Compact feedback method, system and related device in satellite communication system

Abstract

The present application discloses a compact feedback method, system, and related apparatus in a satellite communication system. The method adds a type of compact feedback frame to a full-format feedback frame. The header of the compact feedback frame compresses the data in the header of the full-format feedback frame to improve the transmission efficiency of the outbound link in the satellite communication system.

Description

Technical Field

[0001] The present application relates to the field of satellite communications, and in particular to a compact feedback method, system, and related devices in a satellite communication system. Background Art

[0002] The Beidou satellite navigation system is a major infrastructure integrating positioning, timing, and communications. The Beidou short message service (BMS) distinguishes it from other global navigation systems, such as the US GPS, Russia's GLONASS, and Europe's GALILEO. It is particularly suitable for communication in areas such as oceans, deserts, grasslands, and uninhabited areas where mobile communications are not available, cannot be reached, or where communications systems are disrupted. The Beidou-3 satellite's short message system has upgraded its short message technology. To address the specific characteristics of civilian services and equipment, a communication protocol designed specifically for the Beidou short message service requires it.

[0003] Currently, in the Beidou short message service (BDS) communication system, the capacity of the outbound link, through which Beidou network devices transmit data to terminals, is limited by the system's design. The current capacity of each beam in the outbound link is 2 kbit / s, and even with good downlink channel quality, it's only 4 kbit / s. In a Beidou short message system supporting 18 beams, the total capacity of the entire system is only 40 kbit / s at best. Because the current BDS communication system lacks a separate control channel, all users share the outbound link, requiring high frame header overhead to schedule outbound resources for each user. After receiving a general data frame from a terminal, Beidou network devices must respond with an ACK frame on the outbound link. Feedback frames, such as ACK frames, contain only 4 bits of data. The large header overhead limits the number of feedback frames that can be accommodated on the outbound link, leading to the problem of not being able to respond to all terminals in the Beidou communication system simultaneously.

[0004] Therefore, how to improve the feedback efficiency of the feedback frame of the outbound link has become a difficult problem that needs to be solved urgently in the communication system of the Beidou short message service. Summary of the Invention

[0005] The present application provides a compact feedback method, system and related devices in a satellite communication system, which compresses the data amount in the frame header of a feedback frame in a complete format to obtain a feedback frame in a compact format, thereby improving the transmission efficiency of the outbound link.

[0006] In a first aspect, the present application provides a compact feedback method in a Beidou communication system, comprising: a terminal sends N satellite link control layer protocol data units (SLC PDUs) to a Beidou network device, where N is a positive integer, and the N SLC PDUs include a first SLC PDU, wherein the frame header of the first SLC PDU includes a first user identification (ID) field and an acknowledgment mode enable (AMenable) field, the first user ID field being used to indicate the device identification of the terminal, and the AM enable field being used to indicate the acknowledgment mode supported by the terminal at the satellite link control (SLC) layer. When the value of the AM enable field is used to indicate that the terminal supports the compact Cpack acknowledgment mode, the terminal receives a first compact Cpack feedback frame sent by the Beidou network device, the first Cpack feedback frame being used to indicate the reception status of the Beidou network device for the N SLC PDUs; wherein the first Cpack feedback frame includes a first user compact identification (CID) field, the first user CID field being used to indicate the compact device identification of the terminal, and the data length of the first user CID field being less than the data length of the first user ID field.

[0007] The present application provides a compact transmission method for a Beidou communication system, which adds a type of compact feedback frame to the full-format feedback frame. The frame header of the compact feedback frame compresses the data in the frame header of the full-format feedback frame to improve the transmission efficiency of the outbound link in the Beidou communication system.

[0008] In one possible implementation, the method also includes: when the value of the AM enable field is used to indicate that the terminal supports the complete Apack confirmation mode, the terminal receives a first complete Apack feedback frame sent by the Beidou network device, and the first Apack feedback frame is used to indicate the reception status of the Beidou network device for the N SLC PDUs; wherein, the frame header of the first Apack feedback frame includes a second user ID field, and the second user ID field is used to indicate the device identification of the terminal, and the value of the second user ID field is the same as the value of the first user ID field.

[0009] In a possible implementation, the frame header of the first Apack feedback frame further includes a first frame type field, where the first frame type field is used to indicate that the frame type of the first Apack feedback frame is an integrity confirmation identifier Apack ACK frame or an Apack receipt frame.

[0010] In a possible implementation, the frame header of the first Apack feedback frame further includes a start identification field, wherein the start identification field is located at the starting position in the frame header of the first Apack feedback frame, and the start identification field is used to identify the starting position of the first Apack feedback frame.

[0011] In one possible implementation, the frame header of the first Cpack feedback frame includes a second frame type field and a first frame length field, the value of the second frame type field is used to indicate that the frame type of the first Cpack feedback frame is a flexible feedback frame, and the first frame length field is used to indicate the total data length of the first user CID field and feedback information in the first Cpack feedback frame.

[0012] In one possible implementation, the frame header of the first Cpack feedback frame includes a third frame type field and a first frame subtype field, the value of the third frame type field is used to indicate that the frame type of the first Cpack feedback frame is a compact frame, and the value of the first frame subtype field is used to indicate that the frame subtype of the first Cpack feedback frame is a compact confirmation identifier Cpack ACK frame or a Cpack receipt frame.

[0013] In a possible implementation, the frame header of the first Cpack feedback frame includes a fourth frame type field, and a value of the fourth frame type field is used to indicate that the frame type of the first Cpack feedback frame is a Cpack ACK frame or a Cpack receipt frame.

[0014] In a possible implementation, the data length of the start identifier field is the same as the data length of the first user CID field.

[0015] In one possible implementation, the data length of the start identification field is a first length; wherein, when the data length of the specified portion of data in the first user ID field is the first length and is different from the value of the start identification field, the value of the first user CID field is the specified portion of data in the first user ID field; when the data length of the specified portion of data in the first user ID field is the same as the value of the start identification field, the value of the first user CID field is the sum of the specified portion of data in the first user ID field and a preset value.

[0016] In a possible implementation, the terminal receives a first compact Cpack feedback frame sent by the Beidou network device, specifically including: the terminal receives a first physical frame sent by the Beidou network device; and the terminal parses the first Cpack feedback frame from the first physical frame.

[0017] In the second aspect, the present application provides another compact feedback method in a Beidou communication system, including: a Beidou network device receives M SLC PDUs sent by a terminal, M is a positive integer, and the M SLC PDUs include a first SLC PDU, wherein the frame header of the first SLC PDU includes a first user identification ID field and an AM enable field, the first user ID field is used to indicate the device identification of the terminal, and the AM enable field is used to indicate the confirmation mode supported by the terminal at the SLC layer; when the value of the AMenable field is used to indicate that the terminal supports the Cpack confirmation mode, the Beidou network device sends a first Cpack feedback frame to the terminal, and the first Cpack feedback frame is used to indicate the reception status of the Beidou network device for the M SLC PDUs; wherein the first Cpack feedback frame includes a first user CID field, the first user CID field is used to indicate the compact device identification of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

[0018] In one possible implementation, the method also includes: when the value of the AM enable field is used to indicate that the terminal supports the complete Apack confirmation mode, the Beidou network device sends a first complete Apack feedback frame to the terminal, and the first Apack feedback frame is used to indicate the reception status of the Beidou network device for the N SLC PDUs; wherein, the frame header of the first Apack feedback frame includes a second user ID field, and the second user ID field is used to indicate the device identification of the terminal, and the value of the second user ID field is the same as the value of the first user ID field.

[0019] In a possible implementation, the frame header of the first Apack feedback frame further includes a first frame type field, where the first frame type field is used to indicate that the frame type of the first Apack feedback frame is an integrity confirmation identifier Apack ACK frame or an Apack receipt frame.

[0020] In a possible implementation, the frame header of the first Apack feedback frame further includes a start identification field, wherein the start identification field is located at the starting position in the frame header of the first Apack feedback frame, and the start identification field is used to identify the starting position of the first Apack feedback frame.

[0021] In one possible implementation, the frame header of the first Cpack feedback frame includes a second frame type field and a first frame length field, the value of the second frame type field is used to indicate that the frame type of the first Cpack feedback frame is a flexible feedback frame, and the first frame length field is used to indicate the total data length of the first user CID field and feedback information in the first Cpack feedback frame.

[0022] In one possible implementation, the frame header of the first Cpack feedback frame includes a third frame type field and a first frame subtype field, the value of the third frame type field is used to indicate that the frame type of the first Cpack feedback frame is a compact frame, and the value of the first frame subtype field is used to indicate that the frame subtype of the first Cpack feedback frame is a compact confirmation identifier Cpack ACK frame or a Cpack receipt frame.

[0023] In a possible implementation, the frame header of the first Cpack feedback frame includes a fourth frame type field, and a value of the fourth frame type field is used to indicate that the frame type of the first Cpack feedback frame is a Cpack ACK frame or a Cpack receipt frame.

[0024] In a possible implementation, the data length of the start identifier field is the same as the data length of the first user CID field.

[0025] In one possible implementation, the data length of the start identification field is a first length; wherein, when the data length of the specified portion of data in the first user ID field is the first length and is different from the value of the start identification field, the value of the first user CID field is the specified portion of data in the first user ID field; when the data length of the specified portion of data in the first user ID field is the same as the value of the start identification field, the value of the first user CID field is the sum of the specified portion of data in the first user ID field and a preset value.

[0026] In a possible implementation, the Beidou network device sends the first Cpack feedback frame to the terminal, specifically including: the Beidou network device puts the first Cpack general data frame into a first physical frame; and the Beidou network device sends the first physical frame to the terminal.

[0027] In a third aspect, the present application provides a Beidou communication system, comprising: a terminal and a Beidou network device; wherein the terminal can execute the method in any possible implementation of the first aspect. The Beidou network device can execute the method in any possible implementation of the first aspect.

[0028] In a fourth aspect, the present application provides a communication device comprising one or more processors, one or more memories, and a transceiver. The transceiver and the one or more memories are coupled to the one or more processors, the one or more memories being configured to store computer program code, the computer program code comprising computer instructions. When the one or more processors execute the computer instructions, the communication device performs the method of any possible implementation of the first aspect described above.

[0029] The communication device may be a terminal or other product-type equipment.

[0030] In a fifth aspect, the present application provides a communication device comprising one or more processors, one or more memories, and a transceiver. The transceiver and the one or more memories are coupled to the one or more processors, the one or more memories being configured to store computer program code, the computer program code comprising computer instructions. When the one or more processors execute the computer instructions, the communication device performs the method of any possible implementation of the second aspect described above.

[0031] The communication device may be a Beidou network device, or any network element or a combination of multiple network elements in the Beidou network device.

[0032] In a sixth aspect, the present application provides a computer storage medium comprising computer instructions, which, when executed on a computer, enable the computer to execute the method in any possible implementation of the first aspect.

[0033] In a seventh aspect, the present application provides a computer storage medium comprising computer instructions, which, when executed on a computer, enable the computer to execute the method in any possible implementation of the second aspect.

[0034] In an eighth aspect, the present application provides a computer program product, which, when executed on a computer, enables the computer to execute the method in any possible implementation of the first aspect.

[0035] In a ninth aspect, the present application provides a computer program product, which, when executed on a computer, enables the computer to execute the method in any possible implementation of the second aspect.

[0036] In the tenth aspect, the present application provides a chip or chip system, which is applied to a terminal, including a processing circuit and an interface circuit, the interface circuit is used to receive code instructions and transmit them to the processing circuit, and the processing circuit is used to run the code instructions to execute the method in any possible implementation of the first aspect above.

[0037] Among them, for the beneficial effects of the second to sixth aspects, please refer to the beneficial effects of the first aspect and will not be repeated. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of the architecture of a Beidou communication system provided in an embodiment of the present application;

[0039] Figure 2A A schematic diagram of the data inbound transmission process in a Beidou communication system provided in an embodiment of the present application;

[0040] Figure 2BA schematic diagram of the data outbound transmission process in a Beidou communication system provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the hardware structure of a terminal provided in an embodiment of the present application;

[0042] Figure 4A A schematic diagram of a protocol encapsulation architecture for inbound data of a Beidou communication system provided in an embodiment of the present application;

[0043] Figure 4B A schematic diagram of a protocol parsing architecture for inbound data of a Beidou communication system provided in an embodiment of the present application;

[0044] Figure 5A A schematic diagram of a protocol encapsulation architecture for outbound data of a Beidou communication system provided in an embodiment of the present application;

[0045] Figure 5B A schematic diagram of a protocol parsing architecture for outbound data of a Beidou communication system provided in an embodiment of the present application;

[0046] Figure 6A A schematic diagram of the frame format of an outbound universal data frame provided in an embodiment of the present application;

[0047] Figure 6B This is a schematic diagram of the frame format of an outbound Apack ACK frame provided in an embodiment of the present application;

[0048] Figure 6C This is a schematic diagram of the frame format of an outbound receipt frame provided in an embodiment of the present application;

[0049] Figure 6D A schematic diagram of the frame format of an outbound Cpack ACK frame provided in an embodiment of the present application;

[0050] Figure 7 A schematic diagram of a scheduling process for outbound user frames provided in an embodiment of the present application;

[0051] Figure 8A This is a schematic diagram of the frame format of another outbound universal data frame provided in an embodiment of the present application;

[0052] Figure 8B This is a schematic diagram of the frame format of another outbound ACK frame provided in an embodiment of the present application;

[0053] Figure 8C This is a schematic diagram of the frame format of another outbound receipt frame provided in an embodiment of the present application;

[0054] Figure 8D-Figure 8IA schematic diagram of the frame format of a set of outbound flexible feedback frames provided in an embodiment of the present application;

[0055] Figure 9 A schematic diagram of another outbound user frame scheduling process provided in an embodiment of the present application;

[0056] Figure 10A A schematic diagram of the frame format of an outbound Apack universal data frame provided in an embodiment of the present application;

[0057] Figure 10B This is a schematic diagram of the frame format of an outbound Apack ACK frame provided in an embodiment of the present application;

[0058] Figure 10C This is a schematic diagram of the frame format of an outbound Apack receipt frame provided in an embodiment of the present application;

[0059] Figure 10D-10F A schematic diagram of the frame format of a group of outbound compact frames provided in an embodiment of the present application;

[0060] Figure 11 A schematic diagram of another outbound user frame scheduling process provided in an embodiment of the present application;

[0061] Figure 12A This is a schematic diagram of the frame format of an outbound Apack universal data frame provided in another embodiment of the present application;

[0062] Figure 12B This is a schematic diagram of the frame format of an outbound Apack ACK frame provided in another embodiment of the present application;

[0063] Figure 12C This is a schematic diagram of the frame format of an outbound Apack receipt frame provided in another embodiment of the present application;

[0064] Figure 12D This is a schematic diagram of the frame format of an outbound Cpack universal data frame provided in another embodiment of the present application;

[0065] Figure 12E This is a schematic diagram of the frame format of an outbound CpackACK frame provided in another embodiment of the present application;

[0066] Figure 12F This is a schematic diagram of the frame format of an outbound Cpack receipt frame provided in another embodiment of the present application;

[0067] Figure 13 A schematic diagram of another outbound user frame scheduling process provided in an embodiment of the present application;

[0068] Figure 14A flowchart of a compact feedback method in a Beidou communication system provided in an embodiment of the present application;

[0069] Figure 15 A schematic diagram of the frame format of an SLC PDU provided in an embodiment of the present application;

[0070] Figure 16 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0071] Figure 17 A schematic structural diagram of another communication device provided in an embodiment of the present application;

[0072] Figure 18 A schematic structural diagram of another communication device provided in an embodiment of the present application;

[0073] Figure 19 A schematic diagram of the structure of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0074] The following is a clear and detailed description of the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in the text is only a description of the association relationship between related objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0075] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of the technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this application, unless otherwise specified, "plurality" means two or more.

[0076] The following introduces a Beidou communication system 10 provided in an embodiment of the present application.

[0077] Figure 1 A schematic diagram of the architecture of a Beidou communication system 10 provided in an embodiment of the present application is shown.

[0078] As above Figure 1 As shown, the Beidou communication system 10 may include a terminal 100, a Beidou short message satellite 21, a Beidou network device 200, a short message center 25, and a terminal 300. Optionally, the Beidou communication system 10 may further include a national emergency rescue platform 26 and a national emergency rescue center 27.

[0079] Terminal 100 can send short messages to BeiDou short message satellites 21. BeiDou short message satellites 21 only relay the short messages sent by terminal 100 and directly forward them to BeiDou network devices 200 on the ground. BeiDou network devices 200 can parse the short messages forwarded by the satellites according to the BeiDou communication protocol and forward the general message content parsed from the short messages to a short message service center (SMSC) 25. The SMSC 25 can forward the message content to terminal 300 via a traditional cellular communication network. BeiDou network devices 200 can also transmit emergency messages sent by terminal 100 to the National Emergency Rescue Center 27 via the National Emergency Rescue Platform 26.

[0080] The terminal 300 can also send a short message to the short message center 25 through a traditional cellular communication network. The short message center 25 can forward the short message of the terminal 300 to the Beidou network device 200. The Beidou network device 200 can relay the short message of the terminal 300 to the terminal 100 via the Beidou short message satellite 21.

[0081] Among them, the above-mentioned Beidou network equipment 200 may include a Beidou ground transceiver station 22, a Beidou central station 23 and a Beidou short message fusion communication platform 24. Among them, the Beidou ground transceiver station 22 may include one or more devices with a sending function and one or more devices with a receiving function, or may include one or more devices with a sending function and a receiving function, which is not limited here. The Beidou ground transceiver station 22 can be used for the Beidou network equipment 200 to process data at the physical layer (physical layer protocol, PHY). The Beidou central station 23 can be used for the Beidou network equipment 200 to process data at the satellite link layer (satellite link control protocol, SLC) layer and the message data convergence protocol (message data convergence protocol, MDCP). The Beidou short message fusion communication platform 24 can be used for the data processing function at the application layer (application layer protocol, APP).

[0082] Because the BeiDou communication system 10 communicates via satellite links, its main characteristics are long latency (approximately 270ms one-way) and high link loss. Currently, the BeiDou communication system 10 primarily supports short message bursts, and does not support connection status management, mobility management, or broadcast control information.

[0083] The terminal 100 can actively send data to the Beidou network device 200 via the Beidou short message satellite 21. However, due to the lack of air interface signaling, the ground central station cannot actively page the user. Due to the long transmission distance of satellite communication, the Beidou communication system 10 requires high transmission power for the terminal 100. Due to the limitations of the radio frequency components on the current terminal 100, the terminal 100 cannot continuously send signals to the Beidou short message satellite 21 for a long time. In order to minimize damage to the radio frequency components on the terminal 100, the radio frequency components of the terminal 100 must stop working for a period of time after being in the sending state for a period of time before switching to the sending state to continue working. The duration of the sending state on the terminal 100 is determined by the underlying hardware capabilities of the terminal 100. In the above-mentioned Beidou communication system 10, in order to ensure that the data received and sent by the terminal 100 do not interfere with each other, the terminal 100 does not support sending and receiving data at the same time. The terminal 100 needs to wait for receiving data sent by the Beidou network device 200 after sending data.

[0084] The working mode of the Beidou network device 200 may be a duplex mode, in which data can be sent and received simultaneously, and the Beidou network device 200 may send and receive data for a long time.

[0085] Figure 2A The present invention shows an inbound data transmission process in a Beidou communication system provided by an embodiment of the present application.

[0086] like Figure 2A As shown, data inbound may refer to the terminal 100 sending data to the Beidou network device 200. For example, the terminal 100 may send a data frame to the Beidou ground transceiver station 22. The Beidou ground transceiver station 22 may send the data frame to the Beidou central station 23. The Beidou central station 23 may aggregate the data frames into an application layer message and report it to the Beidou short message fusion communication platform 24. After receiving the data frame sent by the terminal 100, the Beidou central station 23 may return an SLC layer acknowledgment character (ACK) to the terminal 100. The ACK may be used to indicate whether the Beidou network device 200 has successfully received the data frame sent by the terminal 100.

[0087] Figure 2B The embodiment of the present application provides a data outbound transmission process in a Beidou communication system.

[0088] like Figure 2BAs shown, data outbound can refer to the Beidou network device 200 sending data to the terminal 100. For example, the Beidou short message fusion communication platform 24 in the Beidou network device 200 can send an application layer message to the Beidou central station 23; the Beidou central station 23 can then split the application layer message into one or more data frames and send them to the Beidou ground transceiver station 22, which is then relayed by the Beidou short message satellite 21 and sent to the terminal 100. Optionally, after receiving the data frame, the terminal 100 can return an SLC layer ACK to the Beidou central station 23. This ACK can be used to confirm whether the terminal 100 has successfully received the data frame sent by the Beidou network device 200.

[0089] Figure 3 A schematic structural diagram of the terminal 100 is shown.

[0090] The embodiment will be described in detail below using terminal 100 as an example. It should be understood that Figure 3 The terminal 100 shown is only an example, and the terminal 100 may have more Figure 3 More or fewer components may be shown, two or more components may be combined, or the components may be arranged differently. Figure 3 The various components shown in the drawings may be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and / or application specific integrated circuits.

[0091] The terminal 100 may include: a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, a sensor module 180, a button 190, a motor 191, an indicator 192, a camera 193, a display 194, and a subscriber identification module (SIM) card interface 195, etc. The sensor module 180 may include a pressure sensor 180A, a gyroscope sensor 180B, an air pressure sensor 180C, a magnetic sensor 180D, an acceleration sensor 180E, a distance sensor 180F, a proximity light sensor 180G, a fingerprint sensor 180H, a temperature sensor 180J, a touch sensor 180K, an ambient light sensor 180L, a bone conduction sensor 180M, etc.

[0092] It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on terminal 100. In other embodiments of the present application, terminal 100 may include more or fewer components than shown, or may combine or separate certain components, or arrange the components differently. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0093] The processor 110 may include one or more processing units. For example, the processor 110 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The different processing units may be independent devices or integrated into one or more processors.

[0094] The controller may be the nerve center and command center of the terminal 100. The controller may generate an operation control signal according to the instruction operation code and the timing signal to complete the control of fetching and executing instructions.

[0095] Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the same instruction or data again, it can directly access the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency.

[0096] In some embodiments, the processor 110 may include one or more interfaces. The interfaces may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a universal serial bus (USB) interface.

[0097] The I2C interface is a bidirectional synchronous serial bus that includes a serial data line (SDA) and a serial clock line (SCL). In some embodiments, the processor 110 may include multiple I2C busses. The processor 110 may be coupled to the touch sensor 180K, the charger, the flash, the camera 193, and the like via different I2C bus interfaces. For example, the processor 110 may be coupled to the touch sensor 180K via the I2C interface, enabling communication between the processor 110 and the touch sensor 180K via the I2C bus interface, thereby implementing the touch function of the terminal 100.

[0098] The I2S interface can be used for audio communication. In some embodiments, the processor 110 can include multiple I2S buses. The processor 110 can be coupled to the audio module 170 via the I2S bus to enable communication between the processor 110 and the audio module 170. In some embodiments, the audio module 170 can transmit audio signals to the wireless communication module 160 via the I2S interface, enabling the function of answering calls through a Bluetooth headset.

[0099] The PCM interface can also be used for audio communication, sampling, quantizing, and encoding analog signals. In some embodiments, the audio module 170 and the wireless communication module 160 can be coupled via a PCM bus interface. In some embodiments, the audio module 170 can also transmit audio signals to the wireless communication module 160 via the PCM interface, enabling the function of answering calls via a Bluetooth headset. Both the I2S interface and the PCM interface can be used for audio communication.

[0100] The UART interface is a universal serial data bus used for asynchronous communication. This bus can be a bidirectional communication bus. It converts the data to be transmitted between serial communication and parallel communication. In some embodiments, the UART interface is typically used to connect the processor 110 and the wireless communication module 160. For example, the processor 110 communicates with the Bluetooth module in the wireless communication module 160 via the UART interface to implement Bluetooth functionality. In some embodiments, the audio module 170 can transmit audio signals to the wireless communication module 160 via the UART interface, enabling the function of playing music through Bluetooth headphones.

[0101] The MIPI interface can be used to connect the processor 110 to peripheral devices such as the display 194 and the camera 193. MIPI interfaces include the camera serial interface (CSI) and the display serial interface (DSI). In some embodiments, the processor 110 and the camera 193 communicate via the CSI interface to implement the camera function of the terminal 100. The processor 110 and the display 194 communicate via the DSI interface to implement the display function of the terminal 100.

[0102] The GPIO interface can be configured via software. The GPIO interface can be configured as either a control signal or a data signal. In some embodiments, the GPIO interface can be used to connect the processor 110 to the camera 193, display 194, wireless communication module 160, audio module 170, sensor module 180, etc. The GPIO interface can also be configured as an I2C interface, an I2S interface, a UART interface, a MIPI interface, etc.

[0103] The USB interface 130 is an interface that complies with USB standards and may be a Mini USB interface, a Micro USB interface, a USB Type-C interface, or the like. The USB interface 130 can be used to connect a charger to charge the terminal 100 and to transfer data between the terminal 100 and peripheral devices. It can also be used to connect headphones to play audio. This interface can also be used to connect other electronic devices, such as augmented reality devices.

[0104] It is understood that the interface connection relationship between the modules illustrated in the embodiment of the present invention is merely an illustrative description and does not constitute a structural limitation on the terminal 100. In other embodiments of the present application, the terminal 100 may also adopt a different interface connection method from the above embodiment, or a combination of multiple interface connection methods.

[0105] The charging management module 140 is configured to receive charging input from a charger. The charger can be either a wireless charger or a wired charger. In some wired charging embodiments, the charging management module 140 can receive charging input from the wired charger via the USB interface 130. In some wireless charging embodiments, the charging management module 140 can receive wireless charging input via the wireless charging coil of the terminal 100. While charging the battery 142, the charging management module 140 can also power the electronic device through the power management module 141.

[0106] The power management module 141 is used to connect the battery 142, the charging management module 140 and the processor 110. The power management module 141 receives input from the battery 142 and / or the charging management module 140, and provides power to the processor 110, the internal memory 121, the external memory, the display 194, the camera 193, and the wireless communication module 160. The power management module 141 can also be used to monitor parameters such as battery capacity, battery cycle count, and battery health status (leakage, impedance). In some other embodiments, the power management module 141 can also be set in the processor 110. In other embodiments, the power management module 141 and the charging management module 140 can also be set in the same device.

[0107] The wireless communication function of the terminal 100 can be implemented through the antenna 1, the antenna 2, the mobile communication module 150, the wireless communication module 160, the modem processor and the baseband processor.

[0108] Antenna 1 and Antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in terminal 100 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, antenna 1 can be reused as a diversity antenna for a wireless local area network. In other embodiments, the antennas can be used in conjunction with a tuning switch.

[0109] The mobile communication module 150 can provide solutions for wireless communications including 2G / 3G / 4G / 5G applied on the terminal 100. The mobile communication module 150 may include at least one filter, a switch, a power amplifier, a low noise amplifier (LNA), etc. The mobile communication module 150 can receive electromagnetic waves from the antenna 1, and filter, amplify, and process the received electromagnetic waves, and transmit them to the modulation and demodulation processor for demodulation. The mobile communication module 150 can also amplify the signal modulated by the modulation and demodulation processor, and convert it into electromagnetic waves for radiation through the antenna 1. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the processor 110. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the same device as at least some of the modules of the processor 110.

[0110] The modem processor may include a modulator and a demodulator. The modulator is used to modulate the low-frequency baseband signal to be transmitted into a medium-high frequency signal. The demodulator is used to demodulate the received electromagnetic wave signal into a low-frequency baseband signal. The demodulator then transmits the demodulated low-frequency baseband signal to the baseband processor for processing. After being processed by the baseband processor, the low-frequency baseband signal is passed to the application processor. The application processor outputs a sound signal through an audio device (not limited to the speaker 170A, the receiver 170B, etc.) or displays an image or video through the display screen 194. In some embodiments, the modem processor may be an independent device. In other embodiments, the modem processor may be independent of the processor 110 and be set in the same device as the mobile communication module 150 or other functional modules.

[0111] The wireless communication module 160 can provide wireless communication solutions applied on the terminal 100, including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), satellite communication module, frequency modulation (FM), near field communication (NFC), infrared technology (IR), etc. The wireless communication module 160 can be one or more devices integrating at least one communication processing module. The wireless communication module 160 receives electromagnetic waves via the antenna 2, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 110. The wireless communication module 160 can also receive the signal to be sent from the processor 110, frequency modulate it, amplify it, and convert it into electromagnetic waves for radiation through the antenna 2.

[0112] Among them, the satellite communication module can be used to communicate with satellite network equipment. For example, in the Beidou communication system, the satellite communication module can communicate with the Beidou network equipment 200, and the satellite communication module can support short message transmission between the Beidou network equipment 200.

[0113] In some embodiments, the antenna 1 of the terminal 100 is coupled to the mobile communication module 150, and the antenna 2 is coupled to the wireless communication module 160, so that the terminal 100 can communicate with the network and other devices through wireless communication technologies. The wireless communication technologies may include global system for mobile communications (GSM), general packet radio service (GPRS), code division multiple access (CDMA), wideband code division multiple access (WCDMA), time-division code division multiple access (TD-SCDMA), long term evolution (LTE), BT, GNSS, WLAN, NFC, FM, and / or IR technology. The GNSS may include a global positioning system (GPS), a global navigation satellite system (GLONASS), a Beidou navigation satellite system (BDS), a quasi-zenith satellite system (QZSS) and / or a satellite based augmentation system (SBAS).

[0114] Terminal 100 implements display functions through a GPU, display screen 194, and an application processor. The GPU is a microprocessor for image processing that connects display screen 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or modify display information.

[0115] Display screen 194 is used to display images, videos, and the like. Display screen 194 includes a display panel. The display panel can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), a MiniLED, a MicroLED, a Micro-oLed, or a quantum dot light-emitting diode (QLED). In some embodiments, terminal 100 may include one or N display screens 194, where N is a positive integer greater than one.

[0116] The terminal 100 can realize the shooting function through the ISP, camera 193, video codec, GPU, display screen 194 and application processor.

[0117] The ISP processes data fed back by camera 193. For example, when taking a photo, the shutter is opened, and light is transmitted through the lens to the camera's photosensitive element. The light signal is converted into an electrical signal, which is then passed to the ISP for processing and converted into a visible image. The ISP can also perform algorithmic optimization on image noise, brightness, and skin tone. It can also optimize parameters such as exposure and color temperature of the captured scene. In some embodiments, the ISP can be located within camera 193.

[0118] The camera 193 is used to capture still images or videos. The object generates an optical image through the lens and projects it onto the photosensitive element. The photosensitive element can be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the light signal into an electrical signal, and then passes the electrical signal to the ISP for conversion into a digital image signal. The ISP outputs the digital image signal to the DSP for processing. The DSP converts the digital image signal into an image signal in a standard RGB, YUV or other format. In some embodiments, the terminal 100 may include 1 or N cameras 193, where N is a positive integer greater than 1.

[0119] The digital signal processor is used to process digital signals. In addition to processing digital image signals, it can also process other digital signals. For example, when the terminal 100 selects a frequency point, the digital signal processor is used to perform Fourier transform on the frequency point energy.

[0120] Video codecs are used to compress or decompress digital video. Terminal 100 may support one or more video codecs. This allows terminal 100 to play or record videos in various encoding formats, such as Moving Picture Experts Group (MPEG) 1, MPEG2, MPEG3, and MPEG4.

[0121] The NPU is a neural network (NN) computing processor. Drawing on the structure of biological neural networks, such as the transmission patterns between neurons in the human brain, it rapidly processes input information and can continuously self-learn. The NPU enables intelligent cognitive applications in the terminal 100, such as image recognition, face recognition, speech recognition, and text comprehension.

[0122] The external memory interface 120 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the terminal 100. The external memory card communicates with the processor 110 via the external memory interface 120 to implement data storage functions. For example, files such as music and videos can be stored on the external memory card.

[0123] The internal memory 121 can be used to store computer executable program codes, which include instructions. The processor 110 executes various functional applications and data processing of the terminal 100 by running the instructions stored in the internal memory 121. The internal memory 121 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc. The data storage area can store data created during the use of the terminal 100 (such as audio data, a phone book, etc.), etc. In addition, the internal memory 121 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc.

[0124] The terminal 100 can implement audio functions such as music playback and recording through the audio module 170, the speaker 170A, the receiver 170B, the microphone 170C, the headphone jack 170D, and the application processor.

[0125] The audio module 170 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. The audio module 170 can also be used to encode and decode audio signals. In some embodiments, the audio module 170 can be provided in the processor 110, or some functional modules of the audio module 170 can be provided in the processor 110.

[0126] The speaker 170A, also called a "horn", is used to convert an audio electrical signal into a sound signal. The terminal 100 can listen to music or listen to a hands-free call through the speaker 170A.

[0127] The receiver 170B, also called a "handset", is used to convert audio electrical signals into sound signals. When the terminal 100 receives a call or a voice message, the user can place the receiver 170B close to the ear to hear the voice.

[0128] Microphone 170C, also known as "microphone" or "microphone", is used to convert sound signals into electrical signals. When making a call or sending a voice message, the user can speak by putting their mouth close to the microphone 170C to input the sound signal into the microphone 170C. The terminal 100 can be provided with at least one microphone 170C. In other embodiments, the terminal 100 can be provided with two microphones 170C, which can not only collect sound signals but also realize noise reduction function. In other embodiments, the terminal 100 can also be provided with three, four or more microphones 170C to realize sound signal collection, noise reduction, and identification of sound sources, and realize directional recording function, etc.

[0129] The headphone jack 170D is used to connect a wired headphone and can be the USB interface 130 or a 3.5mm open mobile terminal platform (OMTP) standard interface or a cellular telecommunications industry association of the USA (CTIA) standard interface.

[0130] Pressure sensor 180A is used to sense pressure signals and convert them into electrical signals. In some embodiments, pressure sensor 180A can be located on display screen 194. There are many types of pressure sensors 180A, such as resistive, inductive, and capacitive. A capacitive pressure sensor can include at least two parallel plates made of conductive material. When force is applied to pressure sensor 180A, the capacitance between the electrodes changes. Terminal 100 determines the intensity of the pressure based on this change in capacitance. When a touch operation is applied to display screen 194, terminal 100 detects the touch intensity based on pressure sensor 180A. Terminal 100 can also calculate the touch location based on the detection signal from pressure sensor 180A. In some embodiments, touch operations applied to the same touch location but with different touch intensities can correspond to different operation instructions. For example, when a touch operation with an intensity less than a first pressure threshold is applied to a short message application icon, a command to view short messages is executed. When a touch operation with an intensity greater than or equal to the first pressure threshold is applied to a short message application icon, a command to create a new short message is executed.

[0131] The gyroscope sensor 180B can be used to determine the motion posture of the terminal 100. In some embodiments, the angular velocity of the terminal 100 around three axes (i.e., x, y, and z axes) can be determined by the gyroscope sensor 180B. The gyroscope sensor 180B can be used for anti-shake shooting. For example, when the shutter is pressed, the gyroscope sensor 180B detects the angle of the terminal 100 shaking, calculates the distance that the lens module needs to compensate based on the angle, and allows the lens to offset the shaking of the terminal 100 through reverse movement to achieve anti-shake. The gyroscope sensor 180B can also be used for navigation and somatosensory game scenes.

[0132] The air pressure sensor 180C is used to measure air pressure. In some embodiments, the terminal 100 calculates the altitude using the air pressure value measured by the air pressure sensor 180C to assist in positioning and navigation.

[0133] The magnetic sensor 180D includes a Hall sensor. The terminal 100 can use the magnetic sensor 180D to detect the opening and closing of the flip case. In some embodiments, when the terminal 100 is a flip phone, the terminal 100 can detect the opening and closing of the flip cover based on the magnetic sensor 180D. Furthermore, based on the detected opening and closing status of the case or flip cover, features such as automatic unlocking of the flip cover can be configured.

[0134] Accelerometer 180E can detect the magnitude of acceleration of terminal 100 in all directions (generally three axes). When terminal 100 is stationary, it can detect the magnitude and direction of gravity. It can also be used to identify the electronic device's posture, enabling applications such as switching between landscape and portrait modes and pedometers.

[0135] The distance sensor 180F is used to measure distance. The terminal 100 can measure distance using infrared or laser. In some embodiments, when shooting a scene, the terminal 100 can use the distance sensor 180F to measure distance to achieve fast focusing.

[0136] The proximity light sensor 180G may include, for example, a light emitting diode (LED) and a light detector, such as a photodiode. The light emitting diode may be an infrared light emitting diode. The terminal 100 emits infrared light outward through the light emitting diode. The terminal 100 uses the photodiode to detect infrared reflected light from nearby objects. When sufficient reflected light is detected, it can be determined that there is an object near the terminal 100. When insufficient reflected light is detected, the terminal 100 can determine that there is no object near the terminal 100. The terminal 100 can use the proximity light sensor 180G to detect when the user holds the terminal 100 close to the ear to talk, so as to automatically turn off the screen to save power. The proximity light sensor 180G can also be used in leather case mode and pocket mode to automatically unlock and lock the screen.

[0137] Ambient light sensor 180L is used to sense ambient light brightness. Terminal 100 can adaptively adjust the brightness of display screen 194 based on the perceived ambient light brightness. Ambient light sensor 180L can also be used to automatically adjust white balance when taking photos. Ambient light sensor 180L can also work with proximity light sensor 180G to detect whether terminal 100 is in a pocket to prevent accidental touches.

[0138] The fingerprint sensor 180H is used to collect fingerprints. The terminal 100 can use the collected fingerprint characteristics to implement fingerprint unlocking, access application locks, fingerprint photography, fingerprint call answering, etc.

[0139] Temperature sensor 180J is used to detect temperature. In some embodiments, terminal 100 uses the temperature detected by temperature sensor 180J to implement a temperature handling strategy. For example, when the temperature reported by temperature sensor 180J exceeds a threshold, terminal 100 reduces the performance of a processor located near temperature sensor 180J to reduce power consumption and implement thermal protection. In other embodiments, when the temperature falls below another threshold, terminal 100 heats battery 142 to prevent abnormal shutdown of terminal 100 due to low temperature. In other embodiments, when the temperature falls below yet another threshold, terminal 100 boosts the output voltage of battery 142 to prevent abnormal shutdown due to low temperature.

[0140] The touch sensor 180K is also called a "touch panel." The touch sensor 180K can be disposed on the display screen 194. The touch sensor 180K and the display screen 194 form a touch screen, also called a "touch screen." The touch sensor 180K is used to detect touch operations applied thereto or in the vicinity thereof. The touch sensor can transmit the detected touch operations to the application processor to determine the type of touch event. Visual output related to the touch operations can be provided via the display screen 194. In other embodiments, the touch sensor 180K can also be disposed on the surface of the terminal 100, in a location different from that of the display screen 194.

[0141] The bone conduction sensor 180M can obtain vibration signals. In some embodiments, the bone conduction sensor 180M can obtain vibration signals from the vibrating bones of the human body. The bone conduction sensor 180M can also contact the human pulse to receive blood pressure pulse signals. In some embodiments, the bone conduction sensor 180M can also be set in headphones to form bone conduction headphones. The audio module 170 can parse out voice signals based on the vibration signals of the vibrating bones of the human body obtained by the bone conduction sensor 180M to implement voice functions. The application processor can parse heart rate information based on the blood pressure pulse signals obtained by the bone conduction sensor 180M to implement heart rate detection functions.

[0142] Keys 190 include a power button, a volume button, etc. Keys 190 may be mechanical keys or touch keys. Terminal 100 may receive key inputs and generate key signal inputs related to user settings and function control of terminal 100.

[0143] Motor 191 can generate vibration prompts. Motor 191 can be used for incoming call vibration prompts, and can also be used for touch vibration feedback. For example, touch operations acting on different applications (such as taking pictures, audio playback, etc.) can correspond to different vibration feedback effects. For touch operations acting on different areas of the display screen 194, motor 191 can also correspond to different vibration feedback effects. Different application scenarios (for example: time reminders, receiving messages, alarm clocks, games, etc.) can also correspond to different vibration feedback effects. The touch vibration feedback effect can also support customization.

[0144] The indicator 192 may be an indicator light, which may be used to indicate the charging status, power level changes, messages, missed calls, notifications, etc.

[0145] The SIM card interface 195 is used to connect a SIM card. The SIM card can be connected to or disconnected from the terminal 100 by inserting it into or removing it from the SIM card interface 195. The terminal 100 can support 1 or N SIM card interfaces, where N is a positive integer greater than 1. The SIM card interface 195 can support Nano SIM cards, Micro SIM cards, SIM cards, and the like. Multiple cards can be inserted into the same SIM card interface 195 at the same time. The types of the multiple cards can be the same or different. The SIM card interface 195 can also be compatible with different types of SIM cards. The SIM card interface 195 can also be compatible with external memory cards. The terminal 100 interacts with the network through the SIM card to implement functions such as calls and data communications. In some embodiments, the terminal 100 uses an eSIM, i.e., an embedded SIM card. The eSIM card can be embedded in the terminal 100 and cannot be separated from the terminal 100.

[0146] The following describes a protocol encapsulation architecture for inbound data of a Beidou communication system 10 provided in an embodiment of the present application.

[0147] Figure 4A A schematic diagram of a protocol encapsulation architecture for inbound data of a Beidou communication system 10 provided in an embodiment of the present application is shown.

[0148] like Figure 4A As shown, the Beidou message transmission protocol layer on the terminal 100 can be divided into an application layer (application layer protocol), a message data convergence protocol (MDCP), a satellite link control protocol (SLC) and a physical layer (PHY).

[0149] When the terminal 100 sends data to the BeiDou network device 200, the workflow of the BeiDou message transmission protocol on the terminal 100 may be as follows:

[0150] At the APP layer, terminal 100 can compress the original data into compressed data using a compression algorithm and add a compression indication field to the front of the compressed data. The compression indication field can be used to indicate the compression algorithm type used for the compressed data. Terminal 100 can then encrypt the compressed data to obtain encrypted data and add an encryption indication field to the header of the encrypted data. The encryption indication field is used to indicate the encryption algorithm type used for the encrypted data. Terminal 100 can encapsulate the encrypted data, the compression indication field, and the encryption indication field into an application layer message and send it to the MDCP layer. The application layer message includes a message header and message data. The message header includes a compression indication field, an encryption indication field, etc. The message data includes the encrypted data.

[0151] Optionally, the terminal 100 may also encrypt the compression indication field and the compressed data together to obtain encrypted data.

[0152] At the MDCP layer, terminal 100 can obtain the application layer message sent by the APP layer through the inter-layer interface and treat the application layer message as an MDCP SDU. Due to air interface limitations, terminal 100 can only send physical frames of a specified length at the physical layer at a time. This constrains the length of the MDCP layer data to the specified length. Therefore, at the MDCP layer, terminal 100 can add padding data (padding) to the end of the MDCP SDU to a specified length and add a redundant length indication field to the header of the MDCP SDU. The redundant length indication field can be used to indicate the length of the padding data. Terminal 100 can split the padding data and the MDCP SDU after adding the redundant length indication field into one or more fixed-length MDCP segments (M_segments) and add a subsequent indication field to the header of each MDCP segment to obtain an MDCP PDU. That is, the MDCP PDU includes the M_segment and subsequent indication fields. The subsequent indication field may be used to indicate whether the current MDCP PDU is the starting MDCP PDU, the middle MDCP PDU or the last MDCP PDU among a plurality of MDCP PDUs sent continuously; or, it is a separately sent MDCP PDU.

[0153] At the SLC layer, the terminal 100 can obtain the MDCP PDU sent by the MDCP layer through the inter-layer interface as an SLC SDU. At the SLC layer, the terminal 100 can segment the SLC SDU into one or more (up to 4) fixed-length SLC segments (S_segments) and add frame header information to the header of each S_segment to obtain an SLC PDU.

[0154] At the PHY layer, the terminal 100 can obtain the SLC PDU sent by the SLC layer through the inter-layer interface as the code block of the PHY layer, and add a synchronization header to the head of the code block and a check bit field to the tail of the code block. In the above-mentioned Beidou communication system 10, a cyclic redundancy check (CRC) can be used to check the code block, so the check bit field can include a CRC code. The terminal 100 can encode the code block and the check bit field (for example, polar coding) to obtain coded data, and then insert a pilot into the coded data to obtain pilot coded data (pilot+data). Then, the terminal 100 modulates the synchronization header and pilot coded data in sequence through the underlying hardware to obtain modulated data (modulateddata). The terminal 100 can spread the modulated data to obtain spread spectrum modulated data (spread+modulateddata). The terminal 100 can send the spread spectrum modulated data to the Beidou short message satellite 21, which is relayed to the Beidou network device 200 via the Beidou short message satellite 21.

[0155] The following describes a protocol parsing architecture for inbound data of a Beidou communication system 10 provided in an embodiment of the present application.

[0156] Figure 4B A schematic diagram of a protocol parsing architecture for inbound data of a Beidou communication system 10 provided in an embodiment of the present application is shown.

[0157] like Figure 4B As shown, the BeiDou short message transmission protocol layer of the BeiDou network device 200 can be divided into an application layer protocol, a message data convergence protocol (MDCP), a satellite link control protocol (SLC), and a physical layer protocol (PHY). Among them, the BeiDou network device 200 can include a BeiDou ground transceiver station 22, a BeiDou central station 23, and a BeiDou short message fusion communication platform 24. The BeiDou ground transceiver station 22 can be used to be responsible for the protocol processing of the PHY layer. The BeiDou central station 23 can be used to be responsible for the protocol processing of the SLC layer and the MDCP layer. The BeiDou short message fusion communication platform 24 can be used to be responsible for the protocol processing of the APP layer.

[0158] When the BeiDou network device 200 receives data sent by the terminal 100, the workflow of the BeiDou short message transmission protocol layer of the BeiDou network device 200 may be as follows:

[0159] At the PHY layer, the Beidou network device 200 can obtain the pilot coded data after modulation and spread spectrum sent by the terminal 100. The Beidou network device 200 can despread the received spread spectrum modulated data (spread+modulateddata) to obtain modulated data (modulateddata). Then, the Beidou network device 200 can demodulate the modulated data to obtain pilot coded data (pilot+data). Next, the Beidou network device 200 removes the pilot information in the pilot coded data to obtain coded data (codedata). Then, the Beidou network device 200 can decode the coded data and verify the integrity of the coded block (codeblock) through the check data in the check bit field. If complete, the Beidou network device 200 can extract the coded block (codeblock) and present it to the SLC layer through the inter-layer interface as the SLC PDU of the SLC layer.

[0160] At the SLC layer, the BeiDou network device 200 can concatenate SLC PDUs belonging to the same SLC SDU into one SLC SDU based on the frame header information of the SLC PDU. The BeiDou network device 200 can present the SLC SDU to the MDCP layer through the inter-layer interface as an MDCP PDU of the MDCP layer.

[0161] At the MDCP layer, the BeiDou network device 200 can concatenate all MDCP PDUs belonging to the same MDCP SDU into one MDCP SDU. The BeiDou network device 200 can present the MDCP SDU to the APP layer through the inter-layer interface as an application layer message received by the APP layer.

[0162] At the APP layer, the Beidou network device 200 can decrypt and decompress the application layer message based on the message header of the application layer message to obtain the original data.

[0163] In the embodiments of the present application, the above-mentioned protocol processing process is only an example, and the present application does not limit the specific operations of the protocol processing.

[0164] The following describes a protocol encapsulation architecture for outbound data of a Beidou communication system 10 provided in an embodiment of the present application.

[0165] Figure 5A A schematic diagram of a protocol encapsulation architecture for outbound data of a Beidou communication system 10 provided in an embodiment of the present application is shown.

[0166] like Figure 5A As shown, the BeiDou short message transmission protocol layer in the BeiDou network device 200 can be an application layer protocol, a message data convergence protocol (MDCP), a satellite link control protocol (SLC), and a physical layer protocol (PHY). Among them, the BeiDou network device 200 can include a BeiDou ground transceiver station 22, a BeiDou central station 23, and a BeiDou short message fusion communication platform 24. The BeiDou ground transceiver station 22 can be used to be responsible for the protocol processing of the PHY layer. The BeiDou central station 23 can be used to be responsible for the protocol processing of the SLC layer and the MDCP layer. The BeiDou short message fusion communication platform 24 can be used to be responsible for the protocol processing of the APP layer.

[0167] When the Beidou network device 200 sends data to the terminal 100, the workflow of the Beidou short message transmission protocol in the Beidou network device 200 may be as follows:

[0168] At the APP layer, the Beidou network device 200 may compress the original data into compressed data using a compression algorithm and add a compression indicator field to the front of the compressed data. The compression indicator field may be used to indicate the compression algorithm type used for the compressed data. The Beidou network device 200 may then encrypt the compressed data to obtain encrypted data and add an encryption algorithm field to the header of the encrypted data. The encryption algorithm field indicates the encryption algorithm type used for the encrypted data. The Beidou network device 200 may encapsulate the encrypted data, the compression indicator field, and the encryption indicator field into an application layer message and send it to the MDCP layer. The application layer message may include a message header and message data. The message header may include a compression indicator field and an encryption indicator field, among other fields. The message data includes the encrypted data.

[0169] Optionally, the Beidou network device 200 may also encrypt the compression indication field and the compressed data together to obtain encrypted data.

[0170] At the MDCP layer, the Beidou network device 200 can obtain the application layer message sent by the APP layer through the inter-layer interface and use the application layer message as an MDCP SDU. At the MDCP layer, the Beidou network device 200 can split an MDCP SDU into one or more fixed-length MDCP segment data (M_segement) and add a successor indication field to the header of each MDCP segment data to obtain an MDCP PDU. That is, the MDCP PDU includes an M_segement and a successor indication field. The successor indication field can be used to indicate whether the current MDCP PDU is the starting MDCP PDU, an intermediate MDCP PDU, or the last MDCP PDU of multiple MDCP PDUs sent continuously; or a single MDCP PDU sent separately.

[0171] At the SLC layer, the BeiDou network device 200 can obtain the MDCP PDU sent by the MDCP layer through the inter-layer interface as an SLC SDU. At the SLC layer, the BeiDou network device 200 can segment the SLC SDU into one or more (for example, up to 4) fixed-length SLC segments (S_segement) and add frame header information to the header of each S_segement to obtain an SLC PDU.

[0172] Here, it is understood that in order to adapt to the frame length of the physical layer, the SLC layer needs to segment the data. However, the SLC layer is designed to divide an SLC SDU into a maximum of N (for example, N is 4) SLC PDUs, so the MDCP layer also needs to segment the data.

[0173] At the PHY layer, the Beidou network device 200 can obtain the SLC PDU sent by the SLC layer through the inter-layer interface. The Beidou network device 200 can obtain the SLC PDU of one or more users from the SLC layer. The Beidou network device 200 can splice the SLC PDUs of multiple users together, add the frame header of the physical frame (such as the version number) as the coding block (code block) of the PHY layer, and add a check bit (for example, a cyclic redundancy check (CRC) code) at the end of the code block, and encode the code block and CRC code (for example, polar coding). The encoded physical frame plus the reserved segment can form a fixed-length physical time slot satellite to user end data (satellite to consumer data, S2C-d) channel branch (abbreviated as data branch or message branch) coded data. Among them, the Beidou network device 200 can put multiple SLC PDUs of a user into different physical frames respectively. Then, the BeiDou network device 200 combines the coded data of the S2C-d channel branch and the pilot information of the satellite-to-consumer pilot (S2C-p) branch (hereinafter referred to as the pilot branch) to form pilot coded data, i.e., outbound data. The BeiDou network device 200 can send the outbound data to the BeiDou short message satellite 21, which is then relayed to the terminal 100 via the BeiDou short message satellite 21.

[0174] It is understood that the pilot information of the S2C-p branch is related to the satellite beam. When the satellite beam number is known, the pilot information (i.e., the secondary code) of the S2C-p branch is also known and does not require decoding. However, the encoded data of the S2C-d branch requires decoding. The S2C-p channel and the S2C-d channel have the same center frequency and bandwidth, and the signals on the S2C-p channel and the S2C-d channel are mutually orthogonal.

[0175] The time length of the physical timeslot may be 125 ms, the time length of the physical frame may be 114 ms, and the time length of the reserved segment may be 11 ms.

[0176] In the embodiments of the present application, this is only an example, and the present application does not limit the specific operations of the PHY layer.

[0177] The following describes a protocol parsing architecture for outbound data of a Beidou communication system 10 provided in an embodiment of the present application.

[0178] Figure 5B A schematic diagram of a protocol parsing architecture for outbound data of a Beidou communication system 10 provided in an embodiment of the present application is shown.

[0179] like Figure 5B As shown, the Beidou short message transmission protocol layer of the terminal 100 can be divided into an application layer (application layer protocol), a message data convergence protocol (MDCP), a satellite link control protocol (SLC) and a physical layer (PHY).

[0180] When the terminal 100 receives data sent by the Beidou network device, the workflow of the Beidou short message transmission protocol layer of the terminal 100 can be as follows:

[0181] At the PHY layer, the terminal 100 can obtain the pilot coded data after modulation and spread spectrum sent by the Beidou network device 200. The terminal 100 can despread the received spread spectrum modulated data (spread+modulated data) to obtain modulated data (modulated data). Then, the terminal 100 can demodulate the modulated data to obtain pilot coded data (pilot+data). Then, the terminal 100 can remove the pilot information in the pilot coded data to obtain coded data (code data). Then, the terminal 100 can decode the coded data and verify the integrity of the code block (code block) through the check data in the check bit field. If complete, the terminal 100 can extract the code block (code block) and present it to the SLC layer through the inter-layer interface as the SLC PDU of the SLC layer.

[0182] Here, the pilot coded data is the outbound data sent by the Beidou network device 200, and the outbound data consists of the coded data of the S2C-d channel and the pilot information of the S2C-p channel.

[0183] At the SLC layer, the terminal 100 can concatenate SLC PDUs belonging to the same SLC SDU into one SLC SDU based on the frame header information of the SLC PDU. The terminal 100 can present the SLC SDU to the MDCP layer through the inter-layer interface as an MDCP PDU of the MDCP layer.

[0184] At the MDCP layer, the terminal 100 may concatenate all MDCP PDUs belonging to the same MDCP SDU into one MDCP SDU. The terminal 100 may present the MDCP SDU to the APP layer via an inter-layer interface as an application layer message received by the APP layer.

[0185] At the APP layer, the terminal 100 may decrypt and decompress the application layer message based on the message header of the application layer message to obtain the original data.

[0186] In the embodiments of the present application, the above-mentioned protocol processing process is only an example, and the present application does not limit the specific operations of the protocol processing.

[0187] In the Beidou communication system 10, the capacity of each beam in the outbound link is 2 kbit / s, and even when the S2C-d channel branch of the outbound link is good, it can only reach 4 kbit / s. In the Beidou communication system 10 that supports 18 beams, the total outbound link capacity of the entire system is only 40 kbit / s at best in the areas where the beams overlap. Because the current Beidou communication system lacks a separate control channel, all terminals share the outbound link of the Beidou communication system 10, requiring high frame header overhead to schedule outbound resources for different terminals.

[0188] When the data volume of a single inbound message is different, the number of messages that the inbound link can accommodate per second can be shown in the following Table 1:

[0189] Table 1

[0190]

[0191]

[0192] As can be seen from Table 1 above, one Chinese character can be represented by 16 bits of data.

[0193] 1. When a single inbound message contains 100 Chinese characters, the data size is 1600 bits. Using an inbound universal data frame with a data length of 512 bits, a single message uses four universal data frames, resulting in a total inbound resource usage of 2048 bits. The control field overhead (including frame header overhead, packet header overhead, message header overhead, and check bit overhead) used by a single message is 447 bits, and the data payload used by a single message is 1601 bits. A single beam can support 46.18 inbound messages per second.

[0194] 2. When a single inbound message contains 48 Chinese characters, the data size of the single inbound message is 768 bits. When using an inbound universal data frame with a data length of 512 bits, a single message uses two universal data frames, so the inbound resource usage of a single message is 1024 bits. Of this, the control field overhead (including frame header overhead, packet header overhead, message header overhead, and check bit overhead) used by a single message is 249 bits, and the data payload used by a single message is 775 bits. A single beam can support 92.36 inbound messages per second.

[0195] 3. When a single inbound message contains 22 Chinese characters, the data size of the single inbound message is 352 bits. When using an inbound universal data frame with a data length of 512 bits, the data size of a single message is 1 universal data frame, so the inbound resource usage of a single message is 512 bits. The control field overhead (including frame header overhead, packet header overhead, message header overhead, and check bit overhead) used by a single message is 150 bits, and the data payload used by a single message is 362 bits. A single beam can support 184.72 inbound messages per second.

[0196] However, in a 2kbit / s outbound link, excluding the 11ms reserved portion of each 125ms physical transmission time slot, the actual outbound physical frame duration is only 114ms. Excluding the check bit, the user-usable data in the outbound physical frame is only approximately 200 bits. The SLC layer user frame header overhead is 56 bits. For ACK frames, the data portion contains only 4 bits. Even if the entire outbound physical frame is used for ACK frames, a single outbound physical frame can only carry a maximum of 3 ACK frames. Every second, the Beidou network device 200 can send 8 physical frames in a single beam. Therefore, the Beidou network device 200 can only support the feedback of 24 ACK frames per second on a single beam, which in most scenarios is less than the number of inbound messages per second on a single beam. This results in the Beidou network device 200 being unable to promptly feedback ACK frames to the terminal that sent the inbound message, resulting in low transmission efficiency on the outbound link.

[0197] Therefore, an embodiment of the present application provides a compact feedback method in a Beidou communication system, which can implement a feedback frame in a compact data packet (Cpack) format (e.g., a CpackACK frame, a Cpack receipt frame) on the basis of a feedback frame in an Apack format. Compared with the frame header of the feedback frame in the Apack format, the frame header of the Cpack format feedback frame has a compressed data volume, thereby improving the transmission efficiency of the outbound link.

[0198] The following describes a set of outbound user frames provided in an embodiment of the present application.

[0199] Figure 6A An outbound general data frame provided by an embodiment of the present application is shown.

[0200] like Figure 6AAs shown, the universal data frame when outbound may include a universal data frame header and user information. Among them, the user information is used to carry the outbound message data sent by the Beidou network device 200. The universal data frame header may include a start identifier field, a frame type field, a frame length field, a user ID field, a total number of frames field and a frame sequence number field. Among them,

[0201] The start identification field can be used to identify the starting position of the general data frame, wherein the data length of the start identification field can be 8 bits.

[0202] The frame type field can be used to indicate the frame type of the general data frame. The data length of the frame type field can be 2 bits, and the frame types of the outbound user frame can include general data frame, ACK frame and receipt frame.

[0203] The value and meaning of the frame type field may be shown in Table 2 below:

[0204] Table 2

[0205] The value of the frame type field meaning 00 Generic Data Frame 01 ACK frame 10 Receipt frame 11 Reserved (RSV)

[0206] As can be seen from Table 2 above, the frame type indicated by the value of "00" in the frame type field is a general data frame. The frame type indicated by the value of "01" in the frame type field is an ACK frame. The frame type indicated by the value of "10" in the frame type field is a receipt frame. The frame type field value of "11" is a reserved (RSV) value. Table 2 above is only used to explain this application and should not constitute a limitation. In a specific implementation, there may be more or fewer frame types. Therefore, the data length of the frame type field may be longer or shorter.

[0207] The frame length field indicates the length of user information in a general data frame. When the outbound S2C-d channel transmission rate is 2 kbit / s, the frame length field can be 8 bits; when the outbound S2C-d channel transmission rate is 4 kbit / s, the frame length field can be 9 bits.

[0208] The user ID field can be used to indicate the device identification of the receiving terminal of the universal data frame. The data length of the user ID field can be 34 bits.

[0209] If the terminal 100 parses the physical frame transmitted by the S2C-d channel branch of the Beidou network device 200 and finds a user frame whose user ID field is the same as the user ID of the terminal 100, the terminal 100 can identify the frame type of the user frame. If the frame type of the user frame is a general data frame, the terminal 100 can frame the general data frame as the SLC PDU of the SLC layer, and the SLC SDU obtained after framing is presented from the SLC layer to the MDCP layer through the inter-layer interface, and packaged at the MDCP layer. Among them, for the process of the terminal 100 framing at the SLC layer and packaging at the MDCP layer, please refer to the aforementioned Figure 5B The embodiments shown will not be described in detail here.

[0210] The total number of frames field may be used to indicate the total number of general data frames in the SLC session in which the general data frame resides. When the maximum number of general data frames in the SLC session is 4, the total number of frames may have a data length of 2 bits.

[0211] The frame sequence number field may be used to indicate the frame sequence number of the general data frame in an SLC session. When the maximum number of general data frames in an SLC session is 4, the data length of the frame sequence number field may be 2 bits.

[0212] In some embodiments, the above-mentioned general data frame header may also include an acknowledgment mode enable (AMenable) field, wherein the AM enable field in the general data frame header can be used to indicate whether the terminal 100 adopts the acknowledgment mode or the non-acknowledgment mode at the SLC layer to receive the general data frame sent by the Beidou network device 200.

[0213] Figure 6B An outbound complete (Apack) format ACK frame provided in an embodiment of the present application is shown.

[0214] like Figure 6B As shown, the ACK frame in the Apack format (abbreviated as Apack ACK frame) may include an ApackACK frame header and an ACK field. The ApackACK frame header may include a start identifier field, a frame type field, and a user ID field.

[0215] The start identifier field can be used to identify the starting position of the Apack ACK frame.

[0216] The Frame Type field can be used to indicate the frame type of the APPACK frame. The data length of the Frame Type field can be 2 bits. The frame types of user frames can include general data frames, APPACK frames, and receipt frames. The meaning of each value in the Frame Type field can be referred to in Table 2 above and will not be repeated here.

[0217] The user ID field can be used to indicate the device identification of the receiving terminal of the APPACK frame. The data length of the user ID field can be 34 bits.

[0218] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0219] Figure 6C An outbound receipt frame provided in an embodiment of the present application is shown.

[0220] like Figure 6C As shown, the receipt frame may include a receipt frame header and receipt information. The receipt frame header may include a start identifier field, a frame type field, and a user ID field.

[0221] The start identification field can be used to indicate the starting position of the receipt frame.

[0222] The Frame Type field indicates the frame type of the Receipt Frame. The Frame Type field may have a data length of 2 bits. Outbound user frames may include General Data Frames, ApackACK Frames, and Receipt Frames. The meaning of each value in the Frame Type field can be found in Table 2 above and is not further detailed here.

[0223] The user ID field can be used to indicate the device identification of the receiving terminal of the receipt frame. The data length of the user ID field can be 34 bits.

[0224] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0225] Figure 6D An outbound compact (Cpack) format ACK frame provided in an embodiment of the present application is shown.

[0226] like Figure 6DAs shown, the ACK frame in the Cpack format (abbreviated as Cpack ACK frame) may include a CpackACK frame header and an ACK field. The CpackACK frame header may include a frame type field and a user CID field.

[0227] The User CID field may be used to indicate the compact device identifier of the receiver of the CpackACK frame. The data length of the User CID field may be 8 bits.

[0228] The value of the user CID field may be the last 8 bits of the user ID of the receiver of the universal data frame in the Cpack format.

[0229] In one possible implementation, the Beidou network device 200 can determine the user CID value based on the user ID carried in the data request frame sent by the recipient of the Cpack format universal data frame (such as the terminal 100) and the specified data information in the data request frame.

[0230] For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the last 16 bits of data in the data portion of the data request frame to obtain an 8-bit user CID.

[0231] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0232] Based on the above Figures 6A-6D A group of outbound user frames is shown, introducing the process of the Beidou network device 200 scheduling user frames in the outbound physical frames and the process of the terminal 100 parsing user frames from the outbound physical frames in an embodiment of the present application.

[0233] Figure 7 The user frame scheduling process provided in an embodiment of the present application is shown.

[0234] like Figure 7 As shown, the Beidou network device 200 can send an outbound physical frame on the S2C-d channel branch. The outbound physical frame may have a duration of 114ms and a transmission rate of 2kbit / s or 4kbit / s on the S2C-d channel branch.

[0235] An outbound physical frame may include a physical frame header, one or more user frames, and a check bit. The physical frame header may include a version number. This version number may be used to indicate the version of the physical frame format currently used by the Beidou network device 200. User frames scheduled by the Beidou network device 200 in the outbound physical frame may include an Apack ACK frame, a Cpack ACK frame, a receipt frame, and a general data frame.

[0236] For example, the outbound physical frame may include a Cpack ACK frame sent to the terminal 100 , a receipt frame sent to the terminal 400 , a general data frame sent to the terminal 500 , and an Apack ACK frame sent to the terminal 600 .

[0237] The process of the terminal 100 parsing the outbound physical frame to obtain the user frame sent to the terminal 100 may be as follows:

[0238] 1. The terminal 100 may identify a physical frame header in an outbound physical frame at a PHY layer, wherein the physical frame header may include a version number field, and the data length of the version number field is 3 bits.

[0239] 2. When terminal 100 decodes an outbound physical frame on the S2C-d channel branch at the PHY layer, it can sequentially decode the frame using transmission rates of 2 kbit / s and 4 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 2 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 2 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 4 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 4 kbit / s. Therefore, after terminal 100 successfully decodes the outbound physical frame at the PHY layer, it can present the transmission rate on the S2C-d channel branch from the PHY layer to the SLC layer for use in determining the data length of the frame length field in the universal data frame when the SLC layer parses the user frame in the outbound physical frame. When the transmission rate on the S2C-d channel branch is 2 kbit / s, the data length of the frame length field in the universal data frame is 8 bits. When the transmission rate on the S2C-d channel branch is 4 kbit / s, the data length of the frame length field in the general data frame is 9 bits.

[0240] In the embodiment of the present application, the process of parsing the user frame from the outbound physical frame by the terminal 100 is described by taking the transmission rate on the S2C-d channel branch as 2 kbit / s and the data length of the frame length field in the general data frame as 8 bits as an example.

[0241] 3. Since the length of the start identifier field in a complete frame is 8 bits, and the value of the start identifier field is a preset value, for example, the value of the start identifier field is "01111110", terminal 100 can determine whether the 8-bit data immediately following the physical frame header in the outbound physical frame is the same as the value of the start identifier field. If so, terminal 100 can determine that the first user frame immediately following the physical frame header in the outbound physical frame is a complete frame. Frame types of complete frames include general data frames, ApackACK frames, and receipt frames.

[0242] When the first user frame is a complete frame, the terminal 100 may further determine the frame type of the first user frame based on the frame type field in the first user frame.

[0243] (1) If the first user frame is a general data frame, the terminal 100 can determine whether the user ID field of the first user frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the first user frame is a general data frame sent to the terminal 100. The terminal 100 can frame the general data frame as an SLC PDU at the SLC layer and package it at the MDCP layer, and finally present the packaged MDCP SDU as an application layer message from the MDCP layer to the application layer. If the user ID field of the general data frame is not the same as the user ID of the terminal 100, the terminal 100 discards the general data frame and continues to parse subsequent user frames in the outbound physical frame.

[0244] The data length of the universal data frame header can be a fixed value, for example, 56 bits. The value of the frame length field in the universal data frame header is used to indicate the data length of the user information in the universal data frame, for example, X bits. Therefore, terminal 100 can determine that the total data length of the universal data frame is (56+X) bits.

[0245] (2) If the first user frame is an Apack ACK frame, the terminal 100 can determine whether the value of the user ID field of the Apack ACK frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the Apack ACK frame is the terminal 100 and parse the ACK bitmap of the Apack ACK frame. If the value of the user ID field of the Apack ACK frame is not the same as the user ID of the terminal 100, the terminal 100 discards the Apack ACK frame and continues to parse subsequent user frames in the outbound physical frame.

[0246] The total data length of the Apack ACK frame is a fixed value, for example, 44 bits.

[0247] (3) If the first user frame is a receipt frame, the terminal 100 can determine whether the value of the user ID field of the receipt frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the receipt frame is the terminal 100 and parse the receipt information of the receipt frame; if the value of the user ID field of the receipt frame is not the same as the user ID of the terminal 100, the terminal 100 discards the receipt frame and continues to parse the subsequent user frames in the outbound physical frame.

[0248] The total data length of the receipt frame is a fixed value, for example, 44 bits.

[0249] If terminal 100 can determine that the 8-bit data immediately following the physical frame header in the outbound physical frame is different from the value of the start identifier field, terminal 100 can determine that the first user frame is a Cpack ACK frame, and the 8-bit data immediately following the physical frame header in the outbound physical frame is the user CID field in the Cpack ACK frame. Terminal 100 can further determine whether the value of the user CID field in the Cpack ACK frame is the same as the user CID of terminal 100. If they are the same, terminal 100 can determine that the recipient of the Cpack ACK frame is terminal 100. If the value of the user CID field in the Cpack ACK frame is different from the user CID of terminal 100, terminal 100 can determine that the recipient of the Cpack ACK frame is another terminal, discard the Cpack ACK frame, and continue to parse subsequent user frames in the outbound physical frame.

[0250] The total data length of the Cpack ACK frame is a fixed value, for example, 12 bits.

[0251] 4. After determining the total data length of the first user frame, the terminal 100 may determine the position of the frame header of the second user frame in the outbound physical frame based on the total data length of the first user frame.

[0252] 5. After determining the frame type of the second user frame, the terminal 100 may parse the frame header of the second user frame based on the frame format corresponding to the frame type, and determine the total data length of the second user frame.

[0253] 6. After determining the data length of the entire second user frame, the terminal 100 may determine the position of the frame header of the third user frame in the outbound physical frame based on the total data length of the second user frame.

[0254] The parsing process of the terminal 100 for the second user frame and subsequent user frames in the outbound physical frame may refer to the parsing process for the first user frame in the outbound physical frame, which will not be repeated here.

[0255] In one possible implementation, after generating an initial user CID for terminal 100, if Beidou network device 200 determines that the initial user CID of terminal 100 is the same as the starting identifier, Beidou network device 200 may modify the user CID, where the modified user CID is different from the starting identifier. The user CID field in the CpackACK frame carries the modified user CID.

[0256] For example, the initial user CID may be "01111110" and the starting identifier may be "01111110". If the initial user CID and the starting identifier overlap, the Beidou network device 200 may add "1" to the last bit of the initial user CID to obtain a corrected user CID. The corrected user CID may be "01111111".

[0257] The value of the initial user CID field may be the last 8 bits of the receiver ID of the Cpack ACK frame.

[0258] In one possible implementation, the Beidou network device 200 may determine an initial user CID value based on the user ID carried in the data request frame sent by the recipient of the Cpack format user frame (e.g., terminal 100) and the specified data information in the data request frame. For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the specified data information in the data request frame to obtain an 8-bit initial user CID.

[0259] For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the last 16 bits of data in the data portion of the data request frame to obtain an 8-bit initial user CID.

[0260] Among them, the process of terminal 100 calculating the initial user CID of terminal 100 and the process of terminal 100 correcting the initial user CID can refer to the process of Beidou network device 200 calculating the initial user CID of terminal 100 and the process of correcting the initial user CID, which will not be repeated here.

[0261] Another set of outbound user frames provided in an embodiment of the present application is introduced below.

[0262] Figure 8A An outbound general data frame provided in an embodiment of the present application is shown.

[0263] like Figure 8AAs shown, the outbound universal data frame may include a universal data frame header and user information. The user information is used to carry the outbound message data sent by the Beidou network device 200. The universal data frame header may include a frame type field, a frame length field, a user ID field, a total number of frames field, and a frame sequence number field.

[0264] The frame type field can be used to indicate the frame type of the general data frame. The data length of the frame type field can be 2 bits, and the frame types of outbound user frames can include general data frames, ACK frames, receipt frames, and flexible feedback frames.

[0265] The value and meaning of the frame type field may be shown in Table 3 below:

[0266] Table 3

[0267] The value of the frame type field meaning 00 Generic Data Frame 01 Normal ACK frame 10 Normal receipt frame 11 Flexible Feedback Frame

[0268] It can be seen from Table 3 above that the frame type indicated by the value of "00" in the frame type field is a general data frame. The frame type indicated by the value of "01" in the frame type field is a normal ACK frame. The frame type indicated by the value of "10" in the frame type field is a normal receipt frame. The frame type indicated by the value of "11" in the frame type field is a flexible feedback frame, wherein the flexible feedback frame may include a stop-wait Apack ACK frame, a stop-wait Cpack ACK frame, a parallel Apack ACK frame, a parallel Cpack ACK frame, an Apack receipt frame, and a Cpack receipt frame. Table 3 above is only used to explain this application and should not constitute a limitation. In a specific implementation, there may be more or fewer frame types, and therefore, the data length of the frame type field may be longer or shorter.

[0269] The frame length field indicates the length of user information in a general data frame. When the outbound S2C-d channel transmission rate is 2 kbit / s, the frame length field can be 8 bits; when the outbound S2C-d channel transmission rate is 4 kbit / s, the frame length field can be 9 bits.

[0270] The user ID field can be used to indicate the device identification of the receiving terminal of the universal data frame. The data length of the user ID field can be 34 bits.

[0271] The total number of frames field may be used to indicate the total number of general data frames in the SLC session in which the general data frame resides. When the maximum number of general data frames in the SLC session is 4, the total number of frames may have a data length of 2 bits.

[0272] The frame sequence number field may be used to indicate the frame sequence number of the general data frame in an SLC session. When the maximum number of general data frames in an SLC session is 4, the data length of the frame sequence number field may be 2 bits.

[0273] In some embodiments, the above-mentioned general data frame header may further include an AMenable field, wherein the AM enable field in the general data frame header can be used to indicate whether the terminal 100 adopts confirmation mode or non-confirmation mode at the SLC layer to receive the general data frame sent by the Beidou network device 200.

[0274] Figure 8B An outbound ACK frame provided in an embodiment of the present application is shown.

[0275] like Figure 8B As shown, the ACK frame may include an ACK frame header and an ACK field. The ACK frame header may include a frame type field and a user ID field.

[0276] The Frame Type field indicates the frame type of the ACK frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be found in Table 3 above and is not further described here.

[0277] The user ID field can be used to indicate the device identification of the receiving terminal of the ACK frame. The data length of the user ID field can be 34 bits.

[0278] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0279] Figure 8C An outbound receipt frame provided in an embodiment of the present application is shown.

[0280] like Figure 8C As shown, the receipt frame may include a receipt frame header and receipt information. The receipt frame header may include a frame type field and a user ID field. The frame type field indicates the frame type of the receipt frame. The data length of the frame type field may be 2 bits, and the frame types of outbound user frames may include general data frames, ACK frames, and receipt frames. The meaning of each value in the frame type field can be referred to in Table 3 above and will not be further described here.

[0281] The user ID field can be used to indicate the device identification of the receiving terminal of the receipt frame. The data length of the user ID field can be 34 bits.

[0282] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0283] Figure 8D-Figure 8I A set of outbound flexible feedback frames provided in an embodiment of the present application is shown.

[0284] The subtypes of the flexible feedback frame may include a stop-and-wait Apack ACK frame, a stop-and-wait Cpack ACK frame, a parallel Apack ACK frame, a parallel Cpack ACK frame, an Apack receipt frame, and a Cpack receipt frame.

[0285] Figure 8D A stop-and-wait Apack ACK frame provided in an embodiment of the present application is shown.

[0286] like Figure 8D As shown, the stop-wait Apack ACK frame includes a stop-wait Apack ACK frame header and feedback information. The stop-wait Apack ACK frame header may include a frame type field and a frame length field, with the frame type field being located before the frame length field. The feedback information may include a user ID field.

[0287] The Frame Type field can be used to indicate the frame type of the Stop Wait ACK frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be referred to in Table 3 above and will not be repeated here.

[0288] The frame length field can be used to indicate the data length of the feedback information. The frame length field can be 6 bits long. Since the feedback information of the stop-wait Apack ACK frame only includes the user ID field, the value of the frame length field in the stop-wait Apack ACK frame is the data length of the user ID field.

[0289] The User ID field can be used to indicate the device identification of the receiving terminal of the Stop Wait Apack ACK frame. Among them, the value of the User ID field is 34 bits, and the value of the Frame Length field in the Stop Wait Apack ACK frame is "100010".

[0290] In an embodiment of the present application, when the total number of frames indicated by the total number of frames field in the frame header of the SLC PDU sent by the terminal 100 to the Beidou network device 200 is "1", it means that after the terminal 100 sends an SLC PDU to the Beidou network device 200, the Beidou network device 200 needs to feedback the reception status of the single SLC PDU. Therefore, the ACK bitmap portion can be omitted from the ACK frame returned by the Beidou network device 200. When the terminal 100 does not support the Cpack confirmation mode and the total number of frames indicated by the total number of frames field in the SLC PDU sent by the terminal 100 is "1", the Beidou network device 200 can return the waiting APPACK frame to the terminal 100 after receiving the single SLC PDU sent by the terminal 100.

[0291] Figure 8E A stop-and-wait Cpack ACK frame provided in an embodiment of the present application is shown.

[0292] like Figure 8E As shown, the Cpack ACK frame includes a Cpack ACK frame header and feedback information. The Cpack ACK frame header may include a frame type field and a frame length field, with the frame type field located before the frame length field. The feedback information may include a user CID field.

[0293] The Frame Type field can be used to indicate the frame type of the Stop-Wait Cpack ACK frame. The Frame Type field can have a data length of 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be found in Table 3 above and is not further described here.

[0294] The frame length field can be used to indicate the data length of the feedback information. The frame length field can be 6 bits long. Since the feedback information of the Stop-Wait Cpack ACK frame only includes the User CID field, the value of the frame length field in the Stop-Wait Apack ACK frame is the data length of the User CID field.

[0295] The User CID field can be used to indicate the compact device identifier of the receiving terminal of the Stop-Wait Cpack ACK frame. Among them, the value of the User CID field is 8 bits, and the value of the frame length field in the Stop-Wait Cpack ACK frame is "000100". For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0296] In this embodiment of the present application, when the total number of frames indicated by the total number of frames field in the frame header of the SLC PDU sent by terminal 100 to Beidou network device 200 is "1", it means that after terminal 100 sends an SLC PDU to Beidou network device 200, Beidou network device 200 needs to feedback the reception status of this single SLC PDU. Therefore, the ACK bitmap portion can be omitted from the ACK frame returned by Beidou network device 200. When terminal 100 supports Cpack acknowledgment mode and the total number of frames indicated by the total number of frames field in the SLC PDU sent by terminal 100 is "1", Beidou network device 200 can return the waiting Cpack ACK frame to terminal 100 after receiving the single SLC PDU sent by terminal 100.

[0297] Figure 8F A parallel Apack ACK frame provided in an embodiment of the present application is shown.

[0298] like Figure 8F As shown, the parallel APPACK ACK frame includes a parallel APPACK ACK frame header and feedback information. The parallel APPACK ACK frame header may include a frame type field and a frame length field, and the frame type field is located before the frame length field. The feedback information may include a user ID field and an ACK field.

[0299] The Frame Type field can be used to indicate the frame type of the parallel APPACK ACK frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be referred to in Table 3 above and will not be repeated here.

[0300] The frame length field can be used to indicate the data length of the feedback information. The data length of the frame length field can be 6 bits. Since the feedback information of the parallel APPACK frame only includes the user ID field and the ACK field, the value of the frame length field in the parallel APPACK frame is the sum of the data lengths of the user ID field and the ACK field.

[0301] The User ID field can be used to indicate the device identification of the receiving terminal of the parallel APPack ACK frame. The value of the User ID field is 34 bits.

[0302] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0303] Therefore, the sum of the data lengths of the user ID field and the ACK field is 38 bits, and the value of the frame length field in the parallel Apack ACK frame is "100110".

[0304] In an embodiment of the present application, the terminal 100 can continuously send N SLC PDUs to the Beidou network device 200, and then receive the reception status of the N SLC PDUs fed back by the Beidou network device 200, wherein the ACK bitmap in the ACK frame returned by the Beidou network device 200 is used to indicate the reception status of the Beidou network device 200 for the N SLC PDUs. The data length of the ACK bitmap is the maximum value of N (for example, 4). When N is less than the data length of the ACK bitmap, the N bits at the specified position in the ACK bitmap can be used to indicate the reception status of the Beidou network device 200 for the N SLC PDUs. When the terminal 100 does not support the Cpack confirmation mode, the Beidou network device 200 can return the parallel Apack ACK frame to the terminal 100 after receiving M SLC PDUs out of the N SLC PDUs sent by the terminal 100, wherein M is less than or equal to N, and M and N are positive integers.

[0305] Figure 8G A parallel Cpack ACK frame provided in an embodiment of the present application is shown.

[0306] like Figure 8G As shown, the parallel Cpack ACK frame includes a parallel Cpack ACK frame header and feedback information. The parallel Cpack ACK frame header may include a frame type field and a frame length field, and the frame type field is located before the frame length field. The feedback information may include a user CID field and an ACK field.

[0307] The Frame Type field can be used to indicate the frame type of the parallel Cpack ACK frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be referred to in Table 3 above and will not be repeated here.

[0308] The frame length field can be used to indicate the data length of the feedback information. The frame length field can be 6 bits long. Since the feedback information of the parallel Cpack ACK frame only includes the user CID field and the ACK field, the value of the frame length field in the parallel Cpack ACK frame is the sum of the data lengths of the user CID field and the ACK field.

[0309] The User CID field can be used to indicate the compact device identifier of the receiving terminal of the parallel Cpack ACK frame. The value of the User CID field is 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0310] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0311] Therefore, the sum of the data lengths of the user CID field and the ACK field is 12 bits, and the value of the frame length field in the parallel Apack ACK frame is "001100".

[0312] In an embodiment of the present application, the terminal 100 can continuously send N SLC PDUs to the Beidou network device 200, and then receive the reception status of the N SLC PDUs fed back by the Beidou network device 200, wherein the ACK bitmap in the ACK frame returned by the Beidou network device 200 is used to indicate the reception status of the Beidou network device 200 for the N SLC PDUs. The data length of the ACK bitmap is the maximum value of N (for example, 4). When N is less than the data length of the ACK bitmap, the N bits at the specified position in the ACK bitmap can be used to indicate the reception status of the Beidou network device 200 for the N SLC PDUs. When the terminal 100 supports the Cpack confirmation mode, the Beidou network device 200 can return the parallel Cpack ACK frame to the terminal 100 after receiving M SLC PDUs out of the N SLC PDUs sent by the terminal 100, wherein M is less than or equal to N, and M and N are positive integers.

[0313] Figure 8H An Apack receipt frame provided in an embodiment of the present application is shown.

[0314] like Figure 8HAs shown, the Apack receipt frame includes an Apack receipt frame header and feedback information. The Apack receipt frame header may include a frame type field and a frame length field, and the frame type field is located before the frame length field. The feedback information may include a user ID field, an ACK field, and receipt information.

[0315] The Frame Type field can be used to indicate the frame type of the APPACK Receipt frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be referred to in Table 3 above and will not be repeated here.

[0316] The frame length field can be used to indicate the data length of the feedback information. The data length of the frame length field can be 6 bits. Since the feedback information of the Apack receipt frame only includes the user ID field, ACK field, and receipt information, the value of the frame length field in the Apack receipt frame is the sum of the data lengths of the user ID field, ACK field, and receipt information.

[0317] The User ID field can be used to indicate the device identification of the receiving terminal of the APPACK receipt frame. The value of the User ID field is 34 bits.

[0318] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0319] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0320] Therefore, the sum of the data lengths of the user ID field, ACK field, and receipt information is 42 bits, and the value of the frame length field in the Apack receipt frame is "101010".

[0321] In an embodiment of the present application, after the Beidou network device 200 receives all SLC PDUs in the first application layer message sent by the terminal 100, the Beidou network device 200 can generate a first application layer message at the APP layer through the framing and packetization process for all SLC PDUs in the first application layer message, and parse the first application layer message at the APP layer. The Beidou network device 200 can feed back the parsing result of the first application layer message to the terminal 100 via a receipt frame at the SLC layer. In particular, when the terminal 100 does not support the Cpack confirmation mode, the Beidou network device 200 can receive the first application layer message sent by the terminal 100 and send an Apack receipt frame to the terminal 100 after parsing the first application layer message.

[0322] Figure 8I A Cpack receipt frame provided in an embodiment of the present application is shown.

[0323] like Figure 8I As shown, the Cpack receipt frame includes a Cpack receipt frame header and feedback information. The Cpack receipt frame header may include a frame type field and a frame length field, with the frame type field located before the frame length field. The feedback information may include a user CID field, an ACK field, and receipt information.

[0324] The Frame Type field can be used to indicate the frame type of the Cpack Receipt frame. The data length of the Frame Type field can be 2 bits. User frame types can include general data frames, ACK frames, receipt frames, and flexible feedback frames. The meaning of each value in the Frame Type field can be referred to in Table 3 above and will not be repeated here.

[0325] The frame length field can be used to indicate the data length of the feedback information. The frame length field can be 6 bits long. Since the feedback information of the Apack receipt frame only includes the user CID field, ACK field, and receipt information, the value of the frame length field in the Apack receipt frame is the sum of the user CID field, ACK field, and the data length of the receipt information.

[0326] The User CID field can be used to indicate the compact device identifier of the receiving terminal of the Cpack receipt frame. The value of the User CID field is 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0327] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an ACK bitmap, which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0328] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0329] Therefore, the sum of the data lengths of the user CID field, ACK field, and receipt information is 16 bits, and the value of the frame length field in the Cpack receipt frame is "010000".

[0330] In an embodiment of the present application, after the Beidou network device 200 receives all SLC PDUs in the first application layer message sent by the terminal 100, the Beidou network device 200 can generate a first application layer message at the APP layer through the framing and packetization processes for all SLC PDUs in the first application layer message, and parse the first application layer message at the APP layer. The Beidou network device 200 can feed back the parsing result of the first application layer message to the terminal 100 via a receipt frame at the SLC layer. Among them, when the terminal 100 supports the Cpack confirmation mode, the Beidou network device 200 can send a Cpack receipt frame to the terminal 100 after receiving the first application layer message sent by the terminal 100 and parsing the first application layer message.

[0331] Based on the above Figures 8A-8I A group of outbound user frames is shown, introducing the process of the Beidou network device 200 scheduling user frames in the outbound physical frames and the process of the terminal 100 parsing user frames from the outbound physical frames in an embodiment of the present application.

[0332] Figure 9 The user frame scheduling process provided in an embodiment of the present application is shown.

[0333] like Figure 9 As shown, the Beidou network device 200 can send an outbound physical frame on the S2C-d channel branch. The outbound physical frame may have a duration of 114ms and a transmission rate of 2kbit / s or 4kbit / s on the S2C-d channel branch.

[0334] The outbound physical frame may include a physical frame header, one or more user frames, and a check bit. The physical frame header may include a version number. The version number may be used to indicate the version of the physical frame format currently used by the Beidou network device 200.

[0335] When both feedback frames and general data frames are scheduled in an outbound physical frame, the scheduling order of the feedback frame in the outbound physical frame can be before the scheduling order of the general data frame, or the scheduling order of the feedback frame can be after the scheduling order of the general data frame. Among them, the feedback frame can include a normal ACK frame, a normal receipt frame, and a flexible feedback frame. Among them, the frame formats of the normal ACK frame, the normal receipt frame, and the flexible feedback frame can refer to the above Figure 8B-Figure 8I The embodiments shown will not be described in detail here.

[0336] For example, an outbound physical frame may include a flexible feedback frame sent to terminal 100, a normal receipt frame sent to terminal 400, a general data frame sent to terminal 500, and a normal ACK frame sent to terminal 600. The scheduling order from front to back may be: "flexible feedback frame sent to terminal 100 - normal receipt frame sent to terminal 400 - general data frame sent to terminal 500 - normal ACK frame sent to terminal 600".

[0337] The process of the terminal 100 parsing the outbound physical frame to obtain the user frame sent to the terminal 100 may be as follows:

[0338] 1. The terminal 100 may identify a physical frame header in an outbound physical frame at a PHY layer, wherein the physical frame header may include a version number field, and the data length of the version number field is 3 bits.

[0339] 2. When terminal 100 decodes an outbound physical frame on the S2C-d channel branch at the PHY layer, it can sequentially decode the frame using transmission rates of 2 kbit / s and 4 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 2 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 2 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 4 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 4 kbit / s. Therefore, after terminal 100 successfully decodes the outbound physical frame at the PHY layer, it can present the transmission rate on the S2C-d channel branch from the PHY layer to the SLC layer for use in determining the data length of the frame length field in the universal data frame when the SLC layer parses the user frame in the outbound physical frame. When the transmission rate on the S2C-d channel branch is 2 kbit / s, the data length of the frame length field in the universal data frame is 8 bits. When the transmission rate on the S2C-d channel branch is 4 kbit / s, the data length of the frame length field in the general data frame is 9 bits.

[0340] In the embodiment of the present application, the process of parsing the user frame from the outbound physical frame by the terminal 100 is described by taking the transmission rate on the S2C-d channel branch as 2 kbit / s and the data length of the frame length field in the general data frame as 8 bits as an example.

[0341] 3. Since the first field in the feedback frame header and the first field in the general data frame header are both 2-bit frame type fields, terminal 100 can determine the frame type of the first user frame based on the frame type field of the first user frame immediately following the physical frame header in the outbound physical frame.

[0342] (1) When the first user frame is a general data frame, terminal 100 can determine whether the user ID field of the general data frame is the same as the user ID of terminal 100. If they are, terminal 100 can determine that the recipient of the general data frame is terminal 100. Terminal 100 can frame the general data frame as an SLC PDU at the SLC layer and package it at the MDCP layer, and finally present the packaged MDCP SDU as an application layer message from the MDCP layer to the application layer. If the user ID field of the general data frame is not the same as the user ID of terminal 100, terminal 100 discards the general data frame and continues to parse subsequent user frames in the outbound physical frame.

[0343] The data length of the universal data frame header can be a fixed value, for example, 48 bits. The value of the frame length field in the universal data frame header is used to indicate the data length of the user information in the universal data frame, for example, X bits. Therefore, terminal 100 can determine that the total data length of the universal data frame is (48 + X) bits.

[0344] (2) When the first user frame is a normal ACK frame or a normal receipt frame, the terminal 100 can determine whether the value of the user ID field of the normal ACK frame or the normal receipt frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the normal ACK frame or the normal receipt frame is the terminal 100; if they are not the same, the terminal 100 discards the normal ACK frame or the normal receipt frame and continues to parse the subsequent user frames in the outbound physical frame.

[0345] The total data length of the Apack ACK frame is a fixed value, and the total data length of the Apack receipt frame is also a fixed value. For example, the total data length of the Apack ACK frame and the total data length of the Apack receipt frame can both be 40 bits.

[0346] (3) When the first user frame is a flexible feedback frame, the terminal 100 can further determine the subtype of the flexible feedback frame through the frame length field of the flexible feedback frame, and parse the user ID field or user CID field of the flexible feedback frame based on the frame format corresponding to the subtype of the flexible feedback frame. If the value of the user ID field (or the value of the user CID field) in the flexible feedback frame is the same as the user ID (or user CID) of the terminal 100, the terminal 100 can determine that the recipient of the flexible feedback frame is the terminal 100; if they are not the same, the terminal 100 discards the flexible feedback frame and continues to parse the subsequent user frames in the outbound physical frame. Among them, the subtypes of the flexible feedback frame include stop-wait Apack ACK frame, stop-wait Cpack ACK frame, parallel Apack ACK frame, parallel Cpack ACK frame, Apack receipt frame, and Cpack receipt frame.

[0347] For example, when the value of the frame length field in the flexible feedback frame is "100010", the subtype of the flexible feedback frame is a stop-and-wait Apack ACK frame. When the value of the frame length field in the flexible feedback frame is "000100", the subtype of the flexible feedback frame is a stop-and-wait Cpack ACK frame. When the value of the frame length field in the flexible feedback frame is "100110", the subtype of the flexible feedback frame is a parallel Apack ACK frame. When the value of the frame length field in the flexible feedback frame is "001100", the subtype of the flexible feedback frame is a parallel Cpack ACK frame. When the value of the frame length field in the flexible feedback frame is "101010", the subtype of the flexible feedback frame is an Apack receipt frame. When the value of the frame length field in the flexible feedback frame is "010000", the subtype of the flexible feedback frame is a Cpack receipt frame.

[0348] For the specific frame format of the flexible feedback frame, please refer to the above Figure 8D-Figure 8I The embodiments shown will not be described in detail here.

[0349] In one possible implementation, the version number field in the physical frame header of an outbound physical frame can be used to indicate the subtype of a flexible feedback frame included in the outbound physical frame. For example, when the value of the version number field is "000," only parallel Apack ACK frames are included in the outbound physical frame. When the value of the version number field is "001," only parallel Cpack ACK frames are included in the outbound physical frame, and so on.

[0350] 4. After determining the total data length of the first user frame, the terminal 100 may determine the position of the frame header of the second user frame in the outbound physical frame based on the total data length of the first user frame.

[0351] 5. After determining the frame type of the second user frame, the terminal 100 may parse the frame header of the second user frame based on the frame format corresponding to the frame type, and determine the total data length of the second user frame.

[0352] 6. After determining the data length of the entire second user frame, the terminal 100 may determine the position of the frame header of the third user frame in the outbound physical frame based on the total data length of the second user frame.

[0353] The parsing process of the terminal 100 for the second user frame and subsequent user frames in the outbound physical frame may refer to the parsing process for the first user frame in the outbound physical frame, which will not be repeated here.

[0354] In one possible implementation, after generating the initial user CID for the terminal 100, if the Beidou network device 200 determines that the initial user CID of the terminal 100 is the same as the starting identifier, the Beidou network device 200 may modify the user CID, where the modified user CID is different from the starting identifier. The user CID field of the waiting Cpack ACK frame, the user CID field of the parallel Cpack ACK frame, and the user CID field of the Cpack receipt frame carry the modified user CID.

[0355] For example, the initial user CID may be "01111110" and the starting identifier may be "01111110". If the initial user CID and the starting identifier overlap, the Beidou network device 200 may add "1" to the last bit of the initial user CID to obtain a corrected user CID. The corrected user CID may be "01111111".

[0356] The value of the initial user CID field may be the last 8 bits of the receiver ID of the Cpack ACK frame.

[0357] In one possible implementation, the Beidou network device 200 may determine an initial user CID value based on the user ID carried in the data request frame sent by the recipient of the Cpack format user frame (e.g., terminal 100) and the specified data information in the data request frame. For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the specified data information in the data request frame to obtain an 8-bit initial user CID.

[0358] For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the last 16 bits of data in the data portion of the data request frame to obtain an 8-bit initial user CID.

[0359] Among them, the process of terminal 100 calculating the initial user CID of terminal 100 and the process of terminal 100 correcting the initial user CID can refer to the process of Beidou network device 200 calculating the initial user CID of terminal 100 and the process of correcting the initial user CID, which will not be repeated here.

[0360] Another set of outbound user frames provided in an embodiment of the present application is introduced below.

[0361] Figure 10A An outbound Apack general data frame provided in an embodiment of the present application is shown.

[0362] like Figure 10A As shown, the outbound Apack general data frame may include an Apack general data frame header and user information. Among them, the user information is used to carry the outbound message data sent by the Beidou network device 200. The Apack general data frame header may include a frame type field, a frame length field, a user ID field, a total number of frames field, and a frame sequence number field. The frame type field is located at the beginning of the Apack general data frame header. Among them:

[0363] The frame type field can be used to indicate the frame type of the APPACK general data frame. The data length of the frame type field can be 2 bits, and the frame types of the outbound user frame can include APPACK general data frame, APPACK frame, APPACK receipt frame and compact frame.

[0364] The value and meaning of the frame type field may be as shown in Table 4 below:

[0365] Table 4

[0366] The value of the frame type field meaning 00 Apack Generic Data Frame 01 ApackACK frame 10 Apack receipt frame 11 Compact Frame

[0367] It can be seen from Table 4 above that the frame type indicated by the value of "00" in the frame type field is an Apack general data frame. The frame type indicated by the value of "01" in the frame type field is an Apack ACK frame. The frame type indicated by the value of "10" in the frame type field is an Apack receipt frame. The frame type indicated by the value of "11" in the frame type field is a compact frame. Among them, the compact frame may include a Cpack general data frame, a Cpack ACK frame and a Cpack receipt frame. Table 4 above is only used to explain this application and should not constitute a limitation. In a specific implementation, there may be more or fewer frame types, so the data length of the frame type field may be longer or shorter.

[0368] The frame length field can be used to indicate the data length of the user information in the APPACK general data frame. When the transmission rate of the outbound S2C-d channel branch is 2 kbit / s, the data length of the frame length field can be 8 bits; when the transmission rate of the outbound S2C-d channel branch is 4 kbit / s, the data length of the frame length field can be 9 bits.

[0369] The user ID field can be used to indicate the device identification of the receiving terminal of the APPACK universal data frame. The data length of the user ID field can be 34 bits.

[0370] The total number of frames field may be used to indicate the total number of APPACK general data frames in the SLC session in which the APPACK general data frame is located. When the maximum number of APPACK general data frames in the SLC session is 4, the data length of the total number of frames may be 2 bits.

[0371] The frame sequence number field can be used to indicate the frame sequence number of the APPACK general data frame in an SLC session. When the maximum number of APPACK general data frames in the SLC session is 4, the data length of the frame sequence number field can be 2 bits.

[0372] Figure 10B An outbound Apack ACK frame provided in an embodiment of the present application is shown.

[0373] like Figure 10B As shown, the Apack ACK frame may include an Apack ACK frame header and an ACK field. The ACK frame header may include a frame type field and a user ID field. The frame type field is located at the beginning of the Apack ACK frame header.

[0374] in:

[0375] The frame type field can be used to indicate the frame type of the APPACK frame. The data length of the frame type field can be 2 bits, and the frame type of the user frame can include APPACK general data frame, APPACK frame, APPACK receipt frame, and compact frame. The meaning of each value of the frame type field can be referred to as shown in Table 4 above and will not be repeated here.

[0376] The user ID field can be used to indicate the device identification of the receiving terminal of the ApackACK frame. The data length of the user ID field can be 34 bits.

[0377] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0378] Figure 10C An outbound Apack receipt frame provided in an embodiment of the present application is shown.

[0379] like Figure 10C As shown, the Apack receipt frame may include a receipt frame header and receipt information. The receipt frame header may include a frame type field and a user ID field. The frame type field is located at the beginning of the Apack receipt frame header.

[0380] The Frame Type field may be used to indicate the frame type of the APPACK Receipt frame. The data length of the Frame Type field may be 2 bits, and the frame types of outbound user frames may include APPACK General Data Frame, APPACK Frame, APPACK Receipt Frame, and Compact Frame. The meaning of each value in the Frame Type field may be as shown in Table 4 above and will not be further described here.

[0381] The user ID field can be used to indicate the device identification of the receiving terminal of the Apack receipt frame. The data length of the user ID field can be 34 bits.

[0382] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0383] Figure 10D-10F A set of outbound compact frames provided in an embodiment of the present application is shown.

[0384] Among them, subtypes of the compact frame may include Cpack general data frame, Cpack ACK frame and Cpack receipt frame.

[0385] Figure 10D Another outbound Cpack general data frame provided in an embodiment of the present application is shown.

[0386] like Figure 10DAs shown, the outbound Cpack universal data frame may include a Cpack universal data frame header and user information. The user information is used to carry the outbound message data sent by the Beidou network device 200. The Cpack universal data frame header may include a frame type field, a frame subtype field, a user CID field, and a frame length field. The frame type field is located at the beginning of the Cpack universal data frame header, and the frame subtype field is located before the frame length field.

[0387] The Frame Type field can be used to indicate the frame type of the Cpack general data frame. The data length of the Frame Type field can be 2 bits. The frame types of outbound user frames can include Apack general data frames, Apack ACK frames, Apack receipt frames, and compact frames. The meaning of each value in the Frame Type field can be referred to in Table 4 above and will not be repeated here.

[0388] The frame subtype field can be used to indicate the subtype of the Cpack general data frame. The data length of the frame subtype field can be 2 bits.

[0389] The value and meaning of the frame type field may be shown in Table 5 below:

[0390] Table 5

[0391] The value of the frame subtype field meaning 00 Cpack general data frame 01 CpackACK frame 10 Cpack receipt frame 11 RSV

[0392] As shown in Table 5 above, a value of "00" in the Frame Subtype field indicates a Cpack general data frame subtype. A value of "01" in the Frame Subtype field indicates a Cpack ACK frame subtype. A value of "10" in the Frame Subtype field indicates a Cpack receipt frame subtype. A value of "11" in the Frame Type field is reserved. In a specific implementation, more or fewer frame types may be present; therefore, the data length of the Frame Type field may be longer or shorter.

[0393] The User CID field can be used to indicate the compact device identifier of the receiving terminal of the Cpack universal data frame. The value of the User CID field is 8 bits. For the text description of the User CID, please refer to the above Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0394] The frame length field indicates the length of user information in the Cpack general data frame. When the outbound S2C-d channel transmission rate is 2 kbit / s, the frame length field can be 8 bits; when the outbound S2C-d channel transmission rate is 4 kbit / s, the frame length field can be 9 bits.

[0395] Figure 10E Another Cpack ACK frame is provided in an embodiment of the present application.

[0396] like Figure 10E As shown, the Cpack ACK frame may include a CpackACK frame header and an ACK field. The CpackACK frame header may include a frame type field, a frame subtype field, and a user CID field.

[0397] The Frame Type field can be used to indicate the frame type of the CpackACK. The data length of the Frame Type field can be 2 bits. The frame types of outbound user frames can include APPACK general data frames, APPACK frames, APPACK receipt frames, and compact frames. The meaning of each value in the Frame Type field can be referred to in Table 4 above and will not be repeated here.

[0398] The frame subtype field can be used to indicate the subtype of the CpackACK frame. The data length of the frame subtype field can be 2 bits. The meaning of each value of the frame subtype field can be referred to as shown in Table 5 above and will not be repeated here.

[0399] The User CID field can be used to indicate the compact device identifier of the receiver of the CpackACK frame. The data length of the User CID field can be 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0400] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0401] Figure 10F Another Cpack receipt frame is provided in an embodiment of the present application.

[0402] like Figure 10F As shown, the Cpack receipt frame includes a Cpack receipt frame header and receipt information. The Cpack receipt frame header may include a frame type field, a frame subtype field, and a user CID field.

[0403] The Frame Type field can be used to indicate the frame type of the Cpack Receipt frame. The data length of the Frame Type field can be 2 bits. The frame types of outbound user frames can include APPACK general data frames, APPACK ACK frames, APPACK Receipt frames, and compact frames. The meaning of each value in the Frame Type field can be referred to in Table 4 above and will not be repeated here.

[0404] The frame subtype field can be used to indicate the subtype of the Cpack receipt frame. The data length of the frame subtype field can be 2 bits. The meaning of each value of the frame subtype field can be referred to in Table 5 above and will not be repeated here.

[0405] The User CID field can be used to indicate the compact device identifier of the recipient of the Cpack receipt frame. The data length of the User CID field can be 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0406] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0407] In some embodiments, the above-mentioned Apack general data frame header may also include an AMenable field, wherein the AM enable field in the Apack general data frame header can be used to indicate whether the terminal 100 adopts confirmation mode or non-confirmation mode at the SLC layer to receive the Apack general data frame sent by the Beidou network device 200.

[0408] Optionally, the Cpack general data frame header may further include an AM enable field, which may be used to indicate whether the terminal 100 adopts confirmation mode or non-confirmation mode at the SLC layer to receive the Cpack general data frame sent by the Beidou network device 200.

[0409] In some embodiments, the Cpack general data frame header may further include a total number of frames field and a frame sequence number field. The total number of frames field in the Cpack general data frame header may be used to indicate the total number of Cpack general data frames included in the SLC session to which the Cpack general data frame belongs. When the maximum number of Cpack general data frames included in the SLC session is 4, the total number of frames field in the Cpack general data frame header may be 2 bits long.

[0410] The frame sequence number field in the Cpack general data frame header can be used to indicate the frame sequence number of the Cpack general data frame in an SLC session. Specifically, when the maximum number of Cpack general data frames in the SLC session is 4, the data length of the frame sequence number field in the Cpack general data frame header can be 2 bits.

[0411] Based on the above Figures 10A-10F A group of outbound user frames is shown, introducing the process of the Beidou network device 200 scheduling user frames in the outbound physical frames and the process of the terminal 100 parsing user frames from the outbound physical frames in an embodiment of the present application.

[0412] Figure 11 The user frame scheduling process provided in an embodiment of the present application is shown.

[0413] like Figure 11 As shown, the Beidou network device 200 can send an outbound physical frame on the S2C-d channel branch. The outbound physical frame may have a duration of 114ms and a transmission rate of 2kbit / s or 4kbit / s on the S2C-d channel branch.

[0414] The outbound physical frame may include a physical frame header, one or more user frames, and a check bit. The physical frame header may include a version number. The version number may be used to indicate the version of the physical frame format currently used by the Beidou network device 200.

[0415] Among them, the frame type of the user frame scheduled in the outbound physical frame may include Apack general data frame, Apack ACK frame, Apack receipt frame and compact frame. Among them, the subtype of the compact frame may include Cpack general data frame, Cpack ACK frame and Cpack receipt frame. Among them, the frame format of Apack general data frame, Apack ACK frame, Apack receipt frame and compact frame can refer to the above Figures 10B-10F The embodiments shown will not be described in detail here.

[0416] For example, the outbound physical frame may include a Cpack ACK frame sent to the terminal 100 , a Cpack general data frame sent to the terminal 400 , an Apack general data frame sent to the terminal 500 , and an Apack ACK frame sent to the terminal 600 .

[0417] The process of the terminal 100 parsing the outbound physical frame to obtain the user frame sent to the terminal 100 may be as follows:

[0418] 1. The terminal 100 may identify a physical frame header in an outbound physical frame at a PHY layer, wherein the physical frame header may include a version number field, and the data length of the version number field is 3 bits.

[0419] 2. When terminal 100 decodes an outbound physical frame on the S2C-d channel branch at the PHY layer, it can sequentially decode the frame using transmission rates of 2 kbit / s and 4 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 2 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 2 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 4 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 4 kbit / s. Therefore, after terminal 100 successfully decodes the outbound physical frame at the PHY layer, it can present the transmission rate on the S2C-d channel branch from the PHY layer to the SLC layer for use in determining the data length of the frame length field in the universal data frame when the SLC layer parses the user frame in the outbound physical frame. When the transmission rate on the S2C-d channel branch is 2 kbit / s, the data length of the frame length field in the universal data frame is 8 bits. When the transmission rate on the S2C-d channel branch is 4 kbit / s, the data length of the frame length field in the general data frame is 9 bits.

[0420] In the embodiment of the present application, the process of parsing the user frame from the outbound physical frame by the terminal 100 is described by taking the transmission rate on the S2C-d channel branch as 2 kbit / s and the data length of the frame length field in the general data frame as 8 bits as an example.

[0421] 3. Since the first field in the APPACK general data frame header, the first field in the APPACK ACK frame header, the first field in the APPACK receipt frame, and the first field in the compact frame are all 2-bit frame type fields, terminal 100 can determine the frame type of the first user frame based on the frame type field of the first user frame immediately following the physical frame header in the outbound physical frame.

[0422] (1) When the first user frame is an Apack general data frame, the terminal 100 can determine whether the user ID field of the first user frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the first user frame is an Apack general data frame sent to the terminal 100. The terminal 100 can frame the first user frame at the SLC layer and package it at the MDCP layer, and finally present the packaged MDCP SDU as an application layer message from the MDCP layer to the application layer. If the user ID field of the first user frame is not the same as the user ID of the terminal 100, the terminal 100 discards the Apack general data frame and continues to parse subsequent user frames in the outbound physical frame.

[0423] The data length of the Apack universal data frame header may be a fixed value, for example, 48 bits. The value of the frame length field in the Apack universal data frame header is used to indicate the data length of the user information in the universal data frame, for example, X bits. Therefore, the terminal 100 can determine that the total data length of the Apack universal data frame is (48+X) bits.

[0424] (2) When the first user frame is an ApackACK frame or an Apack receipt frame, the terminal 100 can determine whether the value of the user ID field of the ApackACK frame or the Apack receipt frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the ApackACK frame or the Apack receipt frame is the terminal 100; if they are not the same, the terminal 100 discards the ApackACK frame or the Apack receipt frame and continues to parse subsequent user frames in the outbound physical frame.

[0425] The total data length of the Apack ACK frame is a fixed value, and the total data length of the Apack receipt frame is also a fixed value. For example, the total data length of the Apack ACK frame and the total data length of the Apack receipt frame can both be 40 bits.

[0426] (3) When the first user frame is a compact frame, the terminal 100 can further determine the subtype of the compact frame through the frame subtype field of the compact frame, and parse the user CID field of the compact frame based on the frame format corresponding to the subtype of the compact frame. If the value of the user CID field in the compact frame is the same as the user CID of the terminal 100, the terminal 100 can determine that the recipient of the compact frame is the terminal 100; if they are not the same, the terminal 100 discards the compact frame and continues to parse the subsequent user frames in the outbound physical frame. Among them, the subtypes of the compact frame include Cpack general data frame, Cpack ACK frame and Cpack receipt frame.

[0427] For the specific frame format of compact frame, please refer to the above Figure 10D-10F The embodiments shown will not be described in detail here.

[0428] 4. After determining the total data length of the first user frame, the terminal 100 may determine the position of the frame header of the second user frame in the outbound physical frame based on the total data length of the first user frame.

[0429] 5. After determining the frame type of the second user frame, the terminal 100 may parse the frame header of the second user frame based on the frame format corresponding to the frame type, and determine the total data length of the second user frame.

[0430] 6. After determining the data length of the entire second user frame, the terminal 100 may determine the position of the frame header of the third user frame in the outbound physical frame based on the total data length of the second user frame.

[0431] The parsing process of the terminal 100 for the second user frame and subsequent user frames in the outbound physical frame may refer to the parsing process for the first user frame in the outbound physical frame, which will not be repeated here.

[0432] In one possible implementation, after generating an initial user CID for terminal 100, if Beidou network device 200 determines that the initial user CID of terminal 100 is the same as the starting identifier, Beidou network device 200 may modify the user CID, where the modified user CID is different from the starting identifier. The user CID field of the compact frame carries the modified user CID.

[0433] For example, the initial user CID may be "01111110" and the starting identifier may be "01111110". If the initial user CID and the starting identifier overlap, the Beidou network device 200 may add "1" to the last bit of the initial user CID to obtain a corrected user CID. The corrected user CID may be "01111111".

[0434] The value of the initial user CID field may be the last 8 bits of the receiver ID of the Cpack ACK frame.

[0435] In one possible implementation, the Beidou network device 200 may determine an initial user CID value based on the user ID and the specified data information in the data request frame sent by the recipient of the compact frame (e.g., the terminal 100). For example, the Beidou network device 200 may perform a hash operation on the user ID and the specified data information in the data request frame to obtain an 8-bit initial user CID.

[0436] For example, the Beidou network device 200 may perform a hash operation on the user ID carried in the data request frame and the last 16 bits of data in the data portion of the data request frame to obtain an 8-bit initial user CID.

[0437] Among them, the process of terminal 100 calculating the initial user CID of terminal 100 and the process of terminal 100 correcting the initial user CID can refer to the process of Beidou network device 200 calculating the initial user CID of terminal 100 and the process of correcting the initial user CID, which will not be repeated here.

[0438] Another set of outbound user frames provided in an embodiment of the present application is introduced below.

[0439] Figure 12A An outbound Apack general data frame provided in an embodiment of the present application is shown.

[0440] like Figure 12A As shown, the outbound Apack general data frame may include an Apack general data frame header and user information. Among them, the user information is used to carry the outbound message data sent by the Beidou network device 200. The Apack general data frame header may include a frame type field, a frame length field, a user ID field, a total number of frames field, and a frame sequence number field. The frame type field is located at the beginning of the Apack general data frame header. Among them:

[0441] The frame type field can be used to indicate the frame type of the APPACK general data frame. The data length of the frame type field can be 3 bits, and the frame types of outbound user frames can include APPACK general data frame, Cpack general data frame, APPACK frame, Cpack ACK frame, APPACK receipt frame, and Cpack receipt frame.

[0442] The value and meaning of the frame type field may be as shown in Table 6 below:

[0443] Table 6

[0444] The value of the frame type field meaning 000 Apack Generic Data Frame 001 Cpack general data frame 010 ApackACK frame 011 Cpack ACK frame 100 Apack receipt frame 101 Cpack receipt frame 110 RSV 111 RSV

[0445] It can be seen from Table 6 above that the frame type indicated by the value of "000" in the frame type field is an Apack general data frame. The frame type indicated by the value of "001" in the frame type field is a Cpack general data frame. The frame type indicated by the value of "010" in the frame type field is an ApackACK frame. The frame type indicated by the value of "011" in the frame type field is a CpackACK frame. The frame type indicated by the value of "100" in the frame type field is an Apack receipt frame. The frame type indicated by the value of "101" in the frame type field is a Cpack receipt frame. The values of "110" and "111" in the frame type field are reserved values. Table 6 above is only used to explain this application and should not constitute a limitation. In a specific implementation, there may be more or fewer frame types, and therefore, the data length of the frame type field may be longer or shorter.

[0446] The frame length field indicates the length of user information in a general data frame. When the outbound S2C-d channel transmission rate is 2 kbit / s, the frame length field can be 8 bits; when the outbound S2C-d channel transmission rate is 4 kbit / s, the frame length field can be 9 bits.

[0447] The user ID field can be used to indicate the device identification of the receiving terminal of the universal data frame. The data length of the user ID field can be 34 bits.

[0448] The total number of frames field may be used to indicate the total number of general data frames in the SLC session in which the general data frame resides. When the maximum number of general data frames in the SLC session is 4, the total number of frames may have a data length of 2 bits.

[0449] The frame sequence number field may be used to indicate the frame sequence number of the general data frame in an SLC session. When the maximum number of general data frames in an SLC session is 4, the data length of the frame sequence number field may be 2 bits.

[0450] Figure 12B An outbound Apack ACK frame provided in an embodiment of the present application is shown.

[0451] like Figure 12B As shown, the Apack ACK frame may include an Apack ACK frame header and an ACK field. The ACK frame header may include a frame type field and a user ID field. The frame type field is located at the beginning of the Apack ACK frame header.

[0452] in:

[0453] The Frame Type field indicates the frame type of the ACK frame. The data length of the Frame Type field can be 3 bits. User frame types can include Apack general data frame, Cpack general data frame, ApackACK frame, CpackACK frame, Apack receipt frame, and Cpack receipt frame. The meaning of each value in the Frame Type field can be found in Table 6 above and will not be further described here.

[0454] The user ID field can be used to indicate the device identification of the receiving terminal of the ACK frame. The data length of the user ID field can be 34 bits.

[0455] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0456] Figure 12C An outbound Apack receipt frame provided in an embodiment of the present application is shown.

[0457] like Figure 12C As shown, the Apack receipt frame may include a receipt frame header and receipt information. The Apack receipt frame header may include a frame type field and a user ID field. The frame type field is located at the beginning of the Apack receipt frame header.

[0458] The Frame Type field indicates the frame type of the APPACK Receipt frame. The data length of the Frame Type field can be 3 bits. Outbound user frame types can include APPACK General Data Frame, CPACK General Data Frame, APPACK Frame, CPACK Frame, APPACK Receipt Frame, and CPACK Receipt Frame. The meaning of each value in the Frame Type field can be found in Table 6 above and will not be further described here.

[0459] The user ID field can be used to indicate the device identification of the receiving terminal of the Apack receipt frame. The data length of the user ID field can be 34 bits.

[0460] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0461] Figure 12D Another outbound Cpack general data frame provided in an embodiment of the present application is shown.

[0462] like Figure 12D As shown, the outbound Cpack universal data frame may include a Cpack universal data frame header and user information. The user information is used to carry the outbound message data sent by the Beidou network device 200. The Cpack universal data frame header may include a frame type field, a user CID field, and a frame length field. The frame type field is located at the beginning of the Cpack universal data frame header.

[0463] The Frame Type field can be used to indicate the frame type of the Cpack general data frame. The data length of the Frame Type field can be 3 bits. Outbound user frame types can include Apack general data frame, Cpack general data frame, Apack ACK frame, Cpack ACK frame, Apack receipt frame, and Cpack receipt frame. The meaning of each value in the Frame Type field can be found in Table 6 above and will not be further described here.

[0464] The User CID field can be used to indicate the compact device identifier of the receiving terminal of the Cpack universal data frame. The value of the User CID field is 8 bits. For the text description of the User CID, please refer to the above Figure 6DThe text description of the user CID in the illustrated embodiment is not repeated here.

[0465] The frame length field indicates the length of user information in the Cpack general data frame. When the outbound S2C-d channel transmission rate is 2 kbit / s, the frame length field can be 8 bits; when the outbound S2C-d channel transmission rate is 4 kbit / s, the frame length field can be 9 bits.

[0466] Figure 12E Another Cpack ACK frame is provided in an embodiment of the present application.

[0467] like Figure 12E As shown, the Cpack ACK frame may include a CpackACK frame header and an ACK field. The CpackACK frame header may include a frame type field and a user CID field.

[0468] The Frame Type field can be used to indicate the frame type of the CpackACK. The data length of the Frame Type field can be 3 bits. Outbound user frame types can include Apack General Data Frame, Cpack General Data Frame, ApackACK Frame, Cpack ACK Frame, Apack Receipt Frame, and Cpack Receipt Frame. The meaning of each value in the Frame Type field can be found in Table 6 above and will not be further described here.

[0469] The User CID field can be used to indicate the compact device identifier of the receiver of the CpackACK frame. The data length of the User CID field can be 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0470] The ACK field can be used to indicate the Beidou network device 200's reception status of N general data frames sent consecutively by the terminal in an SLC session. The maximum value of N can be 4. The ACK field includes an acknowledgment identifier bitmap (ACK bitmap), which can have a data length of 4 bits. One bit in the ACK bitmap indicates the reception status of one general data frame among the N general data frames.

[0471] Figure 12F Another Cpack receipt frame is provided in an embodiment of the present application.

[0472] like Figure 12FAs shown, the Cpack receipt frame includes a Cpack receipt frame header and receipt information. The Cpack receipt frame header may include a frame type field and a user CID field.

[0473] The Frame Type field can be used to indicate the frame type of the Cpack Receipt Frame. The Frame Type field can have a data length of 3 bits. Outbound user frame types can include Apack General Data Frame, Cpack General Data Frame, Apack ACK Frame, Cpack ACK Frame, Apack Receipt Frame, and Cpack Receipt Frame. The meaning of each value in the Frame Type field can be found in Table 6 above and will not be further described here.

[0474] The User CID field can be used to indicate the compact device identifier of the recipient of the Cpack receipt frame. The data length of the User CID field can be 8 bits. For the text description of the User CID, please refer to the aforementioned Figure 6D The text description of the user CID in the illustrated embodiment is not repeated here.

[0475] The receipt information can be used to indicate the parsing status of the application layer message sent by the terminal by the Beidou network device 200. The data length of the receipt information can be 4 bits.

[0476] Based on the above Figures 12A-12F A group of outbound user frames is shown, and a process of scheduling user frames in outbound physical frames by the Beidou network device 200 in an embodiment of the present application is specifically introduced.

[0477] Figure 13 The scheduling process of the user frame provided in the embodiment of the present application is shown.

[0478] like Figure 13 As shown, the Beidou network device 200 can send an outbound physical frame on the S2C-d channel branch. The outbound physical frame may have a duration of 114ms and a transmission rate of 2kbit / s or 4kbit / s on the S2C-d channel branch.

[0479] The outbound physical frame may include a physical frame header, one or more user frames, and a check bit. The physical frame header may include a version number. The version number may be used to indicate the version of the physical frame format currently used by the Beidou network device 200.

[0480] Among them, the frame type of the user frame scheduled in the outbound physical frame may include Apack general data frame, Apack ACK frame, Apack receipt frame and compact frame. Among them, the subtype of the compact frame may include Cpack general data frame, Cpack ACK frame and Cpack receipt frame. Among them, the frame format of Apack general data frame, Apack ACK frame, Apack receipt frame and compact frame can refer to the above Figures 10B-10F The embodiments shown will not be described in detail here.

[0481] For example, the outbound physical frame may include a Cpack ACK frame sent to the terminal 100 , a Cpack general data frame sent to the terminal 400 , an Apack general data frame sent to the terminal 500 , and an Apack ACK frame sent to the terminal 600 .

[0482] The process of the terminal 100 parsing the outbound physical frame to obtain the user frame sent to the terminal 100 may be as follows:

[0483] 1. The terminal 100 may identify a physical frame header in an outbound physical frame at a PHY layer, wherein the physical frame header may include a version number field, and the data length of the version number field is 3 bits.

[0484] 2. When terminal 100 decodes an outbound physical frame on the S2C-d channel branch at the PHY layer, it can sequentially decode the frame using transmission rates of 2 kbit / s and 4 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 2 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 2 kbit / s. When terminal 100 successfully decodes the outbound physical frame at the 4 kbit / s transmission rate, terminal 100 can determine that the transmission rate on the S2C-d channel branch is 4 kbit / s. Therefore, after terminal 100 successfully decodes the outbound physical frame at the PHY layer, it can present the transmission rate on the S2C-d channel branch from the PHY layer to the SLC layer for use in determining the data length of the frame length field in the universal data frame when the SLC layer parses the user frame in the outbound physical frame. When the transmission rate on the S2C-d channel branch is 2 kbit / s, the data length of the frame length field in the universal data frame is 8 bits. When the transmission rate on the S2C-d channel branch is 4 kbit / s, the data length of the frame length field in the general data frame is 9 bits.

[0485] 3. Since the first field in the Apack general data frame header, the first field in the Apack ACK frame header, the first field in the Apack receipt frame, the first field in the Cpack general data frame header, the first field in the Cpack ACK frame header, and the first field in the Cpack receipt frame are all 3-bit frame type fields, terminal 100 can determine the frame type of the first user frame based on the frame type field of the first user frame immediately following the physical frame header in the outbound physical frame.

[0486] (1) When the first user frame is an Apack general data frame, the terminal 100 can determine whether the user ID field of the Apack general data frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the Apack general data frame is the terminal 100. The terminal 100 can frame the Apack general data frame as an SLC PDU at the SLC layer and package it at the MDCP layer, and finally present the packaged MDCP SDU as an application layer message from the MDCP layer to the application layer. If the user ID field of the Apack general data frame is not the same as the user ID of the terminal 100, the terminal 100 discards the Apack general data frame and continues to parse the subsequent user frames in the outbound physical frame.

[0487] The data length of the Apack general data frame header can be a fixed value, for example, 49 bits. The value of the frame length field in the Apack general data frame header is used to indicate the data length of the user information in the Apack general data frame, for example, X bits. Therefore, the terminal 100 can determine that the total data length of the Apack general data frame is (49+X) bits.

[0488] (2) When the first user frame is an ApackACK frame or an Apack receipt frame, the terminal 100 can determine whether the value of the user ID field of the ApackACK frame or the Apack receipt frame is the same as the user ID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the ApackACK frame or the Apack receipt frame is the terminal 100; if they are not the same, the terminal 100 discards the ApackACK frame or the Apack receipt frame and continues to parse subsequent user frames in the outbound physical frame.

[0489] The total data length of the Apack ACK frame is a fixed value, and the total data length of the Apack receipt frame is also a fixed value. For example, the total data length of the Apack ACK frame and the total data length of the Apack receipt frame can both be 41 bits.

[0490] (3) When the first user frame is a Cpack general data frame, terminal 100 can determine whether the user CID field of the Cpack general data frame is the same as the user CID of terminal 100. If they are the same, terminal 100 can determine that the recipient of the Cpack general data frame is terminal 100. Terminal 100 can frame the Cpack general data frame as an SLC PDU at the SLC layer and package it at the MDCP layer, and finally present the packaged MDCP SDU as an application layer message from the MDCP layer to the application layer. If the user CID field of the Cpack general data frame is not the same as the user CID of terminal 100, terminal 100 discards the Cpack general data frame and continues to parse subsequent user frames in the outbound physical frame.

[0491] The data length of the Cpack general data frame header can be a fixed value, for example, 19 bits. The value of the frame length field in the Cpack general data frame header is used to indicate the data length of the user information in the Cpack general data frame, for example, X bits. Therefore, terminal 100 can determine that the total data length of the Cpack general data frame is (19 + X) bits.

[0492] (4) When the first user frame is a CpackACK frame or a Cpack receipt frame, the terminal 100 can determine whether the value of the user CID field of the CpackACK frame or the Cpack receipt frame is the same as the user CID of the terminal 100. If they are the same, the terminal 100 can determine that the recipient of the CpackACK frame or the Cpack receipt frame is the terminal 100; if they are not the same, the terminal 100 discards the CpackACK frame or the Cpack receipt frame and continues to parse the subsequent user frames in the outbound physical frame.

[0493] The total data length of the Cpack ACK frame is a fixed value, and the total data length of the Cpack receipt frame is also a fixed value. For example, the total data length of the Cpack ACK frame and the total data length of the Cpack receipt frame can both be 15 bits.

[0494] 4. After determining the total data length of the first user frame, the terminal 100 may determine the position of the frame header of the second user frame in the outbound physical frame based on the total data length of the first user frame.

[0495] 5. After determining the frame type of the second user frame, the terminal 100 may parse the frame header of the second user frame based on the frame format corresponding to the frame type, and determine the total data length of the second user frame.

[0496] 6. After determining the data length of the entire second user frame, the terminal 100 may determine the position of the frame header of the third user frame in the outbound physical frame based on the total data length of the second user frame.

[0497] The parsing process of the terminal 100 for the second user frame and subsequent user frames in the outbound physical frame may refer to the parsing process for the first user frame in the outbound physical frame, which will not be repeated here.

[0498] The following describes a compact feedback method in a Beidou communication system provided in an embodiment of the present application.

[0499] Figure 14 A flow chart of a compact feedback method in a Beidou communication system provided in an embodiment of the present application is shown.

[0500] like Figure 14 As shown, the compact feedback method in the Beidou communication system may include the following steps:

[0501] S1401. The terminal 100 may split a first application layer message into one or more SLC SDUs, where the one or more SLC SDUs include a first SLC SDU.

[0502] Specifically, for the process of the terminal 100 splitting the first application layer message into one or more SLC SDUs, reference can be made to the aforementioned Figure 4A The embodiments shown will not be described in detail here.

[0503] S1402. Terminal 100 splits the first SLC SDU into N SLC PDUs.

[0504] Specifically, for the process of the terminal 100 splitting the first SLC SDU into N SLC PDUs, please refer to the aforementioned Figure 4A The embodiments shown will not be described in detail here.

[0505] S1403: The terminal 100 sends the N SLC PDUs in the first SLC SDU to the Beidou network device 200. The frame headers of the N SLC PDUs carry the user ID of the terminal 100 and an AM enable field, where the AMenable field is used to indicate the confirmation mode supported by the terminal 100.

[0506] The frame format of the first SLC SDU can be referred to Figure 15 The frame format of the SLC PDU is shown.

[0507] like Figure 15As shown, an inbound physical frame may include a synchronization header and a data segment. The synchronization header may be used to synchronize the inbound physical frame with the Beidou network device 200 and identify the start position of the data segment. The synchronization header may be 40ms long.

[0508] The data segment of the inbound physical frame may include a user frame and a check bit. In the Beidou communication system 10, a cyclic redundancy check (CRC) may be used to check the data segment, and the check bit may include a CRC check code. The inbound user frame may include frame header information (also referred to as frame format indication information) and user information. In the general data frame, the frame header information of the inbound user frame may include a version number, a subtype indication field, a user ID field, an outbound link indication field, an acknowledgment mode enable (AM enable) field, a total number of frames field, a frame sequence number field, a service data unit alternation indication field, and a reserved (RSV) field. The frame type of the SLC PDU is a general data frame.

[0509] The version number field can be used to indicate the protocol format version of the inbound user frame. The data length of the version number field can be 3 bits.

[0510] The subtype indication field can be used to indicate the subtype of the inbound user frame. The data length of the subtype indication field can be 3 bits. Subtypes of inbound user frames can include general data frames (or information message frames), ACK frames, receipt frames, location reporting frames, emergency rescue frames, and so on.

[0511] The user ID field may be used to indicate the device identification of the terminal 100. The data length of the user ID field may be 34 bits.

[0512] The AM enable field may be used to indicate the confirmation mode supported by the terminal 100 at the SLC layer. The data length of the AM enable field may be 2 bits.

[0513] The value and meaning of the AM enable field may be as shown in Table 7 below:

[0514] Table 7

[0515] The value of the AM enable field meaning 00 Unconfirmed mode 01 Cpack confirmation mode 10 Apack confirmation mode 11 Retention (RSV)

[0516] As can be seen from Table 7 above, the value of the AM enable field is "00", indicating that terminal 100 does not support the feedback mechanism in acknowledgement mode, that is, data is transmitted in non-acknowledgement mode. When Beidou network device 200 receives an SLC PDU sent by terminal 100 with the value of the AM enable field in the field "00", Beidou network device 200 may not send an ACK frame to terminal 100. Table 7 above is provided for illustrative purposes only and should not be construed as limiting the present application.

[0517] The value of the AM enable field is "01", indicating that the terminal 100 supports the feedback mechanism of the Cpack confirmation mode. When the Beidou network device 200 receives the value of the AM enable field in the SLC PDU sent by the terminal 100 and the value is "01", the Beidou network device 200 can send a feedback frame in the Cpack format (including a Cpack ACK frame or a Cpack receipt frame) to the terminal 100.

[0518] The value of the AM enable field is "10", indicating that the terminal 100 supports the feedback mechanism of the Apack confirmation mode. When the Beidou network device 200 receives the value of the AM enable field in the SLC PDU sent by the terminal 100 and the value is "10", the Beidou network device 200 can send a feedback frame in the Apack format (including an Apack ACK frame or an Apack receipt frame) to the terminal 100.

[0519] The Total Frames field may be used to indicate the total number of general data frames in the SLC session in which the general data frame (i.e., SLC PDU) resides. The Total Frames field may be 2 bits long. When the Total Frames field is 2 bits long, a maximum of four general data frames may be included in an SLC session.

[0520] The frame sequence number field can be used to indicate the sequence number of the general data frame in an SLC session. The length of the frame sequence number field can be 2 bits.

[0521] The SAI field indicates whether the general data frame is new. By comparing the SAI value with the previous general data frame in the SLC session, a flip indicates that the general data frame is new; otherwise, it is a retransmitted frame. The SAI field can be 1 bit long.

[0522] The reserved (RSV) field can be used to reserve for protocol extension. The data length of the reserved field can be 3 bits.

[0523] The user information may include part or all of the data of the application layer message.

[0524] S1404: The Beidou network device 200 receives M SLC PDUs in the first SLC SDU, where M is less than or equal to N, and M and N are positive integers.

[0525] S1405: After receiving the M SLC PDUs in the first SLC SDU, the Beidou network device 200 determines based on the AM enable fields of the M SLC PDUs that the terminal 100 supports the Cpack confirmation mode and generates a first Cpack feedback frame, wherein the first Cpack feedback frame carries the user CID of the terminal 100.

[0526] When the first Cpack feedback frame is a Cpack ACK frame, the first Cpack feedback frame is used to indicate the Beidou network device's reception of the N SLC PDUs in the first SLC SDU. When the first Cpack feedback frame is a Cpack receipt frame, the first Cpack receipt frame is used to indicate the Beidou network device 200's parsing of the first application layer message.

[0527] S1406. The Beidou network device 200 schedules the first Cpack feedback frame into the first outbound physical frame.

[0528] S1407. The Beidou network device 200 sends a first outbound physical frame.

[0529] S1408. The Beidou network device 200 parses the first outbound physical frame to obtain a first Cpack feedback frame.

[0530] The frame format of the first Cpack feedback frame can be as described above. Figure 6D The process of the BeiDou network device 200 scheduling the first Cpack feedback frame to the first outbound physical frame and the process of the terminal 100 parsing the first Cpack feedback frame from the first outbound physical frame can refer to the above Figure 7 The embodiments shown will not be described in detail here.

[0531] In a possible implementation, the frame format of the first Cpack feedback frame may be as described above. Figure 8E 、 Figure 8G 、 Figure 8I The process of the BeiDou network device 200 scheduling the first Cpack feedback frame to the first outbound physical frame and the process of the terminal 100 parsing the first Cpack feedback frame from the first outbound physical frame can refer to the above Figure 9 The embodiments shown will not be described in detail here.

[0532] In a possible implementation, the frame format of the first Cpack feedback frame may be as described above. Figure 10E 、 Figure 10FThe process of the BeiDou network device 200 scheduling the first Cpack feedback frame to the first outbound physical frame and the process of the terminal 100 parsing the first Cpack feedback frame from the first outbound physical frame can refer to the above Figure 11 The embodiments shown will not be described in detail here.

[0533] In a possible implementation, the frame format of the first Cpack feedback frame may be as described above. Figure 12E 、 Figure 12F The process of the BeiDou network device 200 scheduling the first Cpack feedback frame to the first outbound physical frame and the process of the terminal 100 parsing the first Cpack feedback frame from the first outbound physical frame can refer to the above Figure 13 The embodiments shown will not be described in detail here.

[0534] In one possible implementation, upon determining that the terminal 100 supports the Cpack confirmation mode, the Beidou network device 200 may construct feedback frames in both Cpack and Apack formats, namely, a first Cpack feedback frame and a first Apack feedback frame. The Beidou network device 200 may send the first Cpack feedback frame to the terminal 100 within a specified time window after receiving the M SLC PDUs in the first SLC SDU. The terminal 100 and the Beidou network device 200 may have preset values for the specified time window. For example, the specified time window may be from the second physical transmission time slot to the fourth physical transmission time slot after the Beidou network device 200 receives the M SLC PDUs in the first SLC SDU. A physical transmission time slot may be 125 ms.

[0535] If the Beidou network device 200 fails to schedule the first Cpack feedback frame within the specified time window, the Beidou network device 200 may adopt the Apack feedback mode and schedule the first Apack feedback frame into the outbound physical frame to feed back to the terminal 100 .

[0536] If the terminal 100 fails to parse the first Cpack feedback frame within the specified time window, the terminal 100 may attempt to parse the Apack feedback frame sent by the Beidou network device 200 to the terminal 100 from the outbound physical frame according to the frame format of the Apack feedback frame.

[0537] In one possible implementation, the Beidou network device 200 can schedule user frames of multiple terminals in an outbound physical frame. If the time window in which the Beidou network device 200 sends a Cpack feedback frame to the terminal 100 overlaps with the time window in which the Beidou network device 200 sends a Cpack user frame (including a Cpack general data frame and a Cpack feedback frame) to the terminal 400, and the user CID of the terminal 100 is the same as the user CID of the terminal 400, the Beidou network device 200 can use the Apack confirmation mode to send an Apack feedback frame to the terminal 100 and send an Apack user frame (including a Cpack general data frame and a Cpack feedback frame) to the terminal 400. In this way, it is possible to avoid the terminal 100's user CID from mistakenly receiving user frames of other terminals when the user CID of the terminal 100 overlaps with the user CID of other terminals.

[0538] Optionally, if the time window in which the Beidou network device 200 sends a Cpack feedback frame to the terminal 100 overlaps with the time window in which the Beidou network device 200 sends a Cpack user frame to the terminal 400, and the user CID of the terminal 100 is the same as the user CID of the terminal 400, and the downlink beam in which the terminal 100 receives the Cpack feedback frame overlaps with the downlink beam in which the terminal 400 receives the Cpack user frame, then the Beidou network device 200 may use the Apack confirmation mode to send an Apack feedback frame to the terminal 100 and send an Apack user frame (including a Cpack general data frame and a Cpack feedback frame) to the terminal 400. In this way, when the user CID of the terminal 100 overlaps with the user CID of other terminals, it is possible to avoid erroneous reception of user frames of other terminals.

[0539] According to a compact feedback method in a Beidou communication system provided by an embodiment of the present application, a terminal can send N SLC PDUs to a Beidou network device, where N is a positive integer, and the N SLC PDUs include a first SLC PDU, wherein the frame header information of the first SLC PDU includes a first user identification ID field and an acknowledgment mode enable AM enable field, the first user identification ID field is used to indicate the device identification of the terminal, and the AM enable field is used to indicate the acknowledgment mode supported by the terminal at the SLC layer. After the Beidou network device receives M SLC PDUs (N is greater than or equal to M, and M is a positive integer) among the N SLC PDUs sent by the terminal, if the value of the AM enable field is used to indicate that the terminal supports the Cpack acknowledgment mode, the Beidou network device can send a first Cpack feedback frame to the terminal, the first Cpack feedback frame is used to indicate the Beidou network device's reception status for the N SLC PDUs; wherein the first Cpack feedback frame includes a first user CID field, the first user CID field is used to indicate the compact device identification of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

[0540] The frame formats of Apack feedback frame and Cpack feedback frame can refer to the above Figures 6A-6D The embodiment shown, or referring to the above Figures 8A-8I The embodiment shown, or referring to the above Figures 10A-10F The embodiment shown, or referring to the above Figures 12A-12F The embodiments shown will not be described in detail here.

[0541] The above content elaborates on the method provided by the present application. In order to facilitate better implementation of the above scheme of the embodiment of the present application, the embodiment of the present application also provides corresponding devices or equipment.

[0542] In the embodiment of the present application, the terminal 100 can be divided into functional modules according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods.

[0543] The following will be combined Figures 16 to 19 The communication device according to the embodiment of the present application is described in detail.

[0544] In the case of integrated units, see Figure 16 , Figure 161 is a schematic diagram of the structure of the communication device 1600 provided in an embodiment of the present application. The communication device 1600 may be the terminal 100 in the above embodiment. Optionally, the communication device 1600 may be a chip / chip system, for example, a Beidou communication chip. Figure 16 As shown, the communication device 1600 may include a transceiver unit 1610 and a processing unit 1620 .

[0545] In one design, processing unit 1620 can be used to generate N SLC PDUs, wherein the N SLC PDUs include a first SLC PDU, and the frame header of the first SLC PDU includes a first user ID field and an AM enable field, the first user ID field is used to indicate the device identification of the terminal, and the AM enable field is used to indicate the confirmation mode supported by the terminal at the SLC layer.

[0546] The transceiver unit 1610 may be configured to send the N SLC PDUs to the Beidou network device.

[0547] The transceiver unit 1610 is also used to receive the first Cpack feedback frame sent by the Beidou network device when the value of the AM enable field is used to indicate that the terminal supports the Cpack confirmation mode. The first Cpack feedback frame is used to indicate the reception status of the Beidou network device for N SLC PDUs; wherein the first Cpack feedback frame includes a first user CID field, the first user CID field is used to indicate the compact device identifier of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

[0548] Optionally, the transceiver unit 1610 may also be used to perform the above Figure 14 The terminal 100 in the illustrated method embodiment performs the functional steps related to sending and receiving.

[0549] Optionally, the processing unit 1620 may also be configured to execute the above Figure 14 In the illustrated method embodiment, the terminal 100 performs functional steps such as generation of an SLC PDU and parsing of user frames in an outbound physical frame.

[0550] It should be understood that the communication device 1600 in this design can execute the method steps executed by the terminal 100 in the aforementioned embodiment. For the sake of brevity, they will not be repeated here.

[0551] In the case of integrated units, see Figure 17 , Figure 171 is a structural diagram of the communication device 1700 provided in an embodiment of the present application. The communication device 1700 may be the Beidou network device 200 in the above embodiment. Optionally, the communication device 1700 may be a specific network element in the Beidou network device 200, for example, a network element or a combination of multiple network elements in the Beidou ground transceiver station 22, the Beidou central station 23, and the Beidou short message fusion communication platform 24. Figure 17 As shown, the communication device 1700 may include a transceiver unit 1710 and a processing unit 1720 .

[0552] In one design, the transceiver unit 1710 may be configured to receive M SLC PDUs sent by a terminal, where M is a positive integer, and the M SLC PDUs include a first SLC PDU, wherein a frame header of the first SLC PDU includes a first user ID field and an AM enable field, where the first user ID field is used to indicate a device identifier of the terminal, and the AM enable field is used to indicate an acknowledgement mode supported by the terminal at the SLC layer.

[0553] The processing unit 1720 may be configured to generate a first Cpack feedback frame based on the received M SLC PDUs.

[0554] The transceiver unit 1710 is also used to send a first Cpack feedback frame to the terminal when the value of the AM enable field is used to indicate that the terminal supports the Cpack confirmation mode. The first Cpack feedback frame is used to indicate the reception status of the Beidou network device for M SLC PDUs; wherein the first Cpack feedback frame includes a first user CID field, the first user CID field is used to indicate the compact device identifier of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

[0555] Optionally, the transceiver unit 1710 may also be used to perform the above Figure 14 The Beidou network device 200 in the illustrated method embodiment performs the functional steps related to sending and receiving.

[0556] Optionally, the processing unit 1720 may also be configured to execute the above Figure 14 In the illustrated method embodiment, the Beidou network device 200 performs functional steps such as parsing the SLC PDU sent by the terminal 100 and generating various outbound user frames.

[0557] It should be understood that the communication device 1700 in this design can execute the method steps executed by the Beidou network device 200 in the aforementioned embodiment. For the sake of brevity, they will not be repeated here.

[0558] The above describes the terminal 100 and BeiDou network device 200 of the embodiment of the present application. It should be understood that any device having the above Figure 16 Any product having the functions of the terminal 100 as described above Figure 17 Any product that implements the functions of the Beidou network device 200 falls within the protection scope of the embodiments of the present application.

[0559] As a possible product form, the terminal 100 described in the embodiment of the present application can be implemented by a general bus architecture.

[0560] See also Figure 18 , Figure 18 1 is a schematic diagram of the structure of the communication device 1800 provided in an embodiment of the present application. The communication device 1800 may be the terminal 100, or a device therein. Figure 18 As shown, the communication device 1800 includes a processor 1801 and a transceiver 1802 connected to the internal communication of the processor. The processor 1801 can be a general-purpose processor or a dedicated processor. For example, it can be a baseband processor or a central processing unit for satellite communication. The baseband processor for satellite communication can be used to process satellite communication protocols and satellite communication data, and the central processing unit can be used to control the communication device (such as a baseband chip, a terminal, a terminal chip, etc.), execute computer programs, and process computer program data. The transceiver 1802 can be called a transceiver unit, a transceiver, or a transceiver circuit, etc., and is used to implement transceiver functions. The transceiver 1802 can include a receiver and a transmitter. The receiver can be called a receiver or a receiving circuit, etc., and is used to implement the receiving function; the transmitter can be called a transmitter or a transmitting circuit, etc., and is used to implement the transmitting function. Optionally, the communication device 1800 can also include an antenna 1803 and / or a radio frequency unit (not shown in the figure). The antenna 1803 and / or the radio frequency unit may be located inside the communication device 1800 or may be separated from the communication device 1800 , that is, the antenna 1803 and / or the radio frequency unit may be remotely or distributedly deployed.

[0561] Optionally, the communication device 1800 may include one or more memories 1804, which may store instructions, such as computer programs. The computer programs may be executed on the communication device 1800 to enable the communication device 1800 to perform the methods described in the above method embodiments. Optionally, the memories 1804 may also store data. The communication device 1800 and the memories 1804 may be provided separately or integrated together.

[0562] The processor 1801 , the transceiver 1802 , and the memory 1804 may be connected via a communication bus.

[0563] In one design, the communication device 1800 may be configured to perform the functions of the terminal 100 in the aforementioned embodiment: the processor 1801 may be configured to perform the aforementioned Figure 14 The terminal 100 performs the following steps in the method embodiment shown in FIG. 1 : generating the SLC PDU, parsing the user frame in the outbound physical frame, and / or other processes for the technology described herein; the transceiver 1802 can be used to perform the above Figure 14 The terminal 100 in the illustrated method embodiment performs functional steps related to transmission and reception and / or other processes for the technology described herein.

[0564] In any of the above designs, processor 1801 may include a transceiver for implementing receiving and transmitting functions. For example, the transceiver may be a transceiver circuit, an interface, or an interface circuit. The transceiver circuit, interface, or interface circuit for implementing the receiving and transmitting functions may be separate or integrated. The transceiver circuit, interface, or interface circuit may be used for reading and writing code / data, or the transceiver circuit, interface, or interface circuit may be used for transmitting or delivering signals.

[0565] In any of the above designs, processor 1801 may store instructions, which may be computer programs. The computer programs, when executed on processor 1801, may cause communication device 1800 to execute the method steps performed by terminal 100 in the above method embodiments. The computer programs may be fixed in processor 1801, in which case processor 1801 may be implemented by hardware.

[0566] In one implementation, the communication device 1800 may include a circuit that can implement the functions of sending, receiving, or communicating in the aforementioned method embodiments. The processor and transceiver described in this application can be implemented on an integrated circuit (IC), an analog IC, a radio frequency integrated circuit RFIC, a mixed signal IC, an application specific integrated circuit (ASIC), a printed circuit board (PCB), an electronic device, etc. The processor and transceiver can also be manufactured using various IC process technologies, such as complementary metal oxide semiconductor (CMOS), N-type metal oxide semiconductor (nMetal-oxide-semiconductor, NMOS), P-type metal oxide semiconductor (positive channel metal oxide semiconductor, PMOS), bipolar junction transistor (bipolar junction transistor, BJT), bipolar CMOS (BiCMOS), silicon germanium (SiGe), gallium arsenide (GaAs), etc.

[0567] The scope of the communication device described in this application is not limited thereto, and the structure of the communication device may not be limited thereto. Figure 18 The communication device 1800 may be a standalone device or may be part of a larger device. For example, the communication device 1800 may be:

[0568] (1) An independent integrated circuit (IC), or chip, or chip system or subsystem;

[0569] (2) a collection of one or more ICs, optionally including a storage component for storing data and computer programs;

[0570] (3) ASIC, such as modem;

[0571] (4) Modules that can be embedded in other devices;

[0572] (5) Receivers, terminals, smart terminals, cellular phones, wireless devices, handheld devices, mobile units, vehicle-mounted devices, network devices, cloud devices, artificial intelligence devices, etc.;

[0573] (6)Others, etc.

[0574] As a possible product form, any network element in the Beidou network device 200 described in the embodiment of the present application (for example, the Beidou ground transceiver station 22, the Beidou central station 23, the Beidou short message fusion communication platform 24) can be implemented by a general bus architecture.

[0575] See also Figure 19 , Figure 19 1 is a schematic diagram of the structure of the communication device 1900 provided in the embodiment of the present application. The communication device 1900 may be the Beidou network device 200, or a device therein. Figure 19As shown, the communication device 1900 includes a processor 1901 and a transceiver 1902 connected to the internal communication of the processor. The processor 1901 is a general-purpose processor or a dedicated processor. For example, it can be a baseband processor or a central processing unit for satellite communication. The baseband processor for satellite communication can be used to process satellite communication protocols and satellite communication data, and the central processing unit can be used to control the communication device (such as a baseband chip, etc.), execute computer programs, and process computer program data. The transceiver 1902 can be called a transceiver unit, a transceiver, or a transceiver circuit, etc., for implementing transceiver functions. The transceiver 1902 can include a receiver and a transmitter. The receiver can be called a receiver or a receiving circuit, etc., for implementing a receiving function; the transmitter can be called a transmitter or a transmitting circuit, etc., for implementing a transmitting function. Optionally, the communication device 1900 can also include an antenna 1903 and / or a radio frequency unit (not shown). The antenna 1903 and / or the radio frequency unit may be located inside the communication device 1900 or may be separated from the communication device 1900 , that is, the antenna 1903 and / or the radio frequency unit may be remotely or distributedly deployed.

[0576] Optionally, the communication device 1900 may include one or more memories 1904, on which instructions may be stored. The instructions may be computer programs. The computer programs may be executed on the communication device 1900 to enable the communication device 1900 to perform the methods described in the above method embodiments. Optionally, the memories 1904 may also store data. The communication device 1900 and the memories 1904 may be provided separately or integrated together.

[0577] The processor 1901 , the transceiver 1902 , and the memory 1904 may be connected via a communication bus.

[0578] In one design, the communication device 1900 can be used to perform the functions of the Beidou network device 200 in the above embodiment: the processor 1901 can be used to perform the above Figure 14 The method embodiment shown includes the following steps: parsing the SLC PDU sent by the terminal 100, generating various outbound user frames, and other functional steps and / or other processes for the technology described herein; the transceiver 1902 can be used to perform the above Figure 14 The Beidou network device 200 in the illustrated method embodiment performs functional steps related to sending and receiving and / or other processes for the technology described herein.

[0579] In any of the above designs, processor 1901 may include a transceiver for implementing receiving and transmitting functions. For example, the transceiver may be a transceiver circuit, an interface, or an interface circuit. The transceiver circuit, interface, or interface circuit for implementing the receiving and transmitting functions may be separate or integrated. The transceiver circuit, interface, or interface circuit may be used for reading and writing code / data, or the transceiver circuit, interface, or interface circuit may be used for transmitting or delivering signals.

[0580] In any of the above designs, processor 1901 may store instructions, which may be computer programs. The computer programs, when executed on processor 1901, may cause communication device 1900 to execute the method steps performed by terminal 100 in the above method embodiments. The computer programs may be fixed in processor 1901, in which case processor 1901 may be implemented by hardware.

[0581] An embodiment of the present application further provides a computer-readable storage medium, in which a computer program code is stored. When the above-mentioned processor executes the computer program code, the processor executes the method in any of the aforementioned embodiments.

[0582] An embodiment of the present application further provides a computer program product, which, when executed on a computer, enables the computer to execute the method in any of the aforementioned embodiments.

[0583] An embodiment of the present application also provides a communication device, which can exist in the form of a chip product. The structure of the device includes a processor and an interface circuit. The processor is used to communicate with other devices through a receiving circuit, so that the device executes the method in any of the aforementioned embodiments.

[0584] An embodiment of the present application further provides a Beidou communication system, including a terminal 100 and a Beidou network device 200. The terminal 100 and the Beidou network device 200 can execute the method in any of the aforementioned embodiments.

[0585] This application describes the short message communication function of the Beidou communication system. It is understood that other satellite systems may also support short message communication functions. Therefore, the method described in this application is not limited to the Beidou communication system. If other satellite systems also support short message communication functions, the method described in this application is also applicable to communications in other satellite systems.

[0586] The steps of the method or algorithm described in conjunction with the disclosure of this application can be implemented in hardware or by executing software instructions by a processor. The software instructions can be composed of corresponding software modules, which can be stored in random access memory (RAM), flash memory, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, read-only compact disks (CD-ROMs), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a core network interface device. Of course, the processor and the storage medium can also exist in the core network interface device as discrete components.

[0587] Those skilled in the art will appreciate that, in one or more of the examples above, the functions described herein can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer-readable storage media and communication media, wherein communication media include any medium that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0588] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A compact feedback method in a satellite communication system, characterized in that: include: The terminal sends N satellite link control layer protocol data units (SLC PDUs) to the satellite network device, where N is a positive integer, and the N SLC PDUs include a first SLC PDU, wherein a frame header of the first SLC PDU includes a first user identification (ID) field and an acknowledgement mode enable (AM) field, the first user ID field is used to indicate a device identification of the terminal, and the AMenable field is used to indicate an acknowledgement mode supported by the terminal at the satellite link control (SLC) layer; When the value of the AM enable field is used to indicate that the terminal supports the compact Cpack confirmation mode, the terminal receives a first compact Cpack feedback frame sent by the satellite network device, and the first Cpack feedback frame is used to indicate the reception status of the N SLC PDUs by the satellite network device; wherein the first Cpack feedback frame includes a first user compact identification CID field, the first user CID field is used to indicate the compact device identification of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

2. The method according to claim 1, characterized in that The method further comprises: When the value of the AM enable field is used to indicate that the terminal supports the complete Apack confirmation mode, the terminal receives a first complete Apack feedback frame sent by the satellite network device, and the first Apack feedback frame is used to indicate the reception status of the N SLC PDUs by the satellite network device; wherein the frame header of the first Apack feedback frame includes a second user ID field, and the second user ID field is used to indicate the device identification of the terminal, and the value of the second user ID field is the same as the value of the first user ID field.

3. The method according to claim 2, characterized in that The frame header of the first Apack feedback frame further includes a first frame type field, where the first frame type field is used to indicate that the frame type of the first Apack feedback frame is an integrity confirmation identifier Apack ACK frame or an Apack receipt frame.

4. The method according to claim 3, characterized in that The frame header of the first Apack feedback frame further includes a start identification field, wherein the start identification field is located at a starting position in the frame header of the first Apack feedback frame, and the start identification field is used to identify a starting position of the first Apack feedback frame.

5. The method according to claim 3, characterized in that The frame header of the first Cpack feedback frame includes a second frame type field and a first frame length field. The value of the second frame type field is used to indicate that the frame type of the first Cpack feedback frame is a flexible feedback frame. The first frame length field is used to indicate the total data length of the first user CID field and feedback information in the first Cpack feedback frame.

6. The method according to claim 3, characterized in that The frame header of the first Cpack feedback frame includes a third frame type field and a first frame subtype field. The value of the third frame type field is used to indicate that the frame type of the first Cpack feedback frame is a compact frame, and the value of the first frame subtype field is used to indicate that the frame subtype of the first Cpack feedback frame is a compact confirmation identifier Cpack ACK frame or a Cpack receipt frame.

7. The method according to claim 3, characterized in that The frame header of the first Cpack feedback frame includes a fourth frame type field, and a value of the fourth frame type field is used to indicate that the frame type of the first Cpack feedback frame is a CpackACK frame or a Cpack receipt frame.

8. The method according to claim 4, characterized in that The data length of the start identification field is the same as the data length of the first user CID field.

9. The method according to claim 8, characterized in that The data length of the start identification field is the first length; wherein, When the data length of the designated portion of the first length in the first user ID field is different from the value of the start identification field, the value of the first user CID field is the designated portion of the data in the first user ID field; When the data length of the designated portion of the first length in the first user ID field is the same as the value of the start identification field, the value of the first user CID field is the sum of the designated portion of the data in the first user ID field and a preset value.

10. The method according to any one of claims 1 to 9, characterized in that The terminal receives a first compact Cpack feedback frame sent by the satellite network device, specifically including: The terminal receives a first physical frame sent by the satellite network device; The terminal parses the first Cpack feedback frame from the first physical frame.

11. A compact feedback method in a satellite communication system, characterized in that: include: The satellite network device receives M SLC PDUs sent by the terminal, where M is a positive integer, and the M SLC PDUs include a first SLC PDU, wherein a frame header of the first SLC PDU includes a first user identification ID field and an AM enable field, the first user ID field is used to indicate a device identification of the terminal, and the AM enable field is used to indicate an acknowledgement mode supported by the terminal at the SLC layer; When the value of the AM enable field is used to indicate that the terminal supports the Cpack confirmation mode, the satellite network device sends a first Cpack feedback frame to the terminal, and the first Cpack feedback frame is used to indicate the reception status of the satellite network device for the M SLC PDUs; wherein the first Cpack feedback frame includes a first user CID field, the first user CID field is used to indicate the compact device identifier of the terminal, and the data length of the first user CID field is less than the data length of the first user ID field.

12. The method according to claim 11, characterized in that The method further comprises: When the value of the AM enable field is used to indicate that the terminal supports the complete Apack confirmation mode, the satellite network device sends a first complete Apack feedback frame to the terminal, and the first Apack feedback frame is used to indicate the reception status of the M SLC PDUs by the satellite network device; wherein the frame header of the first Apack feedback frame includes a second user ID field, and the second user ID field is used to indicate the device identification of the terminal, and the value of the second user ID field is the same as the value of the first user ID field.

13. The method according to claim 12, characterized in that The frame header of the first Apack feedback frame further includes a first frame type field, where the first frame type field is used to indicate that the frame type of the first Apack feedback frame is an integrity confirmation identifier Apack ACK frame or an Apack receipt frame.

14. The method according to claim 13, characterized in that The frame header of the first Apack feedback frame further includes a start identification field, wherein the start identification field is located at a starting position in the frame header of the first Apack feedback frame, and the start identification field is used to identify a starting position of the first Apack feedback frame.

15. The method according to claim 13, characterized in that The frame header of the first Cpack feedback frame includes a second frame type field and a first frame length field. The value of the second frame type field is used to indicate that the frame type of the first Cpack feedback frame is a flexible feedback frame. The first frame length field is used to indicate the total data length of the first user CID field and feedback information in the first Cpack feedback frame.

16. The method according to claim 13, characterized in that The frame header of the first Cpack feedback frame includes a third frame type field and a first frame subtype field. The value of the third frame type field is used to indicate that the frame type of the first Cpack feedback frame is a compact frame, and the value of the first frame subtype field is used to indicate that the frame subtype of the first Cpack feedback frame is a compact confirmation identifier Cpack ACK frame or a Cpack receipt frame.

17. The method according to claim 13, wherein The frame header of the first Cpack feedback frame includes a fourth frame type field, and a value of the fourth frame type field is used to indicate that the frame type of the first Cpack feedback frame is a CpackACK frame or a Cpack receipt frame.

18. The method according to claim 14, characterized in that The data length of the start identification field is the same as the data length of the first user CID field.

19. The method according to claim 18, characterized in that The data length of the start identification field is the first length; wherein, When the data length of the designated portion of the first length in the first user ID field is different from the value of the start identification field, the value of the first user CID field is the designated portion of the data in the first user ID field; When the data length of the designated portion of the first length in the first user ID field is the same as the value of the start identification field, the value of the first user CID field is the sum of the designated portion of the data in the first user ID field and a preset value.

20. The method according to any one of claims 11 to 19, characterized in that The satellite network device sending a first Cpack feedback frame to the terminal specifically includes: The satellite network device places the first Cpack general data frame into a first physical frame; The satellite network device sends the first physical frame to the terminal.

21. A satellite communication system, characterized in that: Including terminals and satellite network equipment; among which, The terminal is configured to execute the method according to any one of claims 1 to 10; The satellite network device is used to execute the method according to any one of claims 11 to 20.

22. A communication device, characterized in that: The communication device comprises one or more processors, one or more memories, and a transceiver; wherein the transceiver and the one or more memories are coupled to the one or more processors, the one or more memories are used to store computer program code, and the computer program code includes computer instructions. When the one or more processors execute the computer instructions, the communication device performs the method according to any one of claims 1 to 10.

23. The communication device according to claim 22, wherein: The communication device is a terminal.

24. A communication device, characterized in that: The communication device comprises one or more processors, one or more memories, and a transceiver; wherein the transceiver and the one or more memories are coupled to the one or more processors, the one or more memories are used to store computer program code, and the computer program code includes computer instructions. When the one or more processors execute the computer instructions, the communication device executes the method as described in any one of claims 11 to 20.

25. The communication device according to claim 24, characterized in that The communication device is a satellite network device. 26 . A computer-readable storage medium storing instructions, wherein when the instructions are executed on a computer, the computer is caused to execute the method according to claim 1 .

27. A computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium. When the instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 11 to 20.

28. A chip or chip system, applied to a terminal, characterized in that: The method comprises a processing circuit and an interface circuit, wherein the interface circuit is used to receive code instructions and transmit the code instructions to the processing circuit, and the processing circuit is used to run the code instructions to execute the method according to any one of claims 1 to 10.

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