A satellite random access system based on transmission mode and transmission system

Abstract

The present invention discloses a satellite ad-hoc access system based on a transmission mode and a transmission system, which relates to the field of satellite measurement and control technology. The main purpose is to realize the autonomous transmission and automated, intelligent access of telemetry and remote control data and high-speed data between a satellite constellation and a ground measurement and control network. The main technical solution of the present invention is as follows: the satellite physical layer channel includes a satellite downlink channel and a satellite uplink channel. The satellite downlink channel includes a downlink ad-hoc access channel, a downlink traditional telemetry channel, and a downlink dedicated channel. The ad-hoc access channel transmits access application information, satellite heartbeat information, and long data stream telemetry information. The downlink traditional telemetry channel transmits telemetry data that complies with standard protocols. The downlink dedicated channel transmits high-speed remote sensing data. The satellite uplink channel includes a broadcast channel, a traditional remote control channel, and an uplink dedicated channel. The uplink broadcast channel transmits application response information and broadcast remote control information, and the uplink dedicated channel transmits high-speed uplink data.

Description

Technical Field

[0001] The invention belongs to the technical field of satellite measurement and control, and relates to a satellite random access system based on a transmission mode and a transmission system. Background Art

[0002] In existing technologies, satellite tracking and control (TT&C) is typically performed according to pre-arranged plans. This requires coordinating the resources, configuration, and available time of the ground-based tracking and control network. This involves numerous manual operations and inter-agency coordination and communication, resulting in time-consuming and inefficient operations. This significantly restricts the rapid improvement of TT&C data transmission capabilities. With the development of the aerospace industry, especially the rapid growth of microsatellites in recent years, the number of satellites in orbit continues to increase, with a single constellation comprising thousands or even tens of thousands of satellites. If existing TT&C data transmission technologies are used, they will be unable to meet the TT&C data transmission needs of future mega-constellations and large numbers of satellites, posing an urgent challenge. Summary of the Invention

[0003] In view of the above problems, the present invention proposes a physical layer channel transmission mode and transmission system for a satellite random access system, the main purpose of which is to realize the autonomous transmission, intelligent access and automatic setting of parameters of telemetry data, remote control data and high-speed data between the satellite constellation and the ground measurement and control network.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides a physical layer channel transmission mode of a satellite tracking and control random access system, including a satellite downlink physical layer channel transmission mode and a satellite uplink physical layer channel transmission mode, specifically:

[0006] Satellite downlink physical layer channel transmission modes include: random access channel transmission mode, traditional telemetry channel transmission mode, and high-speed data dedicated channel transmission mode. Among them, the random access channel transmits access application information, satellite "heartbeat" information and long data stream telemetry information, the downlink traditional telemetry channel transmits telemetry data that complies with the standard protocol, and the downlink dedicated channel transmits high-speed remote sensing data.

[0007] The satellite uplink physical layer channel transmission modes include: broadcast channel transmission mode, traditional remote control channel transmission mode, and high-speed data dedicated channel transmission mode. Among them, the uplink broadcast channel transmits application response information and broadcast remote control information, the uplink traditional remote control channel transmits remote control data that complies with the standard protocol, and the uplink dedicated channel transmits high-speed injection data.

[0008] Secondly, the satellite selects a satellite access channel transmission mode based on access requirements and attribute information of the data to be transmitted; selects a transmission system of a downlink physical channel based on the satellite access channel transmission mode; and determines at least one of the modulation mode, coding mode, and spread spectrum mode of the data to be transmitted based on the downlink physical channel transmission system.

[0009] On the third aspect, the ground measurement and control network selects the uplink channel transmission mode according to the attributes of the application information and the attribute information of the data to be transmitted; selects the transmission system of the uplink physical channel according to the uplink physical channel transmission mode; determines at least one of the encoding mode, modulation mode, and spread spectrum mode of the data to be transmitted according to the transmission system of the uplink physical channel; determines the attributes of the response information, the target transmission mode, and the target data to be sent according to the attributes of the access information of the satellite downlink channel.

[0010] By means of the above technical solution, the present invention provides a physical layer channel transmission mode, device, and system for a satellite random access system, which can realize the automatic setting of transmission plans, transmission modes, and transmission mechanisms between satellites and ground measurement and control networks. In the present invention, the application received by the ground measurement and control network is an access application request initiated autonomously by the satellite when the satellite needs to send data to be transmitted. That is, there is no need to use a manually formulated transmission plan, that is, the access application request can be initiated to the ground measurement and control network at any time. After the ground measurement and control network receives the access application request, it first determines whether the data to be transmitted by the satellite can be sent to the satellite based on the current transmission resource status and the attribute information of the data to be transmitted carried in the application request. If it can be sent, it matches multiple transmission modes and transmission mechanisms for the data to be transmitted, and writes these multiple transmission modes and transmission mechanisms into response information and broadcasts it to the satellite. The satellite processes the response information of the uplink broadcast channel and selects one or more target transmission modes and transmission mechanisms from the multiple transmission modes and transmission mechanisms. Finally, based on the target transmission modes and transmission mechanisms, the target data to be transmitted is transmitted to the ground measurement and control network.

[0011] The present invention utilizes a ground-based measurement and control network to roughly screen multiple transmission modes and transmission schemes. The satellite then determines the final target transmission mode and transmission scheme from these multiple transmission modes and transmission schemes. Through collaboration between the ground-based measurement and control network and the satellite, the target transmission mode and transmission scheme in the transmission plan are determined, enabling data transmission between the satellite and the ground-based measurement and control network. This invention eliminates the manual process of developing transmission plans and setting transmission modes, reducing labor costs and adapting to scenarios where tens of thousands of satellites need to transmit data.

[0012] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0014] Figure 1 A flow chart of a physical layer downlink-uplink channel transmission mode of a satellite random access system proposed in an embodiment of the present invention is shown;

[0015] Figure 2 A flow chart of a downlink physical layer channel transmission mode of a satellite random access system proposed in an embodiment of the present invention is shown;

[0016] Figure 3 A flow chart showing another downlink physical layer channel transmission mode of a satellite random access system proposed in an embodiment of the present invention is shown;

[0017] Figure 4 A flow chart of an uplink physical layer channel transmission mode of a satellite random access system proposed in an embodiment of the present invention is shown;

[0018] Figure 5 A schematic structural diagram of a transmission device for a ground portion of a satellite random access system proposed in an embodiment of the present invention is shown;

[0019] Figure 6 A schematic structural diagram of a transmission device for the ground portion of another satellite random access system proposed in an embodiment of the present invention is shown;

[0020] Figure 7 A schematic structural diagram of a transmission device for an on-board portion of a satellite random access system proposed in an embodiment of the present invention is shown;

[0021] Figure 8 A schematic structural diagram of a transmission device for an on-board portion of another satellite random access system proposed in an embodiment of the present invention is shown;

[0022] Figure 9 The present invention shows a satellite-to-ground link application-response transmission flow chart of a satellite random access system proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0024] In existing technology, satellites must transmit data to the ground-based tracking and control network according to a transmission plan. These plans are manually created. Ground personnel develop a transmission plan for each satellite based on the ground-based tracking and control network's transmission resources and the data the satellite will transmit. With the development of the space industry, the number of satellites in orbit is increasing. In the future, mega-constellations and clusters will emerge, some with potentially tens of thousands of satellites. This large number of satellites necessitates the manual development of tens of thousands of tracking and control transmission plans, making such a large number of plans impractical to create manually.

[0025] Based on the above situation, the inventors believe that the purpose of automatically formulating a transmission plan can be achieved through coordination between the ground measurement and control network and the satellite. Specifically, when a satellite needs to transmit data, it can actively initiate an access application request to the ground measurement and control network. After the ground measurement and control network receives the access application request, it automatically formulates a transmission plan for the satellite based on the current transmission resource status and the attributes of the access application, and sends the formulated transmission plan to the satellite in the application response. The satellite transmits the data to be transmitted to the ground measurement and control network based on the application response information. This access application does not require a manually formulated transmission plan to realize autonomous data transmission between the satellite and the ground measurement and control network. This access application-application response working mode reduces labor costs and also meets the needs of future giant constellation data transmission. The specific implementation steps of the embodiment of the present invention are as follows: Figure 1 Shown, including:

[0026] 101. The satellite selects an access channel transmission mode based on access requirements and attribute information of the data to be transmitted.

[0027] Attribute information characterizes the type of data to be transmitted. For example, attribute information can be used to determine whether the data is burst data, continuous data, periodic heartbeat data, traditional telemetry data, high-speed data, etc. It can also be used to determine the importance of the data. An access request is an autonomous request sent by a satellite to establish a connection with a ground control station when a data transmission is needed. Only after the ground control network authenticates the access request can the satellite send the data to the corresponding ground control station.

[0028] When many satellites send access requests, in order for the ground measurement and control network to determine which satellite sends the access request, the access request needs to carry the satellite identifier. In addition, if the ground measurement and control network has idle transmission resources for data transmission, in order to match the transmission mode to the data to be transmitted, the access request also needs to carry the attribute information of the data to be transmitted.

[0029] It should be noted that this solution is applicable to systems with multiple ground tracking and control stations and multiple satellites. A ground tracking and control network can receive access application requests from multiple satellites. When the ground tracking and control network receives an access application request from a certain satellite, if the ground tracking and control station does not receive the application data from the satellite, it will not respond to the access application request. The satellite will continue to operate in orbit and continue to send access application requests until the ground tracking and control network responds or the number of applications reaches the maximum limit.

[0030] 102. Select a downlink physical channel transmission system according to the access channel transmission mode.

[0031] Among them, the access channel transmission modes include: short data burst mode, heartbeat data periodic transmission mode, long data stream transmission mode, traditional telemetry data transmission mode, and high-speed data continuous transmission mode; according to the transmission mode, the downlink physical channel transmission system is selected or matched, and the transmission system includes: one or more of the modulation methods, the coding methods, and the spread spectrum methods.

[0032] When the downlink access channel transmission mode is the short data burst mode, the downlink access channel transmission system is the low-order modulation mode, the coding mode is the CA-Polar coding mode, and the code length in the spread spectrum mode is one or two of the three code lengths: the short code (code length 1023), the short code (code length 2047), and the long code (256 times of 1023).

[0033] When the downlink access channel transmission mode is the heartbeat data periodic transmission mode, the modulation system is the low-order modulation mode, the coding mode is the CA-Polar coding mode, and the code length in the spread spectrum mode is one or two of the three code lengths: short code (code length 1023), short code (code length 2047), and long code (256 times of 1023).

[0034] When the downlink access channel transmission mode is the long data stream continuous transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the CA-Polar coding mode or the LDPC coding mode, and the code length in the spread spectrum mode is one or two of the three code lengths: short code (code length 1023), short code (code length 2047), and long code (256 times of 1023).

[0035] When the downlink transmission channel transmission mode is the traditional telemetry data transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the CA-Polar coding mode or the LDPC coding mode, and the code length in the spread spectrum mode is one or two of the three code lengths: short code (code length 1023), short code (code length 2047), and long code (256 times of 1023).

[0036] When the downlink transmission channel transmission mode is the high-speed data continuous transmission mode, the modulation mode is the high-order modulation mode or the low-order modulation mode, and the coding mode is the LDPC coding mode.

[0037] 103. Determine, according to the downlink physical channel transmission system, a coding mode, a modulation mode, and a spreading mode of at least one downlink channel for data to be transmitted.

[0038] The downlink channel modulation mode includes: low-order modulation and high-order modulation. Low-order modulation modes include BPSK (Binary Phase Shift Keying), π / 2BPSK (default), QPSK (Quadrature Phase Shift Keying), UQPSK (Unbalanced Quadrature Phase Shift Keying), OQPSK (Offset-QPSK), with OQPSK as the default. UQPSK modulation can be used for satellite ranging. High-order modulation modes include 8PSK (8Phase Shift Keying), 16APSK (16Amplitude-Phase Shift Keying), and 32APSK.

[0039] Furthermore, the downlink channel coding mode includes: CA-Polar (CRC-Aided Polar, cyclic redundancy check assisted polar code) coding mode, and the coding rate is optional in the range of 1 / 3 to 5 / 6; LDPC (Low Density Parity Check, low-density parity check) coding mode, and the coding rate is optional in the range of 1 / 2 to 9 / 10.

[0040] The downlink scrambling method complies with the relevant standards of CCSDS (Consultative Committee for Space Data Systems) and ETSI (European Telecommunications Standards Institute). For the CA-Polar coding method, the scrambling function of the present invention is embodied in the CA-Polar coding method.

[0041] The downlink interleaving coding method is a matrix method or a random interleaving method. The matrix method is row writing and column reading or column writing and row reading. The low-order modulation method generally does not use interleaving technology. The high-order modulation method in the present invention uses scrambling technology and interleaving technology to achieve randomization of the data stream to improve the error performance of the receiving end.

[0042] The information rate of the downlink random access channel of the present invention is as follows: the low-speed information rate is selectable in the range of 1 to 150 kbit / s, the default value is selectable in the range of 2 kbit / s, 4 kbit / s, 8 kbit / s, and 16 kbit / s, and the high-speed information rate is selectable in the range of 1 to 300 Mbit / s.

[0043] Furthermore, the downlink spread spectrum mode is a direct sequence spread spectrum mode, including: short code and long code. The short code lengths are 1023 and 2047 respectively, and the long code length is 256 times the short code length of 1023, which is used for satellite ranging. The short code length can select either of the two code lengths (optional mode) and take into account the satellite ranging requirements. In this embodiment, the number of spread spectrum codes is not less than 32, the code chip rate is selected in the range of 1 to 16 Mc / s, the spread spectrum bandwidth is selected in the range of 2 to 32 MHz, and the carrier roll-off factor is selected in the range of 0.2 to 1.0.

[0044] 104. The ground measurement and control network selects an uplink channel transmission mode according to the uplink channel attributes and the attributes of the data to be transmitted.

[0045] Among them, the uplink channel attribute information is used to characterize the channel type of uplink data to be transmitted, such as a broadcast channel, a traditional remote control channel and a high-speed data dedicated channel; the uplink data to be transmitted attribute information is used to characterize the type information of the data to be transmitted, and to determine whether the data to be transmitted is response data or remote control data, broadcast remote control data or traditional remote control data, low-rate data or high-speed data, etc.; it is also possible to determine, based on the channel type information, whether the uplink channel is a burst transmission mode or a continuous transmission mode, a low-rate mode or a high-speed mode, a broadcast transmission mode or a dedicated channel transmission mode, etc.

[0046] When many satellites receive uplink information, in order for the satellites to determine which ground measurement and control station sends the response information or remote control information, the response information and remote control information need to carry the ground measurement and control station identification. In order to match the transmission mode and transmission system for the data to be transmitted, the uplink information also needs to carry the attribute information of the data to be transmitted.

[0047] It should be noted that this solution is applicable to systems with multiple ground tracking and control stations and multiple satellites. A ground tracking and control station network can send response information and remote control information to multiple satellites. If the satellite does not receive the response information from the ground, the satellite will wait for a random time and then send an access application request to the ground until it receives the response information from the ground or the specified time is exceeded.

[0048] 105. Select an uplink channel transmission system according to the uplink channel transmission mode.

[0049] The uplink channel transmission modes include: broadcast transmission mode, traditional remote control transmission mode and high-speed data dedicated channel transmission mode; wherein, the broadcast transmission mode includes: application response, broadcast remote control and application response + broadcast remote control composite three sub-channel modes; the traditional remote control transmission mode is a burst mode and a continuous transmission mode, and the high-speed data dedicated channel transmission mode is a continuous transmission mode; according to the transmission mode or the transmission mode, the uplink physical channel transmission system is selected or matched, and the transmission system includes: one or more of the modulation methods, the coding methods, and the spread spectrum methods.

[0050] Among them, when the uplink channel transmission mode is the broadcast transmission mode, the transmission system of the uplink broadcast channel is the low-order modulation mode, the coding mode is the LDPC coding mode or the CA-Polar coding mode, and the spread spectrum mode is any one of the two short code lengths (1023 or 2047), and the long code length is 256 times of 1023; the data type of the uplink broadcast channel includes only response data, only broadcast remote control data, and response data + broadcast remote control data; when the uplink broadcast data type is the response data, the uplink channel transmission mode is the broadcast transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the CA-Polar coding mode or the LDPC coding mode, and the spread spectrum mode is any one of the two code lengths (1023 or 2047); when the uplink broadcast data type is the broadcast remote control data, the uplink broadcast channel transmission mode is the broadcast transmission mode, the modulation mode is the low-order modulation mode, and the coding mode is the LDP C coding mode or CA-Polar coding mode, the spread spectrum mode is any one of the two short code lengths (1023 or 2047); when the broadcast data type is the response data + broadcast remote control data, the uplink broadcast channel transmission mode is the long data stream continuous broadcast transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the LDPC coding mode or CA-Polar coding mode, and the spread spectrum mode is any one of the two short code lengths (1023 or 2047); when the uplink channel transmission mode is the traditional remote control data transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the LDPC coding mode, and the code length in the spread spectrum mode is any one of the two code lengths (1023 or 2047); when the uplink channel transmission mode is the dedicated channel transmission mode and the high-speed long data stream continuous transmission mode, the modulation mode is the high-order modulation mode or the low-order modulation mode, and the coding mode is the LDPC coding mode.

[0051] 106. Determine, according to the uplink physical channel transmission system, a coding mode, a modulation mode, and a spreading mode of at least one uplink channel of data to be transmitted.

[0052] Among them, the uplink channel modulation modes include: low-order modulation and high-order modulation. Among them, the low-order modulation modes include BPSK, π / 2BPSK (default), QPSK, UQPSK, OQPSK (default), and UQPSK modulation can be used for satellite ranging; high-order modulation modes include 8PSK, 16APSK and 32APSK.

[0053] Uplink channel coding methods include: CA-Polar coding method, with a coding rate optional in the range of 1 / 3 to 5 / 6; LDPC coding method, with a coding rate optional in the range of 1 / 2 to 9 / 10; downlink scrambling code complies with CCSDS and ETSI relevant standards; downlink interleaving coding method is matrix interleaving method or random interleaving method, and the matrix interleaving method is row writing and column reading or column writing and row reading.

[0054] The uplink broadcast channel information rate of the present invention is as follows: the low-speed information rate is selectable in the range of 1 to 150 kbit / s, the default value is selectable in the range of 2 kbit / s, 4 kbit / s, 8 kbit / s, and 16 kbit / s, and the high-speed information rate is selectable in the range of 1 to 10 Mbit / s.

[0055] Furthermore, the uplink spread spectrum mode is a direct sequence spread spectrum mode, including: short code and long code. The short code lengths are 1023 and 2047 respectively, and the long code length is 256 times the short code length of 1023, which is used for satellite ranging. The short code length can select either of the two code lengths, taking into account the satellite ranging requirements. In this embodiment, the number of spread spectrum codes is not less than 32, the code chip rate is selected in the range of 1 to 16 Mc / s, the spread spectrum bandwidth is selected in the range of 2 to 32 MHz, and the carrier roll-off factor is selected in the range of 0.2 to 1.0.

[0056] Further, an optional embodiment of the present invention is in the above Figure 1 Based on the above, a detailed description of the steps for determining at least one transmission mode is given, and the specific steps are as follows: Figure 2 Shown, including:

[0057] 201. The satellite selects at least one transmission channel according to current access requirements.

[0058] The transmission channels include at least one channel for transmitting satellite access request information, heartbeat information, a low-speed long data stream access channel, a traditional telemetry channel, and a high-speed data dedicated channel. Because the satellites in the embodiment of the present invention are autonomous and access the ground measurement and control network on an ad hoc basis, the access channels in the embodiment of the present invention are also referred to as ad hoc access channels.

[0059] 202. Determine the data type of the data to be transmitted based on the attribute information.

[0060] Attribute information includes data type, data rate, and data name. The data type can be one of five types: short data, heartbeat data, long data stream, traditional telemetry data, and high-speed data. Different data types correspond to one or more transmission modes.

[0061] 203. Match one or more transmission modes, modulation modes, coding modes, and spread spectrum modes to the data to be transmitted according to the data type and transmission channel.

[0062] The transmission mode is one of a short data burst mode, a heartbeat mode, a continuous transmission mode, a traditional telemetry transmission mode, and a high-speed data transmission mode. Furthermore, in an embodiment of the present invention, the short data burst mode may be an ad hoc access mode. When a satellite sends an access request, it may be based on the ad hoc access mode.

[0063] Specifically, 1. Ad hoc access mode is an on-demand random burst mode. For example, if a satellite does not receive an access request response from the ground measurement and control network within a certain time window, it can resend the access request based on a random delay mechanism. 2. Heartbeat mode is a mode that transmits data intermittently and regularly. This mode can be used to transmit satellite health data and critical telemetry data. 3. Continuous transmission mode is used to transmit long data streams of telemetry data acquired by satellite payloads. 4. Traditional telemetry transmission mode can be used to transmit telemetry data that complies with the CCSDS standard. 5. High-speed data transmission mode is used to transmit high-speed data acquired by satellite payloads, such as remote sensing data.

[0064] In embodiments of the present invention, in addition to matching the transmission mode to the data to be transmitted, the operating mechanism for transmitting the data to be transmitted can also be matched. Taking the operating mechanism corresponding to the random access channel as an example, the operating mechanism can include a single burst, multiple bursts at random intervals, retransmission with confirmation from the ground measurement and control network, periodic bursts, and continuous transmission.

[0065] Specifically, 1. Single burst: the satellite will send the transmitted data when the target transmission data needs to be sent, and it will only be sent once; 2. Multiple bursts at random intervals: the satellite will send the target transmission data when it needs to be sent, and the number of repeated transmissions is 1 to n times, the number n can be set as required, and the time interval is a random number; 3. Retransmission if there is no response from the ground measurement and control network: the satellite will send the target transmission data, and the ground measurement and control network will send an uplink confirmation message after receiving the data. If the satellite does not receive the confirmation message, it will resend it at a certain interval until it receives the confirmation message or the maximum number of retransmissions is reached; 4. Periodic transmission: burst once every cycle; 5. Continuous transmission: within a certain period of time, the satellite continuously sends target transmission data to the ground.

[0066] In the embodiment of the present invention, it is also necessary to determine the transmission system according to the data type and the transmission channel. The transmission system includes modulation mode, coding mode, scrambling mode, interleaving mode, spread spectrum mode, information rate, etc.

[0067] Specifically, 1. Modulation mode: Data transmitted on the downlink random access channel and the uplink broadcast channel can use low-order modulation mode, including BPSK, π / 2BPSK, QPSK, UQPSK, and OQPSK. The default is π / 2BPSK or OQPSK. Satellite ranging data can use UQPSK modulation mode. High-speed data for downlink and uplink can adopt high-order modulation methods, which include 8PSK, 16APSK and 32APSK; 2. Coding method: Data transmitted in the downlink random access channel adopts CA-Polar coding method, and the coding rate is optional from 1 / 3 to 5 / 6. The uplink broadcast channel adopts LDPC coding method, and the coding rate is optional from 1 / 2 to 9 / 10; 3. Scrambling and interleaving: The target transmission data of high-order modulation has a scrambling function, and the scrambling code complies with the relevant standards of CCSDS and ETSI. The interleaving adopts matrix interleaving method, row writing and column reading or column writing and row reading, or random interleaving method; 4. Spread spectrum method: In order to increase the capacity of the access channel and reduce the carrier power spectral density, the embodiment of the present invention adopts direct sequence spread spectrum. The specific parameters can be that the number of spread spectrum codes is not less than 16, the length of two spread spectrum codes, and taking into account the satellite ranging requirements, the code chip rate is selected in the range of 1 to 16 Mc / s, and the spread spectrum bandwidth is selected in the range of 2 to 32 MHz.

[0068] 5. Information rate: The low-speed information rate is selectable in the range of 1 to 150 kbit / s. The default value is selectable from 2 kbit / s, 4 kbit / s, 8 kbit / s, and 16 kbit / s. The high-speed information rate is selectable in the range of 1 to 300 Mbit / s.

[0069] The embodiment of the present invention can determine multiple transmission systems according to the data type and transmission channel, and can match one or more transmission modes, modulation methods, coding methods, spread spectrum methods, etc. according to the data type and each transmission channel.

[0070] For example, when the downlink data type is periodic heartbeat data, the transmission mode is determined to be a short data periodic burst transmission mode, the modulation mode is a low-order modulation mode, the coding mode is a CA-Polar coding mode, and the spread spectrum mode is a direct sequence spread spectrum mode; when the downlink data type is a long data stream, the transmission mode is determined to be a continuous transmission mode, the modulation mode is a low-order modulation mode, the coding mode is an LDPC coding mode, and the spread spectrum mode is a direct sequence spread spectrum mode.

[0071] 204. Arrange and combine one or more transmission modes, modulation modes, coding modes, and spread spectrum modes to obtain at least one data processing mode.

[0072] The data processing method includes transmission mode and transmission system, and the transmission system at least includes modulation method, coding method, scrambling method, interleaving method, information rate, spread spectrum method and other contents.

[0073] 205. Generate at least one transmission mode by utilizing a combination of a data processing method and a transmission channel.

[0074] It should be noted that within a transmission mode, there is only one transmission channel, transmission mode, modulation scheme, coding scheme, and spread spectrum scheme. The ground measurement and control network generates multiple transmission modes, but the number of each element in a transmission mode is 1. For example, the satellite generates three transmission modes: transmission mode A, transmission mode B, and transmission mode C. Transmission mode A includes ad-hoc access mode, π / 2BPSK, and CA-Polar coding; transmission mode B includes ad-hoc access channel, heartbeat mode, π / 2BPSK, and CA-Polar coding; and transmission mode C includes high-speed data channel, continuous transmission mode, 8PSK, and LDPC coding.

[0075] 206. Determine a data clock synchronization method based on one or more transmission modes.

[0076] In embodiments of the present invention, in addition to matching the transmission mode of the data to be transmitted, the synchronization mode of the data to be transmitted can also be matched. Synchronous modes include asynchronous and synchronous. Access request information can use an asynchronous mode, while satellite health data can use a synchronous mode. The synchronous mode can be synchronized with the satellite payload clock or the uplink channel clock. The synchronization mode is configurable, and the default mode is synchronized with the satellite payload time.

[0077] In this embodiment of the present invention, all data processing modes are determined for the data to be transmitted, and ultimately all transmission modes are obtained by combining the data processing modes and the transmission channels. This embodiment of the present invention can provide multiple transmission modes to a satellite, allowing the satellite to select the optimal target transmission mode based on its own circumstances. The satellite autonomously selects the target transmission mode from among the multiple transmission modes, taking the satellite's own circumstances into consideration in determining the target transmission mode, thereby improving the rationality of the target transmission mode determination.

[0078] For a more detailed explanation Figure 2 Corresponding embodiment, the present invention provides another embodiment of satellite tracking and control random access channel transmission mode, the specific implementation steps are as follows Figure 3 Shown, including:

[0079] 301. Acquire attribute information based on satellite access requirements and transmission instructions of data to be transmitted.

[0080] The attribute information at least includes data type, data size, and data name. For the specific description of attribute information, please refer to Figure 1 The 101 steps are not repeated here.

[0081] When the satellite has data to transmit to the ground measurement and control network, the satellite will trigger a transmission instruction. According to the transmission instruction, it will obtain the attribute information of the data to be transmitted so as to determine the transmission mode using the attribute information.

[0082] 302. Utilize the attribute information of the application response carrying at least one transmission mode fed back by the ground measurement and control network.

[0083] Among them, the attribute information of the application response includes at least the ground segment identification, application confirmation, transmission mode, synchronization method, etc. The working status of the ground measurement and control network and the working status of the access channel are judged based on these attribute information.

[0084] 303. Generate an original access application based on the attribute information and obtain an access application request.

[0085] Among them, the original access application is a pre-set access application template. When there is data to be transmitted, the original access application can be generated directly based on the data type, data size, data name and other information in the attribute information of the data to be transmitted, so that the access application request can be obtained quickly.

[0086] 304. Determine, according to the access application request, to use the random access channel burst mode for transmission.

[0087] In order to realize the automatic formulation of transmission plans, the satellite in the embodiment of the present invention is autonomously and randomly connected to the ground measurement and control network. That is to say, when the satellite needs to transmit data, the satellite autonomously initiates an access application request, uses the access application request to establish a connection with the ground measurement and control network, and automatically transmits the data to be transmitted after the connection is established.

[0088] 305. Continue to determine the type of data to be transmitted based on the attribute information and determine the channel transmission mode.

[0089] The embodiment of the present invention can also determine the type of data to be transmitted based on its attribute information, such as whether it is low-speed short data or low-speed long data stream, traditional telemetry data or high-speed remote sensing data. Short data can be transmitted using a heartbeat mode, while long data streams can be transmitted using a continuous transmission mode. Different transmission modes can be distinguished to further refine the transmitted data.

[0090] 306. If the data is short and low-speed, determine to use the heartbeat mode of the random access channel for transmission.

[0091] Among them, the short data, such as key telemetry data, has a very small amount of data, and there is a certain time interval between each short data burst. If the continuous transmission mode is used, it will inevitably occupy some transmission resources, but in fact the transmission resources are not fully utilized. Therefore, part of the key telemetry data to be transmitted can be transmitted using the heartbeat mode, which not only can effectively transmit data, but also saves transmission resources.

[0092] It should be noted that the heartbeat period of the heartbeat mode can be set, for example, the default is once per minute.

[0093] 307. If the data is a low-speed long data stream, determine to use the continuous transmission mode of the random access channel for transmission.

[0094] Low-speed long data stream data can be transmitted using a random access channel. During the transmission of the long data stream data, heartbeat mode data is not sent. After the long data stream data transmission is completed, the sending of heartbeat mode data can be automatically restored.

[0095] 308. If it is traditional telemetry data, determine to use the traditional telemetry channel mode for transmission.

[0096] In the embodiment of the present invention, traditional telemetry data is transmitted through a traditional telemetry channel continuous transmission mode and a traditional telemetry system.

[0097] 309. If it is high-speed data, determine to use a dedicated channel mode for transmission.

[0098] In the embodiment of the present invention, downlink high-speed data, such as remote sensing data, is transmitted through a dedicated channel.

[0099] 310. Determine a target transmission mode for data to be transmitted based on at least one transmission mode.

[0100] In an embodiment of the present invention, the satellite can receive transmission mode information sent by the ground measurement and control network or the transmission mode stored in the satellite itself through uplink, extract all transmission modes, and select any one transmission mode as the target transmission mode from these transmission modes. One or more target transmission modes can also be selected based on the current situation of the satellite itself and / or the attribute information of the data to be transmitted.

[0101] For example, when the data to be transmitted is long data stream data, the continuous transmission mode can be selected as the target transmission mode for transmitting the long data stream data among multiple transmission modes; when the data to be transmitted is short data stream data, the transmission mode containing the heartbeat mode can be selected as the target transmission mode for transmitting the short data stream data, etc.

[0102] 311. Process the data to be transmitted based on the target transmission mode to obtain target transmission data.

[0103] The data to be transmitted is processed according to the corresponding transmission mode, transmission system, etc. in the target transmission mode to obtain target transmission data, so that the data to be transmitted can be transmitted through the transmission channel in the target transmission mode.

[0104] 312. Use the target transmission mode to transmit target transmission data to the ground measurement and control network.

[0105] In an embodiment of the present invention, after a transmission instruction is triggered, attribute information of the data to be transmitted is obtained and written directly into a pre-set original access request to obtain an access request. Since the original access request is a pre-set fixed template, an access request instruction can be quickly generated after the transmission instruction is triggered, and the access request can be transmitted using a random access channel. Furthermore, in an embodiment of the present invention, the type of the data to be transmitted is determined based on the attribute information of the data to be transmitted, including whether it is low-speed short data, low-speed long data stream data, traditional telemetry data, or high-speed data. If so, a target transmission mode for the data to be transmitted is determined based on at least one transmission mode. The data to be transmitted is then processed based on the target transmission mode to obtain target transmission data, which is then transmitted to the ground measurement and control network using the target transmission mode.

[0106] Accordingly, the embodiments of the present invention also include an uplink channel, that is, a channel for sending uplink data from the ground measurement and control network to the satellite. The uplink channel may include a broadcast channel, a traditional remote control channel, and an uplink high-speed data dedicated channel, wherein the broadcast channel also includes 3 sub-channel modes, namely, a response (sub) channel mode, a broadcast remote control (sub) channel mode, and a response channel + broadcast remote control (sub) channel mode. For example, when the ground measurement and control network needs to feed back an application response to the satellite, the broadcast channel can be used to transmit the response. The following will introduce the improvements made by the present invention on the basis of the existing technology with respect to the uplink channel. The specific implementation steps are as follows: Figure 4 Shown, including:

[0107] 401. Obtain access application attribute information based on the random access application information received by the ground measurement and control network.

[0108] The attribute information at least includes data type, data size, and data name. For the specific description of attribute information, please refer to Figure 1 The 101 steps are not repeated here.

[0109] In this embodiment of the present invention, uplink channels include broadcast channels (including response channels, broadcast-type remote control channels, and response-plus-broadcast remote control channels), traditional remote control channels, and dedicated high-speed data channels. For example, in this embodiment of the present invention, remote control data can be transmitted using both broadcast channels and traditional remote control channels. Furthermore, if remote control data is transmitted using a broadcast channel, this embodiment of the present invention can also concatenate the remote control data and the request response and send them together to the satellite via the broadcast channel.

[0110] In an embodiment of the present invention, the specific transmission modes of the uplink channel can be the following five: 1. Only application response data mode; 2. Only broadcast remote control data mode; 3. A mode in which application response data and broadcast remote control data are multiplexed into one data stream for broadcasting; 4. Traditional remote control mode; 5. High-speed data transmission mode: used for ground measurement and control network to send high-speed uplink data to satellites.

[0111] 402. Based on the obtained access application attribute information, the ground measurement and control network generates application response data of at least one transmission mode.

[0112] The transmission mode is selected based on the attribute information. For the specific implementation method, please refer to the above Figure 2 Steps 202 to 205 are not described in detail here.

[0113] 403. Determine, based on the application response data, to transmit the response data to be transmitted using an uplink broadcast channel mode.

[0114] 404. Continue to determine the type of data to be transmitted based on the uplink data attribute information and determine the channel transmission mode.

[0115] 405. If the data is broadcast remote control data, determine to transmit the broadcast remote control data using a broadcast channel mode.

[0116] 406. If the data is response+broadcast type remote control composite data, determine to transmit the composite data using the broadcast channel mode.

[0117] 407. If the data is traditional remote control data, determine to use the traditional remote control channel mode to transmit the traditional remote control data.

[0118] 408. If it is high-speed injection data, determine to transmit the high-speed injection data using a high-speed channel mode.

[0119] 409. Determine a target transmission mode for the data to be transmitted according to at least one transmission mode.

[0120] In the embodiment of the present invention, a transmission mode is selected as the target transmission mode according to any one of the transmission modes, and one or more target transmission modes may also be selected according to attribute information of the data to be transmitted.

[0121] 410. Process the data to be transmitted based on the target transmission mode to obtain target transmission data.

[0122] The data to be transmitted is processed according to the corresponding transmission mode, transmission system, etc. in the target transmission mode, so that the data to be transmitted can be transmitted through the target transmission mode and transmission channel.

[0123] 411. Target transmission data is transmitted to the satellite using the target transmission mode.

[0124] In this embodiment, when a ground-based tracking and control station receives an access request, it matches multiple transmission modes to the data to be transmitted based on the attribute information, generates a request response, and feeds these multiple transmission modes and the request response information back to the satellite for selection. This embodiment of the present invention automatically formulates the transmission modes in the transmission plan through collaboration between the satellite and the ground-based tracking and control network. This eliminates the need for manual transmission plan creation, reduces labor costs, and enables automatic transmission plan setup.

[0125] Furthermore, as a response to the above Figure 1-2 The implementation of the mode embodiment shown in the figure, the embodiment of the present invention provides a device for transmitting satellite measurement and control data, which is applied to the ground measurement and control network, and is used to realize the automatic setting of the transmission plan between the satellite and the ground measurement and control network, and adapts to the data transmission needs of tens of thousands of satellites. The embodiment of this device corresponds to the aforementioned mode embodiment. For the sake of ease of reading, this embodiment will no longer repeat the details of the aforementioned mode embodiment one by one, but it should be clear that the device in this embodiment can correspond to all the contents of the aforementioned mode embodiment. Specifically, Figure 5 As shown, the device includes:

[0126] The receiving unit 51 is configured to receive an access application request sent by a satellite and carrying attribute information of data to be transmitted;

[0127] The judging unit 52 is configured to judge whether to respond to the access application request received by the receiving unit 51 according to the application information;

[0128] A determining unit 53 is configured to determine at least one transmission mode for the data to be transmitted based on the current transmission resource status and attribute information when the determining unit 52 determines that the result is yes;

[0129] a sending unit 54 configured to send a request response carrying at least one transmission mode determined by the determining unit 53, so that the satellite determines a target transmission mode and target transmission data based on the at least one transmission mode;

[0130] The receiving unit 55 is configured to receive target transmission data transmitted by the satellite in a target transmission mode, where the target transmission mode is determined according to the application response sent by the sending unit 54 .

[0131] Further, such as Figure 6 As shown, the determining unit 53 includes:

[0132] A selection module 531 is configured to select at least one transmission channel according to current transmission requirements;

[0133] Determining module 532, for determining the data type of the data to be transmitted based on the attribute information;

[0134] a matching module 533 for matching one or more transmission modes, modulation schemes, coding schemes, and spread spectrum schemes to the data to be transmitted according to the data type determined by the determination module 532 and the transmission channel selected by the selection module 531;

[0135] Permutation and combination 534 is used to permutate and combine one or more transmission modes, modulation modes, coding modes, and spread spectrum modes determined by the matching module 533 to obtain at least one data processing mode;

[0136] The generating module 535 is configured to generate at least one transmission mode by combining the data processing method obtained by the permutation and combination 534 and the transmission channel selected by the selecting module 531 .

[0137] Furthermore, as a response to the above Figure 3-4 The implementation of the mode embodiment shown in the figure, the embodiment of the present invention provides a device for transmitting satellite measurement and control data, which is applied to satellites, and is used to realize the automatic setting of the transmission plan between satellites and ground measurement and control networks, and adapts to the data transmission needs of tens of thousands of satellites. The embodiment of this device corresponds to the aforementioned mode embodiment. For the sake of ease of reading, this embodiment will no longer repeat the details of the aforementioned mode embodiment one by one, but it should be clear that the device in this embodiment can correspond to all the contents of the aforementioned mode embodiment. Specifically, Figure 7 As shown, the device includes:

[0138] A forming unit 61 is configured to generate an access application request carrying attribute information of data to be transmitted;

[0139] The receiving unit 62 is configured to receive the access application request generated by the forming unit 61 and obtain an access application of at least one transmission mode;

[0140] A first determining unit 63 is configured to determine a target transmission mode for the data to be transmitted according to the at least one transmission mode obtained by the receiving unit 62;

[0141] an obtaining unit 64 configured to process the data to be transmitted based on the target transmission mode determined by the determining unit 63 to obtain target transmission data;

[0142] The transmission unit 65 is used to transmit the target transmission data obtained by the unit 64 to the ground measurement and control network using the target transmission mode.

[0143] Further, such as Figure 8 As shown, the forming unit 61 includes:

[0144] An acquisition module 611 is configured to acquire attribute information based on a transmission instruction of data to be transmitted;

[0145] Obtaining module 612, configured to write the attribute information obtained by obtaining module 611 into the original access application to obtain an access application request;

[0146] A module 613 is formed, which is configured to send the access application request obtained by the module 612 by using the first transmission channel.

[0147] Further, such as Figure 8 As shown, the device also includes:

[0148] The judgment unit 66 is used to judge whether the data to be transmitted is a short data stream or a long data stream, whether it is telemetry data of an access channel or traditional telemetry data, and whether it is downlink high-speed telemetry data or uplink high-speed injection data based on the attribute information;

[0149] The second determination unit 67 is used to determine whether the long data stream data of unit 66 is transmitted using a transmission mode including a continuous transmission mode, to determine whether the short data is transmitted using a transmission mode including a heartbeat mode, to determine whether the telemetry data is transmitted using a long data stream transmission mode, to determine whether the telemetry data is transmitted using a traditional telemetry transmission mode, and to determine whether the high-speed data is transmitted using a dedicated transmission mode.

[0150] Furthermore, the embodiment of the present invention also provides a satellite tracking and control random access system, which includes at least one satellite and at least one ground tracking and control network. The specific interaction process between the satellite and the ground tracking and control network is as follows: Figure 9 Shown, including:

[0151] 701. The satellite sends an access application request carrying attribute information.

[0152] The attribute information specifically refers to the attribute information of the data to be transmitted. When data transmission is required, the satellite writes the attribute information of the data to be transmitted into an access application request and sends the access application request so that one of the many ground stations can respond to the access application request.

[0153] 702. The ground measurement and control network determines whether to respond.

[0154] After receiving the access application request, the ground measurement and control network determines whether to respond based on the authentication information and attribute information. If the authentication is successful, step 703 is executed; otherwise, no response is made.

[0155] 703. The ground measurement and control network determines the transmission mode.

[0156] The ground measurement and control network determines at least one transmission mode according to the attribute information of the received data to be transmitted and the authentication pass information.

[0157] 704. The ground measurement and control network feeds back the request response information carrying the transmission mode and attributes to the satellite.

[0158] The ground measurement and control network writes the at least one transmission mode into the application response and feeds back the application response information to the corresponding satellite.

[0159] 705. The satellite determines the target transmission mode and target transmission data.

[0160] After receiving the response information, the satellite extracts the at least one transmission mode from the response information, determines the target transmission mode according to the transmission mode, and then processes the data to be transmitted using the target transmission mode to obtain the target transmission data that can be transmitted.

[0161] 706. The satellite uses the target transmission mode to transmit target transmission data to the ground measurement and control network.

[0162] The satellite uses the transmission channel in the target transmission mode to transmit target transmission data to the ground measurement and control network.

[0163] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0164] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned transmission mode embodiments and will not be repeated here.

[0165] The algorithm and display provided herein are not inherently related to any particular computer, virtual system or other device. Various general-purpose systems can also be used together with the teachings based on this. According to the above description, it is obvious that the structure required for constructing this type of system. In addition, the present invention is not directed to any specific programming language. It should be understood that various programming languages ​​can be utilized to realize the content of the present invention described herein, and the above description of specific languages ​​is for the purpose of disclosing the best mode of the present invention.

[0166] The above are merely embodiments of the present invention and are not intended to limit the present invention. It will be apparent to those skilled in the art that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of the present invention.

Claims

1. A satellite random access system based on transmission mode and transmission system, characterized in that: The physical layer channel of the satellite random access system includes: Satellite downlink channel and satellite uplink channel, The satellite downlink channel includes a downlink random access channel, a downlink traditional telemetry channel and a downlink dedicated channel. The random access channel transmits access application information, satellite heartbeat information and long data stream telemetry information. The traditional telemetry channel transmits telemetry data that complies with the standard protocol. The downlink dedicated channel transmits high-speed data. The satellite uplink channel includes a broadcast channel, a traditional remote control channel, and an uplink dedicated channel. The uplink broadcast channel transmits application response information and broadcast remote control information. The uplink traditional remote control channel transmits remote control data that complies with a standard protocol. The uplink dedicated channel transmits high-speed data. The ground measurement and control network determines the attributes of the response information, the target transmission mode, and the target data to be sent based on the attributes of the access information sent by the satellite. The transmission mode and transmission system of the physical layer channel also include: the working mechanism and synchronization method of the satellite random access system, as well as the modulation method, coding method, interleaving method, scrambling method, and spread spectrum method of the downlink physical channel and the uplink physical channel. The mode, mechanism, and method are used to achieve clock synchronization of the satellite downlink channel and transmission of downlink and uplink target data to be transmitted.

2. The system according to claim 1, wherein: The system further comprises: The satellite is used to select the access channel transmission mode or the dedicated channel transmission mode based on the access requirements and the attribute information of the data to be transmitted.

3. The system according to claim 2, characterized in that The system further includes: the satellite is used to determine at least one of the modulation mode, the coding mode, the interleaving mode, the scrambling mode, and the spread spectrum system of the data to be transmitted according to the attributes of the downlink data.

4. The system according to claim 1, wherein: The system further comprises: The ground measurement and control network is used to select the transmission mode of the uplink broadcast channel or the transmission mode of the dedicated channel based on the access application information and the attribute information of the data to be transmitted.

5. The system according to claim 4, characterized in that The system further includes: a ground measurement and control network for determining at least one of the modulation mode, the coding mode, and the spread spectrum system of the data to be transmitted according to the attributes of the uplink data.

6. The system according to claim 5, characterized in that The broadcast channel types of the system include at least an application response sub-channel, a broadcast remote control sub-channel, and an application response and broadcast remote control composite sub-channel.

7. The system according to claim 1, wherein: The system also includes: a satellite or ground measurement and control network used to arrange and combine one or more of the transmission modes, the modulation methods, the coding methods, and the spread spectrum methods to obtain at least one data processing method, and use the combination of the data processing method and the transmission channel to generate at least one transmission mode and a transmission system.

8. The system according to claim 7, characterized in that The downlink access channel data processing mode of the transmission channel includes a transmission mode and a transmission system, wherein the transmission system includes at least a modulation mode, a coding mode, and a spread spectrum mode. At least one data processing mode is determined based on the attribute information and at least one of the transmission channels, specifically for: Determining the type of downlink data to be transmitted based on downlink data attributes and data rate, wherein the type of downlink data to be transmitted is burst data, long data stream data, traditional telemetry data, or high-speed data; According to the downlink transmission channel, one or more of the transmission modes, the modulation modes, the coding modes, and the spread spectrum modes are matched to the data to be transmitted, wherein the transmission mode is one of the burst mode, the heartbeat mode, the continuous transmission mode, the traditional telemetry mode, and the high-speed data transmission mode; the modulation mode is one of the low-order modulation mode and the high-order modulation mode; the coding mode is one of the CA-Polar coding mode and the LDPC coding mode; the code length in the spread spectrum mode is a short code with a code length of 1023, a short code with a code length of 2047, and a long code with a code length of 256 times that of 1023, and any one or two of the three code lengths are selected.

9. The system according to claim 7, wherein: According to the uplink broadcast channel data processing mode of the transmission channel, including the data type and the transmission channel, matching one or more of the transmission mode, the modulation mode, the coding mode, and the spread spectrum mode to the data to be transmitted, specifically for: When the data type is response data, determining that the transmission mode is the response data broadcast transmission mode, the modulation mode is a low-order modulation mode, the coding mode is an LDPC coding mode or a CA-Polar coding mode, and the spread spectrum mode is selected from a short code with a code length of 1023, a short code with a code length of 2047, and a long code with a code length 256 times that of 1023, or any two of the three code lengths; When the data type is broadcast remote control data, determining that the transmission mode is a broadcast remote control broadcast transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the CA-Polar coding mode or the LDPC coding mode, and the code length in the spread spectrum mode is any one or two of the three code lengths; When the data type is composite data of a request response and a broadcast remote control, determining that the transmission mode is a composite data mode, the modulation mode is the low-order modulation mode, the coding mode is the CA-Polar coding mode or the LDPC coding mode, and the code length in the spread spectrum mode is any one or two of the three code lengths; When the data type is traditional remote control data, determining that the transmission mode is a burst mode or a continuous transmission mode, the modulation mode is the low-order modulation mode, the coding mode is the LDPC coding mode or the CA-Polar coding mode or other remote control coding mode, and the code length in the spread spectrum mode is any one or two of the three code lengths; When the data type is high-speed data, the transmission mode is determined to be a long data stream continuous transmission mode, the modulation mode is the low-order modulation mode or the high-order modulation mode, and the coding mode is the LDPC coding mode.

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