Multi-source forwarding system based on RFSoC

Abstract

The invention provides a multi-source forwarding system based on an RFSoC, and belongs to the technical field of radio frequency signal processing. According to the invention, hardware implementation of C and X wave band radio frequency front-end links is designed, a temperature sensor is used in cooperation to compensate for the condition that the link gain stability of a hardware circuit is reduced due to the change of environment temperature, and a polynomial fitting algorithm is used to assist the hardware link to dynamically regulate and control the power of a transmitting signal of the radio frequency front-end link in real time. The high power stability requirement of the radio frequency front end is realized; in addition, nonlinear distortion of the power amplifier is suppressed by adopting a digital pre-distortion technology; the beam of the transmitting antenna points to the target direction through the intelligent beam forming technology, and efficient transmission of energy is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of radio frequency signal processing, and in particular relates to a C-band and X-band calibrator multi-source forwarding system based on RFSoC. Background Art

[0002] In active calibrator systems, the transmitter's RF link has extremely stringent requirements for power level and stability to ensure high-quality signal transmission. Particularly in C- and X-band active calibrators, due to the high-frequency and high-power characteristics of the transmitted signal, power stability of the transmitted signal determines calibration accuracy, placing even higher demands on the performance of the transmit link. However, changes in ambient temperature can significantly affect the gain stability of the RF link, thereby affecting the accuracy of the transmitted signal and, in turn, the overall performance of the transmitter. The nonlinear characteristics of the power amplifier can produce nonlinear distortion when high-power transmission is required, thus affecting performance. The transmitting antenna's beam pointing and target orientation can also affect RF signal transmission accuracy. Therefore, a system that can dynamically adjust the RF front-end gain stability in real time is urgently needed to address the impact of ambient temperature changes and nonlinear distortion on transmission performance. Furthermore, how to associate the transmitting antenna with the target orientation to achieve maximum transmission efficiency is also a challenge that needs to be addressed.

[0003] The Zynq UltraScale+ RFSoC integrates an ARM processor, a high-speed FPGA, and high-precision RF components on a single-chip SoC platform to achieve high-performance RF data converters and RF analog technologies. The subsystem includes eight RF-ADCs that support digital down-conversion (DUC) and eight RF-DACs that support digital up-conversion. This enables direct RF acquisition, supports flexible analog design, improves accuracy, and reduces power consumption. Summary of the Invention

[0004] To address the existing problem of ambient temperature changes affecting the gain stability of the RF link, thereby affecting the accuracy of the transmitted signal, the present invention provides a multi-source forwarding system based on RFSoC. By designing the hardware implementation of the C- and X-band RF front-end links, a temperature sensor is used to compensate for the reduction in link gain stability caused by ambient temperature changes in the hardware circuit. A polynomial fitting algorithm is used to assist the hardware link in dynamically regulating the power of the RF front-end link transmitted signal in real time, thereby achieving the high requirements for RF front-end power stability. In addition, digital pre-distortion technology is used to suppress the nonlinear distortion of the power amplifier. Intelligent beamforming technology is used to point the transmitting antenna beam to the target direction, achieving efficient energy transmission.

[0005] The technical solution adopted in the present invention is as follows:

[0006] A multi-source forwarding system based on RFSoC, including a radio frequency transmission front-end link and an RFSoC digital front-end;

[0007] The radio frequency transmission front end includes a C-band horizontal polarization radio frequency front end transmission channel, a C-band vertical polarization radio frequency front end transmission channel, an X-band horizontal polarization radio frequency front end transmission channel, an X-band vertical polarization radio frequency front end transmission channel, a first temperature sensor, and a second temperature sensor;

[0008] The C-band horizontally polarized RF front-end transmission channel and the C-band vertically polarized RF front-end transmission channel each include a first coupler, a first bandpass filter, a driver amplifier, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler connected in sequence;

[0009] The first coupler is configured to directly input the C-band signal output by the DAC module of the RFSoC into the first bandpass filter;

[0010] The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier;

[0011] The driver amplifier is used to preliminarily amplify the C-band analog signal to enable the signal to reach a power range that can be amplified by the subsequent power amplifier, and transmit the amplified signal to the digitally controlled attenuator;

[0012] The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the C-band signal after gain adjustment to the temperature compensation equalizer;

[0013] The temperature compensation equalizer is used to perform temperature compensation on the C-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier;

[0014] The power amplifier is used to amplify the C-band signal within a preset power range so that the power of the C-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter;

[0015] The second bandpass filter is used to filter the amplified C-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler;

[0016] The second coupler is used to transmit the filtered C-band signal to the C-band transmission channel so as to be radiated into space through the antenna.

[0017] The X-band vertically polarized RF front-end transmission channel and the X-band horizontally polarized RF front-end transmission channel both include a first coupler, a first bandpass filter, a driver amplifier, a mixer, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler, which are connected in sequence. They also include a shared frequency synthesizer and a first power divider.

[0018] The frequency synthesizer is configured to receive a frequency synthesis control signal sent by the RFSoC digital front end, generate a local oscillator signal according to the frequency synthesis control signal, and send the local oscillator signal to the first power divider;

[0019] The first power divider distributes the received local oscillator signal equal power and inputs it into the mixers of the vertical and horizontal polarization RF front-end transmission channels;

[0020] The first coupler is used to directly input the C-band signal output by the RFSoC into the first bandpass filter;

[0021] The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier;

[0022] The driver amplifier is used to preliminarily amplify the C-band analog signal to bring the signal to a power range that can be amplified by a subsequent power amplifier, and transmit the amplified signal to the mixer; the mixer is used to receive the C-band analog signal and a local oscillator signal, and up-convert the C-band analog signal to the X-band based on the local oscillator signal and input it to the digitally controlled attenuator;

[0023] The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the X-band signal after gain adjustment to the temperature compensation equalizer;

[0024] The temperature compensation equalizer is used to perform temperature compensation on the X-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier;

[0025] The power amplifier is used to amplify the X-band signal within a preset power range so that the power of the X-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter;

[0026] The second bandpass filter is used to filter the amplified X-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler;

[0027] The second coupler is used to transmit the filtered X-band signal to the X-band transmission channel so as to be radiated into space through the antenna.

[0028] The first temperature sensor and the second temperature sensor are used to detect the ambient temperature of the C-band and X-band RF transmission front-end channels respectively, obtain the first temperature value and the second temperature value, and send the first temperature value and the second temperature value to the PS module in the RFSoC digital front-end;

[0029] The RFSoC digital front end includes an RF-DAC module and a PS module;

[0030] Among them, the RF-DAC module is used to perform digital-to-analog conversion to generate a C-band analog signal; the PS module is used to receive a first temperature value and a second temperature value, generate a corresponding gain control signal based on the first temperature value and the second temperature value, and send it to the digitally controlled attenuator; it is also used to generate a frequency synthesis control signal of the local oscillator signal and send it to the frequency synthesizer of the RF front end.

[0031] Preferably, the RFSoC digital front end also includes a PL module and an RF-ADC module, which are used to implement a beamforming function to optimize beam pointing; and are also used to implement a digital pre-distortion function to suppress the nonlinear distortion of the power amplifier and optimize the power accuracy of the transmitted signal.

[0032] Preferably, the beamforming function is implemented as follows:

[0033] The RF-ADC module collects echo signals from the antenna array, converts the collected analog echo signals into digital signals, and transmits them to the PL module and the PS module; the PL module performs real-time calculations based on the received digital signals to obtain channel state information, and transmits it to the PS module;

[0034] The PS module is configured with a machine learning model, the input data of the machine learning model is channel state information, the output data is a beam weight matrix, and the beam weight matrix is sent to the PL module;

[0035] The PL module performs complex weighting on the signals of each antenna channel based on the beam weight matrix, and uses the weighted signals as the C-band signals input to the RF transmit front-end link. It should be noted that the four C-band signals generated by the RFSoC digital front-end are only C-band in frequency, but the other parameters of the C-band signals entering different channels (C-band horizontally polarized RF front-end transmit channel, C-band vertically polarized RF front-end transmit channel, X-band horizontally polarized RF front-end transmit channel, and X-band vertically polarized RF front-end transmit channel) are not the same.

[0036] Preferably, the digital predistortion function is implemented as follows:

[0037] The RF-ADC module obtains the gain distortion curve of the power amplifier and transmits it to the PL module;

[0038] The PL module calculates the gain-distortion curve based on the digital pre-distortion algorithm to obtain an anti-distortion curve, then calculates and updates the anti-distortion curve based on the envelope of the next output signal of the power amplifier and the anti-distortion curve; finally, based on the updated anti-distortion curve, the nonlinear distortion of the C-band signal input to the RF transmission front-end link is compensated.

[0039] Preferably, at different temperatures, the power value of the RF-DAC output signal after passing through the RF front-end transmission path is measured to obtain a gain-temperature variation curve; based on different ambient temperatures and corresponding gain variation values, a fitting algorithm is used to obtain a gain temperature compensation curve; in the PS module, corresponding gain control signals are obtained based on the compensation curve for different temperature values and coarse adjustment is performed; at the same time, compensation adjustment is performed in other device processors that receive the transmission signal of the RF transmission link.

[0040] Preferably, the RF front end further includes: a first power detector and a second power detector set in the C band; a first power detector and a second power detector set in the X band;

[0041] The first power detector and the second power detector are used to respectively detect the power of the output signals in the horizontally polarized and vertically polarized RF front-end channels, and send the power detection values to the PS module; the PS module combines the temperature value and the power detection value to generate a gain control signal.

[0042] Preferably, the first temperature sensor, the second temperature sensor, the second coupler, the first power detector, the second power detector, the frequency synthesizer, the digitally controlled attenuator in the RF front end and the PS module in the RFSoC digital front end transmit data via the SPI protocol.

[0043] Beneficial effects of the present invention:

[0044] The present invention provides a C- and X-band calibrator multi-source forwarding system based on RFSoC (reconfigurable system on chip) for transmitting radio frequency power signals. The system realizes efficient and high-quality transmission of analog signals in the two bands by designing precise C- and X-band radio frequency front-end links. At the same time, in order to solve the problem of reduced accuracy of calibration signals caused by changes in ambient temperature and nonlinear distortion of amplifiers during the operation of the radio frequency link, a temperature sensor is used on the basis of a temperature-compensated equalizer to establish a radio frequency link temperature-gain change curve, thereby compensating for gain changes caused by temperature changes. In addition, digital pre-distortion technology is used to suppress the nonlinear distortion of the power amplifier when the required output power is too high, thereby affecting the accuracy of the calibration signal. Intelligent beamforming technology based on a deep learning model is also used to achieve precise pointing of the antenna main lobe to the target direction, thereby achieving efficient energy transmission.

[0045] Overall, this invention provides a multi-source forwarding system based on an RFSoC. This system integrates the RF signal transmission chain on a single board, achieving efficient signal generation and providing high-precision power signals for active calibrators. It also mitigates the accuracy degradation caused by temperature variations and nonlinear distortion, resulting in a highly stable and accurate system suitable for demanding RF measurement and calibration scenarios. It also addresses transmission issues such as reduced signal transmission accuracy caused by antenna pointing errors, providing a high-precision RF signal forwarding technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is the RFSoC digital front-end architecture in the embodiment.

[0047] Figure 2 4 is a block diagram of the multi-source forwarding technology based on RFSoC in an embodiment.

[0048] Figure 3 FIG. 4 is a block diagram of a beamforming solution in an embodiment. FIG.

[0049] Figure 4 2 is a block diagram of a digital predistortion solution in an embodiment. DETAILED DESCRIPTION

[0050] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0051] The multi-source forwarding system based on RFSOC of this embodiment includes a radio frequency front end, an RFSOC digital front end, a beamforming solution and a digital predistortion technology.

[0052] The radio frequency transmission front end includes a C-band horizontal polarization radio frequency front end transmission channel, a C-band vertical polarization radio frequency front end transmission channel, an X-band horizontal polarization radio frequency front end transmission channel, an X-band vertical polarization radio frequency front end transmission channel, a first temperature sensor, and a second temperature sensor.

[0053] The C-band horizontally polarized RF front-end transmitting channel and the C-band vertically polarized RF front-end transmitting channel both include a first coupler, a first bandpass filter, a driving amplifier, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler connected in sequence.

[0054] The first coupler is used to directly input the C-band signal output by the DAC module of the RFSoC into the first bandpass filter.

[0055] The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier.

[0056] The driving amplifier is used to preliminarily amplify the C-band analog signal so that the signal reaches a power range that can be amplified by the subsequent power amplifier, and transmit the amplified signal to the digitally controlled attenuator.

[0057] The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the C-band signal after gain adjustment to the temperature-compensated equalizer.

[0058] The temperature compensation equalizer is used to perform temperature compensation on the C-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier.

[0059] The power amplifier is used to amplify the C-band signal within a preset power range so that the power of the C-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter.

[0060] The second bandpass filter is used to filter the amplified C-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler.

[0061] The second coupler is used to transmit the filtered C-band signal to the C-band transmission channel so as to be radiated into space through the antenna.

[0062] The X-band vertically polarized RF front-end transmission channel and the X-band horizontally polarized RF front-end transmission channel both include a first coupler, a first bandpass filter, a driver amplifier, a mixer, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler, which are connected in sequence. They also include a shared frequency synthesizer and a first power divider.

[0063] The frequency synthesizer is configured to receive a frequency synthesis control signal sent by the RFSoC digital front end, generate a local oscillator signal according to the frequency synthesis control signal, and send the local oscillator signal to the first power divider;

[0064] The first power divider distributes the received local oscillator signal with equal power and inputs it into the mixers of the vertical and horizontal polarization RF front-end transmission channels.

[0065] The first coupler is used to directly input the C-band signal output by the RFSoC into the first bandpass filter.

[0066] The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier.

[0067] The driver amplifier is used to preliminarily amplify the C-band analog signal so that the signal reaches a power range that can be amplified by the subsequent power amplifier, and transmit the amplified signal to the mixer; the mixer is used to receive the C-band analog signal and the local oscillator signal, and up-convert the C-band analog signal to the X-band based on the local oscillator signal and input it to the digitally controlled attenuator.

[0068] The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the X-band signal after gain adjustment to the temperature compensation equalizer.

[0069] The temperature compensation equalizer is used to perform temperature compensation on the X-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier.

[0070] The power amplifier is used to amplify the X-band signal within a preset power range so that the power of the X-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter;

[0071] The second bandpass filter is used to filter the amplified X-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler;

[0072] The second coupler is used to transmit the filtered X-band signal to the X-band transmission channel so as to be radiated into space through the antenna.

[0073] The first temperature sensor and the second temperature sensor are used to respectively detect the ambient temperature of the C-band and X-band RF transmission front-end channels, obtain the first temperature value and the second temperature value, and send the first temperature value and the second temperature value to the PS module in the RFSoC digital front-end.

[0074] The RFSoC digital front end includes an RF-DAC module and a PS module.

[0075] Among them, the RF-DAC module is used to perform digital-to-analog conversion to generate a C-band analog signal; the PS module is used to receive a first temperature value and a second temperature value, generate a corresponding gain control signal based on the first temperature value and the second temperature value, and send it to the digitally controlled attenuator; it is also used to generate a frequency synthesis control signal of the local oscillator signal and send it to the frequency synthesizer of the RF front end.

[0076] The RFSoC digital front end also includes a PL module and an RF-ADC module, which are used to implement beamforming function to optimize beam pointing; and are also used to implement digital pre-distortion function to suppress the nonlinear distortion of the power amplifier and optimize the power accuracy of the transmitted signal.

[0077] The beamforming function is implemented as follows:

[0078] The RF-ADC module collects the echo signal of the antenna array, converts the collected analog echo signal into a digital signal, and transmits it to the PL module and the PS module; the PL module performs real-time calculation based on the received digital signal to obtain channel state information, and transmits it to the PS module.

[0079] The PS module is configured with a machine learning model, the input data of the machine learning model is channel state information, the output data is a beam weight matrix, and the beam weight matrix is sent to the PL module.

[0080] The PL module performs complex weighting on the signals of each antenna channel based on the beam weight matrix, and uses the weighted signals as the C-band signals input to the RF transmit front-end link. It should be noted that the four C-band signals generated by the RFSoC digital front-end are only C-band in frequency, but the other parameters of the C-band signals entering different channels (C-band horizontally polarized RF front-end transmit channel, C-band vertically polarized RF front-end transmit channel, X-band horizontally polarized RF front-end transmit channel, and X-band vertically polarized RF front-end transmit channel) are not the same.

[0081] The digital pre-distortion function is implemented as follows:

[0082] The RF-ADC module obtains the gain distortion curve of the power amplifier and transmits it to the PL module.

[0083] The PL module calculates the gain-distortion curve based on a digital pre-distortion algorithm to obtain an anti-distortion curve, then calculates and updates the anti-distortion curve based on the envelope of the power amplifier's next output signal and the anti-distortion curve. A feedback loop is formed to continuously update the anti-distortion curve to match the distortion characteristics of the RF power amplifier. Finally, the nonlinear distortion of the C-band signal input to the RF transmission front-end link is compensated based on the updated anti-distortion curve.

[0084] The present invention provides a multi-source forwarding technology for a C- and X-band active calibrator based on RFSoC. By detecting the temperature of the RF transmission system and combining the fitting algorithm to dynamically adjust the gain stability of the RF front-end link in real time, the accuracy of the transmitter's transmission signal is guaranteed; at the same time, the digital pre-distortion technology is used to suppress the nonlinear distortion of the power amplifier, further ensuring the accurate forwarding of the calibration signal; finally, the power signal is transmitted to the transmitting antenna and radiated into space. The transmitting antenna uses phased array antenna technology and utilizes an intelligent beamforming solution to train a deep learning model to achieve precise pointing of the antenna main lobe to the target direction. The system can effectively cope with the impact of ambient temperature changes, amplifier nonlinear distortion, and antenna beam azimuth pointing problems on transmission performance, ensure high-quality signal transmission, and provide important technical support for the optimization of the active calibrator system.

Claims

1. A multi-source forwarding system based on RFSoC, characterized in that: Including RF transmission front-end link and RFSoC digital front-end; The radio frequency transmission front end includes a C-band horizontal polarization radio frequency front end transmission channel, a C-band vertical polarization radio frequency front end transmission channel, an X-band horizontal polarization radio frequency front end transmission channel, an X-band vertical polarization radio frequency front end transmission channel, a first temperature sensor, and a second temperature sensor; The C-band horizontally polarized RF front-end transmission channel and the C-band vertically polarized RF front-end transmission channel each include a first coupler, a first bandpass filter, a driver amplifier, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler connected in sequence; The first coupler is configured to directly input the C-band signal output by the DAC module of the RFSoC into the first bandpass filter; The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier; The driver amplifier is used to preliminarily amplify the C-band analog signal to enable the signal to reach a power range that can be amplified by the subsequent power amplifier, and transmit the amplified signal to the digitally controlled attenuator; The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the C-band signal after gain adjustment to the temperature compensation equalizer; The temperature compensation equalizer is used to perform temperature compensation on the C-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier; The power amplifier is used to amplify the C-band signal within a preset power range so that the power of the C-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter; The second bandpass filter is used to filter the amplified C-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler; The second coupler is used to transmit the filtered C-band signal to the C-band transmission channel so as to be radiated into space through the antenna. The X-band vertically polarized RF front-end transmission channel and the X-band horizontally polarized RF front-end transmission channel both include a first coupler, a first bandpass filter, a driver amplifier, a mixer, a digitally controlled attenuator, a temperature-compensated equalizer, a power amplifier, a second bandpass filter, and a second coupler, which are connected in sequence. They also include a shared frequency synthesizer and a first power divider. The frequency synthesizer is configured to receive a frequency synthesis control signal sent by the RFSoC digital front end, generate a local oscillator signal according to the frequency synthesis control signal, and send the local oscillator signal to the first power divider; The first power divider distributes the received local oscillator signal equal power and inputs it into the mixers of the vertical and horizontal polarization RF front-end transmission channels; The first coupler is used to directly input the C-band signal output by the RFSoC into the first bandpass filter; The first bandpass filter is used to suppress out-of-band interference, avoid aliasing and signal intermodulation, prevent the interference signal from being amplified, and transmit the filtered C-band analog signal to the driver amplifier; The driver amplifier is used to preliminarily amplify the C-band analog signal to bring the signal to a power range that can be amplified by a subsequent power amplifier, and transmit the amplified signal to the mixer; the mixer is used to receive the C-band analog signal and a local oscillator signal, and up-convert the C-band analog signal to the X-band based on the local oscillator signal and input it to the digitally controlled attenuator; The digitally controlled attenuator is used to receive the gain control signal sent by the RFSoC, dynamically adjust the gain of the RF front-end transmission channel according to the gain control signal, and transmit the X-band signal after gain adjustment to the temperature compensation equalizer; The temperature compensation equalizer is used to perform temperature compensation on the X-band analog signal after gain control, and transmit the temperature compensated signal to the power amplifier; The power amplifier is used to amplify the X-band signal within a preset power range so that the power of the X-band signal meets the power requirement of the transmitting antenna and transmit the signal to the second bandpass filter; The second bandpass filter is used to filter the amplified X-band signal, filter out irrelevant signals such as interference signals and intermodulation components, ensure the quality of the transmitted signal, and transmit the signal to the second coupler; The second coupler is used to transmit the filtered X-band signal to the X-band transmission channel so as to be radiated into space through the antenna. The first temperature sensor and the second temperature sensor are used to detect the ambient temperature of the C-band and X-band RF transmission front-end channels respectively, obtain the first temperature value and the second temperature value, and send the first temperature value and the second temperature value to the PS module in the RFSoC digital front-end; The RFSoC digital front end includes an RF-DAC module and a PS module; Among them, the RF-DAC module is used to perform digital-to-analog conversion to generate a C-band analog signal; the PS module is used to receive a first temperature value and a second temperature value, generate a corresponding gain control signal based on the first temperature value and the second temperature value, and send it to the digitally controlled attenuator; it is also used to generate a frequency synthesis control signal of the local oscillator signal and send it to the frequency synthesizer of the RF front end.

2. A multi-source forwarding system based on RFSoC as claimed in claim 1, characterized in that: The RFSoC digital front end also includes a PL module and an RF-ADC module, which are used to implement beamforming function to optimize beam pointing; and are also used to implement digital pre-distortion function to suppress the nonlinear distortion of the power amplifier and optimize the power accuracy of the transmitted signal.

3. A multi-source forwarding system based on RFSoC as claimed in claim 2, characterized in that: The beamforming function is implemented as follows: The RF-ADC module collects echo signals from the antenna array, converts the collected analog echo signals into digital signals, and transmits them to the PL module and the PS module; the PL module performs real-time calculations based on the received digital signals to obtain channel state information, and transmits it to the PS module; The PS module is configured with a machine learning model, the input data of the machine learning model is channel state information, the output data is a beam weight matrix, and the beam weight matrix is sent to the PL module; The PL module performs complex weighting on the signals of each antenna channel based on the beam weight matrix, and uses the weighted signals as the C-band signals input to the RF transmit front-end link. It should be noted that the four C-band signals generated by the RFSoC digital front-end are only C-band in frequency, but the other parameters of the C-band signals entering different channels (C-band horizontally polarized RF front-end transmit channel, C-band vertically polarized RF front-end transmit channel, X-band horizontally polarized RF front-end transmit channel, and X-band vertically polarized RF front-end transmit channel) are not the same.

4. A multi-source forwarding system based on RFSoC according to claim 2 or 3, characterized in that: The digital predistortion function is implemented as follows: The RF-ADC module obtains the gain distortion curve of the power amplifier and transmits it to the PL module; The PL module calculates the gain-distortion curve based on the digital pre-distortion algorithm to obtain an anti-distortion curve, then calculates and updates the anti-distortion curve based on the envelope of the next output signal of the power amplifier and the anti-distortion curve; finally, based on the updated anti-distortion curve, the nonlinear distortion of the C-band signal input to the RF transmission front-end link is compensated.

5. A multi-source forwarding system based on RFSoC as claimed in claim 4, characterized in that: At different temperatures, the power value of the RF-DAC output signal after passing through the RF front-end transmission path is measured to obtain a gain-temperature variation curve. Based on different ambient temperatures and the corresponding gain variation values, a fitting algorithm is used to obtain a gain temperature compensation curve. In the PS module, the corresponding gain control signal is obtained based on the compensation curve for different temperature values and coarse adjustment is performed. At the same time, compensation adjustment is performed in the processors of other devices that receive the transmission signal of the RF transmission link.

6. The multi-source forwarding system based on RFSoC according to claim 5, characterized in that: The radio frequency front end further includes: a first power detector and a second power detector set in the C band; a first power detector and a second power detector set in the X band; The first power detector and the second power detector are used to respectively detect the power of the output signals in the horizontally polarized and vertically polarized RF front-end channels, and send the power detection values to the PS module; the PS module combines the temperature value and the power detection value to generate a gain control signal.

7. The multi-source forwarding system based on RFSoC according to claim 6, characterized in that: The first temperature sensor, the second temperature sensor, the second coupler, the first power detector, the second power detector, the frequency synthesizer, the digitally controlled attenuator in the RF front end and the PS module in the RFSoC digital front end transmit data through the SPI protocol.

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