93 results about "Tracking loop" patented technology

The invention discloses an airborne low-detectability photoelectric long-distance stable tracking and aiming method based on a time-sensitive opposite target, and belongs to the technical field of airborne photoelectric detection and target tracking. The method comprises the following steps: step 1, target detection and miss distance calculation: in a level flight section of an airplane, imaging a target in a field of view, carrying out target detection by adopting an optical flow method, and detecting a moving target by analyzing a motion vector of pixel points in an image sequence; and resolving the deviation amount of the target image relative to the visual axis in real time, namely the target pixel miss distance. 2, designing a stable tracking loop: designing a two-layer control structure for the stable tracking loop, stably inhibiting high-frequency disturbance by a gyroscope of an inner loop, performing tracking correction on low-frequency deviation by an outer loop based on pixel miss distance, and finally realizing high-precision tracking. On the basis of real-time pixel miss distance feedback, a two-layer control structure is designed, the miss distance fed back by an outer ring tracking loop is converted into an inner ring control instruction, and the tracking precision and stability are improved.

The invention discloses a GNSS (Global Navigation Satellite System) signal spoofing detection method, device and equipment, a storage medium and a program product. The method comprises the following steps: tracking and monitoring a plurality of GNSS satellite signals, calling a tracking loop correlator to carry out autocorrelation operation to obtain the autocorrelation power of each satellite signal, constructing the AP detection quantity of each satellite signal based on the autocorrelation power, verifying the Gaussian property of the AP detection quantity, and carrying out moving average filtering processing on the AP detection quantity conforming to Gaussian distribution to obtain the AP detection quantity of each satellite signal. The method comprises the following steps: acquiring Gaussian distribution characteristic information of a GNSS satellite signal, constructing an AP-MA detection quantity, determining a detection threshold according to the Gaussian distribution characteristic information, detecting the AP-MA detection quantity based on the detection threshold, and judging whether the GNSS satellite signal has deception jamming or not; the AP detection quantity is constructed based on the self-correlation power to carry out signal spoofing detection, so that the detection range and the detection precision are effectively improved, and the timeliness and the stability of spoofing detection are ensured under the condition of not increasing additional equipment and algorithm complexity.

The invention discloses a converter grid following-grid construction control mode smooth switching method suitable for wide-range source-grid state change. The method comprises the following steps: constructing a phase-locked loop control loop, a power outer loop control loop and a current inner loop control loop of a grid following type converter based on constant power control; constructing a voltage control loop, a phase control loop and a voltage and current double-closed-loop control loop of the network construction type converter based on the virtual synchronous generator VSG; calculating real-time output active power P and reactive power Q of the converter; constructing a voltage phase synchronization loop switching control loop and a current instruction tracking loop, and realizing smooth switching of dq-axis current instruction values output by a power outer loop of a following network type and a voltage outer loop of a construction network type; and the output dq-axis current instruction value is transmitted to a current inner loop to generate a final voltage signal, and a PWM wave is output to the converter through a modulation link. According to the method, a voltage phase synchronous switching compensation mechanism is adopted, a voltage amplitude and a phase signal are synchronously corrected in the mode switching process, and smooth change of an inner ring current reference signal is achieved.

The invention discloses a GNSS-R terminal baseband three-ring cooperative tracking method, system and device and a medium, and belongs to the technical field of satellite navigation signal processing, and the method comprises the steps: receiving a digital intermediate frequency BOC modulation satellite navigation signal; establishing a carrier tracking loop, a subcarrier tracking loop and a code tracking loop; performing frequency mixing operation on the digital intermediate frequency BOC modulation satellite navigation signal and a local carrier wave; performing correlation operation on the signal after the frequency mixing operation and a local subcarrier and a local pseudo-random code in sequence; carrying out accumulation processing on a correlation operation result to obtain a correlation accumulation value; respectively calculating error adjustment parameters of the carrier tracking loop, the subcarrier tracking loop and the code tracking loop based on the correlation accumulation values; and when the error adjustment parameters of the carrier tracking ring, the subcarrier tracking ring and the code tracking ring are all within a preset range, outputting navigation data. According to the invention, the problem that a traditional double-ring method cannot fully utilize subcarrier components is solved.

The invention relates to the technical field of satellite navigation meteorological remote sensing, and discloses a water vapor ionized layer snow depth integrated detection method and system. The method comprises the steps that direct and reflected signals of a Beidou satellite are received through fusion antenna array differentiation, carrier phase and pseudo-range observation values are obtained through carrier tracking loop synchronous demodulation, the total atmospheric rainfall amount and the total ionosphere electron content are extracted through a troposphere and ionosphere combined calculation algorithm, the snow depth is inverted through reflection path geometric difference, and the snow depth is calculated. And carrying out space-time synchronization constraint processing on the extended Kalman filter to realize multi-parameter integrated detection. The problems of low efficiency, insufficient precision and lack of cooperative processing caused by independent observation of water vapor, ionized layer and accumulated snow parameters in the prior art are solved, and the observation efficiency and the measurement precision of multi-parameter integrated detection are improved.

The invention relates to a satellite navigation signal weak signal tracking loop switching method. The method comprises the following steps: designing a loop filter of a double-frequency phase-locked loop, a loop filter of a double-frequency frequency-locked loop and a loop filter of a pilot component single-frequency frequency-locked loop based on a Kalman filtering algorithm; constructing observed quantity and state quantity of a Kalman filter based on phase discrimination, frequency discrimination and code discrimination results of the B2a signal and the B1I signal; the state quantity output by the loop filter is fed back to a local carrier generator and a composite spreading code generator for error correction; in the filtering process, the adopted loop filter is switched according to the carrier-to-noise ratio, the phase locking detection index and the frequency locking detection index of the two signals, the corresponding loop filter is adaptively selected to complete parameter estimation, loop locking is further carried out, and signal tracking and positioning are achieved.

Methods, systems, and devices for wireless communications are described. In some examples, a user equipment (UE) may receive configuration information that indicates one or more paging occasions and an idle discontinuous reception (I-DRX) mode. The UE may monitor the one or more paging occasions based at least in part on a transition from a sleep state to a monitoring state in accordance with the I-DRX mode. The UE may receive a paging message associated with the one or more paging occasions based at least in part on the one or more paging occasions being monitored. The paging message is addressed to a different UE, and the paging message may include a demodulation reference signal (DMRS), data, or both. A tracking loop may be adjusted based on the DMRS, the data, or both.

The invention provides a high-mobility platform random access method and system for a low-orbit satellite data chain, and the method comprises the steps: taking a satellite ephemeris and platform navigation information as initial guidance, receiving and analyzing a satellite downlink signal, and carrying out the joint estimation to obtain a space-time frequency parameter; based on the estimated timestamp as a time reference of a frequency hopping pattern, driving a local frequency hopping sequence generator, predicting and verifying the current frequency hopping pattern, and performing frequency offset correction according to the estimated Doppler frequency offset; and in response to successful verification of the frequency hopping pattern, constructing a pre-compensated uplink and starting a frequency hopping pattern tracking loop for fine tuning of the time-space-frequency parameter and the frequency hopping pattern phase, so that the user accesses the low-orbit satellite data link at random and enters steady-state communication. The time-space-frequency alignment problem and the time-varying frequency hopping pattern capturing and tracking problem are synchronously solved, and rapid, reliable and anti-interference random access of the high-mobility platform is achieved.

The invention discloses an automatic bandwidth adjustment system and a rotary transformer digital converter, and relates to the technical field of rotary transformer digital converters, and the system comprises an angle error calculation module, a tracking loop module and an automatic bandwidth adjustment module. The angle error calculation module is used for outputting a first angle error signal and a second angle error signal to the tracking loop module and the automatic bandwidth adjustment module; the tracking loop module is used for receiving the first angle error signal, performing phase tracking on the sine and cosine signals to obtain a second speed signal and a rotating phase signal, and sending the second speed signal to the automatic bandwidth adjusting module; the automatic bandwidth adjusting module is used for comparing the second angle error signal with a preset angle threshold value to obtain a first comparison signal, comparing the second speed signal with a preset speed threshold value to obtain a second comparison signal, and sending the first comparison signal and the second comparison signal to the tracking loop module. Therefore, different system bandwidth coefficients can be switched.

The invention discloses a navigation deception detection method and device based on multiple correlators and variance filtering, equipment and a storage medium, and relates to the technical field of GNSS detection, and the method comprises the steps: receiving a mixed signal containing a real satellite signal, a deception signal and a noise signal; on the basis of the mixed signal, an output amplitude is obtained through a correlator in a tracking loop, an MCTO first-level detection quantity is constructed, and the MCTO first-level detection quantity obeys Gaussian distribution; performing variance filtering processing on the MCTO primary detection quantity to obtain an MCTO-MV secondary detection quantity; determining a detection threshold based on the detection quantity distribution characteristics, and determining a detection probability based on the detection threshold; and obtaining a navigation deception detection result according to the MCTO-MV secondary detection quantity and the detection probability. According to the method, the induced navigation spoofing attack can be timely and effectively detected, and the safety and reliability of a navigation system are improved.

This invention relates to a method and system for monitoring and enhancing the power of GPS P(Y) signals based on civilian signal tracking. The method employs a carrier tracking loop to stably track civilian satellite navigation signals, generating a local carrier with the same frequency and phase as the GPS satellite navigation digital signal. The GPS satellite navigation digital signal is then orthogonally mixed with the local carrier to output the in-phase branch signal u. I (n) and the orthogonal branch signal u Q (n); the in-phase branch signal u I (n), Orthogonal branch signal u Q (n) Perform low-pass filtering and incoherent integration respectively to obtain the average power P of the baseband signal in the in-phase branch. IB Average power P of baseband signal in orthogonal branch QB The average power P of the baseband signal in the same phase branch IB Average power P of baseband signal in orthogonal branch QB The power enhancement state of the current P(Y) signal is determined by comparing it with the weak-state power threshold of the in-phase branch, the strong-state power threshold of the in-phase branch, the strong-state power threshold of the quadrature branch, and the weak-state power threshold of the quadrature branch.

The application relates to the technical field of fraud detection, and discloses a detection method and system for spoofing attacks / natural electromagnetic interference, which comprises: a first detection quantity based on absolute tracking loop output (ATLO); mobile variance filtering processing (ATLO-MV) is performed on the first detection quantity to construct a second detection quantity; and the detection probability information of the second detection quantity of ATLO-MV of multiple satellites is used to distinguish spoofing attacks, natural electromagnetic interference and no interference. Through construction of the first detection quantity based on absolute tracking loop output, subtle fluctuations in tracking loop output can be accurately captured; the second detection quantity of ATLO-MV obtained through mobile variance enhancement processing effectively improves detection sensitivity and anti-noise performance; finally, a new type of detection algorithm is constructed through multi-satellite joint processing (ATLO-MV-MSC) of ATLO-MV, the distinction between no interference, natural electromagnetic interference and spoofing attacks is realized, and the pain point of fuzzy judgment existing in traditional algorithms is solved.

The application discloses a detection synchronization and demodulation design method based on a high-speed burst communication system, comprising the following steps: S1, performing fast acquisition on a burst synchronization sequence in a high-speed QPSK and OQPSK satellite communication system; S2, after the matching flag of the synchronization sequence in S1 is valid, performing M&M frequency offset estimation on current on-the-fly complex signal data and a preset synchronization sequence, generating a corresponding carrier compensation value by using the calculated frequency difference value, and outputting the frequency-compensated on-the-fly complex signal; S3, performing phase estimation on the frequency-compensated on-the-fly signal and the preset synchronization sequence, generating a corresponding phase compensation value by using the calculated phase difference value, and outputting the frequency-phase-compensated on-the-fly signal; and S4, after the frequency-phase compensation is completed, the on-the-fly complex signal is sent into a small-bandwidth synchronization tracking loop to generate a compensation value, a constellation diagram is output, and a symbol hard decision is performed on the loop output to output a synchronization code stream. The application meets the requirements of low bit error rate and missed detection and false detection rate, and provides good demodulation performance.

The present invention discloses a high-sensitivity tracking method for a rotating platform receiver based on a KF, applicable to satellite navigation receiver systems. The method comprises: determining the system state equation and the mean square error matrix equation of the system's a priori estimation error during the Kalman filter prediction process, and determining the relationship between the system's state vector and observation vector; calculating the coherent integral, incoherent and coherent combined integrals of the phase-locked loop in the tracking loop of the satellite navigation receiver in an ideal state, and the incoherent integral signal of the Kalman filter; modifying the mean square error matrix equation of the system's a priori estimation error and the state transfer matrix of the Kalman filter; and performing correction after the Kalman filter predicts the system state. The method squaring the coherent integral and combining it with a phase detector yields an extended incoherent integral, while simultaneously combining it with the Kalman filter to obtain precise positioning information, thereby improving the receiver's tracking sensitivity.

The application discloses a low-orbit satellite network high-precision positioning enhancement method for complex remote terrain construction and belongs to the technical field of satellite navigation. The application comprises the following steps: S1, for the complex working condition of remote terrain construction, satellite observation data, inertial measurement data and environment perception data are collected in real time; S2, inertial measurement unit pre-integration is carried out based on the inertial measurement data, the results of the inertial measurement unit pre-integration are used for dynamic Doppler compensation of a carrier tracking loop of a satellite receiver, satellite original observation values are stabilized and output, quality marks are made according to the metadata of the satellite original observation values, and satellite observation factors with quality weights are generated; S3, a factor graph containing state variables and constraint factors is constructed, the factor graph is subjected to nonlinear optimization, the optimal value of the state variable is solved, and a positioning result is output, the low-orbit satellite network high-precision positioning effectiveness is improved, and the problem of low low-orbit satellite network high-precision positioning effectiveness in the prior art is solved.

The invention discloses a method for rapidly capturing burst spread spectrum signals. The method comprises the following steps: firstly, carrying out ADC sampling on a received intermediate frequency signal, and then carrying out orthogonal down-conversion and low-pass filtering to obtain a same-direction signal and an orthogonal signal; combining the same-direction signal and the orthogonal signal into a complex number form to obtain a complex baseband signal; dividing the complex baseband signal into a plurality of sections, windowing each section of signal, and performing partial matched filtering and fast Fourier transform on the windowed signal to obtain a normalized amplitude-frequency response; thirdly, correcting the original threshold value by using the energy loss, and performing capture judgment by using the corrected threshold value; then, interpolation is carried out by using an A-P-Rife algorithm, and a Doppler frequency fine estimation value is calculated; finally, calculating an interpolation comprehensive confidence coefficient, and if the interpolation comprehensive confidence coefficient is greater than or equal to a set threshold value, adopting a Doppler frequency fine estimation value; otherwise, adopting the Doppler frequency rough estimation value. The probability of large frequency offset caused by direction correction errors can be effectively reduced, and the anti-interference performance and stability of a follow-up tracking loop are improved.

This invention relates to the field of ultrasonic motor drive technology, and discloses a micro-driver for an ultrasonic motor based on the principle of self-excited oscillation and its usage method. The driver includes: an amplification circuit module, comprising a voltage series negative feedback amplification circuit composed of integrated operational amplifiers, the output of which is connected to a feedback network via an inductor; a temperature compensation module, which directly senses temperature changes through the equivalent circuit of the ultrasonic motor and dynamically adjusts circuit parameters; and a frequency selection network module, composed of three impedance elements, which are respectively connected to the temperature compensation module, the amplification circuit module, and the feedback network module. By utilizing the self-excited oscillation principle and the feedback characteristics of the ultrasonic motor, a complex external frequency tracking loop is eliminated, simplifying and miniaturizing the circuit design. The temperature compensation module automatically adjusts the driving frequency, achieving adaptability to resonant frequency drift. Optimized feedback network reduces power consumption and improves driving efficiency.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a New Radio (NR) user equipment (UE) may receive a configuration that configures the NR UE with a capability to use a Long Term Evolution (LTE) cell-specific reference signal (CRS) for updating a tracking loop. The NR UE may receive an LTE CRS. The NR UE may update the tracking loop based at least in part on the LTE CRS. Numerous other aspects are described.

This invention provides a covert time synchronization deception method, device, electronic equipment, and storage medium for satellites, belonging to the field of electronic countermeasures technology. The covert time synchronization deception method includes the following steps: controlling the step size of the target receiver's tracking loop center frequency shift, ensuring that the step size does not exceed the target receiver's loss-of-lock threshold; after the step size of the target receiver's tracking loop center frequency shift stabilizes at a fixed value, altering the timestamp information of the deception signal to complete the deception of the target receiver's timestamp. This invention is based on synchronous deception signal generation technology, which can strip away the correlation peaks of the real navigation satellite signal with a slight power advantage. During the time synchronization deception process, using the deception model established according to this method, it is possible to induce a 1PPS phase shift in the target receiver or even alter its timestamp without changing the target's positioning result, thus achieving covert alteration of the target terminal's signal layer and information layer time synchronization results.

Methods, systems, and devices for wireless communications are described. In some examples, a user equipment (UE) may receive configuration information that indicates one or more paging occasions and an idle discontinuous reception (I-DRX) mode. The UE may monitor the one or more paging occasions based at least in part on a transition from a sleep state to a monitoring state in accordance with the I-DRX mode. The UE may receive a paging message associated with the one or more paging occasions based at least in part on the one or more paging occasions being monitored. The paging message is addressed to a different UE, and the paging message may include a demodulation reference signal (DMRS), data, or both. A tracking loop may be adjusted based on the DMRS, the data, or both.

The application discloses a fusion filtering method of a target tracking signal, and is based on a tracking control system composed of a master control unit, a driving unit and a motion platform; the master control unit comprises a fusion filter and a tracking loop controller; and the motion platform comprises a platform shaft system, a gyroscope and a visual sensing system; the method of the application performs complementary filtering on the miss distance and other sensor signals in an optoelectronic system; compared with the miss distance, the filtered signals can significantly improve the signal frequency and reduce the system delay, and thus the tracking performance of the optoelectronic system is improved.

The invention discloses an agile parameter complex spread spectrum multi-satellite navigation signal sending and receiving method, and belongs to the technical field of navigation. According to the method, the problem that the navigation receiver can wrongly resolve the position of the navigation receiver under the action of the deception signal in a real sequence spread spectrum system is solved. Starting from the anti-deception performance of the waveform, a transmitter maps the original multi-address spread spectrum code of the navigation satellite into a complex spread spectrum sequence through weighted score Fourier transform, so that the navigation waveform is controlled by weighted score Fourier transform parameters, and the transformation parameters are subjected to parameter agility according to a predetermined hopping pattern. For a deception person, the signal constellation diagram generates a Gaussian noise-like characteristic due to the change of the transformation parameters, so that the navigation message data is not easy to be quickly extracted. A receiver of a deception person lacks discrimination information about transformation parameters, the correlation between a generated deception signal and a real signal in a complex field is greatly weakened, and traction to a tracking loop of a target receiver is suppressed. The method can be applied to navigation signal sending and receiving.

Aspects relate to techniques for providing joint discontinuous reception (DRX) warm-up occasions in mixed carrier aggregation (CA) scenarios in which a user equipment (UE) is communicating with different cells using different radio access technologies (RATs), each associated with a different frequency range (e.g., FR1 and FR2). The UE may identify respective warm-up occasions for each of the RATs that occur in a different DRX cycles. The UE may further modify at least one of the warm-up occasions to provide a joint warm-up occasion during the same DRX cycle to perform tracking loop updates for each of the RATs.

The application relates to a multi-path signal detection device and method, which comprises a radio frequency processing module, a carrier tracking loop, a code tracking loop and a multi-path detector connected in sequence. The radio frequency processing module receives satellite signals and sends the signals to the carrier tracking loop after radio frequency processing. The carrier tracking loop sends the received signals to the code tracking loop after stripping the carrier. The code tracking loop outputs the received signals to the multi-path detector after stripping the pseudo code. The multi-path detector is used for detecting whether the received satellite signals are multi-path signals. The application can effectively detect multi-path signals.

The invention discloses a carrier tracking method, system, equipment and medium for a second-order frequency-locked loop assisted third-order phase-locked loop, and the method comprises the steps: receiving an in-phase integral value and a quadrature integral value outputted by a correlator, and carrying out the second-order frequency-locked loop tracking and the third-order phase-locked loop tracking based on the in-phase integral value and the quadrature integral value, the control quantity of the frequency-locked loop and the phase-locked loop is obtained; estimating a carrier-to-noise ratio and a carrier wave attitude of the received signal corresponding to the in-phase integral value and the orthogonal integral value in real time, and determining a first gain coefficient and a second gain coefficient according to the carrier-to-noise ratio and the carrier wave attitude; and generating a final control quantity of the carrier numerical control oscillator based on the control quantities of the frequency-locked loop and the phase-locked loop, the first gain coefficient and the second gain coefficient. By introducing a real-time sensing and dynamic gain control mechanism based on the carrier-to-noise ratio and the carrier wave fluctuation attitude, weighted fusion of contribution of the frequency-locked loop and the phase-locked loop is realized, and the robustness, the precision and the adaptive capacity of the carrier tracking loop under all working conditions can be improved.

In order to solve the problem that a ground operation control system requires that tracking parameters of a monitoring receiver have high consistency, the invention provides a BOC signal fuzzy-matching-free tracking method and device, a receiver and a medium, and the method comprises the following steps: setting the length of a sliding time window; acquiring a pseudo code phase sequence and a carrier phase sequence of the received signal in the current sliding time window; calculating a carrier wave pseudo code consistency value of the current sliding time window based on the pseudo code phase sequence and the carrier wave phase sequence of the current sliding time window; when the carrier wave pseudo code consistency value exceeds the preset threshold, the local pseudo code phase is adjusted according to the carrier wave pseudo code consistency value, error locking of a pseudo code tracking loop is avoided, and unambiguous tracking of BOC signals can be realized under a matching tracking framework.

The invention discloses a resonant grounding system grounding fault disappearance moment judgment method, system, equipment and medium, and relates to the technical field of power distribution network fault detection, and the method comprises the steps: collecting a line mode voltage and a zero mode voltage in a resonant grounding system in real time, and carrying out the anti-aliasing filtering processing of the collected line mode voltage and zero mode voltage, and estimating system power frequency in real time through an adaptive frequency tracking loop based on the filtered line mode voltage, performing synchronous decomposition on the filtered zero mode voltage by using the real-time system power frequency, generating a zero mode error signal, performing sliding energy calculation on the zero mode error signal, defining an energy index, and judging a fault arc extinguishing moment through threshold comparison. According to the invention, through signal acquisition and filtering, adaptive frequency tracking and correction, zero-mode error signal synchronous decomposition, sliding window energy calculation and threshold comparison, the earth fault disappearance moment of the resonance grounding system is captured, and the detection precision, the environmental adaptability and the fault recovery efficiency are significantly improved.

The application relates to a satellite-ground ranging method suitable for a multi-satellite measurement and control situation, and relates to a satellite-ground ranging method. The application aims to solve the problem that a physical layer of advanced on-orbit system system service data stream and pseudo code data stream cannot be compatible in a multi-satellite measurement and control scene. The process is as follows: at a transmitting end: a downlink telemetry uplink remote control signal is directly sequence spread through a CA code at the transmitting end I path, so as to realize transmission of measurement and control information between a satellite and the ground; a pseudo code ranging sequence is directly sequence spread through the CA code at the transmitting end Q path, so as to realize a ranging function between the satellite and the ground; at a receiving end: 1, transmitting signals of different satellites are separated, and a pseudo code phase and a Doppler frequency shift are obtained; 2, a carrier tracking loop and a pseudo code tracking loop are realized to stably work; 3, I path coherent integration output is carried out to output continuous bits; Q path coherent integration output is carried out to output continuous bits, transmission time is solved, and then actual satellite-ground distance is obtained. The application is used in the field of space technology.

An interference signal detection method and an electronic device are applied to a baseband signal processing process of a navigation receiver, and the method comprises the following steps: determining a target branch according to a tracking state of a tracking loop to a satellite; acquiring a power value output by the target branch in the current detection period; obtaining the index number of the correlator with the maximum output power value of the target branch in the current detection period and the index number of the correlator with the maximum output power value of the target branch in the previous detection period; if the power value of at least one branch in the target branches exceeds a preset tracking power threshold and the absolute value of the difference between the index numbers in the current detection period and the previous detection period is not greater than 2, determining that a stable abnormal event occurs, and adding 1 to the numerical value of an update counter; otherwise, subtracting 1 from the numerical value of the updated counter; and after the numerical value of the counter exceeds a preset counter threshold, determining that the satellite has a deception interference signal in a tracking loop, and detecting an interference signal with a code phase close to that of a real signal.

The invention relates to a master-slave node time difference validity judgment method and device. The method comprises the following steps: acquiring time parameters in a time synchronization process of a master node and a slave node; calculating a current actual time difference value between the master node and the slave node based on the time parameter; calculating a current predicted time difference value of the master node and the slave node based on the time parameter; obtaining a current time difference deviation value based on the current actual time difference value and the current predicted time difference value; if the current time difference deviation value is smaller than a preset threshold, the current actual time difference value is judged to be effective, time difference kick caused by calculation errors, external noise and interference can be accurately recognized and filtered, and the problems that time frequency tracking loops of master and slave nodes fluctuate due to convex jump of an existing time difference calculation value, the larger the scene dynamics is, the larger the time difference calculation value is, the larger the time difference calculation value is, and the higher the time difference calculation value is, can be solved. And the time synchronization performance between the master node and the slave node is seriously influenced due to the larger fluctuation of the time frequency tracking loop.