Information transmission methods, first communication node, second communication node and storage medium

Abstract

Disclosed in the present application are information transmission methods, a first communication node, a second communication node and a storage medium. An information transmission method comprises: acquiring first preamble information and first data, the first preamble information comprising a start-indicator part and a clock-acquisition part, and the time domain resource position of the first data being after that of the first preamble information; parsing the first data on the basis of the first preamble information; and, in response to the first data, transmitting a first sequence and second data, the first sequence being determined according a target parameter.

Description

Information transmission method, first communication node, second communication node and storage medium TECHNICAL FIELD The present application relates to the technical field of communication, for example, to an information transmission method, a first communication node, a second communication node and a storage medium. BACKGROUND Internet of Things (IoT) is a network that connects objects with the Internet through various sensors or chips and exchanges data and communicates according to certain rules. Internet of Things devices refer to physical devices connected through the Internet or a 5th-Generation Mobile Communication Technology (5G) network or a 6th-Generation Mobile Communication Technology (6G) network and capable of data exchange and communication. Based on the low complexity design requirement of Internet of Things devices, some Internet of Things devices do not have energy storage devices, and therefore need to obtain energy from the surrounding environment (for example, the high level of downlink signaling). The uplink signal is transmitted by backscattering. The synchronization between the Internet of Things device and the base station is poor. SUMMARY The present application provides an information transmission method, a first communication node, a second communication node and a storage medium. In a first aspect, the present application provides a data transmission method, comprising: obtaining first preamble information and first data, the first preamble information comprising a start indication part and a clock acquisition part, and the time domain resource position of the first data being after the first preamble information; analyzing the first data based on the first preamble information; in response to the first data, transmitting a first sequence and second data, the first sequence being determined according to a target parameter. In a second aspect, the present application provides a data transmission method, comprising: transmitting first preamble information and first data, the first preamble information comprising a start indication part and a clock acquisition part, and the time domain resource position of the first data being after the first preamble information, and the first data being analyzed based on the first preamble information; obtaining a first sequence and second data, the first sequence being determined according to a target parameter, and the first sequence and the second data being contents transmitted in response to the first data. In a third aspect, the present application provides a first communication node, comprising: one or more processors; a memory device configured to store one or more programs; The one or more programs, when executed by the one or more processors, enable the one or more processors to implement a data transmission method according to embodiments of the present disclosure. In a fourth aspect, a second communication node is provided, comprising: one or more processors; a memory device configured to store one or more programs; The one or more programs, when executed by the one or more processors, enable the one or more processors to implement a data transmission method according to embodiments of the present disclosure. In a fifth aspect, a storage medium is provided, which stores a computer program. The computer program, when executed by a processor of a first communication node, implements the information transmission method according to embodiments of the present disclosure, or the computer program, when executed by a processor of a second communication node, implements the information transmission method according to embodiments of the present disclosure. Further description is provided in the following description of drawings, detailed description and claims regarding the above embodiments and other aspects of the present disclosure and implementation thereof. SUMMARY FIG. 1 is a flow diagram of a data transmission method according to an embodiment of the present disclosure; FIG. 2 is a flow diagram of another data transmission method according to an embodiment of the present disclosure; FIG. 3 is a diagram of a start indication part according to an embodiment of the present disclosure; FIG. 4 is a diagram of another start indication part according to an embodiment of the present disclosure; FIG. 5 is a diagram of another start indication part according to an embodiment of the present disclosure; FIG. 6 is a diagram of another start indication part according to an embodiment of the present disclosure; FIG. 7 is a diagram of second preamble information according to an embodiment of the present disclosure; FIG. 8 is a diagram of another second preamble information according to an embodiment of the present disclosure; FIG. 9 is a structural diagram of a data transmission apparatus according to an embodiment of the present disclosure; FIG. 10 is a structural diagram of another data transmission apparatus according to an embodiment of the present disclosure; FIG. 11 is a structural diagram of a first communication node according to an embodiment of the present disclosure; FIG. 12 is a structural diagram of a second communication node according to an embodiment of the present disclosure. DETAILED DESCRIPTION In order to make the objects, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other arbitrarily without conflict. The steps shown in the flowchart of the drawings can be executed in a computer system such as a set of computer-executable instructions. Moreover, although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown. The terms "first", "second", and the like in the present application are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. Internet of Things, for example, Ambient Internet of Things (Ambient-IoT, A-IoT), A-IoT is a concept combining environmental perception and Internet of Things (IoT) technology. A-IoT devices mainly use Internet of Things devices that collect energy from radio waves or other available energy sources and are driven by them. Wireless communication is of great concern. Internet of Things connects multiple things to each other to improve production efficiency or increase life comfort. Since Internet of Things applications need to deploy hundreds of millions of devices, Internet of Things devices need to be small in size, low in complexity, and low in power consumption. Internet of Things devices can refer to physical devices that can connect to the Internet of Things and interact with other devices or systems. Based on the low-complexity design requirements of Internet of Things devices, some Internet of Things devices do not have energy storage devices, and the device needs to obtain energy from the surrounding environment (for example, the high level of downlink signaling). The uplink signal is transmitted by backscatter (also known as backscatter). The synchronization of Internet of Things devices with the base station is poor, but the Internet of Things scenario also needs to meet certain coverage requirements, so the data transmission needs to be determined at that time. Internet of Things devices can be divided into most of them are passive (without batteries), and the content considered in the signaling design and transmission is different from active terminals such as mobile phones. For passive Internet of Things devices, the reader (or excitation source) needs to continuously send high-level power to the Internet of Things device or activate / charge the Internet of Things device. After the Internet of Things device is activated, it receives the downlink signaling sent by the reader and returns the uplink signaling to the reader through backscatter. The reader can be a base station or a terminal device such as a mobile phone. In the study of Ambient-IoT, the A-IoT device is considered as a tag, etc. The device type is divided into 3 categories. The first type, i.e. Type 1 device: power consumption ≤ 1 μW, no downlink (DL) or uplink (UL) amplifier, feedback uplink signal through backscattering. The second type, i.e. Type 2a device: power consumption ≤ hundreds of μW, with DL and / or UL amplifier, feedback uplink signal through backscattering. The third type, i.e. Type 2b device: power consumption ≤ hundreds of μW, with DL and / or UL amplifier, autonomous generation of uplink signal. In the study of A-IoT, the reader communicating with the A-IoT device is called a reader, which can be a base station or a UE. The UE can be a mobile phone or other terminal device, such as a terminal device of 5G. In this application, the first communication node can be an A-IoT device. The second communication node can be a reader. In the A-IoT system, the time unit / resource unit is a chip, i.e. a chip corresponds to a bit 0 or a bit 1. Bit 0 corresponds to the low level of a chip, and bit 1 corresponds to the high level of a chip. After encoding and modulation, 1 bit of information can correspond to 1 or more chips. The time unit can be a basic unit for measuring time. The resource unit can be a basic unit for quantifying various resources in the system. The A-IoT downlink uses On-Off Keying (OOK)-1 or OOK-4 modulation. In some embodiments, the preamble does not need to be encoded, and each bit corresponds to a chip. In some embodiments, a chip corresponds to a modulation symbol, or a chip corresponds to any one OOK symbol in an OFDM symbol. Or a chip corresponds to the smallest time unit. In the A-IoT communication provided in this application, since the A-IoT device is simple and cannot continuously maintain the synchronization between the A-IoT device and the reader, before each uplink / downlink communication, a preamble sequence, i.e. first preamble information (also called downlink preamble) / second preamble information (also called uplink preamble) is needed for synchronization. The first preamble information is the preamble, also called the first preamble, also called the preamble. The second preamble information is the preamble, also called the second preamble, also called the preamble. The Internet of Things terminal device, also known as Internet of Things device, is generally simple in structure and low in complexity, and thus cannot perform complex processing. In order to enable the Internet of Things device to know that there is downlink signaling and start decoding, downlink preamble design is needed. When considering coexistence of an Ambient-IoT (A-IoT) system and an NR system, the present application also provides a transmission method of a downlink preamble (preamble) or a timing acquisition signal in an A-IoT system. The data transmission method provided by the present application is described in detail as follows: In an example embodiment, FIG. 1 is a flowchart of a data transmission method provided by an embodiment of the present application; the method can be applied to data transmission in an Internet of Things scenario to solve the problem of poor synchronization between the two parties in communication. The method can be executed by a data transmission apparatus provided by the present application, which can be realized by software and / or hardware and integrated on a first communication node. As shown in FIG. 1, the data transmission method provided by the present application includes the following steps: S110, obtaining first preamble information and first data. The first preamble information includes a start indication part and a clock acquisition part, and the time domain resource position of the first data is after the first preamble information. The first preamble information can be considered as a preamble, such as a signal sequence located before the time domain resource position of the first data. The first preamble information can be used for signal detection, synchronization and other operations of the first communication node. For example, the first preamble information indicates that the first communication node will soon obtain the first data. The first preamble information can determine the starting position of the signal. The first preamble information can also achieve time synchronization and frequency synchronization. Time synchronization can mean that the receiving end determines the starting time point of data transmission through the first preamble information, so as to accurately receive the subsequent data. Frequency synchronization can make the local oscillator frequency of the receiving end consistent with the sending end, ensuring the frequency accuracy of the received signal. The first preamble sequence can be used by the A-IoT device to determine the chip length of the data and / or control part, or to determine the M value corresponding to the data and / or control part. The A-IoT device uses the above information to decode and demodulate the data and / or control part. In this operation, the first preamble information can be a downlink preamble, which can be information transmitted by the reader to the first communication node. The start indication portion can be considered as information indicating the start position of the first preamble information. The start indication portion is a sub-part of the first preamble information and can indicate the start time of downlink signaling / downlink transmission at the receiving end. The downlink signaling / downlink transmission includes the first preamble information and the first data. In this embodiment, the start indication portion includes at least two types of chips with different M values, where M is the number of chips included in a transmission symbol. At least two different M values ​​can refer to the existence of at least two chip types in the communication system, where the number of chips (i.e., the M value) included in a transmission symbol for each chip type is different; that is, the number of chips included in a transmission symbol for each chip type is the M value, and the M value is different for each chip type. The specific values ​​of the at least two M values ​​are not limited and can be multiples of each other. Alternatively, at least two different M values ​​can refer to the start indication portion containing at least two chip lengths. The clock acquisition section can be considered as the part that acquires the clock signal for the receiving end. The time-domain resource location of the clock acquisition section can be located after the start indication section. The time-domain resource location indicates the signal's position on the time axis and can be used to describe the signal's distribution in the time dimension. The clock acquisition section is used to provide chip synchronization information. The first data can be considered as the data portion transmitted from the second communication node to the first communication node. The temporal resource position of the first data follows the first preamble information to facilitate parsing the first data using the preamble. When the temporal resource position of the first data follows the preamble information, it may mean that during communication, the receiving end first completes some necessary initialization and / or synchronization operations using the first preamble data before beginning to receive the actual data portion. IoT devices detect signals by detecting level transitions (rising edge: low level --> high level, falling edge: high level --> low level). Therefore, this application can detect the start of downlink signaling by detecting level transitions, such as detecting the start of downlink signaling in the first preamble information. This operation obtains the first preamble information and the first data, which can be considered as receiving the first preamble information and the first data from the second communication node. S120. Analyze the first data based on the first preamble information. After acquiring the first preamble information, the start indication portion and clock acquisition portion of the first preamble information are parsed. The first preamble information can be used to determine the start position of the first data and acquire the clock signal. Synchronization information is acquired for receiving the first data, and then the first data (also known as downlink data) is extracted and / or decoded. S130, in response to the first data, transmit the first sequence and the second data. After the first data is parsed, the second data can be fed back in response to the first data transmitted by the second communication node. For example, the second data is fed back to the second communication node. The first sequence can be considered as a sequence for detecting the second data. The time domain resource position of the first sequence can be located before the second data. The first sequence can include at least one of the following: second preamble information, midamble, postamble. The second preamble information is located before the second data, for example, the time domain position of the second preamble information is located before the second data. The midamble is inserted between the second data. The postamble is located after the second data, for example, the time domain position of the postamble is located after the second data. The first sequence can be used for sample frequency offset (SFO) estimation, for the reader to determine the length of the uplink chip, or for clock synchronization, etc. The first sequence can be used for channel estimation, so that the second data (also referred to as uplink data) can be better decoded. The downlink signaling / downlink transmission can include a preamble sequence (such as first preamble information), or control information, or downlink data (such as first data) to the Internet of Things device, and the Internet of Things device returns corresponding data or feedback information according to the received downlink signaling. For example, the downlink signaling includes a read command and a read position (content), and the Internet of Things device takes out the data at the indicated position and sends the corresponding data to the base station. For another example, the downlink signaling includes a write command, a write position, and data to be written, and the Internet of Things device stores the data sent by the downlink after receiving the downlink signaling at the indicated position. One downlink signaling contains a preamble (such as first preamble information) and data, such as first data (data is sent after the preamble). Or contains a preamble, control information and data (control information is after the preamble, and data is after the control information). The uplink signaling / uplink transmission includes the first sequence and the first data, and the uplink signaling mainly includes a preamble, data, etc., and returns information according to the downlink signaling. The first sequence in the present application can include a preamble (or a second preamble sequence). The first sequence is determined according to a target parameter. The target parameter can be a parameter set for determining the first sequence. The determined content is not limited here, such as determining one or more of the number, length, sequence and position of the first sequence. The determined manner is not limited here and can be associated with the content of the first sequence. The first sequence in the present application can include a midamble. The first sequence is determined according to a target parameter. The target parameter can be a parameter set for determining the first sequence. The determined content is not limited here, such as determining one or more of the number, length, sequence and position of the first sequence. The determined manner is not limited here and can be associated with the content of the first sequence. The first sequence in the application can include a tail sequence. The first sequence is determined according to a target parameter. The target parameter can be a parameter set for determining the first sequence. The determination content is not limited here, such as determining one or more of the number, length, sequence and position of the first sequence. The determination method is not limited here, which can be associated with the content of the first sequence. The first sequence is different, and the target parameter thereof can be the same or different, and the determined content thereof can also be the same or different. The data transmission method provided by the application acquires first preamble information and first data, parses the first data through the first preamble information, returns second data based on the first data, and returns a first sequence in the process of returning the second data, so as to facilitate the parsing of the second data. In the process of communication, the first preamble information for assisting in parsing the first data and the first sequence for assisting in parsing the second data are transmitted, thereby improving the synchronization of the two parties in communication. On the basis of the above-mentioned embodiments, variant embodiments of the above-mentioned embodiments are proposed. It should be noted that, in order to make the description brief, only the differences from the above-mentioned embodiments are described in the variant embodiments. In one embodiment, the start indication part includes two kinds of chips with M values, and the two kinds of M values are in a multiple relationship. In the embodiment, the start indication part can include at least two kinds of chips with different time lengths, also known as two kinds of chips with M values. The time length of the chip can be determined based on a transmission symbol, such as the number of chips on an Orthogonal Frequency-Division Multiplexing (OFDM) symbol, that is, M. The time length of the chip can be determined by dividing the time length of a transmission symbol by M. Downlink signaling can be transmitted on the transmission symbol. In the embodiment, the values of M in the two kinds of chips with M values are not specifically limited, as long as the two kinds of M values are in a multiple relationship. In one embodiment, the start indication part includes: chips with M values of 1 and 2, or chips with M values of 1 and 3, or chips with M values of 2 and 4, or chips with M values of 1 and 4. In the embodiment, the two kinds of M values can be 1 and 2; or 1 and 3; or 2 and 4; or 1 and 4. In one embodiment, the values of M in the two kinds of chips with M values are not specifically limited, and can not be in a multiple relationship. The embodiment only limits the value of M, and does not limit the number of chips and the order of chips. For example, the number of chips with a small M value can be at least one before the chips with a large M value, such as the time domain resource position. In one embodiment, the start indication part is determined by the M value corresponding to the first data. In the embodiment, the value of M corresponding to the start indication part can be determined with the value of M corresponding to the first data. For example, the M value corresponding to the chip in the start indication part is determined with the M value corresponding to the chip in the first data. The number of chips on one transmission symbol is the M value, and the start indication part and the first data part can correspond to different M values, respectively. The M value corresponding to the first data determines the M value corresponding to the start indication part. The embodiment does not limit the relationship between the M value of the first data and the M value of the start indication part. In one embodiment, when the M value corresponding to the first data and / or control is a first M value, the start indication part is a first start indication sequence or a first chip length (such as 1 and 2). When the M value corresponding to the first data and / or control is a second M value, the start indication part is a second start indication sequence or a second chip length (such as 1 and M). The first chip length includes one or more; the second chip length includes one or more. The first M value and the second M value can be different values, and the means for distinguishing the first M value and the second M value is not limited here. For example, it can be distinguished by whether it can be divided by a set value. The first start indication sequence and the second start indication sequence can be different sequences for indicating the start position of the downlink signaling. The first chip length and the second chip length can be information representing chips of different time lengths. The first chip length and the second chip length can be associated with the M value corresponding to the start indication part. When the M value corresponding to the first data is the first M value or the second M value, different start indication sequences and one or more different chip lengths can be corresponded. When the M value corresponding to the first data is the first M value, such as the remainder is a non-zero value when divided by 3, the M corresponding to the start indication part is 1 and 2 chips, respectively, that is, the first chip length is 2. When the M value corresponding to the first data is the second M value, such as a multiple of 3, the M corresponding to the start indication part is 1 and 3 chips, respectively, that is, the second chip length is 2. In one embodiment, the data transmission method further comprises: The control information includes at least one of the following: command type indication information, power control indication information. The command type indication information can be information indicating a downlink command type or a type of first data. The power control indication information can be considered as indication information related to power control. In some embodiments, the A-IoT device can determine whether to receive and / or decode the first data corresponding to the command type indication information according to the downlink command type information indicated by the command type indication information. For example, the command type indication information indicates that the downlink command is a first command (e.g., a paging command), and the A-IoT device to be checked will receive the corresponding first data. Other A-IoT devices (e.g., already checked or already received the paging command) will not receive the corresponding first data. For another example, the command type indication information indicates that the downlink command is a second command (e.g., Msg 1), and the A-IoT device to be checked that has not received the second command will receive the corresponding first data, and other A-IoT devices (e.g., already checked or already received the second command) will not receive the corresponding first data. For another example, the command type indication information indicates that the downlink command is a third command (e.g., Msg 4 or other), and the A-IoT device to be checked that has not received the third command will receive the corresponding first data, and other A-IoT devices (e.g., already checked or already received the third command) will not receive the corresponding first data. Whether the A-IoT device receives and / or decodes the first data is determined by the A-IoT device itself according to the received command type indication information. In one embodiment, the command type indication information indicates the type corresponding to the first data or command. Whether the A-IoT device receives and / or decodes the first data is determined by the A-IoT device itself according to the received command type indication information. In some embodiments, whether the A-IoT device receives and / or decodes the first data is determined by the A-IoT device state according to the received command type indication information. In one embodiment, the type corresponding to the first data / command includes at least one of the following: a first command, a second command, and a third command. The first command, the second command, and the third command can be different commands. The first command includes a paging command, the second command includes a downlink command after Msg 1, and the third command includes the remaining commands other than the first command and the second command or the third command includes a decrement command or a Msg 1 trigger command or a random access occasion range command. Or, The first command includes a command that all un-inventoried IoT devices (un-inventoried A-IoT devices within the range capable of receiving the downlink data) need to receive, the second command includes a command that devices receiving the first command need to receive, and the third command is a command that devices after sending message 1 need to receive. Alternatively, The first command includes a command that devices waiting for access need to receive, the second command includes a command that devices waiting to send message 1 after receiving the first command need to receive, and the third command includes a command that devices after sending message 1 need to receive. Alternatively, The first command includes a command that devices waiting for access need to receive, and the third command includes a command that devices after sending message 1 need to receive. Alternatively, The first command includes a command that devices need to receive before sending message 1, and the third command includes a command that devices need to receive after sending message 1. Wherein, the decreasing command, for example: repeated query command (such as QueryRep command). The paging command, for example, includes at least one of the following: Query (i.e. Query) command, Select command, QueryRep command, inventory command, paging. The remaining command, for example: read command, write command. The device waiting for access, for example, A-IoT device that has not received a paging command or has not sent Msg1. The device can be an IoT device, including a first communication node. The random access occasion range refers to the time of detecting the paging command, or the occasion of sending Msg1, or the time from sending msg1 to receiving msg4, or the specified random access time. In one embodiment, the type corresponding to the first data includes at least one of the following: paging related signaling, inventory related signaling, non-paging related signaling, access related signaling, signaling of downlink data transmission of specific devices (indicated by specific device identifier or device group identifier), downlink command after message 1, downlink command before message 1, and decreasing related command. In some embodiments, all downlink data commands are divided into N command types, and the command type indication information indicates one of the N command types. For example, the downlink data commands include at least one of the following: select command, Query command, decrement command, paging command, read command, write command, msg 2, msg 4, etc. These commands are divided into N command types. For example, N = 2, 3, 4. For example, the first command type includes at least a Query command or an inventory command or a command triggering msg 1, the second command type includes at least a decrement command, the third command type includes at least msg 2 and / or msg 4, and the fourth command type includes other commands not included in the other command types. The A-IoT device determines whether it needs to receive the downlink data according to the command type indication information. The message type, such as the type corresponding to the first data, indicates whether the R2D carries a command that needs to be received before the device sends Msg1 or a command that needs to be received after the device sends Msg1, thereby avoiding unnecessary R2D reception by devices that do not send Msg1. If there are 1024 devices being inventoried, the last device being inventoried can avoid receiving more than 1023 * x R2D, where x is the number of times (including retransmissions) that R2D is transmitted after Msg1, as well as Msg2, Msg4, etc. The decrement-related command indicates whether the device can send msg 1 or when the device can send Msg1. In one embodiment, the power control indication information indicates at least one of the following: whether the device performs signal amplification, or the device transmission power. The device transmission power can be the transmission power of the IoT device. In one embodiment, the setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information. In some embodiments, the control information can be transmitted at layer one (such as the physical layer). In some embodiments, the control information can be transmitted at layer two (such as the MAC layer). The control information can be transmitted at layer three (such as the RRC layer). In this embodiment, the control information includes setting information of the first type domain and indication information of the second type domain. The setting information is indicated by the indication information. The specific content of the setting information and the indication information is not limited here, as long as the setting information is indicated by the indication information. In one embodiment, the setting information includes one of the following: Whether the first type domain exists; The bit size of the first type domain. In one embodiment, the first type domain includes at least one of the following: The IoT device identity indication information, the code division multiplexing code indication information, the frequency resource allocation information, the frequency offset factor, the frequency offset factor set, the reader ID information, the chip duration, the modulation mode, the code rate, and the repetition number. The IoT device identity indication information can be information related to the IoT device, such as information related to the IoT device identity. The device-related RN (random number) information or the device-related device group identity. The code division multiplexing code indication information can be considered as indication information associated with code division multiplexing (CDM). For example, the CDM code sequence used, the sequence length, and the like. The frequency resource allocation information, also referred to as frequency resource allocation, can be information indicating the frequency domain resource allocation. In some embodiments, the frequency resource allocation information indicates the frequency location of the uplink transmission. The frequency offset factor can represent the relative offset degree between the actual frequency and the reference frequency. The frequency offset factor set can indicate a set composed of multiple frequency offset factors. The reader ID, also referred to as reader ID, can be considered as information identifying the reader, which can uniquely identify the reader. The chip duration, also referred to as chip duration, can be the time length of a chip. The modulation mode can be the mode of modulating the signal. The code rate, also referred to as coding rate. The repetition number can include the number of times the signal is repeatedly transmitted in the transmission process. In an embodiment, the second type domain includes at least one of the following: The command type indication information, the code division multiplexing enabling indication information, the frequency division multiplexing enabling indication information, the repetition enabling information, and the device type indication information. The code division multiplexing enabling indication information, also referred to as CDM enabling indication information, can be information indicating and / or controlling whether to enable code division multiplexing technology for communication. The frequency division multiplexing enabling indication information, also referred to as FDM enabling information, can be information indicating and / or controlling whether to include the indication associated with the frequency offset factor, or whether to enable the frequency division multiplexing technology communication, or the bit number / bit width of the frequency resource allocation indication domain. The repetition enabling information can be information controlling whether to repeatedly send the signal or data. The device type indication information can be information indicating a specific type of device participating in communication in the communication system, such as information indicating the types of the first communication node and the second communication node. For example, if the code division multiplexing enabling indication information indicates that code division multiplexing is enabled, the code division multiplexing code indication information exists; otherwise, the code division multiplexing code indication information does not exist. For example, if the frequency division multiplexing enabling indication information indicates that frequency division multiplexing is enabled, the number of bits of the frequency offset factor is A; otherwise, the number of bits of the frequency offset factor is B. A < B. For example, if the repetition enabling information indicates that repetition is enabled, the repetition number field exists; otherwise, the repetition number field does not exist. In one embodiment, the target parameter includes one or more of the following: The transport block size of the uplink data, the total number of bits of the uplink data, the number of bits of the uplink data after encoding and / or repetition, the transport code rate of the uplink data, the transport block size of the uplink data sub-block, the number of bits of the uplink data sub-block, the number of bits of the uplink data sub-block after encoding and / or repetition, the reader identifier information, the signaling indication information, and the first threshold value. The uplink data sub-block can be a data unit divided from the uplink data. The signaling indication information can be data indicating signaling related information. In one embodiment, the signaling indication information indicates at least one of the following: the index of the second preamble information, the index of the intermediate sequence in the first sequence, the index of the tail sequence in the first sequence, whether the intermediate sequence is used in the uplink data, the interval at which the intermediate sequence is inserted in the first sequence, whether the tail sequence is used in the uplink data, the first threshold value, and the number of intermediate sequences in the first sequence. The interval at which the intermediate sequence is inserted can be an indication that an intermediate sequence is inserted after every Y chips / OFDM symbols / bits / code words, also known as a midamble, or an intermediate sequence is inserted at the midamble position mentioned in this application. For example, a plurality of Y values are predefined, and one of the Y values is indicated by signaling. The number of inserted intermediate sequences is not limited here. It can be associated with the transmission length corresponding to the uplink data. In one embodiment, when the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, the repetition number of the uplink data) is greater than a first threshold, the number of inserted intermediate sequences is 3, when the corresponding transmission length of the uplink data is less than the first threshold and greater than a second threshold, the number of inserted intermediate sequences is 2, when the corresponding transmission length of the uplink data is less than the second threshold and greater than a third threshold, the number of inserted intermediate sequences is 1, and when the corresponding transmission length of the uplink data is less than the third threshold, the number of inserted intermediate sequences is 0. Wherein, the third threshold is less than the second threshold, and the second threshold is less than the first threshold; or, When the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, the repetition number of the uplink data) is greater than a first threshold, the number of inserted intermediate sequences is 2, when the corresponding transmission length of the uplink data is less than the first threshold and greater than a second threshold, the number of inserted intermediate sequences is 1, when the corresponding transmission length of the uplink data is less than the second threshold, the number of inserted intermediate sequences is 0, wherein the second threshold is less than the first threshold; or, When the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, the repetition number of the uplink data) is greater than a first threshold, the number of inserted intermediate sequences is 1, when the corresponding transmission length of the uplink data is less than the first threshold, the number of inserted intermediate sequences is 0. In one embodiment, the first sequence includes one or more of the following: second preamble information, intermediate sequence and tail sequence; the length relationship of the second preamble information, the intermediate sequence and the tail sequence satisfies one of the following: The length of the second preamble information is greater than the length of the tail sequence, the length of the tail sequence is greater than the length of the intermediate sequence, or; The length of the second preamble information is greater than the length of the tail sequence and the intermediate sequence, the length of the intermediate sequence is the same as the length of the tail sequence, or; The length of the second preamble information is a first set multiple of the length of the tail sequence, and the length of the tail sequence is a second set multiple of the length of the intermediate sequence. The first set multiple can be considered as a set multiple of the length between the second preamble information and the tail sequence. The second set multiple can be a set multiple of the length between the tail sequence and the intermediate sequence. The values of the first set multiple and the second set multiple are not limited here. In one embodiment, the first sequence is associated with the target parameter according to at least one of: The length of the one or more first sequences is determined according to the target parameter; The position of the one or more first sequences is determined according to the target parameter; The number of the one or more first sequences is determined according to the target parameter; The presence or absence of the one or more first sequences is determined according to the target parameter. In this embodiment, the length, position, number and presence or absence of the first sequence are associated with the target parameter. For example, the length or sequence code of the second preamble sequence is determined according to the first target parameter. For example, the length, position or number of the intermediate sequence is determined according to the second target parameter. For example, the length of the tail sequence or whether the tail sequence is used is determined according to the third target parameter. The first target parameter, the second target parameter and the third target parameter can be the same or different. The first target parameter, the second target parameter and the third target parameter can include one or more target parameters. In one embodiment, the data transmission method further comprises: If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold value, the corresponding intermediate sequence or tail sequence is not transmitted; otherwise, the intermediate sequence and the tail sequence are both transmitted; or If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold value, the corresponding intermediate sequence and tail sequence are not transmitted; otherwise, the intermediate sequence and the tail sequence are both transmitted; or When the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, and the repetition number of the uplink data) is less than the fifth threshold value, neither the intermediate sequence nor the tail sequence is transmitted; when the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, and the repetition number of the uplink data) is greater than the fifth threshold value and less than the sixth threshold value, the intermediate sequence or the tail sequence is transmitted; when the transmission length corresponding to the uplink data (the transmission length corresponding to the uplink data is related to at least one of the following: the transport block size of the uplink data, the number of chips of the uplink data, the chip length of the uplink data, the code rate of the uplink data, and the repetition number of the uplink data) is greater than the sixth threshold value, both the intermediate sequence and the tail sequence are transmitted. The values of the fourth threshold value, the fifth threshold value, and the sixth threshold value are not limited, as long as the sixth threshold value is greater than the fifth threshold value. The minimum number of time intervals can be the minimum value of the number of time intervals occupied by the data after the time domain resource position of the intermediate sequence. In an embodiment, the first sequence includes K discrete sequences. A discrete sequence refers to a time discrete sequence. In an embodiment, two adjacent discrete sequences in the K discrete sequences are separated by X chips, or Two adjacent discrete sequences in the K discrete sequences are separated by Y transmission symbols, or Two adjacent discrete sequences in the K discrete sequences are separated by Z bits, or Two adjacent discrete sequences in the K discrete sequences are separated by N codewords. K is a positive integer greater than or equal to 2. X, Y, Z, and N can be positive integers greater than or equal to 1. In an embodiment, the first sequence includes a second sequence and K third sequences, and the length of the second sequence is greater than the length of the third sequence. The second sequence can be referred to as a long sequence, and the third sequence can be referred to as a short sequence. In an embodiment, adjacent sequences in the first sequence are separated by a set number of chips, transmission symbols, bits, or codewords. The value of the set number is not limited here. It can be a pre-set number. In one example embodiment, the application also provides a data transmission method, and FIG. 2 is a flow diagram of another data transmission method provided by an embodiment of the application; the method can be applied to the case of data transmission for improving the synchronization of the two communication parties. The method can be executed by the data transmission device provided by the application, and the data transmission can be realized by software and / or hardware and integrated on the second communication node, such as a base station. The details of the embodiment not described in detail can refer to the above-mentioned embodiments, which will not be described here. As shown in FIG. 2, the application includes the following operations: S210, transmitting first preamble information and first data. The first preamble information includes a start indication part and a clock acquisition part, and the time domain resource position of the first data is after the first preamble information, and the first data is parsed based on the first preamble information. The operation can send the first preamble information and the first data to the first communication node. S220, obtaining a first sequence and second data. The first sequence is determined according to a target parameter, and the first sequence and the second data are contents in response to the first data transmission. The operation can obtain the first sequence and the second data transmitted by the first communication node. The second communication node can be a communication node in communication with the first communication node provided by the application. The second communication node provided by the embodiment of the application sends the first preamble information and the first data to the first communication node, and then obtains the first sequence and the second data from the first communication node. The first preamble information and the first sequence can assist the parsing of the first data and the second data, respectively, and improve the synchronization of the two communication parties. On the basis of the above-mentioned embodiments, variant embodiments of the above-mentioned embodiments are proposed, and it should be noted that, in order to make the description brief, only the differences between the variant embodiments and the above-mentioned embodiments are described in the variant embodiments. In one embodiment, the start indication part includes chips of two M values, and the two M values are in a multiple relationship. In one embodiment, the start indication part includes: chips of M values of 1 and 2, or; chips of M values of 1 and 3, or; chips of M values of 2 and 4, or; chips of M values of 1 and 4. In one embodiment, the start indication part is determined by the M value corresponding to the first data. In one embodiment, when the M value corresponding to the first data is a first M value, the start indication part is a first start indication sequence or a first chip length. The start indication part is a second start indication sequence or a second chip length when the M value corresponding to the first data is a second M value; wherein the first chip length includes one or more; and the second chip length includes one or more. In one embodiment, the data transmission method further comprises: Transmitting control information, the control information including at least one of the following: command type indication information, power control indication information. In one embodiment, the command type indication information indicates a type required to be received by the first data or command. In one embodiment, the type corresponding to the first data includes at least one of the following: a first command, a second command, and a third command. In one embodiment, the first command includes a paging command, the second command includes a downlink command after message 1, and the third command includes a remaining command other than the first command and the second command or the third command includes a decrement command or a message 1 trigger command or a random access occasion range command. Alternatively, The first command includes a command required to be received by all unmonitored Internet of Things devices, the second command includes a command required to be received by devices after receiving the first command, and the third command is a command required to be received by devices after sending message 1. Alternatively, The first command includes a command required to be received by devices waiting for access, the second command includes a command required to be received by devices waiting to send message 1 after receiving the first command, and the third command includes a command required to be received by devices after sending message 1. Alternatively, The first command includes a command required to be received by devices waiting for access, and the third command includes a command required to be received by devices after sending message 1. Alternatively, The first command includes a command required to be received by devices before sending message 1, and the third command includes a command required to be received by devices after sending message 1. In one embodiment, the type of downlink data includes at least one of the following: paging-related signaling, monitoring-related signaling, non-paging-related signaling, access-related signaling, signaling for downlink data transmission of a specific device, and downlink command after message 1. In one embodiment, the power control indication information indicates at least one of the following: whether the device amplifies the signal, or the device transmission power. In one embodiment, the setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information. In an embodiment, the configuration information comprises one of the following: whether the first type field exists; bit size of the first type field. In an embodiment, the first type field comprises at least one of the following: Internet of Things device identification indication information, code division multiplexing code indication information, frequency resource allocation information, frequency offset factor, frequency offset factor set, reader identification information, chip duration, modulation mode, code rate, repetition number. In an embodiment, the second type field comprises at least one of the following: command type indication information, code division multiplexing enabling indication information, frequency division multiplexing enabling indication information, repetition enabling information, device type indication information. In an embodiment, the target parameter comprises one or more of the following: transmission block size of uplink data, total number of bits of uplink data, number of bits of uplink data after encoding and / or repetition, transmission code rate of uplink data, transmission block size of uplink data sub-block, number of bits of uplink data sub-block, number of bits of uplink data sub-block after encoding and / or repetition, reader identification information, signaling indication information, first threshold value. In an embodiment, the signaling indication information indicates at least one of the following: index of second preamble information, index of intermediate sequence in the first sequence, index of tail sequence in the first sequence, whether intermediate sequence is used in uplink data, interval of insertion of intermediate sequence in the first sequence, whether tail sequence is used in uplink data, first threshold value, number of intermediate sequences in the first sequence. In an embodiment, when the transmission length corresponding to the uplink data is greater than the first threshold value, the number of inserted intermediate sequences is 3, when the transmission length corresponding to the uplink data is less than or equal to the first threshold value and greater than the second threshold value, the number of inserted intermediate sequences is 2, when the transmission length corresponding to the uplink data is less than or equal to the second threshold value and greater than the third threshold value, the number of inserted intermediate sequences is 1, and when the transmission length corresponding to the uplink data is less than or equal to the third threshold value, the number of inserted intermediate sequences is 0. Wherein, the third threshold value is less than the second threshold value, and the second threshold value is less than the first threshold value; or, when the transmission length corresponding to the uplink data is greater than the first threshold value, the number of inserted intermediate sequences is 2, when the transmission length corresponding to the uplink data is less than or equal to the first threshold value and greater than the second threshold value, the number of inserted intermediate sequences is 1, and when the transmission length corresponding to the uplink data is less than or equal to the second threshold value, the number of inserted intermediate sequences is 0. Wherein, the second threshold value is less than the first threshold value; or, When the transmission length corresponding to the uplink data is greater than the first threshold, the number of inserted intermediate sequences is 1, and when the transmission length corresponding to the uplink data is less than or equal to the first threshold, the number of inserted intermediate sequences is 0. In one embodiment, the first sequence includes one or more of the following: second preamble information, an intermediate sequence, and a tail sequence; and a length relationship of the second preamble information, the intermediate sequence, and the tail sequence satisfies one of the following: The length of the second preamble information is greater than the length of the tail sequence, the length of the tail sequence is greater than the length of the intermediate sequence, or; The length of the second preamble information is greater than the length of the tail sequence and the length of the intermediate sequence, the length of the intermediate sequence is the same as the length of the tail sequence, or; The length of the second preamble information is a first set multiple of the length of the tail sequence, and the length of the tail sequence is a second set multiple of the length of the intermediate sequence. In one embodiment, the first sequence is associated with a target parameter, and the association includes at least one of the following: The length of one or more of the first sequences is determined according to the target parameter; The position of one or more of the first sequences is determined according to the target parameter; The number of one or more of the first sequences is determined according to the target parameter; The presence or absence of one or more of the first sequences is determined according to the target parameter. In one embodiment, the data transmission method further includes: Receiving one or more of the intermediate sequence and the tail sequence. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold, the corresponding intermediate sequence or tail sequence is not transmitted. When the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is greater than or equal to the fourth threshold, both the intermediate sequence and the tail sequence are received. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold, neither the corresponding intermediate sequence nor the tail sequence is transmitted. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is greater than or equal to the fourth threshold, both the intermediate sequence and the tail sequence are received. When the transmission length corresponding to the uplink data is less than the fifth threshold, neither the intermediate sequence nor the tail sequence is transmitted. When the transmission length corresponding to the uplink data is greater than or equal to the fifth threshold and less than the sixth threshold, the intermediate sequence or the tail sequence is received. When the transmission length corresponding to the uplink data is greater than or equal to the sixth threshold, the intermediate sequence and the tail sequence are received. In one embodiment, the first sequence includes K discrete sequences. In one embodiment, two adjacent discrete sequences in the K discrete sequences are separated by X chips; or, two adjacent discrete sequences in the K discrete sequences are separated by Y transmission symbols; or, two adjacent discrete sequences in the K discrete sequences are separated by Z bits; or, two adjacent discrete sequences in the K discrete sequences are separated by N codewords. In one embodiment, the first sequence includes a second sequence and K third sequences, and the length of the second sequence is greater than the length of the third sequence. In one embodiment, two adjacent sequences in the second preamble information are separated by a set number of chips, transmission symbols, bits, or codewords. The present application is exemplarily described below. The present application is directed to data transmission of Internet of Things devices, and a sequence of signaling / signal is designed. The designed signaling / signal can be applied in a low-complexity system to achieve data transmission. In one embodiment, the present embodiment provides a transmission scheme of a downlink preamble. In the present embodiment, the first preamble information, i.e., the downlink preamble (preamble) or the time acquisition signal, includes two parts, a start indication part and a clock acquisition part. The clock acquisition part is immediately followed by the start indication part. In the present embodiment, the start indication part can include chips of two M values in a multiple relationship, which are exemplarily described as follows: In some embodiments, the start indication part includes chips of M=1 and chips of M=2. For example, the start indication part is one high-level chip of M=1, one low-level chip of M=2, and one high-level chip of M=2. Figure 3 is a schematic diagram of a start indication part according to an embodiment of the present application. As shown in Figure 3, the high level of M=1 is used to indicate the start of the downlink signaling (change of received signal energy) for the A-IoT device, and the two low levels of M=2 are used to indicate the length of an OFDM symbol. The length of an OFDM symbol is fixed, and M=1 indicates that there is only one chip in an OFDM symbol. The greater the value of M, the smaller the length of the chip. For example, the start indication part includes one high level chip of M=1 and one low level chip of M=2. In this embodiment, the overhead of the start indication part is reduced. Figure 4 is a schematic diagram of another start indication part according to an embodiment of the present application. As shown in Figure 4, the start indication part includes one high level chip of M=1 and one low level chip of M=2. In some embodiments, the start indication part includes a chip of M=1 and a chip of M=3. For example, the start indication part includes one high level chip of M=1 and one low level chip of M=3. For example, the start indication part includes one high level chip of M=1, one low level chip of M=3, and one high level chip of M=3. For example, the start indication part includes one high level chip of M=1 and two consecutive low level chips of M=3. Figure 5 is a schematic diagram of another start indication part according to an embodiment of the present application. As shown in Figure 5, the start indication part includes one high level chip of M=1, one low level chip of M=3, one high level chip of M=3, and one low level chip of M=3. Figure 6 is a schematic diagram of another start indication part according to an embodiment of the present application. As shown in Figure 6, the start indication part includes one high level chip of M=1, two consecutive low level chips of M=3, and one high level chip of M=3. In some embodiments, a downlink signaling includes at least a downlink preamble (e.g., a first preamble information) and data (e.g., a first data). When the M value corresponding to the first data cannot be divided by 3, the start indication part in the downlink preamble includes a chip of M=1 and a chip of M=2. When the M value corresponding to the data can be divided by 3, the start indication part in the downlink preamble includes a chip of M=1 and a chip of M=3. For details, refer to the above embodiments, which will not be described here. In some embodiments, the length of the continuous high level of the start indication part is greater than the length of the continuous low level. For example, the start indication part includes one continuous high level and one continuous low level, and the length of the continuous high level is a set multiple of the length of the continuous low level, such as twice. For example, the start indication part includes i continuous high levels and j continuous low levels, and the length of at least one continuous high level is greater than the maximum length of the j continuous low levels. The continuous high / low level can refer to a plurality of continuous '1' / '0', each '1' / '0' representing a high level / low level of one chip. In some embodiments, the total length of all high level chips in the start indication part is greater than the total length of all low level chips. In some embodiments, the number of chips of the clock acquisition part is related to the M value of the clock acquisition part. For example, when the M value of the clock acquisition part <= a seventh threshold value, the number of chips of the clock acquisition part is A, when the M value of the clock acquisition part > the seventh threshold value and <= an eighth threshold value, the number of chips of the clock acquisition part is B, and when the M value of the clock acquisition part > the second threshold value, the number of chips of the clock acquisition part is C. The seventh threshold value < the eighth threshold value, A < B < C. For example, the seventh threshold value = 8, the eighth threshold value = 16 or 24. For example, A = 3 or 5, B = 5 or 7, and C = 7 or 9 or a positive integer greater than 7. For example, the seventh threshold value = 8, the eighth threshold value = 16 or 24. For example, A = 4 or 5, B = 6 or 7, and C = 8 or 9 or a positive integer greater than 7. For example, when the M value of the clock acquisition part <= a seventh threshold value, the number of chips of the clock acquisition part is A, and when the M value of the clock acquisition part > the seventh threshold value, the number of chips of the clock acquisition part is B. The more the number of chips of the clock acquisition part, the higher the miss detection rate (MDR), but at the same time, the false detection rate (FDR) is reduced. When the M value is small, the length of each chip is large, so even if the number of chips is small, the FDR is not greatly affected, and when the M value is large, the length of each chip is short, and if the number of chips is small, the FDR is increased, affecting the performance. Therefore, different numbers of chips are selected for different M values. Since the number of chips of the clock acquisition part varies at different M values, in order for the device to know the end of the clock acquisition part, the clock acquisition part can also include end indication information. The end indication information is a predetermined sequence. When the device detects the end indication information, it knows that the clock acquisition part has ended. In some embodiments, the number of chips of the clock acquisition part is related to the M value of the control information or data. As above In some embodiments, the length of the clock acquisition part is greater than or equal to 1 / 2 (0.5) OFDM symbol length. In some embodiments, the length of the clock acquisition part is greater than or equal to 1 OFDM symbol length. In some embodiments, the number of chips of the clock acquisition part is related to the device type. In some embodiments, the wake-up / activation indication information is carried in the following one: the start indication part, the clock acquisition part, the preamble. The start indication part, the clock acquisition part, and the preamble have multiple patterns / sequences, wherein one pattern / sequence represents wake-up / activation, and another pattern / sequence represents non-wake-up / non-activation. In one embodiment, the embodiment provides a downlink control information, i.e., control information, which carries some indication information for indicating the information related to the downlink or uplink data transmission, and / or the information related to the device state. In some embodiments, the wake-up / activation indication information is carried in the downlink signaling. In some embodiments, the wake-up / activation indication information is indicated in the control information. The wake-up / activation indication information is used to indicate the device to start decoding / receiving the downlink signaling, or to indicate the device to switch to the wake-up / activation / on-duty state. For example, the wake-up / activation indication information is 1 bit, wherein the bit ‘1’ represents wake-up / activation, and the bit ‘0’ represents non-wake-up / non-activation indication. In some embodiments, the control information at least includes one or more of the command type indication information, the ID indication information, or the device type indication information. In some embodiments, the control information at least includes the command type indication information and the ID indication information. The command type indication information and the ID indication information are indicated in different domains. For example, the command type indication information is transmitted in one domain of the control information of L1, and the ID indication information is transmitted in L2 or L3. For example, the command type indication information and the ID indication information are indicated in different domains of the control information of L1. The meaning of the command type indication information is as follows: The command type indication information can indicate that the downlink signaling is signaling before access procedure, or during access procedure, or after access procedure. The command type indication information can indicate that the downlink signaling is signaling before access procedure, or during access procedure, or after access procedure. The command type indication information can indicate that the downlink signaling is signaling before Msg 1, or after Msg 1. The command type indication information can indicate that the downlink signaling is signaling before Msg 1, or after Msg 1 before Msg 3, or after Msg 3. The command type indication information can indicate that the downlink signaling is signaling before Msg 1, or during paging, or after access. The command type indication information can indicate the command type of the downlink signaling (e.g., inventory, Q minus, Q value, paging, read / write, etc.). The command type indication information can indicate which devices should receive the downlink signaling. The command type indication information can indicate paging inventory related signaling, access related signaling (e.g., msg2, msg4) signaling (or command or data), downlink data transmission, or other commands. The command type indication information can indicate access related signaling (e.g., msg2, msg4) related signaling, or not. The command type indication information can indicate synchronization or wake-up related signaling, or not. The synchronization or wake-up indication can include the content in the above embodiments. For example, the command type indication information has 2 bits. The 2 bits indicate that the downlink signaling is a paging command, a pre-access command (Q minus, etc.), or a post-access command. The paging command is received by all devices (e.g., all un-inventoried A-IoT devices). The pre-access command is received by devices that have received the paging command. The post-access command is received only by devices that have sent Msg 1. The command type indication information can indicate that the downlink signaling is sent to all devices, or to a group of devices, or to one device. For example, the command type indication information has 2 bits. The 2 bits indicate that the downlink signaling is a paging command, a pre-access command (Q minus, etc.), or a post-access command, or other commands. For example, the command type indication information has 1 bit. The 1 bit indicates that the downlink signaling is a paging command or other command. For example, the command type indication information has 1 bit. The 1 bit indicates that the downlink signaling is a pre-Message 1 command or a post-Message 1 command. The pre-Message 1 command means that the device can send Message 1 after the command or the command triggers Message 1 transmission. The post-Message 1 command means that the command is a reply to the sending of Message 1, or a command for a single device or a plurality of specific devices. The device can determine whether to receive / decode the command (or the signaling or the data) according to the command type indication information and / or the device state. The ID indication information can be device identification related information, device related RN (random number) information, or device related device group identification. Different ID indication information can correspond to different number of bits. Or the domain size of different ID indication information is different. In some embodiments, the ID indication information, also known as identification indication information (such as Internet of Things device identification indication information), can be an inventory process ID. For example, 1 bit indicates the device currently being inventoried or all devices. The ID indication information indicates whether the related downlink signaling transmission is related to all devices or specific devices. In some embodiments, the presence or absence of the first type domain in the control information or the bit size (bit width) of the first type domain is determined according to the indication information of the second type domain in the control information, i.e. the setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information. The first type domain includes at least one of the following: ID information, CDM code indication, frequency resource allocation, frequency offset factor, reader ID, chip duration, modulation method, code rate, and repetition number. The second type includes at least one of the following: command type indication information, CDM enabling indication information, FDM enabling indication information, repetition enabling information, device type indication information, and data format. Frequency offset factor: the frequency offset factor can be used to derive the frequency offset between the frequency point position of the uplink (D2R) signaling transmission and the downlink carrier wave, or to indicate the chip length of the D2R signaling, or to indicate the bandwidth of the D2R signaling, or to indicate the code rate. Bandwidth of D2R signaling = 2 / (chip length of D2R signaling * frequency offset factor). The frequency offset factor has a corresponding relationship with the bandwidth, code rate, and chip length. For example, when the bandwidth is 30kHZ and the frequency offset factor is 2, the chip length of the D2R signaling is 33.33us. In some embodiments, the frequency offset factor is equal to the repetition number of the line code. Data format: indicates the format of the downlink signaling. For example, the content includes the following. In some embodiments, the domain size (bit number / bit width) of the ID indication information is determined according to at least one of the following: command type indication information, device type indication information. For example, the command type indication information has 2 bits. The 2 bits indicate that the downlink signaling is a paging command, a pre-access command (Q minus, etc.), or a post-access command. Among them, the paging command is received by all devices and does not include the ID indication information domain. The pre-access command is received by the device after receiving the paging command, including device identification related indication or device group identification indication. The post-access command is only received by the device after sending Msg1, including device identification related indication or device group identification indication. For example, when the command type indicates that the downlink signaling is sent to all devices, i.e., device (or information before msg 1), there is no ID indication information in the control information; when the command type indicates that the downlink signaling is sent to the device group (or during paging, or Msg 2), the ID indication information in the control information is the device group identification information; when the command type indicates that the downlink signaling is sent to a specific device (or after msg 3 or after access), the ID indication information in the control information is the device related ID information or the device related RN information. For example, when the device type indication information indicates that the downlink signaling is sent to device type 2b, the ID indication information in the control information is the device related ID information; when the device type indication information indicates that the downlink signaling is sent to device type 1 or device type 2a, the ID indication information in the control information is the device related RN information. For example, when the command type indicates that the downlink signaling is sent to all devices (or information before Msg 1), there is no ID indication information in the control information; when the command type indicates that the downlink signaling is sent to a device group (or during paging, or Msg 2), the ID indication information in the control information is device group ID information; when the command type indicates that the downlink signaling is sent to a specific device (or after Msg 3 or after access), according to the device type, determine the ID indication information in the control information device-related ID information, or device-related RN information. In some embodiments, the control information includes CDM code indication information. The CDM code indication information indicates at least one of the following: CDM code used by the device for uplink transmission, CDM code sequence length used by the device for uplink transmission, maximum sequence set number of CDM codes that can be used by the device for uplink transmission, and CDM code sequence optional set information used by the device for uplink transmission. The maximum sequence set number of CDM codes that can be used by the device for uplink transmission: the maximum number of sequences that can be multiplexed by CDM. For example, if the maximum sequence set number is 4, then at most 4 CDM codes can be multiplexed, i.e. at most 4 users can be multiplexed. The CDM code sequence optional set used by the device for uplink transmission. The device can select one CDM code from the optional set for use. In some embodiments, the control information includes CDM enabling indication information. The CDM enabling indication information indicates whether CDM transmission is performed for device uplink transmission. The CDM enabling indication information indicates whether CDM code indication information is included in the control information. In some embodiments, the control information includes maximum frequency offset coefficient and / or frequency offset factor set indication. The maximum frequency offset coefficient indicates the maximum frequency offset between the frequency point position of the uplink (D2R) signaling transmission and the downlink carrier wave (CW). The frequency offset factor set indicates a set of one or more frequency offset factors. The frequency offset factor set can be at least one of the following: {1, 2, 4, 8, 16}, {2, 4, 8, 16}, {8, 16}, {2, 4, 8}, {4, 8, 16}. For example, a plurality of frequency offset factor sets are predefined, and the base station indicates one of the frequency offset factor sets. The device selects one frequency offset factor from the indicated frequency offset factor set to transmit the uplink signal. In some embodiments, the frequency offset factor sets are different for different D2R signaling types (because the information bit length is different). In some embodiments, the frequency offset factor set indication is included in the control information. If the number of frequency offset factors in the indicated frequency offset factor set is greater than 1, it means that FDM is enabled. In some embodiments, the FDM enable information is included in the control information. The FDM enable information indicates that the downlink signaling includes the frequency offset factor set indication, or includes the frequency offset factor indication. For example, the FDM enable information is 1 bit, ‘1’ means that FDM is enabled, and the downlink signaling includes the frequency offset factor set indication; ‘0’ means that FDM is not enabled, and the downlink signaling includes the frequency offset factor indication. For example, the FDM enable information is 1 bit, ‘1’ means that FDM is enabled, and the downlink signaling includes the frequency offset factor set indication; ‘0’ means that FDM is not enabled, and the downlink signaling does not include the frequency offset factor indication nor the frequency offset factor set indication. The device performs D2R signaling transmission according to the predefined information. In some embodiments, the FDM enable information is included in the control information. The FDM enable information indicates whether the device uplink transmission is FDM transmission. The FDM enable information indicates the bit number / bit width of the frequency resource allocation indication field in the control information. In some embodiments, the FDM enable information is in the frequency resource allocation indication field. For example, the first bit in the frequency resource allocation indication field is the FDM enable information. The length of the frequency resource allocation field is determined according to the FDM enable information. In some embodiments, the format of the control information is determined according to the indication information of the second type field in the control information. In some embodiments, the format of the control information indicates at least one of: fields included in the control information, ordering of the fields. In one embodiment, the present embodiment provides a scheme of lengths of uplink preamble (e.g., second preamble information), midamble (e.g., midamble sequence), postamble sequence (e.g., postamble sequence). In some embodiments, the length of the first sequence is related to a first parameter, i.e., a target parameter. The first parameter includes at least one of: transport block size (TBS) of the uplink data, total number of bits of the uplink data, number of bits of the uplink data after encoding and / or repetition, transmission code rate of the uplink data, TBS of the uplink data sub-block, number of bits of the uplink data sub-block, number of bits of the uplink data sub-block after encoding and / or repetition, uplink chip rate, downlink chip rate, repetition number. The chip rate can correspond to a chip length. It represents the number of chips transmitted per unit time. The first sequence is at least one of: preamble, midamble, postamble. The first sequence can be arranged in order of first preamble information, midamble, and postamble sequence. The time domain resource positions of the first preamble sequence, midamble, and postamble sequence are sequentially increasing. The first preamble sequence can be the sequence with the earlier time domain resource position. The midamble sequence can be the sequence located in the middle. The postamble sequence can be the sequence located at the tail. For example, when the first parameter is greater than a ninth threshold value, the length of the first sequence is D, and when the first parameter is less than or equal to the ninth threshold value, the length of the first sequence is E. Wherein the ninth threshold value is a positive integer greater than or equal to 300, D, E are positive integers greater than or equal to 8, and D > E. For example, when the first parameter is greater than a tenth threshold value, the length of the first sequence is D, when the first parameter is less than or equal to the tenth threshold value and greater than an eleventh threshold value, the length of the first sequence is E, and when the first parameter is less than or equal to the eleventh threshold value, the length of the first sequence is F. Wherein the tenth threshold value is a positive integer less than or equal to 300, D, E, C are positive integers greater than or equal to 8, and D > E > F. For example, when the first parameter is greater than a tenth threshold value, the number of the first sequences (e.g., midamble, or postamble, or preamble) is D, when the first parameter is less than or equal to the tenth threshold value and greater than an eleventh threshold value, the number of the first sequences is E, and when the first parameter is less than or equal to the eleventh threshold value, the number of the first sequences is F. Wherein the tenth threshold value is a positive integer less than or equal to 300, D, E, F are positive integers greater than or equal to 0, and D > E > F. For example, when the first parameter is greater than a tenth threshold value, the number of the first sequences (e.g., midamble, or postamble, or preamble) is G, when the first parameter is less than or equal to the tenth threshold value and greater than an eleventh threshold value, the number of the first sequences is H, when the first parameter is less than or equal to the eleventh threshold value and greater than or equal to a twelfth threshold value, the number of the first sequences is P, when the first parameter is greater than the twelfth threshold value, the number of the first sequences is Q. Wherein the tenth threshold value is a positive integer less than or equal to 300, G, H, P, Q are positive integers greater than or equal to 0, G > H > P > Q. The tenth threshold value is greater than the eleventh threshold value, which is greater than the twelfth threshold value, which is greater than the thirteenth threshold value. For example, when the first parameter is greater than a tenth threshold value, the number of the first sequences (e.g., midamble, or postamble, or preamble) is D, when the first parameter is less than or equal to the tenth threshold value, the number of the first sequences is E. Wherein the tenth threshold value is a positive integer less than or equal to 300, D, E are positive integers greater than or equal to 0, D > E. For example, the first parameter is the transmission rate of the uplink data, when the transmission rate is less than or equal to a fourteenth threshold value, the length of the first sequence is A'; when the transmission rate is greater than the fourteenth threshold value, the length of the first sequence is B'. Wherein the fourteenth threshold value is a value less than or equal to 1 kps. A' > B'. For example, the first parameter is the transmission rate of the uplink data, when the transmission rate is less than or equal to a fifteenth threshold value, the number of the first sequences is A"; when the transmission rate is greater than the fifteenth threshold value, the length of the first sequence is B". Wherein the fifteenth threshold value is a value less than or equal to 1 kps. A" > B". For example, the first parameter is the transmission rate of the uplink data, when the transmission rate is less than or equal to a fifteenth threshold value, the number of the first sequences is A"; when the transmission rate is greater than the fifteenth threshold value and less than or equal to a sixteenth threshold value, the number of the first sequences is B". When the transmission rate is greater than the sixteenth threshold value, the number of the first sequences is C". Wherein the fifteenth threshold value is a value less than or equal to 1 kps. A" > B" > C". For example, the first parameter is the transmission rate of the uplink data, when the transmission rate is less than or equal to a fourteenth threshold value, the length of the first sequence is A'; when the transmission rate is greater than the fourteenth threshold value and less than or equal to a seventeenth threshold value, the length of the first sequence is B'. When the transmission rate is greater than the seventeenth threshold value, the length of the first sequence is C'. Wherein the fourteenth threshold value is a value less than or equal to 1 kps. A' > B' > C'. For example, the first parameter is the chip rate of the uplink, when the chip rate is less than or equal to an eighteenth threshold value, the length of the first sequence is D'; when the chip rate is greater than the eighteenth threshold value, the length of the first sequence is E'. Wherein the eighteenth threshold value is a value less than or equal to 1 kps. D' > E'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the nineteenth threshold value, the number of the first sequence is F'; when the chip rate is greater than the nineteenth threshold value, the length of the first sequence is G'. The nineteenth threshold value is less than or equal to 1 kps. F'>G'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the nineteenth threshold value, the number of the first sequence is F'; when the chip rate is greater than the nineteenth threshold value and less than or equal to the twentieth threshold value, the number of the first sequence is G'. When the chip rate is greater than the fifth threshold value, the number of the first sequence is P'. The nineteenth threshold value is less than or equal to 1 kps. F'>G'>P'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the eighteenth threshold value, the length of the first sequence is D'; when the chip rate is greater than the eighteenth threshold value and less than or equal to the twenty-first threshold value, the length of the first sequence is E'. When the chip rate is greater than the twenty-first threshold value, the length of the first sequence is Q'. The eighteenth threshold value is less than or equal to 1 kps. D'>E'>Q'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the eighteenth threshold value, the length of the first sequence is D'; when the chip rate is greater than the eighteenth threshold value and less than or equal to the twenty-first threshold value, the length of the first sequence is E'. When the chip rate is greater than the twenty-first threshold value, the length of the first sequence is Q'. The eighteenth threshold value is less than or equal to 1 kps. D'>E'>Q'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the eighteenth threshold value, the length of the first sequence is D'; when the chip rate is greater than the eighteenth threshold value and less than or equal to the twenty-first threshold value, the length of the first sequence is E'. When the chip rate is greater than the twenty-first threshold value, the length of the first sequence is Q'. The eighteenth threshold value is less than or equal to 1 kps. D'>E'>Q'. For example, the first parameter is the chip rate of the uplink data, when the chip rate is less than or equal to the eighteenth threshold value, the length of the first sequence is D'; when the chip rate is greater than the eighteenth threshold value and less than or equal to the twenty-first threshold value, the length of the first sequence is E'. When the chip rate is greater than the twenty-first threshold value, the length of the first sequence is Q'. The eighteenth threshold value is less than or equal to 1 kps. D'>E'>Q'. For example, the first parameter is the chip rate of the downlink data, when the chip rate is less than or equal to the twenty-second threshold value, the length of the first sequence is A; when the chip rate is greater than the twenty-second threshold value and less than or equal to the twenty-sixth threshold value, the length of the first sequence is B. When the chip rate is greater than the twenty-sixth threshold value, the length of the first sequence is C. Wherein the twenty-second threshold value is less than or equal to 1 kps. A > B > C. For example, the first parameter is the repetition number, when the repetition number is less than or equal to the twenty-seventh threshold value, the length of the first sequence is A; when the repetition number is greater than the twenty-seventh threshold value, the length of the first sequence is B. Wherein the twenty-seventh threshold value is less than or equal to 2. A < B. For example, the first parameter is the repetition number, when the repetition number is less than or equal to the twenty-eighth threshold value, the length of the first sequence is A; when the repetition number is greater than the twenty-eighth threshold value, the length of the first sequence is B. Wherein the twenty-eighth threshold value is less than or equal to 2. A < B. For example, the first parameter is the repetition number, when the repetition number is less than or equal to the twenty-eighth threshold value, the length of the first sequence is A; when the repetition number is greater than the twenty-eighth threshold value and less than or equal to the twenty-ninth threshold value, the length of the first sequence is B. When the repetition number is greater than the twenty-ninth threshold value, the length of the first sequence is C. Wherein the twenty-eighth threshold value is less than or equal to 2. A < B < C. For example, the first parameter is the repetition number, when the repetition number is less than or equal to the twenty-seventh threshold value, the length of the first sequence is A; when the repetition number is greater than the twenty-seventh threshold value and less than or equal to the thirtieth threshold value, the length of the first sequence is B. When the repetition number is greater than the thirtieth threshold value, the length of the first sequence is C. Wherein the twenty-seventh threshold value is less than or equal to 2. A < B < C. The values of A, B and C in each embodiment in the present application can be the same or different, which is not limited here. It should be noted that the first parameters corresponding to different first sequences (preamble, or midamble or postamble) can be the same or different, and the threshold values corresponding to different first sequences can be the same or different. For example, the first parameter is the TBS of the uplink data and the transmission code rate of the uplink data, when the TBS of the uplink data is greater than or equal to the thirty-first threshold value, and the transmission code rate of the uplink data is less than the thirty-second threshold value, the length or number of the first sequence is A; otherwise, the length or number of the first sequence is B. Wherein the thirty-first threshold value is a positive integer greater than or equal to 300, the thirty-second threshold value is a value less than or equal to 1 kps, A and B are positive integers greater than or equal to 8, and A > B. In some embodiments, when the uplink uses FDM, multiple first sequences are included. Different first sequences are used by the devices that perform FDM transmission on the uplink. For example, device 1 and device 2 are frequency division multiplexed, the preamble / postamble of device 1 and the preamble / postamble of device 2 use different sequences. The first sequence can be an M sequence, a Golay sequence, a Golay sequence, a PN sequence, an RS sequence, an RM sequence, a Barker code sequence, a predefined sequence, etc. The first sequence can be an M sequence, a Golay sequence, a Golay sequence, a PN sequence, an RS sequence, an RM sequence, a Barker code, a predefined sequence after Manchester coding. The number of minimum consecutive 1s or minimum consecutive 0s in different sequences is different. For example, 11001111001100001111, the number of minimum consecutive 1s or minimum consecutive 0s is 2, and the sequence 11110000000011111111, the number of minimum consecutive 1s or minimum consecutive 0s is 4. The number of minimum consecutive 1s or minimum consecutive 0s in different sequences is different, and the corresponding bandwidths are different, which can be frequency division multiplexed. In some embodiments, the lengths of different sequences are the same. In some embodiments, the lengths of preamble, midamble, and postamble can be different. For example, the length of preamble is greater than the length of postamble, and the length of postamble is greater than the length of midamble. For example, the length of preamble is greater than the length of postamble and midamble, and the length of midamble is the same as the length of postamble. For example, the length of preamble is N (e.g., 2, 3, 4, 5, 6, 7, 8) times the length of postamble, and the length of postamble is M (e.g., 2, 3, 4, 5, 6, 7, 8) times the length of midamble. For example, the length of preamble is N (e.g., 2, 3, 4, 5, 6, 7, 8) times the length of postamble, and the length of postamble is greater than the length of midamble. For example, the length of preamble is greater than the length of midamble, and the length of midamble is greater than the length of postamble. For example, the length of preamble is the same as the length of postamble, and is N (e.g., 2, 3, 4, 5, 6, 7, 8) times the length of midamble. For example, the length of preamble is N (e.g., 2, 3, 4, 5, 6, 7, 8) times the length of postamble. For example, when one downlink signaling contains M midambles, the total length of the M midambles is less than or equal to the length of the preamble of the downlink signaling. In some embodiments, the length of the preamble / midamble / postamble is signaled. For example, a plurality of preamble and / or midamble and / or postamble length / sequence combinations are predefined, and one of them is signaled. In some embodiments, the length of the preamble can be at least one of: 32, 48, 64, 96, 128. In some embodiments, the length of the midamble can be at least one of: 8, 12, 16, 24, 32, 48, 64. In some embodiments, the length of the postamble can be at least one of: 12, 16, 24, 32, 48, 64, 96, 128. For example, a plurality of preamble and postamble length / sequence combinations are predefined, and the midamble sequence is fixed or there is no midamble. Each preamble length / sequence corresponds to one postamble length / sequence. For example, a plurality of preamble, midamble and postamble length / sequence combinations are predefined. Each preamble length / sequence corresponds to one postamble length / sequence, and one midamble length / sequence. For example, a plurality of preamble, postamble length / sequence combinations are predefined. Each preamble length / sequence corresponds to one midamble length / sequence. In some embodiments, at least one of the following is predefined: one or more preamble, postamble length / sequence combinations, one or more preamble, postamble and midamble length / sequence combinations, one or more preamble and midamble length / sequence combinations, one or more preamble length / sequences, one or more postamble length / sequences, one or more midamble length / sequences. One of the combinations or one of the sequences is signaled. In some embodiments, if each preamble length / sequence corresponds to one postamble length / sequence and one midamble length / sequence, but the downlink signaling does not require a midamble, then no midamble is inserted. That is, the use of a midamble is independent of whether a midamble length / sequence is indicated. In some embodiments, the postamble length / sequence is a first length / sequence when there is no midamble in the downlink signaling transmission, and a second length / sequence when there is a midamble in the downlink signaling transmission. That is, the postamble length / sequence is different depending on whether there is a midamble. The longer postamble after the absence of a midamble can enhance channel estimation / SFO estimation performance, and compensate for the absence of a midamble. In some embodiments, the postamble is a sequence of consecutive low / high levels, followed by high-low-high-low / low-high-low-high staggered levels / chips. The length of the consecutive low / high levels is greater than 2 chips Each level in the high-low-high-low staggered / low-high-low-high staggered levels is 1 chip. In some embodiments, there are M chips in total. For example, the postamble is a sequence of K1 consecutive low levels (K1 Os), followed by K2 high-low staggered (1010...) levels. For example, the postamble is a sequence of K1 consecutive high levels (K1 Is), followed by K2 low-high staggered (0101...) levels. In some embodiments, K1 can vary depending on the data end position. For example, if the data end is at the Pth chip in an OFDM symbol, then K1 = max(3, M-P). M is the M value corresponding to the data portion. Note that if the consecutive level is high, then the next level is low, and if the consecutive level is low, then the next level is high. In some embodiments, there are multiple midamble sequences, and the first level of the midamble sequence is determined based on the level before the midamble. The first level of the midamble is opposite to the level before the midamble. This facilitates the identification of the midamble. For example, there are two midamble sequences, and the first sequence is opposite to the second sequence in the 0, 1 positions. Position opposite means the position of 0 in the first sequence is 1 in the second sequence; the position of 1 in the first sequence is 0 in the second sequence. For example, 11110101, and 00001010. In some embodiments, the length of preamble / midamble / postamble is an integer multiple of the length of OFDM symbol. In some embodiments, the number of chips contained in midamble / postamble is a multiple of M. M is the value of M corresponding to the data / control part. In some embodiments, preamble / midamble / postamble ends at the last chip of an OFDM symbol. In one embodiment, the embodiment provides a scheme of the position and number of uplink preamble, midamble, postamble. Midamble, namely midamble sequence. In some embodiments, the number of midamble, and / or the presence of midamble, and / or the position of midamble is obtained by downlink control information. In some embodiments, the number of midamble is indicated in downlink control information, and TBS, and the position of midamble is determined according to TBS and the number of midamble. For example, TBS=A, and the number of midamble is B, then the uplink data is divided into (B+1) data subblocks, and midamble is inserted after each data subblock except the last data subblock. For example, TBS=A, and the number of midamble is B, then the uplink data is divided into (B+1) data subblocks, and midamble is inserted after each data subblock. No postamble is inserted. If A can be divided by B, then the sub-TBS of each data subblock is (A / B). If A cannot be divided by B, then the sub-TBS of mod(A / B) data subblocks is round up(A / B), and the sub-TBS of B-mod(A / B) data subblocks is round down(A / B). In some embodiments, the sub-TBS of the first mod(A / B) data subblocks is round up(A / B), and the sub-TBS of the last B-mod(A / B) data subblocks is round down(A / B). In some embodiments, the sub-TBS of the first B-mod(A / B) data sub-blocks is round down(A / B), and the sub-TBS of the last mod(A / B) data sub-blocks is round up(A / B). In some embodiments, a midamble is inserted every X chips. X is a positive integer greater than or equal to 100. X is a predefined value or a value indicated by signaling. For example, a plurality of candidate values of X can be configured, and one of them is indicated by signaling. The optional values of X are, for example: 128, 512, 256, etc. In some embodiments, a midamble is inserted every X data bits (before encoding). X is a positive integer greater than or equal to 100. X is a predefined value or a value indicated by signaling. For example, a plurality of candidate values of X can be configured, and one of them is indicated by signaling. In some embodiments, a midamble is inserted every X bits (after encoding of information bits). X is a positive integer greater than or equal to 100. X is a predefined value or a value indicated by signaling. For example, a plurality of candidate values of X can be configured, and one of them is indicated by signaling. In some embodiments, the insertion position of the midamble should be between two information bits, i.e., the midamble cannot be inserted between one information bit. For example, the information bits use Manchester encoding, and one information bit is encoded into two bits, then the midamble cannot be inserted between the two bits after encoding of one information bit. For another example, the information bits use Manchester encoding, and the repetition number is 3, then one information bit corresponds to 6 bits, and the midamble cannot be inserted between the 6 bits after encoding of one information bit. In some embodiments, the number and / or position of the midamble is obtained by downlink control information indication. A plurality of combinations of midamble number and / or position (also referred to as midamble insertion interval) are pre-configured / set, and one combination is obtained by downlink control information indication. For example, preset {midamble num=1, position=Y1 chips}, {midamble num=4, position=Y2 chips},..., control information indicates one of them. {midamble num=U, position=Y} indicates that a midamble is inserted every Y chips / OFDM symbols / bits / codewords of data, and a total of U midambles are inserted. For example, the maximum number of midambles is fixed (e.g., K), and the downlink control information indicates a position. It indicates that a midamble is inserted after every Y chips / OFDM symbols / bits / codewords of data. A total of K midambles are inserted at most. In some embodiments, at least one of the following is indicated in the D2R (device to reader) control information: whether a midamble is inserted, the number of midambles, whether a postamble is inserted, position information of the midamble insertion, D2R preamble length, D2R midamble length, D2R postamble length, uplink data TBS information. The position information of the midamble insertion can be an X value indicating that a midamble is inserted every X OFDM symbol number / chip number / slot number / minimum time interval number / bit number / codeword number. For example, a plurality of X values are predefined, and one of them is indicated. The device determines the number, position, etc. of the midamble according to the above information. The specific determination method is the same as the method in the above embodiments. In some embodiments, if the number of OFDM symbols / chips / slots / minimum time intervals / bits / codewords between the positions of the midamble and the postamble is less than a first threshold, the postamble is not sent (i.e., the postamble is not inserted). In some embodiments, if the number of OFDM symbols / chips / slots / minimum time intervals / bits / codewords between the positions of the midamble and the postamble is less than a first threshold, the corresponding midamble is not sent. Preamble, i.e., the second preamble sequence. In some embodiments, the preamble includes K short sequences, i.e., K discrete sequences. The K short sequences are spaced apart by X chips. Figure 7 is a schematic diagram of a second preamble according to an embodiment of the application. As shown in Figure 7, X chips are inserted between two adjacent short sequences. Two adjacent short sequences in the K short sequences are separated by Y OFDM symbols. That is, Y OFDM symbols are inserted between two adjacent short sequences. Two adjacent short sequences in the K short sequences are separated by Z bits. That is, Z bits of information are inserted between two adjacent short sequences. Two adjacent short sequences in the K short sequences are separated by N codewords. That is, N codeword information is inserted between two adjacent short sequences. X is a positive integer greater than or equal to 1. In some embodiments, X, Y, Z, N are values of M corresponding to the data part. In some embodiments, K is a positive integer greater than or equal to 2. For example, K = 2. The preamble includes two short sequences. In some embodiments, the K short sequences are the same sequence. In some embodiments, the K short sequences are different sequences. In some embodiments, the K short sequences have the same length. In some embodiments, the preamble includes one long sequence, i.e., a second sequence, and K short sequences, i.e., a third sequence. The long sequence is in front, and the K short sequences are after the long sequence. Adjacent sequences in the first sequence are separated by a set number of chips, OFDM symbols, bits, or codewords. For example, X chips / OFDM symbols / bits / codewords are inserted between two adjacent sequences. Figure 8 is a schematic diagram of another second preamble according to an embodiment of the application. As shown in Figure 8, M data chips are inserted between adjacent sequences in the long sequence and the short sequence. The X chips / OFDM symbols / bits / codewords are chips / OFDM symbols / bits / codewords of data. In some embodiments, the K short sequences are a subset of the long sequence. In some embodiments, the K short sequences are achieved by splitting the long sequence into K parts. In some embodiments, the length of the K short sequences is equal to the length of the long sequence. That is, K * short sequence length = long sequence length. K is a positive integer greater than or equal to 1. For example, the preamble includes one long sequence and one short sequence. The benefit of multiple short sequences is that CFO (Carrier Frequency Offset) estimation is facilitated. In some embodiments, the preamble of device type 2b comprises K short sequences. Alternatively, the preamble of device type 2b comprises 1 long sequence and K short sequences. That is, the above design is applicable to device type 2b. In some embodiments, the preamble of device type 1 and device type 2a comprises only 1 long sequence. In some embodiments, the long sequence of the preamble of all device types is the same sequence. In some embodiments, when the preamble comprises more than one sequence, the insertion position of the midamble is calculated according to the sequence position of the last preamble. Postamble, i.e. tail sequence. In some embodiments, the Postamble comprises P short sequences. The design of the preamble comprising multiple short sequences. In some embodiments, the Postamble of device type 2b comprises K short sequences. Alternatively, the Postamble of device type 2b comprises 1 long sequence and K short sequences. That is, the above design is applicable to device type 2b. In some embodiments, the long sequence is after the P short sequences. In some embodiments, the long sequence is before the P short sequences. In some embodiments, the design of the sequence in the Postamble can be the same as that of the preamble. In some embodiments, the last short sequence is an all-0 sequence. In some embodiments, the Postamble of device type 2b comprises K short sequences. Alternatively, the Postamble of device type 2b comprises 1 long sequence and K short sequences. That is, the above design is applicable to device type 2b. In some embodiments, the Postamble of device type 1 and device type 2a comprises only 1 long sequence. In some embodiments, the long sequence of the Postamble of all device types is the same sequence. In some embodiments, when the preamble includes more than one sequence, the position of the midamble is determined based on the start of the last sequence of the preamble. For example, the preamble includes two sequences with X chips of data between the two sequences, and a midamble is inserted every Y chips, then a midamble is inserted every Y chips after the last sequence of the preamble. In some embodiments, when the postamble includes more than one sequence, the position of the midamble is determined based on the start of the first sequence of the postamble. In some embodiments, when the preamble includes more than one sequence, and the position of the midamble is determined based on the start of the last sequence of the preamble. In one embodiment, the present embodiment provides a specific example of the first sequence: In some embodiments, the first sequence is achieved by Manchester encoding the fourth sequence and adding the fifth sequence. Manchester encoding is that bit 1 is encoded as '01', and bit 0 is encoded as '10'. The fourth sequence is at least one of: [-1, -1, 1, -1]; [1, 1, -1, 1]; [-1, 1, -1, -1]; [-1, 1, 1, 1]; [1, -1, -1, -1]; [1, -1, 1, 1]; [-1, -1, 1, -1, 1]; [1, 1, -1, 1, -1]; [-1, -1, -1, 1, -1]; [-1, 1, -1, -1, -1]; [1, -1, 1, 1, 1]; [1, 1, 1, -1, 1]; [-1, 1, -1, -1, -1, 1]; [-1, -1, -1, 1, -1, 1]; [1, 1, 1, -1, -1, 1]; [-1, -1, 1, 1, -1, 1]; [-1, 1, 1, 1, -1, 1]; [-1, 1, -1, -1, 1, 1, 1]; [1, -1, 1, 1, -1, -1, -1]; [-1, -1, -1, 1, 1, -1, 1]; [1, 1, 1, -1, -1, 1, -1]; [-1, -1, 1, 1, -1, 1, -1]; [1, 1, -1, -1, 1, -1, 1]; [-1, -1, 1, -1, 1, -1, -1, -1]; [1, 1, -1, 1, -1, 1, 1, 1]; [-1, 1, -1, 1, 1, -1, -1, -1]; [1, -1, 1, -1, -1, 1, 1, 1]; [-1, -1, -1, 1, -1, 1, 1, -1]; [-1, -1, -1, 1, 1, -1, 1, -1]. Note that 1 represents 1 and -1 represents 0. The fifth sequence is two chips identical to the last level of the fourth sequence. For example, the fourth sequence is [-1, -1, 1, -1] (i.e.

[0010] ), the encoding result is [10100110], and the two chips identical to the last level are

[0000] , so the first sequence is [1010011000]. In some embodiments, the first sequence is obtained by Manchester encoding the fourth sequence and adding the fifth sequence, and the fifth sequence is inserted before the second last bit of the encoding result of the fourth sequence. The fourth sequence is at least one of: [-1, -1, 1, -1]; [1, 1, -1, 1]; [-1, 1, -1, -1]; [-1, 1, 1, 1]; [1, -1, -1, -1]; [1, -1, 1, 1]; [-1,-1,1,1]; [1,1,-1,-1]; [-1,1,-1,-1,1]; [1,-1,1,1,-1]; [-1,-1,1,-1,-1]; [-1,1,1,-1,-1]; [1,-1,-1,1,1]; [1,1,-1,1,1]; [-1,1,-1,1,1,-1]; [1,-1,1,-1,-1,1]; [-1,1,-1,-1,-1,1]; [1,-1,1,1,1,-1]; [-1,-1,-1,1,-1,1]; [1,1,1,-1,1,-1]; [-1,-1,-1,1,-1,1,-1]; [1,1,1,-1,1,-1,1]; [-1,-1,1,-1,1,1,-1]; [-1,1,-1,-1,-1,-1,1]; [1,-1,1,1,1,1,-1]; [1,1,-1,1,-1,-1,1]; [-1,1,1,1,-1,1,-1,1]; [1,-1,-1,-1,1,-1,1,-1]; [-1,-1,1,-1,1,-1,-1,1]; [-1,1,-1,1,1,1,-1,1]; [1,-1,1,-1,-1,-1,1,-1]; [1,1,-1,1,-1,1,1,-1]. The fifth sequence is inserted before the second last position of the fourth sequence after encoding, and is two chips of the same level as the level before the insertion position. For example, the fourth sequence is [-1,-1,1,-1] (i.e.

[0010] ), after encoding, it is [10100110], and two chips of the same level as the third last level are

[0011] Therefore, the first sequence is [1010011110]. In some embodiments, the first sequence is obtained by Manchester encoding the fourth sequence and adding the fifth sequence, the fifth sequence is inserted after the fourth sequence after encoding, and the second sequence is fixed as 11. The fourth sequence is at least one of the following: [1,1,-1,1]; [-1,1,1,1]; [1,-1,1,1]; [-1,1,-1,-1]; [-1,-1,-1,1]; [1,-1,-1,1]; [-1,-1,1,-1,1]; [1,-1,1,1,1]; [1,1,1,-1,1]; [-1,1,-1,1,1]; [-1,1,-1,-1,-1]; [1,-1,-1,-1,1]; [-1,1,-1,-1,-1,1]; [-1,-1,-1,1,-1,1];[-1,-1,1,1,-1,1];[-1,1,1,1,-1,1];[-1,1,-1,1,1,1];[-1,1,-1,-1,1,1]; [-1,1,-1,-1,1,1,1];[-1,-1,-1,1,1,-1,1];[1,1,-1,-1,1,-1,1];[-1,1,-1,-1,-1,1,1];[1,-1,1,-1,-1,1,1];[-1,-1,-1,1,-1,-1,1];[1,1,-1,1,-1,1,1,1];[1,-1,1,-1,-1,1,1,1];[1,-1,1,-1,-1,1,1,1];[1,1,1,-1,-1,-1,1,1];[1,1,1,-1,-1,-1,1,1];[1,1,1,-1,-1,-1,1,-1,1];[1,1,1,-1,1,-1,-1,1];[1,1,1,-1,1,-1,-1,1]; For example, the fourth sequence is [-1,-1,1,-1] (i.e.)

[0010] ), after encoding, is [10100110], the two chips of the fifth sequence are

[0011] , then the first sequence is [1010011011]. In some embodiments, the first L1 chips and / or the last L2 chips of the first sequence are one or more sequences that violate Manchester encoding. The sequences that violate Manchester encoding are

[0011] ,

[0000] . In some embodiments, the first L1 chips and / or the last L2 chips of the first sequence are consecutive 1s or consecutive 0s, and L2 is a positive integer greater than or equal to 2. In one exemplary embodiment, this application provides a data transmission device that can be integrated on a first communication node. Figure 9 is a schematic diagram of the structure of a data transmission device provided in an embodiment of this application. As shown in Figure 9, the data transmission device includes: The first acquisition module 910 is configured to acquire first preamble information and first data. The first preamble information includes a start indication part and a clock acquisition part. The time domain resource position of the first data is after the first preamble information. The parsing module 920 is configured to parse the first data based on the first preamble information; The transmission module 930 is configured to transmit a first sequence and second data in response to the first data, wherein the first sequence is determined according to the target parameters. The data transmission device provided in this embodiment is used to implement the data transmission method shown in Figure 1. The implementation principle and technical effect of the data transmission device provided in this embodiment are similar to those of the data transmission method shown in Figure 1, and will not be repeated here. On the basis of the above-mentioned embodiments, variant embodiments of the above-mentioned embodiments are proposed, and it needs to be explained that, in order to make the description brief, only the differences from the above-mentioned embodiments are described in the variant embodiments. In one embodiment, the start indication part includes chips of two M values, and the two M values are in a multiple relationship. In one embodiment, the start indication part includes: chips of M being 1 and 2 respectively, or; chips of M being 1 and 3 respectively, or; chips of M being 2 and 4 respectively, or; chips of M being 1 and 4 respectively. In one embodiment, the start indication part is determined by the M value corresponding to the first data. In one embodiment, when the M value corresponding to the first data is a first M value, the start indication part is a first start indication sequence or a first chip length; when the M value corresponding to the first data is a second M value, the start indication part is a second start indication sequence or a second chip length; wherein the first chip length includes one or more; the second chip length includes one or more. In one embodiment, the data transmission device further comprises: The second acquisition module is configured to acquire control information, and the control information includes at least one of the following: command type indication information and power control indication information. In one embodiment, the command type indication information indicates the type of the first data or command that needs to be received. In one embodiment, the type corresponding to the first data includes at least one of the following: a first command, a second command, and a third command, the first command includes a paging command, the second command includes a downlink command after message 1, and the third command includes the remaining commands other than the first command and the second command or the third command includes a decrement command or a message 1 trigger command or a random access opportunity range command. Or, The first command includes a command that all unmonitored Internet of Things devices need to receive, the second command includes a command that devices receiving the first command need to receive, and the third command is a command that devices sending message 1 need to receive. Or, The first command includes a command that devices waiting for access need to receive, the second command includes a command that devices receiving the first command and waiting to send message 1 need to receive, and the third command includes a command that devices sending message 1 need to receive. Or, The first command comprises a command that the device needs to receive before accessing, and the third command comprises a command that the device needs to receive after sending the message 1. Or, The first command comprises a command that the device needs to receive before sending the message 1, and the third command comprises a command that the device needs to receive after sending the message 1. In one embodiment, the type corresponding to the first data comprises at least one of the following: paging-related signaling, inventory-related signaling, non-paging-related signaling, access-related signaling, signaling of specific device downlink data transmission, and downlink command after message 1. In one embodiment, the power control indication information indicates at least one of the following: whether the device performs signal amplification, or the device transmission power. In one embodiment, the setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information. In one embodiment, the setting information comprises one of the following: Whether the first type domain exists; Bit size of the first type domain. In one embodiment, the first type domain comprises at least one of the following: Internet of Things device identification indication information, code division multiplexing code indication information, frequency resource allocation information, frequency offset factor, frequency offset factor set, reader identification information, chip duration, modulation method, code rate, repetition number. In one embodiment, the second type domain comprises at least one of the following: Command type indication information, code division multiplexing enabling indication information, frequency division multiplexing enabling indication information, repetition enabling information, device type indication information. In one embodiment, the target parameter comprises one or more of the following: Transmission block size of uplink data, total number of bits of uplink data, number of bits of uplink data after encoding and / or repetition, transmission code rate of uplink data, transmission block size of uplink data sub-block, number of bits of uplink data sub-block, number of bits of uplink data sub-block after encoding and / or repetition, reader identification information, signaling indication information, first threshold value. In one embodiment, the signaling indication information indicates at least one of the following: index of the second preamble information, index of the intermediate sequence in the first sequence, index of the tail sequence in the first sequence, whether the intermediate sequence is used in the uplink data, interval of insertion of the intermediate sequence in the first sequence, whether the tail sequence is used in the uplink data, first threshold value, and number of intermediate sequences in the first sequence. In one embodiment, when the corresponding transmission length of the uplink data is greater than the first threshold, the number of inserted intermediate sequences is 3, when the corresponding transmission length of the uplink data is less than or equal to the first threshold and greater than the second threshold, the number of inserted intermediate sequences is 2, when the corresponding transmission length of the uplink data is less than or equal to the second threshold and greater than the third threshold, the number of inserted intermediate sequences is 1, and when the corresponding transmission length of the uplink data is less than or equal to the third threshold, the number of inserted intermediate sequences is 0, wherein the third threshold is less than the second threshold, and the second threshold is less than the first threshold; or, when the corresponding transmission length of the uplink data is greater than the first threshold, the number of inserted intermediate sequences is 2, when the corresponding transmission length of the uplink data is less than or equal to the first threshold and greater than the second threshold, the number of inserted intermediate sequences is 1, and when the corresponding transmission length of the uplink data is less than or equal to the second threshold, the number of inserted intermediate sequences is 0, wherein the second threshold is less than the first threshold; or, when the corresponding transmission length of the uplink data is greater than the first threshold, the number of inserted intermediate sequences is 1, and when the corresponding transmission length of the uplink data is less than or equal to the first threshold, the number of inserted intermediate sequences is 0. In an embodiment, the first sequence includes one or more of the following: second preamble information, intermediate sequences, and tail sequences; and the length relationship of the second preamble information, the intermediate sequences, and the tail sequences satisfies one of the following: the length of the second preamble information is greater than the length of the tail sequences, the length of the tail sequences is greater than the length of the intermediate sequences, or the length of the second preamble information is greater than the length of the tail sequences and the intermediate sequences, the length of the intermediate sequences is the same as the length of the tail sequences, or the length of the second preamble information is a first set multiple of the length of the tail sequences, and the length of the tail sequences is a second set multiple of the length of the intermediate sequences. In an embodiment, the association of the first sequence with the target parameter includes at least one of the following: the length of one or more first sequences is determined according to the target parameter; the position of one or more first sequences is determined according to the target parameter; the number of one or more first sequences is determined according to the target parameter; the presence or absence of one or more first sequences is determined according to the target parameter. In an embodiment, the data transmission method further includes: the sending module is configured to: if the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold value, the corresponding intermediate sequence or tail sequence is not sent; otherwise, the intermediate sequence and the tail sequence are both sent; or if the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits or the number of code words occupied by the data after the time domain resource position of the intermediate sequence is less than a fourth threshold value, the corresponding intermediate sequence and tail sequence are not sent; otherwise, the intermediate sequence and the tail sequence are both sent; or when the transmission length corresponding to the uplink data is less than a fifth threshold value, the corresponding intermediate sequence and tail sequence are not sent; when the transmission length corresponding to the uplink data is greater than the fifth threshold value and less than a sixth threshold value, the intermediate sequence or the tail sequence is sent; when the transmission length corresponding to the uplink data is greater than the sixth threshold value, the intermediate sequence and the tail sequence are both sent. In one embodiment, the first sequence includes K discrete sequences. In one embodiment, an interval of X chips is provided between two adjacent discrete sequences in the K discrete sequences, or an interval of Y transmission symbols is provided between two adjacent discrete sequences in the K discrete sequences, or an interval of Z bits is provided between two adjacent discrete sequences in the K discrete sequences, or an interval of N code words is provided between two adjacent discrete sequences in the K discrete sequences. In one embodiment, the first sequence includes a second sequence and K third sequences, and the length of the second sequence is greater than the length of the third sequence. In one embodiment, a set number of chips, transmission symbols, bits or code words is provided between two adjacent sequences in the first sequence. In one example embodiment, the present application provides a data transmission device, which can be integrated on a second communication node. FIG. 10 is a structural schematic diagram of another data transmission device provided by an embodiment of the present application; as described in FIG. 9, the data transmission device includes: the transmission module 1010 is configured to: transmit first preamble information and first data, the first preamble information includes a start indication part and a clock acquisition part, and the time domain resource position of the first data is after the first preamble information, and the first data is parsed based on the first preamble information; the acquisition module 1020 is configured to: acquire a first sequence and second data, the first sequence is determined according to a target parameter, and the first sequence and the second data are contents in response to the first data transmission. The data transmission apparatus provided in the embodiment is used for implementing the data transmission method of the embodiment shown in FIG. 2. The implementation principle and technical effects of the data transmission apparatus provided in the embodiment are similar to those of the data transmission method of the embodiment shown in FIG. 2, and will not be described here again. On the basis of the above-mentioned embodiments, variant embodiments of the above-mentioned embodiments are proposed. It should be noted that, in order to make the description brief, only the differences between the variant embodiments and the above-mentioned embodiments are described in the variant embodiments. In one embodiment, the start indication part comprises: M is 1 and 2 chips, respectively, or; M is 1 and 3 chips, respectively, or; M is 2 and 4 chips, respectively, or; M is 1 and 4 chips, respectively. In one embodiment, the start indication part is determined by the M value corresponding to the first data. In one embodiment, when the M value corresponding to the first data is a first M value, the start indication part is a first start indication sequence or a first chip length; when the M value corresponding to the first data is a second M value, the start indication part is a second start indication sequence or a second chip length; wherein the first chip length comprises one or more; the second chip length comprises one or more. In one embodiment, the data transmission apparatus further comprises an information transmission module, configured to: transmit control information, the control information comprising at least one of the following: command type indication information, power control indication information. In one embodiment, the command type indication information indicates the type of the first data or command that needs to be received. In one embodiment, the type corresponding to the first data comprises at least one of the following: a first command, a second command, and a third command. In one embodiment, the first command comprises a paging command, the second command comprises a downlink command after message 1, and the third command comprises the remaining commands other than the first command and the second command or the third command comprises a decrement command or a message 1 trigger command or a random access opportunity range command. or, the first command comprises a command that all unmonitored Internet of Things devices need to receive, the second command comprises a command that devices need to receive after receiving the first command, and the third command is a command that devices need to receive after sending message 1. or, The first command comprises a command that needs to be received by the device waiting for access, the second command comprises a command that needs to be received by the device waiting for sending the message 1 after receiving the first command, and the third command comprises a command that needs to be received by the device after sending the message 1. Alternatively, The first command comprises a command that needs to be received by the device waiting for access, and the third command comprises a command that needs to be received by the device after sending the message 1. Alternatively, The first command comprises a command that needs to be received by the device before sending the message 1, and the third command comprises a command that needs to be received by the device after sending the message 1. In one embodiment, the type of the downlink data comprises at least one of the following: paging-related signaling, inventory-related signaling, non-paging-related signaling, access-related signaling, signaling of downlink data transmission of a specific device, and downlink command after the message 1. In one embodiment, the power control indication information indicates at least one of the following: whether the device performs signal amplification, or the device transmission power. In one embodiment, the setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information. In one embodiment, the setting information comprises one of the following: Whether the first type domain exists; Bit size of the first type domain. In one embodiment, the first type domain comprises at least one of the following: Internet of Things device identification indication information, code division multiplexing code indication information, frequency resource allocation information, frequency offset factor, frequency offset factor set, reader identification information, chip duration, modulation mode, code rate, and repetition number. In one embodiment, the second type domain comprises at least one of the following: Command type indication information, code division multiplexing enabling indication information, frequency division multiplexing enabling indication information, repetition enabling information, and device type indication information. In one embodiment, the target parameter comprises one or more of the following: Transmission block size of uplink data, total number of bits of uplink data, number of bits of uplink data after encoding and / or repetition, transmission code rate of uplink data, transmission block size of uplink data sub-block, number of bits of uplink data sub-block, number of bits of uplink data sub-block after encoding and / or repetition, reader identification information, signaling indication information, and first threshold value. In an embodiment, the signaling indication information indicates at least one of: an index of the second preamble information, an index of the middle sequence in the first sequence, an index of the tail sequence in the first sequence, whether the middle sequence is used in the uplink data, an interval of insertion of the middle sequence in the first sequence, whether the tail sequence is used in the uplink data, a first threshold, and a number of the middle sequence in the first sequence. In an embodiment, When the transmission length corresponding to the uplink data is greater than the first threshold, the number of the inserted middle sequence is 3; when the transmission length corresponding to the uplink data is less than or equal to the first threshold and greater than a second threshold, the number of the inserted middle sequence is 2; when the transmission length corresponding to the uplink data is less than or equal to the second threshold and greater than a third threshold, the number of the inserted middle sequence is 1; and when the transmission length corresponding to the uplink data is less than or equal to the third threshold, the number of the inserted middle sequence is 0. The third threshold is less than the second threshold, and the second threshold is less than the first threshold; or, When the transmission length corresponding to the uplink data is greater than the first threshold, the number of the inserted middle sequence is 2; when the transmission length corresponding to the uplink data is less than or equal to the first threshold and greater than a second threshold, the number of the inserted middle sequence is 1; and when the transmission length corresponding to the uplink data is less than or equal to the second threshold, the number of the inserted middle sequence is 0. The second threshold is less than the first threshold; or, When the transmission length corresponding to the uplink data is greater than the first threshold, the number of the inserted middle sequence is 1; and when the transmission length corresponding to the uplink data is less than or equal to the first threshold, the number of the inserted middle sequence is 0. In an embodiment, the first sequence includes one or more of the following: the second preamble information, the middle sequence, and the tail sequence; and a length relationship of the second preamble information, the middle sequence, and the tail sequence satisfies one of the following: The length of the second preamble information is greater than the length of the tail sequence, the length of the tail sequence is greater than the length of the middle sequence, or The length of the second preamble information is greater than the length of the tail sequence and the length of the middle sequence, the length of the middle sequence is the same as the length of the tail sequence, or The length of the second preamble information is a first set multiple of the length of the tail sequence, and the length of the tail sequence is a second set multiple of the length of the middle sequence. In an embodiment, the first sequence is associated with a target parameter, and the association includes at least one of the following: The length of one or more of the first sequences is determined according to the target parameter; The position of one or more of the first sequences is determined according to the target parameter; The number of one or more of the first sequences is determined according to the target parameter; whether or not one or more of the first sequences is determined according to the target parameter. In one embodiment, the data transmission device further comprises a receiving module configured to: receive one or more of the intermediate sequence and the tail sequence. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of codewords occupied by the data after the time domain resource location of the intermediate sequence is less than a fourth threshold value, the corresponding intermediate sequence or tail sequence is not transmitted. When the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of codewords occupied by the data after the time domain resource location of the intermediate sequence is greater than or equal to the fourth threshold value, both the intermediate sequence and the tail sequence are received. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of codewords occupied by the data after the time domain resource location of the intermediate sequence is less than a fourth threshold value, neither the intermediate sequence nor the tail sequence is transmitted. If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of codewords occupied by the data after the time domain resource location of the intermediate sequence is greater than or equal to the fourth threshold value, both the intermediate sequence and the tail sequence are received. When the transmission length corresponding to the uplink data is less than a fifth threshold value, neither the intermediate sequence nor the tail sequence is transmitted. When the transmission length corresponding to the uplink data is greater than or equal to the fifth threshold value and less than a sixth threshold value, the intermediate sequence or the tail sequence is received. When the transmission length corresponding to the uplink data is greater than or equal to the sixth threshold value, both the intermediate sequence and the tail sequence are received. In one embodiment, the first sequence comprises K discrete sequences. In one embodiment, an interval between two adjacent discrete sequences in the K discrete sequences is X chips; or, an interval between two adjacent discrete sequences in the K discrete sequences is Y transmission symbols; or, an interval between two adjacent discrete sequences in the K discrete sequences is Z bits; or, an interval between two adjacent discrete sequences in the K discrete sequences is N codewords. In one embodiment, the first sequence comprises a second sequence and K third sequences, and a length of the second sequence is greater than a length of the third sequence. In one embodiment, an interval between two adjacent sequences in the second preamble information is a set number of chips, transmission symbols, bits, or codewords. In an example embodiment, the application also provides a first communication node, and FIG. 11 is a structural schematic diagram of a first communication node provided by an embodiment of the application; as shown in FIG. 11, the first communication node provided by the application includes one or more processors 111 and a storage device 112; the processor 111 in the first communication node can be one or more, and FIG. 11 takes one processor 111 as an example; the storage device 112 is configured to store one or more programs; the one or more programs are executed by the one or more processors 111, so that the one or more processors 111 implement the data transmission method as described in the embodiments of the application. The first communication node further includes a communication device 113, an input device 114, and an output device 115. The processor 111, the storage device 112, the communication device 113, the input device 114, and the output device 115 in the first communication node can be connected through a bus or other means, and FIG. 11 takes the connection through the bus as an example. The input device 114 can be used to receive input digital or character information, and generate key signal input related to user settings and function control of the first communication node. The output device 115 can include a display device such as a display screen. The communication device 113 can include a receiver and a transmitter. The communication device 113 is configured to perform information receiving and transmitting communication according to the control of the processor 111. The storage device 112 as a kind of computer readable storage medium can be configured to store software programs, computer executable programs, and modules, such as program instructions / modules (for example, the first acquisition module 910, the analysis module 920, and the transmission module 930 in the data transmission device) of the data transmission method described in the embodiments of the application. The storage device 112 can include a program storage area and a data storage area, wherein the program storage area can store an operating system, application programs required by at least one function; the data storage area can store data created according to the use of the first communication node, etc. In addition, the storage device 112 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some examples, the storage device 112 can further include a storage device remotely arranged with respect to the processor 111, and these remote storage devices can be connected to the first communication node through a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. In one example implementation, the embodiments of the present application also provide a second communication node, and FIG. 12 is a structural schematic diagram of a second communication node provided by the embodiments of the present application. As shown in FIG. 12, the second communication node provided by the embodiments of the present application includes one or more processors 121 and a storage device 122; the processor 121 in the second communication node can be one or more, and FIG. 12 takes one processor 121 as an example; the storage device 122 is configured to store one or more programs; the one or more programs are executed by the one or more processors 121, so that the one or more processors 121 implement the data transmission method as described in the embodiments of the present application. The second communication node further includes a communication device 123, an input device 124, and an output device 125. The processor 121, the storage device 122, the communication device 123, the input device 124, and the output device 125 in the second communication node can be connected through a bus or other means, and FIG. 12 takes the connection through the bus as an example. The input device 124 can be configured to receive input digital or character information, and generate key signal inputs related to user settings and function controls of the second communication node. The output device 125 can include a display device such as a display screen. The communication device 123 can include a receiver and a transmitter. The communication device 123 is configured to perform information receiving and transmitting communication under the control of the processor 121. The storage device 122, as a kind of computer readable storage medium, can be configured to store software programs, computer executable programs, and modules, such as program instructions / modules (for example, the transmission module 1010 and the acquisition module 1020 in the data transmission device) corresponding to the data transmission method described in the embodiments of the present application. The storage device 122 can include a program storage area and a data storage area, wherein the program storage area can store an operating system and application programs required by at least one function; the data storage area can store data created according to the use of the second communication node, etc. In addition, the storage device 122 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state memory device. In some examples, the storage device 122 can further include a storage device remotely arranged with respect to the processor 121, and these remote storage devices can be connected to the second communication node through a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. In an example embodiment, the application further provides a storage medium storing a computer program, the computer program being executed by a processor of a first communication node to implement the method provided by the application, or the computer program being executed by a processor of a second communication node to implement the method provided by the application. The storage medium stores a computer program, the computer program being executed by a processor to implement the data transmission method according to any of the example embodiments. The data transmission method applied to the first communication node includes: obtaining first preamble information and first data, the first preamble information including a start indication part and a clock acquisition part, and a time domain resource position of the first data being after the first preamble information; analyzing the first data based on the first preamble information; transmitting a first sequence and second data in response to the first data, the first sequence being determined according to a target parameter. The data transmission method applied to the second communication node includes: transmitting first preamble information and first data, the first preamble information including a start indication part and a clock acquisition part, and a time domain resource position of the first data being after the first preamble information, and the first data being analyzed based on the first preamble information; obtaining a first sequence and second data, the first sequence being determined according to a target parameter, and the first sequence and the second data being contents transmitted in response to the first data. The computer storage medium of the application can adopt any combination of one or more computer readable media. The computer readable medium can be a computer readable signal medium or a computer readable storage medium. The computer readable storage medium may, for example, be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination thereof. More specific examples (non-exhaustive list) of the computer readable storage medium include: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read only memory (ROM), an erasable programmable read only memory (EPROM), a flash memory, an optical fiber, a portable CD-ROM, an optical storage device, a magnetic storage device, or any suitable combination of the above. The computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or component. A computer readable signal medium can include a propagated data signal with computer executable code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal can take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium can be any computer readable medium that can be involved in The code can be transmitted in any form, including, but not limited to, radio frequency (RF) signals, digital signals, light, sound, or other media. The media can take a variety of forms, including, but not limited to, wire, cable, fiber optics, or any other suitable medium. Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). The specific embodiments described hereinabove are illustrative of specific embodiments of the present application and are not meant to be limiting of the present application. Those skilled in the art will appreciate that the term device encompasses any suitable type of wireless user equipment, such as a mobile phone, a portable data processing apparatus, a portable web browser, or a vehicle-mounted mobile station. Generally, the various embodiments of the present application can be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects can be implemented in hardware, while other aspects can be implemented in Embodiments of the application can be implemented by computer program instructions on a data processor of a mobile device, for example in processor entities, or by hardware, or by a combination of software and hardware. The computer program instructions can be assembly instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages. Any block diagrams of logical flows of the application can represent program steps, or logical operations, or a combination of program steps and logical operations. The computer program can be stored on a storage memory. The storage memory can be of any suitable type and can be implemented using any suitable data storage technology, such as, but not limited to, a random access memory (RAM), a read-only memory (ROM), an optical storage device, a magnetic storage device, and the like. The computer readable media can include non-transitory storage media. The data processor can be of any suitable type and can be implemented using any suitable data processing technology, such as, but not limited to, a general purpose computer, a microprocessor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA) and a processor based on multi-core processor architecture. The foregoing detailed description of the exemplary embodiments of the application has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the application to the precise form disclosed. Many modifications and variations are possible in light of this disclosure without departing from the scope of the disclosure.

Claims

1. A data transmission method, comprising: obtaining first preamble information and first data, the first preamble information comprising a start indication part and a clock acquisition part, and a time domain resource position of the first data being after the first preamble information; parsing the first data based on the first preamble information; transmitting a first sequence and second data in response to the first data, the first sequence being determined according to a target parameter.

2. The method of claim 1, wherein, The start indication part comprises chips of two M values, and the two M values are in a multiple relationship.

3. The method of claim 2, wherein, The start indication part comprises: chips of M values of 1 and 2, respectively, or chips of M values of 1 and 3, respectively, or chips of M values of 2 and 4, respectively, or chips of M values of 1 and 4, respectively.

4. The method of claim 1, wherein, The start indication part is determined by an M value corresponding to the first data. 5.The method of claim 1, wherein, when the M value corresponding to the first data is a first M value, the start indication part is a first start indication sequence or a first chip length; and when the M value corresponding to the first data is a second M value, the start indication part is a second start indication sequence or a second chip length; wherein the first chip length comprises one or more; and the second chip length comprises one or more. 6.The method of claim 1, further comprising: obtaining control information, the control information comprising at least one of: command type indication information, power control indication information.

7. The method of claim 6, wherein, The command type indication information indicates a type corresponding to the first data or command.

8. The method of claim 7, wherein, The type corresponding to the first data comprises at least one of: a first command, a second command, a third command, The first command comprises a paging command, the second command comprises a downlink command after message 1, and the third command comprises a remaining command other than the first command and the second command or the third command comprises a decreasing command or a message 1 trigger command or a random access occasion range command; or, The first command comprises a command that all unmonitored Internet of Things devices need to receive, the second command comprises a command that devices after receiving the first command need to receive, and the third command is a command that devices after sending message 1 need to receive; or, The first command comprises a command that devices waiting for access need to receive, the second command comprises a command that devices after receiving the first command and waiting to send message 1 need to receive, and the third command comprises a command that devices after sending message 1 need to receive; or, The first command comprises a command that devices waiting for access need to receive, and the third command comprises a command that devices after sending message 1 need to receive; or, The first command comprises a command that devices need to receive before sending message 1, and the third command comprises a command that devices need to receive after sending message 1.

9. The method of claim 7, wherein, The type corresponding to the first data comprises at least one of: paging related signaling, monitoring related signaling, non-paging related signaling, access related signaling, signaling of specific device downlink data transmission, and downlink command after message 1.

10. The method of claim 6, wherein, The power control indication information indicates at least one of: whether a device amplifies a signal, and a device transmission power.

11. The method of claim 6, wherein, The setting information of the first type domain in the control information is indicated by the indication information of the second type domain in the control information.

12. The method of claim 11, wherein, The setting information includes one of the following: Whether the first type domain exists; Bit size of the first type domain.

13. The method of claim 11, wherein, The first type domain includes at least one of the following: Internet of Things device identification indication information, code division multiplexing code indication information, frequency resource allocation information, frequency offset factor, frequency offset factor set, reader identification information, chip duration, modulation mode, code rate, repetition number.

14. The method of claim 11, wherein, The second type domain includes at least one of the following: Command type indication information, code division multiplexing enabling indication information, frequency division multiplexing enabling indication information, repetition enabling information, device type indication information.

15. The method of claim 1, wherein The target parameter includes at least one of the following: Transport block size of uplink data, total number of bits of uplink data, number of bits of uplink data after encoding and / or repetition, transmission code rate of uplink data, transport block size of uplink data sub-block, number of bits of uplink data sub-block, number of bits of uplink data sub-block after encoding and / or repetition, reader identification information, signaling indication information, first threshold value.

16. The method of claim 15, wherein, The signaling indication information indicates at least one of the following: index of second preamble information, index of intermediate sequence in the first sequence, index of tail sequence in the first sequence, whether intermediate sequence is used in uplink data, interval of insertion of intermediate sequence in the first sequence, whether tail sequence is used in uplink data, first threshold value, number of intermediate sequences in the first sequence.

17. The method of claim 15, wherein, When the transmission length corresponding to the uplink data is greater than the first threshold value, the number of inserted intermediate sequences is 3, when the transmission length corresponding to the uplink data is less than or equal to the first threshold value and greater than the second threshold value, the number of inserted intermediate sequences is 2, when the transmission length corresponding to the uplink data is less than or equal to the second threshold value and greater than the third threshold value, the number of inserted intermediate sequences is 1, when the transmission length corresponding to the uplink data is less than or equal to the third threshold value, the number of inserted intermediate sequences is 0, wherein the third threshold value is less than the second threshold value, and the second threshold value is less than the first threshold value; or When the transmission length corresponding to the uplink data is greater than the first threshold value, the number of inserted intermediate sequences is 2, when the transmission length corresponding to the uplink data is less than or equal to the first threshold value and greater than the second threshold value, the number of inserted intermediate sequences is 1, when the transmission length corresponding to the uplink data is less than or equal to the second threshold value, the number of inserted intermediate sequences is 0, wherein the second threshold value is less than the first threshold value; or When the transmission length corresponding to the uplink data is greater than the first threshold value, the number of inserted intermediate sequences is 1, when the transmission length corresponding to the uplink data is less than or equal to the first threshold value, the number of inserted intermediate sequences is 0.

18. The method of claim 1, wherein, The first sequence includes at least one of the following: second preamble information, intermediate sequence and tail sequence; the length relationship of the second preamble information, the intermediate sequence and the tail sequence satisfies one of the following: The length of the second preamble information is greater than the length of the tail sequence, the length of the tail sequence is greater than the length of the middle sequence, the length of the second preamble information is greater than the length of the tail sequence and the length of the middle sequence, the length of the middle sequence is the same as the length of the tail sequence, The length of the second preamble information is a first set multiple of the length of the tail sequence, and the length of the tail sequence is a second set multiple of the length of the middle sequence.

19. The method of claim 1, wherein, The first sequence is associated with a target parameter, including at least one of the following: The length of at least one first sequence is determined according to the target parameter; The position of at least one first sequence is determined according to the target parameter; The number of at least one first sequence is determined according to the target parameter; The presence or absence of at least one first sequence is determined according to the target parameter.

20. The method of claim 1, further comprising: If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the middle sequence is less than a fourth threshold value, the corresponding middle sequence or tail sequence is not transmitted; if the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the middle sequence is greater than or equal to the fourth threshold value, the middle sequence and the tail sequence are both transmitted; or, If the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the middle sequence is less than a fourth threshold value, the corresponding middle sequence and tail sequence are not transmitted; if the number of orthogonal frequency division multiplexing symbols, the number of chips, the number of time slots, the number of minimum time intervals, the number of bits, or the number of code words occupied by the data after the time domain resource position of the middle sequence is greater than or equal to the fourth threshold value, the middle sequence and the tail sequence are both transmitted; or, When the transmission length corresponding to the uplink data is less than a fifth threshold value, the corresponding middle sequence and tail sequence are not transmitted; when the transmission length corresponding to the uplink data is greater than or equal to the fifth threshold value and less than a sixth threshold value, the middle sequence or the tail sequence is transmitted; when the transmission length corresponding to the uplink data is greater than or equal to the sixth threshold value, the middle sequence and the tail sequence are both transmitted.

21. The method of claim 1, wherein, The first sequence includes K discrete sequences.

22. The method of claim 21, wherein, The interval between adjacent two discrete sequences in the K discrete sequences is X chips, or; The interval between adjacent two discrete sequences in the K discrete sequences is Y transmission symbols, or; The interval between adjacent two discrete sequences in the K discrete sequences is Z bits, or; The interval between adjacent two discrete sequences in the K discrete sequences is N code words.

23. The method of claim 1, wherein, The first sequence includes one second sequence and K third sequences, and the length of the second sequence is greater than the length of the third sequence.

24. The method of claim 23, wherein, The interval between adjacent sequences in the first sequence is a set number of chips, transmission symbols, bits, or code words.

25. A data transmission method, comprising: transmitting first preamble information and first data, the first preamble information comprising a start indication part and a clock acquisition part, and a time domain resource position of the first data being after the first preamble information, the first data being parsed based on the first preamble information; obtaining a first sequence and second data, the first sequence being determined according to a target parameter, and the first sequence and the second data being contents transmitted in response to the first data.

26. The method of claim 25, wherein, The start indication part comprises chips of two M values, the two M values being in a multiple relationship.

27. The method of claim 25, wherein, The first sequence comprises at least one of: second preamble information, an intermediate sequence and a tail sequence; and a length relationship of the second preamble information, the intermediate sequence and the tail sequence satisfies one of: a length of the second preamble information is greater than a length of the tail sequence, and the length of the tail sequence is greater than a length of the intermediate sequence, a length of the second preamble information is greater than lengths of the tail sequence and the intermediate sequence, and the intermediate sequence has a same length as the tail sequence, a length of the second preamble information is a first set multiple of a length of the tail sequence, and the length of the tail sequence is a second set multiple of a length of the intermediate sequence. 28.A first communication node, comprising: at least one processor; a storage device configured to store at least one program; when the at least one program is executed by the at least one processor, the at least one processor implements the method according to any one of claims 1-24. 29.A second communication node, comprising: at least one processor; a storage device configured to store at least one program; when the at least one program is executed by the at least one processor, the at least one processor implements the method according to any one of claims 25-27. 30.A storage medium, the storage medium storing a computer program, when the computer program is executed by a processor of a first communication node, the computer program implements the method according to any one of claims 1-24, or when the computer program is executed by a processor of a second communication node, the computer program implements the method according to any one of claims 25-27.

Images