An on-board storage and retrieval method supporting packet storage and control

Abstract

The application discloses a kind of on-board storage and acquisition method supporting packet storage and control, by setting APID (application process identification) control structure and packet storage selection control structure in on-board computer, i.e. by changing storage enable flag, can be according to different application requirements, realize the storage or not (add or delete) of source packet;By setting different packet storage area length, and selecting the corresponding packet storage area according to the source packet length, and filling the unoccupied space, realize the fixed length of source packet occupied space, selectively store and read specified source packet data.The method flexibly adds the storage and acquisition of some source packets, or no longer stores and acquires a source packet, greatly improves the flexibility of source packet storage and acquisition, solves the problem that the original method cannot selectively store and retrieve source packets.

Description

Technical Field

[0001] This invention relates to an on-board storage and retrieval method that supports packet storage and control, and belongs to the field of aerospace computer technology. Background Technology

[0002] The onboard computer needs to store data from multiple devices, including the onboard computer itself, the control computer, payload equipment, cameras, and other sensors. When the satellite is outside the ground control area and invisible, this data is stored. When the satellite enters the ground control area, the stored data is retrieved and transmitted. Additionally, satellites requiring autonomous mission operation need to store mission data, which can be retrieved, analyzed, and processed when needed.

[0003] Existing literature and patent methods focus primarily on data storage capacity and speed, with limited research on data storage formats and no mention of data storage selection and control methods. Onboard data storage typically uses Virtual Channel Frames (VC frames). VC frames are fixed-length data formats containing a header and a data field. The onboard computer encapsulates the source packet data into a Multiplexer Unit (MPDU), then further encapsulates it into the data field of the VC frame for storage, and implements VC frame-based retrieval functionality. This fixed-length VC frame approach is relatively easy to implement.

[0004] This approach has the following drawbacks:

[0005] 1) The data granularity of storage and retrieval based on VC frames is too large, making it difficult to achieve application-based data retrieval. Since the stored objects are all VC frames, retrieving application data requires retrieving each VC frame frame by frame, then parsing the multiplexing unit (MPDU) in the data field, and reconstructing the source packet data in the MPDU (source packet data can span MPDUs). This consumes temporary storage resources exceeding the onboard RAM space, and the retrieval time exceeds the usage requirements, making application-based data retrieval difficult. Even if application data reconstruction and retrieval are achieved for certain specific VC frames, the temporary storage resources consumed and the retrieval time are very large, resulting in low efficiency.

[0006] 2) Insufficient support for application data storage control. When storage resources are insufficient, the ground no longer focuses on certain application data, or only focuses on certain application data for a certain period of time, it is possible to choose to store certain application data and not store application data that is not of interest. However, the traditional method cannot set whether application data is stored according to needs.

[0007] 3) When satellite health data is abnormal, traditional methods cannot dynamically select and store this abnormal data, resulting in the loss of abnormal data and the inability to repair the resulting faults in a timely manner.

[0008] Therefore, traditional on-board storage functions cannot achieve source packet storage selection and control, and cannot selectively store and retrieve specified source packet data according to ground requirements or autonomous health management needs. To overcome the shortcomings of existing technologies, it is necessary to research an on-board storage and retrieval method that supports packet storage and control, and solve the problems of packet storage retrieval and packet storage selection control. Summary of the Invention

[0009] In view of this, the present invention provides an on-board storage and retrieval method that supports packet storage and control, solving the problem that existing methods cannot store and retrieve application data. By setting APID control structure and packet storage selection control structure, specified source packet data can be selectively stored, read and deleted.

[0010] A method for onboard storage and retrieval supporting packet storage and control includes: first, establishing multiple packet storage areas with fixed-length types in the onboard computer; then, setting an Application Procedure Identifier (APID) control structure to record storage enable flags, service types, and subtypes; next, setting a packet storage selection control structure to record storage area IDs, source packet length types, and APID control structures; and finally, implementing source packet operations according to actual needs.

[0011] (1) Modify storage status: By ground annotation or self-modification, the storage enable flag of APID in the packet storage selection control structure is modified to "store" or "not store", so as to modify the storage status of existing source packets and abnormal source packets.

[0012] (2) Storage: For a newly received source packet, if the packet storage selection control structure contains the same APID business type and subtype as the source packet, and the "storage enable flag" is "storage", then the source packet is stored; the space not occupied by the source packet data is filled.

[0013] (3) Obtain and read source packets, retrieve and obtain partial data in source packets: directly search for source packets by using the attributes set in the application process identification control structure and packet storage selection control structure, or directly obtain data in source packets by using the specified offset;

[0014] (4) Deletion: When deletion is required, first find the source package and delete it.

[0015] Preferably, the APID control structure includes APID, storage enable flag, device source, service type and number of subtypes M, and M service types and subtypes.

[0016] Preferably, the packet storage selection control structure includes storage area ID, source packet length type, number of APIDs N, and N APID control structures.

[0017] Preferably, for existing source packets, the storage state of the source packets can be modified by changing the storage enable flag of APID in the packet storage selection control structure to "store" or "not store"; for abnormal source packets, the storage of abnormal source packets can be achieved by manually modifying the storage enable flag of APID in the packet storage selection control structure to "store".

[0018] Preferably, the specific method for storing newly received source packets is as follows:

[0019] Preferably, if there is a storage item in the packet storage selection control structure that has the same APID, service type and subtype as the source packet, and the storage enable flag is "storage", then the source packet is stored; and when storing, first obtain the storage area ID corresponding to the storage item, and then store the time code, device source and source packet in sequence. If the effective length of the source packet is less than the length type of the source packet in the storage area, then the part not occupied by the source packet data is filled with 0x00.

[0020] A better method for obtaining and reading the source package is:

[0021] Based on the APID, business type, and subtype of the required source package, search for storage items with the same APID, business type, and subtype in the package storage selection control structure, obtain the storage area ID corresponding to the storage item, and then search for the package storage area corresponding to the storage area ID:

[0022] Method 1: Locate and read the source package that has the same APID, business type, and subtype as the required source package;

[0023] Method 2: Based on the device source and timecode range stored when the source packet is stored, search for and read all source packets in the packet storage area that belong to the device source or whose timecode is within the time range.

[0024] Ideally, retrieve and obtain a portion of the data from the source package:

[0025] Based on the APID, business type, and subtype of the required source packet, search for a storage item with the same APID, business type, and subtype in the packet storage selection control structure. In the packet storage area corresponding to the storage area ID, search for a source packet with the same APID, business type, and subtype as the required source packet. Based on the specified offset, directly obtain the data in the source packet.

[0026] A better method for deleting the source package is:

[0027] Based on the APID, business type, and subtype of the required source package, search for storage items with the same APID, business type, and subtype in the package storage selection control structure, obtain the storage area ID corresponding to the storage item, and then search for the package storage area corresponding to the storage area ID:

[0028] Method 1: Find and delete the source package that has the same APID, business type, and subtype as the required source package;

[0029] Method 2: Based on the device source and timecode range stored when storing the required source packets, find all source packets in the packet storage area that belong to the device source or whose timecodes are within the time range, and delete them.

[0030] Preferably, the source packet length is 64 bytes, 128 bytes, 256 bytes, 512 bytes, 1024 bytes, 2048 bytes, 4096 bytes, 8192 bytes, or 16384 bytes, or can be extended as needed.

[0031] Beneficial effects

[0032] 1. By setting up APID (Application Process Identifier) ​​control structures and packet storage selection control structures in the onboard computer, i.e., by changing the storage enable flag, the storage or non-storage (addition or deletion) of source packets can be implemented according to different application requirements. By setting different packet storage area lengths and selecting the corresponding packet storage area according to the source packet length, and filling unoccupied space, the source packet occupancy space is fixed, and the specified source packet data can be selectively stored and retrieved. This method flexibly adds the storage and retrieval of certain source packets, or stops storing and retrieving certain source packets, greatly improving the flexibility of source packet storage and retrieval, and solving the problem that the original method could not selectively store and retrieve source packets.

[0033] 2. By setting up the APID control structure and adding a storage enable flag, the storage status of source packets can be modified via ground-based annotations. Specifically, when the storage enable flag is changed to "store," the data can be stored; when it is changed to "do not store," the data can be deleted. This allows for selective storage of application data and non-storage of data from applications that are not of interest when storage resources are insufficient, when the ground system is no longer focused on certain application data, or when only certain application data is of primary concern for a given period.

[0034] 3. The packet storage selection control structure can be set to associate the source packet with the storage area ID based on APID, business type, business subtype, and storage area ID. This allows for quick location of the packet storage area and execution of source packet retrieval, reading, and deletion functions.

[0035] 4. When satellite health data is abnormal, the storage enable flag can be modified to select and store abnormal data source packages, which facilitates ground analysis and resolution of the abnormality problem, and solves the problem of abnormal data loss in the original method.

[0036] 5. When a new source packet is received, the corresponding storage area is selected according to the length of the source packet, and the unoccupied part of the storage area is filled with 0x00, so that the space occupied by each source packet is of fixed length. Therefore, for each piece of stored data in the packet storage area, the time code, device origin, APID in the source packet, business type, subtype, and offset of the source packet data are all in a fixed position, which can be quickly retrieved, greatly reducing the storage time and retrieval time, and improving storage and retrieval efficiency.

[0037] 6. Because the APID control structure and packet storage selection control structure are fixed, when a specific source packet is needed, it is only necessary to search for a storage item with the same APID, service type, and subtype in the packet storage selection control structure based on the required source packet's APID, service type, and subtype. The storage area ID corresponding to the storage item is then obtained, and the search is performed within the storage area according to the required source packet's APID, service type, and subtype. This is convenient and fast. Furthermore, since information such as timecode and device origin is recorded, users can also search based on this information, offering high flexibility.

[0038] 7. Because padding is applied during storage, each source packet occupies a fixed amount of space with a fixed offset. Therefore, after finding the source packet, users can directly retrieve the required data by using the offset, enabling them to quickly locate and obtain application data.

[0039] 8. To ensure rapid retrieval of specific data within a source packet, this project requires a fixed-length storage space for each source packet. Therefore, based on the potential length of the source packet data, a corresponding source packet length type is assigned to the packet storage area. These types include 64 bytes, 128 bytes, 256 bytes, 512 bytes, 1024 bytes, 2048 bytes, 4096 bytes, 8192 bytes, 16384 bytes, or longer. This ensures a fixed-length storage space by setting the source packet length type. Furthermore, by selecting a storage area closest to the effective data length of the source packet, less 0x00 is used to fill unused space, maximizing storage space utilization. The appropriate storage area can be selected based on the actual data requirements, avoiding storage waste. Attached Figure Description

[0040] Figure 1 This is a diagram of the storage selection control structure of the present invention.

[0041] Figure 2 This is a process diagram of the on-board storage and retrieval method of the present invention. Detailed Implementation

[0042] The implementation of the method of the present invention will be described below with reference to the accompanying drawings and embodiments.

[0043] This invention provides an on-board storage and retrieval method that supports packet storage and control, such as... Figure 1 As shown, by setting the APID (Application Process Identifier) ​​control structure and packet storage selection control structure in the onboard computer, that is, by changing the storage enable flag, the storage or non-storage (addition or deletion) of source packets can be achieved; by setting different packet storage area lengths and selecting the corresponding packet storage area according to the source packet length, and filling the unoccupied space, the source packet occupancy space is fixed, thus enabling fast retrieval. Figure 2 As shown, the specific method is as follows:

[0044] Step 1: Establish multiple packet stores in the onboard computer. Each packet store is configured with a source packet length type.

[0045] One package storage area corresponds to one file. Source packages are stored in the package storage area, which is uniquely identified by a "storage area ID". To improve storage and retrieval efficiency, source packages are categorized by length, with various length types available, including 64 bytes, 128 bytes, 256 bytes, 512 bytes, 1024 bytes, 2048 bytes, 4096 bytes, 8192 bytes, 16384 bytes, and longer lengths. When storing a source package in the package storage area, the closest available length type is selected. For example, the source package length types are defined as follows:

[0046] Source packet length Source packet length type 64 bytes 0x11 128 bytes 0x22 256 bytes 0x33 512 bytes 0x44 1024 bytes 0x55 2048 bytes 0x66 4096 bytes 0x77 8192 bytes 0x88 Longer byte 0x99

[0047] Step 2: Configure the Application Process Identifier (APID) control structure, including APID, storage enable flag, device source, service type, and the number of M service types and subtypes. By changing the storage enable flag, the storage or non-storage status of the source packet is controlled (added or deleted).

[0048] For example, the APID control structure 1 setting example is as follows:

[0049]

[0050]

[0051] The following is an example of APID control structure 2 settings:

[0052] APID 0x1B3 Storage enable flag 0x77 Equipment source 0x05 (Payload Computer) Number of business type subtypes M 1 Business Type 1 0x02 Subtype 1 0x04

[0053] Step 3: Configure the packet storage selection control structure. The packet storage selection control structure includes the storage area ID, source packet length type, number of APID control structures N, and N APID control structures.

[0054] For example, the following is an example of the packet storage selection control structure settings:

[0055] Storage ID 0x01 Source packet length type 0x33 Number of APIDs N 2 N APID control structures The above two APID control structures

[0056] Step 4: Implement control and processing of the source package according to actual needs.

[0057] S41. Modify the storage status of an existing source package, that is, modify the storage enable flag of the source package:

[0058] The ground-based command modifies the settings in the packet storage selection control structure, changing the source packet storage status by setting the "storage enable flag" to "store" or "not store" based on the APID. Furthermore, APIDs can be added or deleted, along with their corresponding service types and subtypes.

[0059] S42. Processing of abnormal source packet data:

[0060] When the onboard computer receives source packet data and detects that the health identifier data in the source packet is abnormal, it autonomously modifies the settings in the packet storage selection control structure and sets the "storage enable flag" of the APID to "storage".

[0061] For example: If abnormal health flag data of the payload computer is detected, modify the "Storage Enable Flag" to "Storage" (0x88), as follows:

[0062] APID 0x1B3 Storage enable flag 0x88 Equipment source 0x05 (Payload Computer) Number of business type subtypes M 1 Business Type 1 0x02 Subtype 1 0x04

[0063] S43. Store source packet data:

[0064] The source packet is stored according to the packet storage selection control structure. If a storage item exists in the packet storage selection control structure that has the same APID, service type, and subtype as the source packet (i.e., if the APID, service type, and subtype of the source packet exist in the packet storage selection control structure and the "storage enable flag" is "store"), then the source packet is stored; otherwise, the source packet is not stored. During storage, the storage area ID corresponding to the storage item is first obtained. Then, the onboard computer first obtains the current timecode, and stores the timecode, device source, and source packet in sequence. Based on the storage area ID in the source packet, the corresponding packet storage area is selected. The space occupied by the source packet is equal to the length represented by the source packet length type. If the effective length of the source packet is less than the occupied space, the remaining part is filled with 0x00. In this way, it is ensured that the space occupied by each source packet is of a fixed length. Therefore, for each stored data item in the packet storage area, the timecode, device source, APID, service type, subtype in the source packet, and the offset of the source packet data are all in fixed positions, which can be quickly retrieved.

[0065] The storage example is as follows: according to the storage rules, if the source packet data does not fill the 256-byte storage space, the remaining part is filled with 0x00.

[0066]

[0067] S44. Obtain and read the source package:

[0068] The source packet is obtained based on the packet storage selection control structure. The storage file corresponding to the packet storage area is located using the "Storage Area ID". The source packet's APID, business type, and subtype are used to check if the source packet exists in the packet storage area. If it exists, the source packet content is read. Specifically: based on the required source packet's APID, business type, and subtype, the packet storage selection control structure searches for storage items with the same APID, business type, and subtype. The storage area ID corresponding to this storage item is obtained. In the packet storage area corresponding to this storage area ID, a source packet with the same APID, business type, and subtype as the required source packet is searched for and read.

[0069] In addition, based on the APID, service type, and subtype of the required source packet, the storage item with the same APID, service type, and subtype can be found in the packet storage selection control structure. The storage area ID corresponding to the storage item can be obtained. In the packet storage area corresponding to the storage area ID, all source packets with timecodes within the time range can be found and read based on the device source and timecode range.

[0070] S45. Retrieve and obtain partial data from the source package:

[0071] Retrieve source package data based on content. Locate the storage file corresponding to the package storage area using the "Storage Area ID". Check if the source package exists in the package storage area based on the APID, business type, and subtype of the source package. Specifically: based on the APID, business type, and subtype of the required source package, search for storage items with the same APID, business type, and subtype in the package storage selection control structure, obtain the storage area ID corresponding to the storage item, and search for source packages with the same APID, business type, and subtype in the package storage area corresponding to the storage area ID. If found, directly retrieve the data in the source package based on the specified offset (each offset of the source package data is a fixed content).

[0072] Taking the retrieval of source packets with APID 0x1A1, service type 0x01, and subtype 0x02, and the retrieval of the star sensor temperature of that source packet (at the offset of the 57th byte of the source packet, a total of 2 bytes) as an example, the corresponding storage file is found according to the "Storage Area ID" (0x01). The storage entries with APID 0x1A1, service type 0x01, and subtype 0x02 are found to be the 1st and 4th items. The 2 bytes of data at the offset of the 57th byte of these two source packet data are obtained and used for subsequent processing.

[0073] S46. Delete source package data:

[0074] The source packet is deleted based on the packet storage selection control structure. The storage file corresponding to the packet storage area is located using the "Storage Area ID". The source packet's APID, business type, and subtype are used to check if the storage area contains the source packet, and then the source packet content is deleted. Specifically: based on the required source packet's APID, business type, and subtype, the packet storage selection control structure searches for storage items with the same APID, business type, and subtype. The storage area ID corresponding to this storage item is obtained. Within the packet storage area corresponding to this storage area ID, a source packet with the same APID, business type, and subtype as the required source packet is found and deleted.

[0075] Furthermore, based on the device origin and timecode range, all source packets with timecodes within the specified time range in the storage area can be located and their contents deleted. Alternatively, all source packet contents in the file can be deleted based on the "Storage Area ID." Specifically: based on the APID, service type, and subtype of the required source packet, the storage item with the same APID, service type, and subtype is searched in the packet storage selection control structure. The storage area ID corresponding to this storage item is obtained. Then, in the packet storage area corresponding to this storage area ID, all source packets with timecodes within the specified time range are located and deleted based on the device origin and timecode range.

[0076] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A satellite storage and retrieval method supporting packet storage and control, characterized in that: First, multiple packet storage areas with fixed-length types are established in the onboard computer; then, an Application Process Identifier (APID) control structure is set up to record storage enable flags, service types, and subtypes; next, a packet storage selection control structure is set up to record storage area IDs, source packet length types, and APID control structures; finally, operations on the source packets are implemented according to actual needs. (1) Modify storage status: By ground annotation or self-modification, the storage enable flag of APID in the packet storage selection control structure is modified to "store" or "not store", so as to modify the storage status of existing source packets and abnormal source packets; (2) Storage: For a newly received source packet, if the packet storage selection control structure contains the same APID service type and subtype as the source packet, and the "storage enable flag" is "storage", then the source packet is stored; the space not occupied by the source packet data is filled. (3) Obtain and read source packets, retrieve and obtain partial data in source packets: directly search for source packets by using the attributes set in the application process identification control structure and packet storage selection control structure, or directly obtain data in source packets by using the specified offset; (4) Deletion: When deletion is required, first locate the source package and then delete it; The APID control structure includes APID, storage enable flag, device source, service type and number of subtypes M, and M service types and subtypes; The packet storage selection control structure includes storage area ID, source packet length type, number of APIDs N, and N APID control structures.

2. The on-board storage and retrieval method as described in claim 1, characterized in that: For existing source packets, the storage status of the source packets can be modified by changing the storage enable flag of APID in the packet storage selection control structure to "store" or "not store". For abnormal source packets, the storage of abnormal source packets can be achieved by manually modifying the storage enable flag of APID in the packet storage selection control structure to "store".

3. The on-board storage and retrieval method as described in claim 1, characterized in that: The specific method for storing newly received source packets is as follows: If there is a storage item in the packet storage selection control structure that has the same APID, service type and subtype as the source packet, and the storage enable flag is "storage", then the source packet is stored. When storing, first obtain the storage area ID corresponding to the storage item, and then store the time code, device source and source packet in sequence. If the effective length of the source packet is less than the length type of the source packet in the storage area, then the part not occupied by the source packet data is filled with 0x00.

4. The on-board storage and retrieval method as described in claim 1, characterized in that: Methods for obtaining and reading the source package: Based on the APID, business type, and subtype of the required source package, search for storage items with the same APID, business type, and subtype in the package storage selection control structure, obtain the storage area ID corresponding to the storage item, and then search for the package storage area corresponding to the storage area ID: Method 1: Locate and read the source package that has the same APID, business type, and subtype as the required source package; Method 2: Based on the device source and timecode range stored when the source packet is stored, search for and read all source packets in the packet storage area that belong to the device source or whose timecode is within the time range.

5. The on-board storage and retrieval method as described in claim 1, characterized in that: Retrieve and obtain partial data from the source package: Based on the APID, business type, and subtype of the required source packet, search for a storage item with the same APID, business type, and subtype in the packet storage selection control structure, obtain the storage area ID corresponding to the storage item, and search for a source packet with the same APID, business type, and subtype as the required source packet in the packet storage area corresponding to the storage area ID. Based on the specified offset, directly obtain the data in the source packet.

6. The on-board storage and retrieval method as described in claim 1, characterized in that: Methods to delete the source package: Based on the APID, business type, and subtype of the required source package, search for storage items with the same APID, business type, and subtype in the package storage selection control structure, obtain the storage area ID corresponding to the storage item, and then search for the package storage area corresponding to the storage area ID: Method 1: Find and delete the source package that has the same APID, business type, and subtype as the required source package; Method 2: Based on the device source and timecode range stored when the source packet is required, find all source packets in the packet storage area that belong to the device source or whose timecodes are within the time range, and delete them.

7. The on-board storage and retrieval method as described in claim 1, characterized in that: The source packet length can be 64 bytes, 128 bytes, 256 bytes, 512 bytes, 1024 bytes, 2048 bytes, 4096 bytes, 8192 bytes, or 16384 bytes, or extended to the corresponding number of bytes as required.

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