A TT&C transponder of a low earth orbit satellite constellation and a mass production method thereof

Abstract

The application provides a low-orbit satellite constellation TT&C transponder and a batch production method thereof, and belongs to the field of satellite communication equipment. In view of the problems of complicated configuration, low batch production efficiency and insufficient on-orbit reliability of the satellite transponder in the prior art, the application proposes a layered configurable design: including a radio frequency front end, a baseband signal processing module, a configuration management module and a configuration storage chip. The flexible setting of parameters such as frequency points, power and spread spectrum code groups is supported; the on-orbit rewriting mechanism of the configuration storage chip can recover abnormal states, ensuring high reliability. At the same time, the application provides a batch production method, including storage parameter power-on loading, parallel testing and on-orbit temporary modification, which significantly shortens the testing time, adapts to the iterative upgrading demand of satellites, and takes into account flexible deployment and on-orbit safety.

Description

Technical Field

[0001] This invention belongs to the field of satellite communication equipment, and in particular, relates to a telemetry, tracking, and command (TT&C) transponder for a low-Earth orbit (LEO) satellite constellation. Furthermore, this invention also relates to a method for mass-producing TT&C transponders for LEO satellite constellations. Background Technology

[0002] In recent years, satellite internet has entered a period of rapid development, with low-Earth orbit satellite constellations gradually replacing the traditional single-satellite operating mode and achieving global coverage through multi-satellite networking. The core characteristic of such constellations (such as the Qianfan constellation) lies in the need for ultra-fast mass production and intensive launch of satellites. Against this backdrop, satellite systems must possess continuous iterative upgrade capabilities, and their key equipment, such as telemetry, tracking, and command (TT&C) transponders, must support flexible configuration and rapid on-orbit upgrades in core parameters such as spreading codes and communication rates.

[0003] In integrated electronic systems, the performance of the telemetry, tracking, and command (TT&C) transponder plays a decisive role in the operation of low-Earth orbit (LEO) satellites and is a key factor in the success or failure of satellite-to-ground communication. Each satellite in a constellation has specific spreading codes, transmit power, operating frequencies, and data rates, which traditionally required specialized configuration before the satellites left the factory. However, this approach consumes significant manpower, resources, and equipment for testing and maintenance, making it unsuitable for the rapid pace of mass satellite production and unable to meet the needs of iterative upgrades of satellite systems.

[0004] Ground equipment typically employs an "open-source configuration" design philosophy, such as reserving software interfaces to tolerate occasional errors, which can be recovered by restarting, in pursuit of flexible deployment. However, satellites cannot be physically repaired after they are in orbit, and any failure could lead to mission termination; onboard equipment must adhere to the "Failure Mode, Effects, and Diagnostic Analysis (FMEDA)" principle, ensuring "absolute reliability" through redundancy, fault tolerance, and self-checking mechanisms. Simply transplanting the flexible configuration scheme of ground equipment into existing transponder designs will not meet the on-orbit reliability requirements.

[0005] Therefore, there is an urgent need for a telemetry, tracking, and command (TT&C) transponder solution that can achieve rapid mass production and deployment while also ensuring on-orbit reliability, providing technical support for the efficient iterative upgrade of low-Earth orbit constellations while ensuring the safe operation of satellites throughout their entire lifecycle. Summary of the Invention

[0006] This invention provides a telemetry, tracking, and command transponder suitable for low-Earth orbit satellite constellations and a method for mass production thereof, which solves the dual challenges of satellite iterative upgrade requirements and on-orbit safe operation, while taking into account both flexible deployment and reliability.

[0007] The measurement and control transponder includes a radio frequency front-end, an AD chip, an FPGA platform, a configuration storage chip, and an external refresh chip; The radio frequency front end is used to receive uplink signals and send downlink signals; The AD chip is used to receive signals emitted by the RF front end, convert them, and then send them to the FPGA platform. The FPGA platform includes a baseband signal processing module and a configuration management module; The baseband signal processing module is used to receive and process signals emitted from the AD chip; The configuration management module is connected to the RF front end and the baseband signal processing module respectively, and is used to output control signals of at least one of frequency point, power, rate, threshold, spreading code and loop parameters. The configuration storage chip is connected to the configuration management module and adopts a three-mode redundancy design and an on-orbit rewrite mechanism. The external refresh chip is connected to the FPGA platform, which monitors the working status of the FPGA platform in real time and triggers a reload when an error is detected, thereby restoring the FPGA platform's functionality.

[0008] Preferably, the RF front end further includes a frequency synthesizer and a filtering module; the uplink signal is processed into an intermediate frequency signal by the frequency synthesizer, and then sent to the AD chip after filtering; the AD chip is driven by the FPGA platform to convert the intermediate frequency signal into a low-to-medium frequency signal and send it to the baseband signal processing module.

[0009] Preferably, the signal transmission power of the radio frequency front end is set with multiple adjustable levels and has a real-time adjustment function.

[0010] Preferably, the baseband signal processing module can adapt to uplink signals with various information rates emitted by the AD chip, and achieve adaptive output of downlink signals by dynamically analyzing the uplink signals.

[0011] Preferably, the configuration management module receives instructions via an interface, including: a configuration storage interface for connecting to the configuration storage chip and implementing automatic loading upon power-on; an asynchronous serial port interface for receiving instructions to perform on-orbit temporary parameter modification or function reconfiguration operations; and a debugging interface for status detection of the RF front-end, AD chip, and FPGA platform, used only during desktop debugging.

[0012] Preferably, the triple redundancy design of the configuration storage chip includes: all configuration parameters are synchronously written to three independent storage units, and valid parameter values ​​are generated through a majority voting mechanism during output.

[0013] Preferably, the on-orbit rewrite mechanism of the configuration storage chip includes: restoring to the most recently valid configuration when an abnormal configuration parameter of any independent storage unit is detected through a voting mechanism.

[0014] Preferably, the present invention also provides a method for mass production of the above-mentioned telemetry and control transponder, comprising the following steps: S1. When manufacturing the telemetry and control transponder, configuration parameters are set for it, including at least one of frequency point, power, speed, threshold, spreading code and loop parameters, and the configuration parameters are stored in the configuration storage chip of the telemetry and control transponder; S2. Perform batch testing using the asynchronous serial port interface of the aforementioned measurement and control transponder; S3. In the test, a test sequence including at least one of connectivity test, communication test, performance test, instruction test and functional test shall be performed, and the test and control transponders that fail the test shall be troubleshooted and retested until they pass. S4. If there are any changes to the on-orbit system requirements before delivery, the configuration parameters will be flexibly changed according to the new system requirements.

[0015] Preferably, the configuration parameters are stored using a redundancy mechanism, synchronously written to three independent storage units, and valid parameter values ​​are output through a majority voting mechanism and a cyclic redundancy check code is attached during reading.

[0016] Preferably, the batch testing includes: connecting multiple telemetry and control transponders in parallel through a standardized asynchronous serial port interface, injecting test signals, and verifying the acquisition sensitivity, bit error rate, and power control accuracy under the configured parameters.

[0017] Preferably, during the testing process, when only the configuration parameters of a single satellite are updated, only the performance of the associated configuration items needs to be verified, and there is no need to re-verify the functions of the entire system.

[0018] The beneficial effects of this invention are as follows: By designing a transponder that includes both a radio frequency front-end and baseband signal processing unit, a unified configurable architecture design suitable for mass production of on-orbit satellites is achieved; a configuration management unit enables unified management of three configuration interfaces (MRAM storage, asynchronous serial port, and debugging interface), adapting to various needs such as single-board debugging, whole-satellite testing, on-orbit application, and on-orbit maintenance; ensuring necessary flexibility while guaranteeing maximum reliability; flexibly configuring information such as spreading codes, transmission power, application frequencies, rates, signal thresholds, and loop parameters of different satellites according to requirements, enabling flexible configuration for batch deployment and rapid iteration and unified testing and verification of functions; saving significant time and manpower costs; and improving reliability by redundantly configuring and detecting stored information to prevent operational anomalies caused by single-event upsets. Attached Figure Description

[0019] Figure 1 This invention relates to a telemetry and control transponder suitable for low-Earth orbit satellite constellations; Figure 2 This is for the mass production process applicable to the aforementioned telemetry and control transponder. Detailed Implementation

[0020] To facilitate the understanding of the technical solution of this patent by those skilled in the art, and to make the technical purpose, technical solution and beneficial effects of this patent clearer, and to fully support the scope of protection of the claims, the technical solution of this patent will be further and more detailed below in the form of specific cases.

[0021] like Figure 1 As shown, this embodiment provides a telemetry, tracking, and command (TT&C) transponder suitable for low-Earth orbit (LEO) satellite constellations, enabling rapid mass production, flexible configuration, and reliable on-orbit operation of satellite TT&C transponders.

[0022] The measurement and control transponder includes: a radio frequency front-end 100, an AD chip 200, an FPGA platform 300, a configuration storage chip 400, and an external refresh chip 500.

[0023] The radio frequency front-end 100 is used to receive uplink signals and transmit downlink signals. Preferably, the radio frequency front-end 100 may include a frequency synthesizer 101 and a filtering module 102. The frequency synthesizer 101 processes the received uplink signal into an intermediate frequency signal, such as an S-band intermediate frequency signal, and the filtering module 102 filters the intermediate frequency signal and sends it to the AD chip 200.

[0024] The signal transmission power of the radio frequency front-end 100 can be set to multiple adjustable levels and has a real-time adjustment function. The internal programmable components change their working state by receiving digital control commands sent from the FPGA platform 300. This allows the telemetry and control transponder to flexibly adjust the transmission power according to different orbital altitudes and communication distances, effectively saving satellite energy consumption.

[0025] The AD chip 200 is used to convert between analog and digital signals. The sampling rate, gain, and other operating parameters of the AD chip 200 are configured and driven by the FPGA platform 300 through a corresponding control interface (such as SPI), for example, matching the signal bandwidth at different information rates according to different sampling rates. In one embodiment, the AD chip 200 converts the intermediate frequency signal received from the RF front-end 100 into a mid-to-low frequency signal, such as 0, 10MHz, or 70MHz.

[0026] The FPGA platform 300 is the signal processing core of the telemetry and control transponder. Its internal logic can be divided into two major functional modules, including the baseband signal processing module 301 and the configuration management module 302.

[0027] The baseband signal processing module 301 receives low- and medium-frequency signals sent by the AD chip 200. The baseband signal processing module 301 can receive and adapt various information rate signals from the AD chip 200, and adaptively output downlink signals in real time.

[0028] The configuration management module 302 is connected to the RF front-end 100 and the baseband signal processing module 301 respectively, and configures them. The configuration management module 302 receives instructions through multiple interfaces, parses and executes configuration instructions, and distributes specific parameter control signals to various execution units, such as the RF front-end 100 and the baseband signal processing module 301.

[0029] Multiple types of interfaces may include, for example: The configuration storage interface reads preset default parameters from the configuration storage chip 400 upon power-up and automatically loads the parameters; for example, the MRAM storage interface reads default parameters from the MRAM configuration storage chip and loads them.

[0030] An asynchronous serial port interface is used to connect to the spacecraft computer to receive at least one of the following instructions: on-orbit temporary parameter modification, function reconfiguration, desktop modification, and on-orbit use. When the configuration management module 302 receives an instruction through the asynchronous serial port interface, it will distinguish between on-orbit temporary parameter modification and reconfiguration to decide whether to send the instruction signal directly to the specific execution unit or to the storage chip (such as the configuration storage chip 400) for solidification.

[0031] The debugging interface is used only during the testing and maintenance phase. It receives debugging commands from the testing equipment and stores the signals required by the developer's commands, so that the developer can troubleshoot and diagnose faults during the debugging process.

[0032] Furthermore, after fusing and parsing the received information, the configuration management module 302 generates and outputs control signals for the baseband signal processing module 301, the radio frequency front-end 100, and the AD chip 200. For example, it enables centralized control of at least one key parameter such as frequency, power, speed, threshold, spreading code, and loop parameters.

[0033] Furthermore, the baseband signal processing module 301 receives real-time parameters from the configuration management module 302 and performs signal acquisition, tracking, demodulation, and / or generation.

[0034] Preferably, the baseband signal processing module 301 also supports multiple sets of spreading codes, allowing for flexible switching between different spreading codes according to different task requirements. The spreading codes are stored simultaneously in the FPGA platform 300 and the configuration storage chip 400; the FPGA platform 300 stores N sets of immutable spreading codes written by the program, while the configuration storage chip 400 stores modifiable spreading codes that match the satellite number.

[0035] Preferably, when the baseband signal processing module 301 calls the spreading code, it can find the spreading code in the FPGA platform 300 according to the mapping relationship based on the final spreading code information in the local configuration storage chip 400.

[0036] Preferably, when the baseband signal processing module 301 calls the spreading code, it can also directly read and call the spreading code bit stream in the local configuration storage chip 400 that is not written to the FPGA platform 300, so as to ensure the independence and configurability of the spreading code.

[0037] The configuration storage chip 400 is connected to the configuration management module 302 via an MRAM storage interface. It stores the configuration parameters of the telemetry and control transponder, including one or more of the following: frequency, power, speed, threshold, spreading code, and loop parameters. The parameters are automatically loaded upon power-up. All configuration parameters of the configuration storage chip 400 are redundantly stored in three or more odd-numbered (e.g., three) independent storage units and output through a voting mechanism to prevent malfunctions caused by single-event upsets.

[0038] An external refresh chip 500 is connected to the FPGA platform 300 and detects the single-event status of the configuration RAM (CRAM) in the FPGA platform 300. When a single-event fault is detected, a full configuration area reload is triggered, and the original configuration file is re-injected from the external Flash memory (not shown) dedicated to storing the FPGA configuration bit stream into the FPGA platform 300 to restore the logic function.

[0039] During on-orbit operation, if a strong radiation event causes a data error in one of the storage cells of the configured storage chip 400, the system can automatically block the erroneous data through a voting mechanism, adopt the correct values ​​of the other two storage cells, and simultaneously initiate a rewrite mechanism to repair the damaged data.

[0040] Figure 2 The following is a flowchart of the mass production process for the measurement and control transponder of this invention: S1. Generate specific configuration parameter files for telemetry and control transponders at different satellite orbit positions, including at least one of frequency point, power, rate, threshold, spreading code and loop parameters, and store the configuration parameters in the configuration storage chip 400.

[0041] Configuration parameters are stored using a redundancy mechanism, synchronously written to three independent storage units. During retrieval, a majority voting mechanism is used to output valid parameter values, along with a cyclic redundancy check (CRC) code. This redundant storage and majority voting mechanism effectively prevents parameter errors caused by single points of failure, improving system reliability. If data in any storage unit becomes abnormal, the system can verify and recover the data from the other two storage units, ensuring the correctness of the configuration parameters.

[0042] S2. On the production line, batch testing is performed using the asynchronous serial port interface of the measurement and control transponder. The asynchronous serial port interface is connected to a dedicated testing device, and standard test signals are injected through the testing system.

[0043] S3. During the test, a test sequence including at least one of the following shall be executed: connectivity test, communication test, performance test, instruction test and functional test. For the transponders that fail the test, troubleshooting and retesting shall be carried out until they pass.

[0044] Connectivity testing primarily checks whether the physical connections between modules are normal; communication testing verifies the quality of the communication link between the telemetry and control transponder and the ground station; performance testing evaluates whether its operating parameters meet design requirements; command testing confirms whether its response to various commands conforms to specifications; and functional testing comprehensively examines the integrity and stability of its various functions.

[0045] S4. If there are any changes in on-orbit system requirements before delivery, the configuration parameters can be flexibly modified according to the new system requirements. This flexible configuration modification mechanism enables the telemetry and control transponder to adapt to the changing needs of different satellite missions without the need for hardware redesign, greatly improving the adaptability and reusability of the product.

[0046] The above description is merely a preferred 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 is determined by the scope of the claims.

Claims

1. A telemetry, tracking, and command transponder suitable for low-Earth orbit satellite constellations, characterized in that, It includes an RF front-end (100), an AD chip (200), an FPGA platform (300), a configuration memory chip (400), and an external refresh chip (500). The radio frequency front end (100) is used to receive uplink signals and send downlink signals; The AD chip (200) is used to receive the signal emitted by the radio frequency front end (100), convert it, and send it to the FPGA platform (300). The FPGA platform (300) includes a baseband signal processing module (301) and a configuration management module (302); the baseband signal processing module (301) is used to receive and process signals emitted from the AD chip (200); the configuration management module (302) is connected to the RF front-end (100) and the baseband signal processing module (301) respectively, and is used to control signals of at least one of the output frequency, power, rate, threshold, spreading code and loop parameters. The configuration storage chip (400) is connected to the configuration management module (302) and adopts a three-mode redundancy design. All configuration parameters are synchronously written to three independent storage units, and valid parameter values ​​are generated through a majority voting mechanism when outputting. The external refresh chip (500) is connected to the FPGA platform (300), which detects the working status of the FPGA platform in real time and triggers reloading when an error is detected to restore the FPGA platform function; The FPGA platform (300) also stores an immutable spreading code written by the program, and the configuration storage chip (400) also stores a changeable spreading code that matches the satellite number. The baseband signal processing module (301) is also used to select between the immutable spreading code and the modifiable spreading code according to different task requirements.

2. The telemetry and control transponder according to claim 1, characterized in that, The radio frequency front end (100) also includes a frequency synthesizer (101) and a filtering module (102); the uplink signal is processed into an intermediate frequency signal by the frequency synthesizer (101), and after filtering, it is sent to the AD chip (200); the AD chip (200) is driven by the FPGA platform (300) to convert the intermediate frequency signal into a low-to-medium frequency signal and send it to the baseband signal processing module (301).

3. The telemetry and control transponder according to claim 1, characterized in that, The signal transmission power of the radio frequency front-end (100) is set with multiple adjustable levels and has a real-time adjustment function.

4. The telemetry and control transponder according to claim 1, characterized in that, The baseband signal processing module (301) can adapt to uplink signals of various information rates emitted by the AD chip (200) and adaptively output downlink signals as needed.

5. The telemetry and control transponder according to claim 1, characterized in that, The configuration management module (302) receives instructions via an interface, including: A configuration storage interface is provided for connecting to the configuration storage chip (400) and implementing the automatic loading function upon power-on. An asynchronous serial port interface is used to receive commands to perform on-orbit temporary parameter modifications or function reconfiguration operations. The debugging interface is used only during the testing and maintenance phase to receive debugging commands to detect the status of at least one of the RF front-end (100), AD chip (200), and FPGA platform (300).

6. The telemetry and control transponder according to claim 1, characterized in that, The configuration storage chip (400) also includes an on-orbit rewrite mechanism: when an abnormal configuration parameter of any independent storage cell is detected through a voting mechanism, it is restored to the most recently valid configuration.

7. A method for mass production of the telemetry and control transponder as described in claim 1, characterized in that, Includes the following steps: When manufacturing the telemetry and control transponder, configuration parameters are set for it. The configuration parameters include at least one of frequency point, power, speed, threshold, spreading code and loop parameters, and the configuration parameters are stored in the configuration storage chip (400) of the telemetry and control transponder. Batch testing was performed using the asynchronous serial port interface of the telemetry and control transponder to verify the configuration parameters; In the test, a test sequence including at least one of connectivity test, communication test, performance test, instruction test and functional test is performed, and the test and control transponder that fails the test is troubleshooted and retested until it passes; If there are any changes to the on-orbit system requirements before delivery, the configuration parameters will be flexibly modified according to the new system requirements.

8. The method according to claim 7, characterized in that, The configuration parameters are stored using a redundancy mechanism, synchronously written to three independent storage units. When reading, the valid parameter values ​​are output through a majority voting mechanism and a cyclic redundancy check code is attached.

9. The method according to claim 7, characterized in that, The batch testing includes: Multiple telemetry and control transponders are connected in parallel via asynchronous serial ports to inject standard test signals.

10. The method according to claim 9, characterized in that, During the testing process, when only the configuration parameters of a single satellite are updated, only the performance of the associated configuration items needs to be verified, and there is no need to re-verify the functions of the entire system.

Images