BeiDou timing security isolation and protection device and method

Abstract

This application discloses a BeiDou time synchronization security isolation and protection device and method. The BeiDou time synchronization security isolation and protection method includes: performing radio frequency processing on received satellite signals to obtain a radio frequency processed signal; monitoring and identifying the received satellite signals to obtain observation data; performing reliability calculations based on the radio frequency processed signal and the observation data to obtain a first calculation result; performing time calculations based on the radio frequency processed signal and the observation data to obtain a second calculation result; and generating a satellite regenerated signal based on the first calculation result and the second calculation result. The embodiments of this application can eliminate interference in satellite signals, improving the security and accuracy of the time synchronization equipment.

Description

Technical Field

[0001] This application belongs to the field of satellite technology, and more specifically, relates to a BeiDou timing security isolation and protection device and method. Background Technology

[0002] Satellite time synchronization is a crucial and widely used technology. It refers to the process by which basic computing devices, core networks in communication systems, and other equipment synchronize their local clocks using high-precision time signals released by navigation satellites (such as GPS and BeiDou). During satellite time synchronization, various types of interference may occur, potentially impacting the security of basic computing devices, core networks in communication systems, and other equipment. Summary of the Invention

[0003] The purpose of this application is to provide a BeiDou time synchronization security isolation and protection device and method, which can improve the security of downstream computing devices during satellite time synchronization.

[0004] In a first aspect, embodiments of this application provide a BeiDou timing security isolation and protection method, comprising: performing radio frequency processing on received satellite signals to obtain a radio frequency processed signal; monitoring and identifying the received satellite signals to obtain observation data; performing reliability calculation based on the radio frequency processed signal and the observation data to obtain a first calculation result; performing time calculation based on the radio frequency processed signal and the observation data to obtain a second calculation result; and generating a satellite regeneration signal based on the first calculation result and the second calculation result.

[0005] In one embodiment, the step of monitoring and identifying the received satellite signal to obtain observation data includes: capturing the received satellite signal to obtain a first captured signal; tracking the first captured signal to obtain a tracked signal; and performing baseband digital signal processing and navigation calculation on the tracked signal to obtain the observation data.

[0006] In one embodiment, the step of performing baseband digital signal processing and navigation calculation on the tracked signal to obtain the observation data includes: measuring the tracked signal to obtain at least one of the carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase of the tracked signal; and determining the observation data based on at least one of the carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase of the tracked signal.

[0007] In one embodiment, the step of performing reliability calculations based on the radio frequency processed signal and the observation data to obtain a first calculation result includes: performing position, velocity, and time calculations on the radio frequency signal and the observation data to obtain position, velocity, and time calculation results; and performing reliability calculations on the position, velocity, and time calculation results to obtain the first calculation result.

[0008] In one embodiment, the step of performing time calculation based on the radio frequency processed signal and the observation data to obtain a second calculation result includes: generating a second acquisition signal based on the radio frequency processed signal and the observation data; performing differential calculation on the second acquisition signal to obtain differential calculation data; and performing time alignment calculation on the differential calculation data to obtain the second calculation result.

[0009] In one embodiment, performing time alignment calculation on the differential calculation data to obtain the second calculation result includes: obtaining a time correction number for the differential calculation data; determining the inter-satellite error; and obtaining the second calculation result based on the time correction number and the inter-satellite error.

[0010] In one embodiment, generating a satellite regenerated signal based on the first calculation result and the second calculation result includes: generating a merged calculation result based on the first calculation result and the second calculation result; performing digital-to-analog conversion processing on the merged calculation result to generate the satellite regenerated signal.

[0011] In one embodiment, generating a merged calculation result based on the first calculation result and the second calculation result includes: regenerating and time-calibrating the radio frequency processed signal and the non-interference signal in the observation data based on the first calculation result and the second calculation result to obtain the merged calculation result.

[0012] Secondly, this application also provides a BeiDou timing security isolation and protection device, which can implement the method provided in any embodiment of this application.

[0013] In one implementation, the BeiDou timing security isolation and protection device includes: a radio frequency processing module, a monitoring and identification module, an information processing module, a high-precision processing module, and a regeneration module. The radio frequency processing module processes received satellite signals to obtain a processed radio frequency signal. The monitoring and identification module monitors and identifies the received satellite signals to obtain observation data. The information processing module performs reliability calculations based on the processed radio frequency signal and the observation data to obtain a first calculation result. The high-precision processing module performs time calculations based on the processed radio frequency signal and the observation data to obtain a second calculation result. The regeneration module generates a satellite regeneration signal based on the first and second calculation results.

[0014] Thirdly, embodiments of this application also provide an electronic device, the electronic device comprising: a processor and a memory; the memory being used to store a program for the electronic device to execute the method provided in any embodiment of this application, and to store data involved in implementing the method provided in any embodiment of this application; the processor being configured to execute the program stored in the memory.

[0015] Fourthly, embodiments of this application also provide a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause a computer to execute the charging method of the electronic atomizer provided in any embodiment of this application.

[0016] The apparatus and method provided in this application can receive satellite signals and generate clean regenerated signals based on the valid content in the satellite signals. When the core network, basic computing equipment, and other devices of the communication system obtain the regenerated signals and perform time synchronization based on the regenerated signals, the core network and basic computing equipment will not be affected by interference signals in the satellite signals, ensuring that the time calibration and security of the timing equipment such as the core network and basic computing equipment are not affected by interference in the satellite signals. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A scenario diagram provided for an embodiment of this application;

[0019] Figure 2 A schematic diagram of a BeiDou time synchronization security isolation and protection method provided in this application embodiment;

[0020] Figure 3 This is a schematic diagram of the structure of the BeiDou timing security isolation and protection device provided in the embodiments of this application;

[0021] Figure 4 A schematic diagram of the BeiDou time synchronization security isolation and protection system provided in the embodiments of this application;

[0022] Figure 5 This is a schematic diagram of another BeiDou timing security isolation and protection device provided in an embodiment of this application;

[0023] Figure 6 A structural diagram of the modules included in the BeiDou timing security isolation and protection device provided in another embodiment of this application;

[0024] Figure 7 A structural diagram of the unit components included in the BeiDou timing security isolation and protection device provided in another embodiment of this application;

[0025] Figure 8 A structural diagram of the sub-units included in the BeiDou timing security isolation and protection device provided in another embodiment of this application;

[0026] Figure 9 A possible data transmission diagram of the BeiDou time synchronization security isolation and protection device provided in another embodiment of this application;

[0027] Figure 10 This is a schematic diagram of the main components of a docile clock module in another embodiment of this application. Detailed Implementation

[0028] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0029] Figure 1 This demonstrates the relationship between satellites and timing equipment. In the communication system, timing equipment such as the core network 11 and basic computing devices 12 calibrate their system time using signals transmitted from satellite 13 and provide timing services based on that system time. Figure 1 In the scenario shown, the time synchronization device relies on the frequency stability of the local clock source (such as a crystal oscillator or atomic clock). A time synchronization system measures and records the drift characteristics of the local clock when an external reference is available; when the external reference is lost, it autonomously calculates the time based on these characteristics.

[0030] This application provides a BeiDou timing security isolation and protection method, such as... Figure 2 As shown, it includes the following steps S21 to S25.

[0031] Step S21: Perform radio frequency processing on the received satellite signal to obtain the radio frequency processed signal.

[0032] In this embodiment, step S21 converts the extremely weak high-frequency analog signal in the sky into a low-frequency digital signal of suitable strength for digital circuit processing. The received satellite signal may include at least one of BeiDou satellite signals and GPS satellite signals.

[0033] In this embodiment, after the antenna receives the satellite signal, it performs bandpass filtering, low-noise amplification, down-conversion, intermediate frequency filtering and amplification, analog-to-digital conversion, and other operations on the satellite signal to obtain a radio frequency processed signal. In addition, step S21 further includes converting the received BeiDou satellite signal into a GPS satellite signal, or vice versa.

[0034] In a possible implementation, step S21 includes down-conversion and analog-to-digital conversion. The down-conversion operation involves shifting the spectrum of the received high-frequency radio frequency signal to a lower intermediate frequency (IF) or baseband frequency through a mixing process to obtain a down-converted signal. The analog-to-digital conversion operation involves performing an analog-to-digital conversion on the down-converted signal to obtain a radio frequency processing signal. The down-conversion operation allows satellite signals of different frequencies to be shifted to a fixed IF, facilitating standardization in subsequent processing modules. Furthermore, before down-conversion, bandpass filtering and low-noise amplification can be performed on the received satellite signal. The bandpass filtering operation involves filtering the received high-frequency radio frequency signal to allow satellite signals within a set frequency band to pass. The low-noise amplification operation involves amplifying the received high-frequency radio frequency signal using a low-noise amplifier.

[0035] Step S22: Monitor and identify the received satellite signals to obtain observation data.

[0036] In this embodiment, the received BeiDou satellite signals and / or GPS satellite signals are further monitored and identified to extract all necessary information for positioning, velocity measurement, and time synchronization. Step S22 mainly includes: capturing BeiDou satellite signals and / or GPS satellite signals, and tracking BeiDou satellite signals and / or GPS satellite signals. During the implementation of step S22, a reference clock signal is also acquired, and a clock synchronization signal is obtained based on the reference clock signal.

[0037] In a possible implementation, step S22 further includes: monitoring and identifying the received satellite signals to capture available satellite signals. Then, the available satellite signals are precisely measured to obtain raw observations for positioning, navigation, or data demodulation. Steps S22 and S21 can be performed simultaneously or sequentially in any order.

[0038] Step S23: Perform reliability calculation based on the radio frequency processed signal and the observation data to obtain the first calculation result.

[0039] In this embodiment, before performing final high-precision positioning using observation data, step S23 assesses and verifies the quality of all input data and the reliability of the initial solution results, determines the reliability calculation of the radio frequency processing signal and observation data, and obtains the reliability calculation results. Step S23 can further perform PVT calculation (Position, Velocity, Time) on the reliability calculation results, and the output data can be used as the first calculation result. The first calculation result may include: the receiver's position (latitude, longitude, or ECEF coordinates), velocity (northeast or east-west coordinate system or velocity in the ECEF coordinate system), accurate UTC time, positioning accuracy factor (PDOP, etc.), and solution status.

[0040] Step S24: Perform time calculation based on the radio frequency processed signal and the observation data to obtain a second calculation result.

[0041] In step S24, based on the first calculation result, the radio frequency processed signal, and the observation data, a high-precision time calculation can be performed to derive a high-precision Coordinated Universal Time (UTC) or GPS Time (GPST) from the satellite signal and synchronize it with the receiver's local clock to obtain a second calculation result. Further, the second calculation result may include the transmission / reception time relationship.

[0042] Step S25: Generate a satellite regenerated signal based on the first calculation result and the second calculation result.

[0043] In this embodiment, the first and second calculation results can be merged into clock signals. A high-precision, high-reliability clock signal is extracted from both results and used as the clock signal for the regenerated signal. Based on other useful information from the first and second results, a radio frequency (RF) signal highly consistent with the real satellite signal in format, time, and content is reconstructed (or "regenerated") to obtain the satellite regenerated signal. Further, during the reverse reconstruction to obtain the RF signal highly consistent with the real satellite signal in format, time, and content, the known navigation message corresponding to the first calculation result, the satellite orbit and clock difference corresponding to the second calculation result, a high-precision time reference, and a known signal system are used to synthesize a signal in the baseband digital domain. This signal is then converted from digital to analog and up-converted to restore the original RF frequency, resulting in a regenerated signal with the same RF frequency as the original satellite signal. Known signal systems include C / A (Coarse / Acquisition) code, Gold code, etc.

[0044] exist Figure 2 In the illustrated embodiment, after step S25, the satellite regenerated signal is also transmitted to the timing device.

[0045] In one embodiment, the step of monitoring and identifying the received satellite signal to obtain observation data includes: capturing the received satellite signal to obtain a first captured signal; tracking the first captured signal to obtain a tracked signal; and performing baseband digital signal processing and navigation calculation on the tracked signal to obtain the observation data.

[0046] Furthermore, the received satellite signals are monitored and identified to obtain usable satellite signals. This includes: capturing the received satellite signals to obtain the target signal; performing phase-locked loop (PLL) tracking or frequency-locked loop (FLL) tracking on the target signal to obtain carrier phase observations and pseudorange; then, obtaining the satellite message based on the carrier phase observations and pseudorange; and extracting observation data from the satellite message. Further, after obtaining the observation data, the extracted raw observation data, observation data containing navigation message data, and the receiver's own status information are encapsulated according to a standard format. The satellite message may include navigation messages, data messages, etc.

[0047] In one embodiment, the step of performing baseband digital signal processing and navigation calculation on the tracked signal to obtain the observation data includes: measuring the tracked signal to obtain at least one of the carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase of the tracked signal; and determining the observation data based on at least one of the carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase of the tracked signal.

[0048] In possible implementations, system time is also obtained based on pseudorange, number of satellites, etc. The tracked signal is the signal obtained after signal tracking is completed. After locking onto the tracked signal, observations within the tracked signal are obtained. These observations are objective data of the tracked signal and may include at least one of carrier-to-noise ratio, pseudomoment, number of satellites, and carrier phase. Observations may also include Doppler shift, which reflects the relative radial velocity between the satellite and the receiver. Based on at least one of carrier-to-noise ratio, pseudomoment, number of satellites, and carrier phase, and combined with the navigation message in the satellite signal, the data is encapsulated to obtain the observation data.

[0049] In one embodiment, the step of performing reliability calculations based on the radio frequency processed signal and the observation data to obtain a first calculation result includes: performing position, velocity, and time calculations on the radio frequency signal and the observation data to obtain position, velocity, and time calculation results; and performing reliability calculations on the position, velocity, and time calculation results to obtain the first calculation result.

[0050] In possible implementations, the position, velocity, and time calculation results can be referred to as PVT calculation results. Before calculating the PVT results, the security of the RF processed signal and / or observation data can also be verified. During the process of obtaining the PVT calculation results, the security calculation results can still be used to generate a weighted dataset, and then PVT calculations can be performed on the RF processed signal and observation data based on the weighted dataset to obtain the PVT calculation results.

[0051] In a possible implementation, the ratio of carrier power to noise power spectral density can be obtained first from the radio frequency (RF) processed signal and / or observation data. Then, based on the ratio of carrier power to noise power spectral density, signals with signal strength less than a set threshold in the RF processed signal and / or observation data are removed. Next, preliminary positioning data is obtained from the RF processed signal and / or observation data. Based on the preliminary positioning data, data with large positioning discrepancies in the RF processed signal and / or observation data are removed to obtain the remaining data. The remaining data is then smoothed based on the carrier phase and pseudorange to obtain smoothed remaining data. Finally, a weighted dataset is obtained based on the satellite elevation angle corresponding to the remaining data and the observation data, as well as the ratio of carrier power to noise power spectral density.

[0052] In a possible implementation, obtaining the weighted dataset based on the satellite elevation angle corresponding to the smoothed remaining data and the observation data, and the ratio of carrier power to noise power spectral density, includes: calculating the elements of the weighted dataset based on the sum of the remaining radio frequency processed signal r21 and the remaining observation data, the product of the remaining radio frequency processed signal r21 and the remaining observation data, the square root of the ratio of carrier power to noise power spectral density, and the sine of the satellite elevation angle corresponding to the observation data.

[0053] In a possible implementation, it is assumed that signals with signal strength less than a set threshold are removed from the RF processed signal and / or observation data. The resulting RF processed signal and / or observation data is represented as r1 (including RF processed signal r11 and observation data r12). Further, data with large positioning discrepancies in the RF processed signal and / or observation data r1 are removed and smoothed to obtain the smoothed remaining data, represented as r2 (including the remaining RF processed signal r21 and the remaining observation data r22). The ratio of carrier power to noise power spectral density is d. The elevation angle of the satellite corresponding to the observation data is represented as a. The weighted dataset consists of multiple rows of elements, and each row element mij of the weighted dataset is calculated according to the following formula.

[0054] mij=[[ln(r21+r22) 2×i +di / (r21×r22)]× ] / sinai×e ai+bj. Where mij represents the element in the i-th row and j-th column, di represents d at the i-th time, and dj represents the combined value of d for the j-th satellite at all times in this acquisition. e is a natural constant, and b is an empirical value of the weighting constant.

[0055] In one embodiment, the step of performing time calculation based on the radio frequency processed signal and the observation data to obtain a second calculation result includes: generating a second acquisition signal based on the radio frequency processed signal and the observation data; performing differential calculation on the second acquisition signal to obtain differential calculation data; and performing time alignment calculation on the differential calculation data to obtain the second calculation result.

[0056] In a possible implementation, satellite signal reconstruction can be performed based on radio frequency processed signals and observation data to obtain a second acquired signal, which is then time-aligned. In a possible implementation, the second acquired signal may include: reconstructed carrier phase observations, differential corrections, precise orbit, and clock bias files. When performing differential calculations on the second acquired signal to obtain differential calculation data, differential calculations are performed on the reconstructed carrier phase observations based on the differential corrections to obtain differential calculation data. Then, time alignment calculations are performed on the differential calculation data based on system time, local time, precise orbit, and clock bias files to obtain a second calculation result. Further, performing time alignment calculations on the differential calculation data based on system time, local time, precise orbit, and clock bias files to obtain a second calculation result includes: obtaining standard time coordinates based on system time, local time, precise orbit, and clock bias files; and aligning the differential calculation data with the standard time coordinates using interpolation to obtain the second calculation result.

[0057] In one embodiment, performing time alignment calculation on the differential calculation data to obtain the second calculation result includes: obtaining a time correction number for the differential calculation data; determining the inter-satellite error; and obtaining the second calculation result based on the time correction number and the inter-satellite error.

[0058] In a possible implementation, obtaining the second calculation result based on the time correction and inter-satellite error may include obtaining a standard time coordinate based on the time correction and inter-satellite error; and then aligning the differential calculation data based on the standard time coordinate to obtain the second calculation result.

[0059] In possible implementations, the differential calculation data is represented as df, the time correction can be represented as rt, the inter-satellite error can be represented as es, and the time correction is calculated as follows.

[0060] rt=[ ] 2 / ti 2Where dfi is the df at time i, and ti is the reference time at time i.

[0061] The second calculation result is c=log rt es.

[0062] In one embodiment, generating a satellite regenerated signal based on the first calculation result and the second calculation result includes: generating a merged calculation result based on the first calculation result and the second calculation result; performing digital-to-analog conversion processing on the merged calculation result to generate the satellite regenerated signal.

[0063] In this embodiment of the application, generating a combined calculation result based on the first calculation result and the second calculation result includes: determining the pseudorange in the regenerated signal based on the first calculation result and the second calculation result; generating a modulated navigation message based on the first calculation result; injecting the navigation message into a modulated waveform based on the carrier phase in the second calculation result and the pseudorange to generate a regenerated radio frequency signal; and generating a combined calculation result based on the regenerated radio frequency signal.

[0064] In one embodiment, generating a merged calculation result based on the first calculation result and the second calculation result includes: regenerating and time-calibrating the radio frequency processed signal and the non-interference signal in the observation data based on the first calculation result and the second calculation result to obtain the merged calculation result.

[0065] In a possible implementation, the merging calculation result is obtained by regenerating and time-calibrating the radio frequency processed signal and the non-interference signal in the observation data based on the first calculation result and the second calculation result. This includes: regenerating the radio frequency processed signal and the non-interference signal in the observation data based on the first calculation result and the second calculation result to obtain a regenerated radio frequency signal; time-calibrating the regenerated radio frequency signal based on the standard time coordinate used in the second calculation result to obtain a time-calibrated regenerated radio frequency signal; then, using the differential data aligned in the second calculation result, verifying and correcting the regenerated radio frequency signal to generate verification and correction data; determining the theoretical error based on the verification and correction data; and then obtaining the merging calculation result if the theoretical error is less than a preset error threshold.

[0066] In one implementation, during the merging phase, all received satellite signals that have passed reliability screening and are identified as unreliable, affected by multipath, or originating from faulty satellites will be completely excluded from the merging list and will not participate in the signal generation. When using received satellite signals that have passed reliability screening, these signals can be merged with the modulated regenerated radio frequency signal to obtain a complete merged calculation result.

[0067] This application also provides a BeiDou timing security isolation and protection device, the structure of which is as follows: Figure 3 As shown, the system includes: a radio frequency processing module 31, a monitoring and identification module 32, an information processing module 33, a high-precision processing module 34, and a regeneration module 35. Specifically, the radio frequency processing module 31 processes received satellite signals to obtain a processed radio frequency signal; the monitoring and identification module 32 monitors and identifies the received satellite signals to obtain observation data; the information processing module 33 performs reliability calculations based on the processed radio frequency signal and the observation data to obtain a first calculation result; the high-precision processing module 34 performs time calculations based on the processed radio frequency signal and the observation data to obtain a second calculation result; and the regeneration module 35 generates a regenerated satellite signal based on the first and second calculation results.

[0068] exist Figure 3 In the illustrated embodiment, the radio frequency processing module and the monitoring and identification module are used to receive satellite signals. The radio frequency processing module and the monitoring and identification module can receive satellite signals synchronously. In the monitoring and identification module, the received satellite signals can be converted into their corresponding types. For example, if a GPS satellite signal is received, it can be converted to a BeiDou satellite signal; if a BeiDou satellite signal is received, it can be converted to a GPS satellite signal.

[0069] Figure 4 This application illustrates the architecture of the BeiDou timing security isolation and protection device combined with a communication system in an embodiment of this application. The BeiDou timing security isolation and protection device is configured between the satellite and the timing equipment, which may include basic computing equipment, a core network, etc. Satellite signals transmitted from the satellite to ground equipment are received by the BeiDou timing security isolation and protection device provided in this embodiment. The device then regenerates the received satellite signals to obtain a regenerated signal, which is then transmitted in real time. The timing equipment monitors and receives the regenerated signal and performs time calibration and timing based on it. Therefore, this application also provides a signal processing system, including... Figure 4 The satellite and timing equipment shown also include the BeiDou timing security isolation and protection device provided in any embodiment of this application.

[0070] In one possible implementation of this application, in Figure 3 Based on the embodiments shown, refer to Figure 5 As shown, the radio frequency processing module includes a down-conversion unit and an analog-to-digital converter. Figure 5 The illustrated radio frequency (RF) antenna receives signals transmitted from the satellite in real time. After receiving the satellite signals, the RF antenna sends the satellite signals to the down-conversion unit. The down-conversion unit converts the high-frequency RF signal into a low-frequency intermediate frequency (IF) signal. The analog-to-digital converter (ADC) receives the IF signal from the down-conversion unit and converts it into a digital signal. The RF processing module's ADC sends the digital signal obtained from the satellite signal conversion to the information processing module. In one possible implementation, the structure of the down-conversion unit is as follows: Figure 7 As shown, the system includes a suppression filter, a local oscillator, a mixer, an intermediate frequency (IF) filter, and an IF amplifier. In a possible implementation, the suppression filter can be a mirror suppression filter. The signal input from the RF antenna is received by the suppression filter, which outputs a purified, interference-free satellite signal (in RF format) based on the original satellite signal input from the RF antenna. The mixer outputs a mixed signal based on the power and frequency control words of the BeiDou timing security isolation protection device. The mixed signal and the purified, interference-free satellite signal are input together into the mixer, outputting a bandwidth-mixed signal with multiple frequency components. The IF filter is used to output an IF signal based on the bandwidth-mixed signal. The IF amplifier is used to amplify the IF signal to obtain the amplified IF satellite signal.

[0071] The monitoring and identification module receives the raw satellite signals transmitted by the antenna, then performs baseband processing and decoding on the raw satellite signals. The module includes an acquisition unit, a local time unit, and a system time unit. The acquisition unit can acquire multiple signals and send them to multiple tracking channels, such as signal tracking channel 1, signal tracking channel 2, ..., signal tracking channel N, where N is an integer greater than 2. The acquisition unit performs a coarse search within the received signals to identify portions belonging to satellite signals, determining the channel, frequency, code phase, etc., of these portions. Then, multiple tracking channels perform a fine-grained search along the channel dimensions of the satellite signals coarsely searched by the acquisition unit. Each tracking channel tracks one satellite. If a tracking channel corresponds to a satellite signal in the digital signal, that tracking channel outputs the satellite signal for that satellite.

[0072] The information processing module receives digital signals from the analog-to-digital converter. It includes a data preprocessing unit, a PVT calculation unit, a point positioning unit, and an integrity detection unit. The data preprocessing unit preprocesses the digital signals, including filtering, smoothing, and correction. The PVT calculation unit integrates the preprocessed data from the data preprocessing unit for positioning, velocity measurement, and timing, outputting a complete navigation solution. The point positioning unit constructs a pseudorange observation equation based on the preprocessed data, linearizes it, and then uses the least squares method or Kalman filtering to solve for four state variables, including three-dimensional position and receiver clock error, binding these state variables to the navigation solution. The integrity detection unit detects the integrity of the navigation solution and state variables; if integrity is detected, it outputs the navigation solution and the corresponding state variables.

[0073] The high-precision processing module includes a differential information acquisition unit, a high-precision data processing unit, and an interface protocol unit. This module performs differential information acquisition, high-precision data processing, and interface protocol operations. The regeneration module includes a digital-to-analog converter. Furthermore, the BeiDou timing security isolation protection device also includes a disciplined clock module. The differential information acquisition unit can obtain differential information from a reference station outside the BeiDou timing security isolation protection device, or it can obtain differential information from a wireless device in the communication system. The differential information acquisition unit can input the obtained differential information and its source into the high-precision data processing unit. The high-precision data processing unit determines the correction data for the captured satellite signal based on the differential information. In possible implementations, refer to... Figure 8As shown, the high-precision data processing unit includes: a correction subunit, a comparison subunit, a parameter extraction subunit, a data generation subunit, and a modulation subunit. The correction subunit generates correction data based on the differential information acquired by the differential information acquisition unit; then, based on the correction data, it corrects the satellite signal tracked by the signal channel. The comparison subunit compares the digital signal output from the analog-to-digital converter with the satellite signal output from the signal tracking channel, identifies the portion of the digital signal that belongs to the satellite signal, and separates this portion from other digital signals. The parameter extraction subunit extracts parameters from the portion of the digital signal that belongs to the satellite signal. These extracted parameters may include signal quality indicators such as carrier wave, carrier phase, pseudorange (code phase), Doppler shift, and carrier-to-noise ratio, as well as the navigation data bitstream. The data generation subunit receives the parameters extracted by the parameter extraction subunit and the interface protocol information output by the interface protocol unit to generate a navigation message. When generating navigation messages, the data generation subunit first generates the navigation message data content based on the parameters extracted by the parameter extraction subunit. Then, according to the interface protocol information, it modifies the navigation message data content to ensure it conforms to the format specified by the corresponding interface protocol. The modulation subunit uses the data generated by the data generation subunit to generate a modulated signal. Then, the high-precision processing module outputs the modulated signal to the regeneration module.

[0074] The local time unit is used to obtain the local time, which can refer to the local time of the BeiDou time synchronization security isolation protection device. The local time can be generated by the clock signal inside the BeiDou time synchronization security isolation protection device. The system time unit is used to obtain the system time by calculating the pseudorange and the receiver's position. Further, the system time unit obtains the clock difference by comparing the pseudorange corresponding to the received satellite signal with the positional distance between the receiver's position and the actual position of the satellite. Then, the system time unit performs a weighted average of the clock differences of all satellites corresponding to the received satellite signal to obtain a high-precision system time.

[0075] Furthermore, the disciplined clock module interacts with the deception detection and interference identification module, providing system information to other modules and maintaining high accuracy and stability of the system time through a sophisticated clock synchronization algorithm. The main components of the disciplined clock module can be found in [reference needed]. Figure 10As shown, the system includes an input reference signal processing unit, a core processing and control unit, a local clock discipline unit, an output status monitoring unit, and a maintenance unit. The input reference signal processing unit receives and decodes BeiDou satellite signals or other high-level time reference signals, extracting high-precision standard second pulses and standard time. It verifies the integrity of the input time reference signal, eliminating spoofing and interference signals to ensure the reliability of the input time reference. A standard second pulse can refer to 1 PPS (1 pulse per second). The core processing and control unit continuously compares the phase difference between the 1 PPS generated by the local clock and the 1 PPS extracted from the BeiDou signal. It then performs loop filtering calculations on the phase difference to obtain the loop filtering result, which is applied to the local oscillator of the local clock discipline unit. The local clock discipline unit receives the loop filtering calculation result, applies it to the local oscillator, and obtains the frequency signal and / or phase signal output by the local oscillator. The output status monitoring unit is used to monitor the status of the disciplined loop in real time, such as the lockout status, phase error value, and local clock health, and to issue an alarm when abnormalities occur. The maintenance unit is used to output a disciplined, highly stable frequency signal and a high-precision time pulse / time code that is highly synchronized with BeiDou time, based on the frequency signal and / or phase signal output by the local oscillator.

[0076] Furthermore, the power management module is primarily used to provide power to the device. It can include two power supplies, employing a dual-power supply design. Additionally, the power management module can also support a multi-power supply design.

[0077] The regeneration module performs digital-to-analog conversion (DA conversion) and controls the output of safety signals. By regenerating digital signals, it ensures signal stability and accuracy. The module receives modulated signals, performs digital-to-analog conversion to obtain radio frequency (RF) signals, and then transmits them to downstream devices.

[0078] In one possible example, the data transmission relationship between BeiDou timing security isolation and protection devices refers to... Figure 9As shown, the antenna receives the raw satellite signal and outputs it to the down-conversion unit and the acquisition unit. The down-conversion unit outputs the down-converted low-frequency intermediate frequency (IF) signal to the analog-to-digital converter (ADC). The ADC performs analog-to-digital conversion on the IF signal to obtain a digital signal, which is then sent to the acquisition unit. The acquisition unit integrates the raw satellite signal and the digital signal and outputs the acquisition signal. The acquisition signal is output to each signal tracking channel for tracking. Simultaneously, the signal tracking channel also tracks the acquisition signal output by the acquisition unit based on the local time signal output by the local time unit, achieving more precise signal positioning than the acquisition unit itself. The specific satellite signal tracked by each signal tracking channel is output to the data preprocessing unit for preprocessing to obtain the preprocessed satellite signal. The preprocessed satellite signal is then output to the PVT calculation unit, which calls the single-point positioning unit for processing to obtain the calculated satellite signal. Both the calculated satellite signal and the preprocessed satellite signal are input to the integrity detection unit for integrity detection. Simultaneously, the digital signal output from the analog-to-digital converter (ADC) is also sent to the integrity detection unit. Based on the integrity detection results of each signal, the integrity detection unit determines the final detected signal output to the regeneration module. The specific satellite signals tracked by each signal tracking channel, as well as the digital signals output from the ADC, are sent to the differential information acquisition unit. The differential information acquired by the differential information acquisition unit, the specific satellite signals tracked by each signal tracking channel, and the digital signals output from the ADC are then sent to the high-precision data processing unit for high-precision processing. Meanwhile, the remaining raw measurement data from the terminals are sent to the high-precision data processing unit via the interface protocol unit. The high-precision data processing unit combines the received data from multiple sources and ultimately outputs a high-precision signal. This high-precision signal is then sent to the integrity detection unit for integrity detection. The integrity detection unit can obtain the detection results based on the high-precision signal, digital signal, or the specific satellite signals output from each signal tracking channel, determining the integrity of the high-precision signal. If the integrity of the high-precision signal is low, it can supplement the high-precision signal with specific satellite signals or digital signals to obtain the detected signal. Furthermore, the power supply can provide power to any unit or module.

[0079] This application also provides a BeiDou timing security isolation and protection device, the structure of which is as follows: Figure 6 As shown, it includes a service module, a monitoring module, a signal generation module, a data sharing and interaction module, a hardware driver module, and a hardware control module. Among them, Figure 3 , Figure 4 and Figure 5 The BeiDou timing security isolation and protection device shown can be installed in Figure 3 , Figure 5The diagram shows an information processing module, a high-precision processing module, and a security signal regeneration module. The service module, which can be located within the power management module, is used for signal transmission with the operating system, starting or calling the power management module, and implementing various operating system functions. The hardware driver module is located within the information processing module and / or the high-precision processing module, used to drive antennas, signal generators, and other related hardware. The hardware control module can be located within... Figure 3 or Figure 5 The information processing module and / or high-precision processing module shown are used for related hardware such as antennas and signal generators. The hardware control module can transmit signals with the hardware driver module, and can control the startup and operation of the hardware driver module. The service module can also be used to start services related to the monitoring module, data sharing and interaction module, and signal generation module. The monitoring module can also monitor the signals generated by the signal generation module. The signal generator can be used to generate regenerated radio frequency signals. The data sharing and interaction module can be set in... Figure 3 or Figure 5 The information processing module and / or high-precision processing module shown are used to obtain system time, first calculation result, and second calculation result for the information processing module and / or high-precision processing module, and also to transmit the merged calculation result to the regeneration module. The signal generation module can obtain hardware signals through the data sharing and interaction module. The monitoring module can be set in... Figure 3 or Figure 5 The monitoring and identification module shown is used to start and invoke the monitoring and identification module. The signal generation module can be set in... Figure 3 or Figure 5 The regeneration module shown is used to start and invoke the regeneration module.

[0080] The methods and apparatus provided in this application can block deception and interference in satellite signals and isolate electromagnetic attacks. The output security signal is a clean, hardened satellite signal, and all interfering signals are eliminated. The methods and apparatus provided in this application can also monitor and analyze received satellite signals in real time and issue timely alarms when anomalies are detected. Based on algorithm software, signal quality is evaluated and analyzed to determine the integrity of the satellite constellation; alarms are issued when events such as signal interruption, satellite malfunction, or signal interference are detected. With the methods and apparatus provided in this application, service can continue uninterrupted even when satellite timing is denied. Normal security signal output can still be maintained even when the actual number of satellite signals fluctuates, the quality degrades, or even completely stops.

[0081] This application also provides an electronic device, which includes a processor and a memory; the memory is used to store a program for the electronic device to execute the method provided in any embodiment of this application, and to store data involved in implementing the method provided in any embodiment of this application; the processor is configured to execute the program stored in the memory.

[0082] The embodiments of the present invention described above are combinations of elements and features of the invention. Unless otherwise stated, elements or features may be considered optional. Individual elements or features may be practiced without combination with other elements or features. Furthermore, embodiments of the invention may be constructed by combining some elements and / or features. The order of operations described in the embodiments of the invention may be rearranged. Some constructions of any embodiment may be included in another embodiment and may be replaced by corresponding constructions of another embodiment. It will be apparent to those skilled in the art that claims that are not explicitly referenced in the appended claims may be combined to form embodiments of the invention, or may be included as new claims in modifications made after the submission of this invention.

[0083] In firmware or software configuration, the embodiments of the present invention can be implemented in the form of modules, processes, functions, etc. Software code can be stored in a memory unit and executed by a processor. The memory unit is located inside or outside the processor and can send data to and receive data from the processor via various known means.

[0084] The various aspects of the systems and methods described herein can be implemented as functions programmable into any type of circuit, including programmable logic devices (PLDs) such as field-programmable gate arrays (FPGAs), programmable array logic (PAL) devices, electronically programmable logic and memory devices, standard cell-based devices, and application-specific integrated circuits (ASICs). Other possibilities for implementing these aspects of the system include: microcontrollers with memory, such as electronically erasable programmable read-only memory (EEPROM), embedded microprocessors, firmware, software, etc. Furthermore, these aspects of the system can be embodied in microprocessors with software-based circuit emulation, discrete logic (sequential and combinational), custom devices, fuzzy (neural) logic devices, and any combination of the various device types described above. Of course, underlying device technologies can be provided in various component types, such as metal-oxide-semiconductor field-effect transistor (MOSFET) technologies such as complementary metal-oxide-semiconductor (CMOS), bipolar technologies such as emitter-coupled logic (ECL), polymer technologies (e.g., silicon conjugated polymers and metal conjugated polymer metal structures), hybrid analog and digital, etc.

[0085] The various functions or processes disclosed herein can be described, based on their behavior, register transfers, logic components, transistors, geometric layouts, and / or other characteristics, as data and / or instructions embodied in various computer-readable media. Computer-readable media that may contain such formatted data and / or instructions include, but are not limited to, various forms of non-volatile storage media (e.g., optical, magnetic, or semiconductor storage media) and carrier waves, which can be used to transmit such formatted data and / or instructions via wireless, optical, or wired signal media, or any combination thereof. Such data and / or instructions can be processed by a processing entity (e.g., one or more processors) upon receipt by any of various circuits (e.g., a computer).

[0086] The above description of the illustrated embodiments of the systems and methods is not intended to be exhaustive or to limit the systems and methods to the precise forms disclosed. While specific embodiments and examples of system components and methods have been described herein for illustrative purposes, those skilled in the art will understand that various equivalent modifications can be made within the scope of the systems, components, and methods. The teachings of the systems and methods provided herein can be applied to other processing systems and methods, and are not limited to those described above.

[0087] Those skilled in the art will understand that various changes and / or modifications can be made to the invention illustrated in particular embodiments without departing from the spirit or scope of the broad description of the invention. Therefore, these embodiments are to be considered illustrative rather than restrictive in all respects. Furthermore, the invention includes any combination of features described with respect to different embodiments (including those in the abstract section), even if such feature or combination of features is not expressly specified in the claims or the detailed description of these embodiments.

[0088] Generally, the terminology used in the following claims should not be construed as limiting the systems and methods to the specific embodiments disclosed in the specification and claims, but should be interpreted as encompassing all processing systems operating under the claims. Therefore, the systems and methods are not limited by this disclosure, but their scope is determined entirely by the claims.

[0089] Unless the context explicitly requires otherwise, throughout the specification and claims, the words “comprising,” “including,” and “including” should be interpreted in a encompassing sense, not in an exclusive or exhaustive sense; that is, in the sense of “including but not limited to.” The use of singular or plural words also includes both singular and plural, respectively. Furthermore, “this article,” “in the following,” “above,” “below,” and words with similar meanings refer to the application as a whole, and not to any particular part of the application. When the word “or” is used to refer to a list of two or more items, the word “or” includes all of the following interpretations: any item in the list, all items in the list, and any combination of items in the list.

[0090] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0091] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for secure isolation and protection of BeiDou timing, characterized in that, include: The received satellite signals are processed by radio frequency (RF) to obtain the RF processed signal; The received satellite signals are monitored and identified to obtain observation data; Based on the radio frequency processed signal and the observation data, a reliability calculation is performed to obtain a first calculation result; Based on the radio frequency processed signal and the observation data, time calculation is performed to obtain a second calculation result; Based on the first calculation result and the second calculation result, a satellite regenerated signal is generated; The step of performing reliability calculations based on the radio frequency processed signal and the observation data to obtain a first calculation result includes: Based on the ratio of carrier power to noise power spectral density, signals with signal strength less than a set threshold are removed from the radio frequency processed signals and / or observation data. Preliminary positioning data is obtained based on radio frequency processed signals and / or observation data; Based on the preliminary positioning data, data with large positioning discrepancies in the radio frequency processed signals and / or observation data are removed to obtain the remaining data; The remaining data is smoothed based on the carrier phase and pseudorange to obtain the smoothed remaining data. The weighted dataset is obtained by combining the remaining smoothed data and the satellite elevation angles corresponding to the observed data, as well as the ratio of carrier power to noise power spectral density. Based on the weighted dataset, time, velocity, and position calculations are performed on the radio frequency processed signal and observation data to obtain the position, velocity, and time calculation results. The reliability of the calculated position, velocity, and time results is calculated to obtain the first calculation result.

2. The method according to claim 1, characterized in that, The process of monitoring and identifying the received satellite signals to obtain observation data includes: The received satellite signal is captured to obtain a first capture signal; The first captured signal is tracked to obtain the tracked signal; The tracked signal is subjected to baseband digital signal processing and navigation calculation to obtain the observation data.

3. The method according to claim 2, characterized in that, The step of performing baseband digital signal processing and navigation calculations on the tracked signal to obtain the observation data includes: Measure the tracked signal to obtain at least one of the following: carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase. The observation data is determined based on at least one of the following: carrier-to-noise ratio, pseudo-moment, number of satellites, and carrier phase of the tracked signal.

4. The method according to claim 1, characterized in that, The process of obtaining the weighted dataset based on the satellite elevation angle corresponding to the smoothed residual data and the observed data, and the ratio of carrier power to noise power spectral density, includes: The elements of the weighted dataset are calculated based on the sum of the remaining radio frequency processed signal r21 and the remaining observation data, the product of the remaining radio frequency processed signal r21 and the remaining observation data, the square root of the ratio of carrier power to noise power spectral density, and the sine of the elevation angle of the satellite corresponding to the observation data.

5. The method according to claim 1, characterized in that, The step of performing time calculations based on the radio frequency processed signal and the observation data to obtain a second calculation result includes: A second acquisition signal is generated based on the radio frequency processed signal and the observation data; Differential calculation is performed on the second captured signal to obtain differential calculation data; Time alignment calculation is performed on the differential calculation data to obtain the second calculation result.

6. The method according to claim 5, characterized in that, The step of performing time alignment calculation on the differential calculation data to obtain the second calculation result includes: Obtain the time correction for the differential calculation data; Determine inter-satellite errors; The second calculation result is obtained based on the time correction and inter-satellite error.

7. The method according to claim 1, characterized in that, The step of generating a satellite regenerated signal based on the first calculation result and the second calculation result includes: Based on the first calculation result and the second calculation result, a combined calculation result is generated; The merged calculation results are subjected to digital-to-analog conversion to generate the satellite regenerated signal.

8. The method according to claim 7, characterized in that, The step of generating a combined calculation result based on the first calculation result and the second calculation result includes: Based on the first calculation result and the second calculation result, the non-interference signal in the radio frequency processed signal and the observation data are regenerated and time-calibrated to obtain the merged calculation result.

9. A BeiDou timing synchronization security isolation and protection device, characterized in that, The BeiDou timing security isolation and protection device is used in real-time according to any one of claims 1-8. The BeiDou timing security isolation and protection device includes: a radio frequency processing module, a monitoring and identification module, an information processing module, a high-precision processing module, and a regeneration module. The radio frequency processing module is used to perform radio frequency processing on the received satellite signals to obtain radio frequency processed signals; The monitoring and identification module is used to monitor and identify the received satellite signals to obtain observation data; The information processing module is used to perform reliability calculations based on the radio frequency processed signal and the observation data to obtain a first calculation result; The high-precision processing module is used to perform time calculations based on the radio frequency processed signal and the observation data to obtain a second calculation result; The regeneration module is used to generate a satellite regeneration signal based on the first calculation result and the second calculation result.

10. An electronic device, characterized in that, The electronic device includes: a processor and a memory; The memory is used to store a program for the electronic device to execute the method as described in any one of claims 1-8, and to store data related to implementing the method as described in any one of claims 1-8; The processor is configured to execute programs stored in the memory.

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