Spacecraft low-characteristic multi-source load data stream processing method and system

Abstract

The invention discloses a spacecraft low-feature multi-source load data stream processing method and system, and the method comprises the steps: receiving data transmission frame data, and extracting the data in a load data region according to a data transmission frame format; and sorting the load data of different sources from all the load data, and storing the sorted load data according to the packet header feature words. According to the method, for low-feature load data, two-time sorting is not needed, a secondary feature word is extracted from an effective data area of the load data, meanwhile, the packet header feature word and the secondary feature word are recognized, and the load packet can be correctly found through one-time comparison. And the processing efficiency and the processing accuracy are improved.

Description

Technical Field

[0001] The present invention relates to a spacecraft low-signature multi-source payload data stream processing method and system, belonging to the field of payload data processing. Background Art

[0002] Payload is a subsystem carried by the spacecraft to achieve application effectiveness. It not only includes various imaging payloads, but also includes payload subsystems with application effectiveness that assist in image quality improvement, environmental perception, signal transmission, etc. It is an important basis for reflecting the on-orbit application effectiveness of the satellite.

[0003] Satellite payload data is generally processed by the data transmission subsystem according to the frame format and then transmitted in the digital transmission frame format. Most of the payload data is transmitted on the satellite in different channels and stored in the digital transmission data of different channels. By sorting out the digital transmission data of different channels, different payload data can be sorted out. However, there are also payload data from multiple sources transmitted on the same channel on the satellite, and it is necessary to sort out the payload data from different sources from the digital transmission frame of the same channel. At present, the processing of data in the digital transmission frame format is usually performed by identifying the header feature word of the data transmission, searching and sorting. However, for payload data, the header feature word occupies a short byte length, and it is easy for the payload data packet header feature word to appear in other data. It is easy to make sorting errors by searching only by the header feature word. At present, the sorting of this low-feature multi-source payload data is performed by sorting once based on the header feature word, and then extracting the data whose length meets the protocol from the sorted data. Such processing has a slow sorting speed and low efficiency. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and provide a method and system for streaming processing of low-signature multi-source payload data of a spacecraft. For low-signature payload data, there is no need for two sortings, and a secondary signature word is extracted from the valid data area of ​​the payload data. The header signature word and the secondary signature word are identified at the same time, so that the payload package can be correctly found by a single comparison.

[0005] The technical solution of the present invention is: a method for streaming data processing of low-signature multi-source payloads of spacecraft, comprising:

[0006] Receive data transmission frame data, and extract data in the payload data area according to the data transmission frame format;

[0007] The payload data from different sources are sorted out from all the payload data, and the sorted payload data are stored according to the packet header feature word.

[0008] The payload data from different sources are sorted out from all the payload data according to the packet header signature, the packet header signature position, the secondary signature, the secondary signature position, and the packet length.

[0009] The process of sorting out the payload data from different sources from all the payload data and storing the sorted payload data according to the packet header signature includes:

[0010] 1) Establish a mapping table for different source payload data, including header signature, header signature position, secondary signature, secondary signature position, and packet length;

[0011] 2) According to the established mapping table, read from the first byte of all the payload data that has not been read, read the payload data into the original payload data storage area, and determine whether the data length in the original payload data storage area is greater than or equal to the set threshold condition; if it is greater than or equal to the set threshold condition, proceed to step 3), otherwise continue reading; if the last data length read is still less than the set threshold condition, then directly start sorting the payload data from step 3) until all the header feature words and the second-class feature words cannot be found, and then the sorting ends;

[0012] 3) Start sorting the data in the original payload data storage area, search for the payload header signature in the data in the original payload data storage area, if the header signature is found, search for the secondary signature at the secondary signature position corresponding to the header signature, if the header signature is not found, continue to search backward until all the data in the original payload data storage area is found; if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); if the secondary signature is found, start from the header signature, extract the payload data of the source according to the payload data format protocol, and enter step 4), if the secondary signature is not found, continue to search backward until all the data in the original payload data storage area is found, if the header signature is not found, clear all the data in the original payload data storage area and return to step 2);

[0013] 4) Classifying and storing the payload data with different header signatures according to the payload data from different sources;

[0014] 5) Clear the extracted part of the payload data in the original payload data storage area, retain the remaining original payload data, and return to step 2) until the processing of all payload data is completed.

[0015] The threshold condition is that the data length in the original payload data storage area is greater than or equal to the length of the longest two packets of payload data.

[0016] A spacecraft low-signature multi-source payload data stream processing system, comprising a data receiving module, a data sorting module, and a data storage module;

[0017] A data receiving module receives data transmission frame data and extracts a payload data area according to a virtual channel identifier in the data transmission frame format;

[0018] A data sorting module sorts the extracted load data;

[0019] The data storage module stores the payload data according to the packet header signature.

[0020] The data sorting module sorts the payload data according to the packet header feature word, the packet header feature word position, the secondary feature word, the secondary feature word position, and the packet length.

[0021] The data sorting module sorts the payload data according to the packet header feature word, the packet header feature word position, the secondary feature word, the secondary feature word position, and the total packet length, including:

[0022] 1) Establish a mapping table for different source payload data, including header signature, header signature position, secondary signature, secondary signature position, and packet length;

[0023] 2) According to the established mapping table, read from the first byte of all the payload data that has not been read, read the payload data into the original payload data storage area, and determine whether the data length in the original payload data storage area is greater than or equal to the set threshold condition; if it is greater than or equal to the set threshold condition, proceed to step 3), otherwise continue reading; if the last data length read is still less than the set threshold condition, then directly start sorting the payload data from step 3) until all the header feature words and the second-class feature words cannot be found, and then the sorting ends;

[0024] 3) Start sorting the data in the original payload data storage area, search for the payload header signature in the data in the original payload data storage area, if the header signature is found, search for the secondary signature at the secondary signature position corresponding to the header signature, if the header signature is not found, continue to search backward until all the data in the original payload data storage area is found; if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); if the secondary signature is found, start from the header signature, extract the payload data of the source according to the payload data format protocol, and enter step 4), if the secondary signature is not found, continue to search backward until all the data in the original payload data storage area is found, if the header signature is not found, clear all the data in the original payload data storage area and return to step 2);

[0025] 4) Clear the extracted part of the payload data in the original payload data storage area, retain the remaining original payload data, and return to step 2) until the processing of all payload data is completed.

[0026] The threshold condition is that the data length in the original payload data storage area is greater than or equal to the length of the longest two packets of payload data.

[0027] The advantages of the present invention compared with the prior art are:

[0028] 1. The prior art generally only recognizes a header signature to perform a data extraction first, and then filters the data that meets the packet length according to the protocol. The payload packet generally has a small number of header signature bytes, and there are header signatures in non-header locations. It is easy to extract wrong data when performing a single extraction based on the header signature. The present invention uses the header signature and the secondary signature to generally achieve a single extraction of the correct data.

[0029] 2. The present invention uses the header feature word and the secondary feature word for direct extraction, and can extract correctly in one time without the need for secondary screening according to the protocol, thereby improving the processing rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure is a flow chart of the steps of the method for streaming data of low-signature multi-source payloads of spacecraft.

[0031] Figure 2 This is the module diagram of the spacecraft low-signature multi-source payload data streaming processing system. DETAILED DESCRIPTION

[0032] The present invention provides a method and system for streaming processing of low-signature multi-source payload data of spacecraft. For low-signature payload data, there is no need for secondary sorting. A secondary signature word is extracted from the valid data area of ​​the payload data, and the header signature word and the secondary signature word are identified at the same time, so that the payload package can be correctly found by a single comparison.

[0033] like Figure 1 As shown, the method of the present invention comprises:

[0034] 1. Data reception: Receive satellite data transmission and split it into valid data area. The splitting needs to refer to the satellite data transmission downlink data format protocol. Table 1 is an example of a data transmission downlink data format. The downlink valid data area is the BPDU bit stream data area.

[0035] Table 1 An example of a data transmission downlink data format

[0036]

[0037] 2. Data sorting: sorting out the load data from different sources from all the load data

[0038] 3. Data storage: the sorted payload data is stored according to the source. The storage space should at least ensure the normal storage of the payload data transmitted by the satellite once.

[0039] The data sorting steps include:

[0040] 1. Establish a mapping table of packet header signature, packet header signature position, secondary signature, secondary signature position, and total packet length for different source payload data;

[0041] The payload data from different sources is determined according to the actual use status of the user. The data format needs to refer to the satellite data format protocol, and the data format protocol is summarized into a mapping table, as shown in Table 2;

[0042] Table 2 An example of a mapping table format

[0043]

[0044] 2. Start reading from the first byte of the unread payload data and read the payload data into the original payload data storage area. In order to ensure that a complete frame of payload data can be obtained, determine that the data length in the storage area is greater than or equal to the length of the longest 2 frames of payload data before proceeding to the next step.

[0045] 3. Search for the payload header signature in the data in the storage area. You can match it according to the common divisor of the header signatures of all packets in the mapping table, thereby shortening the header matching time (for example, if some headers are 2 bytes and some are 4 bytes, then match 2 bytes at a time; if some headers are 2 bytes and some are 3 bytes, then match 1 byte at a time). If the header signature is found, search for the corresponding secondary signature at the secondary signature position corresponding to the header signature. If the secondary signature is found, start from the header signature and extract the payload data of the source according to the total packet length.

[0046] 4. According to the payload data from different sources, the payload data with different header signatures are classified and stored. The payload data with the same header signature are placed in the same storage file.

[0047] 5. Clear the extracted part of the original payload data storage area, keep the remaining data, and return to step 2 to restart reading data, connect with the remaining data, and again determine whether the data length in the storage area is greater than or equal to the length of the longest 2 frames of payload data, and then proceed to the next step;

[0048] 6. If the data length in the storage area is less than the length of the longest 2-frame payload data after the payload data to be read is completed, it means that the data has been read and the data in the storage area is the last valid data. Then, the payload data is sorted directly from step 3 until all the header signatures and the second-class signatures cannot be found, indicating that there is no valid payload data and the sorting is finished.

[0049] like Figure 2As shown, the present invention also provides a spacecraft low-signature multi-source payload data streaming processing system, including a data receiving module, a data sorting module, and a data storage module. The data receiving module is used to receive digital transmission frame data and extract the payload data area according to the digital transmission frame format. The payload data area extracted here is the payload data of different sources processed in the subsequent sorting process; the data sorting module is used to sort the payload data by source and separate the payload data by source; the data storage module is used to store the payload data by source and store the sorted payload data on a disk.

[0050] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for processing spacecraft low-signature multi-source payload data stream, characterized in that: include: Receive data transmission frame data, and extract data in the payload data area according to the data transmission frame format; The payload data from different sources are sorted out from all the payload data, and the sorted payload data are stored according to the packet header feature word.

2. A method for processing spacecraft low-signature multi-source payload data stream according to claim 1, characterized in that: The payload data from different sources are sorted out from all the payload data according to the packet header signature, the packet header signature position, the secondary signature, the secondary signature position, and the packet length.

3. A method for processing spacecraft low-signature multi-source payload data stream according to claim 2, characterized in that: The process of sorting out the payload data from different sources from all the payload data and storing the sorted payload data according to the packet header signature includes: 1) Establish a mapping table for different source payload data, including header signature, header signature position, secondary signature, secondary signature position, and packet length; 2) According to the established mapping table, read from the first byte of all the payload data that has not been read, read the payload data into the original payload data storage area, and determine whether the data length in the original payload data storage area is greater than or equal to the set threshold condition; if it is greater than or equal to the set threshold condition, proceed to step 3), otherwise continue reading; if the last data length read is still less than the set threshold condition, then directly start sorting the payload data from step 3) until all the header feature words and the second-class feature words cannot be found, and then the sorting ends; 3) Start sorting the data in the original payload data storage area, search for the payload header signature in the data in the original payload data storage area, if the header signature is found, search for the secondary signature at the secondary signature position corresponding to the header signature, if the header signature is not found, continue to search backward until all the data in the original payload data storage area is found; if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); if the secondary signature is found, start from the header signature, extract the payload data of the source according to the payload data format protocol, and enter step 4), if the secondary signature is not found, continue to search backward until all the data in the original payload data storage area is found, if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); 4) Classifying and storing the payload data with different header signatures according to the payload data from different sources; 5) Clear the extracted part of the payload data in the original payload data storage area, retain the remaining original payload data, and return to step 2) until the processing of all payload data is completed.

4. A method for processing spacecraft low-signature multi-source payload data stream according to claim 3, characterized in that: The threshold condition is that the data length in the original payload data storage area is greater than or equal to the length of the longest two packets of payload data.

5. A spacecraft low-signature multi-source payload data streaming processing system, characterized in that: It includes a data receiving module, a data sorting module and a data storage module; A data receiving module receives data transmission frame data and extracts a payload data area according to a virtual channel identifier in the data transmission frame format; A data sorting module sorts the extracted load data; The data storage module stores the payload data according to the packet header signature.

6. A spacecraft low-signature multi-source payload data streaming processing system according to claim 5, characterized in that: The data sorting module sorts the payload data according to the packet header feature word, the packet header feature word position, the secondary feature word, the secondary feature word position, and the packet length.

7. A spacecraft low-signature multi-source payload data streaming processing system according to claim 6, characterized in that: The data sorting module sorts the payload data according to the packet header feature word, the packet header feature word position, the secondary feature word, the secondary feature word position, and the total packet length, including: 1) Establish a mapping table for different source payload data, including header signature, header signature position, secondary signature, secondary signature position, and packet length; 2) According to the established mapping table, read from the first byte of all the payload data that has not been read, read the payload data into the original payload data storage area, and determine whether the data length in the original payload data storage area is greater than or equal to the set threshold condition; if it is greater than or equal to the set threshold condition, proceed to step 3), otherwise continue reading; if the last data length read is still less than the set threshold condition, then directly go from step 3) Start sorting the payload data until all packet header signatures and second-class signatures cannot be found, and then stop sorting; 3) Start sorting the data in the original payload data storage area, search for the payload header signature in the data in the original payload data storage area, if the header signature is found, search for the secondary signature at the secondary signature position corresponding to the header signature, if the header signature is not found, continue to search backward until all the data in the original payload data storage area is found; if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); if the secondary signature is found, start from the header signature, extract the payload data of the source according to the payload data format protocol, and enter step 4), if the secondary signature is not found, continue to search backward until all the data in the original payload data storage area is found, if the header signature is not found, clear all the data in the original payload data storage area and return to step 2); 4) Clear the extracted part of the payload data in the original payload data storage area, retain the remaining original payload data, and return to step 2) until the processing of all payload data is completed.

8. A spacecraft low-signature multi-source payload data streaming processing system according to claim 7, characterized in that: The threshold condition is that the data length in the original payload data storage area is greater than or equal to the length of the longest two packets of payload data.

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