Satellite navigation velocity measurement method, system and application based on troposphere delay dynamic error correction

Abstract

The application relates to a satellite navigation velocity measurement method, system and application based on a dynamic error correction of a troposphere delay, and belongs to the technical field of satellite navigation velocity measurement. The method comprises the following steps: inputting receiver elevation and vertical velocity obtained through least square calculation and velocity measurement calculation into a troposphere delay empirical model to calculate a troposphere delay change rate, converting the troposphere delay change rate into Doppler frequency shift error information, correcting Doppler frequency shift for calculation, and performing least square iteration again, so that accurate velocity measurement results are obtained. The method can accurately quantify and correct inherent system errors introduced by the troposphere delay change rate in real time, and fundamentally improves the satellite velocity measurement precision in a high dynamic scene while maintaining a high data rate.

Description

Technical Field

[0001] This application relates to the field of satellite navigation velocity measurement technology, and in particular to a satellite navigation velocity measurement method, system and application based on tropospheric delay dynamic error correction. Background Technology

[0002] The velocity measurement function of Global Navigation Satellite Systems (GNSS) relies heavily on Doppler shift observations, which directly characterize the signal frequency shift caused by the relative radial motion between the satellite and the receiver. However, when high-speed moving vehicles (such as reentry vehicles and high-performance UAVs) experience significant vertical displacement, the rapid change in their elevation causes a dynamic alteration in the tropospheric delay along the satellite navigation signal propagation path. This alteration directly introduces a non-geometric Doppler shift system error, significantly impacting velocity measurement accuracy.

[0003] To address the velocity measurement error caused by rapid changes in tropospheric delay in highly dynamic scenarios, the most representative existing technical solution is to compress the Doppler integration time. The design logic of this solution is to reduce the accumulation of tropospheric delay change rate and other dynamic errors within a single observation period by shortening the integration time, thereby reducing the sensitivity of the velocity calculation results to dynamic errors. However, this solution has significant technical limitations, specifically in two aspects:

[0004] First, compressing the integration time only weakens the error smoothing effect within a single observation; it does not fundamentally eliminate the systematic error caused by the tropospheric delay rate of change. This type of error will still persist in every set of Doppler shift observations. Second, according to fundamental signal processing theory, the signal-to-noise ratio (SNR) of Doppler shift observations is positively correlated with the square root of the integration time. Significantly compressing the integration time directly leads to a significant increase in the noise level of the observations, which is equivalent to introducing a larger random error in order to suppress one type of systematic error. In this case, although compressing the integration time increases the data rate, velocity calculation based on high-noise observations will cause increased jitter in the calculation results, ultimately leading to a technical contradiction where the overall accuracy of velocity measurement decreases instead of increasing. Summary of the Invention

[0005] Therefore, it is necessary to provide a satellite navigation velocity measurement method, system, and application based on tropospheric delay dynamic error correction to address the aforementioned technical problems. This method can fundamentally model and eliminate the systematic error of the tropospheric delay rate of change, thereby improving the accuracy of satellite navigation velocity measurement in highly dynamic scenarios while maintaining a high data rate.

[0006] A satellite navigation velocity measurement method based on tropospheric delay dynamic error correction, the method comprising:

[0007] The original observation information, which includes the original Doppler frequency shift, acquired by the navigation receiver is corrected to obtain the corrected observation information. Based on the corrected observation information, least squares and velocity calculations are performed to obtain the elevation of the navigation receiver. and vertical velocity ;

[0008] Using the empirical model of tropospheric delay, the delay of each satellite was calculated. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite.

[0009] The corrected Doppler frequency shift is recorrected based on the Doppler frequency shift error to obtain the recorrected Doppler frequency shift.

[0010] Based on the recalibrated Doppler frequency shift, the velocity is calculated again to obtain the accurate velocity information of the navigation receiver.

[0011] In one embodiment, the original observation information acquired by the navigation receiver, which includes the original Doppler frequency shift, is corrected to obtain corrected observation information, including:

[0012] Using the raw observation information, including the raw pseudorange and raw Doppler shift, obtained from the baseband of the navigation receiver, and the ephemeris information obtained from the raw message, the satellite position, satellite velocity, satellite clock error, and satellite frequency difference are calculated for each satellite. The raw pseudorange is then corrected based on ionospheric delay information and tropospheric delay information to obtain the corrected pseudorange. Finally, the raw Doppler shift is corrected using the satellite frequency difference to obtain the corrected Doppler shift.

[0013] In one embodiment, the original Doppler frequency shift is corrected using the satellite frequency difference, resulting in the corrected Doppler frequency shift, expressed as:

[0014] ;

[0015] in, It is the first Doppler shift corrected for each satellite; It is the first The raw Doppler frequency shift obtained from satellite measurements; It is the satellite frequency offset; This is the nominal frequency of the current satellite signal.

[0016] In one embodiment, least squares calculation and velocity measurement calculation are performed based on the corrected observation information to obtain the elevation of the navigation receiver. and vertical velocity ,include:

[0017] The position information of the navigation receiver is obtained by performing least-squares calculation using satellite position and corrected pseudorange, and the longitude of the navigation receiver is obtained by performing latitude-longitude-altitude conversion. ,latitude and elevation ;

[0018] Using the position information of the navigation receiver, satellite velocity, and the corrected Doppler frequency shift, velocity calculation is performed to obtain the initial velocity information of the navigation receiver, expressed as:

[0019] ;

[0020] in, This represents the initial velocity of the navigation receiver in the ECEF coordinate system. for Three-dimensional velocity components in the ECEF coordinate system; The speed of light; It is the first Doppler shift corrected for each satellite; This is the nominal frequency of the current satellite signal; To point from the navigation receiver to the first The unit direction vector of a satellite; For the first The velocity of the satellite in ECEF coordinates;

[0021] By using the initial velocity in the ECEF coordinate system Perform a coordinate transformation to obtain the initial velocity of the navigation receiver in the ENU coordinate system. ; These represent the eastward velocity, the northward velocity, and the upward velocity, respectively, with the upward velocity also known as the vertical velocity.

[0022] In one embodiment, the empirical model for tropospheric delay is either the Saastamoinen model or the Hopfield model.

[0023] In one embodiment, an empirical model of tropospheric delay is used to calculate the delay of each satellite. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite, including:

[0024] Using the Saastamoinen model, calculate the first... A satellite in and The tropospheric delays at the locations are respectively and ;in, The elevation of the navigation receiver. The vertical velocity of the navigation receiver;

[0025] right and Find the difference to get the first... The rate of change of tropospheric delay for each satellite And convert it to obtain the first tropospheric delay caused by the change in tropospheric delay. The Doppler frequency shift error of the satellite is ;in, The nominal frequency of the current satellite signal. It is the speed of light.

[0026] In one embodiment, the corrected Doppler frequency shift is recorrected based on the Doppler frequency shift error to obtain the recorrected Doppler frequency shift, including:

[0027] The first caused by tropospheric delay variation Doppler frequency shift error of each satellite Added in Doppler shift corrected for each satellite Up, get the first The Doppler frequency shift of each satellite after recalibration is expressed as .

[0028] In one embodiment, the velocity measurement is performed again based on the recalibrated Doppler frequency shift to obtain the accurate velocity information of the navigation receiver, including:

[0029] Based on the Doppler shift of satellite recalibration The speed measurement and calculation were performed again to obtain the accurate speed information of the navigation receiver, which is represented as follows:

[0030] ;

[0031] in, This represents the precise velocity of the navigation receiver in the ECEF coordinate system. for Three-dimensional velocity components in the ECEF coordinate system; The speed of light; This is the nominal frequency of the current satellite signal; To point from the navigation receiver to the first The unit direction vector of a satellite; For the first The velocity of the satellite in ECEF coordinates.

[0032] A satellite navigation velocity measurement system based on tropospheric delay dynamic error correction, the system comprising:

[0033] The standard position and velocity calculation module is used to correct the raw observation information acquired by the navigation receiver, which includes the original Doppler frequency shift, to obtain the corrected observation information. Based on the corrected observation information, least squares calculation and velocity measurement are performed to obtain the elevation of the navigation receiver. and vertical velocity ;

[0034] The Doppler frequency shift error calculation module is used to calculate the Doppler frequency shift error of each satellite using an empirical model of tropospheric delay. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite.

[0035] The Doppler frequency shift recorrection module is used to recorrect the corrected Doppler frequency shift based on the Doppler frequency shift error, and obtain the recorrected Doppler frequency shift.

[0036] The precise velocity calculation module is used to perform velocity calculation again based on the recalibrated Doppler frequency shift to obtain the precise velocity information of the navigation receiver.

[0037] A high-speed moving vehicle includes a navigation receiver mounted on the high-speed moving vehicle; the vertical speed of the high-speed moving vehicle is greater than a preset threshold, and the navigation receiver applies the above-mentioned satellite navigation velocity measurement method based on tropospheric delay dynamic error correction to obtain accurate velocity information.

[0038] The aforementioned satellite navigation velocity measurement method, system, and application based on tropospheric delay dynamic error correction have the following advantages compared to existing technologies:

[0039] 1. Creatively using the vertical velocity and elevation of the navigation receiver to calculate and eliminate the Doppler frequency shift error caused by the dynamic changes in tropospheric delay, accurately deducting the error source itself from the physical root, rather than merely trying to mitigate its influence, thus obtaining more accurate and less biased velocity measurement results both theoretically and practically.

[0040] 2. Without compressing the integration time, the high signal-to-noise ratio observations brought about by long integration can be fully utilized, effectively suppressing random noise and making the speed calculation results smoother and more reliable.

[0041] 3. Because the systematic error is effectively deducted and the noise of the observation value is low, the sensitivity of the entire velocity calculation process to the observation geometry and vehicle maneuvering is reduced, and the velocity measurement results are more stable and robust. Attached Figure Description

[0042] Figure 1This is a flowchart illustrating a satellite navigation velocity measurement method based on tropospheric delay dynamic error correction in one embodiment.

[0043] Figure 2 This is a block diagram of a satellite navigation velocity measurement system based on tropospheric delay dynamic error correction in one embodiment. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0045] In one embodiment, such as Figure 1 As shown, a satellite navigation velocity measurement method based on tropospheric delay dynamic error correction is provided, including the following steps:

[0046] Step 1, Calculate Elevation and Vertical Velocity: Correct the original observation information acquired by the navigation receiver, which includes the original Doppler frequency shift, to obtain the corrected observation information. Then, perform least squares calculation and velocity measurement based on the corrected observation information to obtain the elevation of the navigation receiver. and vertical velocity Specifically, step 1 includes:

[0047] Step 1.1: Calculate satellite position, satellite velocity, pseudorange correction, and Doppler shift correction.

[0048] Using raw observation information, including the raw pseudorange and raw Doppler shift, acquired from the navigation receiver baseband, and ephemeris information obtained from the raw messages, satellite position, velocity, clock bias, and frequency offset are calculated for each satellite. The raw pseudorange is then corrected based on ionospheric and tropospheric delay information to obtain the corrected pseudorange. Finally, the raw Doppler shift is corrected using the satellite frequency offset to obtain the corrected Doppler shift. The Doppler shift correction is expressed as:

[0049] ;

[0050] in, It is the first Doppler shift corrected for each satellite, in units of ; It is the first The raw Doppler frequency shift obtained from satellite measurements, in units of ; It is the satellite frequency offset, measured in seconds (s / s). The nominal frequency of the current satellite signal, in units of .

[0051] Step 1.2: Calculate the position of the navigation receiver and obtain the elevation. .

[0052] The position information of the navigation receiver is obtained by performing least-squares calculation using satellite position and corrected pseudorange, and the longitude of the navigation receiver is obtained by performing latitude-longitude-altitude conversion. ,latitude and elevation .

[0053] Step 1.3: Calculate the navigation receiver speed and obtain the vertical velocity. .

[0054] First, using the position information of the navigation receiver, satellite velocity, and the corrected Doppler frequency shift, velocity calculation is performed to obtain the initial velocity information of the navigation receiver, expressed as:

[0055] ;

[0056] in, This represents the initial velocity of the navigation receiver in the ECEF (Earth-centered Earth-fixed) coordinate system. for Three-dimensional velocity components in the ECEF coordinate system, in m / s; The speed of light; It is the first Doppler shift corrected for each satellite; This is the nominal frequency of the current satellite signal; To point from the navigation receiver to the first The unit direction vector of a satellite; For the first The velocity of the satellite in ECEF coordinates, in m / s.

[0057] Furthermore, by adjusting the initial velocity in the ECEF coordinate system Perform coordinate transformation to obtain the initial velocity of the navigation receiver in the ENU (North-South) coordinate system. ; These represent the eastward velocity, the northward velocity, and the upward velocity, respectively, with the upward velocity also known as the vertical velocity.

[0058] Step 2, calculate the Doppler frequency shift error caused by tropospheric delay variation for each satellite: using the empirical model of tropospheric delay, calculate the Doppler frequency shift error caused by tropospheric delay variation for each satellite. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite.

[0059] Empirical models for tropospheric delay can be either the Saastamoinen model or the Hopfield model. The Saastamoinen model is a mathematical model used to estimate tropospheric delay corrections. It is based on empirical formulas for parameters such as water vapor content, air pressure, and temperature in the troposphere and is used for estimating and correcting tropospheric delays in applications such as satellite navigation systems. The Hopfield model is a physical model used to estimate tropospheric delay corrections, accurately calculating the delay caused by satellite signals propagating in the troposphere. Compared to the Saastamoinen model, the Hopfield model performs better at high latitudes and altitudes. The Hopfield model's calculations are based on detailed physical calculations of parameters such as atmospheric pressure, temperature delay, and humidity delay, estimating tropospheric delay corrections by solving the tropospheric light refraction equation.

[0060] In this embodiment, the Saastamoinen model is specifically used to calculate the tropospheric delay. The formula for the Saastamoinen model is as follows:

[0061] ;

[0062] in, This represents the calculated tropospheric delay. Indicates the current atmospheric pressure. The standard atmospheric pressure is typically taken as 1013.25 hPa. The current temperature. This refers to the sea level temperature, typically taken as 288.15K (15°C). It is the water vapor pressure. The latitude of the navigation receiver. The elevation angle is calculated from the position of the navigation receiver and the position of the satellite. For the delay of the tropospheric dry component, This is a delay in the tropospheric moisture content. This is an elevation mapping function used to map the tropospheric zenith delay to the satellite signal path direction.

[0063] The formula for satellite elevation angle is:

[0064] ;

[0065] in The coordinates of the satellite in the station-centered coordinate system are represented by the eastward, northward, and celestial components, respectively, and are obtained by matrix transformation using the satellite position and receiver position according to classical formulas.

[0066] Specifically, step 2 includes:

[0067] Step 2.1, calculate the tropospheric delay Tro1.

[0068] Using the Saastamoinen model, calculate the first... A satellite in The tropospheric delay at that location is .

[0069] Step 2.2, calculate the tropospheric delay Tro2.

[0070] Using the Saastamoinen model, calculate the first... A satellite in The tropospheric delay at that location is .

[0071] Step 2.3: Calculate the rate of change of tropospheric delay.

[0072] right and Find the difference to get the first... The rate of change of tropospheric delay for each satellite It should be noted that the value within parentheses in the formula for calculating the tropospheric delay rate can be adjusted according to the actual implementation situation. For example: Can be replaced with , Can be replaced with Accordingly, the value of the denominator in the calculation formula needs to be obtained from... Replace with .

[0073] Step 2.4, convert to Doppler frequency shift error.

[0074] Will The first is converted to the tropospheric delay variation caused by the first The Doppler frequency shift error of each satellite is expressed as .

[0075] Step 3, Doppler frequency shift recorrection: The corrected Doppler frequency shift is recorrected based on the Doppler frequency shift error to obtain the recorrected Doppler frequency shift.

[0076] Specifically, the first [unclear] caused by tropospheric delay variation Doppler frequency shift error of each satellite Added in Doppler shift corrected for each satellite Up, get the first The Doppler frequency shift of each satellite after recalibration is expressed as .

[0077] Step 4, Precise velocity calculation: Based on the recalibrated Doppler frequency shift, the velocity is calculated again to obtain the precise velocity information of the navigation receiver.

[0078] Specifically, based on the first Doppler shift of satellite recalibration The speed measurement and calculation were performed again to obtain the accurate speed information of the navigation receiver, which is represented as follows:

[0079] ;

[0080] in, This represents the precise velocity of the navigation receiver in the ECEF coordinate system. for Three-dimensional velocity components in the ECEF coordinate system.

[0081] The satellite navigation velocity measurement method described above, based on tropospheric delay dynamic error correction, differs from existing techniques that "compress integration time" to reduce the impact of tropospheric delay dynamic errors. This method creatively uses the vertical velocity and elevation of the navigation receiver as inputs to a mathematical-physical model to solve for the Doppler shift and precisely subtract the error source itself from its physical origin. This results in more accurate and less biased satellite navigation velocity measurement results both theoretically and practically. Furthermore, since there is no need to compress integration time, this method can fully utilize the high signal-to-noise ratio observations resulting from long integration, effectively suppressing random noise and making the velocity calculation results smoother and more reliable. Additionally, because systematic errors are effectively subtracted and observation noise is low, the sensitivity of the entire velocity calculation process to observation geometry and carrier maneuvers is reduced, resulting in more stable and robust velocity measurement results.

[0082] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0083] In one embodiment, such as Figure 2 As shown, a satellite navigation velocity measurement system based on tropospheric delay dynamic error correction is provided, comprising:

[0084] The standard position and velocity calculation module is used to correct the raw observation information acquired by the navigation receiver, which includes the original Doppler frequency shift, to obtain the corrected observation information. Based on the corrected observation information, least squares calculation and velocity measurement are performed to obtain the elevation of the navigation receiver. and vertical velocity ;

[0085] The Doppler frequency shift error calculation module is used to calculate the Doppler frequency shift error of each satellite using an empirical model of tropospheric delay. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite.

[0086] The Doppler frequency shift recorrection module is used to recorrect the corrected Doppler frequency shift based on the Doppler frequency shift error, and obtain the recorrected Doppler frequency shift.

[0087] The precise velocity calculation module is used to perform velocity calculation again based on the recalibrated Doppler frequency shift to obtain the precise velocity information of the navigation receiver.

[0088] Specific limitations regarding the satellite navigation velocity measurement system based on tropospheric delay dynamic error correction can be found in the limitations of the satellite navigation velocity measurement method based on tropospheric delay dynamic error correction mentioned above, and will not be repeated here. Each module in the aforementioned satellite navigation velocity measurement system based on tropospheric delay dynamic error correction can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independent of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the corresponding operations of each module.

[0089] In one embodiment, a high-speed moving vehicle is also provided, including a navigation receiver mounted on the high-speed moving vehicle; the vertical speed of the high-speed moving vehicle is greater than a preset threshold (e.g., 50 m / s), and the navigation receiver applies the above-mentioned satellite navigation velocity measurement method based on tropospheric delay dynamic error correction to obtain accurate speed information.

[0090] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0091] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application.

Claims

1. A satellite navigation velocity measurement method based on tropospheric delay dynamic error correction, characterized in that, The method includes: The original observation information, which includes the original Doppler frequency shift, acquired by the navigation receiver is corrected to obtain corrected observation information. Based on this corrected information, least squares and velocity calculations are performed to obtain the elevation of the navigation receiver. and vertical velocity The original observation information includes the original pseudorange and the original Doppler frequency shift, and the corrected observation information includes the corrected pseudorange and the corrected Doppler frequency shift. Using the empirical model of tropospheric delay, the delay of each satellite was calculated. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite. The corrected Doppler frequency shift is re-corrected based on the Doppler frequency shift error to obtain the re-corrected Doppler frequency shift. Based on the recalibrated Doppler frequency shift, the velocity is calculated again to obtain the accurate velocity information of the navigation receiver.

2. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 1, characterized in that, The original observation information, which includes the original Doppler frequency shift, acquired by the navigation receiver is corrected to obtain the corrected observation information, including: Using the raw observation information, including the raw pseudorange and raw Doppler shift, obtained from the baseband of the navigation receiver, and the ephemeris information obtained from the raw message, the satellite position, satellite velocity, satellite clock error, and satellite frequency difference are calculated for each satellite. The raw pseudorange is then corrected based on ionospheric delay information and tropospheric delay information to obtain the corrected pseudorange. Finally, the raw Doppler shift is corrected using the satellite frequency difference to obtain the corrected Doppler shift.

3. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 2, characterized in that, The original Doppler frequency shift is corrected using the satellite frequency difference, resulting in the corrected Doppler frequency shift, expressed as: ； in, It is the first Doppler shift corrected for each satellite; It is the first The raw Doppler frequency shift obtained from satellite measurements; It is the satellite frequency offset; This is the nominal frequency of the current satellite signal.

4. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 2, characterized in that, Based on the corrected observation information, least squares calculation and velocity measurement calculation are performed respectively to obtain the elevation of the navigation receiver. and vertical velocity ,include: The position information of the navigation receiver is obtained by performing least-squares calculation using satellite position and corrected pseudorange, and the longitude of the navigation receiver is obtained by performing latitude-longitude-altitude conversion. ,latitude and elevation ; Using the position information of the navigation receiver, satellite velocity, and the corrected Doppler frequency shift, velocity calculation is performed to obtain the initial velocity information of the navigation receiver, expressed as: ； in, This represents the initial velocity of the navigation receiver in the ECEF coordinate system. for Three-dimensional velocity components in the ECEF coordinate system; The speed of light; It is the first Doppler shift corrected for each satellite; This is the nominal frequency of the current satellite signal; To point from the navigation receiver to the first The unit direction vector of a satellite; For the first The velocity of the satellite in ECEF coordinates; By using the initial velocity in the ECEF coordinate system Perform a coordinate transformation to obtain the initial velocity of the navigation receiver in the ENU coordinate system. ; These represent the eastward velocity, the northward velocity, and the upward velocity, respectively, with the upward velocity also known as the vertical velocity.

5. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 1, characterized in that, The empirical model for tropospheric delay is either the Saastamoinen model or the Hopfield model.

6. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 5, characterized in that, Using the empirical model of tropospheric delay, the delay of each satellite was calculated. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite, including: Using the Saastamoinen model, calculate the first... A satellite in and The tropospheric delays at the locations are respectively and ;in, The elevation of the navigation receiver. The vertical velocity of the navigation receiver; right and Find the difference to get the first... The rate of change of tropospheric delay for each satellite And convert it to obtain the first tropospheric delay caused by the change in tropospheric delay. The Doppler frequency shift error of the satellite is ;in, The nominal frequency of the current satellite signal. It is the speed of light.

7. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 6, characterized in that, The corrected Doppler frequency shift is recorrected based on the Doppler frequency shift error to obtain the recorrected Doppler frequency shift, including: The first caused by tropospheric delay variation Doppler frequency shift error of each satellite Added in Doppler shift corrected for each satellite Up, get the first The Doppler frequency shift of each satellite after recalibration is expressed as .

8. The satellite navigation velocity measurement method based on tropospheric delay dynamic error correction according to claim 7, characterized in that, Based on the recorrected Doppler frequency shift, a velocity calculation is performed again to obtain the accurate velocity information of the navigation receiver, including: Based on the Doppler shift of satellite recalibration The speed measurement and calculation were performed again to obtain the accurate speed information of the navigation receiver, which is represented as follows: ； in, This represents the precise velocity of the navigation receiver in the ECEF coordinate system. for Three-dimensional velocity components in the ECEF coordinate system; The speed of light; This is the nominal frequency of the current satellite signal; To point from the navigation receiver to the first The unit direction vector of a satellite; For the first The velocity of the satellite in ECEF coordinates.

9. A satellite navigation velocity measurement system based on tropospheric delay dynamic error correction, characterized in that, The system includes: The conventional position and velocity calculation module is used to correct the raw observation information acquired by the navigation receiver, which includes the original Doppler frequency shift, to obtain corrected observation information. Based on the corrected observation information, least squares calculation and velocity calculation are performed to obtain the elevation of the navigation receiver. and vertical velocity The original observation information includes the original pseudorange and the original Doppler frequency shift, and the corrected observation information includes the corrected pseudorange and the corrected Doppler frequency shift. The Doppler frequency shift error calculation module is used to calculate the Doppler frequency shift error of each satellite using an empirical model of tropospheric delay. and The tropospheric delay at the location is calculated, and after obtaining the rate of change of tropospheric delay for each satellite by subtraction, the Doppler frequency shift error caused by the change of tropospheric delay is calculated for each satellite. The Doppler frequency shift recorrection module is used to recorrect the corrected Doppler frequency shift based on the Doppler frequency shift error to obtain the recorrected Doppler frequency shift. The precise velocity calculation module is used to perform velocity calculation again based on the recorrected Doppler frequency shift to obtain the precise velocity information of the navigation receiver.

10. A high-speed motion carrier, characterized in that, The system includes a navigation receiver mounted on the high-speed moving vehicle; the vertical speed of the high-speed moving vehicle is greater than a preset threshold, and the navigation receiver uses the satellite navigation velocity measurement method based on tropospheric delay dynamic error correction as described in any one of claims 1-8 to obtain accurate velocity information.

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