A telemetry downlink method for autonomous payload scheduling

Abstract

This invention relates to a telemetry downlink method for autonomous payload scheduling, comprising the following steps: The satellite management software collects current telemetry data via a telemetry acquisition module, serial port, and bus, and caches it in memory; based on the collected telemetry data, it determines whether the satellite is currently in a safe mode; the satellite management system schedules the frame-by-frame downlink of each telemetry packet according to this scheduling table; based on the results of ground mission planning or autonomous mission planning, it determines whether to begin service operation; if the time has not yet arrived, the satellite management system schedules the frame-by-frame downlink of each telemetry packet according to the telemetry scheduling table of the steady-state operation mode; based on the results of ground mission planning or autonomous mission planning, it determines whether to begin service operation; if the time has arrived, the satellite management system adjusts the downlink cycle of telemetry packets for each platform; the payload management software generates two telemetry packets; after the satellite management software assembles the telemetry frames, it transmits them to the ground via a transponder; the ground telemetry parsing software parses the content of different telemetry packets according to different APIDs.

Description

Technical Field

[0001] This invention relates to the field of spacecraft technology, and more specifically, to a telemetry downlink method for autonomous payload scheduling. Background Technology

[0002] With the rapid development of my country's aerospace industry, the complexity of spacecraft platforms and payloads is increasing, and the required telemetry resources to characterize their status are also growing. However, the downlink code rate commonly used for spacecraft transit is only 8192bps or 16384bps, which is insufficient to meet the requirement of transmitting as much telemetry data as possible within a specified time.

[0003] For example, Chinese patent document CN106688332B discloses an implementation scheme for centralized allocation and scheduling of satellite telemetry. By updating all telemetry parameters of the satellite at regular intervals and considering the length of each data packet, it can achieve the ability to transmit any number of telemetry parameters at the fastest rate within a certain period of time. However, this method changes the way of telemetry transmission rate by on-orbit programming, which is not convenient for actual use.

[0004] Chinese patent document CN105450545A discloses an adaptive dynamic telemetry packet scheduling method. This method achieves flexible switching of the telemetry packet downlink cycle by autonomously replacing the telemetry packet scheduling table or adjusting the number of notes in the telemetry table parameters in conjunction with the telemetry packet scheduling algorithm. However, this method can cause the downlink cycle of some telemetry packets to become too long, resulting in inconvenience for ground judgment.

[0005] The preceding description is intended to provide general background information and does not necessarily constitute prior art. Summary of the Invention

[0006] The purpose of this invention is to provide a telemetry downlink method for autonomous payload scheduling, which improves ground personnel's understanding of satellite status and meets the application requirements of satellite on-orbit telemetry.

[0007] This invention provides a telemetry downlink method for autonomous payload scheduling, the method comprising the following steps:

[0008] S1: The satellite management software collects the telemetry data captured during the current shooting through the telemetry acquisition module, serial port, and bus, and caches it in the memory area;

[0009] S2: The satellite management software determines whether the satellite is in safe mode based on the collected telemetry data. If it is in safe mode, it automatically switches to the telemetry scheduling table of steady-state operation mode. The satellite management then schedules the downlink of each telemetry packet group according to this scheduling table.

[0010] S3: If not in safe mode, the satellite service software determines whether to start service operation based on the results of ground mission planning or autonomous mission planning. If the time has not arrived, the satellite service schedules the downlink of each telemetry packet group according to the telemetry scheduling table of steady-state operation mode.

[0011] S4: The space service software determines whether to start operational services based on the results of ground mission planning or autonomous mission planning. If the time is up, the space service software adjusts the downlink cycle of telemetry packets for each platform. The adjusted cycle must meet the following condition: [(number of 1-byte platform packet / downlink cycle in operational mode) + (number of 2-byte platform packet / downlink cycle in operational mode) + ... + (number of 1-byte payload packet / downlink cycle) + (number of 2-byte payload packet / downlink cycle)] ≤ [(number of 1-byte platform packet / downlink cycle in steady-state mode) + (number of 2-byte platform packet / downlink cycle in steady-state mode) + ... + (number of 1-byte platform packet / downlink cycle in steady-state mode)];

[0012] S5: The payload management software generates two telemetry packets, which are transmitted to the satellite management software via bus or serial port.

[0013] S6: The satellite management software retrieves two telemetry packets from the bus or serial port. The first telemetry packet is placed into the telemetry frame by the satellite management software after the downlink cycle. After the second telemetry packet is placed into the downlink cycle, the satellite management software determines whether the APID area to be modified in the last 2 bytes of the telemetry packet header is consistent with the APID in the telemetry packet header. If they are consistent, the packet is placed directly into the telemetry frame. If they are inconsistent, the APID in the telemetry packet header is replaced and the packet is placed into the telemetry frame that the satellite management needs to downlink in the current cycle.

[0014] S7: After the satellite communication software assembles the telemetry frames, it transmits them to the ground via the transponder. The ground telemetry analysis software then parses the contents of different telemetry packets according to different APIDs.

[0015] Furthermore, in step S5, the two telemetry packets are telemetry packet 1 and telemetry packet 2, respectively. Telemetry packet 1 is formed by telemetry shared by various service modes of payload collection. Telemetry packet 2 is formed by telemetry specific to each service mode of payload. The telemetry packets 2 formed under different modes need to have the same byte length, and any extra space is fixedly filled with 0xAA. The 2 bytes after the header of telemetry packet 2 are used as the actual APID of the packet.

[0016] Furthermore, step S2 also includes the satellite software extracting battery voltage and attitude control anomaly request telemetry information from the collected telemetry data. If the battery voltage is lower than the threshold or the attitude control anomaly flag is set to anomaly, it is determined that the system is in a safe mode.

[0017] Furthermore, the serial port is an RS422 serial port or an LVDS serial port, and the bus is a CAN bus or a 1553B bus.

[0018] Furthermore, the APID is a telemetry packet identifier.

[0019] The payload autonomous scheduling telemetry downlink method of the present invention, which involves the payload autonomously scheduling telemetry packets and the satellite service software cooperating with the frame assembly processing method, can effectively solve the problem of invalid data occupying limited downlink bandwidth under different working modes of the payload. By scheduling only valid information for downlink, it achieves the effect of more downlink telemetry data. The satellite service software cooperating with the frame assembly processing method can effectively solve the problem that the satellite service software also needs to adjust the telemetry frame structure due to the need for the payload software to increase the number of telemetry packets, thus providing a certain degree of convenience for use. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the telemetry downlink method for autonomous payload scheduling provided in an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of telemetry frames under different modes provided in the embodiments of the present invention. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0023] The terms "first," "second," "third," "fourth," etc., used in the specification and claims of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. Example

[0024] Figure 1 This is a flowchart illustrating the telemetry downlink method for autonomous payload scheduling provided in an embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the structure of telemetry frames under different modes provided in embodiments of the present invention. Please refer to... Figure 1 , Figure 2 The telemetry downlink method for autonomous payload scheduling provided in this embodiment of the invention includes the following steps:

[0025] S1: The satellite management software collects the telemetry data captured during the current period through the telemetry acquisition module, serial port, and bus, and caches it in the memory area; specifically, the serial port is an RS422 serial port or an LVDS serial port, and the bus is a CAN bus or a 1553B bus.

[0026] S2: The satellite management software determines whether the satellite is in safe mode based on the collected telemetry data. If it is in safe mode, it automatically switches to the telemetry scheduling table of steady-state operation mode (under this scheduling table, the downlink frequency of each telemetry packet on the platform is increased, and the downlink frequency of the telemetry packet can be changed by registering numbers). The satellite management system schedules the frame-based downlink of each telemetry packet according to this scheduling table. Specifically, the satellite management software extracts telemetry information such as battery voltage and attitude control anomaly requests from the collected telemetry data. If the battery voltage is lower than the threshold or the attitude control anomaly flag is set to anomaly, it is determined that the satellite is in safe mode.

[0027] S3: If not in safe mode, the satellite service software determines whether to start service operation based on the results of ground mission planning or autonomous mission planning. If the time has not arrived, the satellite service schedules the downlink of each telemetry packet group according to the telemetry scheduling table of steady-state operation mode.

[0028] S4: If not in safe mode, the space service software determines whether to start operational service based on ground mission planning or autonomous mission planning results. If the time is up, the space service software adjusts the downlink cycle of telemetry packets for each platform. The adjusted cycle must satisfy [(1 byte of platform packet in operational mode / downlink cycle) + (2 bytes of platform packet in operational mode / downlink cycle) + ... + (1 byte of payload packet / downlink cycle) + (2 bytes of payload packet / downlink cycle)] ≤ [(1 byte of platform packet in steady-state mode / downlink cycle) + (2 bytes of platform packet in steady-state mode / downlink cycle) + ... + (2 bytes of platform packet in steady-state mode / downlink cycle)]. A fixed area is left empty in the telemetry frame as the payload fixed area, such as... Figure 2 As shown;

[0029] S5: The payload management software generates two telemetry packets, which are transmitted to the satellite management software via bus or serial port.

[0030] Specifically, the two telemetry packets are telemetry packet 1 and telemetry packet 2; assume that the APID of telemetry packet 1 is 0x500 and the APID of telemetry packet 2 is 0x501; APID is the telemetry packet identifier.

[0031] Telemetry packet 1 is formed by collecting telemetry data shared by various service modes of the payload, including the voltage and current of each individual payload unit, the payload operating mode, etc. Telemetry packet 2 is formed by telemetry data specific to each service mode of the payload. Telemetry packets 2 formed under different modes must have the same byte length, with extra space filled with 0xAA. The two bytes after the header of telemetry packet 2 are used as the actual APID of the packet. Specifically, assuming 0x510 is payload operating mode 1, 0x511 is payload operating mode 2, 0x512 is payload operating mode 3, etc., subsequent payloads can be continuously added through on-orbit programming and transmitted to the space service software via bus or serial port.

[0032] S6: The satellite management software retrieves two telemetry packets from the bus or serial port. The first telemetry packet is placed into the telemetry frame by the satellite management software after the downlink cycle. After the second telemetry packet is placed into the downlink cycle, the satellite management software determines whether the APID area to be modified in the last 2 bytes of the telemetry packet header is consistent with the APID in the telemetry packet header. If they are consistent, the packet is placed directly into the telemetry frame. If they are inconsistent, the APID in the telemetry packet header is replaced and the packet is placed into the telemetry frame that the satellite management needs to downlink in the current cycle.

[0033] Specifically, the satellite communication software first identifies the APID (APID) from fixed-length data received from the bus or serial port. Based on the telemetry packet information configured in the software, it locates two telemetry packets, 0x500 and 0x501. 0x500 is used as the first payload packet and is placed into the telemetry frame by the satellite communication software during the next transmission cycle. 0x501 is used as the second payload packet. During the next transmission cycle, the satellite communication software checks whether the APID to be modified in the last two bytes of the telemetry packet header matches the APID in the telemetry packet header. If they match, the APID is placed directly into the telemetry frame. If they do not match, the APID in the telemetry packet header is replaced and then placed into the telemetry frame that the satellite communication software needs to transmit in the current cycle.

[0034] S7: After the satellite communication software assembles the telemetry frames, it transmits them to the ground via the transponder. The ground telemetry analysis software then parses the contents of different telemetry packets according to different APIDs.

[0035] As can be seen from the above description, the advantages of this invention are:

[0036] 1. The payload autonomous scheduling telemetry downlink method of the present invention, which uses payload autonomous scheduling of telemetry packets and satellite software in conjunction with frame processing, can effectively solve the problem of invalid data occupying limited downlink bandwidth under different working modes of the payload. By scheduling only valid information for downlink, it achieves the effect of more downlink telemetry data.

[0037] 2. The telemetry downlink method for autonomous payload scheduling of the present invention, which involves autonomously scheduling telemetry packets by the payload and coordinating frame processing with the satellite service software, can effectively solve the problem that the satellite service software also needs to adjust the telemetry frame structure due to the need for the payload software to increase the number of telemetry packets, thus providing certain convenience for use.

[0038] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A telemetry downlink method for autonomous payload scheduling, characterized in that, The method includes the following steps: S1: The satellite management software collects the telemetry data captured during the current shooting through the telemetry acquisition module, serial port, and bus, and caches it in the memory area; S2: The satellite management software determines whether the satellite is in safe mode based on the collected telemetry data. If it is in safe mode, it automatically switches to the telemetry scheduling table of steady-state operation mode. The satellite management then schedules the downlink of each telemetry packet group according to this scheduling table. S3: If not in safe mode, the satellite service software determines whether to start service operation based on the results of ground mission planning or autonomous mission planning. If the time has not arrived, the satellite service schedules the downlink of each telemetry packet group according to the telemetry scheduling table of steady-state operation mode. S4: The satellite software determines whether to start operational services based on the results of ground mission planning or autonomous mission planning. If the time is up, the satellite software adjusts the download cycle of telemetry packets for each platform. S5: The payload management software generates two telemetry packets, which are transmitted to the satellite management software via bus or serial port. S6: The satellite management software retrieves two telemetry packets from the bus or serial port. The first telemetry packet is placed into the telemetry frame by the satellite management software after the downlink cycle. After the second telemetry packet is placed into the downlink cycle, the satellite management software determines whether the 2-byte APID area to be modified after the telemetry packet header is consistent with the APID in the telemetry packet header. If they are consistent, the packet is placed directly into the telemetry frame. If they are inconsistent, the APID in the telemetry packet header is replaced and the packet is placed into the telemetry frame that needs to be downlinked in the current cycle. S7: After the satellite communication software assembles the telemetry frames, it transmits them to the ground via the transponder. The ground telemetry analysis software then parses the contents of different telemetry packets according to different APIDs.

2. The telemetry downlink method for autonomous payload scheduling according to claim 1, characterized in that, In step S5, the two telemetry packets are telemetry packet 1 and telemetry packet 2. Telemetry packet 1 is formed by telemetry shared by various service modes of payload collection. Telemetry packet 2 is formed by telemetry unique to each service mode of payload. The telemetry packets 2 formed under different modes need to have the same byte length, and the extra parts are fixedly filled with 0xAA. The 2 bytes after the header of telemetry packet 2 are used as the actual APID of the packet.

3. The telemetry downlink method for autonomous payload scheduling according to claim 1, characterized in that, Step S2 further includes the satellite software extracting battery voltage and attitude control anomaly request telemetry information from the collected telemetry data. If the battery voltage is lower than the threshold or the attitude control anomaly flag is set to anomaly, it is determined that the system is in a safe mode.

4. The telemetry downlink method for autonomous payload scheduling according to claim 1, characterized in that, The serial port is an RS422 serial port or an LVDS serial port, and the bus is a CAN bus or a 1553B bus.

5. The telemetry downlink method for autonomous payload scheduling according to claim 1, characterized in that, APID stands for Telemetry Packet Identifier.

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