Data transmission method for deep space reliable transmission and hop-by-hop forwarding routing and deep space routing

Abstract

The invention discloses a data transmission method for deep space reliable transmission and hop-by-hop forwarding routing and a deep space routing, and relates to the technical field of deep space networks. The method comprises the following steps: receiving a satellite data packet from a sending end, and recording the serial number continuity condition of the data packet; a reliable transmission module is constructed, if packet loss exists, a multi-track breakpoint transmission mechanism is used, intermittent link resources are fully utilized with chunk as transmission granularity, and hop-by-hop acknowledgement feedback is used at the same time to obtain the transmission condition of data frames. A multi-track breakpoint transmission mechanism is used, redundant deep space end-to-end retransmission is avoided, delay is reduced, reliability and integrity of transmission data are guaranteed, a TCP / IP (Transmission Control Protocol / Internet Protocol) system is broken through, network mobility is comprehensively supported, and a deterministic coding matrix is constructed by utilizing the property of a Cauchy matrix to guarantee successful decoding. And the decoding efficiency is improved through the sparse coding technology, and meanwhile, the transmission of coding coefficients is avoided by using the non-transmission coding vector technology, so that the header load and the bandwidth consumption are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of deep space network, and in particular to a data transmission method for deep space reliable transmission and hop-by-hop forwarding routing, and deep space routing. Background Art

[0002] As the starting point of human deep space exploration, the moon has become increasingly valuable, and a large number of exploration activities have been carried out and planned at home and abroad. Among them, the lunar poles, the back side and manned lunar exploration all require the support of lunar relay communications, which has received high international attention. At present, the main protocol systems studied and adopted in the international deep space networking are: TCP / IP-based protocol system, CCSDS-based protocol system and DTN-based protocol system. The TCP / IP mechanism commonly used on the ground has poor applicability in the deep space environment. The TCP improvement scheme has alleviated the data transmission problems caused by high latency, high bit error rate and intermittent links in deep space to a certain extent, but there is less optimization for the overall network.

[0003] In the deep space environment, the DTN protocol system adopts hop-by-hop and store-and-forward transmission, which is more suitable for deep space communication networks with high latency, frequent link disconnection, and fast link quality changes. However, the DTN protocol is built on the IP protocol and still faces mobility challenges. At the same time, the coding coefficients of each coding packet are randomly generated by the Galois field. Due to the frequent calculation of the coding coefficients, the encoding and decoding delays are high, and the transmission of the coding coefficients occupies additional bandwidth. For this reason, we propose a data transmission method and deep space routing with deep space reliable transmission and hop-by-hop forwarding routing. Summary of the invention

[0004] The purpose of the present invention is to provide a data transmission method and deep space routing for deep space reliable transmission and hop-by-hop forwarding routing, aiming to break through the TCP / IP system, fully support network mobility, and provide a deep space reliable transmission routing solution with a high decoding success rate.

[0005] According to a first aspect of the present invention, in order to achieve the above-mentioned purpose, the present invention provides the following technical solution: a data transmission method for deep space reliable transmission and hop-by-hop forwarding routing, specifically comprising the following steps:

[0006] Receive satellite data packets from the sender and record the continuity of the data packet sequence numbers;

[0007] Build a reliable transmission module. If packet loss occurs, use a multi-track breakpoint transmission mechanism to take chunks as the transmission granularity to fully utilize intermittent link resources. Use hop-by-hop confirmation feedback to learn about the transmission status of data frames, and complete the retransmission of lost data or clearing expired caches.

[0008] A hop-by-hop forwarding module is constructed, and a deterministic coding matrix and a transmission vector-free coding mechanism are used to ensure the determinism of the packet arrival rate.

[0009] Furthermore, the transmitting end is a deep space router, which is connected to the measurement and control channel through the satellite's integrated electrical unit.

[0010] Furthermore, a reliable transmission module is built. If there is packet loss, a multi-track breakpoint transmission mechanism is used to fully utilize intermittent link resources with chunk as the transmission granularity. At the same time, hop-by-hop confirmation feedback is used to obtain the transmission status of data frames, complete the retransmission of lost data or clear expired cache, as follows:

[0011] (1) When the sequence numbers of the received data packets are not continuous, the receiving end will record the packet loss;

[0012] (2) After the next orbit is powered on, the receiving end sends a feedback uplink instruction packet to the deep space router, and feeds back the lost data frame sequence number in all the currently received data packets to the deep space router in the form of an uplink instruction packet;

[0013] (3) After receiving the uplink command packet, the deep space router will promptly resend the previously lost test data, thereby recovering from packet loss, and then continue to send subsequent data content;

[0014] (4) When the Deep Space Router needs to shut down and wait for operation, the locally cached test data is saved to the hard disk storage area, and the cached data is read and restored from the hard disk when it is turned on next time.

[0015] Furthermore, the deterministic coding matrix includes a sparse coding matrix and a redundant coding matrix, which are as follows:

[0016]

[0017] In the formula, SCM N×N is the sparse coding matrix, RCM (M―N)×N is the redundant coding matrix.

[0018] Furthermore, the sparse coding matrix is ​​defined as:

[0019] SCM N×N =I N

[0020] In the formula, I N is the N-dimensional identity matrix.

[0021] Furthermore, the redundant coding matrix is ​​designed as a Cauchy matrix of size (M-N)×N to compensate for packet loss, as follows:

[0022]

[0023] u i and v i is the coefficient in the Galois field, and u i ≠v i .

[0024] Furthermore, a deterministic coding matrix and a transmission vector-free coding mechanism are used to ensure the determinism of the packet arrival rate, as follows:

[0025] (1) The original data packet is sent once in an unencoded form, and then the encoded data packet is sent;

[0026] (2) Under good network conditions, the receiver can gradually decode the original data without the need for all encoded packets in the group to arrive;

[0027] (3) Using sparse coding technology to decode data packets, the decoding complexity and delay can be reduced according to the number of uncoded messages received;

[0028] (4) In a network with poor link resources and high transmission delay, packet loss on the transmission path will lead to a lack of coding coefficients. Coding redundancy is used to compensate for packet loss during batch transmission. Each redundant coded data packet is a linear combination of all original data packets.

[0029] According to a second aspect of the present invention, the present invention provides a deep space reliable transmission and hop-by-hop forwarding routing, which is used to implement the data transmission method of the deep space reliable transmission and hop-by-hop forwarding routing, comprising:

[0030] The receiving end is used to receive the satellite data packets from the sending end and record the continuity of the data packet sequence numbers;

[0031] Reliable transmission module, using a multi-track breakpoint transmission mechanism to avoid redundant deep space end-to-end retransmissions and reduce delays, ensuring the reliability and integrity of transmitted data;

[0032] The hop-by-hop forwarding module uses a deterministic coding matrix and a transmission vector-free coding mechanism to ensure the determinism of the packet arrival rate.

[0033] According to a third aspect of the present invention, the present invention provides a terminal device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the memory stores a computer program capable of running on the processor, and when the processor loads and executes the computer program, the above-mentioned deep space reliable transmission and hop-by-hop forwarding routing data transmission method is adopted.

[0034] According to a fourth aspect of the present invention, the present invention provides a storage medium comprising computer executable instructions, which, when executed by a computer processor, are used to execute the above-mentioned data transmission method of deep space reliable transmission and hop-by-hop forwarding routing.

[0035] The present invention has at least the following beneficial effects:

[0036] 1. The present invention uses a multi-track breakpoint transmission mechanism to avoid redundant deep space end-to-end retransmission and reduce delays, ensure the reliability and integrity of transmitted data, break through the TCP / IP system, and fully support network mobility;

[0037] 2. The present invention utilizes the properties of the Cauchy matrix to construct a deterministic coding matrix (DCM) to ensure successful decoding, and improves decoding efficiency through sparse coding technology. At the same time, the non-transmission coding vector technology is used to avoid the transmission of coding coefficients, thereby reducing header load and bandwidth consumption;

[0038] 3. Compared with the DTN protocol, the present invention reduces the reliable transmission delay.

[0039] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the process of the method of the present invention;

[0041] Figure 2 This is a schematic diagram of the functional modules of the deep space routing of the present invention;

[0042] Figure 3 This is a working principle diagram of a reliable transmission module according to an embodiment of the present invention;

[0043] Figure 4 The figure is a working principle diagram of the hop-by-hop forwarding module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0045] See also Figure 1-Figure 4 The present invention provides a technical solution: a data transmission method for deep space reliable transmission and hop-by-hop forwarding routing, comprising the following steps:

[0046] S1. Receive satellite data packets from the sender and record the continuity of the data packet sequence number;

[0047] The data sending end is the deep space router, and the data receiving end is the simulation terminal. The deep space router is connected to the measurement and control channel through the satellite's integrated electrical unit. The ground flight control center receives the satellite data and forwards it to the simulation terminal.

[0048] S2. Build a reliable transmission module. If there is packet loss, use a multi-track breakpoint transmission mechanism, use chunks as the transmission granularity to make full use of intermittent link resources, and use hop-by-hop confirmation feedback to learn about the transmission status of data frames, complete the retransmission of lost data or clear expired caches, such as Figure 3 The details are as follows:

[0049] (S21) When the sequence numbers of the received data packets are not continuous, the receiving end will record the packet loss;

[0050] (S22) The receiving end sends a feedback uplink instruction packet to the deep space router after the next orbit is turned on, and feeds back the lost data frame sequence number in all currently received data packets to the deep space router in the form of an uplink instruction packet;

[0051] (S23) After receiving the uplink instruction packet, the deep space router will promptly resend the previously lost test data, thereby recovering from packet loss, and then continue to send subsequent data content;

[0052] (S24) When the Deep Space Router needs to be shut down for standby, the locally cached test data is saved to the hard disk storage area, and the cached data is read and restored from the hard disk when the Deep Space Router is turned on next time;

[0053] S3. Build a hop-by-hop forwarding module, use a deterministic coding matrix and a transmission vector-free coding mechanism to ensure the determinism of the packet arrival rate;

[0054] like Figure 4 As shown in Figure 1, the deterministic coding matrix (DCM) includes an N-dimensional sparse coding matrix (SCM) and a (M-N)×N redundant coding matrix (RCM). When using DCM, the original data packet is sent once in an uncoded form, and then the coded data packet is sent. Under relatively good network conditions, the simulation terminal software in the deep space exploration network can gradually decode the original data without the arrival of all coded data packets in the group. The decoding complexity and delay can be reduced according to the number of uncoded messages received. The SCM can be defined as:

[0055] SCM N×N =I N

[0056] In the formula, I N is the N-dimensional identity matrix.

[0057] In deep space exploration networks with extremely poor link resources and extremely high transmission delay, packet loss on the path will lead to a lack of coding coefficients. Therefore, coding redundancy is used to compensate for possible packet loss during batch transmission. Each redundant coded data packet is a linear combination of all original data packets. Considering that any two rows in the Cauchy matrix are linearly independent of each other, RCM is designed as a Cauchy matrix of size (M-N)×N to compensate for packet loss. RCM is defined as follows:

[0058]

[0059] u i and v i is the coefficient in the Galois field, and u i ≠v i ;

[0060] Therefore, the deterministic coding matrix (DCM) can be expressed as:

[0061]

[0062] In the formula, SCM N×N is the sparse coding matrix, RCM (M―N)×N is the redundant coding matrix;

[0063] Using DCM, when N coded packets are received, the simulation terminal software can successfully recover the original data and achieve packet loss recovery.

[0064] Specifically, in the traditional method, the coding coefficient is carried in the header, which increases the bandwidth overhead. In order to solve this problem, the present embodiment designs a TFCV method, in which the source and destination nodes negotiate a consistent coding matrix in advance, and the coded data packet does not need to carry the coding coefficient; in the transmission stage, the coded packet does not need to carry the entire coding coefficient, but only needs to carry the index of the coding coefficient in the DCM; when sending the first packet, the destination node obtains an original packet for each received packet, reducing the complexity of the decoding matrix calculation; the source node continuously sends redundant coded packets to the destination node, and in the destination node, the lost packets will be supplemented from the redundant coded packets until the coded packets are received; considering the harsh conditions of the deep space exploration environment and the high-loss wireless transmission link, if the destination node finally receives less than coded packets, the destination node will return a NACK containing the number of received coded packets; after receiving the NACK, the source node will send more redundant coded messages according to the coding rules, and this process continues until the original task is successfully decoded at the destination node. By utilizing retransmission, the reliable arrival of data can be guaranteed even in harsh environments.

[0065] Embodiment 2:

[0066] like Figure 2As shown, this embodiment provides a deep space reliable transmission and hop-by-hop forwarding routing, which is used to implement the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing described in Embodiment 1, including:

[0067] The receiving end is used to receive the satellite data packets from the sending end and record the continuity of the data packet sequence numbers;

[0068] Reliable transmission module, using a multi-track breakpoint transmission mechanism to avoid redundant deep space end-to-end retransmissions and reduce delays, ensuring the reliability and integrity of transmitted data;

[0069] The hop-by-hop forwarding module uses a deterministic coding matrix and a transmission vector-free coding mechanism to ensure the determinism of the packet arrival rate.

[0070] It should be noted that the deep space route described in this embodiment was successfully launched in March 24 and entered the lunar orbit. It completed experiments such as reliable moon-to-earth transmission, adaptive coding, and multi-terminal earth-to-moon communication. The reliable moon-to-earth transmission delay is reduced by 20% compared with the international mainstream DTN protocol. It has the ability to support up to 1,000 detection terminals to access, and the exchange rate can reach 100Mbps. It provides useful reference and basis for major engineering tasks such as the International Lunar Research Station and the Queqiao Telecommunications Integrated Constellation System.

[0071] Specifically, the above-mentioned receiving end, reliable transmission module and hop-by-hop forwarding module can be embedded in a computer processing system. The computer calls the above-mentioned modules to complete the task of accurately identifying the road surface at night based on the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing provided above; the above-mentioned receiving end, reliable transmission module and hop-by-hop forwarding module can perform operations according to the specific steps given in the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing.

[0072] It should be noted that it should be understood that the division of the various modules of the above system is only the division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated, and these modules can all be implemented in the form of software calling through processing elements; they can also be all implemented in the form of hardware; some modules can also be implemented in the form of software calling through processing elements, and some modules can be implemented in the form of hardware. For example, the light enhancement module can be a separately established processing element, or it can be integrated in a chip of the above-mentioned device. In addition, it can also be stored in the memory of the above-mentioned device in the form of program code, and called and executed by a processing element of the above-mentioned device. The functions of the above signal processing module, and the implementation of other modules is similar. In addition, these modules can be fully or partially integrated together, or they can be implemented independently. The processing element described here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules can be completed by the hardware integrated logic circuit in the processor element or software instructions.

[0073] For example, the above modules may be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASIC), or one or more digital singnal processors (DSP), or one or more field programmable gate arrays (FPGA). For another example, when a module is implemented in the form of a processing element scheduling program code, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processors that can call program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0074] Embodiment three:

[0075] The present invention provides a terminal device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the memory stores a computer program capable of running on the processor, and when the processor loads and executes the computer program, the above-mentioned deep space reliable transmission and hop-by-hop forwarding routing data transmission method is adopted.

[0076] It should be noted that the terminal device can be a computer device such as a desktop computer, a laptop computer or a cloud server, and the terminal device includes but is not limited to a processor and a memory. For example, the terminal device can also include input and output devices, network access devices and buses.

[0077] Furthermore, the processor may adopt a central processing unit (CPU). Of course, according to actual usage, other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. may also be adopted. The general-purpose processor may adopt a microprocessor or any conventional processor, etc., and the present application does not impose any restrictions on this.

[0078] Embodiment 4:

[0079] The present invention provides a storage medium containing computer executable instructions, which are used to execute the above-mentioned data transmission method of deep space reliable transmission and hop-by-hop forwarding routing when executed by a computer processor.

[0080] Among them, the computer program can be stored in a computer-readable medium, the computer program includes computer program code, the computer program code can be in the form of source code, object code, executable file or certain middleware, etc. The computer-readable medium includes any entity or device that can carry the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the computer-readable medium includes but is not limited to the above-mentioned components.

[0081] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0082] For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. When an element is referred to as being "assembled on", "installed on", "fixed on" or "set on" another element, it can be directly on the other element or there can also be a centered element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a centered element at the same time. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are only for illustrative purposes and are not intended to be the only implementation method.

[0083] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0084] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

Claims

1. A data transmission method for deep space reliable transmission and hop-by-hop forwarding routing, characterized in that: The following steps are involved: Receive satellite data packets from the sender and record the continuity of the data packet sequence numbers; Build a reliable transmission module. If packet loss occurs, use a multi-track breakpoint transmission mechanism to take chunks as the transmission granularity to fully utilize intermittent link resources. Use hop-by-hop confirmation feedback to learn about the transmission status of data frames, and complete the retransmission of lost data or clearing expired caches. A hop-by-hop forwarding module is constructed, and a deterministic coding matrix and a transmission vector-free coding mechanism are used to ensure the determinism of the packet arrival rate.

2. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 1, characterized in that: The transmitting end is a deep space router, which is connected to the measurement and control channel through the satellite's integrated electrical unit.

3. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 2 is characterized in that: Build a reliable transmission module. If there is packet loss, use a multi-track breakpoint transmission mechanism to take chunks as the transmission granularity to make full use of intermittent link resources. At the same time, use hop-by-hop confirmation feedback to learn about the transmission status of data frames, and complete the retransmission of lost data or clearing of expired caches. The details are as follows: (1) When the sequence numbers of the received data packets are not continuous, the receiving end will record the packet loss; (2) After the next orbit is powered on, the receiving end sends a feedback uplink instruction packet to the deep space router, and feeds back the lost data frame sequence number in all the currently received data packets to the deep space router in the form of an uplink instruction packet; (3) After receiving the uplink command packet, the deep space router will promptly resend the previously lost test data, thereby recovering from packet loss, and then continue to send subsequent data content; (4) When the Deep Space Router needs to shut down and wait for operation, the locally cached test data is saved to the hard disk storage area, and the cached data is read and restored from the hard disk when it is turned on next time.

4. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 3 is characterized by: The deterministic coding matrix includes an N-dimensional sparse coding matrix and a (M-N)×N redundant coding matrix, which is as follows: In the formula, SCM N×N is the sparse coding matrix, RCM (M―N)×N is the redundant coding matrix.

5. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 4 is characterized by: The sparse coding matrix is ​​defined as: SCM N×N =I N In the formula, I N is the N-dimensional identity matrix.

6. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 5 is characterized by: The redundant coding matrix is ​​designed as a Cauchy matrix of size (M-N)×N to compensate for packet loss, as follows: u i and v i is the coefficient in the Galois field, and u i ≠v i .

7. The data transmission method of deep space reliable transmission and hop-by-hop forwarding routing according to claim 6 is characterized in that ,Using a deterministic coding matrix and a transmission vector-free coding mechanism, the ,determinism of the packet arrival rate is ensured, as follows: (1) The original data packet is sent once in an unencoded form, and then the encoded data packet is sent; (2) Under good network conditions, the receiver can gradually decode the original data without the need for all encoded packets in the group to arrive; (3) Using sparse coding technology to decode data packets, the decoding complexity and delay can be reduced according to the number of uncoded messages received; (4) In a network with poor link resources and high transmission delay, packet loss on the transmission path will lead to a lack of coding coefficients. Coding redundancy is used to compensate for packet loss during batch transmission. Each redundant coded data packet is a linear combination of all original data packets.

8. A deep space reliable transmission and hop-by-hop forwarding routing, used to implement the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing as claimed in any one of claims 1 to 7, characterized in that: include: The receiving end is used to receive the satellite data packets from the sending end and record the continuity of the data packet sequence numbers; Reliable transmission module, using a multi-track breakpoint transmission mechanism to avoid redundant deep space end-to-end retransmissions and reduce delays, ensuring the reliability and integrity of transmitted data; The hop-by-hop forwarding module uses a deterministic coding matrix and a transmission vector-free coding mechanism to ensure the determinism of the packet arrival rate.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that: The memory stores a computer program that can be run on the processor. When the processor loads and executes the computer program, the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing described in any one of claims 1 to 7 is adopted.

10. A storage medium containing computer executable instructions, characterized in that: When the computer executable instructions are executed by a computer processor, they are used to execute the data transmission method of deep space reliable transmission and hop-by-hop forwarding routing as described in any one of claims 1 to 7.

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