On-orbit autonomous playback method and system for segmental downlink of satellite-stored data

Abstract

The present invention provides an on-board autonomous playback method and system for segment-based downlink of satellite-stored data, including: time period information for segment-based playback of data in the ground upload memory; performing control of selective point playback and resume from breakpoint. The present invention features on-board autonomous calculation and continuous and non-lossy segment-based playback of data, realizes segment-based playback of satellite-stored data according to time periods, and meets the function of continuous reception of segment-based data by multiple ground stations of the satellite.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite on-board software, and particularly to an on-board autonomous playback method and system for segment selection and downlink of satellite stored data. Background Art

[0002] In the method of autonomous transmission and playback of satellite data transmission data to the ground station, generally, the stored data is downlinked and played back in a sequential playback manner. Relying on the on-board program control software, according to the playback requirements and criterion conditions, it autonomously judges to turn on and off the data transmission device and perform playback operations. The advantage of this method is that it realizes the uninterrupted sequential reading of the data on the satellite memory, and the whole process is autonomously realized without ground intervention. However, for the task of segment selection and playback of a certain period of data stored on the satellite, which has special data playback requirements, it cannot effectively meet the requirements.

[0003] After retrieving the prior art:

[0004] Patent document CN108847880A realizes the uninterrupted sequential reading of the data on the satellite memory, which is suitable for reading and playing back the data stored in the satellite memory in chronological order, and does not have the function of selecting data for downlink playback according to time segments.

[0005] Patent document CN1481132A discloses a large file multicast distribution method for a satellite data broadcast system, which belongs to the method of file data delivery on a one-way unreliable link of a satellite.

[0006] Patent document CN103873134A realizes a satellite data subscription method compatible with multiple data formats, and solves the universality, scalability and user data customization of different satellite test data formats presented on different platforms.

[0007] Patent document CN103076990A discloses a data playback device based on a FIFO cache structure, which belongs to the technical field of analog output.

[0008] Patent document CN107766440A belongs to the field of satellite testing, and is used for receiving, storing and extracting various satellite test data.

[0009] The above prior arts cannot solve the technical problem of selecting data for downlink playback according to time segments. Summary of the Invention

[0010] Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide an on-board autonomous playback method and system for segment selection and downlink of satellite stored data.

[0011] An on-board autonomous playback method for segment selection and downlink of satellite stored data according to the present invention includes:

[0012] Step SA: Inject the time code information for segment playback of the memory data on the ground. The time code information includes the start time and end time of data storage. The memory read pointer can retrieve and access the data according to the start time and end time.

[0013] Step SB: Perform control of selective point playback and resume from breakpoint according to the time code information.

[0014] Preferably, the step SB includes:

[0015] Step SB.1: Calculate the positioning information of the satellite in the WGS-84 geocentric coordinate system at time t, and assign 0 to the number n of ground stations that meet the elevation requirement. Traverse all num ground stations, and calculate the elevation angle hw(j) of the satellite relative to the jth ground station. If hw(j) is greater than the preset elevation angle Asta(j) of the jth ground station, then increment n by 1, otherwise, n remains unchanged.

[0016] Step SB.2: When the number n of ground stations that meet the elevation requirement is greater than 0, turn on the data transmission transmitter and set the power-on flag KJ to 1. If the data transmission memory read send flag STR = 0, then determine whether the selective point read instruction of the memory has been sent. When the selective point read send flag TCR of the memory = 0, perform the selective point read operation of the memory and set the selective point read send flag TCR and the memory read send flag STR to 1. When the selective point read send flag TCR of the memory = 1, then perform the resume from breakpoint operation of the memory and set the memory read send flag STR to 1.

[0017] Step SB.3: When the count n of ground stations with elevation meeting the requirement is not greater than 0, determine whether there is a read overflow through memory telemetry. If there is a read overflow in the memory, it indicates that all data has been read in segments, and assign the selective point read send flag TCR of the memory = 0. When the data transmission memory read send flag STR = 1, perform the memory read stop operation and assign STR = 0. If the data transmission transmitter power-on flag KJ = 1, then perform the single-unit shutdown operation of the data transmission transmitter and assign the data transmission power-on flag KJ = 0.

[0018] Preferably, in the step SB, the selective point read instruction and the resume from breakpoint instruction of the memory contain the time code information injected on the ground, and the read pointer is retrieved and played back according to the time code information.

[0019] Preferably, the memory data read pointer and the data write pointer are independent of each other, and data writing is performed in parallel while retrieving and playing back the data. The resume from breakpoint operation cannot be sent alone and needs to cooperate with the selective point read. The resume from breakpoint continues to transmit the subsequent time segments starting from the position where the previous selective point read stopped. When the memory data read pointer approaches or is equal to the preset distance of the write pointer, a memory read overflow will be triggered.

[0020] Preferably, the preset elevation angle Asta(j) is set by the number of ground uploads.

[0021] A on-satellite autonomous playback system for satellite stored data segment download according to the present invention includes:

[0022] Module MA: The time code information for segment playback of the data in the ground upload memory, where the time code information includes the start time and end time of data storage, and the memory read pointer can retrieve and access the data according to the start time and end time.

[0023] Module MB: According to the time code information, perform pick-point playback and breakpoint resume control.

[0024] Preferably, the module MB includes:

[0025] Module MB.1: Calculate the positioning information of the satellite in the WGS-84 geocentric coordinate system at time t, and assign 0 to the number n of ground stations that meet the elevation angle requirement; traverse all num ground stations, and calculate the elevation angle hw(j) of the satellite relative to the jth ground station at time t; if hw(j) is greater than the jth preset elevation angle Asta(j), then increment n by 1, otherwise, n remains unchanged.

[0026] Module MB.2: When the number n of ground stations that meet the elevation angle requirement is greater than 0, turn on the data transmission transmitter and set the power-on flag KJ to 1; if the data transmission memory read send flag STR = 0, then determine whether the memory pick-point read instruction has been sent. When the memory pick-point read send flag TCR = 0, perform the memory pick-point read operation and set the memory pick-point read send flag TCR and the memory read send flag STR to 1; when the memory pick-point read send flag TCR = 1, then perform the memory breakpoint resume operation and set the memory read send flag STR to 1.

[0027] Module MB.3: When the count n of ground stations with the elevation angle meeting the requirement is not greater than 0, determine whether there is a read overflow through memory telemetry. If there is a read overflow in the memory, it indicates that all data has been segmentally read out, and assign the memory pick-point read send flag TCR = 0; when the data transmission memory read send flag STR = 1, perform the memory read stop operation and assign STR = 0; if the data transmission transmitter power-on flag KJ = 1, then perform the single-unit shutdown operation of the data transmission transmitter and assign the data transmission power-on flag KJ = 0.

[0028] Preferably, in the module MB, the memory pick-point read and memory breakpoint resume instructions contain the time code information of the ground upload, and the read pointer is retrieved and played back according to the time code information.

[0029] Preferably, the memory data read pointer and the data write pointer are independent of each other, and data writing is performed in parallel while retrieving and playing back data; the breakpoint continuation operation cannot be sent alone and needs to be combined with selective reading. The breakpoint continuation starts from the position where the previous selective reading stopped and continues to transmit the subsequent time period; when the memory data read pointer approaches or is equal to the preset distance of the write pointer, a memory read overflow will be triggered.

[0030] Preferably, the preset elevation angle Asta(j) is set by the number of ground injections.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention solves the problem of playing back on-board stored data by time period.

[0033] 2. The present invention has the characteristics of on-board autonomous calculation and continuous non-loss of selectively played-back data. There will be no discontinuity between data selective reading and breakpoint continuation due to the switching of ground stations, meeting the function of continuous reception of selectively segmented data by multiple ground stations of the satellite. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] By reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent:

[0035] Figure 1 It is a schematic diagram of the main process of autonomous playback of selectively segmented downlink of satellite stored data according to the present invention.

[0036] Figure 2 It is a schematic diagram of the control process of data selective playback and breakpoint continuation according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0038] As Figure 1 shown, a method for on-board autonomous playback of selectively segmented downlink of satellite stored data according to the present invention includes the following steps:

[0039] Step S1, injecting the time code information of selectively segmented playback of memory data on the ground. The time code information includes the start time and end time of data storage, and the memory read pointer can retrieve and access data according to the start time and end time;

[0040] Step S2: Determine whether on - satellite data transmission playback program control is allowed; determine whether data transmission program control is allowed according to the flag that can be modified by ground uploading. If allowed, execute the subsequent steps; otherwise, skip the subsequent steps.

[0041] Step S3: Perform selective point playback and breakpoint - continued transmission control.

[0042] The present invention will be described in more detail below.

[0043] As Figure 2 shown, the data selective point playback and breakpoint - continued transmission control process is as follows:

[0044] First, calculate the positioning information of the satellite at time t (WGS - 84 geocentric coordinate system), assign 0 to the count n of ground stations that meet the elevation angle requirement, calculate the elevation angle of the satellite relative to the ground station at time t. When the elevation angle hw(j) of the satellite relative to the j - th ground station at time t is greater than the preset elevation angle Asta(j), increment the count n of ground stations that meet the elevation angle requirement at the current time by 1; otherwise, skip the counting operation of this ground station, where the j - th ground station traverses all num ground stations.

[0045] Step S3a: When the count n of ground stations that meet the elevation angle requirement is greater than 0, execute the following process:

[0046] Determine whether the data transmission transmitter is in the on - state. If KJ = 0, perform the operation of turning on the data transmission transmitter, and set the transmitter on - state flag KJ to 1; otherwise, skip this operation and proceed to the next step.

[0047] When the data transmission memory read - send flag STR = 0, execute the following process; otherwise, skip this operation:

[0048] Determine whether the memory selective point read instruction has been sent. When the memory selective point read - send flag TCR = 0, perform the memory selective point read operation and set both the memory selective point read - send flag TCR and the memory read - send flag STR to 1; when the memory selective point read - send flag TCR = 1, perform the memory breakpoint - continued transmission operation and set the memory read - send flag STR to 1.

[0049] Step S3b: When the count n of ground stations with the elevation angle meeting the requirement is not greater than 0, execute the following process:

[0050] First, determine whether the read - out overflow has occurred through memory telemetry. If the memory has read - out overflow, it indicates that all data has been selectively read in segments, and assign the memory selective point read - send flag TCR = 0; otherwise, skip this operation.

[0051] When the data transmission memory read - send flag STR = 1, perform the memory read - stop operation and assign STR = 0; otherwise, skip this operation and proceed to the next step.

[0052] If the data transmission transmitter power-on flag KJ = 1, perform the single-unit shutdown operation of the data transmission transmitter and assign the data transmission power-on flag KJ = 0; otherwise, skip this operation.

[0053] The present invention will be described in more detail below in conjunction with preferred examples.

[0054] The preset elevation angle Asta(j) in step S3 can be flexibly set through ground data injection. The memory pickpoint read and memory breakpoint resume transmission instructions contain the time code information injected from the ground, and the read pointer is retrieved and played back according to the time code information. The memory data read pointer and the data write pointer can be completely independent, and data can be written while retrieving and playing back the data. The breakpoint resume transmission operation cannot be sent alone and needs to be coordinated with pickpoint read. The breakpoint resume transmission continues to transmit the subsequent time period from the position where the previous pickpoint read stopped. When the memory data read pointer approaches or is equal to the write pointer, a memory read overflow will be triggered.

[0055] The present invention also provides an on-board autonomous playback system for satellite stored data segment-by-segment downlink. Those skilled in the art can implement the on-board autonomous playback system for satellite stored data segment-by-segment downlink by executing the process steps of the on-board autonomous playback method for satellite stored data segment-by-segment downlink. That is, the on-board autonomous playback method for satellite stored data segment-by-segment downlink can be understood as the preferred implementation manner of the on-board autonomous playback system for satellite stored data segment-by-segment downlink. Specifically, an on-board autonomous playback system for satellite stored data segment-by-segment downlink provided by the present invention includes:

[0056] Module MA: Inject the time code information of the memory data segment-by-segment playback from the ground. The time code information includes the start time and end time of data storage, and the memory read pointer can retrieve and access the data according to the start time and end time;

[0057] Module MB: Control pickpoint playback and breakpoint resume transmission according to the time code information.

[0058] Those skilled in the art know that in addition to implementing the systems, devices, and their respective modules provided by the present invention in the form of pure computer-readable program codes, the method steps can be logically programmed to enable the systems, devices, and their respective modules provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers, etc., to implement the same program. Therefore, the systems, devices, and their respective modules provided by the present invention can be regarded as a kind of hardware component, and the modules included therein for implementing various programs can also be regarded as the structures within the hardware component; the modules for implementing various functions can also be regarded as both software programs for implementing the method and the structures within the hardware component.

[0059] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An on-board autonomous playback method for segment-based downlink of satellite stored data, characterized in that, it includes: Step SA: Inject the time code information for segment-based playback of the memory data on the ground. The time code information includes the start time and end time of data storage. The memory read pointer can retrieve and access the data according to the start time and end time; Step SB: Perform control of selective playback and resume from breakpoint according to the time code information; The said Step SB includes: Step SB.1: Calculate the positioning information of the satellite in the WGS-84 geocentric coordinate system at time t, and assign the number n of ground stations that meet the elevation requirement to 0; Traverse all num ground stations, and calculate the elevation angle hw(j) of the satellite relative to the j-th ground station at time t; If hw(j) is greater than the preset elevation angle Asta(j) of the j-th ground station, then increment n by 1, otherwise, n remains unchanged; Step SB.2: When the number n of ground stations that meet the elevation requirement is greater than 0, turn on the data transmission transmitter and set the data transmission transmitter on flag KJ to 1; If the data transmission memory read send flag STR = 0, then determine whether the selective read instruction of the memory has been sent. When the selective read send flag TCR of the memory = 0, perform the selective read operation of the memory and set the selective read send flag TCR and the memory read send flag STR to 1; When the selective read send flag TCR of the memory = 1, then perform the resume from breakpoint operation of the memory and set the memory read send flag STR to 1; Step SB.3: When the count n of ground stations with elevation angle meeting the requirement is not greater than 0, determine whether there is a read overflow through memory telemetry. If there is a read overflow in the memory, it indicates that all data has been read in segments, and assign the selective read send flag TCR of the memory = 0; When the data transmission memory read send flag STR = 1, perform the memory read stop operation and assign STR = 0; If the data transmission transmitter on flag KJ = 1, then perform the single-unit shutdown operation of the data transmission transmitter and assign the data transmission transmitter on flag KJ = 0; In the said Step SB, the selective read instruction and the resume from breakpoint instruction of the memory contain the time code information injected on the ground, and the read pointer is retrieved and played back according to the time code information.

2. The on-board autonomous playback method for segment-based downlink of satellite stored data according to claim 1, characterized in that, The memory data read pointer and the data write pointer are independent of each other, and data writing is performed in parallel while retrieving and playing back the data; The resume from breakpoint operation cannot be sent alone and needs to be coordinated with the selective read. The resume from breakpoint continues to transmit the subsequent segment from the position where the previous selective read stopped; When the memory data read pointer approaches or is equal to the preset distance of the write pointer, a memory read overflow will be triggered.

3. The on-board autonomous playback method for segment-based downlink of satellite stored data according to claim 1, characterized in that, The said preset elevation angle Asta(j) is set by injecting data on the ground.

4. An on-board autonomous playback system for segment-based downlink of satellite stored data, characterized in that, it includes: Module MA: The time code information for segment playback of the data stored in the ground upload memory. The time code information includes the start time and the end time of data storage. The memory read pointer can retrieve and access the data according to the start time and the end time; Module MB: Control the selective playback and resume-from-breakpoint transmission according to the time code information; The said Module MB includes: Module MB.1: Calculate the positioning information of the satellite in the WGS-84 geocentric coordinate system at time t, and assign 0 to the number n of ground stations that meet the elevation angle requirement. Traverse all num ground stations, and calculate the elevation angle hw(j) of the satellite relative to the j-th ground station at time t. If hw(j) is greater than the preset elevation angle Asta(j) of the j-th ground station, then increment n by 1, otherwise, n remains unchanged; Module MB.2: When the number n of ground stations that meet the elevation angle requirement is greater than 0, turn on the data transmission transmitter and set the data transmission transmitter turn-on flag KJ to 1. If the data transmission memory read send flag STR = 0, then determine whether the selective read instruction of the memory has been sent. When the selective read send flag TCR of the memory = 0, perform the selective read operation of the memory and set the selective read send flag TCR and the memory read send flag STR to 1. When the selective read send flag TCR of the memory = 1, then perform the resume-from-breakpoint transmission operation of the memory and set the memory read send flag STR to 1; Module MB.3: When the count n of ground stations with the elevation angle meeting the requirement is not greater than 0, determine whether there is a read overflow through memory telemetry. If there is a read overflow in the memory, it indicates that all the data has been selectively read out in segments, and assign the selective read send flag TCR of the memory = 0. When the data transmission memory read send flag STR = 1, perform the memory read stop operation and assign STR = 0. If the data transmission transmitter turn-on flag KJ = 1, then perform the single-unit turn-off operation of the data transmission transmitter and assign the data transmission transmitter turn-on flag KJ = 0; In the said Module MB, the selective read instruction and the resume-from-breakpoint transmission instruction of the memory contain the time code information of the ground upload, and the read pointer is retrieved and played back according to the time code information.

5. The on-board autonomous playback system for satellite storage data segment download according to claim 4, characterized in that The memory data read pointer and the data write pointer are independent of each other, and while retrieving and playing back the data, the data is written in parallel; The resume-from-breakpoint transmission operation cannot be sent alone and needs to cooperate with the selective read. The resume-from-breakpoint transmission starts from the position where the previous selective read stopped and continues to transmit the subsequent time segment; When the memory data read pointer is close to or equal to the preset distance of the write pointer, a memory read overflow will be triggered.

6. The on-board autonomous playback system for satellite storage data segment download according to claim 4, characterized in that The said preset elevation angle Asta(j) is set by ground injection data.

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