency domain resource occupied by the first reference signal, or another bandwidth, which is not limited in the embodiments of the present application.

[0218] In addition, the bandwidth corresponding to the frequency domain resource occupied by the second reference signal can be predetermined by a protocol or indicated by the network device, which is not limited in the embodiments of the present application.

[0219] It can be understood that the specific implementation of the terminal determining the frequency domain start position of the frequency domain resource occupied by the second reference signal according to the frequency offset is similar to the implementation principle of determining the center frequency of the frequency domain resource occupied by the second reference signal according to the frequency offset, which is not described herein again.

[0220] That is, the terminal or the network device can determine the frequency domain resource occupied by the second reference signal according to the first frequency domain resource reference position and the frequency offset, thereby improving the flexibility of determining the frequency domain resource occupied by the second reference signal.

[0221] In a possible implementation, the time offset is information of any one of the following granularities: a symbol, a slot, a subframe, or a frame, and the frequency offset is information of any one of the following granularities: a subcarrier, a carrier, an RB, or a GSCN.

[0222] That is, the time offset and / or the frequency offset can reuse the resource granularity defined in the existing protocol, thereby reducing the implementation complexity.

[0223] For example, it is assumed that the time offset is 0 and the frequency offset is 1, and the terminal can determine that the same time domain resource is occupied between the first reference signal and the second reference signal, and different frequency domain resources are occupied.

[0224] In addition, the frequency offset of 1 can be represented as a frequency domain resource of 1 granularity, for example, 1 subcarrier, 1 carrier, 1 RB, or 1 GSCN. Taking 1 GSCN as an example, the GSCN corresponding to the center frequency of the second reference signal is: the next GSCN of the GSCN corresponding to the center frequency of the first reference signal. It should be understood that the next GSCN can refer to the next candidate GSCN on the synchronization raster (i.e., the first resource used when the first reference signal is received). For example, when the terminal scans in the order of frequency from small to large on the synchronization raster (including N GSCNs, N is an integer greater than 2), assuming that the first reference signal is received on the i th GSCN, the terminal can receive the second reference signal on the i+1 th GSCN, which can be specifically referred to in FIG. 11.

[0225] Similarly, assuming that the terminal scans in the order of frequency from large to small, assuming that the first reference signal is received on the i th GSCN, the terminal can receive the second reference signal on the i-1 th GSCN.

[0226] It can be understood that the protocol can also predefine that when the frequency offset is 1, the next candidate GSCN is the GSCN in the frequency increasing direction, and when the offset is -1, the next candidate GSCN is the GSCN in the frequency decreasing direction, which is not limited in the embodiments of the present application.

[0227] It should be understood that when the frequency offset is expressed in subcarriers or RBs, the specific implementation can refer to the examples of expressing the frequency offset in GSCNs described above, which will not be described here.

[0228] For another example, assuming that the time offset is 4 and the frequency offset is 0, the terminal can determine that the same frequency domain resources are occupied between the first reference signal and the second reference signal, and different time domain resources are occupied.

[0229] In addition, the time offset of 4 can be represented as 4 granularities of time domain resources, for example, 4 frames, 4 time slots, or 4 symbols. Taking 4 symbols as an example, the starting symbol occupied by the second reference signal is: the next 4 symbols of the starting symbol occupied by the first reference signal. For example, as shown in FIG. 12, assuming that the first reference signal is the SSB shown in FIG. 9, the starting symbol occupied by the first reference signal is symbol #2, and the starting symbol occupied by the second reference signal is symbol #6.

[0230] In addition, the size of the time domain resource occupied by the second reference signal in FIG. 12 is only an example, and the size of the time domain resource occupied by the second reference signal can be pre-defined by the protocol or indicated by the network, which is not limited in the embodiments of the present application.

[0231] It should be understood that, in the case that the frequency offset is 0 (i.e., the frequency domain resources occupied between the first reference signal and the second reference signal are the same), the specific value of the time offset should be such that the time domain resources occupied by the second reference signal are different from the time domain resources occupied by the first reference signal. For example, if the first reference signal occupies 4 symbols, the time offset should be greater than or equal to 4 symbols. In addition, in the case that the network device transmits multiple first reference signals in the manner of a burst set, the specific value of the time offset should avoid collision with the time domain resources occupied by the multiple first reference signals.

[0232] For another example, assuming that the time offset is 1 and the frequency offset is 1, the terminal can determine that the first reference signal and the second reference signal occupy different frequency domain resources and at least partially the same time domain resources. It can be understood that, since the frequency domain resources occupied between the first reference signal and the second reference signal are different, the first reference signal and the second reference signal can be respectively transmitted through different frequency domain resources on the same time domain resource. In this scenario, the value of the time offset is not limited.

[0233] It should be understood that, on different time domain resources, the frequency domain resources occupied by the second reference signal can have the same distribution and size in the frequency domain. For example, the second reference signal can include a PSS and an SSS, as shown in (b) of FIG. 9, the PSS occupies symbol #2 and subcarrier #56-#182, and the SSS occupies symbol #5 and subcarrier #56-#182.

[0234] It can be understood that the frequency domain resources occupied by the second reference signal can also have different distribution and size in the frequency domain. For example, in the above example, the PSS can occupy symbol #2 and subcarrier #56-#182, and the SSS occupies symbol #5 and subcarrier #47-#192.

[0235] In addition, the above is only an exemplary description of the time offset and the frequency offset, and the time offset and the frequency offset can also be represented using other granularity information, which is not limited in the embodiments of the present application.

[0236] It should be understood that the above offset (e.g., including the time offset and / or the frequency offset) can be protocol predefined or network device indicated, which is not limited in the embodiments of the present application.

[0237] In a possible implementation, the offset is indicated by the first reference signal.

[0238] For example, the offset can be carried by the PBCH included in the first reference signal. For another example, the offset can be included in the MIB.

[0239] It should be understood that the specific implementation of the first reference signal indicating the offset is not limited in the embodiments of the present application.

[0240] That is, by indicating the offset through the first reference signal, the terminal can determine the second resource for receiving the second reference signal according to the offset and the time domain and / or frequency domain resource occupied by the first reference signal, and thus the modification on the terminal side can be reduced.

[0241] It can be understood that the network device indicating the offset through the first reference signal is only an example, and the offset can also be indicated through system information (for example, indicated through SIB1), so that the terminal can determine the second resource according to the offset included in SIB1 after receiving SIB1 according to the first reference signal, and then receive the second reference signal.

[0242] The content included in the second reference signal is described in detail below.

[0243] It should be understood that in the first mode, the second reference signal can include PSS and / or SSS, which can be used for positioning. Alternatively, the second reference signal can also include PBCH. The PBCH can include MIB. It can be understood that the MIB includes the system frame number and the configuration parameters (for example, including the indication information of the time-frequency resource) required to acquire SIB1 and other information. Since the terminal receives the first reference signal first in the first mode, the terminal can acquire the MIB through the first reference signal to complete the subsequent random access process. That is, on the basis that the first reference signal includes the PBCH, the second reference signal can not include the PBCH to reduce the time-frequency resource overhead of the second reference signal.

[0244] For example, FIG. 13 is a schematic diagram of the association relationship between the first reference signal and SIB1 according to an embodiment of the present application. As shown in FIG. 13, the center frequency of the first reference signal corresponds to the i-th GSCN, the first reference signal is used for time-frequency synchronization, the first reference signal includes configuration parameters for receiving SIB1, and indicates the second resource for receiving the second reference signal. The center frequency of the second reference signal corresponds to the j-th GSCN, and the second reference signal does not include PBCH.

[0245] The second mode is as follows:

[0246] It should be understood that the main difference between the second mode and the first mode is that the terminal can receive the first reference signal and the second reference signal through frequency sweeping. That is, compared with the first mode, the terminal does not need to receive the first reference signal first, but can select a resource from the first resource and the second resource to receive the reference signal.

[0247] The second resource is described first below.

[0248] In a possible implementation, the second resource is determined according to M candidate frequency points, and M is an integer greater than 1.

[0249] For example, the terminal can determine the second resource according to the M candidate frequencies. The network device can select at least one frequency point from the M candidate frequencies included in the second resource to send the second reference signal.

[0250] That is, the second resource is a candidate resource, and the terminal can receive the second reference signal in a frequency sweeping manner according to the second resource, and then can select one resource from the first resource and the second resource to receive the reference signal to perform time-frequency synchronization and determine TA, so as to reduce the time delay and power consumption of the terminal sending data to the network.

[0251] It can be understood that the frequency corresponding to each of the M candidate frequencies can be the center frequency or the frequency domain starting position of the second reference signal, and the embodiments of the present application do not make specific limitation.

[0252] In a possible implementation, the M candidate frequencies are determined according to a reference candidate frequency and a frequency interval. The frequency interval is used to indicate the frequency difference between any two candidate frequencies in the M candidate frequencies.

[0253] It can be understood that the second resource is similar to the aforementioned synchronization raster, and is composed of a series of discrete candidate frequencies, and there is a frequency interval between adjacent candidate frequencies, which is similar to the step in the aforementioned synchronization raster. In other words, the terminal and the network device can determine the M candidate frequencies according to the reference candidate frequency and the frequency interval.

[0254] That is, the terminal and the network device can determine the M candidate frequencies according to the reference candidate frequency and the frequency interval, which can reduce the implementation complexity of determining the second resource.

[0255] In a possible implementation, the frequency difference between any two candidate frequencies in the M candidate frequencies is information of any one of the following granularities: subcarrier, carrier, RB, or GSCN.

[0256] That is, the frequency difference between any two candidate frequencies in the M candidate frequencies can reuse the frequency domain resource granularity defined in the existing protocol, and then the implementation complexity can be reduced.

[0257] For example, the M candidate frequencies include candidate frequencies #1-#3, the frequency difference between candidate frequency #1 and candidate frequency #2 is 1200 kHz, and the frequency difference between candidate frequency #2 and candidate frequency #3 is 1200 kHz.

[0258] It should be understood that the frequency difference between any two candidate frequencies in the M candidate frequencies can also be a combination of the above different granularity frequency domain resources, so as to increase the flexibility of configuring the M candidate frequencies, and the embodiments of the present application do not make specific limitation.

[0259] In a possible implementation, the reference candidate frequency point comprises a candidate frequency point with the minimum frequency among the M candidate frequency points, and / or a candidate frequency point with the maximum frequency.

[0260] It can be understood that the terminal can determine M according to the working frequency band and the frequency corresponding to the reference candidate frequency point. In addition, after determining M, the terminal can determine the M candidate frequency points according to the reference candidate frequency point and the frequency interval. For example, for the reference candidate frequency point being the candidate frequency point with the minimum frequency among the M candidate frequency points, the terminal can determine the remaining M-1 candidate frequency points in turn according to the frequency interval. Similarly, for the reference candidate frequency point being the M candidate frequency points, the terminal can also determine the remaining M-1 candidate points in turn according to the frequency interval.

[0261] That is, the reference frequency point can be the candidate frequency point with the minimum frequency among the M candidate frequency points, and / or the candidate frequency point with the maximum frequency, thereby increasing the flexibility of determining the M candidate frequency points.

[0262] It should be understood that the reference candidate frequency point can also be any candidate frequency point among the M candidate frequency points, and the embodiments of the present application do not make specific limitations thereto.

[0263] It can be understood that the first resource and the second resource are similar, and both are used for the terminal to receive the reference signal by sweeping.

[0264] The first resource will be introduced below.

[0265] In a possible implementation, the first resource is determined according to N candidate frequency points, and any candidate frequency point among the N candidate frequency points is adjacent to any candidate frequency point among the M candidate frequency points.

[0266] It can be understood that N and M can be the same or different, and the embodiments of the present application do not make specific limitations thereto.

[0267] In addition, the N candidate frequency points and the M candidate frequency points are located at different frequency positions to avoid interference.

[0268] It should be understood that any candidate frequency point among the N candidate frequency points being adjacent to any candidate frequency point among the M candidate frequency points can mean that the N candidate frequency points and the M candidate frequency points are staggered in the frequency domain.

[0269] Exemplarily, as shown in FIG. 14, in the synchronization raster, the M candidate frequency points are sorted in ascending order of frequency as candidate frequency points #1-#3; the N candidate frequency points are sorted in ascending order of frequency as candidate frequency points #4-#6. The candidate frequency points #1-#6 are sorted in ascending order of frequency as candidate frequency point #1, candidate frequency point #4, candidate frequency point #2, candidate frequency point #5, candidate frequency point #3, and candidate frequency point #6.

[0270] That is, since the N candidate frequencies and the M candidate frequencies are staggered in the frequency domain, the terminal can search the first reference signal and the second reference signal in turn according to the frequency size, thereby reducing the complexity and power consumption of searching for the reference signal.

[0271] For example, taking the first reference signal as a synchronization SSB and the second reference signal as a synchronization positioning SSB (pos-SSB) as an example, based on the distribution of the M candidate frequencies and the N candidate frequencies in the frequency domain shown in FIG. 14, the parameters shown in Table 2 can be used to determine the first resource and the second resource.

[0272] Table 2

[0273] As shown in Table 2, represents the first GSCN corresponding to the first resource for receiving the synchronization SSB, represents the last GSCN corresponding to the first resource, represents the frequency interval corresponding to the first resource, that is, the frequency interval corresponding to the step. represents the granularity of adjacent GSCNs in the synchronization grid. M is a coefficient used to determine the frequency interval of the step T1 times. T is an integer greater than or equal to 1.

[0274] represents the first GSCN corresponding to the second resource for receiving the pos-SSB, represents the last GSCN corresponding to the second resource, and K is an integer greater than or equal to 1. represents the frequency interval corresponding to the second resource.

[0275] It should be understood that the values of T1 and T2 can be the same or different, depending on the actual implementation, and the embodiments of the present application do not make specific limitations thereon.

[0276] Taking K equal to 1 and the step between the synchronization SSB and the pos-SSB equal to 2 as an example, the GSCN range of the synchronization SSB is 7711-<2>-7811, and the GSCN range of the pos-SSB is 7712-<2>-7812. In this way, the corresponding GSCNs of the synchronization SSB and the pos-SSB are different, and the corresponding GSCNs of the two are adjacent. Specifically, the GSCN (that is, the N candidate frequencies) of the synchronization SSB is {7711, 7713, …, 7811}, and the GSCN (that is, the M candidate frequencies) of the pos-SSB is {7712, 7714, …, 7812}.

[0277] In addition, the reference candidate frequency in the N candidate frequencies can include: corresponding frequency point, and / or, corresponding frequency point, and / or, corresponding frequency point, and / or, corresponding frequency point.

[0278] In addition, the GSCN range in Table 2 is determined according to the operating frequency band of the terminal, and the GSCN range corresponding to different operating frequency bands is different. Here, the GSCN range corresponding to different operating frequency bands is uniformly described below.

[0279] It should be understood that the above arrangement of the M candidate frequency points and the N candidate frequency points in the frequency domain is only exemplary, and other arrangement modes can also be used, for example, the M candidate frequency points are not inserted between any candidate frequency point in the N candidate frequency points.

[0280] As shown in FIG. 15, the frequency band in which the M candidate frequency points are located does not overlap with the frequency band in which the N candidate frequency points are located, that is, any two candidate frequency points in the M candidate frequency points do not include any candidate frequency point in the N candidate frequency points.

[0281] Exemplarily, taking the first reference signal as the synchronization SSB and the second reference signal as the pos-SSB as an example, based on the distribution of the M candidate frequency points and the N candidate frequency points in the frequency domain shown in FIG. 15, the parameters shown in Table 3 can be used to define the first resource and the second resource.

[0282] Table 3

[0283] As shown in Table 3, indicates the first GSCN corresponding to the first resource, indicates the last GSCN corresponding to the first resource. indicates the first GSCN corresponding to the second resource, indicates the last GSCN corresponding to the second resource.

[0284] It should be understood that in the example shown in Table 3, the step length between the first resource and the second resource is only an example, and the step length between the first resource and the second resource can also be different, which is not limited.

[0285] Taking the step length of 1 as an example, the GSCN range of the synchronization SSB in Table 3 is 7711-<1>-7761, and the GSCN range of the pos-SSB is 7762-<2>-7812. The GSCN of the synchronization SSB is {7711, 7713, …, 7761}, and the range of the pos-SSB is {7762, 7714, …, 7812}.

[0286] In addition, the reference candidate frequency point in the N candidate frequency points can include the frequency point in Table 3. corresponding frequency point, and / or, corresponding frequency point, and / or, corresponding frequency point, and / or, corresponding frequency point.

[0287] It should be understood that the above-mentioned reference candidate frequency point and / or frequency interval can be protocol predefined, so that the terminal can determine the second resource without receiving the first reference signal, and then the terminal can select one of the first resource and the second resource to receive the reference signal, so that the terminal can select one of the first reference signal and the second reference signal to receive.

[0288] In a possible implementation, the second reference signal is also used for time and / or frequency synchronization.

[0289] It can be understood that, unlike the above-mentioned manner one, in the manner two, since the terminal can receive one of the first reference signal and the second reference signal, the second reference signal can be used for time and frequency synchronization in addition to being used for positioning, that is, the second reference signal can include a PBCH, which includes configuration parameters for acquiring a SIB1.

[0290] It should be understood that the preconfigured resource can also be acquired through the SIB1, and then the terminal can communicate with the network device according to the preconfigured resource. The preconfigured resource includes a random access resource and a preconfigured resource transmission. The terminal can access the network device according to the random access resource, for example, through the flow shown in FIG. 7. The preconfigured resource transmission includes, for example, a pre-configured uplink resource (PUR) transmission and a configured grant (CG) transmission (such as Type 1 CG). The preconfigured resource transmission can enable the terminal to immediately use the preconfigured time-frequency resource for PUSCH transmission without having to send a preamble first, thereby achieving the purpose of saving overhead and power consumption.

[0291] For example, the SIB1 can include a random access resource. Alternatively, the SIB1 can also include a preconfigured resource transmission resource, or the SIB1 can include configuration parameters for acquiring the preconfigured resource transmission resource.

[0292] That is, the second reference signal is also used for time and / or frequency synchronization, so that the terminal can receive one of the first reference signal and the second reference signal, and then communicate with the network device according to the preconfigured resource.

[0293] In a possible implementation, the system information associated between the first reference signal and the second reference signal is the same.

[0294] It can be understood that, different from the aforementioned manner one, in the manner two, since the terminal can receive one reference signal in the first reference signal and the second reference signal, the second reference signal can be used for time-frequency synchronization in addition to being used for positioning, that is, the second reference signal can include a PBCH including configuration parameters for acquiring SIB1.

[0295] For example, as shown in FIG. 15, the center frequency of the first reference signal corresponds to the i th GSCN, and the center frequency of the second reference signal corresponds to the j th GSCN. The first reference signal is used for time-frequency synchronization, and the first reference signal includes configuration parameters for receiving SIB1. The second reference signal also includes configuration parameters for receiving SIB1. It can be understood that the above i is not equal to j, and i and j are both positive integers.

[0296] That is, since the system information associated between the first reference signal and the second reference signal is the same, the terminal can select one of the first resource and the second resource to receive the reference signal to perform time-frequency synchronization and determine TA, so as to reduce the time delay and power consumption of the terminal in sending data to the network.

[0297] For step S1002:

[0298] It can be understood that, in step S1002, the manner in which the terminal determines the TA can refer to the formula (1) described in step S704 in FIG. 7, which will not be repeated here.

[0299] In addition, the terminal can determine the time-frequency resource for receiving system information according to the reference signal received in step S1001, and then receive the system information from the network device to obtain the parameters (for example, including ephemeris information) for determining the TA.

[0300] Optionally, the reference signal received in step S1001 includes time-frequency resources for acquiring SIB1, and the SIB1 includes random access resources and / or resources based on pre-configuration transmission. In addition, the SIB1 can also include time-frequency resources for acquiring SIB19, and the SIB19 includes NTN configuration parameters. For details, refer to the related description of SIB1 and SIB19 in FIG. 7, which will not be repeated here.

[0301] It can be understood that the communication between the terminal and the network device can include interaction of random access messages, or uplink transmission (such as PUSCH), and the like, which is not limited in the embodiments of the present application.

[0302] In addition, the terminal communicates with the network device, which can be random access or uplink transmission. The uplink transmission can be that the terminal sends a PUSCH to the network device. Alternatively, the terminal can also send a PUCCH to the network device.

[0303] The random access can be divided into two types. One is two-step random access, that is, the terminal sends a message A to the network device, and the network device sends a message B to the terminal. The other is four-step random access, which can be seen from FIG. 7, and will not be described here.

[0304] In the embodiments of the present application, the terminal can receive a reference signal from the network device on at least one of a first resource and a second resource. The first resource is used to transmit a first reference signal, and the first reference signal is used for time and / or frequency synchronization. The second resource is used to transmit a second reference signal, and the second reference signal is used to determine the position of the terminal. Therefore, the terminal can select whether to receive the second reference signal on the second resource according to its own needs for the position, so that terminals with different needs can determine the TA.

[0305] The embodiments of the present application also provide a communication device for implementing the above various methods. The communication device can be the terminal or the network device in the above method embodiments, or a device containing the terminal or the network device, or a component that can be used for the terminal or the network device. It can be understood that the communication device contains the corresponding hardware structure and / or software module for executing each function in order to implement the above functions. Those skilled in the art should easily realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0306] The embodiments of the present application can divide the functions of the communication device according to the above method embodiments, for example, each function module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be realized in the form of hardware or software function module. It should be noted that the division of the modules in the embodiments of the present application is illustrative, and is only a logical function division. There can be another division method when actually implemented.

[0307] For example, the communication device is the terminal or the network device in the method embodiments, and FIG. 16 is a structural schematic diagram of a communication device provided in an embodiment of the present application. As shown in FIG. 16, the communication device 1600 includes a processing module 1601 and a transceiver module 1602. The processing module 1601 is configured to perform the processing functions of the terminal or the network device in the method embodiments. The transceiver module 1602 is configured to perform the transceiving functions of the terminal or the network device in the method embodiments.

[0308] All the related contents of the steps in the method embodiments can be referred to the function description of the corresponding function modules, and will not be repeated here.

[0309] The communication device 1600 provided in the embodiment can perform the signal transmission method, and the technical effects that can be achieved by the communication device 1600 can be referred to the method embodiments, and will not be repeated here.

[0310] In a possible design, the transceiver module 1602 can include a receiving module and a sending module (not shown in FIG. 16). The transceiver module is configured to implement the sending function and the receiving function of the communication device 1600.

[0311] In a possible design, the communication device 1600 can further include a storage module (not shown in FIG. 16), which stores programs or instructions. When the processing module 1601 executes the programs or instructions, the communication device 1600 can perform the functions of the terminal or the network device in the method shown in FIG. 10.

[0312] It should be understood that the processing module 1601 involved in the communication device 1600 can be implemented by a processor or a processor-related circuit component, and can be a processor or a processing unit. The transceiver module 1602 can be implemented by a transceiver or a transceiver-related circuit component, and can be a transceiver or a transceiving unit.

[0313] Exemplarily, FIG. 17 is a structural schematic diagram of another communication device provided in an embodiment of the present application. The communication device can be a terminal or a network device, or can be a chip (system) or other components or assemblies that can be arranged in the terminal or the network device. As shown in FIG. 17, the communication device 1700 can include a processor 1701. In a possible design, the communication device 1700 can further include a memory 1702 and / or a transceiver 1703. The processor 1701 is coupled with the memory 1702 and the transceiver 1703, for example, can be connected through a communication bus.

[0314] The components of the communication device 1700 will be specifically introduced below in combination with FIG. 17:

[0315] The processor 1701 is a control center of the communication device 1700, which can be one processor or collectively refer to multiple processing elements. For example, the processor 1701 is one or more central processing units (CPUs), application specific integrated circuits (ASICs), or one or more integrated circuits configured to perform the functions of the embodiments of the present application, such as one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs).

[0316] In one possible design, the processor 1701 can perform various functions of the communication device 1700 by running or executing software programs stored in the memory 1702, and calling data stored in the memory 1702.

[0317] In a specific implementation, as an example, the processor 1701 can include one or more CPUs, such as CPU0 and CPU1 shown in FIG. 17.

[0318] In a specific implementation, as an example, the communication device 1700 can also include multiple processors, such as the processor 1701 and the processor 1704 shown in FIG. 17. Each of these processors can be a single-CPU or a multi-CPU. The processor here can refer to one or more devices, circuits, and / or processing cores for processing data (such as computer program instructions).

[0319] The memory 1702 is configured to store software programs for performing the solutions of the present application, and the processor 1701 is configured to control the execution. The specific implementation can refer to the above method embodiments, and will not be described here.

[0320] In a possible design, the memory 1702 can be a read-only memory (ROM) or another type of static storage device that can store static information and instructions, a random access memory (RAM) or another type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or another optical disk storage, an optical disk storage (including a compact disc, a laser disc, an optical disc, a digital versatile disc, a Blu-ray disc, and the like), a magnetic disk storage medium or another magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to this. The memory 1702 can be integrated with the processor 1701, or exist independently and be coupled to the processor 1701, and the embodiments of the present application do not make a specific limitation in this regard.

[0321] The transceiver 1703 is configured to communicate with another communication device. For example, the communication device 1700 is a terminal, and the transceiver 1703 can be configured to communicate with a network device. For another example, the communication device 1700 is a network device, and the transceiver 1703 can be configured to communicate with a terminal.

[0322] In a possible design, the transceiver 1703 can include a receiver and a transmitter (not shown in FIG. 17). The receiver is configured to implement the receiving function, and the transmitter is configured to implement the transmitting function.

[0323] In a possible design, the transceiver 1703 can be an input / output interface or an interface circuit, configured to input and / or output a signal.

[0324] In a possible design, the transceiver 1703 can be integrated with the processor 1701, or exist independently and be coupled to the processor 1701, and the embodiments of the present application do not make a specific limitation in this regard.

[0325] It should be noted that the structure of the communication device 1700 shown in FIG. 17 does not constitute a limitation on the communication device, and actually, the communication device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0326] In addition, the communication device 1700 can perform the signal transmission method described above, and thus the technical effects that can be achieved by the communication device can refer to the method embodiments described above, which will not be described here again.

[0327] In a possible implementation, the embodiment of the present application further provides a computer readable storage medium, which stores a computer program or instructions, and the computer program or instructions realize the functions of the method embodiments when executed by a computer.

[0328] In a possible implementation, the embodiment of the present application further provides a computer program product, which realizes the functions of the method embodiments when executed by a computer.

[0329] In a possible implementation, the embodiment of the present application further provides a communication system, which includes the terminal and the network device described in the method embodiments.

[0330] In a possible implementation, the embodiment of the present application further provides a communication method, which includes the method described in any of the method embodiments or any implementation thereof.

[0331] In the above embodiments, the implementation can be realized by software, hardware, firmware or any combination thereof, in whole or in part. When implemented by software, the implementation can be realized in the form of a computer program product, in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the whole or part of the flow or function according to the embodiments of the present application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another, for example, the computer instructions can be transferred from one website, computer, server or data center to another through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode. The computer readable storage medium can be any available medium that can be accessed by a computer or data storage device including one or more servers, data centers, etc. integrated with the medium. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium or a semiconductor medium (such as a solid state drive (SSD)) and the like.

[0332] Those skilled in the art can clearly understand that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0333] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0334] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. For example, the above-described device embodiments are only schematic, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0335] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0336] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically independently, or two or more units can be integrated into one unit.

[0337] If the functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the parts that contribute to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0338] Although the present application is described herein in conjunction with various embodiments, those skilled in the art, with the benefit of the drawings, the disclosure, and the appended claims, can understand and appreciate other variations of the disclosed embodiments that fall within the scope of the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. Measures recited in mutually different dependent claims can be combined and can be realized by a combination of measures.

[0339] Although the present application is described herein in conjunction with various embodiments, those skilled in the art, with the benefit of the drawings, the disclosure, and the appended claims, can understand and appreciate other variations of the disclosed embodiments that fall within the scope of the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. Measures recited in mutually different dependent claims can be combined and can be realized by a combination of measures.

[0339] Although the present application is described herein in conjunction with various embodiments, those skilled in the art, with the benefit of the drawings, the disclosure, and the appended claims, can understand and appreciate other variations of the disclosed embodiments that fall within the scope of the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. Measures recited in mutually different dependent claims can be combined and can be realized by a combination of measures.

Claims

1. A signal transmission method, characterized by, The method comprises: receiving a reference signal from a network device on at least one of a first resource and a second resource, the first resource being used for transmitting a first reference signal, the first reference signal being used for time and / or frequency synchronization, the second resource being used for transmitting a second reference signal, the second reference signal being used for determining a position of the terminal; communicating with the network device according to a timing advance (TA), the TA being determined according to the reference signal received on the at least one resource.

2. A signal transmission method characterized by, The method is applied to a network device, and the method comprises: transmitting a first reference signal on a first resource, and transmitting a second reference signal on a second resource, the first reference signal being used for time and / or frequency synchronization, the second reference signal being used for determining a position of a terminal, at least one of the first reference signal and the second reference signal being associated with a preconfigured resource; communicating with the terminal according to the preconfigured resource.

3. The method according to claim 1 or 2, characterized in that, The second resource is determined according to a first resource reference position and an offset, the first resource reference position being determined according to time domain resources and / or frequency domain resources occupied by the first reference signal.

4. The method of claim 3, wherein, The offset comprises a time offset and / or a frequency offset compared with the first resource reference position, the time offset being used for determining time domain resources occupied by the second reference signal, and the frequency offset being used for determining frequency domain resources occupied by the second reference signal.

5. The method according to claim 3 or 4, characterized in that, The time offset is information of any one of the following granularities: a symbol, a slot, a subframe, or a frame, and the frequency offset is information of any one of the following granularities: a subcarrier, a carrier, a resource block (RB), or a global synchronization channel number (GSCN).

6. The method according to any one of claims 3 to 5, characterized in that, The offset is indicated by the first reference signal.

7. The method according to claim 1 or 2, characterized in that, The second resource is determined according to M candidate frequencies, M being an integer greater than 1.

8. The method of claim 7, wherein, The M candidate frequencies are determined according to a reference candidate frequency and a frequency interval, the frequency interval being used for indicating a frequency difference between any two candidate frequencies in the M candidate frequencies.

9. The method of claim 8, wherein, The reference candidate frequency comprises a candidate frequency with the smallest frequency and / or a candidate frequency with the largest frequency in the M candidate frequencies.

10. The method according to any one of claims 7 to 9, characterized in that, The first resource is determined according to N candidate frequencies, any candidate frequency in the N candidate frequencies being adjacent to any candidate frequency in the M candidate frequencies.

11. The method according to any one of claims 1 to 10, characterized in that, The second reference signal is also used for time and / or frequency synchronization.

12. A communications device, characterized by The communication device comprises a module or unit for performing the method in any one of claims 1-11.

13. A communications device, characterized by The communication device comprises a processor configured to cause the communication device to perform the method in any one of claims 1-11 by means of a logic circuit and / or executing instructions.

14. A computer-readable storage medium, characterized in that, The computer-readable storage medium comprises instructions which, when executed by a processor, cause the method in any one of claims 1-11 to be implemented.

15. A computer program product, characterised in that, The computer program product comprises instructions which, when executed on a computer, cause the computer to perform the method in any one of claims 1-11.

16. A communication system, characterized by The communication system comprises terminals for performing the method according to any one of claims 1, 3-11 and network devices for performing the method according to any one of claims 2-11.

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