Pseudo-satellite dimensionality reduction positioning method, system and related components under occlusion scenarios

Abstract

The present invention discloses a method, system and related components for positioning a pseudolite in a reduced dimension under an occlusion scenario. The method includes: obtaining the three-dimensional coordinates of the pseudolite in a reference rectangular coordinate system under the occlusion scenario; fixing one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with map matching according to the linear movement trajectory of the receiver, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction under the occlusion scenario; based on the three-dimensional coordinates of the pseudolite and the z-axis coordinate and one of the horizontal axis coordinates of the receiver, the target horizontal axis coordinate of the receiver is solved by using the least squares algorithm. The present invention obtains positioning initial information through map matching to identify the positioning range, and then reduces the dimension of the positioning state quantity by reducing the number of coordinates to be solved, thereby improving the positioning accuracy and reliability.

Description

Technical Field

[0001] The present invention relates to the field of pseudolite technology, and in particular to a pseudolite dimensionality reduction positioning method, system and related components in an occlusion scenario. Background Art

[0002] At present, the development of global navigation satellite systems (GNSS) has been relatively mature, including four major global navigation satellite systems such as GPS, GLONASS, Beidou, and Galileo, and regional navigation systems such as QZSS and IRNSS. The above systems can meet the positioning, navigation, and timing requirements in most outdoor scenarios. However, the satellites of the GNSS system have high orbits and aim to provide wide-area services as the basic goal. The signal strength reaching the user is low, resulting in that the navigation signal is easily blocked, especially in areas such as urban canyons, indoors, underground, tunnels, underwater, etc. The satellite navigation signal is completely blocked and cannot provide navigation services. Pseudolite technology is an effective method to solve the positioning problem in various satellite navigation signal occlusion scenarios such as indoors, underground, tunnels, underwater, etc. The pseudolite system adopts the same technical principle as the satellite navigation system, arranges several navigation signal transmitting devices in the above scenarios, and transmits radio signals with the same signal system as the real navigation satellite signal to cover the area without satellite navigation signals. The terminal completes distance measurement by receiving the signals transmitted by the pseudolite nodes, and then realizes high-precision positioning. Pseudolite technology can support various ordinary GNSS terminals such as mobile phones and vehicles to directly complete positioning in the satellite navigation signal occlusion scenario without hardware upgrade, and the required system upgrade cost is relatively low.

[0003] However, generally, the environments of various satellite navigation signal occlusion scenarios such as indoors, underground, tunnels, underwater, etc. are complex, and the multipath effect is very serious. The multipath error of L1 pseudocode ranging may reach the order of 10 m, and the multipath error of L5 pseudocode ranging will also reach the order of meters. Even if the method of carrier-smoothed pseudorange is adopted, the multipath error is also in the order of meters. Relative to the distance range of several meters to dozens of meters between the receiver and the pseudolite in the indoor pseudolite positioning scenario, the multipath error is even greater than the actual pseudorange value, which will lead to a serious decline in the indoor positioning accuracy based on pseudolites, and even cause the positioning solution equation to be singular when the positioning initial value is configured unreasonably. Summary of the Invention

[0004] The embodiments of the present invention provide a pseudolite dimensionality reduction positioning method, system and related components in an occlusion scenario, aiming to solve the problem of low pseudolite positioning accuracy in the existing technology in the occlusion scenario.

[0005] In a first aspect, the embodiments of the present invention provide a pseudolite dimensionality reduction positioning method in an occlusion scenario, including:

[0006] Obtain the three-dimensional coordinates of the pseudolite in a reference rectangular coordinate system in the occlusion scenario;

[0007] According to the linear movement trajectory of the receiver, fix one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with the map matching method, and determine the z-axis coordinate of the receiver in the reference rectangular coordinate system according to the prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction in the occlusion scenario.

[0008] Based on the three-dimensional coordinates of the pseudolites, the z-axis coordinate and one of the horizontal axis coordinates of the receiver, use the least squares algorithm to solve the target horizontal axis coordinate of the receiver.

[0009] In a second aspect, an embodiment of the present invention provides a pseudolite dimensionality reduction positioning system in an occlusion scenario, which includes:

[0010] A three-dimensional coordinate acquisition unit for acquiring the three-dimensional coordinates of the pseudolites in the reference rectangular coordinate system in the occlusion scenario;

[0011] An axis coordinate determination unit for fixing one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system according to the linear movement trajectory of the receiver in combination with the map matching method, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to the prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction in the occlusion scenario.

[0012] A target horizontal axis coordinate calculation unit for solving the target horizontal axis coordinate of the receiver based on the three-dimensional coordinates of the pseudolites, the z-axis coordinate and one of the horizontal axis coordinates of the receiver by using the least squares algorithm.

[0013] In a third aspect, an embodiment of the present invention further provides a computer device, which includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the pseudolite dimensionality reduction positioning method in the occlusion scenario described in the first aspect above.

[0014] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor is caused to execute the pseudolite dimensionality reduction positioning method in the occlusion scenario described in the first aspect above.

[0015] The embodiments of the present invention provide a method and system for pseudo-satellite dimensionality reduction positioning in an occlusion scenario and related components. The method includes: obtaining the three-dimensional coordinates of pseudo-satellites in a reference rectangular coordinate system in an occlusion scenario; fixing one of the horizontal axis coordinates of a receiver in the reference rectangular coordinate system in combination with a map matching method according to the linear movement trajectory of the receiver, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudo-satellites are arranged along the target horizontal axis direction in the occlusion scenario; based on the three-dimensional coordinates of the pseudo-satellites and the z-axis coordinate and one of the horizontal axis coordinates of the receiver, the target horizontal axis coordinate of the receiver is calculated by using the least squares algorithm. The embodiments of the present invention identify the positioning range by obtaining the initial positioning information through map matching, and then reduce the dimensionality of the positioning state quantity by reducing the number of coordinates to be solved, thereby improving the positioning accuracy and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic flowchart of the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario provided by the embodiments of the present invention;

[0018] Figure 2 It is an X-axis DOP schematic diagram of the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario provided by the embodiments of the present invention;

[0019] Figure 3 It is a Y-axis DOP schematic diagram of the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario provided by the embodiments of the present invention;

[0020] Figure 4 It is a Z-axis DOP schematic diagram of the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario provided by the embodiments of the present invention;

[0021] Figure 5 It is a schematic block diagram of the pseudo-satellite dimensionality reduction positioning system in an occlusion scenario provided by the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0023] It should be understood that, as used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or their groups.

[0024] It should also be understood that the terms used in this specification of the present invention are merely for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0025] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0026] Please refer to Figure 1 , Figure 1 , which is a schematic flow chart of a method for pseudo-satellite dimensionality reduction positioning in an occlusion scenario provided by an embodiment of the present invention. The method includes steps S101 to S103.

[0027] S101. Obtain the three-dimensional coordinates of the pseudo-satellite in the reference rectangular coordinate system in the occlusion scenario;

[0028] S102. Fix one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with the map matching method according to the linear movement trajectory of the receiver, and determine the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudo-satellites are arranged along the target horizontal axis direction in the occlusion scenario;

[0029] S103. Based on the three-dimensional coordinates of the pseudo-satellite and the z-axis coordinate and one of the horizontal axis coordinates of the receiver, use the least squares algorithm to solve the target horizontal axis coordinate of the receiver.

[0030] In this embodiment, first obtain the three-dimensional coordinates of the pseudo-satellite in the reference rectangular coordinate system, then obtain one of the horizontal axis coordinates of the receiver through the linear movement trajectory where the map matching is located, then determine the z-axis coordinate of the receiver according to prior information, and finally, according to the obtained three-dimensional coordinates of the pseudo-satellite and one of the horizontal axis coordinates and the z-axis coordinate of the receiver, solve the target horizontal axis coordinate of the receiver.

[0031] Under normal circumstances, the state quantity to be estimated for positioning and solving is the coordinate [x u y u z u, if three coordinates are solved simultaneously, the number of observables required is at least 4, and the measurement error should also be much smaller than the actual geometric distance. In occluded scenarios such as underground garages, indoors, and tunnels, the distance between vehicles and various handheld terminals from the ground is usually on the order of 1m to 2m. For example, the height of a vehicle from the ground is generally about 1.5m, and the height of an adult holding a mobile phone is about 1.2m. Therefore, first, in the above occluded scenarios, three-dimensional positioning can be reduced to two-dimensional positioning. Set the z u coordinate as a known quantity, and only estimate the [x u y u two-dimensional coordinates for each positioning. On the other hand, in a tunnel scenario, if lane-level positioning is not performed, only the position of the vehicle in the tunnel direction needs to be solved. In scenarios such as underground garages, vehicles can only move along the lanes in the garage. In indoor scenarios, the range where various handheld terminals can move is generally also within a certain linear range. Therefore, in the above various occluded scenarios, the running straight line where the receiver is located can be identified through map matching, so that two-dimensional positioning can be further simplified to only solve the x u or y u one-dimensional coordinate. By introducing prior information such as map matching, indoor three-dimensional positioning in an occluded scenario can finally be reduced to only solving the x u or y u one-dimensional positioning, which can greatly reduce the number of pseudolite deployments in the occluded environment and also improve the positioning success rate. In this embodiment, after obtaining the three-dimensional coordinates of the pseudolites in the reference rectangular coordinate system in the occluded scenario , first determine the z u coordinate of the receiver, and determine the x u coordinate (or y u coordinate) of the receiver according to the linear movement trajectory of the receiver and the map matching information. Finally, use the least squares algorithm to solve the y u coordinate (or x u coordinate) of the receiver.

[0032] In one embodiment, before obtaining the three-dimensional coordinates of the pseudolites in the reference rectangular coordinate system in the occluded scenario, it includes:

[0033] The receiver queries the map matching information database through the Internet system to obtain the available pseudolite numbers in the current occluded scenario and obtains the measurement data of the corresponding pseudolite numbers.

[0034] In this embodiment, when deploying pseudolites in an occlusion scenario, the number of each pseudolite is pre-recorded, and then the numbers of each pseudolite are uploaded to the Internet system for registration. When the receiver enters the occlusion scenario, the numbers of the pseudolites in the current occlusion scenario are queried through the Internet system, and the measurement data of the corresponding pseudolites are obtained according to the queried numbers. The receiver measures the pseudolites to obtain the corresponding measurement data, and saves the measurement data locally for query.

[0035] In one embodiment, the heights of the multiple pseudolites are within the same range. In this embodiment, during the deployment process of the pseudolites, in order to make the data more accurate, the heights of the pseudolites are set within the same range to reduce measurement errors.

[0036] The dilution of precision (DOP) quantitatively characterizes the amplification effect of the pseudolite layout on the measurement noise. In the traditional three-dimensional GNSS positioning solution process, in order to improve the positioning accuracy as much as possible under the same measurement accuracy, the DOP value is reduced as much as possible through orbit parameter optimization. In the one-dimensional positioning process of this embodiment, taking the solved target horizontal axis coordinate as x u coordinate as an example, then y u , z u The typical values are obtained through map matching and introduced into the observation equation as fixed coordinates. However, in fact, only the lane where the receiver is located or the linear motion range can be determined through the map matching information, and y u cannot be accurately known. For example, after knowing the lane where the receiver is located, if the lane center line coordinate is taken as y u , then the error of y u will be > 2m. Similarly, z u cannot be accurately measured either. Different vehicle heights, different installation or placement positions of vehicle receivers, and different heights of pedestrian-held receivers will all introduce errors in z u . The DOP value quantitatively characterizes the influence of measurement errors on the positioning result. Under the same measurement error, the smaller the DOP value, the higher the positioning accuracy; on the other hand, the DOP value also quantitatively characterizes the contribution of position errors to the measurement residuals. Under the same position error, the larger the DOP value, the smaller the measurement residuals caused. Based on the above basic principles, in order to reduce the influence of the errors of the y u , z u fixed coordinates on the measurement residuals, it is necessary to ensure that the DOP in the y u , z u directions is as large as possible, while the DOP in the x u direction is as small as possible. To achieve the above goal, during the one-dimensional positioning process, the pseudolites are arranged along the linear direction to be located, that is, along x uDirection layout, and try to ensure that all the pseudolites have the same height. For example, in a tunnel, arrange them in a line along the tunnel top, and in an underground garage, arrange them in a line along the garage top of the garage lane.

[0037] For a certain linear layout scheme, its DOP is as Figures 2 - 4 shown. It can be seen that in a one-dimensional layout, the DOP value in the X direction is smaller, significantly smaller than the DOP values in the Y and Z directions, which can ensure a higher positioning accuracy in the X direction. At the same time, the fixed coordinate errors in the Y and Z directions have less impact on the positioning result.

[0038] In an embodiment, after calculating the other horizontal coordinate of the receiver by using the least squares algorithm based on the three-dimensional coordinates of the pseudolite, the z-axis coordinate of the receiver, and one of its horizontal coordinates, it includes:

[0039] Obtain the horizontal axis coordinate of the intersection point of the current lane in the occlusion scenario, and determine whether the absolute value of the error between the horizontal axis coordinate of the intersection point target and the calculated current target horizontal axis coordinate is less than a preset threshold;

[0040] If it is less than the preset threshold, it is determined that the receiver is within the intersection range, and the least squares algorithm is used to simultaneously calculate one of the horizontal axis coordinates of the receiver and the target horizontal axis coordinate.

[0041] In this embodiment, the horizontal axis coordinate of the intersection point of the current lane is judged by the map matching method, the absolute value of the error between the horizontal axis coordinate of the intersection point target and the calculated current target horizontal axis coordinate is calculated, and it is judged whether the absolute value of the error is less than the preset threshold; if it is less than the preset threshold, it is determined that the receiver is within the intersection range, and one of the horizontal axis coordinates of the receiver and the target horizontal axis coordinate are simultaneously calculated.

[0042] In this embodiment, the lane where the receiver is located is first determined, and then one of the horizontal axis coordinates is fixed to complete the one-dimensional positioning calculation of the target horizontal axis coordinate. However, when the receiver is at the intersection of two lanes, the positioning coordinate axes may change, and at this time, it is impossible to determine whether to fix the Y-axis or X-axis coordinate for calculation. If the coordinate axis is fixed incorrectly, it will directly lead to incorrect positioning calculation coordinates or even no solution for the positioning algorithm. Therefore, it is necessary to judge the current position of the receiver. If the absolute value of the error between the horizontal axis coordinate of the intersection point target and the calculated current target horizontal axis coordinate is less than the preset threshold, it is determined that it is within the intersection range, and one of the horizontal axis coordinates and the target horizontal axis coordinate need to be simultaneously calculated.

[0043] In an embodiment, the using the least squares algorithm to simultaneously calculate one of the horizontal axis coordinates of the receiver and the target horizontal axis coordinate includes:

[0044] Obtain the first positioning observation residual and the second positioning observation residual of the solution processes of one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver respectively;

[0045] Calculate the RMS values corresponding to the first positioning observation residual and the second positioning observation residual respectively;

[0046] Compare the magnitudes between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual;

[0047] If the absolute value of the difference between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual is greater than the difference threshold within a specified time period, then take the axis corresponding to the positioning observation residual with the smaller RMS value as the target axis.

[0048] In this embodiment, when it is calculated that the receiver is within the intersection point range, calculate one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver simultaneously, and obtain the first positioning observation residual and the second positioning observation residual during the solution process; calculate the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual, and compare the magnitudes between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual; if the absolute value of the difference between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual is greater than the difference threshold within a specified time period, then take the axis corresponding to the positioning observation residual with the smaller RMS value as the target axis.

[0049] Specifically, calculate the X-axis coordinate and the Y-axis coordinate simultaneously, and track the positioning observation residuals corresponding to the two horizontal axis coordinates in real time, and statistically calculate the RMS values of the observation residuals of the positioning results independently solved every second; if within 5 s, the RMS value of the positioning solution observation residual in a certain dimension is significantly smaller than the RMS value of the positioning solution observation residual in the other dimension, then take the axis corresponding to the smaller RMS value of the observation residual as the target axis.

[0050] In one embodiment, the method for solving the target horizontal axis coordinate of the receiver by using the least squares algorithm includes:

[0051] Calculate the pseudorange ρ of the jth pseudolite by using the following formula j :

[0052]

[0053] where, [x j y j z j is the pseudolite coordinate; y u is the y-axis coordinate of the receiver; z u is the z-axis coordinate of the receiver; x uFor the x-axis coordinate t to be received u is the clock bias to be estimated by the receiver;

[0054] Perform Taylor expansion on the pseudorange ρ through the total differential formula j (1) and retain the first-order term:

[0055]

[0056] wherein, are the estimated values of x and t for this iteration respectively u 、t u ;

[0057] Solve the target horizontal axis coordinate of the receiver according to the following formula:

[0058]

[0059] wherein,

[0060] In this embodiment, first calculate the pseudorange ρ of the j-th pseudolite j , then perform Taylor expansion on the pseudorange ρ through the total differential formula j (1) and retain the first-order term, and finally use to solve the target horizontal axis coordinate of the receiver.

[0061] According to the total differential formula, perform Taylor expansion on the above pseudorange ρ j (1) and retain the first-order term:

[0062]

[0063] wherein: are the estimated values of x and t for this iteration respectively u 、t u ;

[0064] Take:

[0065]

[0066] Then: Finally, by the least squares algorithm: The target horizontal axis coordinate of the receiver can be solved by iteratively executing the above formula.

[0067] Please refer to Figure 5 , Figure 5 is a schematic block diagram of a pseudolite dimensionality reduction positioning system in an occlusion scenario provided by an embodiment of the present invention. The pseudolite dimensionality reduction positioning system 200 in the occlusion scenario includes:

[0068] A three-dimensional coordinate acquisition unit 201 for acquiring the three-dimensional coordinates of a pseudolite in a reference rectangular coordinate system in an occluded scenario;

[0069] An axis coordinate determination unit 202 for fixing one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with map matching according to the linear movement trajectory of the receiver, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction in the occluded scenario;

[0070] A target horizontal axis coordinate calculation unit 203 for calculating the target horizontal axis coordinate of the receiver by using the least squares algorithm based on the three-dimensional coordinates of the pseudolite and the z-axis coordinate and one of the horizontal axis coordinates of the receiver.

[0071] In one embodiment, the three-dimensional coordinate acquisition unit 201 includes:

[0072] A pseudolite measurement data acquisition unit for the receiver to query the map matching information database through the Internet system to obtain the available pseudolite numbers in the current occluded scenario and acquire the measurement data of the corresponding pseudolite numbers.

[0073] In one embodiment, a pseudolite height setting unit for the heights of the plurality of pseudolites to be within the same range.

[0074] In one embodiment, the target horizontal axis coordinate calculation unit 203 includes:

[0075] An error comparison unit for acquiring the target horizontal axis coordinate of the intersection of the current lane in the occluded scenario and determining whether the absolute value of the error between the target horizontal axis coordinate of the intersection and the calculated current target horizontal axis coordinate is less than a preset threshold;

[0076] A two-way horizontal axis coordinate calculation unit for determining that the receiver is within the intersection range if it is less than the preset threshold and simultaneously calculating one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver by using the least squares algorithm.

[0077] In one embodiment, the two-way horizontal axis coordinate calculation unit includes:

[0078] A positioning observation residual acquisition unit for respectively acquiring a first positioning observation residual and a second positioning observation residual in the calculation processes of one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver;

[0079] A positioning observation residual RMS value calculation unit for calculating the RMS values corresponding to the first positioning observation residual and the second positioning observation residual respectively;

[0080] A positioning observation residual RMS value comparison unit for comparing the magnitude of the RMS value of the first positioning observation residual with the RMS value of the second positioning observation residual;

[0081] A difference threshold comparison unit for, if the absolute value of the difference between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual is greater than the difference threshold within a specified time period, taking the axis corresponding to the positioning observation residual with the smaller RMS value as the target axis.

[0082] In one embodiment, the solution of the target horizontal axis coordinates of the receiver using the least squares algorithm includes:

[0083] A pseudorange calculation unit for calculating the pseudorange ρ of the j-th pseudolite using the following formula j :

[0084]

[0085] wherein, [x j y j z j is the pseudolite coordinate; y u is the y-axis coordinate of the receiver; z u is the z-axis coordinate of the receiver; x u is the x-axis coordinate to be received, t u is the clock bias to be estimated of the receiver;

[0086] A pseudorange formula Taylor expansion unit for performing Taylor expansion on the pseudorange ρ j (1) through the total differential formula and retaining the first-order term:

[0087]

[0088] wherein, are the estimated values of x u , t u in this iteration respectively;

[0089] A least squares algorithm solution unit for solving the target horizontal axis coordinates of the receiver according to the following formula:

[0090]

[0091] wherein,

[0092] An embodiment of the present invention further provides a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the pseudo-satellite dimensionality reduction positioning method in the occlusion scenario as described above is implemented.

[0093] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the pseudo-satellite dimensionality reduction positioning method in the occlusion scenario as described above is implemented.

[0094] The various embodiments in the specification are described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple. For the relevant parts, refer to the description in the method section. It should be noted that for those of ordinary skill in the art in the technical field of the present invention, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0095] It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

Claims

1. A pseudo-satellite dimensionality reduction positioning method in an occlusion scenario, characterized in that Including: Obtaining the three-dimensional coordinates of pseudolites in a reference rectangular coordinate system under an occlusion scenario; According to the linear movement trajectory of the receiver, fixing one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with the map matching method, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction under the occlusion scenario; Based on the three-dimensional coordinates of the pseudolites, the z-axis coordinate of the receiver, and one of the horizontal axis coordinates, using the least squares algorithm to solve the target horizontal axis coordinate of the receiver; After using the least squares algorithm to solve the target horizontal axis coordinate of the receiver based on the three-dimensional coordinates of the pseudolites, the z-axis coordinate of the receiver, and one of the horizontal axis coordinates, including: Obtaining the target horizontal axis coordinate of the intersection point of the current lane under the occlusion scenario, and determining whether the absolute value of the error between the target horizontal axis coordinate of the intersection point and the calculated current target horizontal axis coordinate is less than a preset threshold; If it is less than the preset threshold, it is determined that the receiver is within the intersection range, and the least squares algorithm is used to simultaneously solve one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver.

2. The pseudo-satellite dimensionality reduction positioning method in an occluded scenario according to claim 1, wherein, Before obtaining the three-dimensional coordinates of the pseudolites in the reference rectangular coordinate system under the occlusion scenario, including: The receiver queries the map matching information database through the Internet system to obtain the available pseudolite numbers under the current occlusion scenario, and obtains the measurement data corresponding to the corresponding pseudolite numbers.

3. The pseudo-satellite dimensionality reduction positioning method in an occluded scenario according to claim 1, wherein, The heights of the plurality of pseudolites are within the same range.

4. The method for pseudo-satellite dimensionality reduction positioning in an occluded scenario according to claim 1, wherein The using the least squares algorithm to simultaneously solve one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver includes: Respectively obtaining the first positioning observation residual and the second positioning observation residual in the solution process of one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver; Calculating the RMS values corresponding to the first positioning observation residual and the second positioning observation residual respectively; Comparing the magnitudes of the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual; If the absolute value of the difference between the RMS value of the first positioning observation residual and the RMS value of the second positioning observation residual is greater than the difference threshold within a specified time period, the axis corresponding to the positioning observation residual with the smaller RMS value is used as the target axis.

5. The pseudo-satellite dimensionality reduction positioning method in an occluded scenario according to claim 1, characterized in that, The using the least squares algorithm to solve the target horizontal axis coordinate of the receiver includes: Calculate the pseudorange ρ of the j-th pseudolite using the following formula j :[[]]END]] Among them, is the pseudolite coordinate; y u is the y-axis coordinate of the receiver; z u is the z-axis coordinate of the receiver; x u is the x-axis coordinate of the receiver, and t u is the clock bias to be estimated of the receiver; Perform Taylor expansion on the pseudorange ρ through the total differential formula j and retain the first-order term: Among them, are the estimated values of x u and t u for this iteration respectively; Solving the target horizontal axis coordinate of the receiver according to the following formula: Among them, 6. A pseudo-satellite dimensionality reduction positioning system in an occlusion scenario, characterized in that, Including: A three-dimensional coordinate acquisition unit for obtaining the three-dimensional coordinates of pseudolites in a reference rectangular coordinate system under an occlusion scenario; An axis coordinate determination unit for fixing one of the horizontal axis coordinates of the receiver in the reference rectangular coordinate system in combination with the map matching method according to the linear movement trajectory of the receiver, and determining the z-axis coordinate of the receiver in the reference rectangular coordinate system according to prior information; wherein, a plurality of pseudolites are arranged along the target horizontal axis direction under the occlusion scenario; A target horizontal axis coordinate solution unit for using the least squares algorithm to solve the target horizontal axis coordinate of the receiver based on the three-dimensional coordinates of the pseudolites, the z-axis coordinate of the receiver, and one of the horizontal axis coordinates; After the target horizontal axis coordinate calculation unit, it includes: An error comparison unit, configured to obtain the intersection target horizontal axis coordinate of the current lane in an occlusion scenario, and determine whether the absolute value of the error between the intersection target horizontal axis coordinate and the calculated current target horizontal axis coordinate is less than a preset threshold; A two-way horizontal axis coordinate calculation unit, configured to determine that the receiver is within the intersection range if it is less than the preset threshold, and use the least squares algorithm to simultaneously calculate one of the horizontal axis coordinates and the target horizontal axis coordinate of the receiver.

7. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the processor is caused to execute the pseudo-satellite dimensionality reduction positioning method in an occlusion scenario as described in any one of claims 1 to 5.

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