A laser and vdes on-orbit data processing system

Abstract

The application provides a laser and VDES on-orbit data processing system, comprising: a laser payload data processing unit for receiving data of a laser payload, real-time forwarding laser intersatellite data to original data to a VDES payload, and sending laser service data to an on-orbit data storage management unit; a VDES payload data processing unit for receiving data of a VDES payload, real-time forwarding intersatellite data to a transmission frame to a laser payload, and sending VDES service data to the on-orbit data storage management unit; an S-band transceiving network unit for sending on-orbit data playback framing to a ground station and receiving ground station data to forward to a corresponding payload; an on-orbit data storage management unit for storage management and supporting on-orbit adjustment of storage partition size; and a satellite computer data processing unit for executing remote control instructions and feeding back system status, receiving engineering parameters and sending to the on-orbit data storage management unit.

Description

Technical Field

[0001] This invention belongs to the field of spaceborne data processing, and in particular relates to an on-orbit data processing system for laser and VDES. Background Technology

[0002] The Automatic Identification System (AIS) is the core of maritime ship-to-ship and ship-to-shore data communication. The VHF Data Exchange System (VDES) is an enhanced and upgraded version of the AIS. In addition to integrating all the functions of the existing AIS, it adds special application messages and broadband VHF data exchange capabilities to support two-way data communication between ships and shore stations, and between ships themselves. It also expands its broadcasting capabilities and provides dedicated information channels for weather and navigation, which is of great significance for promoting the development of the maritime radio digital communication industry.

[0003] The laser and VDES on-orbit data processing system is a crucial component of the VDES technology verification satellite. Its main tasks include: managing data exchange and storage between the onboard VDES payload, laser payload, and satellite-based computer; establishing a satellite-to-ground uplink to receive and demodulate S-band uplink data signals from the S-band transceiver network; and simultaneously establishing a downlink to transmit and modulate downlink data signals, converting them to S-band for output to the S-band transceiver network, which then outputs them to the QV transceiver for downlink data transmission after satellite arrival. Summary of the Invention

[0004] To address the shortcomings of existing on-board data storage devices, such as the lack of real-time mutual forwarding of data between internal satellite payloads, the lack of ability to simultaneously establish data exchange between laser payloads, VDES payloads, and satellite-to-ground links, and the lack of data interaction between different satellites in a satellite constellation, this invention aims to overcome these deficiencies and proposes an on-orbit data processing system for lasers and VDES.

[0005] To achieve the above objectives, this invention proposes an on-orbit data processing system for laser and VDES payloads. The system includes: a laser payload data processing unit, a VDES payload data processing unit, an S-band transceiver network unit, an on-board data storage management unit, and a satellite-based computer data processing unit.

[0006] The laser payload data processing unit is used to receive data from the laser payload, perform serial-to-parallel conversion and format detection. For inter-satellite laser data, it restores the original data according to the protocol and forwards it to the VDES payload in real time. For laser service data, it sends it to the on-board data storage management unit for storage management.

[0007] The VDES payload data processing unit is used to receive VDES payload data, perform serial-to-parallel conversion and format detection. For inter-satellite data, it organizes transmission frames according to the protocol and forwards them to the laser payload in real time. For VDES service data, it sends them to the on-board data storage management unit for storage management.

[0008] The S-band transceiver network unit is used to establish downlink and uplink links with the ground station, to send on-board data playback frames to the ground station, and to receive data from the ground station and forward it to the corresponding payload according to the protocol.

[0009] The on-board data storage management unit is used to complete the storage management of different types of data on the satellite and supports on-orbit adjustment of storage partition size;

[0010] The satellite computer data processing unit is used to execute remote control commands from the satellite computer, perform on-orbit tasks, and report the system status back to the satellite computer. It is also used to receive engineering parameters from the satellite computer and send them to the on-board data storage management unit to complete on-orbit data storage management.

[0011] Preferably, the laser payload includes more than one unit, using a cold standby mode, supporting only one laser payload to work independently in orbit at a time; the VDES payload includes one or more units, using a hot standby mode, supporting one VDES payload to work independently in orbit or two VDES payloads to work simultaneously in orbit at a time.

[0012] Preferably, the processing procedure of the laser payload data processing unit includes:

[0013] The received laser payload data is converted from serial to parallel and its format is checked. If bytes B0 to B3 are 0xFAF32000, the data is valid; otherwise, it is invalid.

[0014] For valid data, further determination is made: if B4 to B5 are 0x47F8, it is laser inter-satellite data, which is restored to the original data according to the protocol and forwarded to the VDES payload in real time; otherwise, it is laser service data, which is sent to the laser storage area of ​​the onboard data storage management unit for storage management.

[0015] Preferably, the interface of the laser payload data processing unit adopts a three-wire LVDS, and the clock frequency for both receiving and transmitting is 60MHz.

[0016] Preferably, the processing procedure of the VDES payload data processing unit includes:

[0017] The received VDES payload data undergoes serial-to-parallel conversion and format detection. If bytes B0 to B1 are 0xEB90 or 0xEB9A, the data is valid; otherwise, it is invalid. Among them, 0xEB9A is VDES inter-satellite data, which is organized into transmission frames according to the protocol and forwarded to the laser payload in real time. 0xEB90 is VDES service data, which is sent to the VDES storage area of ​​the onboard data storage management unit for storage management.

[0018] Preferably, the interface of the VDES payload data processing unit adopts a three-wire LVDS, with a receiving operating frequency of 10MHz and a transmitting operating frequency of 2MHz.

[0019] Preferably, the S-band transceiver network unit includes one S-band uplink receiver and one S-band downlink transmitter, wherein,

[0020] The uplink receiver has a center frequency of 2245MHz, an operating frequency band of 2240MHz~2250MHz, a code rate of 1Mbps, uses (7 / 8)LDPC channel coding, and adopts QPSK modulation.

[0021] The downlink transmission has a center frequency of 2495 Mbps, an operating frequency band of 2490 MHz to 2500 MHz, a code rate of 5 Mbps, uses (7 / 8) LDPC channel coding, and employs QPSK modulation.

[0022] Preferably, the on-board data storage management unit adopts solid-state storage with a capacity of not less than 4Tbit and uses SLC-type NAND Flash. The storage management of different types of data on the satellite includes: an engineering parameter storage area for storing overall satellite engineering parameters, a VDES storage area for storing VDES payload data, a laser storage area for storing laser payload data, and a data transmission uplink storage area for storing data transmission uplink data. The size of each storage area can be reallocated in orbit.

[0023] Preferably, the spacecraft computer data processing unit interacts with the spacecraft computer via a CAN bus.

[0024] Preferably, the system further includes a power supply unit for converting the two 12V power supplies provided by the satellite into internal power, and has a surge suppression circuit.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] 1. This invention has the function of data interaction between the satellite's internal laser payload and the VDES payload;

[0027] 2. This invention has the function of data exchange between satellites;

[0028] 3. This invention has the capability to manage the partitioned storage of engineering parameters, VDES data, laser data, and uploaded data, and supports on-orbit adjustment of partition size;

[0029] 4. This invention supports the establishment of downlink and uplink satellite-to-ground links between satellite and ground via the S-band, enabling the function of satellite data downlink and ground data uplink;

[0030] 5. This invention only requires an external 12V secondary voltage, while other voltages are generated internally, thus requiring less power for the entire satellite. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the laser payload, VDES payload, spaceborne computer, and S-band network data stream of the present invention;

[0032] Figure 2 This is a schematic diagram of the downlink data stream output between satellite and ground stations;

[0033] Figure 3 This is a schematic diagram of the uplink data stream output between satellite and ground stations;

[0034] Figure 4 This is a schematic diagram of the internal voltage transformation of the present invention. Detailed Implementation

[0035] The purpose of this invention is to realize the storage management and data forwarding of on-orbit data of payloads such as on-board laser payloads, VDES payloads, and satellite computers, and to build a satellite-to-ground link to realize the mutual transmission of data between satellites and ground stations.

[0036] The main functions of this system are to transmit and receive data for laser communication payload A(B); transmit and receive data for VDES payload A / B; process and forward data exchanged between VDES payload and laser payload according to the protocol; receive and demodulate uplink data transmission signals from the S-band transceiver network; send and modulate downlink data transmission signals, convert them to the S-band frequency, output them to the S-band transceiver network, and then output them to the QV transceiver.

[0037] The system includes:

[0038] The laser payload data processing unit is used to complete data interaction between the system and the laser payload. The interface adopts a three-wire LVDS, and the clock frequency for both receiving and transmitting is 60MHz. The laser payload adopts a cold standby mode, supporting only one payload to operate independently in orbit at a time. The laser payload data receiving and data format detection unit is used to complete the serial-to-parallel conversion and format detection of the laser payload data. In one embodiment, if data bytes B0 to B3 are 0xFAF32000, they are valid data; otherwise, they are invalid data. If data bytes B4 to B5 are 0x47F8, the data is laser inter-satellite data, which needs to be restored to the original data according to the protocol and then forwarded to the VDES payload in real time. Other data is laser service data, which requires on-orbit data storage management.

[0039] The VDES payload data processing unit is used to complete data interaction between the system and the VDES payload. The interface adopts a three-wire LVDS, with a receiving clock frequency of 10MHz and a transmitting clock frequency of 2MHz. The VDES payload adopts a hot standby mode, which can support one payload to work independently in orbit or two payloads to work in orbit simultaneously. The VDES payload data reception and data format detection unit is used to complete the serial-to-parallel conversion and format detection of VDES payload data. In one embodiment, if the data bytes B0 to B1 are 0xEB90 or 0xEB9A, it is valid data; otherwise, it is invalid data. Among them, 0xEB9A is VDES inter-satellite data, which needs to be organized into transmission frames according to the protocol and forwarded to the laser payload in real time; 0xEB90 is VDES service data, which needs to be stored and managed in orbit.

[0040] The S-band transceiver network unit is used for data interaction between the system and the S-band transceiver network. After the satellite enters orbit, if a downlink task is initiated, the onboard data is replayed and assembled into a transmission frame for transmission to the ground station; if an uplink task is initiated, the data frames from the ground station are received and forwarded to the corresponding payload according to the protocol. In one embodiment, the S-band transceiver network has one S-band uplink receiver and one S-band downlink transmitter. Its uplink center frequency is 2245MHz, operating frequency band is 2240MHz~2250MHz, code rate is 1Mbps, (7 / 8) LDPC channel coding is used, the modulation method is QPSK, and the acquisition time is no more than 8s; the downlink center frequency is 2495Mbps, operating frequency band is 2490MHz~2500MHz, code rate is 5Mbps, (7 / 8) LDPC channel coding is used, the modulation method is QPSK, and the carrier frequency accuracy is no more than 2×10 -6 .

[0041] The onboard data storage management unit is used to manage the storage of onboard data. It supports four fixed storage partitions: an engineering parameter storage area, a VDES storage area, a laser storage area, and a data transmission uplink area. The engineering parameter storage area stores the overall satellite engineering parameters; the VDES storage area stores VDES A / B data; the laser storage area stores laser communication payload A(B) data; and the data transmission uplink area stores data uploaded via data transmission uplink. In one embodiment, the solid-state storage capacity of the onboard data storage management unit is no less than 4 Tbit, using SLC-type NAND Flash. The initial storage partition allocation is as follows: 256 Gbit for the engineering parameter storage area, 2 Tbit for the VDES storage area, 1 Tbit for the laser storage area, and 768 Gbit for the data transmission uplink area. Storage partitions can be reallocated in orbit.

[0042] The satellite computer data processing unit is used for command execution and status monitoring between the system and the satellite computer. The system interacts with the satellite computer via a CAN bus. On one hand, it executes commands from the satellite computer, performs on-orbit tasks, and simultaneously reports the system's status back to the satellite computer. On the other hand, it receives engineering parameters from the satellite computer and manages on-orbit data storage. In one embodiment, the satellite computer unit communicates with the satellite computer via the CAN bus, collects internal telemetry data and sends it to the satellite, executes and forwards remote control commands from the satellite, and completes on-orbit tasks. Simultaneously, it stores engineering parameters from the satellite and transmits them to the ground after the satellite enters orbit to analyze the on-orbit operating status of the satellite computer.

[0043] The power supply unit is used for satellite power supply to the system. The satellite provides the system with two 12V secondary voltages, and the system internally performs the conversion between 5V, 3.3V, 1.8V, and 1.5V. In one embodiment, the power supply unit receives two 12V secondary voltages from the satellite, with a voltage ripple of no more than 100mV. The system has internal surge suppression circuitry and the ability to convert the 12V voltage to 5V, 3.3V, 2.5V, 1.8V, 1.5V, 1.3V, 1.2V, 1.0V, and 0.75V for internal system use.

[0044] The system has the ability to exchange data between satellites, which is used to build a satellite constellation. Different satellites establish connections through laser links to achieve mutual data transmission.

[0045] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0046] Example

[0047] Embodiments of the present invention provide an on-orbit data processing system for laser and VDES payloads. This system enables data processing between laser and VDES payloads within a satellite, data exchange between different satellites, and data exchange between satellites and ground stations via a satellite-to-ground link.

[0048] like Figure 1 As shown, the system receives VDES payload A / B data via the LVDS interface (VDES payloads A and B can be hot-backed up). It determines the data type based on the frame header information. If B0-B1 is 0xEB90, it is a service data frame. The data is packetized according to the CCSDS102.0-B-5 packet telemetry protocol, and on-orbit storage management is completed. If B0-B1 is 0xEB9A, it is an inter-satellite data frame. After framing according to the laser communication payload protocol format, it is forwarded to laser communication payload A(B) in real time. The system also receives laser communication payload A(B) data via the LVDS interface (the laser payload is a cold backup). If the virtual channel is forwarded to the VDES payload, the VDES inter-satellite data frame encapsulated in the laser protocol is extracted and forwarded to VDES payloads A / B in real time. Otherwise, the data is packetized according to the CCSDS102.0-B-5 packet telemetry protocol, and on-orbit storage management is completed. The system provides a large-capacity solid-state storage device that supports four fixed storage partitions: the engineering parameter storage area, the VDES storage area, the laser storage area, and the data transmission uplink area. The engineering parameter storage area stores the entire satellite's engineering parameters, the VDES storage area stores VDES A / B data, the laser storage area stores laser communication payload A(B) data, and the data transmission uplink area stores ground data uploaded through the data transmission uplink channel.

[0049] After establishing a satellite-to-ground link upon entry, the satellite can send commands via its onboard computer to activate the data playback mode between the satellite and the ground, such as... Figure 2As shown: The system reads real-time operating parameter data, including data recorded in the operating parameter storage area, VDES storage area, and laser storage area, as well as VDES payload A / B data and laser communication payload A(B) data. It then assembles AOS transmission frames, performs LDPC channel coding, QPSK modulation, up-converts to the S-band, and outputs the data to the S-band transceiver network. In satellite-to-ground playback mode, the system supports sequential playback of each partition, playback by storage address, and playback by time. It supports autonomous erasure of each partition and command-based erasure of each / all partitions. It has bad block management and error correction capabilities and supports repartitioning and resizing of each partition. Furthermore, the system supports inter-satellite laser playback: it reads data from the VDES storage area and the data transmission upload storage area, assembles frames according to the laser communication payload protocol format, and sends them to laser communication payload A(B). If real-time VDES payload data is available, it simultaneously forwards the VDES payload real-time data to the laser communication network. It should be noted that the satellite-to-ground playback mode and the inter-satellite laser playback mode are mutually exclusive; and the VDES inter-satellite data frame real-time forwarding function is supported in both satellite-to-ground playback mode and inter-satellite laser playback mode.

[0050] After the satellite establishes a satellite-to-ground link upon entry, the system receives QV data transmission uplink data, such as... Figure 3 As shown: Based on the virtual channel, if the virtual channel is laser communication payload B reconstructed data, the B_PDU data field data in the uplink AOS frame is extracted and forwarded to laser communication payload B in real time via LVDS; if the virtual channel is laser communication payload A or B service data, the storage source packet is grouped and stored in the data transmission uplink area; if the virtual channel is VDES payload data, the B_PDU data field data in the uplink AOS frame is extracted and forwarded to VDES payload A / B in real time via LVDS; if the virtual channel is multiplexing modulator reconstructed data, the system processes it automatically and completes the on-orbit reconstructing.

[0051] Meanwhile, the system interacts with the satellite computer via the CAN bus, sending telemetry data reflecting the working status of the multiplexer, receiving control commands and system time information from the satellite computer, and completing the switching of the multiplexer's working mode and working status.

[0052] like Figure 4 The diagram shown is a schematic of the internal voltage transformation of the present invention.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A laser and VDES on-orbit data processing system, characterized in that, The system comprises a laser payload data processing unit, a VDES payload data processing unit, an S-band transceiver network unit, an on-board data storage management unit and a satellite computer data processing unit, wherein, The laser payload data processing unit is configured to receive data of the laser payload, perform serial-parallel conversion and format detection, transmit laser inter-satellite data to the VDES payload in real time after recovering the original data according to a protocol, and transmit laser service data to the on-board data storage management unit for storage management. The VDES payload data processing unit is configured to receive data of the VDES payload, perform serial-parallel conversion and format detection, transmit inter-satellite data to the laser payload in real time after organizing a transmission frame according to a protocol, and transmit VDES service data to the on-board data storage management unit for storage management. The S-band transceiver network unit is configured to establish downlink and uplink with a ground station, group frame the on-board data playback and transmit the same to the ground station, receive data of the ground station and transmit the same to the corresponding payload according to a protocol. The on-board data storage management unit is configured to complete storage management of different types of data on board and support on-orbit adjustment of the size of a storage partition. The satellite computer data processing unit is configured to execute remote control instructions of a satellite computer, execute on-orbit tasks and feed back the status of the system to the satellite computer, receive engineering parameters of the satellite computer and transmit the same to the on-board data storage management unit to complete on-orbit storage management of data.

2. The laser and VDES on-board data processing system of claim 1, wherein, The laser payload comprises more than one, and a cold standby mode is adopted, so that only one laser payload is supported to work independently on orbit at the same time; the VDES payload is one or more than one, and a hot standby mode is adopted, so that one VDES payload is supported to work independently on orbit at the same time or two VDES payloads are supported to work on orbit at the same time.

3. The laser and VDES on-board data processing system of claim 2, wherein, The processing process of the laser payload data processing unit comprises: serial-parallel conversion and format detection are performed on the received laser payload data, and if B0-B3 bytes are 0xFAF32000, the data is valid, otherwise, the data is invalid; for valid data, further judgment is performed: if B4-B5 are 0x47F8, the data is laser inter-satellite data, which is transmitted to the VDES payload in real time after being recovered to the original data according to a protocol; otherwise, the data is laser service data, which is transmitted to the laser storage area of the on-board data storage management unit for storage management.

4. The laser and VDES on-board data processing system of claim 2, wherein, The interface of the laser payload data processing unit adopts three-wire LVDS, and the clock frequency of receiving and transmitting is 60MHz.

5. The laser and VDES on-board data processing system of claim 2, wherein, The processing process of the VDES payload data processing unit comprises: serial-parallel conversion and format detection are performed on the received VDES payload data, and if B0-B1 bytes are 0xEB90 or 0xEB9A, the data is valid, otherwise, the data is invalid; wherein 0xEB9A is VDES inter-satellite data, which is transmitted to the laser payload in real time after being organized into a transmission frame according to a protocol; 0xEB90 is VDES service data, which is transmitted to the VDES storage area of the on-board data storage management unit for storage management.

6. The laser and VDES on-board data processing system of claim 2, wherein, The interface of the VDES load data processing unit adopts three-wire LVDS, receives a working frequency of 10 MHz, and transmits a working frequency of 2 MHz.

7. The laser and VDES on-board data processing system of claim 1, wherein, The S-band transceiving network unit comprises one S-band uplink receiving and one S-band downlink transmitting, The center frequency of the uplink receiving is 2245 MHz, the working frequency band is 2240-2250 MHz, the code rate is 1 Mbps, (7 / 8) LDPC channel coding is adopted, and the modulation mode adopts QPSK; The center frequency of the downlink transmitting is 2495 Mbps, the working frequency band is 2490-2500 MHz, the code rate is 5 Mbps, (7 / 8) LDPC channel coding is adopted, and the modulation mode adopts QPSK.

8. The laser and VDES on-board data processing system of claim 1, wherein, The on-board data storage management unit adopts solid-state storage, and the capacity is not less than 4 Tbit, SLC type NAND Flash is adopted, and the on-board storage management of different types of data comprises: a work parameter storage area for storing the whole satellite engineering parameters, a VDES storage area for storing VDES load data, a laser storage area for storing laser load data, and a data transmission uplink storage area for storing data transmission uplink data, and the size of each storage area supports on-orbit reallocation.

9. The laser and VDES on-board data processing system of claim 1, wherein, The on-board computer data processing unit interacts with the on-board computer through a CAN bus.

10. The laser and VDES on-board data processing system of claim 1, wherein, The system further comprises a power unit for converting two 12V power provided by the satellite into internal power, and having a surge suppression circuit.

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