Communication method, apparatus, and system

Abstract

The present application relates to the technical field of communications. Disclosed are a communication method, apparatus and system. The method comprises: a first terminal device determines, on the basis of an identifier of the first terminal device, a first preamble corresponding to the identifier, and sends the first preamble, the first preamble being obtained on the basis of a first sequence, the first sequence being one of N sequences, and the N sequences being obtained on the basis of N1 recurrence formulas, N2 initial value sequences, and N3 cyclic shift values. According to the above method, the first preamble sent by the first terminal device corresponds to the identifier of the first terminal device, and thus transmission of an identifier of a terminal device on the basis of a preamble can be achieved. Furthermore, N2 and N3 are both greater than 1, that is, the number of initial value sequences and the number of cyclic shift values are both greater than 1. Therefore, the number of preambles can be expanded by means of the initial value sequences and the cyclic shift values, thereby facilitating the implementation of high capacity access by means of expanding the preambles.

Description

Communication method, apparatus and system

[0001] Cross Reference to Related Applications

[0002] This application claims priority to the Chinese Patent Application No. 202411345347.X, filed on September 24, 2024, and entitled “A communication method, apparatus and system”, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the field of communication technology, and in particular to a communication method, apparatus and system. BACKGROUND

[0004] With the continuous development of communication technology, network connection density will be improved in future communication systems. Specifically, massive communication as an extension of massive machine type communication (mMTC) puts forward new requirements for network capability, such as the requirement for network connection density of 10 6 -10 8 devices / km, so the number of terminal devices accessing the network device will further increase. In terms of terminal types, in the massive connection scenario, there will be multiple terminal device types, in addition to traditional Internet of Things devices, new Internet of Things devices will also be introduced.

[0005] For the access of massive Internet of Things devices, one possible evolution scheme is to transmit the identifier of the terminal device in the first step of the random access procedure. However, the related implementation of transmitting the identifier of the terminal device in the first step of the random access procedure still needs further research. SUMMARY

[0006] The present application provides a communication method, apparatus and system for implementing the transmission of the identifier of the terminal device based on the preamble.

[0007] In a first aspect, an embodiment of the present application provides a communication method, which can be executed by a first communication device. In the present application, the "first communication device" can refer to a communication device (e.g., a first terminal device), a component (e.g., a processor, a chip, or a chip system) in the communication device, or a logic module or software capable of realizing all or part of the functions of the communication device. For example, in the method provided in the first aspect, a first terminal device determines a first preamble corresponding to an identifier of the first terminal device according to the identifier, and transmits the first preamble. The first preamble is obtained according to a first sequence, the first sequence is one of N sequences, and the N sequences are obtained according to N1 recursive formulas, N2 initial value sequences, and N3 cyclic shift values. N1 is an integer greater than or equal to 1, and N2 and N3 are integers greater than 1.

[0008] According to the above method, the first preamble transmitted by the first terminal device corresponds to the identifier of the first terminal device, so that the identifier of the terminal device can be transmitted based on the preamble. Further, since N2 and N3 are both greater than 1, that is, the number of initial value sequences and the number of cyclic shift values are both greater than 1, the number of preambles can be expanded by using the initial value sequences and the cyclic shift values, so that the large-capacity access can be realized by expanding the preambles.

[0009] In a possible design, the first preamble is transmitted by transmitting the first preamble based on a square wave.

[0010] In this way, the power consumption of the first terminal device can be saved, and the complexity of the transmitter and the receiver can be reduced.

[0011] In a possible design, the first preamble corresponding to the identifier of the first terminal device is determined according to the identifier of the first terminal device and a one-to-one correspondence between a plurality of identifiers and a plurality of preambles.

[0012] In a possible design, the first sequence is a Z4 sequence.

[0013] In a possible design, the first preamble is obtained according to the first sequence, including that the first preamble is obtained according to the first sequence and a second sequence, or the first preamble is the first sequence. The second sequence is one of M sequences, and the M sequences are obtained according to M1 recursive formulas, a first initial value sequence, and M2 cyclic shift values. M1 is an integer greater than or equal to 1, and M2 is an integer greater than 1.

[0014] In a possible design, the second sequence is an m sequence.

[0015] In a possible design, the first preamble is obtained according to a first sequence and a second sequence, including: the first preamble is obtained by scrambling the first sequence with the second sequence.

[0016] In a possible design, the first preamble is obtained by scrambling the first sequence with the second sequence, including: the first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], and the second sequence is denoted as [c(n)], where n=0, 1, 2,..., L-1. where α is a complex constant.

[0017] In a possible design, the method further includes: determining to transmit the identifier based on the preamble.

[0018] In a possible design, the determining to transmit the identifier based on the preamble includes: receiving indication information from the network device, where the indication information is used to instruct the first terminal device to transmit the identifier based on the preamble.

[0019] In a possible design, the N sequences have a length of 127, and the N2 initial value sequences [x(0), x(1), x(2), x(3), x(4), x(5), x(6)] include at least one of the following:

[0020] [1,0,0,0,0,0,0],[3,0,0,0,0,0,0],[1,0,0,0,2,2,2],[3,2,0,0,0,0,0],[1,2,2,2,0,0,0],[1,0,0,0,0,0,2],[3,0,0,0,0,0,2],[3,2,2,2,0,0,0],[1,2,0,0,0,0,0],[3,0,0,0,2,2,2],[1,2,0,2,0,2,0],[3,2,2,0,0,0,0],[1,2,2,2,2,2,2],[1,2,2,0,0,2,2],[3,0,2,2,0,0,0],[1,2,0,2,0,0,0],[1,0,2,0,0,0,0],[1,0,2,0,2,0,2],[1,0,0,0,2,0,2],[3,2,0,0,2,2,2],[1,0,2,2,2,2,0],[1,0,0,0,0,2,0],[3,0,0,0,0,2,0],[3,2,2,2,0,0,2],[3,2,0,0,0,0,2],[3,0,0,0,2,2,0],[1,0,0,0,0,2,2],[3,0,0,0,0,2,2],[1,0,0,0,2,2,0],[1,2,0,0,0,0,2],[1,2,2,2,0,0,2],[3,2,2,2,2,2,2],[1,2,2,0,0,0,0],[3,2,0,2,0,2,0],[3,0,2,2,2,2,0],[1,2,0,0,2,2,2],[3,0,0,0,2,0,2],[3,0,2,0,2,0,2],[3,0,2,0,0,0,0],[3,2,0,2,0,0,0],[1,0,2,2,0,0,0],[3,2,2,0,0,2,2],[1,0,0,2,0,2,2],[1,0,0,2,0,0,0],[1,2,0,2,2,0,2],[1,0,2,2,0,0,2],[3,2,2,0,2,0,2],[3,2,0,0,2,2,0],[3,0,2,0,2,2,2],[3,2,2,2,2,2,0],[3,2,2,0,2,2,2],[3,2,0,0,2,0,2],[3,0,0,2,0,2,2],[1,2,0,2,2,2,2],[1,2,0,0,2,2,0],[3,0,0,2,0,2,0],[1,0,2,2,2,2,2],[1,2,2,2,0,2,0],[1,2,2,2,2,0,2],[1,2,2,0,2,0,0],[3,0,2,2,2,2,2],[3,0,2,0,2,0,0],[3,2,2,0,0,0,2],[1,0,2,0,2,2,2],[3,0,0,2,0,0,0],[1,0,2,0,0,2,0],[3,2,0,0,0,2,2],[1,0,0,0,2,0,0],[3,0,2,0,0,2,2],[3,2,2,0,2,0,0],[3,0,0,0,2,0,0],[3,2,2,2,0,2,2],[3,2,0,0,0,2,0],[1,2,0,0,0,2,0],[1,2,2,2,0,2,2],[1,0,2,0,2,0,0],[3,2,0,2,0,0,2],[3,2,2,0,0,2,0],[1,2,0,2,0,2,2],[1,0,2,0,0,0,2],[1,2,2,2,2,2,0],[3,2,2,2,0,2,0],[1,2,0,0,0,2,2],[1,2,2,0,0,0,2],[3,0,2,2,0,0,2],[3,0,2,0,0,0,2],[3,2,0,2,0,2,2],[1,2,2,0,0,2,0],[1,2,0,2,0,0,2],[1,2,2,0,2,0,2],[3,2,0,2,2,0,2],[1,0,0,2,0,2,0],[1,0,2,0,0,2,2],[3,0,2,0,0,2,0],[3,2,0,2,2,2,2],[3,2,2,2,2,0,2],[1,2,0,0,2,0,2],[1,2,2,0,2,2,2],[3,0,0,2,2,2,2],[3,2,2,2,2,0,0],[1,2,2,2,2,0,0],[3,0,2,2,0,2,0],[1,2,2,0,2,2,0],[3,2,0,0,2,0,0],[3,0,2,2,2,0,2],[1,0,0,2,2,0,0],[1,2,0,2,2,2,0],[3,0,0,2,2,0,2],[3,0,0,2,0,0,2],[1,0,0,2,2,2,2],[3,2,0,2,2,0,0],[1,0,0,2,2,2,0],[3,0,0,2,2,0,0],[1,0,2,2,2,0,0],[1,0,2,2,0,2,2],[3,0,2,2,2,0,0],[3,0,2,2,0,2,2],[3,2,0,2,2,2,0],[3,2,2,0,2,2,0],[1,0,0,2,0,0,2],[1,2,0,0,2,0,0],[1,0,2,2,2,0,2],[3,0,2,0,2,2,0],[1,2,0,2,2,0,0],[1,0,2,0,2,2,0],[1, 0, 0, 2, 2, 0, 2], [3, 0, 0, 2, 2, 2, 0], [1, 0, 2, 2, 0, 2, 0].

[0021] In a second aspect, the embodiments of the present application provide a communication method, which can be executed by a second communication device. In the present application, the "second communication device" can refer to a communication device (for example, a network device), a component (for example, a processor, a chip, or a chip system) in the communication device, or a logic module or software capable of realizing all or part of the functions of the communication device. For example, in the method provided in the third aspect, a network device receives a first preamble from a first terminal device; synchronizes with the first terminal device according to the first preamble, and determines an identity of the first terminal device; wherein the first preamble is obtained according to a first sequence, the first sequence is one of N sequences, and the N sequences are obtained according to N1 recursive formulas, N2 initial value sequences, and N3 cyclic shift values, N1 is an integer greater than or equal to 1, and N2 and N3 are integers greater than 1.

[0022] In a possible design, the identity of the first terminal device is determined according to the first preamble, including: the identity of the first terminal device corresponding to the first preamble is determined according to the one-to-one correspondence between the first preamble and a plurality of identities and a plurality of preambles.

[0023] In a possible design, the first sequence is a Z4 sequence.

[0024] In a possible design, the first preamble is obtained according to a first sequence, including: the first preamble is obtained according to a first sequence and a second sequence, or the first preamble is the first sequence; the second sequence is one of M sequences, and the M sequences are obtained according to M1 recursive formulas, a first initial value sequence, and M2 cyclic shift values, M1 is an integer greater than or equal to 1, and M2 is an integer greater than 1.

[0025] In a possible design, M1=1, the M1 recursive formulas include a first recursive formula; the method further includes: receiving a second preamble from a second terminal device; and synchronizing with the second terminal device according to the second preamble; wherein the second preamble is obtained according to the first recursive formula, the first initial value sequence, and a first cyclic shift value.

[0026] In a possible design, the second sequence is an m sequence.

[0027] In one possible design, the first cyclic shift value is different from the M2 cyclic shift values, or the first cyclic shift value is one of the M2 cyclic shift values.

[0028] In one possible design, the first preamble is derived from a first sequence and a second sequence, including that the first preamble is scrambled with the second sequence on the first sequence.

[0029] In one possible design, the first preamble is derived from a first sequence and a second sequence, including that the first preamble is scrambled with the second sequence on the first sequence. where α is a complex constant.

[0030] In one possible design, the method further includes sending, to the first terminal device, indication information, where the indication information is used to indicate that the first terminal device transmits the identity based on a preamble.

[0031] In one possible design, the N sequences have a length of 127, and the N2 initial value sequences [x(0), x(1), x(2), x(3), x(4), x(5), x(6)] include at least one of the following:

[0032] [1,0,0,0,0,0,0],[3,0,0,0,0,0,0],[1,0,0,0,2,2,2],[3,2,0,0,0,0,0],[1,2,2,2,0,0,0],[1,0,0,0,0,0,2],[3,0,0,0,0,0,2],[3,2,2,2,0,0,0],[1,2,0,0,0,0,0],[3,0,0,0,2,2,2],[1,2,0,2,0,2,0],[3,2,2,0,0,0,0],[1,2,2,2,2,2,2],[1,2,2,0,0,2,2],[3,0,2,2,0,0,0],[1,2,0,2,0,0,0],[1,0,2,0,0,0,0],[1,0,2,0,2,0,2],[1,0,0,0,2,0,2],[3,2,0,0,2,2,2],[1,0,2,2,2,2,0],[1,0,0,0,0,2,0],[3,0,0,0,0,2,0],[3,2,2,2,0,0,2],[3,2,0,0,0,0,2],[3,0,0,0,2,2,0],[1,0,0,0,0,2,2],[3,0,0,0,0,2,2],[1,0,0,0,2,2,0],[1,2,0,0,0,0,2],[1,2,2,2,0,0,2],[3,2,2,2,2,2,2],[1,2,2,0,0,0,0],[3,2,0,2,0,2,0],[3,0,2,2,2,2,0],[1,2,0,0,2,2,2],[3,0,0,0,2,0,2],[3,0,2,0,2,0,2],[3,0,2,0,0,0,0],[3,2,0,2,0,0,0],[1,0,2,2,0,0,0],[3,2,2,0,0,2,2],[1,0,0,2,0,2,2],[1,0,0,2,0,0,0],[1,2,0,2,2,0,2],[1,0,2,2,0,0,2],[3,2,2,0,2,0,2],[3,2,0,0,2,2,0],[3,0,2,0,2,2,2],[3,2,2,2,2,2,0],[3,2,2,0,2,2,2],[3,2,0,0,2,0,2],[3,0,0,2,0,2,2],[1,2,0,2,2,2,2],[1,2,0,0,2,2,0],[3,0,0,2,0,2,0],[1,0,2,2,2,2,2],[1,2,2,2,0,2,0],[1,2,2,2,2,0,2],[1,2,2,0,2,0,0],[3,0,2,2,2,2,2],[3,0,2,0,2,0,0],[3,2,2,0,0,0,2],[1,0,2,0,2,2,2],[3,0,0,2,0,0,0],[1,0,2,0,0,2,0],[3,2,0,0,0,2,2],[1,0,0,0,2,0,0],[3,0,2,0,0,2,2],[3,2,2,0,2,0,0],[3,0,0,0,2,0,0],[3,2,2,2,0,2,2],[3,2,0,0,0,2,0],[1,2,0,0,0,2,0],[1,2,2,2,0,2,2],[1,0,2,0,2,0,0],[3,2,0,2,0,0,2],[3,2,2,0,0,2,0],[1,2,0,2,0,2,2],[1,0,2,0,0,0,2],[1,2,2,2,2,2,0],[3,2,2,2,0,2,0],[1,2,0,0,0,2,2],[1,2,2,0,0,0,2],[3,0,2,2,0,0,2],[3,0,2,0,0,0,2],[3,2,0,2,0,2,2],[1,2,2,0,0,2,0],[1,2,0,2,0,0,2],[1,2,2,0,2,0,2],[3,2,0,2,2,0,2],[1,0,0,2,0,2,0],[1,0,2,0,0,2,2],[3,0,2,0,0,2,0],[3,2,0,2,2,2,2],[3,2,2,2,2,0,2],[1,2,0,0,2,0,2],[1,2,2,0,2,2,2],[3,0,0,2,2,2,2],[3,2,2,2,2,0,0],[1,2,2,2,2,0,0],[3,0,2,2,0,2,0],[1,2,2,0,2,2,0],[3,2,0,0,2,0,0],[3,0,2,2,2,0,2],[1,0,0,2,2,0,0],[1,2,0,2,2,2,0],[3,0,0,2,2,0,2],[3,0,0,2,0,0,2],[1,0,0,2,2,2,2],[3,2,0,2,2,0,0],[1,0,0,2,2,2,0],[3,0,0,2,2,0,0],[1,0,2,2,2,0,0],[1,0,2,2,0,2,2],[3,0,2,2,2,0,0],[3,0,2,2,0,2,2],[3,2,0,2,2,2,0],[3,2,2,0,2,2,0],[1,0,0,2,0,0,2],[1,2,0,0,2,0,0],[1,0,2,2,2,0,2],[3,0,2,0,2,2,0],[1,2,0,2,2,0,0],[1,0,2,0,2,2,0],[1, 0, 0, 2, 2, 0, 2], [3, 0, 0, 2, 2, 2, 0], [1, 0, 2, 2, 0, 2, 0].

[0033] It can be understood that the communication method provided by the second aspect corresponds to the communication method provided by the first aspect, and the beneficial effects of the related technical features in the second aspect can be referred to the description of the first aspect.

[0034] In the third aspect, the present application provides a communication device, which has the functions related to the first aspect or the second aspect, for example, the communication device includes modules or units or means for performing the operations related to the first aspect or the second aspect. The functions or units or means can be implemented by software or hardware, or by executing corresponding software by hardware.

[0035] In a possible design, the communication device includes a processing unit and a communication unit. The communication unit can be configured to transceive signals to implement communication between the communication device and other devices. The processing unit can be configured to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit can correspond to the operations related to the first aspect or the second aspect.

[0036] In a possible design, the communication device includes a processor. The processor can be configured to be coupled with a memory. The memory can store computer programs or instructions necessary for implementing the functions related to the first aspect or the second aspect. The processor can execute the computer programs or instructions stored in the memory. When the computer programs or instructions are executed, the communication device can implement the method in any possible design or implementation manner of the first aspect or the second aspect.

[0037] In a possible design, the communication device includes a processor and a memory. The memory can store computer programs or instructions necessary for implementing the functions related to the first aspect or the second aspect. The processor can execute the computer programs or instructions stored in the memory. When the computer programs or instructions are executed, the communication device can implement the method in any possible design or implementation manner of the first aspect or the second aspect.

[0038] In a possible design, the communication device includes a processor and an interface circuit. The processor can be configured to communicate with other devices through the interface circuit, and perform the method in any possible design or implementation manner of the first aspect or the second aspect.

[0039] It can be understood that, in the third aspect, the processor can be implemented by hardware or software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, or the like. When implemented by software, the processor can be a general-purpose processor, which implements the above-mentioned method by reading software codes stored in the memory. In addition, the processor can be one or more, and the memory can be one or more. The memory can be integrated with the processor, or the memory can be arranged separately from the processor. In the implementation process, the memory can be integrated on the same chip as the processor, or can be arranged on different chips, and the embodiments of the present application do not limit the type of memory and the arrangement mode of the memory and the processor.

[0040] In a fourth aspect, the present application provides a communication system, which can include a first communication device and a second communication device; wherein the first communication device is configured to perform the method of the first aspect, and the second communication device is configured to perform the method of the second aspect.

[0041] In a fifth aspect, the present application provides a computer-readable storage medium, which stores a computer program (or computer-readable instructions). When a computer reads and executes part or all of the computer-readable instructions, the method in any possible design of the first aspect or the second aspect is performed.

[0042] For example, the computer-readable storage medium can be any available medium that can be accessed by a computer. For example, but not limited to: the computer-readable medium can include a non-transitory computer-readable medium, a random access memory (RAM), a read-only memory (ROM), an electrically EPROM (EEPROM), a CD-ROM or other optical disk storage, a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program codes in the form of instructions or data structures and can be accessed by a computer.

[0043] In a sixth aspect, the present application provides a computer program product, which, when read and executed by a computer, causes the method in any possible design of the first aspect or the second aspect to be performed.

[0044] In a seventh aspect, the present application provides a chip (or a chip system), which includes a processor and a memory coupled with the processor, and the memory stores a computer program; the processor is configured to call part or all of the computer program in the memory, so that the method in any possible design of the first aspect or the second aspect is performed. BRIEF DESCRIPTION OF DRAWINGS

[0045] FIG. 1 is a schematic diagram of an architecture of a communication system to which embodiments of the present application are applied;

[0046] FIG. 2 is a schematic diagram of a random access procedure provided by an embodiment of the present application;

[0047] FIG. 3A is a schematic diagram of a symbol group provided by an embodiment of the present application;

[0048] FIG. 3B is a schematic diagram of a guard band provided by an embodiment of the present application;

[0049] FIG. 4 is a schematic diagram of a basic structure of a feedback shift register provided by an embodiment of the present application;

[0050] FIG. 5 is a schematic diagram of a flow corresponding to a communication method provided by an embodiment of the present application;

[0051] FIG. 6 is a possible exemplary block diagram of an apparatus involved in an embodiment of the present application;

[0052] FIG. 7 is a schematic diagram of a structure of a communication apparatus provided by an embodiment of the present application. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. The present application will present various aspects, embodiments or features around a system which can include a plurality of devices, components, modules, etc. It should be understood and appreciated that each system can include additional devices, components, modules, etc., and / or can not include all the devices, components, modules, etc. discussed in connection with the drawings. In addition, combinations of these solutions can also be used.

[0054] In the embodiments of the present application, the words “exemplary”, “for example”, and the like are used to mean example, illustration, or description. Any embodiment or design solution described as “exemplary” in the present application should not be interpreted as more preferred or having more advantages than other embodiments or design solutions. Rather, the word “exemplary” is used to present the concept in a specific manner. In the embodiments of the present application, “of”, “corresponding” and “corresponding” are sometimes mixed. It should be pointed out that when the distinction is not emphasized, the meanings expressed are consistent.

[0055] The technical solutions of the embodiments of the present application can be applied to various wireless communication systems, such as a universal mobile telecommunications system (UMTS), a wireless local area network (WLAN), a short-range wireless communication system (such as a sidelink, wireless fidelity (Wi-Fi), Bluetooth, and the like), a wired network, a vehicle to everything (V2X) communication system, a device-to-device (D2D) communication system, a vehicle networking communication system, a 4th generation (4G) mobile communication system (such as a long term evolution (LTE) system), an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD), a worldwide interoperability for microwave access (WiMAX) communication system, a 5th generation (5G) mobile communication system (such as a new radio (NR) system), a future communication system, or other similar communication systems, and the like, without limitation. The embodiments of the present application are described by taking a communication system shown in FIG. 1 as an example, and when the technical solutions of the embodiments of the present application are applied to other communication systems, devices, components, modules, and the like in the embodiments can be replaced by corresponding devices, components, modules in other communication systems, without limitation.

[0056] FIG. 1 is a schematic diagram of an architecture of a communication system to which embodiments of the present application are applied. As shown in FIG. 1, the communication system includes an access network 100. Optionally, the communication system can also include a core network 200 and an Internet 300. The access network 100 can include at least one network device, such as 110a and 110b in FIG. 1, and at least one terminal device, such as 120a-120j in FIG. 1. Among them, 110a is a base station, 110b is a micro station, 120a, 120e, 120f and 120j are mobile phones, 120b is a car, 120c is a fuel dispenser, 120d is a home access point (HAP) arranged indoors or outdoors, 120g is a notebook computer, 120h is a printer, and 120i is a drone. Among them, the same terminal device or network device can provide different functions in different application scenarios. For example, the mobile phones in FIG. 1 are 120a, 120e, 120f and 120j. The mobile phone 120a can access the base station 110a, connect to the car 120b, communicate directly with the mobile phone 120e and access the HAP. The car 120b can access the HAP and communicate directly with the mobile phone 120a. The mobile phone 120f can access the micro station 110b, connect to the notebook computer 120g and connect to the printer 120h. The mobile phone 120j can control the drone 120i.

[0057] (1) Network device

[0058] A network device is a network-side device with wireless transceiving function. The network device can be a device in a radio access network (RAN) that provides wireless communication function for a terminal device, referred to as a RAN device. The RAN can be an access network in the 3rd generation partnership project (3GPP), such as 4G, 5G or future network. The RAN can also be an open RAN (O-RAN or ORAN), a cloud radio access network (CRAN), or a communication network of two or more of the above networks.

[0059] The RAN device can also be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next generation NodeB (gNB) in a 5G mobile communication system, a base station in a future mobile communication system or an access node in a WiFi system, etc.

[0060] The RAN device can also be a module or unit that completes the functions of the base station part, for example, can be a central unit (CU), can also be a distributed unit (DU), and can also be a radio unit (RU). The CU here completes the functions of the radio resource control protocol (RRC) and the PDCP of the base station, and can also complete the function of the service data adaptation protocol (SDAP); the CU can be further divided into a CU control panel (CP) (CU-CP) and a CU user panel (UP) (CU-UP). The DU completes the functions of the RLC layer and the MA layer of the base station, and can also complete part of the physical layer or all the physical layer functions. For specific descriptions of the above-mentioned protocol layers, please refer to the relevant technical specifications of 3GPP. The CU and the DU can be separately arranged, or can also be included in the same network element, such as a baseband unit (BBU). The RU can be included in a radio frequency device or a radio frequency unit, such as a remote radio unit (RRU), an active antenna processing unit (AAU), or a remote radio head (RRH). In different systems, the CU, the DU or the RU can also have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, the CU can also be referred to as an O-CU (open CU), the DU can also be referred to as an O-DU, and the RU can also be referred to as an O-RU. Any one of the CU (or CU-CP, CU-UP), the DU and the RU in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module. The RAN device can be a macro base station (such as 110a in FIG. 1), can also be a micro base station or an indoor station (such as 110b in FIG. 1), and can also be a relay node or a donor node, etc. The embodiments of the present application do not limit the specific technologies and specific device forms adopted by the network device.

[0061] In the embodiments of the present application, the functions of the network device can also be executed by a module (such as a chip) in the network device, or can also be executed by a control subsystem containing the functions of the network device. The control subsystem containing the functions of the network device here can be a control center in the above-mentioned application scenarios such as smart grid, industrial control, intelligent transportation, and smart city.

[0062] (2) Terminal device

[0063] A terminal device is a user-side device with wireless transceiving function. The terminal device can also be referred to as a terminal, a user equipment (UE), a mobile station, a mobile terminal, etc. The terminal device can be widely applied in various scenarios, such as device-to-device (D2D), vehicle to everything (V2X) communication, machine-type communication (MTC), internet of things (IOT), virtual reality, augmented reality, industrial control, automatic driving, remote medical treatment, smart power grid, smart furniture, smart office, smart wear, smart transportation, smart city, etc. The terminal device can be a mobile phone, a tablet computer, a computer with wireless transceiving function, a wearable device, a vehicle, a drone, a helicopter, an airplane, a ship, a robot, a mechanical arm, a smart home device, etc. For example, the terminal device in the embodiments of the present application can be a terminal device (which can be referred to as an IOT device) in an IOT scenario, such as an electronic tag, which can also be referred to as a tag.

[0064] In the embodiments of the present application, the device for implementing the function of the terminal device can be the terminal device, or a device capable of supporting the terminal device to implement the function, such as a chip system or a combination device or component that can implement the function of the terminal device, which can be installed in the terminal device. The embodiments of the present application do not limit the specific technology and specific device form adopted by the terminal device.

[0065] In the embodiments of the present application, the function of the terminal device can also be executed by a module (such as a chip or a modem) in the terminal device, or by a device containing the function of the terminal device.

[0066] The network device and the terminal device can be fixed in position or movable. The network device and the terminal device can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; can also be deployed on the water surface; can also be deployed on an airplane, a balloon and a man-made satellite in the air. The embodiments of the present application do not limit the application scenarios of the network device and the terminal device.

[0067] The roles of the network device and the terminal device can be relative. For example, the helicopter or the drone 120i in FIG. 1 can be configured as a mobile network device, and for a terminal device 120j that accesses the wireless access network 100 through the 120i, the terminal device 120i is a network device; but for the network device 110a, the 120i is a terminal device, that is, the 110a and the 120i communicate through a wireless air interface protocol. Of course, the 110a and the 120i can also communicate through an interface protocol between network devices and network devices, and in this case, the 120i is also a network device relative to the 110a. Therefore, the network device and the terminal device can be collectively referred to as a communication apparatus, and the 110a and the 110b in FIG. 1 can be referred to as a communication apparatus with a network device function, and the 120a-120j in FIG. 1 can be referred to as a communication apparatus with a terminal device function.

[0068] The network device and the terminal device, the network device and the network device, and the terminal device and the terminal device can communicate through an authorized frequency spectrum, can communicate through an unlicensed frequency spectrum, or can simultaneously communicate through the authorized frequency spectrum and the unlicensed frequency spectrum, and the specific implementation is not limited.

[0069] The network architecture and the service scenario described in the present application are used to more clearly illustrate 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. Those skilled in the art can know that, with the evolution of the network architecture and the appearance of new service scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0070] In the communication system shown in FIG. 1, the terminal device can interact with the network device through a random access process to achieve uplink synchronization with the network device. The random access process refers to a process from the start of sending a random access preamble by the terminal device to attempt to access the network to the establishment of a basic signaling connection with the network device. The random access preamble is carried on a physical random access channel (PRACH) and is used to initiate the random access process. The random access preamble can be referred to as a random access preamble sequence, or a preamble sequence, or a preamble.

[0071] (1) Random access process of LTE / NR

[0072] According to whether the preamble is selected by the terminal device itself, the random access process can be divided into a contention-based random access process and a non-contention-based random access process. The following describes a possible implementation of the random access process in LTE / NR by taking the contention-based random access process as an example.

[0073] FIG. 2 is a schematic diagram of a random access procedure provided by an embodiment of the present application. As shown in FIG. 2, the random access procedure includes the following steps:

[0074] S200, the network device sends configuration information of random access to the terminal device, and accordingly, the terminal device can receive the configuration information from the network device. This step can be a preparation before performing the random access procedure, and does not belong to the steps included in the random access procedure.

[0075] For example, the network device can send the configuration information of random access to the terminal device through a system message. The configuration information can include information 1, which is used to configure a plurality of PRACH occasions (ROs). One RO can be understood as a block of time-frequency resources, which is used to transmit a preamble.

[0076] The configuration information can also include information 2, such as a logical root index number, which is used to determine a sequence set (or a preamble set) of the current cell. For details, refer to the description below.

[0077] In addition, the configuration information can also be used to configure other possible information, such as the correspondence between a plurality of ROs and a synchronization signal block (SS) / physical broadcast channel (PBCH) block (SS / PBCH block).

[0078] S201, the terminal device sends a preamble to the network device. The preamble can be referred to as the first message or message 1 (Msg1) of the random access procedure.

[0079] Specifically, the terminal device can receive a plurality of SS / PBCH blocks sent by the network device, and select a target SS / PBCH block from the plurality of SS / PBCH blocks according to the measurement values (such as the reference signal receiving power (RSRP) of the plurality of SS / PBCH blocks) of the plurality of SS / PBCH blocks. Further, the terminal device selects a preamble from the preamble set (such as including 64 preambles) of the current cell, and then sends the preamble on the RO corresponding to the target SS / PBCH block.

[0080] S202, after detecting the preamble sent by the terminal device, the network device sends a random access response (RAR) to the terminal device. The random access response can be referred to as the second message or message 2 (Msg2) of the random access procedure.

[0081] Exemplarily, after receiving the preamble on the RO corresponding to the target SS / PBCH block, the network device can determine the downlink beam for communication with the terminal device as the beam corresponding to the target SS / PBCH block, and then transmit the RAR to the terminal device using the beam corresponding to the target SS / PBCH block.

[0082] Exemplarily, the RAR includes a timing advance (TA), and the TA is used for uplink synchronization between the terminal device and the network device.

[0083] S203, the terminal device transmits uplink signaling to the network device according to the TA. The uplink signaling can be referred to as the 3rd message or message 3 (Msg3) of the random access process.

[0084] S204, the network device transmits a contention resolution message to the terminal device. Accordingly, the terminal device can receive the contention resolution message from the network device, and if it is determined that the random access conflict is won according to the contention resolution message, it is determined that the random access is successful; otherwise, the terminal device determines that the random access fails. The contention resolution message can be referred to as the 4th message or message 4 (Msg4) of the random access process.

[0085] It can be understood that the above S201 to S204 are the four steps of the random access process, and the above process can also be referred to as the four-step random access process. The random access process shown in FIG. 2 is only one possible example of the process, and the embodiments of the present application are not limited thereto.

[0086] (2) Preamble of LTE / NR

[0087] The preamble set of each cell in LTE / NR can include 64 preambles, i.e., 64 sequences, which are obtained by cyclically shifting at least one root sequence, and the root sequence is a ZC sequence.

[0088] Exemplarily, the 64 sequences in the preamble set can be divided into sequences for contention-based random access and sequences for non-contention-based random access, the preambles for contention-based random access can be further divided into Group A and Group B, Group B is used for a scenario where the data amount of MSG3 is large and the path loss is small, and Group A is used for other scenarios that are not suitable for Group B. Therefore, for the contention-based random access shown in FIG. 2, the terminal device can determine whether to use Group A or Group B according to the data amount of Msg3 and the size of the path loss; if it is determined to use Group A, a preamble is randomly selected from Group A, and if it is determined to use Group B, a preamble is randomly selected from Group B.

[0089] The implementation of the terminal device obtaining the preamble set will be described below in combination with the following two steps (i.e., Step 1 and Step 2).

[0090] Step 1: The terminal device generates a root sequence [X u (n)] as a reference sequence.

[0091] Exemplarily, after receiving the logical root index number (denoted as i) from the network device, the terminal device can query a predefined table to obtain a physical root index number (denoted as u) according to the logical root index number, and then generate a root sequence according to the physical root index number. The specific generation formula (i.e., the generation formula of the ZC sequence) is as follows:

[0092] wherein L is the length of the root sequence. For example, the length of the root sequence is 139 or 839.

[0093] When the length of the root sequence is 139, the value range of the physical root index number is 1 to 138. The predefined table is shown in Table 1.

[0094] Table 1: Correspondence table of logical root index number and physical root index number

[0095] Step 2: The terminal device cyclically shifts the root sequence [X u (n)] to generate 64 sequences [X u,v (n)]. If the number of sequences generated by cyclically shifting the root sequence [X u (n)] is less than 64, the next root sequence is generated, and the next root sequence is cyclically shifted until 64 sequences are generated.

[0096] wherein the sequence [X u,v (n)] can be generated by the following formula:

[0097] X u,v (n) = X u ((n+C v ) mod L RA

[0098] The above C v is a cyclic shift value, such as C v = vN CS , represents rounding down L / N CS ; N CS is a cyclic shift interval, and the cyclic shift interval is related to a cell radius, an uplink processing delay of a terminal device, and the like, and a specific value of the cyclic shift interval can be configured by a network device.

[0099] The following takes the length of a root sequence as 139 as an example to illustrate how to obtain 64 sequences in a preamble set.

[0100] A terminal device receives a logical root index number 20, obtains a physical root index number 11 by querying Table 1, and further generates a root sequence [X 11 (n)]. Further, assuming that N CS is 4, v = 0, 1, 2, …, 34.

[0101] The first sequence: v = 0, C v = vN CS = 0, X 11,0 (n) = X 11 (n), that is, the first sequence is the root sequence [X 11 (n)];

[0102] The second sequence: v = 1, C v = vN CS = 4, X 11,1 (n) = X 11 ((n+4) mod 139;

[0103] The third sequence: v = 2, C v = vN CS = 8, X 11,2 (n) = X 11 ((n+8) mod 139;

[0104] And so on.

[0105] The thirty-fifth sequence: v = 34, C v = vN CS = 136, X 11,34 (n) = X 11 ((n+136) mod 139.

[0106] Since the number of sequences generated by cyclically shifting the root sequence [X 11 (n)] is less than 64, the next root sequence is generated and cyclically shifted. The physical root index number of the next root sequence is 128 (i.e., the logical root index number is 21), and thus the next root sequence is [X 128 (n)].

[0107] The 36th sequence: v = 0, C v = vN CS = 0, X 128,0 (n) = X 128 (n), i.e., the 36th sequence is the root sequence [X 128 (n)].

[0108] The 37th sequence: v = 1, C v = vN CS = 4, X 128,1 (n) = X 128 ((n+4) mod 139.

[0109] By analogy.

[0110] The 64th sequence: v = 28, C v = vN CS = 112, X 128,28 (n) = X 128 ((n+112) mod 139, and thus 64 sequences are obtained.

[0111] It can be understood that the above is described by taking the terminal device generating 64 sequences as an example. In other examples, the terminal device can also determine the physical root index number and the cyclic shift value corresponding to each sequence of the 64 sequences without actually generating the sequences; after the terminal device selects one sequence (such as sequence a), the sequence a is generated according to the physical root index number and the cyclic shift value corresponding to the sequence a.

[0112] (3) Random access procedure and preamble of narrowband internet of things

[0113] Narrow Band-Internet of Things (NB-IOT) is a technology introduced by 3GPP to support ultra-low complexity and low throughput Internet of Things, mainly targeting low power consumption, wide coverage, long distance, low bandwidth Internet of Things services. In order to meet some business needs of Internet of Things, NB-IOT makes some adjustments to the random access process on the basis of LTE. The random access process of NB-IOT is similar to that of LTE / NR, and also includes the four steps described above. The difference lies in that the preamble of NB-IOT is different from that of LTE / NR. The preamble of NB-IOT is not generated by ZC sequence, but is transmitted in a single-tone manner based on frequency hopping. That is, it occupies one subcarrier on each symbol, and the subcarrier spacing can be 3.75 kilohertz (kHz). The preamble of NB-IOT includes 4 symbol groups, as shown in FIG. 3A. Each symbol group includes 1 cyclic prefix (CP) and 5 symbols, and 1 (i.e. high level) is transmitted on each symbol. Among them, the CP can be a short CP or a long CP. When the symbol length is 266.7 microseconds (us), the length of the short CP is 66.7 us, and the length of the long CP is 266.7 us.

[0114] Taking a total bandwidth of 1 resource block (RB) as an example, since 1 RB includes 12 subcarriers, a maximum of 12 terminal devices (i.e. NB-IOT devices) can be multiplexed within the total bandwidth. In addition, since the crystal oscillator stability of NB-IOT devices (such as tags) is poor, the frequency offset after downlink synchronization calibration is about 20ppm (error within 20 parts per million), i.e. the frequency offset changes in a large range (i.e. large frequency offset), and a large frequency offset needs to reserve a guard band. As shown in FIG. 3B, if two subcarriers are reserved as a guard band between every two available subcarriers, the maximum number of NB-IOT devices that can be multiplexed within 1 RB is 4.

[0115] With the continuous development of communication technology, the network connection density will be improved in future communication systems. Specifically, as an extension of massive machine type communication, massive communication puts forward new requirements for network capability, such as the requirement for network connection density of 10 6 -10 8Therefore, the number of terminal devices accessing network devices will further increase in the future. In terms of terminal types, in the massive connection scenario, there will be various terminal device types, in addition to traditional IOT devices (such as NB-IOT devices), new IOT devices (such as Ambient IOT devices) will also be introduced. Ambient IOT is a low-end IOT that is not involved in 3GPP before, which does not need to be powered (pure batteryless devices) or is based on limited energy storage capability (devices with limited energy storage capability), obtains energy from the environment, and realizes small data signal transmission through backscattering, low-power radio frequency transmission (only radio frequency signal amplification or independent signal generation).

[0116] For the access of massive IOT devices, a possible evolution scheme is that the terminal device transmits an identifier (or user identifier) in the first step of the random access process. The identifier can be randomly generated by the terminal device or generated based on the device identifier of the terminal device, and the specific implementation is not limited; accordingly, in the second step of the random access process, the network device sends Msg2 to the terminal device, and Msg2 carries the identifier received by the network device. If the terminal device determines that the identifier carried in Msg2 is the same as the identifier of the terminal device, it can be considered that the random access is successful. In this way, compared with the four-step random access process described above, the random access process can be simplified, and the power consumption of the terminal device can be reduced.

[0117] Based on this, the embodiments of the present application will study the related implementation of transmitting the identifier of the terminal device in the first step of the random access process. It should be noted that the embodiments of the present application do not limit the specific implementation of other steps of the random access process, and the "Msg2 carries the identifier received by the network device" described above is only one possible example.

[0118] Exemplarily, in the first step of the random access process, the identifier of the terminal device is transmitted. One possible implementation is to explicitly carry the identifier of the terminal device through a MAC control element (CE), and another possible implementation is to transmit the identifier of the terminal device based on a preamble. Since the transmission power of the IOT device is limited, compared with explicit transmission, transmitting the identifier of the terminal device based on the preamble can obtain better performance, therefore, in the scheme provided by the embodiments of the present application, the identifier of the terminal device will be transmitted based on the preamble.

[0119] Further, on one hand, due to the limited transmission power of the Internet of Things device, the preamble (complex sequence) generated based on the ZC sequence in LTE / NR cannot be applied to the Internet of Things device. On the other hand, due to the large number of Internet of Things devices, for example, the identifier of the Internet of Things device includes 16 bits, when transmitting the identifier of the terminal device based on the preamble, in order to meet the requirement of transmitting the identifier of 16 bits, there need to be 2 16 =65536 preambles (such as each preamble transmits the identifier of one terminal device); and the NB-IOT in the foregoing can multiplex at most 12 terminal devices (in the case of reserving a guard band, the number of multiplexed terminal devices is smaller), which cannot meet the capacity requirement of the Internet of Things device on the preamble. Therefore, on the basis of transmitting the identifier of the terminal device based on the preamble, the present embodiment further studies the related implementation of how to expand the capacity of the preamble to realize large-capacity access.

[0120] The communication method provided by the present embodiment is described below in combination with specific embodiments. The communication method provided by the present embodiment relates to a first communication device and a second communication device. The first communication device is the sending side of the preamble, and the second communication device is the receiving side of the preamble. For example, the first communication device is a first terminal device or a component in the first terminal device, such as a chip (such as a baseband chip) or a chip system arranged in the first terminal device; and the second communication device is a network device or a component in the network device, such as a chip or a chip system arranged in the network device. In the present embodiment, the first communication device is taken as the first terminal device, and the second communication device is taken as the network device.

[0121] First, the related terms or technical features involved in the present embodiment are explained. When not specifically explained, these explanations are to support the meaning of the related terms and make the present embodiment easier to understand, and should not be regarded as a strict limitation on the protection scope required by the present application.

[0122] (1) Sequence

[0123] The "sequence" in the present embodiment includes one or more elements. The element can be represented as a complex number, including a real part and an imaginary part; or the element can also be represented as a real number, which is not specifically limited.

[0124] For example, the sequence [s(n)] includes L elements, L is an integer greater than 1. n belongs to [0, …, L-1], that is, n∈[0, …, L-1]. The "…" in [0, …, L-1] represents the integers between 0 and L-1, for example, when L=5, n∈[0, 1, 2, 3, 4]. The L elements in [s(n)] can be s(0), …, s(L-1) respectively; in other words, the element with the number n in [s(n)] can be s(n). It can be understood that the embodiments of the present application take the numbering mode with the starting number 0 and the increment of 1 as an example, but it is not limited thereto. For example, the numbering mode can also be that the starting number is 1 and the increment is 1. For another example, the numbering mode can also be that the starting number is X and the increment is 1, X is an integer greater than 1. "[·]" and "{·}" can be used interchangeably to represent multiple elements, which can be understood as a set, a group, or a sequence, etc., without limitation.

[0125] Exemplarily, the sequence related by the embodiments of the present application includes m sequence, Z3 sequence and Z4 sequence, which are briefly described here.

[0126] M sequence: the m sequence is the abbreviation of the longest linear feedback shift register sequence, which is the longest period sequence generated by a shift register with linear feedback. Generally speaking, the longest period generated by a v-level linear feedback shift register is equal to 2 v -1. FIG. 4 is the basic structure of a feedback shift register, the bit data used for initialization is stored in the memory, and a new value is generated by a feedback function and supplemented to the memory. Assuming that the feedback function is an exclusive OR operation on all the bits in the memory, that is , then a1, a2, …, a n is the initial value sequence, and the output sequence is The length of the output sequence is 2 v -1.

[0127] It can be understood that the m sequence is determined by the initial value sequence stored in the register and the primitive polynomial, the value set of the initial value is {0, 1}, and the order of the primitive polynomial is the highest power in the polynomial. For example, the recursive formula corresponding to the primitive polynomial f(x)=x 7 +x+1 is s(t)+s(t-6)+s(t-7)=0, since the binary addition is defined as modulo 2 addition, the above recursive formula can be converted to s(t)=s(t-6)+s(t-7), that is, the recursive formula corresponding to the primitive polynomial f(x)=x 7 +x+1 is s(t)=s(t-6)+s(t-7). In the embodiments of the present application, the recursive formula corresponds to the primitive polynomial one by one, and "recursive formula" and "primitive polynomial" can be replaced by each other.

[0128] Z3 sequence: Z3 sequence is a ternary sequence, and the value set of the initial value is {0, 1, 2}. The period of the Z3 sequence is (3 n -1) / 2. In actual use, the sequence element 2 in the Z3 sequence can be changed to -1, that is, the value set of the element of the Z3 sequence is {-1, 0, 1}.

[0129] Z4 sequence: Z4 sequence is a quaternary sequence, and the period of the Z4 sequence is the same as that of a binary Gold sequence (the Gold sequence can be regarded as an m sequence with different primitive polynomials, which is obtained by performing XOR operation on elements) of the same length. The value set of the initial value is {0, 1, 2, 3}. The Z4 sequence can be generated by a cyclic shift register, and the generation of the Z4 sequence is extremely similar to that of the m sequence. The difference is that the Z4 sequence is defined on a four-element ring {0, 1, 2, 3}, and therefore the addition and subtraction are all modulo 4. For example, the primitive polynomial of the Z4 sequence is f(x) = x 7 + 2x 4 + x + 3, which can also be expressed as 10020013. The recursive formula corresponding to the primitive polynomial is s(t) = mod(2s(t-3) + 3s(t-6) + s(t-4), 4).

[0130] In actual use of the Z4 sequence, the Z4 sequence (the value set of the element of the Z4 sequence is {0, 1, 2, 3}) can be modulated, such as mapping the element “0” to “1”, mapping the element “1” to “j”, mapping the element “2” to “-1”, and mapping the element “3” to “-j”. The value set of the element of the modulated Z4 sequence is {1, j, -1, -j}.

[0131] (2) Capacity comparison of different sequences

[0132] For the m sequence: for the same recursive formula, the m sequences generated by different initial values are cyclically shifted sequences of each other. For example, the length of the m sequence is 63, and there are 64 (2 6) initial value sequences, and the m sequences generated by the 64 initial value sequences are cyclically shifted sequences of each other. For example, initial value sequence 1 is [c(5), c(4), c(3), c(2), c(l), c(0)] = [0, 0, 0, 0, 0, 1], and m sequence 1 is generated according to initial value sequence 1 and the recursive formula; initial value sequence 2 is [c(5), c(4), c(3), c(2), c(l), c(0)] = [0, 0, 0, 0, 1, 0], and m sequence 2 is generated according to initial value sequence 2 and the recursive formula; m sequence 1 and m sequence 2 are cyclically shifted sequences of each other, that is, m sequence 2 can be obtained by cyclically shifting m sequence 1. Therefore, it can be considered that the m sequence has only one initial value sequence. As shown in Table 2, for the m sequence, one recursive formula can obtain about sequences, sequences, L represents the sequence length, N CS represents the cyclic shift interval. CS

[0133] For the Z4 sequence: for example, the length of the Z4 sequence is 64, and there are 4096 (4 6 ) initial value sequences, and the Z4 sequences generated by 65 initial value sequences of the 4096 initial value sequences are not cyclically shifted sequences of each other, and the Z4 sequences generated by the other initial value sequences are cyclically shifted sequences of the Z4 sequences generated by the 65 initial value sequences. For another example, the length of the Z4 sequence is 127, and there are 4 7 initial value sequences, and the Z4 sequences generated by 129 initial value sequences of the 4 7 initial value sequences are not cyclically shifted sequences of each other, and the Z4 sequences generated by the other initial value sequences are cyclically shifted sequences of the Z4 sequences generated by the 129 initial value sequences. Therefore, for the Z4 sequence with a length of L = 2 n -1, there are about L initial value sequences. As shown in Table 2, for the Z4 sequence, one recursive formula can obtain about sequences.

[0134] Similarly, the Z3 sequence has two initial value sequences, and therefore, as shown in Table 2, for the Z3 sequence, one recursive formula can obtain about sequences. In addition, for the Z3 sequence scrambled by the m sequence, about sequences can be obtained. For the Z4 sequence scrambled by the m sequence, about sequences can be obtained.

[0135] Table 2: Capacity comparison of different sequences ​

[0136] It should be understood that the capacity listed in Table 2 is only an estimated value, and the actual capacity can be slightly different from the values listed in Table 2.

[0137] FIG. 5 is a flowchart of a communication method provided by an embodiment of the present application. As shown in FIG. 5, the flowchart can include the following steps:

[0138] S501, the first terminal device determines a first preamble corresponding to the identifier of the first terminal device according to the identifier of the first terminal device.

[0139] For example, the first terminal device determines a first preamble corresponding to the identifier of the first terminal device according to the identifier of the first terminal device and a one-to-one correspondence between a plurality of identifiers and a plurality of preambles, the plurality of identifiers including the identifier of the first terminal device, and the plurality of preambles including the first preamble.

[0140] (1) Introduction to preamble

[0141] Taking the number of preambles as W, W preambles are obtained according to N sequences, N sequences are obtained according to N1 recursive formulas, N2 initial value sequences and N3 cyclic shift values, N1 is an integer greater than or equal to 1, and W, N, N2 and N3 are integers greater than 1. In this way, since the number of initial value sequences and the number of cyclic shift values are both greater than 1, the number of preambles can be expanded by initial value sequences and cyclic shift values, so as to facilitate the expansion of preambles to realize large-capacity access.

[0142] Since the cross-correlation between different Z4 sequences (or Z3 sequences) based on the same recursive formula is relatively low, and the cross-correlation between different Z4 sequences (or Z3 sequences) based on different recursive formulas is relatively high, in order to ensure the detection performance of the preamble (the lower the cross-correlation between different preambles, the better the detection performance), N1 can be equal to 1, and in the embodiments of the present application, “N1=1” is mainly taken as an example for description.

[0143] The N sequences can be Z3 sequences or Z4 sequences (the Z4 sequences here can refer to modulated Z4 sequences, and the modulation of the Z4 sequences can refer to the description above, and the Z4 sequences below can be understood as modulated Z4 sequences). Taking the N sequences as Z4 sequences as an example, when the length of the N sequences is 127 (that is, the length of each sequence in the N sequences is 127), the initial value sequence of the Z4 sequence can be represented as [x(0), x(1), x(2), x(3), x(4), x(5), x(6)], and the N2 initial value sequences include at least one of the following: [1, 0, 0, 0, 0, 0, 0], [3, 0, 0, 0, 0, 0, 0], [1, 0, 0, 0, 2, 2, 2], [3, 2, 0, 0, 0, 0, 0], [1, 2, 2, 2, 0, 0, 0], [1, 0, 0, 0, 0, 0, 2], [3, 0, 0, 0, 0, 0, 2], [3, 2, 2, 2, 0, 0, 0], [1, 2, 0, 0, 0, 0, 0], [3, 0, 0, 0, 2, 2, 2], [1, 2, 0, 2, 0, 2, 0], [3, 2, 2, 0, 0, 0, 0], [1, 2, 2, 2, 2, 2, 2], [1, 2, 2, 0, 0, 2, 2], [3, 0, 2, 2, 0, 0, 0], [1, 2, 0, 2, 0, 0, 0], [1, 0, 2, 0, 0, 0, 0], [1, 0, 2, 0, 2, 0, 2], [1, 0, 0, 0, 2, 0, 2], [3, 2, 0, 0, 2, 2, 2], [1, 0, 2, 2, 2, 2, 0], [1, 0, 0, 0, 0, 2, 0], [3, 0, 0, 0, 0, 2, 0], [3, 2, 2, 2, 0, 0, 2], [3, 2, 0, 0, 0, 0, 2], [3, 0, 0, 0, 2, 2, 0], [1, 0, 0, 0, 0, 2, 2], [3, 0, 0, 0, 0, 2, 2], [1, 0, 0, 0, 2, 2, 0], [1, 2, 0, 0, 0, 0, 2], [1, 2, 2, 2, 0, 0, 2], [3, 2, 2, 2, 2, 2, 2], [1, 2, 2, 0, 0, 0, 0], [3, 2, 0, 2, 0, 2, 0], [3, 0, 2, 2, 2, 2, 0], [1, 2, 0, 0, 2, 2, 2], [3, 0, 0, 0, 2, 0, 2], [3, 0, 2, 0, 2, 0, 2], [3, 0, 2, 0, 0, 0, 0], [3, 2, 0, 2, 0, 0, 0], [1, 0, 2, 2, 0, 0, 0], [3, 2, 2, 0, 0, 2, 2], [1, 0, 0, 2, 0, 2, 2], [1, 0, 0, 2, 0, 0, 0], [1, 2, 0, 2, 2, 0, 2], [1, 0, 2, 2, 0, 0, 2], [3, 2, 2, 0, 2, 0, 2], [3, 2, 0, 0, 2, 2, 0], [3, 0, 2, 0, 2, 2, 2], [3, 2, 2, 2, 2, 2,0],[3,2,2,0,2,2,2],[3,2,0,0,2,0,2],[3,0,0,2,0,2,2],[1,2,0,2,2,2,2],[1,2,0,0,2,2,0],[3,0,0,2,0,2,0],[1,0,2,2,2,2,2],[1,2,2,2,0,2,0],[1,2,2,2,2,0,2],[1,2,2,0,2,0,0],[3,0,2,2,2,2,2],[3,0,2,0,2,0,0],[3,2,2,0,0,0,2],[1,0,2,0,2,2,2],[3,0,0,2,0,0,0],[1,0,2,0,0,2,0],[3,2,0,0,0,2,2],[1,0,0,0,2,0,0],[3,0,2,0,0,2,2],[3,2,2,0,2,0,0],[3,0,0,0,2,0,0],[3,2,2,2,0,2,2],[3,2,0,0,0,2,0],[1,2,0,0,0,2,0],[1,2,2,2,0,2,2],[1,0,2,0,2,0,0],[3,2,0,2,0,0,2],[3,2,2,0,0,2,0],[1,2,0,2,0,2,2],[1,0,2,0,0,0,2],[1,2,2,2,2,2,0],[3,2,2,2,0,2,0],[1,2,0,0,0,2,2],[1,2,2,0,0,0,2],[3,0,2,2,0,0,2],[3,0,2,0,0,0,2],[3,2,0,2,0,2,2],[1,2,2,0,0,2,0],[1,2,0,2,0,0,2],[1,2,2,0,2,0,2],[3,2,0,2,2,0,2],[1,0,0,2,0,2,0],[1,0,2,0,0,2,2],[3,0,2,0,0,2,0],[3,2,0,2,2,2,2],[3,2,2,2,2,0,2],[1,2,0,0,2,0,2],[1,2,2,0,2,2,2],[3,0,0,2,2,2,2],[3,2,2,2,2,0,0],[1,2,2,2,2,0,0],[3,0,2,2,0,2,0],[1,2,2,0,2,2,0],[3,2,0,0,2,0,0],[3,0,2,2,2,0,2],[1,0,0,2,2,0,0],[1,2,0,2,2,2,0],[3,0,0,2,2,0,2],[3,0,0,2,0,0,2],[1,0,0,2,2,2,2],[3,2,0,2,2,0,0],[1,0,0,2,2,2,0],[3,0,[1, 0, 2, 2, 2, 0, 0], [1, 0, 2, 2, 0, 2, 2], [3, 0, 2, 2, 2, 0, 0], [3, 0, 2, 2, 0, 2, 2], [3, 2, 0, 2, 2, 2, 0], [3, 2, 2, 0, 2, 2, 0], [1, 0, 0, 2, 0, 0, 2], [1, 2, 0, 0, 2, 0, 0], [1, 0, 2, 2, 2, 0, 2], [3, 0, 2, 0, 2, 2, 0], [1, 2, 0, 2, 2, 0, 0], [1, 0, 2, 0, 2, 2, 0], [1, 0, 0, 2, 2, 0, 2], [3, 0, 0, 2, 2, 2, 0], [1, 0, 2, 2, 0, 2, 0].

[0144] As a possible implementation, the W preambles are N sequences (W=N), such as the first preamble is the first sequence in the N sequences, in which case, the first preamble is obtained according to one of the N1 recursive formulas, one of the N2 initial value sequences and one of the N3 cyclic shift values.

[0145] Exemplarily, the W preambles are W Z3 sequences or Z4 sequences. When the W preambles are W Z3 sequences, referring to Table 2, the length L of the current preamble is close to 127 (such as L=121), N CS =3, the value of W is about 84, the length L of the current preamble is close to 255, N CS =3, the value of W is about 170. When the W preambles are W Z4 sequences, referring to Table 2, the length L of the current preamble is 127, N CS =3, the value of W is about 5334, the length L of the current preamble is 255, N CS =3, the value of W is about 21675. In this case, the value of W can be close to 65536 by increasing the length of the preamble, so as to meet the requirement of transmitting 16-bit identification; or the number of the identification of the Internet of Things device can be reduced, which is not limited.

[0146] As another possible implementation, the W preambles are obtained according to the N sequences and the M sequences, the M sequences are obtained according to M1 recursive formulas, a first initial value sequence, and M2 cyclic shift values, M1 is an integer greater than or equal to 1, M2 is an integer greater than 1, and the M2 cyclic shift values are independent of the N2 cyclic shift values. For example, the M2 cyclic shift values can or can not intersect with the N2 cyclic shift values. The M sequences are m sequences. Because the correlation between different m sequences obtained based on the same recursive formula is low, and the correlation between different m sequences obtained based on different recursive formulas is relatively high, M1 can be equal to 1 to ensure the detection performance of the preambles. In the embodiments of the present application, the case of "M1 = 1" is mainly described.

[0147] For example, the W preambles are obtained by scrambling the N sequences using the M sequences. W = N * M. For example, a first preamble of the W preambles is obtained by scrambling a first sequence of the N sequences using a second sequence of the M sequences. The first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], the second sequence is denoted as [c(n)], n = 0, 1, 2,..., L-1, and L represents the length of the first preamble. Then wherein α is a complex constant, x(n+7) = mod(2x(n+4) + 3x(n+1) + x(n), 4), and c(n+7) = mod(c(n+1) + c(n), 2). It can be understood that if the lengths of the first sequence and the second sequence are different, L is equal to the length of the first sequence or the length of the second sequence. For example, the length of the first sequence is less than the length of the second sequence, L is equal to the length of the second sequence, and the first sequence needs to be truncated to a length of L. For another example, the length of the first sequence is greater than the length of the second sequence, L is equal to the length of the first sequence, and the second sequence needs to be cyclically extended to a length of L.

[0148] When the W preambles are obtained by scrambling the N Z3 sequences using the M m sequences, as shown in Table 2, the length L of the preambles is close to 127, N CS = 3, and the value of W is approximately 3528. The length L of the preambles is close to 255, N CS = 3, and the value of W is approximately 14450. In this case, the length of the preambles can be increased to make the value of W close to 65536, so as to meet the requirement of transmitting 16-bit identification. Alternatively, the number of the identification of the Internet of Things device can be reduced, which is not limited.

[0149] When the W preambles are obtained by scrambling the N Z4 sequences using the M m sequences, as shown in Table 2, the length L of the preambles is 127, N CSWhen Z = 3, the value of W is about 224028, the length L of the current preamble is 255, and N CS When Z = 3, the value of W is about 1842375. In this case, the value of W is greater than 65536, so that the requirement of transmitting 16-bit identification can be met, and large-capacity access is achieved.

[0150] (2) The one-to-one correspondence between the plurality of identifications and the plurality of preambles is described.

[0151] Taking the number of identifications as Z (for example, Z = 65536) as an example, the one-to-one correspondence between the Z preambles and the Z identifications can be configured, preconfigured or predefined. The Z preambles can be part or all of the W preambles, that is, Z is less than or equal to W.

[0152] As a possible implementation, a table can be configured, preconfigured or predefined, as shown in Table 3.

[0153] Table 3: Correspondence between Z preambles and Z identifications

[0154] It can be understood that if the number of preambles is greater than 65536, that is, W is greater than 65536, then Z preambles can be selected from the W preambles, and then Z preambles are set to correspond to Z identifications. For example, W is 224028, and 65536 preambles can be selected from the 224028 preambles.

[0155] As another possible implementation, the generation information of the preambles corresponding to each identification can be configured, preconfigured or predefined. For example, the preambles are Z4 sequences, and the generation information of the preambles includes the recurrence formula, the initial value sequence and the cyclic shift value of the Z4 sequence. For example, the preambles are obtained by scrambling the Z4 sequence according to the m sequence, and the generation information of the preambles includes the recurrence formula, the initial value sequence and the cyclic shift value of the m sequence, and the recurrence formula, the initial value sequence and the cyclic shift value of the Z4 sequence. Taking the preambles obtained by scrambling the Z4 sequence according to the m sequence as an example, a table can be configured, preconfigured or predefined, as shown in Table 4.

[0156] Table 4: Correspondence between Z preambles and Z identifications

[0157] Based on Table 4, if the identification of the first terminal device is identification 1, the first terminal device can obtain the m sequence 1 according to the recurrence formula a1, the initial value sequence a1 and the cyclic shift value a1, and obtain the Z4 sequence 1 according to the recurrence formula b1, the initial value sequence b1 and the cyclic shift value b1, and then scramble the Z4 sequence 1 by using the m sequence 1 to obtain the first preamble.

[0158] (3) The implementation of determining whether the terminal device is based on the preamble transmission identifier is described.

[0159] Exemplarily, the terminal device can determine whether it is based on the preamble transmission identifier. For example, the first terminal device determines that it is based on the preamble transmission identifier, and then determines the first preamble corresponding to the identifier of the first terminal device according to the identifier of the first terminal device. For another example, the second terminal device determines that it is not based on the preamble transmission identifier, and then determines the second preamble, which is not associated with the identifier of the second terminal device. Further optionally, considering that the m-sequence has the optimal time synchronization performance in the large frequency offset scenario, the second preamble can be an m-sequence. Wherein, the "based on the preamble transmission identifier" can be replaced by other possible descriptions, such as "reporting the identifier through the preamble", which is not limited in detail.

[0160] Exemplarily, the first preamble and the second preamble can correspond to the same recursive formula of the m-sequence. For example, the first preamble is obtained by scrambling a Z3 sequence by an m-sequence 1 or scrambling a Z4 sequence by an m-sequence 1, and the second sequence is obtained by an m-sequence 2 (such as the second sequence is an m-sequence 2), then the m-sequence 1 and the m-sequence 2 correspond to the same recursive formula (such as the first recursive formula), and the m-sequence 1 and the m-sequence 2 can be the same sequence or different sequences. In this way, since the first preamble and the second preamble are both obtained based on the first recursive formula, the cross-correlation between the first preamble and the second preamble is small, which facilitates reducing the interference between different terminal devices.

[0161] That is, the first preamble is one of Z preambles, assuming that the Z preambles are obtained by scrambling N sequences by M sequences, and the M sequences are obtained by the first recursive formula, a first initial value sequence, and M2 cyclic shift values, then: the second preamble can be one of V preambles, the V preambles are m-sequences, and the V preambles are obtained by the first recursive formula, the first initial value sequence, and V cyclic shift values, such as the second preamble is obtained by the first recursive formula, the first initial value sequence, and the first cyclic shift value in the V cyclic shift values. Wherein, the V cyclic shift values and the M2 cyclic shift values can have an intersection, or can not have an intersection, which is not limited in detail.

[0162] The terminal device whether to base on the preamble transmission identifier can be preconfigured, such as whether to base on the preamble transmission identifier being configured when the terminal device is manufactured. Alternatively, whether the terminal device bases on the preamble transmission identifier can also be configured by the network device, such as the network device sending indication information 1 to the first terminal device before the first terminal device performs uplink access, the indication information 1 being used to instruct the first terminal device to base on the preamble transmission identifier; or the network device sending indication information 2 to the second terminal device before the second terminal device performs uplink access, the indication information 2 being used to instruct the second terminal device not to base on the preamble transmission identifier. The indication information 1 / indication information 2 can be carried in high layer signaling, such as being carried in a master information block (MIB) carried in an SS / PBCH block, or being carried in a MAC CE, without limitation.

[0163] It can be understood that when the indication information 1 / indication information 2 is carried in high layer signaling, if the network device broadcasts the high layer signaling through a system message, in this case, the behaviors of the terminal devices in the same cell are consistent (that is, the terminal devices in the same cell all base on the preamble transmission identifier, or none base on the preamble transmission identifier), and the behaviors of the terminal devices in different cells can be inconsistent, such as the terminal devices in cell 1 all base on the preamble transmission identifier, and the terminal devices in cell 2 all do not base on the preamble transmission identifier. Therefore, through the design in the embodiment of the present application (the first preamble and the second preamble are both obtained based on the first recursive formula), it is convenient to reduce the interference between different terminal devices in different cells.

[0164] S502, the first terminal device sends a first preamble; correspondingly, the network device receives the first preamble from the first terminal device.

[0165] Exemplarily, the first terminal device sends the first preamble based on a single carrier (such as a square wave, which is one of the waveforms in a single carrier), thereby saving the power consumption of the first terminal device, and reducing the complexity of the transmitter and the receiver. In the embodiment of the present application, if the first preamble is obtained based on a Z4 sequence scrambled by an m sequence, or the first preamble is a Z4 sequence, the value set of the first preamble is {1, -1, j, -j}, and the first terminal device sending the first preamble based on the square wave can mean that the first terminal device uses a sine waveform (such as Sin(wt)) to send element 1, uses a sine waveform 2 (such as Sin(-wt)) to send element -1, uses a cosine waveform (such as Cos(wt)) to send element j, and uses a cosine waveform 2 (such as Cos(-wt)) to send element -j.

[0166] S503, the network device performs synchronization with the first terminal device according to the first preamble, and determines the identity of the first terminal device.

[0167] Exemplarily, the implementation that the network device synchronizes with the first terminal device according to the first preamble can refer to the prior art, for example, the network device determines a time advanced (TA) amount according to the first preamble, and the specific implementation is not limited. The network device determines the identity of the first terminal device according to the first preamble, and specifically, the network device determines the identity corresponding to the first preamble according to the one-to-one correspondence between the plurality of identities and the plurality of preambles, and takes the identity corresponding to the first preamble as the identity of the first terminal device.

[0168] By using the above method, since the first preamble sent by the first terminal device corresponds to the identity of the first terminal device, the identity of the terminal device can be transmitted based on the preamble. Further, since N2 and N3 are both greater than 1, that is, the number of initial value sequences and the number of cyclic shift values are both greater than 1, the number of preambles can be expanded by the initial value sequences and the cyclic shift values, so that the preambles are expanded to realize large-capacity access.

[0169] In the scheme provided in the embodiments of the present application, when the identity of the terminal device is transmitted based on the preamble, the preamble can be a Z3 sequence, a Z4 sequence, a Z3 sequence scrambled by an m sequence, or a Z4 sequence scrambled by an m sequence; when the identity of the terminal device is not transmitted based on the preamble, the preamble can be an m sequence. Since the crystal oscillator stability of the Internet of Things device is poor, the frequency offset range is large, and therefore the self / cross-correlation of the preamble in the presence of frequency offset needs to be evaluated.

[0170] (1) The self-correlation of the preamble in the presence of frequency offset is generally evaluated by the second highest peak of the self ambiguity function of the preamble, and the smaller the second highest peak of the self ambiguity function is, the better the synchronization performance of the preamble in the presence of frequency offset is. For example, the expression of the self ambiguity function of the preamble [s(n)] is:

[0171] wherein A(f d ,τ) is the self ambiguity function of [s(n)], f d is a frequency offset value, τ is a time-domain multipath delay, the value range of τ is [0, L-1], and s * (n+τ) is the conjugate of s(n+τ). For example, the main peak of the self ambiguity function of [s(n)] is A(0, 0), and A(f d ,τ)′=A(f d ,τ) / A(0, 0), A(f d ,τ)′ is obtained by normalizing A(f d ,τ). The main peak of the self ambiguity function refers to the maximum value in the self ambiguity function, and the second highest peak of the self ambiguity function refers to the second largest value in the self ambiguity function.

[0172] (2) The cross-correlation of different preambles in the presence of frequency offset is generally evaluated in terms of the main peak of the cross ambiguity function of different preambles, and the smaller the main peak of the cross ambiguity function is, the lower the cross-correlation between different preambles in the presence of frequency offset is, that is, the better the synchronization performance of the preambles in the presence of interference is. The main peak of the cross ambiguity function refers to the maximum value in the cross ambiguity function. For example, for two preambles of a sequence of length L, such as [s1(n)] and [s2(n)], the expression of the cross ambiguity function between [s1(n)] and [s2(n)] is as follows:

[0173] It should be understood that the cross ambiguity function can be further normalized to obtain C'(f d ,τ), C'(f d ,τ) and C(f d ,τ) satisfy the following formula:

[0174] Based on the above descriptions (1) and (2), see Table 5 for an example of simulation values of the secondary peak of the self-ambiguity function (specifically, the normalized secondary peak) / the main peak of the cross ambiguity function (specifically, the normalized main peak) of the preambles in the scheme provided in the embodiments of the present application. The "self-ambiguity function" in the embodiments of the present application can refer to a non-periodic self-ambiguity function, and the "cross ambiguity function" can refer to a non-periodic cross ambiguity function.

[0175] Table 5: Simulation values of the secondary peak of the self-ambiguity function / the main peak of the cross ambiguity function

[0176] In Table 5, the first row indicates that the preambles are m sequences, the secondary peak of the self-ambiguity function of multiple preambles ranges from 0.1047 to 0.1116, and the main peak of the cross ambiguity function of multiple preambles ranges from 0.1058 to 0.1123. For example, the preambles of length 127 (N CS = 3) have 42 in total, and the secondary peak of the self-ambiguity function of the 42 preambles ranges from 0.1047 to 0.1116, and the main peak of the cross ambiguity function of the 42 preambles ranges from 0.1058 to 0.1123.

[0177] The second row indicates that the preambles are Z3 sequences, the secondary peak of the self-ambiguity function of multiple preambles ranges from 0.1458 to 0.1461, and the main peak of the cross ambiguity function of multiple preambles ranges from 0.1303 to 0.1642.

[0178] The 3rd row indicates that the preamble is a Z3 sequence scrambled by an m sequence, the value range of the secondary peak of the self-correlation function of the plurality of preambles is 0.1704-0.1849, and the value range of the main peak of the cross-correlation function of the plurality of preambles is 0.1853-0.2766.

[0179] Similarly, the 6th row indicates that the preamble associated with the identifier is a Z4 sequence, the preamble not associated with the identifier is an m sequence, the value range of the secondary peak of the self-correlation function of the plurality of preambles is 0.1047-0.18, and the value range of the main peak of the cross-correlation function of the plurality of preambles is 0.105-0.2997. For example, there are x1 preambles associated with the identifier, and there are x2 preambles not associated with the identifier, the value range of the secondary peak of the self-correlation function of the (x1+x2) preambles is 0.1047-0.18, and the value range of the main peak of the cross-correlation function of the (x1+x2) preambles is 0.105-0.2997.

[0180] The 7th row indicates that the preamble associated with the identifier is a Z4 sequence scrambled by an m sequence 1, the preamble not associated with the identifier is an m sequence 2 (the m sequence 1 and the m sequence 2 correspond to the same recursive formula), the value range of the secondary peak of the self-correlation function of the plurality of preambles is 0.1047-0.1859, and the value range of the main peak of the cross-correlation function of the plurality of preambles is 0.1051-0.1961.

[0181] The 8th row indicates that the preamble associated with the identifier is a Z4 sequence scrambled by an m sequence 1, the preamble not associated with the identifier is an m sequence 2 (the m sequence 1 and the m sequence 2 correspond to different recursive formulas), the value range of the secondary peak of the self-correlation function of the plurality of preambles is 0.1047-0.1859, and the value range of the main peak of the cross-correlation function of the plurality of preambles is 0.1051-0.3045.

[0182] As can be seen from Table 5, when the identifier of the terminal device is transmitted based on the preamble, the preamble is a Z4 sequence scrambled by an m sequence 1, when the identifier of the terminal device is not transmitted based on the preamble, the preamble is an m sequence 2, and the m sequence 1 and the m sequence 2 correspond to the same recursive formula, the value of the secondary peak of the self-correlation function / cross-correlation function of the main peak of the plurality of preambles is low (the performance approaches the m sequence), that is, the self / cross-correlation is low when there is a frequency offset, thereby making the anti-frequency offset ability of the preambles stronger.

[0183] For the above embodiments, it can be understood that:

[0184] (1) In the embodiments of the present application, the terms and / or descriptions in different examples or implementation manners are consistent and can be referred to each other if there is no special description and logical conflict, and the technical features in different examples or implementation manners can be combined to form new embodiments according to their inherent logical relationship. In addition, different implementation manners or different examples can refer to or refer to each other.

[0185] (2) The various numerical numbers involved in the present application are only for the convenience of differentiation and do not limit the scope of the present application. The step numbers of the above various flowcharts are only an example of the execution flow and do not constitute a limitation on the execution order of the steps, that is, the size of each step number does not mean the execution order, and the execution order of each step should be determined according to its function and inherent logic. In addition, the steps shown in each flowchart are not all the steps that must be executed, and some steps can be added or deleted based on each flowchart according to actual needs.

[0186] The above mainly introduces the scheme provided by the embodiments of the present application from the perspective of the interaction between the first communication device and the second communication device. It can be understood that in order to realize the above functions, the first communication device and the second communication device can include corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should easily realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in the present application can be realized in the form of hardware or a combination of hardware and computer software. Whether a certain function is realized in the form of hardware or computer software driven hardware depends on the specific application of the technical solution and the design constraints. Professional technicians can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0187] The embodiments of the present application can divide the functional units of the first communication device and the second communication device according to the above method examples, for example, each functional unit can be divided according to each function, or two or more functions can be integrated into one unit. The integrated unit can be realized in the form of hardware or software functional unit.

[0188] In the case of using integrated units, FIG6 shows a possible exemplary block diagram of the device involved in the embodiments of this application. As shown in FIG6, the device 600 may include a processing unit 602 and a communication unit 603. The processing unit 602 is used to control and manage the operation of the device 600. The communication unit 603 is used to support communication between the device 600 and other devices. Optionally, the communication unit 603 is also called a transceiver unit, and may include a receiving unit and / or a sending unit, respectively used to perform receiving and sending operations. The device 600 may also include a storage unit 601 for storing the program code and / or data of the device 600.

[0189] (1) The device 600 can be the first communication device in the above embodiments. The processing unit 602 can support the device 600 in performing the actions of the first communication device in the above method embodiments. Alternatively, the processing unit 602 mainly performs the internal actions of the first communication device in the method embodiments, and the communication unit 603 can support communication between the device 600 and other devices.

[0190] For example, in one embodiment, the processing unit 602 is used to: determine a first preamble corresponding to the identifier of the first terminal device; the communication unit 603 is used to: send the first preamble; wherein the first preamble is obtained based on a first sequence, the first sequence being one of N sequences, the N sequences being obtained based on N1 recursive formulas, N2 initial value sequences and N3 cyclic shift values, N1 being an integer greater than or equal to 1, and N2 and N3 being integers greater than 1.

[0191] In one possible design, the communication unit 603 is specifically used to: transmit the first preamble based on a square wave.

[0192] In one possible design, the processing unit 602 is specifically used to: determine the first preamble corresponding to the identifier based on the identifier of the first terminal device and the one-to-one correspondence between multiple identifiers and multiple preambles.

[0193] In one possible design, the first sequence is a Z4 sequence.

[0194] In one possible design, the first preamble is obtained based on a first sequence, including: the first preamble is obtained based on a first sequence and a second sequence, or the first preamble is the first sequence; the second sequence is one of M sequences, which are obtained based on M1 recursive formulas, a first initial value sequence and M2 cyclic shift values, where M1 is an integer greater than or equal to 1 and M2 is an integer greater than 1.

[0195] In one possible design, the second sequence is an m-sequence.

[0196] In a possible design, the first preamble is obtained by scrambling the first sequence with the second sequence, including: the first preamble is obtained by scrambling the first sequence with the second sequence.

[0197] In a possible design, the first preamble is obtained by scrambling the first sequence with the second sequence, including: the first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], and the second sequence is denoted as [c(n)], where n=0, 1, 2, …, L-1. where α is a complex constant.

[0198] In a possible design, the processing unit 602 is further configured to determine the identity based on the preamble transmission.

[0199] In a possible design, the communication unit 603 is further configured to receive indication information from the network device, where the indication information is used to instruct the first terminal device to transmit the identity based on the preamble.

[0200] (2) The apparatus 600 can be the second communication apparatus in the above embodiments. The processing unit 602 can enable the apparatus 600 to perform the actions of the second communication apparatus in the above method embodiments. Alternatively, the processing unit 602 mainly performs the internal actions of the second communication apparatus in the method embodiments, and the communication unit 603 can enable the apparatus 600 to communicate with other devices.

[0201] For example, in an embodiment, the communication unit 603 is configured to receive a first preamble from a first terminal device, and the processing unit 602 is configured to synchronize with the first terminal device based on the first preamble, and determine an identity of the first terminal device, where the first preamble is obtained based on a first sequence, and the first sequence is one of N sequences, and the N sequences are obtained based on N1 recursive formulas, N2 initial value sequences and N3 cyclic shift values, N1 is an integer greater than or equal to 1, and N2 and N3 are integers greater than 1.

[0202] In a possible design, the processing unit 602 is specifically configured to determine the identity of the first terminal device corresponding to the first preamble based on the one-to-one correspondence between the first preamble and the multiple identities and the multiple preambles.

[0203] In a possible design, the first sequence is a Z4 sequence.

[0204] In a possible design, the first preamble is obtained according to a first sequence, including: the first preamble is obtained according to a first sequence and a second sequence, or the first preamble is the first sequence; the second sequence is one of M sequences, and the M sequences are obtained according to M1 recursive formulas, a first initial value sequence, and M2 cyclic shift values, where M1 is an integer greater than or equal to 1, and M2 is an integer greater than 1.

[0205] In a possible design, M1=1, and the M1 recursive formulas include a first recursive formula; the communication unit 603 further receives a second preamble from a second terminal device, and synchronizes with the second terminal device according to the second preamble, where the second preamble is obtained according to the first recursive formula, the first initial value sequence, and a first cyclic shift value.

[0206] In a possible design, the second sequence is an m sequence.

[0207] In a possible design, the first cyclic shift value is different from the M2 cyclic shift values, or the first cyclic shift value is one of the M2 cyclic shift values.

[0208] In a possible design, the first preamble is obtained according to a first sequence and a second sequence, including: the first preamble is obtained by scrambling the first sequence with the second sequence.

[0209] In a possible design, the first preamble is obtained by scrambling the first sequence with the second sequence, including: the first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], and the second sequence is denoted as [c(n)], where n=0, 1, 2,..., L-1. where α is a complex constant.

[0210] In a possible design, the communication unit 603 further sends indication information to the first terminal device, where the indication information is used to instruct the first terminal device to transmit the identity based on a preamble.

[0211] It should be understood that the division of units in the above apparatus is only a logical functional division, and in actual implementation, all or part of the units can be integrated into one physical entity, or can be physically separated. The units in the apparatus can all be implemented in the form of software invoked by a processing element; or all be implemented in the form of hardware; or part of the units are implemented in the form of software invoked by a processing element, and part of the units are implemented in the form of hardware. For example, each unit can be a separately established processing element, or can be integrated in a chip of the apparatus, in addition, the unit can also be stored in the form of a program in a memory, and the function of the unit is invoked and executed by a processing element of the apparatus. In addition, all or part of the units can be integrated together, or can be independently implemented. The processing element described herein can be a processor, which can be an integrated circuit with a signal processing capability. In the implementation process, each operation of the above method or each unit can be implemented by an integrated logic circuit of hardware in the processing element, or in the form of software invoked by the processing element.

[0212] In one example, the units in any of the above apparatuses can be one or more integrated circuits configured to implement the above methods, for example, one or more application specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms. For another example, when the units in the apparatus can be implemented in the form of a program invoked by a processing element, the processing element can be a processor, such as a general purpose central processing unit (CPU), or other processor capable of invoking programs. For another example, the units can be integrated together to implement in the form of SoC.

[0213] The above receiving unit is an interface circuit of the apparatus for receiving signals from other apparatuses. For example, when the apparatus is implemented in the form of a chip, the receiving unit is an interface circuit of the chip for receiving signals from other chips or apparatuses. The above transmitting unit is an interface circuit of the apparatus for transmitting signals to other apparatuses. For example, when the apparatus is implemented in the form of a chip, the transmitting unit is an interface circuit of the chip for transmitting signals to other chips or apparatuses.

[0214] Based on the same technical concept, the embodiments of the present application further provide a communication device for implementing the functions of the first communication device or the second communication device in the above embodiments. As shown in FIG. 7, the device can be a communication equipment or a chip in the communication equipment. The device comprises a processor 701 and a communication interface 702, and optionally further comprises a memory 703. FIG. 7 only shows the main components of the communication device. In addition to the processor 701 and the communication interface 702, the communication device can further comprise the memory 703 and an input / output device (not shown in the figure).

[0215] The processor 701 is configured to execute the program codes stored in the memory 703, and specifically configured to execute the actions of the processing unit 602. Details are not described herein again. The communication interface 702 is specifically configured to execute the actions of the communication unit 603. Details are not described herein again.

[0216] The processor 701 can be a CPU, or a digital processing unit, etc. The processor 701 can be configured to process communication protocols and communication data, control the whole communication device, execute software programs, process data of the software programs, such as but not limited to, baseband related processing. The communication interface 702 can be configured to transceive signals, such as but not limited to, radio frequency transceiving. The above devices can be respectively arranged on independent chips, or at least partially or entirely arranged on the same chip. For example, the processor 701 can be further divided into an analog baseband processor and a digital baseband processor. The analog baseband processor can be integrated on the same chip as the transceiver, and the digital baseband processor can be arranged on an independent chip. With the continuous development of integrated circuit technology, more and more devices can be integrated on the same chip, for example, the digital baseband processor can be integrated on the same chip as various application processors (such as but not limited to, graphic processors, multimedia processors, etc.). Such a chip can be called a system on chip. Whether to arrange the devices independently on different chips or to integrate them on one or more chips often depends on the specific needs of product design. The embodiments of the present application do not limit the specific implementation forms of the above devices.

[0217] The communication interface 702 can be a transceiver, an interface circuit such as a transceiving circuit, a transceiving chip, etc. Optionally, the communication interface 702 can comprise a radio frequency circuit and an antenna. The radio frequency circuit is mainly configured to convert baseband signals and radio frequency signals and process the radio frequency signals. The antenna is mainly configured to transceive radio frequency signals in the form of electromagnetic waves. The input / output device, such as a touch screen, a display screen, a keyboard, etc. is mainly configured to receive user input data and output data to the user.

[0218] The memory 703 is configured to store programs executed by the processor 701. The memory 703 can be a non-volatile memory such as a hard disk drive (HDD) or a solid-state drive (SSD), and can also be a volatile memory such as a random-access memory (RAM). The memory 703 can be any other medium capable of carrying or storing desired program codes in the form of instructions or data structures and capable of being accessed by a computer, but is not limited to this.

[0219] When the communication apparatus is powered on, the processor 701 can read a software program in the memory 703, interpret and execute instructions of the software program, and process data of the software program. When data needs to be transmitted wirelessly, the processor 701 performs baseband processing on the data to be transmitted, and outputs a baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal, and transmits a radio frequency signal in the form of an electromagnetic wave through an antenna. When data is transmitted to the communication apparatus, the radio frequency circuit receives a radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 701. The processor 701 converts the baseband signal into data and processes the data.

[0220] In another implementation, the radio frequency circuit and the antenna can be arranged independently of the processor that performs baseband processing, for example, in a distributed scenario, the radio frequency circuit and the antenna can be arranged remotely from the communication apparatus.

[0221] The specific connection medium between the communication interface 702, the processor 701, and the memory 703 is not limited in the embodiments of the present application. In FIG. 7, the memory 703, the processor 701, and the communication interface 702 are connected through a bus 704, which is represented by a thick line in FIG. 7. The connection mode between other components is only schematically illustrated, and is not limited to this. The bus can be divided into an address bus, a data bus, a control bus, and the like. For convenience of representation, only one thick line is used in FIG. 7, but it does not mean that there is only one bus or only one type of bus.

[0222] Optionally, the communication apparatus can be an independent device or can be part of a larger device. For example, the communication apparatus can be:

[0223] (1) an independent integrated circuit (IC), or a chip, or a chip system or subsystem;

[0224] (2) a set of one or more ICs, and optionally, the set of ICs can also include a storage component for storing data and instructions;

[0225] (3) Application specific integrated circuit (ASIC), such as a modem;

[0226] (4) A module that can be embedded within other devices;

[0227] (5) A receiver, a smart terminal, a wireless device, a handset, a mobile unit, a car device, a cloud device, an artificial intelligence device, and the like;

[0228] (6) Other, and the like.

[0229] In the embodiments of the present application, "multiple" can mean two or more. In view of this, "multiple" in the embodiments of the present application can also be understood as "at least two". "At least one" can be understood as one or more, for example, as one, two or more. For example, "including at least one" means including one, two or more, for example, including at least one of A, B and C, and the included can be A, B, C, A and B, A and C, B and C, or A, B and C. "And / or" describes the association relationship of the associated objects, and specifically can exist in three relationships, for example, A and / or B can represent: A exists alone, A and B exist together, and B exists alone. In addition, the character " / ", if not specially stated, generally represents that the associated objects before and after are in an "or" relationship.

[0230] In addition, the terms "system" and "network" in the embodiments of the present application can be used interchangeably, and "according to" and "based on" can be used interchangeably. The ordinal numbers "first", "second" and the like mentioned in the embodiments of the present application are generally used to distinguish different objects, and are not used to limit the order, time sequence, priority or importance of multiple objects. For example, the first communication device and the second communication device in the embodiments of the present application are used to distinguish two communication devices, and do not limit the priority or importance of the two communication devices.

[0231] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0232] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks or in conjunction with the flowchart blocks. These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks.

[0233] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks or in conjunction with the flowchart blocks. These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks.

[0234] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks or in conjunction with the flowchart blocks. These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks.

Claims

1. A communication method characterized by comprising: The method comprises: determining a first preamble corresponding to the identity of the first terminal device according to the identity of the first terminal device; sending the first preamble; wherein the first preamble is obtained according to a first sequence, the first sequence is one of N sequences, the N sequences are obtained according to N1 recursive formulas, N2 initial value sequences and N3 cyclic shift values, N1 is an integer greater than or equal to 1, and N2 and N3 are integers greater than 1.

2. The method of claim 1, wherein, The sending of the first preamble comprises: sending the first preamble based on a square wave.

3. The method according to claim 1 or 2, characterized in that, The determining of the first preamble corresponding to the identity of the first terminal device comprises: determining the first preamble corresponding to the identity of the first terminal device according to a one-to-one correspondence between a plurality of identities and a plurality of preambles.

4. The method according to any one of claims 1 to 3, characterized in that, The first sequence is a Z4 sequence.

5. The method according to any one of claims 1 to 4, characterized in that, The first preamble is obtained according to a first sequence and a second sequence, or the first preamble is the first sequence. The second sequence is one of M sequences, the M sequences are obtained according to M1 recursive formulas, a first initial value sequence and M2 cyclic shift values, M1 is an integer greater than or equal to 1, and M2 is an integer greater than 1. The second sequence is an m sequence.

6. The method of claim 5, wherein, The first preamble is obtained according to a first sequence and a second sequence, comprising:

7. The method according to claim 5 or 6, characterized in that, The first preamble is obtained by scrambling the first sequence with the second sequence. The first preamble is obtained by scrambling the first sequence with the second sequence, comprising:

8. The method of claim 7, wherein, The first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], and the second sequence is denoted as [c(n)], n = 0, 1, 2, …, L-1. Wherein, α is a complex constant. s(n) = a e jx(n)π / 2 • c(n) The method further comprises:

9. The method according to any one of claims 1 to 8, characterized in that, determining to transmit the identity based on the preamble. The determination to transmit the identity based on the preamble comprises:

10. The method of claim 9, wherein, receiving indication information from the network device, the indication information being used to indicate that the first terminal device transmits the identity based on the preamble. The length of the N sequences is 127, and the N2 initial value sequences [x(0), x(1), x(2), x(3), x(4), x(5), x(6)] comprise at least one of the following:

11. The method according to any one of claims 1 to 10, characterized in that, The method comprises: [1,0,0,0,0,0,0],[3,0,0,0,0,0,0],[1,0,0,0,2,2,2],[3,2,0,0,0,0,0],[1,2,2,2,0,0,0],[1,0,0,0,0,0,2],[3,0,0,0,0,0,2],[3,2,2,2,0,0,0],[1,2,0,0,0,0,0],[3,0,0,0,2,2,2],[1,2,0,2,0,2,0],[3,2,2,0,0,0,0],[1,2,2,2,2,2,2],[1,2,2,0,0,2,2],[3,0,2,2,0,0,0],[1,2,0,2,0,0,0],[1,0,2,0,0,0,0],[1,0,2,0,2,0,2],[1,0,0,0,2,0,2],[3,2,0,0,2,2,2],[1,0,2,2,2,2,0],[1,0,0,0,0,2,0],[3,0,0,0,0,2,0],[3,2,2,2,0,0,2],[3,2,0,0,0,0,2],[3,0,0,0,2,2,0],[1,0,0,0,0,2,2],[3,0,0,0,0,2,2],[1,0,0,0,2,2,0],[1,2,0,0,0,0,2],[1,2,2,2,0,0,2],[3,2,2,2,2,2,2],[1,2,2,0,0,0,0],[3,2,0,2,0,2,0],[3,0,2,2,2,2,0],[1,2,0,0,2,2,2],[3,0,0,0,2,0,2],[3,0,2,0,2,0,2],[3,0,2,0,0,0,0],[3,2,0,2,0,0,0],[1,0,2,2,0,0,0],[3,2,2,0,0,2,2],[1,0,0,2,0,2,2],[1,0,0,2,0,0,0],[1,2,0,2,2,0,2],[1,0,2,2,0,0,2],[3,2,2,0,2,0,2],[3,2,0,0,2,2,0],[3,0,2,0,2,2,2],[3,2,2,2,2,2,0],[3,2,2,0,2,2,2],[3,2,0,0,2,0,2],[3,0,0,2,0,2,2],[1,2,0,2,2,2,2],[1,2,0,0,2,2,0],[3,0,0,2,0,2,0],[1,0,2,2,2,2,2],[1,2,2,2,0,2,0],[1,2,2,2,2,0,2],[1,2,2,0,2,0,0],[3,0,2,2,2,2,2],[3,0,2,0,2,0,0],[3,2,2,0,0,0,2],[1,0,2,0,2,2,2],[3,0,0,2,0,0,0],[1,0,2,0,0,2,0],[3,2,0,0,0,2,2],[1,0,0,0,2,0,0],[3,0,2,0,0,2,2],[3,2,2,0,2,0,0],[3,0,0,0,2,0,0],[3,2,2,2,0,2,2],[3,2,0,0,0,2,0],[1,2,0,0,0,2,0],[1,2,2,2,0,2,2],[1,0,2,0,2,0,0],[3,2,0,2,0,0,2],[3,2,2,0,0,2,0],[1,2,0,2,0,2,2],[1,0,2,0,0,0,2],[1,2,2,2,2,2,0],[3,2,2,2,0,2,0],[1,2,0,0,0,2,2],[1,2,2,0,0,0,2],[3,0,2,2,0,0,2],[3,0,2,0,0,0,2],[3,2,0,2,0,2,2],[1,2,2,0,0,2,0],[1,2,0,2,0,0,2],[1,2,2,0,2,0,2],[3,2,0,2,2,0,2],[1,0,0,2,0,2,0],[1,0,2,0,0,2,2],[3,0,2,0,0,2,0],[3,2,0,2,2,2,2],[3,2,2,2,2,0,2],[1,2,0,0,2,0,2],[1,2,2,0,2,2,2],[3,0,0,2,2,2,2],[3,2,2,2,2,0,0],[1,2,2,2,2,0,0],[3,0,2,2,0,2,0],[1,2,2,0,2,2,0],[3,2,0,0,2,0,0],[3,0,2,2,2,0,2],[1,0,0,2,2,0,0],[1,2,0,2,2,2,0],[3,0,0,2,2,0,2],[3,0,0,2,0,0,2],[1,0,0,2,2,2,2],[3,2,0,2,2,0,0],[1,0,0,2,2,2,0],[3,0,0,2,2,0,0],[1,0,2,2,2,0,0],[1,0,2,2,0,2,2],[3,0,2,2,2,0,0],[3,0,2,2,0,2,2],[3,2,0,2,2,2,0],[3,2,2,0,2,2,0],[1,0,0,2,0,0,2],[1,2,0,0,2,0,0],[1,0,2,2,2,0,2],[3,0,2,0,2,2,0],[1,2,0,2,2,0,0],[1,0,2,0,2,2,0],[1,0,0,2,2,0,2],[3,0,0,2,2,2,0],[1,0,2,2,0,2,0]。 12. A communication method characterized by comprising: receiving a first preamble from a first terminal device; synchronizing with the first terminal device according to the first preamble, and determining the identity of the first terminal device; wherein the first preamble is obtained according to a first sequence, the first sequence is one of N sequences, the N sequences are obtained according to N1 recursive formulas, N2 initial value sequences and N3 cyclic shift values, N1 is an integer greater than or equal to 1, and N2 and N3 are integers greater than 1. The determination of the identity of the first terminal device according to the first preamble comprises:

13. The method of claim 12, wherein, determining the identity of the first terminal device corresponding to the first preamble according to a one-to-one correspondence between a plurality of identities and a plurality of preambles. The first sequence is a Z4 sequence.

14. The method according to claim 12 or 13, characterized in that, ​ 15. The method according to any one of claims 12 to 14, characterized in that, The first preamble is obtained according to a first sequence, comprising: The first preamble is obtained according to a first sequence and a second sequence, or the first preamble is the first sequence. The second sequence is one of M sequences, and the M sequences are obtained according to M1 recursive formulas, a first initial value sequence and M2 cyclic shift values, M1 is an integer greater than or equal to 1, and M2 is an integer greater than 1.

16. The method of claim 15, wherein, The second sequence is an m sequence.

17. The method according to claim 15 or 16, characterized in that, M1 is 1, and the M1 recursive formulas include a first recursive formula. The method further comprises: receiving a second preamble from a second terminal device; synchronizing with the second terminal device according to the second preamble; The second preamble is obtained according to the first recursive formula, the first initial value sequence and a first cyclic shift value.

18. The method of any one of claims 15-17, wherein, The first preamble is obtained according to a first sequence and a second sequence, comprising: The first preamble is obtained by scrambling the first sequence with the second sequence.

19. The method of claim 18, wherein, The first preamble is obtained by scrambling the first sequence with the second sequence, comprising: the first preamble is denoted as [s(n)], the first sequence is denoted as [x(n)], and the second sequence is denoted as [c(n)], n = 0, 1, 2,..., L-1; s(n) = αe jx(n)π / 2 ·c(n), wherein α is a complex constant.

20. The method of any one of claims 12-19, wherein, The method further comprises: sending indication information to the first terminal device, the indication information being used to instruct the first terminal device to transmit the identity based on a preamble.

21. The method according to any one of claims 12 to 20, characterized in that, The length of the N sequences is 127, and the N2 initial value sequences [x(0), x(1), x(2), x(3), x(4), x(5), x(6)] include at least one of the following: [1,0,0,0,0,0,0],[3,0,0,0,0,0,0],[1,0,0,0,2,2,2],[3,2,0,0,0,0,0],[1,2,2,2,0,0,0],[1,0,0,0,0,0,2],[3,0,0,0,0,0,2],[3,2,2,2,0,0,0],[1,2,0,0,0,0,0],[3,0,0,0,2,2,2],[1,2,0,2,0,2,0],[3,2,2,0,0,0,0],[1,2,2,2,2,2,2],[1,2,2,0,0,2,2],[3,0,2,2,0,0,0],[1,2,0,2,0,0,0],[1,0,2,0,0,0,0],[1,0,2,0,2,0,2],[1,0,0,0,2,0,2],[3,2,0,0,2,2,2],[1,0,2,2,2,2,0],[1,0,0,0,0,2,0],[3,0,0,0,0,2,0],[3,2,2,2,0,0,2],[3,2,0,0,0,0,2],[3,0,0,0,2,2,0],[1,0,0,0,0,2,2],[3,0,0,0,0,2,2],[1,0,0,0,2,2,0],[1,2,0,0,0,0,2],[1,2,2,2,0,0,2],[3,2,2,2,2,2,2],[1,2,2,0,0,0,0],[3,2,0,2,0,2,0],[3,0,2,2,2,2,0],[1,2,0,0,2,2,2],[3,0,0,0,2,0,2],[3,0,2,0,2,0,2],[3,0,2,0,0,0,0],[3,2,0,2,0,0,0],[1,0,2,2,0,0,0],[3,2,2,0,0,2,2],[1,0,0,2,0,2,2],[1,0,0,2,0,0,0],[1,2,0,2,2,0,2],[1,0,2,2,0,0,2],[3,2,2,0,2,0,2],[3,2,0,0,2,2,0],[3,0,2,0,2,2,2],[3,2,2,2,2,2,0],[3,2,2,0,2,2,2],[3,2,0,0,2,0,2],[3,0,0,2,0,2,2],[1,2,0,2,2,2,2],[1,2,0,0,2,2,0],[3,0,0,2,0,2,0],[1,0,2,2,2,2,2],[1,2,2,2,0,2,0],[1,2,2,2,2,0,2],[1,2,2,0,2,0,0],[3,0,2,2,2,2,2],[3,0,2,0,2,0,0],[3,2,2,0,0,0,2],[1,0,2,0,2,2,2],[3,0,0,2,0,0,0],[1,0,2,0,0,2,0],[3,2,0,0,0,2,2],[1,0,0,0,2,0,0],[3,0,2,0,0,2,2],[3,2,2,0,2,0,0],[3,0,0,0,2,0,0],[3,2,2,2,0,2,2],[3,2,0,0,0,2,0],[1,2,0,0,0,2,0],[1,2,2,2,0,2,2],[1,0,2,0,2,0,0],[3,2,0,2,0,0,2],[3,2,2,0,0,2,0],[1,2,0,2,0,2,2],[1,0,2,0,0,0,2],[1,2,2,2,2,2,0],[3,2,2,2,0,2,0],[1,2,0,0,0,2,2],[1,2,2,0,0,0,2],[3,0,2,2,0,0,2],[3,0,2,0,0,0,2],[3,2,0,2,0,2,2],[1,2,2,0,0,2,0],[1,2,0,2,0,0,2],[1,2,2,0,2,0,2],[3,2,0,2,2,0,2],[1,0,0,2,0,2,0],[1,0,2,0,0,2,2],[3,0,2,0,0,2,0],[3,2,0,2,2,2,2],[3,2,2,2,2,0,2],[1,2,0,0,2,0,2],[1,2,2,0,2,2,2],[3,0,0,2,2,2,2],[3,2,2,2,2,0,0],[1,2,2,2,2,0,0],[3,0,2,2,0,2,0],[1,2,2,0,2,2,0],[3,2,0,0,2,0,0],[3,0,2,2,2,0,2],[1,0,0,2,2,0,0],[1,2,0,2,2,2,0],[3,0,0,2,2,0,2],[3,0,0,2,0,0,2],[1,0,0,2,2,2,2],[3,2,0,2,2,0,0],[1,0,0,2,2,2,0],[3,0,0,2,2,0,0],[1,0,2,2,2,0,0],[1,0,2,2,0,2,2],[3,0,2,2,2,0,0],[3,0,2,2,0,2,2],[3,2,0,2,2,2,0],[3,2,2,0,2,2,0],[1,0,0,2,0,0,2],[1,2,0,0,2,0,0],[1,0,2,2,2,0,2],[3,0,2,0,2,2,0],[1,2,0,2,2,0,0],[1,0,2,0,2,2,0],[1,0,0,2,2,0,2],[3,0,0,2,2,2,0],[1,0,2,2,0,2,0]。 22. A communications device, characterized by The unit for executing the method of any one of claims 1 to 21.

23. A communications device, characterized by The processor is coupled with the memory, and the memory stores a computer program; the processor is used to call part or all of the computer program in the memory, so that the method of any one of claims 1 to 21 is executed.

24. A communication system, characterized by The communication system comprises a first communication device and a second communication device, the first communication device is used to execute the method of any one of claims 1 to 11, and the second communication device is used to execute the method of any one of claims 12 to 21.

25. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, and when part or all of the computer program is executed by a computer, the method of any one of claims 1 to 21 is executed.

26. A computer program product, characterised in that, When the computer reads and executes the computer program product, the method of any one of claims 1 to 21 is executed.

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