Integrated Measurement, Control and Tracking System and Measurement, Control and Tracking Method

Abstract

This invention discloses an integrated telemetry, control, and tracking system and method. The integrated system includes: an FPGA signal processing module for obtaining zero-IF in-phase quadrature signals based on digitally received signals; a telemetry demodulation processing unit for obtaining telemetry data based on the zero-IF in-phase quadrature signals; a tracking processing unit for demodulating azimuth error voltage and elevation error voltage to guide the antenna to track the satellite; the FPGA signal processing module also generates remote control transmission signals; and a ZYNQ main control module connected to the FPGA signal processing module for configuring telemetry, control, and tracking operating parameters, and for data interaction and status monitoring of the telemetry data, remote control commands, equipment status, and tracking error data. This system solves the problems of low equipment integration, poor link coordination, and large overall size in traditional telemetry, control, and tracking solutions.

Description

Technical Field

[0001] This application relates to the field of satellite telemetry, tracking and control, and more specifically, to an integrated telemetry, tracking and control system and a telemetry, tracking and control method. Background Technology

[0002] Satellite internet, with its core advantages such as wide coverage, low latency, strong anti-interference capabilities, and flexible deployment, has become the core development direction of future global communication networks. The migration of traditional terrestrial 5G network users to satellite networks and the realization of global interconnection has become an inevitable industry trend. As the core infrastructure of the ground segment of satellite internet, the gateway station is a key intermediate node connecting the user side with the space satellite constellation. It undertakes core tasks such as satellite signal transmission and reception, telemetry and control data transmission, service scheduling, and protocol conversion. Its deployment scale will expand significantly with the large-scale construction of satellite internet.

[0003] The telemetry, tracking, and command (TT&C) baseband equipment is a core component of the gateway station system, directly determining the stability, reliability, and transmission efficiency of the TT&C link between the gateway station and the satellite. It is primarily responsible for the bidirectional transmission of TT&C data, rapid satellite signal acquisition, and precise self-tracking. It is a key device for ensuring uninterrupted satellite internet communication and enabling precise antenna guidance to satellites. Currently, SDR (Software Defined Radio) technology has become the mainstream technology in the field of radio engineering. Its core idea is to use open, scalable, and reconfigurable hardware as a general platform, implementing as many functions as possible through upgradeable and replaceable software. It has the advantages of flexible adaptation to various signal modes, easy functional expansion, and remote upgrades, and has been widely used in satellite TT&C, communications, and other fields.

[0004] In the field of satellite telemetry, tracking and control, traditional solutions often rely on independent equipment for telemetry, tracking and control functions, which results in low equipment integration, poor link coordination, and large overall size. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] To address the problems of low equipment integration, poor link coordination, and large overall size in traditional solutions where measurement, control, and tracking functions are mostly implemented by independent devices, this invention proposes, firstly, an integrated measurement, control, and tracking system, comprising: ZYNQ main control module, FPGA signal processing module, RF transceiver module and interface module; The radio frequency transceiver module is used to obtain a digital received signal based on the received satellite downlink radio frequency signal, and send the digital received signal to the FPGA signal processing module; The FPGA signal processing module is used to obtain zero-IF in-phase quadrature signals based on the digital received signals, and synchronously distribute the zero-IF in-phase quadrature signals to the measurement and control demodulation processing unit and the tracking processing unit. The measurement and control demodulation processing unit is used to obtain telemetry data based on the zero intermediate frequency in-phase quadrature signal; The tracking processing unit is used to demodulate the zero-IF in-phase quadrature signal to obtain the azimuth error voltage and the elevation error voltage, and outputs the azimuth error voltage and the elevation error voltage to the servo system through the interface module to guide the antenna to track the satellite; The FPGA signal processing module is also used to encode, spread, and modulate the remote control commands issued by the host computer, generate a remote control transmission signal, and output the remote control transmission signal through the radio frequency transceiver module. The ZYNQ main control module is connected to the FPGA signal processing module and is used to configure the measurement and control tracking working parameters, perform data interaction and status monitoring on the telemetry data, the remote control command, the equipment status and tracking error data, and provide feedback information to the tracking processing unit for adjusting the tracking parameters based on the telemetry data.

[0007] Secondly, the present invention also proposes a measurement and control tracking method for the system described in the first aspect, the method comprising: Receive satellite downlink radio frequency signals, perform gain control and analog-to-digital conversion on the satellite downlink radio frequency signals to obtain digital received signals; The digitized received signal is digitally down-converted and Doppler frequency offset compensated to obtain a zero intermediate frequency in-phase quadrature signal; The zero-IF in-phase quadrature signal is synchronously distributed to the measurement and control demodulation processing flow and the tracking processing flow; In the telemetry and demodulation process, based on the zero-IF in-phase quadrature signal, spread spectrum acquisition, pseudo-code tracking, carrier recovery, despreading, bit synchronization, frame synchronization and decoding are performed sequentially to obtain telemetry data; In the tracking process, the sum and difference signals are synchronized based on the zero intermediate frequency in-phase quadrature signal, demodulated to obtain azimuth error voltage and elevation error voltage, and the azimuth error voltage and elevation error voltage are output to the servo system to guide the antenna to track the satellite. The system receives remote control commands from a host computer, encodes, spreads, and modulates the remote control commands to generate a remote control transmission signal, and outputs the remote control transmission signal. Based on the telemetry data, the remote control command, the device status, and the tracking error data, the system monitors the tracking status and provides feedback information to the tracking processing flow for adjusting tracking parameters based on the telemetry data.

[0008] In summary, the integrated telemetry, telemetry, and tracking system proposed in this application unifies telemetry reception, remote control transmission, signal synchronization, tracking error extraction, and antenna servo guidance in the satellite telemetry and telemetry link into a single set of hardware and a single set of digital signal processing procedures. This eliminates the reliance on independent devices for telemetry and telemetry data processing and antenna tracking processing, allowing them to share the same RF receiver source, the same digital downconversion result, the same clock reference, and the same master control scheduling mechanism. Thus, after the satellite downlink signal is received, it is not first used separately by one device for telemetry demodulation and then another device to extract tracking error information. Instead, it is converted into a zero-IF in-phase quadrature signal in the FPGA signal processing module and simultaneously used by both the telemetry and telemetry demodulation unit and the tracking processing unit. Because both types of processing use the same digital signal at the same time, on the same sampling link, and after the same frequency offset compensation, the carrier synchronization and pseudocode synchronization required for telemetry and telemetry demodulation and the signal synchronization required for tracking error extraction can be kept consistent, reducing the accumulation of errors caused by sampling clocks, processing delays, frequency references, and interface transmissions between independent devices. Attached Figure Description

[0009] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic structural block diagram of an integrated measurement, control, and tracking system provided in this application embodiment; Figure 2 A schematic baseband diagram of an integrated measurement, control, and tracking system provided in this application embodiment; Figure 3 A schematic diagram of spread spectrum modulation for an integrated measurement, control, and tracking system provided in this application embodiment; Figure 4 A schematic diagram illustrating the telemetry processing principle of an integrated measurement, control, and tracking system provided in this application embodiment; Figure 5 A flowchart of a dual-channel tracking signal for an integrated measurement, control, and tracking system provided in this application embodiment; Figure 6 This is a schematic flowchart illustrating a measurement and control tracking method provided in an embodiment of this application. Detailed Implementation

[0010] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0011] To address the problems of low equipment integration, poor link coordination, and large overall size in traditional solutions where measurement, control, and tracking functions are mostly implemented by independent devices, this application provides an integrated measurement, control, and tracking system, comprising: ZYNQ main control module, FPGA signal processing module, RF transceiver module and interface module; The radio frequency transceiver module is used to obtain a digital received signal based on the received satellite downlink radio frequency signal, and send the digital received signal to the FPGA signal processing module; The FPGA signal processing module is used to obtain zero-IF in-phase quadrature signals based on the digital received signals, and synchronously distribute the zero-IF in-phase quadrature signals to the measurement and control demodulation processing unit and the tracking processing unit. The measurement and control demodulation processing unit is used to obtain telemetry data based on the zero intermediate frequency in-phase quadrature signal; The tracking processing unit is used to demodulate the zero-IF in-phase quadrature signal to obtain the azimuth error voltage and the elevation error voltage, and outputs the azimuth error voltage and the elevation error voltage to the servo system through the interface module to guide the antenna to track the satellite; The FPGA signal processing module is also used to encode, spread, and modulate the remote control commands issued by the host computer, generate a remote control transmission signal, and output the remote control transmission signal through the radio frequency transceiver module. The ZYNQ main control module is connected to the FPGA signal processing module and is used to configure the measurement and control tracking working parameters, perform data interaction and status monitoring on the telemetry data, the remote control command, the equipment status and tracking error data, and provide feedback information to the tracking processing unit for adjusting the tracking parameters based on the telemetry data.

[0012] Also includes: The clock management module provides a synchronization clock to the ZYNQ main control module, the FPGA signal processing module, and the RF transceiver module, so that the measurement and control demodulation process, the remote control modulation process, and the tracking process are executed under the same clock reference. For example, the RF transceiver module can be constructed using a multi-channel RF transceiver chip. The receiving channel connects to an external SMA RF interface, enabling it to receive sum, difference, or other tracking-related input signals. For telemetry reception scenarios, the RF transceiver module can operate in the corresponding frequency band and bandwidth according to its configuration, and use automatic gain control to bring the received signal into a stable digital sampling range. For remote control transmission scenarios, the digital remote control baseband or intermediate frequency signal generated by the FPGA signal processing module is sent to the RF transceiver module, undergoes digital-to-analog conversion, up-conversion, and RF amplification, and is finally transmitted to the satellite through the RF output interface. In other words, the same RF transceiver module handles both downlink signal acquisition and uplink remote control signal output, eliminating the need for separate configurations of telemetry and control receiving RF links, tracking receiving RF links, and remote control transmitting RF links, achieving hardware-level integration.

[0013] For example, the FPGA signal processing module can be configured with a digital down-conversion unit, a measurement and control demodulation processing unit, a tracking processing unit, and a remote control modulation processing unit. After receiving the sampled data output from the RF transceiver module, the digital down-conversion unit generates a zero-IF in-phase quadrature signal according to the carrier frequency, sampling rate, bandwidth, and frequency offset compensation parameters issued by the ZYNQ main control module. Then, the FPGA internally sends this zero-IF in-phase quadrature signal simultaneously to the measurement and control demodulation processing unit and the tracking processing unit via a parallel data path. The two processing units receive baseband data within the same processing cycle, rather than having one unit process the data and then forward it to the other. This ensures that the measurement and control demodulation and tracking error extraction remain consistent in terms of time reference and signal state.

[0014] For example, after receiving a zero-IF in-phase quadrature signal, the telemetry and demodulation processing unit can first perform spread spectrum acquisition according to the configured pseudocode type and code rate. After successful acquisition, the pseudocode tracking loop adjusts the local pseudocode phase based on the early-late correlation results, and the carrier recovery loop adjusts the local carrier based on the phase error information between the in-phase quadrature components. The signal synchronized by the pseudocode and carrier is despread, the spread spectrum gain is released, and the data energy originally spread over a wider frequency band is reconcentrated onto the information symbols. Subsequently, bit synchronization determines the symbol decision time, frame synchronization determines the telemetry frame boundary, and decoding processing recovers the telemetry bits or telemetry frame data according to the preset encoding rules. The obtained telemetry data is then sent to the ZYNQ main control module via a high-speed bus, where ZYNQ stores, distributes, displays, or performs further status analysis.

[0015] For example, the tracking processing unit can obtain the in-phase quadrature signal corresponding to the sum path and the in-phase quadrature signal corresponding to the difference path from the data distributed internally by the FPGA. After pseudocode recovery and carrier recovery, the sum path signal provides a synchronization reference for the difference path signal. The difference path signal undergoes coherent processing, integration, and detection under this synchronization reference to obtain a voltage quantity related to the antenna deviation. If the azimuth error voltage is positive, it indicates that the antenna may be deflected to one side in the azimuth direction; if the azimuth error voltage is negative, it indicates that the antenna is deflected to the other side. The elevation error voltage can also be represented in a similar way to indicate the deviation in the elevation direction. The interface module outputs these error voltages to the servo system in the form of analog, digital, or serial communication data, enabling the antenna to follow the satellite's movement based on real-time error information.

[0016] For example, the host computer can send remote control commands to the ZYNQ main control module via network, serial port, or other interfaces. After performing format checks, parameter matching, and transmission timing management on the commands, the ZYNQ main control module hands them over to the FPGA signal processing module. The FPGA generates a remote control transmission signal according to preset encoding methods, pseudo-code sequences, code rates, modulation schemes, and transmission frequency parameters. This remote control transmission signal is then converted from digital to analog and up-converted by the RF transceiver module before being output to an external RF link, and then transmitted to the satellite via a power amplifier or antenna system. Since remote control transmission and telemetry reception are both configured by the same main control module and operate under the same clock system, the remote control transmission time, telemetry reception status, and tracking status can be uniformly recorded and correlated.

[0017] For example, the ZYNQ master control module provides feedback information to the tracking processing unit based on telemetry data for adjusting tracking parameters. The underlying principle is that telemetry data is not only passively received service data, but also reflects satellite link status, signal quality, frame synchronization stability, and demodulation reliability. When telemetry data or related demodulation status indicates a decline in current link quality, ZYNQ can combine this with tracking error data to determine whether adjustments to the tracking processing unit's parameters are necessary. For instance, it can adjust the tracking loop bandwidth to improve system responsiveness during rapid dynamic changes; it can also adjust the error voltage output smoothing parameters to prevent excessive servo system activity during short-term signal fluctuations; and it can determine whether to maintain the current tracking strategy or enter a reacquisition preparation state based on frame synchronization and lock status. The ZYNQ master control module can interact with the FPGA signal processing module via a high-speed bus. For large-capacity telemetry data, it can enter the buffer, storage unit, or network distribution interface through a high-speed data channel; for status and control quantities, reading and writing can be completed through register mapping or a low-speed control bus. The application software running on the ZYNQ provides local and remote control interfaces, allowing operators to view the current acquisition status, carrier lock status, telemetry frame synchronization status, bit error rate, tracking error voltage, device temperature, power supply voltage, and interface status. In case of abnormal situations, the application software can generate alarms and log them.

[0018] For example, the clock management module may include a high-stability local oscillator, a clock distribution chip, and an external reference clock input interface. The device can preferentially use an external high-precision reference clock, or use an internal clock when the external reference is unavailable. The clock management module allocates the reference clock to the RF transceiver module for sampling and frequency conversion, to the FPGA for digital signal processing, and to the ZYNQ for data scheduling, time recording, and status management. Since all modules operate under the same clock reference, a stable time correspondence can be established between telemetry demodulation results, remote control transmission times, and tracking error outputs.

[0019] like Figure 1 As shown in the diagram, the KU115 chip on the left corresponds to the aforementioned FPGA signal processing module, namely a high-speed digital signal processing unit with the XCKU115 as its core. The PL and PS chips on the right correspond to the programmable logic section and processor system section within the ZYNQ main control module. The PL side is used for high-speed logic interaction with the FPGA signal processing module, while the PS side is used to run the embedded operating system, management software, network communication, and task control. The AD9361*2 module in the diagram corresponds to a dual AD9361 RF transceiver module, providing multiple RF receive and transmit channels to simultaneously meet the requirements of telemetry reception, remote control transmission, and sum / difference tracking signal processing. Figure 1The left side also shows several external interfaces. The J30J interface connects to RS422, RS232, electronic level, and AD / DA signals. Among them, the RS422, RS232, and TTL interfaces can be used for device control, status interaction, and measurement and control data transmission, while the AD / DA interface can be used for analog signal acquisition or error voltage output. The 128Mb FLASH module and 16Gb DDR4 module in the figure indicate that the FPGA signal processing module is configured with firmware storage and high-speed cache resources. The FLASH is used to store configuration or startup-related data, and the DDR4 is used to cache high-speed sampling data, related processing data, telemetry data, or tracking processing data. Figure 1 Next to the ZYNQ section on the right are labels indicating 256Mb FLASH, 8GB eMMC, and 8Gb DDR3, signifying that the ZYNQ main control module is equipped with boot storage, system storage, and running memory. FLASH can be used to store the boot program or part of the firmware, eMMC can be used to store the operating system, application software, log files, and task configurations, and DDR3 is used for runtime data caching. The RJ45, UART, USB, and Type-C interfaces on the right correspond to the network interface, serial debugging interface, and local maintenance interface mentioned in the main text. RJ45 is used for remote control, data distribution, and software management, while UART, USB, or Type-C can be used for debugging, upgrades, or maintenance. The SMA and AD917 connections at the bottom of the diagram represent external clock or RF-related input / output paths. It should be noted that the aforementioned clock management module can use the AD9517-4ABCPZ clock chip.

[0020] like Figure 2As shown, the main baseband algorithms are all implemented in the FPGA signal processing module. After the satellite downlink and differential signals are received, they are first demodulated and despread on the receiving side, and then the telemetry data is recovered. This process corresponds to the telemetry and control demodulation process in the claims, that is, spreading acquisition, pseudocode tracking, carrier recovery, despreading, bit synchronization, frame synchronization and decoding are performed on the zero intermediate frequency in-phase quadrature signal to obtain telemetry data. The differential signal is downconverted and filtered, and then used for antenna tracking error demodulation. The differential signal usually contains antenna pointing deviation information, and after tracking demodulation, the azimuth error and elevation error can be obtained. This process corresponds to the tracking processing unit in the aforementioned system scheme, that is, the azimuth error voltage and elevation error voltage are obtained based on the synchronous processing of the sum and differential signals, and then output to the servo system. The device can not only receive satellite downlink telemetry signals, but also generate uplink remote control signals or analog signals. The remote control commands are encoded, spread by pseudocode and modulated to form radio frequency output signals, which are used to send remote control data to the satellite. The "remote control / telemetry simulation" here indicates that the baseband device can also support test or simulation scenarios, such as simulating remote control or telemetry signals in ground testing to verify the link processing capabilities. The remote control transmission signal can be branched into the small loop detection path. The small loop receiving unit demodulates the branched small loop detection signal, extracts the small loop remote control data, and compares it with the original remote control command to verify the correctness of the data generated by the remote control transmission link. The comparison result can be read and reported by the FPGA or ZYNQ.

[0021] like Figure 3 As shown, before modulation, remote control commands need to form a stable data stream according to the remote control information code clock. This data stream carries the remote control commands issued by the host computer or telemetry and control center. The device can also generate telemetry data streams for telemetry simulation or test scenarios. Through this path, the device can generate simulated telemetry data during ground testing to verify the backend receiving, demodulating, decoding, or data distribution functions. The selection module is used to select one of the remote control data stream and telemetry data stream as the subsequent modulation input, indicating that the spread spectrum modulation link can be reused for different task modes. The system generates spread spectrum pseudocode according to the preset pseudocode code clock. After the spread spectrum code is generated, it enters the XOR module together with the selected data stream. Here, XOR represents the chip-level expansion process in direct sequence spread spectrum, that is, the information data and pseudocode sequence are processed modulo-2 to expand the spectrum of the original data. The spread spectrum signal enters BPSK modulation, then enters up-conversion, and finally forms an output RF or IF transmit signal. After the host computer issues the remote control command, the system first forms a remote control data stream, then performs spread spectrum processing with the pseudo-code, and then performs BPSK modulation and up-conversion output.

[0022] like Figure 4As shown, bit synchronization is used to determine the optimal decision time for received data. After the preceding carrier recovery and despreading, the signal still needs to determine the sampling position of each bit or symbol. If bit synchronization is inaccurate, the decision point may fall in the symbol transition region, leading to an increased bit error rate. After bit synchronization, the data enters Viterbi decoding. Viterbi decoding is typically used for maximum likelihood decoding of convolutionally coded data, which can correct a certain number of transmission errors based on coding constraints, improving the reliability of telemetry data recovery. Code transformation is used to convert the decoded data into the data format required for subsequent frame processing. Different satellite telemetry systems may use different code types, polarities, or data arrangements; code transformation can convert the data recovered from the preceding stage into a unified format. Then, frame synchronization and descrambling are performed. This step is used to identify telemetry frame boundaries and remove the effects of scrambling. Frame synchronization enables the system to know where a frame of telemetry data begins and ends; descrambling is used to recover the data sequence that has been processed by scrambling. In cases where subframes exist in the telemetry data structure, the system also needs to further identify the subframe boundaries. Subframe synchronization is typically used in complex telemetry formats to ensure that subsequent data interpretation accurately corresponds to parameter positions. Finally, RS-decoded data packaging and reporting indicates that the system performs Reed-Solomon decoding or corresponding error correction on the synchronized data and packages and reports the recovered telemetry data to the main control software, host computer, or backend telemetry and control system.

[0023] In some examples, the tracking processing unit includes a sum path processing subunit, a difference path processing subunit, an amplitude normalization subunit, and an error voltage demodulation subunit; The sum-path processing subunit is used to perform pseudocode recovery and carrier recovery based on the sum-path signal, and to provide signal synchronization results to the measurement and control demodulation processing unit. The differential path processing subunit is used to receive differential path signals; The amplitude normalization subunit is used to perform amplitude normalization processing on the differential signal based on the automatic gain control voltage corresponding to the sum signal, so as to reduce the impact of the gain difference between the sum channel and the differential channel on the error voltage demodulation. The error voltage demodulation subunit is used to perform phase shifting, integration and detection processing on the amplitude-normalized differential signal to obtain the azimuth error voltage and the elevation error voltage.

[0024] For example, the tracking processing unit can be implemented in the FPGA signal processing module and includes a sum processing subunit, a difference processing subunit, an amplitude normalization subunit, and an error voltage demodulation subunit. After receiving the externally input sum and difference signals, the RF transceiver module converts them into digital signals and sends them to the FPGA signal processing module. The FPGA performs digital down-conversion on the sum and difference signals respectively to obtain corresponding zero-IF in-phase quadrature data. To ensure the time correspondence between the two channels, the sum and difference data can use the same sampling clock, the same digital processing cycle, and a unified timestamp, so that subsequent error demodulation will not deviate due to different processing delays between channels. After receiving the sum signal, the sum processing subunit first performs pseudocode recovery and carrier recovery based on preset pseudocode type and carrier frequency parameters. Pseudocode recovery is used to determine the code phase of the received spread spectrum signal, enabling the local pseudocode to align with the pseudocode in the received signal; carrier recovery is used to determine the carrier phase and frequency of the received signal, providing a stable phase reference for subsequent processing. After completing the above processing, the sum-path processing subunit provides the obtained signal synchronization result to the telemetry and control demodulation processing unit, enabling the telemetry and control demodulation processing unit to perform despreading, bit synchronization, frame synchronization, and decoding based on the synchronization result. Thus, the sum-path processing subunit not only serves tracking processing but also provides a synchronization basis for telemetry and control demodulation, thereby achieving data coordination between telemetry and control processing and tracking processing. The differential path processing subunit receives differential path signals. Differential path signals can include azimuth differential path signals and elevation differential path signals, or differential signals generated by an external feed network or comparator network. The differential path processing subunit performs sampling alignment, filtering, digital down-conversion, and data buffering on the differential path signals, enabling them to be called by the error voltage demodulation subunit within the same processing cycle as the sum-path synchronization result. For cases with both azimuth and elevation differential path inputs, the differential path processing subunit can generate azimuth differential path data and elevation differential path data separately, and subsequently generate azimuth error voltage and elevation error voltage respectively. The amplitude normalization subunit receives the differential path data output from the differential path processing subunit and simultaneously reads the automatic gain control voltage corresponding to the sum path signal. This automatic gain control voltage can be provided by the RF transceiver module or estimated by the FPGA based on the sum path signal amplitude. The amplitude normalization subunit determines the gain adjustment amount experienced by the current sum path signal based on the automatic gain control voltage, and then performs amplitude correction on the differential path data according to a preset mapping relationship. For example, when the automatic gain control voltage indicates that the current receiving link is in a high-gain state, it means that the original received signal is weak, and the amplitude change of the differential path signal may include link attenuation factors. The normalization subunit can reduce the impact of this link attenuation factor on error demodulation. When the automatic gain control voltage indicates that the current receiving link is in a low-gain state, it means that the original received signal is strong, and the normalization subunit can prevent the differential path amplitude from being too large, which could lead to error voltage saturation.The error voltage demodulation subunit receives the amplitude-normalized differential signal and performs phase-shifting processing based on the phase synchronization result provided by the sum-path processing subunit. After phase shifting, the error voltage demodulation subunit integrates the differential signal to accumulate effective components related to pointing deviation within a preset integration period, while suppressing random noise. Subsequently, the error voltage with directional meaning is obtained through detection processing. If the system processes both azimuth and elevation differential signals simultaneously, it outputs azimuth and elevation error voltages respectively. The output can be in digital form, or it can be converted into an analog voltage through digital-to-analog conversion and output to the servo system via the interface module.

[0025] like Figure 5 As shown, the sum signal is mainly used to establish a stable carrier and pseudocode synchronization reference, while the difference signal is mainly used to extract antenna pointing error information. The two are processed synchronously in the same digital baseband platform, and finally output the azimuth and elevation errors, which are used by the servo system to control the antenna to track the satellite.

[0026] In some examples, the FPGA signal processing module also includes a remote control loop receiver unit; The remote control loop receiving unit is used to receive the loop detection signal obtained by splitting the remote control transmission signal, perform spread spectrum demodulation processing on the loop detection signal, extract the loop remote control data, and compare the loop remote control data with the original remote control command sent by the host computer bit by bit to obtain the remote control loop comparison result. The comparison range of the bitwise comparison includes the pre-complementary sequence, the instruction text, and the post-complementary sequence. The ZYNQ main control module is used to receive and report the comparison results of the remote control ring.

[0027] For example, the host computer first generates or issues the original remote control command, which may include a command identifier, target satellite identifier, command text, verification field, and transmission control information. After receiving the original remote control command, the ZYNQ main control module sends it to the FPGA signal processing module. The FPGA signal processing module encodes, spreads, and modulates the original remote control command according to a preset remote control system to generate a remote control transmission signal. One path of the remote control transmission signal is sent to the RF transceiver module for output, and the other path is sent to the remote control small loop receiving unit via a split path as a small loop detection signal. The remote control small loop receiving unit performs spread spectrum demodulation processing on the small loop detection signal. Specifically, after the small loop detection signal enters the remote control small loop receiving unit, it is first frequency-processed according to a preset carrier center frequency to ensure the signal falls within a suitable baseband or low-IF range for demodulation; then, a pseudo-code sequence matching the remote control signal is used for correlation processing to recover the data symbols before spread spectrum; next, bit synchronization and frame synchronization are performed to determine the bit decision time and data frame boundaries; finally, the small loop remote control data is extracted. Since the small loop detection signal originates from the remote control transmission signal branch, the small loop remote control data recovered by the remote control small loop receiving unit can reflect the actual signal content generated by the remote control transmission link. After obtaining the small loop remote control data, the FPGA or ZYNQ main control module performs a bit-by-bit comparison with the original remote control command. The bit-by-bit comparison can start from the pre-completion sequence, comparing the small loop remote control data bit by bit with the corresponding fields in the original remote control command; then continue comparing the command text; and finally compare the post-completion sequence. If all bits match, a comparison pass result is generated; if there are inconsistencies, a comparison failure result is generated, and the error location can be further recorded. For example, if the error occurs in the pre-completion sequence, it may indicate an abnormality in the generation of the synchronization preamble; if the error occurs in the command text, it may indicate a data error in the encoding, buffering, or modulation process; if the error occurs in the post-completion sequence, it may indicate an abnormality in the generation of the frame tail or the truncation of transmission. After receiving the remote control small loop comparison result, the ZYNQ main control module can report it through the network interface, serial port, or host computer interface. The reported content can include the current remote control command number, transmission time, whether the comparison passed, the number of error bits, the range of error fields, and the device status. For automated testing scenarios, the ZYNQ main control module can also record the small-loop comparison results of multiple remote control transmissions as test logs, used to statistically analyze the stability of the remote control transmission link. For mission execution scenarios, the ZYNQ main control module can use the small-loop comparison results as part of the remote control transmission status, allowing operators to determine whether to continue executing subsequent remote control tasks. For example, in a satellite payload power-on task, the host computer issues a payload power-on remote control command. The FPGA completes encoding, spreading, and modulation to generate a remote control transmission signal, while a portion is split and sent to the remote control small-loop receiving unit. The small-loop receiving unit demodulates and recovers the small-loop remote control data, then compares it bit-by-bit with the original payload power-on command.If the comparison results are completely consistent, the ZYNQ main control module reports the comparison success to the host computer, indicating that the data generated by the device's internal remote control transmission link is consistent with the original command. If the comparison finds a single bit mismatch in the command text field, the ZYNQ main control module can report a comparison failure and mark the error location. The operator can then use this information to stop or resend the command, preventing erroneous commands from entering the uplink.

[0028] In some examples, the measurement and control demodulation processing unit includes a pseudo-code acquisition subunit, a pseudo-code tracking subunit, and a carrier recovery subunit; The pseudocode acquisition subunit is used to perform fast Fourier transform on the zero intermediate frequency in-phase quadrature signal and the local pseudocode sequence respectively, multiply the frequency domain data of the transformed received signal with the frequency domain data of the transformed local pseudocode, and perform inverse fast Fourier transform on the frequency domain multiplication result to obtain the correlation result. Then, based on the threshold decision, it outputs the pseudocode phase estimate and the carrier frequency offset estimate. The pseudocode tracking subunit is used to track and correct the pseudocode phase estimate based on the delay-locked loop; The carrier recovery subunit is used to perform carrier recovery based on the Costas phase-locked loop and the carrier frequency offset estimate, so as to provide a synchronization basis for the despreading, bit synchronization, frame synchronization and decoding processes.

[0029] For example, the telemetry, tracking, and command (TT&C) demodulation processing unit receives the zero-IF in-phase quadrature signal obtained after digital down-conversion. The pseudo-code acquisition subunit first selects a local pseudo-code sequence based on the mission parameters. This local pseudo-code sequence can be Gold code or other pseudo-random sequences suitable for the satellite's TT&C system. The pseudo-code acquisition subunit buffers a segment of the received signal as a received signal data block and simultaneously generates a local pseudo-code data block with a length matching this data block. Subsequently, a Fast Fourier Transform (FFT) is performed on the received signal data block to obtain the received signal frequency domain data; a FFT is also performed on the local pseudo-code data block to obtain the local pseudo-code frequency domain data. After completing the frequency domain transformation, the pseudo-code acquisition subunit performs a frequency domain multiplication of the received signal frequency domain data and the local pseudo-code frequency domain data. To implement correlation operations, in actual processing, the local pseudo-code frequency domain data can be conjugated before participating in the frequency domain multiplication; the specific implementation can be determined based on the internal correlator structure of the FPGA. After the frequency domain multiplication, an Inverse Fast Fourier Transform (FFT) is performed on the result to obtain the correlation result. Each sampling position in the correlation result corresponds to the correlation strength of a pseudo-code phase assumption. The pseudocode acquisition subunit searches for peak values ​​in the correlation results and compares these peak values ​​with a preset threshold. If the peak value exceeds the threshold, acquisition is considered successful, and the location of the peak value is determined as the pseudocode phase estimate. To estimate the carrier frequency offset, the pseudocode acquisition subunit can set multiple frequency offset search points within a preset frequency offset range. For example, in missions with strong satellite relative motion, multiple frequency offset assumptions can be set around the nominal frequency. For each frequency offset assumption, the received signal is first compensated for the corresponding frequency, and then the above frequency domain correlation process is executed to obtain the correlation peak value under that frequency offset assumption. After comparing the correlation peak values ​​corresponding to each frequency offset search point, the frequency offset corresponding to the largest correlation peak value is taken as the carrier frequency offset estimate. If the correlation peak values ​​of multiple frequency offset search points are close, the frequency offset estimate from the previous moment, satellite orbit prediction information, or loop locking status can also be combined for selection. After successful pseudocode acquisition, the pseudocode phase estimate is sent to the pseudocode tracking subunit. The pseudocode tracking subunit initializes the local pseudocode numerically controlled oscillator based on this estimate, causing the local pseudocode to start running from near the acquisition position. Subsequently, the pseudocode tracking subunit generates early code, local punctual code, and late code, and correlates them with the received signal. The early and late codes typically have the same magnitude but opposite time offset relative to the punctual code. The pseudocode tracking subunit calculates the pseudocode phase error based on the difference between the early and late code correlation results and inputs this error into the loop filter. The loop filter outputs a control variable to adjust the frequency or phase of the pseudocode numerically controlled oscillator, gradually maintaining the local pseudocode at the optimal alignment position with the received pseudocode. After receiving the estimated carrier frequency offset, the carrier recovery subunit initializes the local carrier numerically controlled oscillator, bringing its frequency close to the received signal carrier frequency. Then, the Costas phase-locked loop calculates the carrier phase error based on the in-phase and quadrature components and adjusts the local carrier numerically controlled oscillator via the loop filter.If the received signal has a residual Doppler frequency offset, the Costas phase-locked loop will gradually correct this residual frequency offset, reducing the phase rotation speed of the received signal. After carrier recovery is completed, despreading can be performed under a stable phase reference, bit synchronization can more accurately determine the symbol sampling time, frame synchronization can more reliably identify telemetry frame boundaries, and decoding can achieve a lower bit error rate.

[0030] Accordingly, this application also provides a measurement, control, and tracking method, see reference. Figure 6 This is a schematic flowchart of a measurement and control tracking method provided in an embodiment of this application. The method may specifically include steps S110 to S170.

[0031] S110, receives satellite downlink radio frequency signals, performs gain control and analog-to-digital conversion on the satellite downlink radio frequency signals, and obtains digital received signals; S120, perform digital down-conversion and Doppler frequency offset compensation on the digitized received signal to obtain a zero intermediate frequency in-phase quadrature signal; S130, the zero intermediate frequency in-phase quadrature signal is synchronously distributed to the measurement and control demodulation processing flow and the tracking processing flow; S140, in the telemetry and demodulation process, based on the zero intermediate frequency in-phase quadrature signal, spread spectrum acquisition, pseudo-code tracking, carrier recovery, despreading, bit synchronization, frame synchronization and decoding are performed sequentially to obtain telemetry data; S150, in the tracking processing flow, the sum path signal and the difference path signal are synchronized based on the zero intermediate frequency in-phase quadrature signal, demodulated to obtain azimuth error voltage and elevation error voltage, and the azimuth error voltage and the elevation error voltage are output to the servo system to guide the antenna to track the satellite; S160: Receives remote control commands from the host computer, encodes, spreads, and modulates the remote control commands to generate a remote control transmission signal, and outputs the remote control transmission signal. S170, based on the telemetry data, the remote control command, the device status and the tracking error data, the measurement and control tracking status is monitored, and feedback information for adjusting the tracking parameters is provided to the tracking processing flow according to the telemetry data.

[0032] For example, after the integrated telemetry, tracking, and command (TT&C) system is powered on, the power supply module first converts and protects the input power, providing the necessary voltage for the ZYNQ main control module, FPGA signal processing module, RF transceiver module, clock management module, and interface module. After startup, the clock management module outputs a stable clock and distributes it to the RF transceiver module, FPGA signal processing module, and ZYNQ main control module. Subsequently, the ZYNQ main control module loads the system software, completes firmware loading and register initialization for the FPGA signal processing module, and configures the TT&C and tracking operating parameters according to the current task, including receiving frequency, transmitting frequency, pseudocode type, code rate, modulation method, loop bandwidth, telemetry frame format, tracking error output format, and interface operating mode. In the receiving link, the satellite downlink RF signal enters the RF transceiver module via the RF interface. The RF transceiver module performs gain control on the input signal to adapt its amplitude to the dynamic range of the analog-to-digital converter and converts the analog RF or intermediate frequency signal into a digital received signal. After the digitized received signal enters the FPGA signal processing module, it is first frequency-converted and Doppler frequency offset compensated by the digital down-conversion unit to obtain a zero-IF in-phase quadrature signal. The local frequency, filter bandwidth, and decimation parameters of the digital down-conversion unit can be set by the ZYNQ main control module according to the task configuration or operating status. After obtaining the zero-IF in-phase quadrature signal, the FPGA signal processing module internally synchronously distributes it to the telemetry, monitoring, and demodulation processing unit and the tracking processing unit. The telemetry, monitoring, and demodulation processing unit performs spread spectrum acquisition on the signal to determine the approximate position of the pseudocode phase and carrier frequency offset; after successful acquisition, it further maintains signal synchronization through pseudocode tracking and carrier recovery; subsequently, it performs despreading, bit synchronization, frame synchronization, and decoding processing to recover the satellite telemetry data. The recovered telemetry data is transmitted to the ZYNQ main control module through a high-speed data channel. The ZYNQ main control module can store it in its local storage unit or send it to the back-end telemetry and monitoring center or host computer software through a network interface. At the same time, the tracking processing unit performs synchronization processing on the sum and difference signals based on the same zero-IF in-phase quadrature signal. The sum-path signal is used to establish a stable pseudocode and carrier reference, while the difference-path signal is used to extract error information related to antenna pointing deviation. The tracking processing unit demodulates the error information into azimuth error voltage and elevation error voltage, and outputs them to the servo system through the interface module. The servo system drives the antenna's azimuth and elevation axes to move according to the error voltage, gradually bringing the antenna pointing closer to the satellite's direction. The ZYNQ main control module simultaneously reads the tracking error data and, in conjunction with telemetry data, lock status, and equipment status, determines the current tracking quality. In the remote control link, the host computer or telemetry and control center sends remote control commands to the ZYNQ main control module. After performing task matching and transmission control on the commands, the ZYNQ main control module hands the remote control commands over to the FPGA signal processing module. The FPGA encodes, spreads, and modulates the remote control commands to generate a remote control transmission signal, which is then sent to the RF transceiver module.The RF transceiver module performs RF conversion and outputs the remote control transmission signal, enabling the remote control command to be transmitted to the satellite via the uplink. The transmission time, transmission parameters, equipment status, and current tracking error throughout the entire remote control transmission process can be uniformly recorded by ZYNQ, facilitating subsequent traceability and status analysis. During operation, the ZYNQ main control module continuously monitors telemetry data, remote control commands, equipment status, and tracking error data. If telemetry data indicates a deterioration in link quality, such as increased bit error rate, unstable frame synchronization, or abnormal carrier lock state, the ZYNQ main control module can provide feedback information to the tracking processing unit, allowing the tracking processing unit to adjust the tracking parameters. If the tracking error data remains consistently large while the telemetry data synchronization deteriorates, the system can determine that antenna pointing deviation is likely the primary cause; if the tracking error data is normal but the telemetry data deteriorates, it may be due to link interference, changes in satellite transmission power, or channel fading. By uniformly acquiring and correlating these data within the same system, this solution improves fault diagnosis efficiency and operational stability.

[0033] In some examples, the step of performing spread spectrum acquisition based on the zero-IF in-phase quadrature signal in the measurement and control demodulation process includes: Fast Fourier transform is performed on the zero intermediate frequency in-phase quadrature signal and the local pseudocode sequence to obtain the received signal frequency domain data and the local pseudocode frequency domain data, respectively. The received signal frequency domain data is multiplied with the local pseudocode frequency domain data in the frequency domain to obtain frequency domain correlation data; Perform an inverse fast Fourier transform on the frequency domain correlation data to obtain the correlation results; Based on the aforementioned results, a threshold decision is made, and the pseudocode phase estimate and carrier frequency offset estimate are output. The pseudocode phase estimate is used for pseudocode tracking, and the carrier frequency offset estimate is used for carrier recovery.

[0034] In some examples, the execution of pseudocode tracking and carrier recovery in the telemetry and demodulation process includes: The pseudocode phase is tracked and corrected based on a delay-locked loop, wherein the delay-locked loop extracts the pseudocode phase error by the difference between the early code correlation result and the late code correlation result, and adjusts the pseudocode numerically controlled oscillator based on the pseudocode phase error. Carrier recovery is performed based on Costas phase-locked loop, and frequency-locked loop is combined to assist in carrier frequency offset acquisition, so as to dynamically compensate for Doppler frequency offset and Doppler rate of change in satellite downlink radio frequency signal; The pseudocode tracking results and carrier recovery results are used as the synchronization basis for the despreading, bit synchronization, frame synchronization and decoding processes.

[0035] In some examples, the step of performing synchronization processing of the sum-path signal and the difference-path signal based on the zero-IF in-phase quadrature signal in the tracking process, and demodulating to obtain the azimuth error voltage and the pitch error voltage, includes: Pseudocode recovery and carrier recovery are performed based on the sum-path signal, and the automatic gain control voltage corresponding to the sum-path signal is obtained; The differential signal is normalized based on the automatic gain control voltage to reduce the impact of the gain difference between the sum and difference channels on the error demodulation. The differential signal after amplitude normalization is subjected to phase shifting, integration and detection processing to obtain the azimuth error voltage and the elevation error voltage. Based on the telemetry and control status information corresponding to the telemetry data, at least one of the following parameters is adjusted: tracking loop bandwidth, tracking accuracy threshold, or error voltage output parameter.

[0036] In some examples, it also includes: After generating the remote control transmission signal, a portion of the remote control transmission signal is split into a small loop detection signal; The small loop detection signal is spread spectrum demodulated to extract the small loop remote control data; The remote control data of the small ring is compared bit by bit with the original remote control command issued by the host computer to obtain the remote control small ring comparison result. The comparison range of the bitwise comparison includes the pre-complementary sequence, the instruction text, and the post-complementary sequence, and the correctness of the transmission of the remote control instruction is determined based on the comparison result of the remote control ring.

[0037] In some cases, considering the slow unidirectional drift of azimuth or pitch error voltage even when the device is in a stable tracking state, the telemetry data frame synchronization is stable, the carrier lock state is stable, the automatic gain control voltage corresponding to the sum path signal changes very little, and the servo system angular velocity is also low. From the perspective of a normal link state, the system appears to be in a normal tracking state. However, in miniaturized integrated telemetry and tracking equipment, the RF devices, amplification paths, filtering paths, analog-to-digital conversion paths, and on-board wiring of the sum and difference paths are not entirely consistent. Different areas within the equipment are also affected differently by heat sources such as FPGAs, power modules, and RF transceiver chips, leading to asynchronous drift in the gain, phase delay, or zero-position voltage of the sum and difference paths. This drift is interpreted by the error voltage demodulation subunit as antenna pointing deviation, thus forming a false angle error. Based on this, in some examples, the synchronization processing of the sum and difference paths based on the zero-IF in-phase quadrature signal in the tracking process, and the demodulation to obtain the azimuth and pitch error voltages, includes: When the frame synchronization state of the telemetry data is stable, the carrier lock state is stable, the change in the automatic gain control voltage corresponding to the path signal is less than the preset gain change threshold, and the angular velocity of the servo system is less than the preset angular velocity threshold, it is determined that the current state is in a steady-state tracking window. Within the steady-state tracking window, acquire device temperature data, radio frequency operating frequency, automatic gain control voltage, and drift characteristics of azimuth error voltage and pitch error voltage; When the azimuth error voltage or the pitch error voltage exhibits a slow unidirectional drift, and the demodulation quality corresponding to the telemetry data does not decrease synchronously, the bias correction amount corresponding to the current device temperature, RF operating frequency, and automatic gain control voltage is determined based on the preset sum and difference channel bias fingerprint table. The azimuth error voltage or the pitch error voltage is corrected based on the bias correction amount to reduce the false angle error caused by the asynchronous thermal drift between the sum path channel and the difference path channel.

[0038] For example, the system first needs to determine whether it has entered the steady-state tracking window. The ZYNQ main control module can periodically read the frame synchronization status, carrier lock status, automatic gain control voltage, servo system feedback angular velocity, azimuth error voltage, and elevation error voltage of the telemetry data. If, within several consecutive observation periods, frame synchronization remains effective, carrier lock is not lost, the change in automatic gain control voltage is less than a preset gain change threshold, and the servo system angular velocity is less than a preset angular velocity threshold, then it is determined that it is currently in the steady-state tracking window. The significance of this window is to exclude situations such as rapid satellite movement, significant antenna adjustments, and severe link fading that could actually cause changes in error voltage, thereby providing relatively stable observation conditions for identifying thermal drift. After entering the steady-state tracking window, the ZYNQ main control module acquires equipment temperature data, RF operating frequency, automatic gain control voltage, and drift characteristics of azimuth error voltage and elevation error voltage. Equipment temperature data can come from temperature sensors located near the RF module, FPGA, power module, or inside the chassis; the RF operating frequency is determined by the current measurement and control task configuration; the automatic gain control voltage comes from the gain control state of the sum and difference signals; error voltage drift characteristics can be calculated using a sliding window, such as calculating the slope of the mean error voltage change, drift direction duration, drift amplitude, and short-time variance. If the mean error voltage changes slowly in the same direction within multiple consecutive windows, and the short-time variance is small, it indicates that it is more consistent with the slow bias pattern of thermal drift than random jumps caused by external interference. Subsequently, the system determines whether the demodulation quality corresponding to the telemetry data has decreased synchronously. Demodulation quality can include bit error rate, frame synchronization hold rate, carrier lock margin, despread signal-to-noise ratio, or telemetry frame verification pass rate. If the error voltage drifts slowly in one direction, but these telemetry demodulation quality indicators do not deteriorate synchronously, the ZYNQ main control module looks up the bias correction amount corresponding to the current equipment temperature, RF operating frequency, and automatic gain control voltage from the preset sum and difference channel bias fingerprint table. If the current parameters fall within the fingerprint table record points, interpolation can be used to determine the correction amount. For example, when operating between two calibration points at temperatures of 35 degrees Celsius and 45 degrees Celsius, the corresponding offset correction amount can be calculated based on the ratio of the current temperature to the two calibration points. Finally, the ZYNQ main control module sends the offset correction amount to the error voltage demodulation processing logic in the FPGA. Before outputting the azimuth and pitch error voltages, the FPGA first performs offset subtraction or offset compensation on the original error voltages, and then outputs the corrected error voltages to the servo system. Different directions can be corrected separately. For example, if only the azimuth error voltage experiences thermal drift, only the azimuth error voltage is corrected; if only the pitch error voltage experiences thermal drift, only the pitch error voltage is corrected; if both drift exist, corrections are performed separately according to the corresponding fingerprint table entries.

[0039] In some cases, considering that in dual-channel tracking, if the differential path is affected by local interference, poor interface contact, differential path amplification link compression, or an abnormal differential path input, the system may output incorrect azimuth or elevation error voltages. At this time, the sum path signal remains normal, and the telemetry demodulation quality may also be normal, so the system will not trigger a conventional link lockout alarm. However, the servo system may continuously adjust the antenna based on the abnormal differential path error voltage, ultimately pulling the antenna away from its optimal pointing position. Therefore, in some examples, the synchronization processing of the sum and differential path signals based on the zero-IF in-phase quadrature signal in the tracking process, and the demodulation to obtain the azimuth and elevation error voltages, includes: The demodulation quality corresponding to the telemetry data, the automatic gain control voltage corresponding to the sum path signal, the energy characteristics of the differential path signal, the azimuth error voltage, the pitch error voltage, and the servo system feedback angular velocity are obtained. If the azimuth error voltage or the pitch error voltage suddenly changes, saturates, has a long-term unilateral bias, or does not match the servo system feedback angular velocity when the demodulation quality is stable and the change in the automatic gain control voltage is less than the preset gain change threshold, then it is determined that the corresponding differential signal is at risk of contamination. If it is determined that the corresponding differential signal has a risk of contamination, the error voltages in the azimuth error voltage or the pitch error voltage that correspond to the differential signal with the risk of contamination are subjected to amplitude limiting, weight reduction, or short-term holding. The antenna is guided to track the satellite based on the processed azimuth error voltage and elevation error voltage.

[0040] For example, the ZYNQ main control module periodically acquires the demodulation quality corresponding to the telemetry data, the automatic gain control voltage corresponding to the sum path signal, the energy characteristics of the differential path signal, the azimuth error voltage, the elevation error voltage, and the servo system feedback angular velocity. The demodulation quality can be represented by the bit error rate, frame synchronization continuity, carrier lock state, and the quality of the despread signal; the differential path signal energy characteristics can be represented by the mean square value, peak-to-average power ratio, short-time energy mutation rate, or saturation sampling ratio of the differential path in-phase quadrature data; the servo system feedback angular velocity can be obtained from the azimuth and elevation axis velocities returned by the servo system. The system first determines whether the demodulation quality is stable and whether the change in the sum path automatic gain control voltage is less than a preset threshold. Only when the sum path link is relatively stable is the differential path pollution risk further assessed. This avoids misjudging actual link fading or significant antenna deviation as differential path pollution. Subsequently, the system performs abnormality detection on the azimuth error voltage and elevation error voltage respectively. Sudden changes can be identified by whether the difference in error voltage between adjacent observation periods exceeds a threshold; saturation can be identified by whether the error voltage remains near the upper or lower limit of the output for an extended period; long-term unilateral bias can be identified by the mean error voltage continuously deviating from zero within multiple windows; mismatch with the servo feedback angular velocity can be identified by the relationship between the direction of error voltage change, the direction of servo angular velocity, and the trend of error reduction. Upon determining that a certain differential signal poses a risk of contamination, the system does not immediately stop tracking but instead performs amplitude limiting, weight reduction, or short-term hold processing on the error voltage corresponding to that differential signal. Amplitude limiting restricts the abnormal error voltage within a safe range, preventing it from driving the servo system to perform excessive actions; weight reduction reduces the impact of this error voltage on the servo control input, making the servo system rely more on the normal error voltage in another direction, the predicted orbital angular velocity, or the most recent reliable error estimate; short-term hold temporarily holds the error voltage in that direction at the most recent reliable value, waiting for the differential signal to recover. If only the azimuth error path is at risk of contamination, then only the azimuth error voltage is processed, while the pitch error voltage continues to be output normally; if only the pitch error path is at risk of contamination, then only the pitch error voltage is processed, while the azimuth error voltage continues to be output normally.

[0041] In some cases, considering that multi-target telemetry and control typically distinguishes different targets using different pseudo-code sequences, theoretically, different pseudo-codes should have low cross-correlation. However, in actual tasks, pseudo-code cross-correlation is not the only influencing factor. The signal strength of different targets may vary greatly, the Doppler frequency offset may differ, and the relative positions of the code phases may also change dynamically. When the correlation sidelobe or cross-correlation component of a strong signal target falls into the acquisition window of a weak signal target, an abnormal correlation peak may be formed in the weak target acquisition correlation map. This scheme refers to this abnormal correlation peak as pseudo-code cross-correlation trailing. Based on this, in some examples, when the telemetry and control demodulation processing flow is used for simultaneous telemetry and control tracking of multiple targets, the method further includes: Record the acquisition correlation diagram, code phase estimate, carrier frequency offset estimate, demodulation bit error rate, and sum signal strength for each target respectively; Based on the code phase relationship, carrier frequency offset relationship, and difference in signal strength between different targets, it is determined whether the abnormal correlation peak in the acquisition correlation diagram of the weak signal target moves synchronously with the code phase change of the strong signal target. If the abnormal correlation peak moves synchronously with the code phase change of the strong signal target, and the relative distance between the abnormal correlation peak and the true correlation peak of the weak signal target remains stable over multiple observation periods, it is determined that the weak signal target has a pseudo-code cross-correlation trailing. If it is determined that the weak signal target has pseudocode cross-correlation trailing, a backup pseudocode with a pseudocode cross-correlation risk lower than a preset risk threshold with the strong signal target is selected from the preset pseudocode set for the weak signal target, or a suppression weight is set on the position of the abnormal correlation peak in the capture threshold decision of the weak signal target.

[0042] It is understandable that a strong target may be completely normal, and a weak target may not necessarily be completely lost, but rather exhibit repeated acquisition, slight deviations in pseudocode tracking, occasional increases in the bit error rate, or unstable correlation peak decisions. Conventional designs often select code groups based solely on the theoretical cross-correlation index of the pseudocode sequence. However, a low theoretical cross-correlation does not guarantee the absence of ghosting under actual power differences, frequency deviations, and code phase arrangements. Especially when the signal power of the strong target is much higher than that of the weak target, the correlation sidelobes of the strong target may exceed the noise background near the true peak of the weak target, causing misjudgments in the weak target acquisition logic.

[0043] For example, the FPGA signal processing module performs acquisition, tracking, and demodulation on each target, while the ZYNQ main control module records the acquisition correlation map, code phase estimate, carrier frequency offset estimate, demodulation bit error rate, and sum signal strength for each target. The acquisition correlation map represents the correlation strength distribution at different code phase positions; the code phase estimate represents the current pseudocode alignment position of the target signal; the carrier frequency offset estimate represents the frequency offset of the target relative to the local carrier; and the sum signal strength is used to distinguish between strong and weak signal targets. The system first identifies strong and weak signal targets based on the sum signal strength and demodulation quality. For example, targets with sum signal strength above average and stable demodulation are considered strong signal targets, while targets with low sum signal strength and poor acquisition or tracking stability are considered weak signal targets. Subsequently, the ZYNQ main control module monitors abnormal correlation peaks in the acquisition correlation map of weak signal targets over multiple observation periods. Abnormal correlation peaks can be larger secondary peaks other than the true correlation peak, or local peaks close to the true peak but causing a skewed peak shape. Next, the system compares the relationship between the abnormal correlation peaks and the code phase changes of strong signal targets. If the abnormal peak in the weak signal target acquisition correlation graph moves in the same or predictable way when the code phase of the strong signal target changes, it indicates that the abnormal peak may originate from the cross-correlation trail of the pseudo-code of the strong target. Further, the system determines whether the relative distance between the abnormal peak and the true peak of the weak target remains stable over multiple observation periods. If the distance is stable, it indicates that the abnormal peak is not random noise, but is generated by some stable inter-code relationship. The system can also combine the carrier frequency offset relationship to determine whether the abnormal peak matches the frequency offset of the strong signal target, further improving the reliability of the judgment. After determining that the weak signal target has a pseudo-code cross-correlation trail, the system can adopt two processing methods. The first method is to select a backup pseudo-code for the weak signal target from a preset pseudo-code set. The ZYNQ main control module selects a backup pseudo-code with a cross-correlation risk lower than a preset risk threshold based on the pseudo-code currently used by the strong signal target, the power difference between each target, the current code phase relationship, and the carrier frequency offset relationship, and assigns this backup pseudo-code to the weak signal target. The second type involves setting a suppression weight at the location of the abnormal correlation peak when the pseudocode cannot be changed immediately for weak signal targets. This reduces the influence of the location when calculating the capture threshold decision or pseudocode tracking error, thus avoiding the interference of the trailing peak with the decision of the true peak.

[0044] In some cases, ideally, the azimuth error voltage should primarily correspond to the antenna azimuth axis deviation, and the elevation error voltage should primarily correspond to the antenna elevation axis deviation. However, in practical portable deployments, antennas may be mounted on vehicles, temporary supports, uneven ground, or slightly tilted platforms, causing a deflection between the antenna coordinate system and the theoretical azimuth and elevation coordinate systems. In this case, servo corrections in the azimuth direction may cause changes in the elevation error voltage, and servo corrections in the elevation direction may also cause changes in the azimuth error voltage, resulting in error voltage coordinate coupling. Therefore, in some examples, outputting the azimuth error voltage and the elevation error voltage to the servo system to guide the antenna in tracking the satellite includes: After completing the initial acquisition of satellite signals and entering a stable tracking state, record the azimuth error voltage, elevation error voltage, azimuth angle fed back by the servo system, elevation angle fed back by the servo system, and demodulation quality corresponding to the telemetry data within a preset time period. Based on the correspondence between the small azimuth correction action generated by the servo system during the tracking process and the pitch error voltage change, the coupling coefficient of azimuth correction to pitch error voltage is determined. Based on the correspondence between the small pitch correction action generated by the servo system during the tracking process and the change in the azimuth error voltage, the coupling coefficient of pitch correction to the azimuth error voltage is determined. Based on the coupling coefficient of the azimuth correction to the pitch error voltage and the coupling coefficient of the pitch correction to the azimuth error voltage, an error voltage coordinate correction matrix is ​​generated; The azimuth error voltage and the pitch error voltage are corrected based on the error voltage coordinate correction matrix, and the corrected azimuth error voltage and pitch error voltage are output to the servo system.

[0045] For example, after the system completes initial satellite signal acquisition and enters a stable tracking state, it begins recording the azimuth error voltage, elevation error voltage, azimuth angle fed back by the servo system, elevation angle fed back by the servo system, and demodulation quality corresponding to telemetry data within a preset time period. A stable tracking state can be determined by conditions such as stable telemetry frame synchronization, stable carrier lock, a bit error rate below a threshold, and servo action amplitude within a small range. Only by estimating the coupling relationship under stable conditions can the risk of misjudging real link fading or external disturbances as coordinate coupling be reduced. The system calculates small-amplitude correction actions based on the azimuth and elevation angles fed back by the servo system. For example, if a measurable small change in azimuth occurs within a certain time period, while the change in elevation angle is very small, this time period can be used as the dominant window for azimuth correction. Within this window, the system observes whether the elevation error voltage changes regularly with azimuth correction. If a stable proportional relationship exists between the elevation error voltage and the azimuth angle change, the coupling coefficient of azimuth correction on the elevation error voltage is determined. Similarly, when the pitch angle changes slightly within a certain time period while the azimuth angle changes very little, this time period can be used as the dominant window for pitch correction. The system observes whether the azimuth error voltage changes regularly with pitch correction and determines the coupling coefficient between pitch correction and the azimuth error voltage. After obtaining the two coupling coefficients, the ZYNQ main control module generates an error voltage coordinate correction matrix. This correction matrix describes the correspondence between the original azimuth error voltage, the original pitch error voltage, and the corrected azimuth error voltage and corrected pitch error voltage. Before outputting the error voltage, the error voltage demodulation subunit can use this correction matrix to correct the original error voltage, so that the corrected azimuth error voltage mainly corresponds to the azimuth axis deviation, and the corrected pitch error voltage mainly corresponds to the pitch axis deviation. If the installation platform status changes during operation, such as changes in the attitude of the vehicle platform or deformation of the support due to wind, the system can also update the coupling coefficients in subsequent windows that meet the stability conditions.

[0046] In some cases, considering the potential impact of providing feedback information for adjusting tracking parameters based on telemetry data to the tracking processing flow: the telemetry data is not used to adjust tracking parameters immediately upon generation; it undergoes processes such as FPGA demodulation, buffering, transmission, ZYNQ processing, and feedback command issuance, resulting in feedback delay. In low-dynamic scenarios, this delay may have a smaller impact; however, in high-dynamic scenarios such as satellite transits, rapid signal fading, rapid antenna adjustments, or multi-target switching, the telemetry data reflects the link state at a past moment, while the current tracking processing faces a new signal state. Without considering time alignment, the system might use outdated telemetry quality to adjust the current tracking parameters, causing misalignment instead of optimized feedback. Therefore, in some examples, providing feedback information for adjusting tracking parameters based on the telemetry data includes: When generating the telemetry data, the tracking error data, and the tracking processing status data, time tags generated based on the same clock reference are attached to the telemetry data, the tracking error data, and the tracking processing status data, respectively. Before generating feedback information for adjusting tracking parameters based on the telemetry data, the time stamp of the telemetry data is matched with the time stamp of the current tracking error data to determine the telemetry feedback delay. If the telemetry feedback delay is less than a preset delay threshold, feedback information for adjusting tracking parameters is directly generated based on the telemetry data. When the telemetry feedback delay is greater than or equal to the preset delay threshold, the link status at the current moment is predicted based on the changing trend of the tracking error data, the servo system feedback angular velocity, and multiple historical telemetry quality samples. Feedback information for adjusting tracking parameters is then generated based on the predicted link status at the current moment.

[0047] For example, when generating telemetry data, tracking error data, and tracking processing status data, the FPGA signal processing module attaches time stamps based on the same clock reference. The time stamps for the telemetry data correspond to the sampling time at which decoding or frame synchronization is completed; the time stamps for the tracking error data correspond to the generation times of the azimuth error voltage and elevation error voltage; and the time stamps for the tracking processing status data correspond to the generation times of the pseudocode tracking status, carrier recovery status, or error voltage output status. Because these time stamps come from the same clock reference, the ZYNQ master module can accurately compare the time relationships between different data. Before the ZYNQ master module prepares to generate tracking parameter adjustment information based on the telemetry data, it first matches the time stamps of the telemetry data with the time stamps of the current tracking error data and calculates the telemetry feedback delay. If this delay is less than a preset delay threshold, it indicates that the telemetry data can still represent the current link status, and the ZYNQ master module can directly use the telemetry data to adjust the tracking parameters. For example, when the telemetry bit error rate increases and the current azimuth error voltage also shows a deviation trend, the tracking loop bandwidth or error voltage output smoothing parameter can be adjusted appropriately. If the telemetry feedback delay is greater than or equal to a preset delay threshold, it indicates that the telemetry data may have expired. In this case, the ZYNQ main control module does not directly adjust the tracking parameters based on this telemetry data. Instead, it combines the current tracking error data change trend, the servo system feedback angular velocity, and multiple historical telemetry quality samples to predict the current link status. The tracking error data change trend reflects whether the antenna pointing is improving or deteriorating; the servo system feedback angular velocity reflects whether the antenna has already performed a correction action; and historical telemetry quality samples reflect the continuous trend of link quality changes. If the historical telemetry quality first decreases and then recovers, while the current error voltage is also decreasing, it can be predicted that the current link status has recovered, and tracking adjustments should not be increased based on the old, low-quality telemetry data. If the historical telemetry quality continues to decrease, while the current error voltage is still increasing, it can be predicted that the current link is still in a deteriorating state, requiring parameter adjustments.

[0048] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0049] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An integrated measurement, control, and tracking system, characterized in that, include: ZYNQ main control module, FPGA signal processing module, RF transceiver module and interface module; The radio frequency transceiver module is used to obtain a digital received signal based on the received satellite downlink radio frequency signal, and send the digital received signal to the FPGA signal processing module; The FPGA signal processing module is used to obtain zero-IF in-phase quadrature signals based on the digital received signals, and synchronously distribute the zero-IF in-phase quadrature signals to the measurement and control demodulation processing unit and the tracking processing unit. The measurement and control demodulation processing unit is used to obtain telemetry data based on the zero intermediate frequency in-phase quadrature signal; The tracking processing unit is used to demodulate the zero-IF in-phase quadrature signal to obtain the azimuth error voltage and the elevation error voltage, and outputs the azimuth error voltage and the elevation error voltage to the servo system through the interface module to guide the antenna to track the satellite; The FPGA signal processing module is also used to encode, spread, and modulate the remote control commands issued by the host computer, generate a remote control transmission signal, and output the remote control transmission signal through the radio frequency transceiver module. The ZYNQ main control module is connected to the FPGA signal processing module and is used to configure the measurement and control tracking working parameters, perform data interaction and status monitoring on the telemetry data, the remote control command, the equipment status and tracking error data, and provide feedback information to the tracking processing unit for adjusting the tracking parameters based on the telemetry data.

2. The system as described in claim 1, characterized in that, Also includes: The clock management module provides a synchronization clock to the ZYNQ main control module, the FPGA signal processing module, and the RF transceiver module, so that the measurement and control demodulation process, the remote control modulation process, and the tracking process are executed under the same clock reference.

3. The system as described in claim 1, characterized in that, The tracking processing unit includes a sum processing subunit, a difference processing subunit, an amplitude normalization subunit, and an error voltage demodulation subunit. The sum-path processing subunit is used to perform pseudocode recovery and carrier recovery based on the sum-path signal, and to provide signal synchronization results to the measurement and control demodulation processing unit. The differential path processing subunit is used to receive differential path signals; The amplitude normalization subunit is used to perform amplitude normalization processing on the differential signal based on the automatic gain control voltage corresponding to the sum signal, so as to reduce the impact of the gain difference between the sum channel and the differential channel on the error voltage demodulation. The error voltage demodulation subunit is used to perform phase shifting, integration and detection processing on the amplitude-normalized differential signal to obtain the azimuth error voltage and the elevation error voltage.

4. The system as described in claim 1, characterized in that, The FPGA signal processing module also includes a remote control loop receiving unit; The remote control loop receiving unit is used to receive the loop detection signal obtained by splitting the remote control transmission signal, perform spread spectrum demodulation processing on the loop detection signal, extract the loop remote control data, and compare the loop remote control data with the original remote control command sent by the host computer bit by bit to obtain the remote control loop comparison result. The comparison range of the bitwise comparison includes the pre-complementary sequence, the instruction text, and the post-complementary sequence. The ZYNQ main control module is used to receive and report the comparison results of the remote control ring.

5. The system as described in claim 1, characterized in that, The measurement and control demodulation processing unit includes a pseudo-code acquisition subunit, a pseudo-code tracking subunit, and a carrier recovery subunit; The pseudocode acquisition subunit is used to perform fast Fourier transform on the zero intermediate frequency in-phase quadrature signal and the local pseudocode sequence respectively, multiply the frequency domain data of the transformed received signal with the frequency domain data of the transformed local pseudocode, and perform inverse fast Fourier transform on the frequency domain multiplication result to obtain the correlation result. Then, based on the threshold decision, it outputs the pseudocode phase estimate and the carrier frequency offset estimate. The pseudocode tracking subunit is used to track and correct the pseudocode phase estimate based on the delay-locked loop; The carrier recovery subunit is used to perform carrier recovery based on the Costas phase-locked loop and the carrier frequency offset estimate, so as to provide a synchronization basis for the despreading, bit synchronization, frame synchronization and decoding processes.

6. A measurement, control, and tracking method, characterized in that, For a system as described in any one of claims 1 to 5, the method comprises: Receive satellite downlink radio frequency signals, perform gain control and analog-to-digital conversion on the satellite downlink radio frequency signals to obtain digital received signals; The digitized received signal is digitally down-converted and Doppler frequency offset compensated to obtain a zero intermediate frequency in-phase quadrature signal; The zero-IF in-phase quadrature signal is synchronously distributed to the measurement and control demodulation processing flow and the tracking processing flow; In the telemetry and demodulation process, based on the zero-IF in-phase quadrature signal, spread spectrum acquisition, pseudo-code tracking, carrier recovery, despreading, bit synchronization, frame synchronization and decoding are performed sequentially to obtain telemetry data; In the tracking process, the sum and difference signals are synchronized based on the zero intermediate frequency in-phase quadrature signal, demodulated to obtain azimuth error voltage and elevation error voltage, and the azimuth error voltage and elevation error voltage are output to the servo system to guide the antenna to track the satellite. The system receives remote control commands from a host computer, encodes, spreads, and modulates the remote control commands to generate a remote control transmission signal, and outputs the remote control transmission signal. Based on the telemetry data, the remote control command, the device status, and the tracking error data, the system monitors the tracking status and provides feedback information to the tracking processing flow for adjusting tracking parameters based on the telemetry data.

7. The method as described in claim 6, characterized in that, The step of performing spread spectrum acquisition based on the zero-IF in-phase quadrature signal in the measurement and control demodulation process includes: Fast Fourier transform is performed on the zero intermediate frequency in-phase quadrature signal and the local pseudocode sequence to obtain the received signal frequency domain data and the local pseudocode frequency domain data, respectively. The received signal frequency domain data is multiplied with the local pseudocode frequency domain data in the frequency domain to obtain frequency domain correlation data; Perform an inverse fast Fourier transform on the frequency domain correlation data to obtain the correlation results; Based on the aforementioned results, a threshold decision is made, and the pseudocode phase estimate and carrier frequency offset estimate are output. The pseudocode phase estimate is used for pseudocode tracking, and the carrier frequency offset estimate is used for carrier recovery.

8. The method as described in claim 6, characterized in that, The pseudocode tracking and carrier recovery performed in the measurement and control demodulation process include: The pseudocode phase is tracked and corrected based on a delay-locked loop, wherein the delay-locked loop extracts the pseudocode phase error by the difference between the early code correlation result and the late code correlation result, and adjusts the pseudocode numerically controlled oscillator based on the pseudocode phase error. Carrier recovery is performed based on Costas phase-locked loop, and frequency-locked loop is combined to assist in carrier frequency offset acquisition, so as to dynamically compensate for Doppler frequency offset and Doppler rate of change in satellite downlink radio frequency signal; The pseudocode tracking results and carrier recovery results are used as the synchronization basis for the despreading, bit synchronization, frame synchronization and decoding processes.

9. The method as described in claim 6, characterized in that, In the tracking processing flow, based on the zero-IF in-phase quadrature signal, the sum-path signal and the difference-path signal are synchronized, and demodulated to obtain the azimuth error voltage and the pitch error voltage, including: Pseudocode recovery and carrier recovery are performed based on the sum-path signal, and the automatic gain control voltage corresponding to the sum-path signal is obtained; The differential signal is normalized based on the automatic gain control voltage to reduce the impact of the gain difference between the sum and difference channels on the error demodulation. The differential signal after amplitude normalization is subjected to phase shifting, integration and detection processing to obtain the azimuth error voltage and the elevation error voltage. Based on the telemetry and control status information corresponding to the telemetry data, at least one of the following parameters is adjusted: tracking loop bandwidth, tracking accuracy threshold, or error voltage output parameter.

10. The method as described in claim 6, characterized in that, Also includes: After generating the remote control transmission signal, a portion of the remote control transmission signal is split into a small loop detection signal; The small loop detection signal is spread spectrum demodulated to extract the small loop remote control data; The remote control data of the small ring is compared bit by bit with the original remote control command issued by the host computer to obtain the remote control small ring comparison result. The comparison range of the bitwise comparison includes the pre-complementary sequence, the instruction text, and the post-complementary sequence, and the correctness of the transmission of the remote control instruction is determined based on the comparison result of the remote control ring.

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