Navigation positioning anti-interference method and system, terminal equipment and storage medium

Abstract

The invention relates to the technical field of navigation and positioning, and discloses a navigation and positioning anti-interference method and system, terminal equipment and a storage medium, and the navigation and positioning anti-interference method comprises the following steps: when signal interference exists, collecting vehicle state data; when the engine is in the non-starting state, the signal strength of the satellite positioning signal is adjusted to the target signal strength; when the engine is in the starting state and the vehicle speed is smaller than or equal to the preset speed, the signal strength of the satellite positioning signal is adjusted to the target signal strength, satellite positioning deviation is compensated based on the vehicle state data, and the target vehicle speed and the target vehicle position are obtained; and when the engine is in the starting state and the vehicle speed is greater than the preset speed, narrowband satellite positioning interference signals are suppressed. According to the invention, differential processing can be carried out when the vehicle-mounted navigation satellite system has signal interference, excessive processing is avoided when the vehicle flames out, energy consumption is saved, the anti-interference capability is enhanced during high-speed driving, and the positioning precision is guaranteed.

Description

Technical Field

[0001] This application relates to the field of navigation and positioning technology, and in particular to a navigation and positioning anti-interference method, system, terminal device and storage medium. Background Technology

[0002] In the fields of intelligent transportation, autonomous driving, and vehicle navigation, GNSS (Global Navigation Satellite System) is a core technological support for achieving precise vehicle positioning, path planning, and driving control. It is widely used in scenarios such as autonomous driving assistance for passenger vehicles, fleet management for commercial vehicles, and precision operations for special vehicles. Currently, vehicle-mounted GNSS systems primarily rely on receiving satellite signals for positioning, while combining this with data fusion from onboard sensors to further improve positioning accuracy and reliability. As the level of autonomous driving increases, the requirements for the stability and accuracy of satellite positioning signals (GNSS signals) significantly increase. Interference with GNSS signals will directly affect vehicle positioning accuracy, potentially leading to navigation deviations, degraded autonomous driving functions, and even safety risks. Summary of the Invention

[0003] In view of this, embodiments of this application provide a navigation and positioning anti-interference method, system, terminal device, and storage medium, which can effectively solve the problem of inaccurate vehicle navigation and positioning due to interference with GNSS signals.

[0004] In a first aspect, embodiments of this application provide a navigation and positioning anti-interference method, including: Under conditions of signal interference in the vehicle navigation satellite system, real-time vehicle status data is collected, including vehicle speed and engine status. With the engine off, adjust the satellite positioning signal strength to the target signal strength; With the engine running and the vehicle speed less than or equal to a preset speed, the signal strength of the satellite positioning signal is adjusted to the target signal strength, and the satellite positioning deviation is compensated based on the vehicle status data to obtain the target vehicle speed and target vehicle position. When the engine is running and the vehicle speed is greater than a preset speed, narrowband satellite positioning interference signals are suppressed.

[0005] In a first possible embodiment of the first aspect, it further includes: The satellite positioning signal data of the vehicle-mounted navigation satellite system is collected, and the satellite positioning signal data includes signal strength, signal-to-noise ratio, number of visible satellites, and positioning accuracy factor; If the satellite positioning signal data remains within an abnormal range for a preset period of time, it is determined that the vehicle navigation satellite system is experiencing signal interference. In a second possible embodiment of the first aspect, adjusting the signal strength of the satellite positioning signal to the target signal strength includes: Calculate the deviation between the current satellite positioning signal strength and the target signal strength; Based on the deviation value, the gain adjustment of the adjustable gain amplifier at the signal receiver is proportional-integral control to adjust the signal strength to the target signal strength.

[0006] In a third possible embodiment of the first aspect, the vehicle state data further includes acceleration and angular velocity measured by an inertial measurement unit, and the compensation for satellite positioning deviation based on the vehicle state data includes: Based on the acceleration and angular velocity measured by the inertial measurement unit, the current speed and current position of the vehicle are predicted, and the predicted speed and predicted position of the vehicle are obtained. If the error between the predicted vehicle position and the satellite-positioned vehicle position is less than a preset error threshold, the predicted vehicle speed and the predicted vehicle position are corrected by a Kalman filter to obtain the target vehicle speed and the target vehicle position. If the error between the predicted vehicle position and the satellite-positioned vehicle position is greater than a preset error threshold, the predicted vehicle speed is used as the target vehicle speed, and the predicted vehicle position is used as the target vehicle speed.

[0007] In a fourth possible embodiment of the first aspect, the step of predicting the vehicle's current speed and current position based on the acceleration and angular velocity measured by the inertial measurement unit, and obtaining the predicted vehicle speed and predicted vehicle position, includes: The actual vehicle acceleration in the geodetic coordinate system is obtained based on the acceleration and the angular velocity, and the acceleration measured by the inertial measurement unit is the acceleration in the vehicle body coordinate system. The vehicle's current speed is calculated based on the actual vehicle acceleration and the vehicle's initial speed, and the predicted vehicle speed is obtained. The vehicle position change is calculated based on the vehicle's current speed and acceleration, and the vehicle's current position is calculated based on the vehicle position change and the vehicle's initial position to obtain the vehicle's predicted position.

[0008] In a fifth possible embodiment of the first aspect, obtaining the actual vehicle acceleration in the geodetic coordinate system based on the acceleration and the angular velocity includes: The vehicle attitude quaternion is calculated based on the angular velocity, and the vehicle attitude quaternion is converted into a rotation matrix. The rotation matrix is ​​used to transform the acceleration from the vehicle body coordinate system to the earth coordinate system. The vehicle acceleration after coordinate system transformation is obtained based on the rotation matrix. The vehicle acceleration after coordinate system transformation includes the actual vehicle acceleration and gravitational acceleration. Remove the gravitational acceleration from the vehicle acceleration after the coordinate system transformation to obtain the actual vehicle acceleration. In a sixth possible embodiment of the first aspect, after adjusting the signal strength of the satellite positioning signal to the target signal strength, the method further includes: The system detects whether there is signal interference in the vehicle navigation satellite system at first preset time intervals, and performs normal satellite positioning when there is no signal interference in the vehicle navigation satellite system. After compensating for satellite positioning deviations based on the vehicle status data, the method further includes: The vehicle navigation satellite system is checked for signal interference every second preset time interval. If the vehicle navigation satellite system is found to be free of signal interference multiple times in a row, normal satellite positioning is performed. After suppressing narrowband satellite positioning interference signals, the method further includes: Every third preset time interval, the vehicle navigation satellite system is checked for signal interference. If the vehicle navigation satellite system is found to be free of signal interference multiple times in a row, normal satellite positioning is performed. If signal interference is detected in the vehicle-mounted navigation satellite system, the received satellite positioning cache information is cleared by resetting the vehicle-mounted navigation satellite system.

[0009] Secondly, embodiments of this application provide a navigation and positioning anti-interference system, comprising: The data acquisition module is used to collect vehicle status data in real time under the condition of signal interference in the vehicle navigation satellite system. The vehicle status data includes vehicle speed and engine status. The first anti-interference module is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is not running. The second anti-interference module is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is running and the vehicle speed is less than or equal to a preset speed, and to compensate for the satellite positioning deviation based on the vehicle status data to obtain the target vehicle speed and target vehicle position. The third anti-interference module is used to suppress narrowband satellite positioning interference signals when the engine is running and the vehicle speed is greater than a preset speed.

[0010] Thirdly, embodiments of this application provide a terminal device, including a memory and a processor. The memory stores a computer program, and the computer program executes the above-described navigation and positioning anti-interference method when it is run on the processor.

[0011] Fourthly, embodiments of this application provide a readable storage medium storing a computer program that executes the above-described navigation and positioning anti-interference method when run on a processor.

[0012] The embodiments of this application have the following beneficial effects: This embodiment of a navigation and positioning anti-interference method includes: real-time acquisition of vehicle status data, including vehicle speed and engine status, under conditions of signal interference in the vehicle-mounted navigation satellite system; adjusting the signal strength of the satellite positioning signal to a target signal strength when the engine is off; adjusting the signal strength of the satellite positioning signal to the target signal strength when the engine is on and the vehicle speed is less than or equal to a preset speed; compensating for satellite positioning deviations based on the vehicle status data to obtain the target vehicle speed and target vehicle position; and suppressing narrowband satellite positioning interference signals when the engine is on and the vehicle speed is greater than a preset speed. Based on the above scheme, this application can perform differentiated processing when signal interference exists in the vehicle-mounted navigation satellite system, adapting to vehicle scenarios. It formulates a three-level processing strategy based on vehicle speed and engine start-up status, avoiding excessive processing and saving energy when the vehicle is off, and strengthening anti-interference capabilities and ensuring positioning accuracy when driving at high speeds. This achieves on-demand processing, balancing processing effectiveness and system overhead, and meeting the positioning needs of different driving scenarios. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This paper illustrates a first flowchart of a navigation and positioning anti-interference method according to an embodiment of this application. Figure 2 A second flowchart of the navigation and positioning anti-interference method according to an embodiment of this application is shown; Figure 3 A schematic diagram of a navigation and positioning anti-interference system according to an embodiment of this application is shown.

[0015] Explanation of key component symbols: 200 - Navigation and positioning anti-interference system; 210 - Data acquisition module; 220 - First anti-interference module; 230 - Second anti-interference module; 240 - Third anti-interference module. Detailed Implementation

[0016] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0017] The components of the embodiments of this application described and illustrated in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0018] In the following text, the terms "comprising," "having," and their cognates, which may be used in various embodiments of this application, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more combinations thereof. Furthermore, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0019] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be construed as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.

[0020] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0021] Existing navigation and positioning anti-interference methods mostly focus on passive defense measures such as signal filtering and interference source identification. These methods use hardware filtering modules or basic software algorithms to suppress or eliminate detected interference signals to restore GNSS signal reception quality. However, current technologies lack a time threshold judgment mechanism for responding to GNSS interference signals. This easily leads to misjudging transient signal fluctuations (such as transient electromagnetic interference or satellite signal obstruction) as interference, frequently triggering interference processing procedures, resulting in wasted vehicle system resources and potentially causing frequent switching of positioning data, affecting positioning continuity. Furthermore, they fail to develop differentiated interference handling strategies based on the vehicle's dynamic state. For example, when the vehicle is stationary and the engine is off (e.g., parked and engine off), GNSS interference has minimal impact on vehicle functionality and does not require complex recovery procedures. However, when the vehicle is traveling at high speed and the engine is running (e.g., in motion), GNSS interference needs to be processed quickly. Current technologies do not differentiate between these scenarios, resulting in low processing efficiency or wasted resources.

[0022] Therefore, the existing navigation and positioning anti-interference processing procedures lack specificity. Regardless of the vehicle's state, a uniform interference elimination scheme is used, which cannot optimize the processing priority according to the actual usage scenario of the vehicle, and it is difficult to balance the processing effect and system resource consumption.

[0023] To address the aforementioned issues, this application provides a navigation and positioning anti-interference method, system, terminal device, and storage medium. This method accurately identifies signal interference in vehicle-mounted navigation satellite systems, avoiding misjudgments. By setting abnormal time thresholds, it effectively distinguishes between instantaneous signal fluctuations and confirmed interference states, reducing invalid processing steps caused by brief signal blockages and electromagnetic interference, lowering vehicle system resource consumption, and improving the continuity and stability of GNSS positioning data. Furthermore, it can formulate a three-level processing strategy based on vehicle speed and engine start status. When the vehicle is off, it avoids excessive processing and saves energy; when traveling at high speeds, it strengthens anti-interference capabilities and ensures positioning accuracy, achieving "on-demand processing" that balances processing effectiveness and system overhead, meeting the positioning needs of different driving scenarios.

[0024] The following describes the anti-interference method for navigation and positioning using specific examples.

[0025] Figure 1 A flowchart of a navigation and positioning anti-interference method according to an embodiment of this application is shown. Exemplarily, the navigation and positioning anti-interference method includes the following steps: S110 collects vehicle status data in real time, including vehicle speed and engine status, even when there is signal interference with the vehicle navigation satellite system.

[0026] In one embodiment, satellite positioning signal data of the vehicle-mounted navigation satellite system is collected. The satellite positioning signal data includes signal strength, signal-to-noise ratio, number of visible satellites, and position dilution of precision (PDOP). If the satellite positioning signal data remains within an abnormal range for a preset time, it is determined that there is signal interference in the vehicle-mounted navigation satellite system.

[0027] In this embodiment, signal strength refers to the power of the satellite positioning signal received by the GNSS receiver, signal-to-noise ratio represents the ratio of useful satellite signal power to background noise power, visible satellite count represents the number of satellites that can be detected by the GNSS receiver and used for positioning calculation at the current moment, and positioning accuracy factor is used to reflect the degree to which the spatial geometric distribution of satellites weakens the positioning accuracy.

[0028] In one implementation, if the signal strength is lower than a preset strength, the signal-to-noise ratio is lower than a preset signal-to-noise ratio, the number of visible satellites is lower than a preset number, or the positioning accuracy factor is greater than a preset positioning accuracy factor, it is preliminarily determined that there is suspected signal interference, and the start timestamp of the presence of signal interference is recorded simultaneously. The preset strength can be set to -130dBm, the preset signal-to-noise ratio to 10dB, the preset number of satellites to 4, and the preset positioning accuracy factor to 5. In another implementation, the duration of suspected signal interference is monitored to determine if a preset time has been reached. Based on the recorded start timestamp of signal interference, the continuous duration of the suspected interference state is continuously counted: if the continuous duration does not reach the preset time, and the signal data recovers to the normal range during this period (i.e., signal strength greater than or equal to a preset strength, signal-to-noise ratio greater than or equal to a preset signal-to-noise ratio, number of visible satellites greater than or equal to a preset number, and positioning accuracy factor less than or equal to a preset positioning accuracy factor), then it is determined to be an instantaneous signal fluctuation, the suspected interference record is cleared, and monitoring for signal interference continues. If the continuous duration of signal interference exceeds the preset time, and the satellite positioning signal data remains within the abnormal range, then signal interference is determined to exist in the vehicle navigation satellite system, triggering the subsequent vehicle status data collection process. The preset time can be set to 120 seconds.

[0029] In this embodiment, by setting a multi-parameter joint judgment mechanism and combining it with a preset time threshold for continuous verification, it is possible to effectively distinguish between instantaneous signal fluctuations and real GNSS interference events, avoiding false triggering caused by brief obstructions or electromagnetic noise. This significantly improves the accuracy of interference identification and the stability of system operation, while providing a reliable decision-making basis for subsequent differentiated processing strategies based on vehicle operating status.

[0030] As an example, vehicle status data can be obtained via the onboard CAN (Controller Area Network) bus. Vehicle speed is obtained from the wheel speed sensors of the vehicle's ABS (Anti-lock Braking System). Engine status is obtained from the engine controller, represented by binary signals indicating start or stop. The acquisition frequency of vehicle status data is consistent with the acquisition frequency of satellite positioning signal data to ensure data time synchronization and avoid judgment errors caused by time differences.

[0031] S120 adjusts the signal strength of the satellite positioning signal to the target signal strength when the engine is not running.

[0032] In one embodiment, the engine is in an off state. At this time, the vehicle speed is not considered, and the vehicle is determined to be in a parked and off state. The signal interference of the vehicle navigation satellite system has no direct impact on the vehicle's driving function. A mild processing strategy is activated, which adjusts the signal strength of the satellite positioning signal only by adjusting the GNSS signal receiving gain to enhance the weak signal acquisition capability.

[0033] In one embodiment, adjusting the signal strength of a satellite positioning signal to a target signal strength includes: calculating the deviation between the current signal strength of the satellite positioning signal and the target signal strength; and performing proportional-integral control on the gain adjustment of an adjustable gain amplifier at the signal receiver based on the deviation to adjust the signal strength to the target signal strength.

[0034] In this embodiment, by monitoring the signal strength of the received satellite positioning signal in real time, the gain of the GNSS signal receiver's RF front-end is dynamically adjusted to achieve an adaptive control strategy that enhances weak signals and prevents saturation of strong signals. Its core is to construct a closed-loop logic for signal acquisition, deviation calculation, and gain adjustment through a closed-loop feedback algorithm, ensuring that the satellite positioning signal remains stable and trackable even in complex environments such as obstruction, interference, and direct sunlight.

[0035] In one embodiment, a target signal strength range is set, such as -120dBm to -90dBm. Within this range, the signal will not be lost due to excessive weakness, nor will it saturate the amplifier due to excessive strength. When the satellite positioning signal is less than -120dBm, i.e., a weak signal, the gain of the adjustable gain amplifier is increased, for example, by adjusting it by 3 to 5dB each time, in a step-wise manner to avoid abrupt changes. When the satellite positioning signal is greater than -90dBm, i.e., a strong signal, the gain of the adjustable gain amplifier is decreased, for example, by adjusting it by 2 to 3dB each time, in a smooth adjustment to prevent signal distortion.

[0036] The formula for calculating the signal strength of satellite positioning signals during signal acquisition is as follows:

[0037] For the first The signal strength of the satellite positioning signal during the second signal sampling. Represented as the first The signal power of the next signal sample. For reference power, .

[0038] In deviation calculation, the formula for calculating the deviation value is:

[0039] This is the deviation between the signal strength of the satellite positioning signal and the target signal strength. It is used to define the deviation between the current signal strength and the target signal strength, and to quantify the degree to which the signal deviates from the ideal state. The target signal strength. If If the signal strength is lower than the target signal strength, the current satellite positioning signal is weak and the gain needs to be increased; if If the signal strength is higher than the target signal strength, then the current satellite positioning signal is a strong signal and the gain needs to be reduced.

[0040] In gain adjustment, the gain adjustment amount of the adjustable gain amplifier is calculated using proportional-integral (PI) control based on the deviation value, taking into account both response speed and stability. The formula for calculating the gain adjustment amount is as follows:

[0041] This indicates the gain adjustment amount of the adjustable gain amplifier. This represents the proportionality coefficient, which determines the speed of response to the current deviation. The larger the size, the more sensitive the adjustment. The range can be set from 0.2 to 0.5. . This represents the integral coefficient, which accumulates historical deviations to eliminate steady-state errors, such as in scenarios with persistent weak signals. The range can be set from 0.01 to 0.1. , Indicates the sampling period of the satellite positioning signal. The value range can be set from 0.01 to 0.1 s. This setting limits the gain adjustment of the adjustable gain amplifier to prevent sudden gain changes or exceeding limits. That is, the maximum value of the gain adjustment is The minimum value is -5.

[0042] The RF front-end of a GNSS receiver includes an adjustable gain amplifier with dynamically adjustable gain. Gain adjustment is achieved by controlling the adjustable gain amplifier, which includes a low-noise amplifier (LNA) and a variable gain amplifier (VGA). Gain control commands can be sent to the LNA and VGA via a communication interface, such as adjusting the LNA gain by 20dB and the VGA gain by 15dB. This communication interface includes, but is not limited to, SPI (Serial Peripheral Interface) and I²C (Inter-Integrated Circuit). The LNA is located at the very beginning of the receiver link and is responsible for amplifying weak signals. The LNA gain adjustment range is 0~30dB, with an extremely low noise figure to avoid introducing additional noise. The LNA gain should be increased for weak signals and decreased for strong signals. The variable gain amplifier, located after the low-noise amplifier, can be continuously adjusted via digital commands. The gain adjustment range of the variable gain amplifier is 0~40dB, which is used to finely adjust the signal amplitude and ensure that the signal strength of the GNSS signal is within the optimal range.

[0043] In one embodiment, after adjusting the signal strength of the satellite positioning signal to the target signal strength, the method further includes: detecting whether there is signal interference in the vehicle navigation satellite system every first preset time interval; and performing normal satellite positioning if there is no signal interference in the vehicle navigation satellite system. In this embodiment, the first preset time interval can be set to 30 seconds, and the signal status is re-detected every 30 seconds. If the signal returns to normal, the signal strength adjustment is terminated.

[0044] S130, with the engine running and the vehicle speed less than or equal to a preset speed, adjusts the signal strength of the satellite positioning signal to the target signal strength, and compensates for the satellite positioning deviation based on the vehicle status data to obtain the target vehicle speed and target vehicle position.

[0045] In this embodiment, when the engine is running, the vehicle speed is further subdivided. For example, the preset speed can be set to 5 km / h. When the vehicle is in a low-speed driving or idling state, a medium-level processing strategy is activated. That is, in addition to the signal strength of the satellite positioning signal, short-term data fusion of GNSS and vehicle status data is activated. The vehicle status data is used to compensate for GNSS positioning deviation and improve positioning accuracy.

[0046] For example, vehicle state data also includes acceleration and angular velocity measured by an Inertial Measurement Unit (IMU), which includes an accelerometer and a gyroscope. The accelerometer is used to measure acceleration, and the gyroscope is used to measure angular velocity. The angular velocity and acceleration output by the IMU reflect the vehicle's rotation about three-dimensional axes.

[0047] In one embodiment, such as Figure 2 As shown, compensating for satellite positioning deviations based on vehicle status data specifically includes the following steps: S131, based on the acceleration and angular velocity measured by the inertial measurement unit, predict the current speed and current position of the vehicle, and obtain the predicted speed and predicted position of the vehicle.

[0048] Exemplary of this application, it utilizes acceleration and angular velocity data measured by an IMU to predict vehicle speed and position. The core of this method is to use a dead reckoning algorithm to calculate vehicle speed and position using high-frequency dynamic data from the IMU when GNSS signals are blocked, interfered with, or drifted, thus filling gaps in GNSS positioning or correcting its errors. The dead reckoning algorithm uses the IMU's acceleration and angular velocity data to calculate the vehicle's position, speed, and attitude through integration.

[0049] In one embodiment, the actual vehicle acceleration in the geodetic coordinate system is obtained based on acceleration and angular velocity, while the acceleration measured by the inertial measurement unit (IMU) is the acceleration in the vehicle body coordinate system. The vehicle body coordinate system is a three-dimensional Cartesian coordinate system fixed on the vehicle, moving and rotating with it. The outputs of the accelerometer and gyroscope are based on this coordinate system. The geodetic coordinate system is a navigation coordinate system fixed to the earth, and GNSS and IMU fusion must be based on this coordinate system.

[0050] The gyroscope output is a discrete-time series. A quaternion update formula is used to represent the vehicle's attitude state relative to the ground coordinate system, adapting to real-time updates of discrete sampling and coordinate system transformations. The quaternion update formula is:

[0051] This represents the vehicle's attitude state relative to the Earth's coordinate system at time k, i.e., the vehicle attitude quaternion. express The attitude state of the vehicle relative to the ground coordinate system at any given time. The sampling interval represents the interval from... Time's up The time elapsed since the beginning of the moment This represents the pure imaginary quaternion corresponding to angular velocity. Indicates the first Vehicle orbiting the body coordinate system at all times angular velocity of the axis, Indicates the first Vehicle orbiting the body coordinate system at all times angular velocity of the axis, Indicates the first Vehicle orbiting the body coordinate system at all times Angular velocity of the axis.

[0052] In one embodiment, the vehicle attitude quaternion is calculated based on angular velocity, and then converted into a rotation matrix. This rotation matrix is ​​used to transform the acceleration from the vehicle body coordinate system to the ground coordinate system. In this embodiment, the calculated vehicle attitude quaternion can be normalized, and then the rotation matrix can be obtained using the rotation matrix formula:

[0053] Let the rotation matrix be represented by the attitude quaternion. , It is a real scalar. Each is a virtual part, and each is bound to a different mech. The axis, along with the other three elements, together constitute the unit quaternion. It uniquely and without oddity represents the vehicle's attitude.

[0054] In another embodiment, the vehicle acceleration after coordinate system transformation is obtained based on the rotation matrix. The vehicle acceleration after coordinate system transformation includes the actual vehicle acceleration and gravitational acceleration. The gravitational acceleration in the vehicle acceleration after coordinate system transformation is removed to obtain the actual vehicle acceleration.

[0055] In this embodiment, the acceleration output by the accelerometer is the specific force in the body coordinate system, which includes gravity. It needs to be transformed to the ground coordinate system first through a rotation matrix, and then the gravitational acceleration is subtracted to obtain the actual vehicle acceleration. The formula for calculating the actual vehicle acceleration is as follows:

[0056] For actual vehicle acceleration, This indicates the acceleration output by the accelerometer. It represents the acceleration due to gravity.

[0057] In one embodiment, the vehicle's current speed is calculated based on the actual vehicle acceleration and the vehicle's initial speed to obtain the vehicle's predicted speed; the vehicle's position change is calculated based on the vehicle's current speed and vehicle acceleration, and the vehicle's current position is calculated based on the vehicle's position change and the vehicle's initial position to obtain the vehicle's predicted position.

[0058] In this embodiment, the formula for calculating the predicted vehicle speed is:

[0059] Indicates in Predicted vehicle speed at any given time. Indicates in Predicted vehicle speed at any given time. Indicates in The actual vehicle acceleration at time t, where the initial velocity is... Provided by GNSS.

[0060] Integrating the velocity yields the position change in the geodetic coordinate system, which is then superimposed to obtain the predicted vehicle position. The formula for calculating the position change is:

[0061] in, In order to be in Change in position at any given moment; The formula for calculating the predicted vehicle position is:

[0062] Indicates the predicted location of the vehicle. Indicates in Predicted vehicle position at time, initial vehicle position It can be provided by GNSS.

[0063] S132, under the condition that the error between the vehicle's predicted position and the vehicle's position determined by satellite positioning is less than a preset error threshold, the predicted vehicle speed and predicted vehicle position are corrected by a Kalman filter to obtain the target vehicle speed and target vehicle position.

[0064] S133, when the error between the vehicle's predicted position and the vehicle's position determined by satellite positioning is greater than a preset error threshold, the vehicle's predicted speed and the vehicle's predicted position are used as the target vehicle speed. The two data can be fused using a Kalman filter to obtain the target vehicle speed and the target vehicle position.

[0065] In one embodiment, the Kalman filter includes, but is not limited to, an Extended Kalman Filter (EKF) and an Unscented Kalman Filter (UKF). A preset error threshold can be set to 5m. If the error between the predicted vehicle position and the satellite-positioned vehicle position is small and less than the preset error threshold, the GNSS-positioned vehicle position and speed are used as observations to correct the calculated predicted vehicle speed and position, thus compensating for the calculation error. If the error between the predicted vehicle position and the satellite-positioned vehicle position is large, the GNSS-positioned vehicle position and speed are no longer used as observations; only the dead reckoning-based predicted vehicle speed and position are used as output until GNSS is restored.

[0066] In one implementation, taking extended Kalman filtering as an example, an initial state vector is established, which includes the vehicle's predicted position, vehicle's predicted velocity, attitude quaternion, and IMU bias.

[0067] in, Represents the state vector. Indicates the predicted location of the vehicle. Indicates the predicted speed of the vehicle. This indicates the accelerometer's zero bias, i.e., its error. This indicates that the gyroscope has zero bias, i.e., error. The state vector simultaneously contains the vehicle's motion state and the sensor error state. The extended Kalman filter estimates the zero bias in real time through a fusion process, correcting the predicted vehicle speed and position, and reducing drift. First, the state vector is updated based on IMU data:

[0068] express The state vector estimated from the prior state at time t. No. The state vector of the posterior state estimation at the previous time step is the optimal state vector corrected based on GNSS observations at the previous time step, including the target vehicle position and target vehicle speed at the previous time step. This represents the state transition function, which describes the mathematical relationship between the previous state and the current state. This represents the original measurement value of the gyroscope.

[0069] Finally, based on the correction of the predicted values ​​using GNSS observations, the optimal estimate is obtained:

[0070] express GNSS observation vector at time, This indicates the vehicle's location as determined by GNSS positioning. This indicates the vehicle speed as determined by GNSS positioning. express The state vector of the posterior state estimate at time t, including The target vehicle's position and speed at any given time. This represents the Kalman gain at time k. This represents the observation model function, used to convert the state vector estimated from the prior state into predicted GNSS observations; that is, if the prior state is accurate, the GNSS should observe the values. This represents the difference between the actual GNSS observation and the predicted value.

[0071] In one embodiment, after compensating for satellite positioning deviation based on vehicle status data, the method further includes: detecting whether there is signal interference in the vehicle navigation satellite system every second preset time interval; and performing normal satellite positioning if signal interference is not detected in the vehicle navigation satellite system multiple times consecutively. In this embodiment, the second preset time interval can be set to 15 seconds. For example, if the signal is detected to be normal three times consecutively, the satellite positioning deviation is compensated, and the system returns to normal GNSS positioning mode.

[0072] S140 suppresses narrowband satellite positioning interference signals when the engine is running and the vehicle speed is greater than a preset speed.

[0073] In one implementation, if the vehicle speed exceeds a preset speed and the vehicle is currently in normal driving mode, a heavy-duty processing strategy is initiated, immediately activating a hardware anti-interference module, such as an adaptive notch filter, to suppress narrowband satellite positioning interference signals. Narrowband satellite positioning interference signals refer to unwanted radio frequency signals with a frequency bandwidth less than a preset threshold (e.g., less than 100 kHz) and high energy, including continuous wave interference introduced by onboard power electronic devices, motor brush noise, or external radio frequency emission sources. Such interference manifests as significant power peaks within local frequency bands in the frequency domain, easily leading to receiver front-end saturation or a decrease in signal-to-noise ratio.

[0074] In another embodiment, after suppressing narrowband satellite positioning interference signals, the method further includes: detecting whether there is signal interference in the vehicle navigation satellite system every third preset time interval; performing normal satellite positioning if no signal interference is detected in the vehicle navigation satellite system multiple times in a row; and clearing the received satellite positioning cache information by resetting the vehicle navigation satellite system if signal interference is still detected in the vehicle navigation satellite system.

[0075] In this embodiment, the third preset time can be set to 10 seconds. For example, the signal status can be detected continuously for 10 seconds. If the signal returns to normal after 5 consecutive detections, the hardware anti-interference module is gradually shut down to avoid excessive consumption of vehicle power and computing resources. If it still cannot return to normal working mode, a GNSS soft reset operation is performed to clear the satellite cache information received in the module and prevent abnormal states caused by GNSS operation.

[0076] Figure 3 A schematic diagram of a navigation and positioning anti-interference system 200 according to an embodiment of this application is shown. Exemplarily, the navigation and positioning anti-interference system 200 includes: The data acquisition module 210 is used to collect vehicle status data in real time under the condition that there is signal interference in the vehicle navigation satellite system. The vehicle status data includes vehicle speed and engine status.

[0077] The first anti-interference module 220 is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is not started.

[0078] The second anti-interference module 230 is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is running and the vehicle speed is less than or equal to the preset speed, and to compensate for the satellite positioning deviation based on the vehicle status data to obtain the target vehicle speed and target vehicle position.

[0079] The third anti-interference module 240 is used to suppress narrowband satellite positioning interference signals when the engine is running and the vehicle speed is greater than a preset speed.

[0080] It is understood that the system in this embodiment corresponds to the satellite positioning anti-interference method in the above embodiments, and the options in the above embodiments are also applicable to this embodiment, so they will not be described again here.

[0081] This application also provides a terminal device, exemplary of which includes, but is not limited to, vehicle positioning devices, vehicle navigation terminals, and autonomous driving domain controllers. The terminal device includes a processor and a memory, wherein the memory stores a computer program, and the processor executes the computer program to enable the terminal device to perform the functions of the aforementioned satellite positioning anti-interference method or the various modules in the aforementioned satellite positioning anti-interference system.

[0082] The processor can be an integrated circuit chip with signal processing capabilities. The processor can be a general-purpose processor, including at least one of a Central Processing Unit (CPU), Graphics Processing Unit (GPU), Network Processor (NP), Digital Signal Processor (DSP), Application-Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The general-purpose processor can be a microprocessor or any conventional processor, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this application.

[0083] The memory can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory is used to store computer programs, and the processor can execute the computer programs accordingly after receiving execution instructions.

[0084] This application also provides a computer-readable storage medium for storing the computer program used in the aforementioned terminal device. For example, the computer-readable storage medium may include, but is not limited to, various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0085] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, in alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0086] In addition, the functional modules or units in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0087] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0088] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A navigation and positioning anti-interference method, characterized in that, include: Under conditions of signal interference in the vehicle navigation satellite system, real-time vehicle status data is collected, including vehicle speed and engine status. With the engine off, adjust the satellite positioning signal strength to the target signal strength; With the engine running and the vehicle speed less than or equal to a preset speed, the signal strength of the satellite positioning signal is adjusted to the target signal strength, and the satellite positioning deviation is compensated based on the vehicle status data to obtain the target vehicle speed and target vehicle position. When the engine is running and the vehicle speed is greater than a preset speed, narrowband satellite positioning interference signals are suppressed.

2. The navigation and positioning anti-interference method according to claim 1, characterized in that, Also includes: The satellite positioning signal data of the vehicle-mounted navigation satellite system is collected, and the satellite positioning signal data includes signal strength, signal-to-noise ratio, number of visible satellites, and positioning accuracy factor; If the satellite positioning signal data remains within an abnormal range for a preset period of time, it is determined that the vehicle navigation satellite system is experiencing signal interference.

3. The navigation and positioning anti-interference method according to claim 1, characterized in that, Adjusting the signal strength of the satellite positioning signal to the target signal strength includes: Calculate the deviation between the current satellite positioning signal strength and the target signal strength; Based on the deviation value, the gain adjustment of the adjustable gain amplifier at the signal receiver is proportional-integral control to adjust the signal strength to the target signal strength.

4. The navigation and positioning anti-interference method according to claim 1, characterized in that, The vehicle status data also includes acceleration and angular velocity measured by the inertial measurement unit. The compensation for satellite positioning deviation based on the vehicle status data includes: Based on the acceleration and angular velocity measured by the inertial measurement unit, the current speed and current position of the vehicle are predicted, and the predicted speed and predicted position of the vehicle are obtained. If the error between the predicted vehicle position and the satellite-positioned vehicle position is less than a preset error threshold, the predicted vehicle speed and the predicted vehicle position are corrected by a Kalman filter to obtain the target vehicle speed and the target vehicle position. If the error between the predicted vehicle position and the satellite-positioned vehicle position is greater than a preset error threshold, the predicted vehicle speed is used as the target vehicle speed, and the predicted vehicle position is used as the target vehicle speed.

5. The navigation and positioning anti-interference method according to claim 4, characterized in that, The process of predicting the vehicle's current speed and position based on the acceleration and angular velocity measured by the inertial measurement unit, and obtaining the predicted vehicle speed and position, includes: The actual vehicle acceleration in the geodetic coordinate system is obtained based on the acceleration and the angular velocity, and the acceleration measured by the inertial measurement unit is the acceleration in the vehicle body coordinate system. The vehicle's current speed is calculated based on the actual vehicle acceleration and the vehicle's initial speed, and the predicted vehicle speed is obtained. The vehicle position change is calculated based on the vehicle's current speed and acceleration, and the vehicle's current position is calculated based on the vehicle position change and the vehicle's initial position to obtain the vehicle's predicted position.

6. The navigation and positioning anti-interference method according to claim 5, characterized in that, The process of obtaining the actual vehicle acceleration in the geodetic coordinate system based on the acceleration and the angular velocity includes: The vehicle attitude quaternion is calculated based on the angular velocity, and the vehicle attitude quaternion is converted into a rotation matrix. The rotation matrix is ​​used to transform the acceleration from the vehicle body coordinate system to the earth coordinate system. The vehicle acceleration after coordinate system transformation is obtained based on the rotation matrix. The vehicle acceleration after coordinate system transformation includes the actual vehicle acceleration and gravitational acceleration. Remove the gravitational acceleration from the vehicle acceleration after the coordinate system transformation to obtain the actual vehicle acceleration.

7. The navigation and positioning anti-interference method according to claim 1, characterized in that, After adjusting the signal strength of the satellite positioning signal to the target signal strength, the method further includes: The system detects whether there is signal interference in the vehicle navigation satellite system at first preset time intervals, and performs normal satellite positioning when there is no signal interference in the vehicle navigation satellite system. After compensating for satellite positioning deviations based on the vehicle status data, the method further includes: The vehicle navigation satellite system is checked for signal interference every second preset time interval. If the vehicle navigation satellite system is found to be free of signal interference multiple times in a row, normal satellite positioning is performed. After suppressing narrowband satellite positioning interference signals, the method further includes: Every third preset time interval, the vehicle navigation satellite system is checked for signal interference. If the vehicle navigation satellite system is found to be free of signal interference multiple times in a row, normal satellite positioning is performed. If signal interference is detected in the vehicle-mounted navigation satellite system, the received satellite positioning cache information is cleared by resetting the vehicle-mounted navigation satellite system.

8. A navigation and positioning anti-interference system, characterized in that, include: The data acquisition module is used to collect vehicle status data in real time under the condition of signal interference in the vehicle navigation satellite system. The vehicle status data includes vehicle speed and engine status. The first anti-interference module is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is not running. The second anti-interference module is used to adjust the signal strength of the satellite positioning signal to the target signal strength when the engine is running and the vehicle speed is less than or equal to a preset speed, and to compensate for the satellite positioning deviation based on the vehicle status data to obtain the target vehicle speed and target vehicle position. The third anti-interference module is used to suppress narrowband satellite positioning interference signals when the engine is running and the vehicle speed is greater than a preset speed.

9. A terminal device, characterized in that, It includes a memory and a processor, the memory storing a computer program, which, when executed on the processor, performs the navigation and positioning anti-interference method according to any one of claims 1 to 7.

10. A readable storage medium, characterized in that, It stores a computer program that, when run on a processor, executes the navigation and positioning anti-interference method according to any one of claims 1 to 7.

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