An indoor positioning system

Abstract

The present application discloses an indoor positioning system, which includes: a plurality of pseudo-satellites, any of which can broadcast at least two signals with different frequencies; a virtual grid construction unit, which divides the garage space into virtual grid segments and sets the anchor points of each virtual grid segment, records the position information of the anchor points to establish a virtual grid anchor point position feature library; an anchor point position feature spectrum construction unit, which constructs an anchor point position feature spectrum corresponding to any anchor point; wherein the anchor point position feature spectrum is used to deduce the first signal feature parameter information of all virtual points in the search space, and construct a first signal feature parameter information library, the search space is centered on the first anchor point, in response to the second feature parameter information of the mobile terminal receiving the signal matching the first signal feature parameter information, based on the position information of the first anchor point and the virtual point matching the search space, the position of the mobile terminal is obtained. The present application can provide accurate positioning services for mobile terminals indoors.

Description

Technical Field

[0001] The present application relates to the field of spatial positioning, and in particular to an indoor positioning system. Background Art

[0002] In complex buildings such as shopping malls, hospitals, and parking lots, traditional GPS positioning is affected by the obstruction of buildings, and the positioning signal is subject to many interferences when entering the indoor environment, resulting in many deficiencies in existing indoor positioning technology. The complexity of the indoor environment has a huge impact on positioning accuracy, and the indoor structures and layouts of different buildings are diverse, and there are small areas in space, requiring positioning technology to have high precision to meet the positioning needs of the specific location of the specific floor of the moving object. However, the existing technology is still insufficient in this regard, especially in the face of extremely high requirements for indoor positioning accuracy, such as positioning navigation in parking lots and positioning management of warehousing and logistics, which is difficult to achieve the ideal level. Summary of the invention

[0003] In order to solve the deficiencies of the prior art, this application adopts the following technical solutions:

[0004] An indoor positioning system, applied to a GNSS micro base station, characterized in that the system comprises:

[0005] A plurality of pseudo-satellites 11, any of which broadcasts at least two signals with different frequencies;

[0006] The virtual grid construction unit 12 is used to divide the garage space into virtual grid segments, set the anchor points of each virtual grid segment, and record the position information of the anchor points to establish a virtual grid anchor point position feature library;

[0007] An anchor point position characteristic spectrum construction unit 13, used to construct an anchor point position characteristic spectrum of a corresponding anchor point for any anchor point;

[0008] Among them, the anchor point position characteristic spectrum is used to deduce the first signal characteristic parameter information at all virtual points in the search space to construct a first signal characteristic parameter information library. The search space is centered on the first anchor point, and in response to the second characteristic parameter information of the signal received by the mobile terminal matching the first signal characteristic parameter information, the position of the mobile terminal is obtained based on the position information of the first anchor point and the matching virtual points in the search space.

[0009] In summary, the purpose of this application is to provide an indoor positioning system, which is applied to GNSS micro base stations. Without changing the satellite system, the pseudo-satellite sends a local simulated GNSS signal to the mobile terminal, marks the indoor space with anchor points, records the signal characteristics of any anchor point position, and constructs a first signal characteristic parameter information library, which provides a data basis for subsequent mobile terminals to receive signals for matching and positioning, and lays the foundation for providing users with accurate positioning services in indoor environments.

[0010] Furthermore, the anchor point position characteristic spectrum is expressed by the following formula:

[0011] ;

[0012] In the formula, , , Indicates the carrier, Doppler, and carrier-to-noise ratio values ​​of the mth pseudo-satellite signal received at the anchor point.

[0013] Furthermore, the corresponding parameters of the anchor point position characteristic spectrum are obtained by WKNN weighted cumulative summation, and the corresponding parameters of the anchor point position characteristic spectrum are expressed by the following formula:

[0014] ;

[0015] In the formula, , , are the carrier phase, Doppler and carrier-to-noise ratio data sets collected at the anchor point positions, d i is the difference with the mean as the center point, k is the amount of data collected in 10 minutes, is the amount of random noise, is the weight coefficient.

[0016] Furthermore, the anchor point setting positions include at least the following positions: garage entrance, garage exit, entrance corner, lane intersection, and lane ten-meter dividing point.

[0017] In a second aspect, the present application provides an indoor positioning system, which is applied to a mobile terminal and is characterized in that the system includes:

[0018] A signal acquisition unit 21 is used to receive signals broadcast by pseudo-satellites, where any pseudo-satellite broadcasts at least two signals with different frequencies;

[0019] The epoch position acquisition unit 22 is used to acquire the position of the first anchor point that is closest to the mobile terminal in the previous positioning cycle, and take the first anchor point as the optimal anchor point;

[0020] A search space construction unit 23, used to set the search space with the optimal anchor point as the center;

[0021] The feature parameter deduction unit 24 is configured to deduce the first signal feature parameter information at all virtual points in the search space to construct a first signal feature parameter information library, and the search space is centered on the optimal anchor point;

[0022] The signal analysis unit 25 is configured to analyze the pseudolite signal received by the signal acquisition unit 21 to obtain the second feature parameter information;

[0023] The positioning unit 26 is configured to match the second feature parameter information with the first signal feature parameter information library. In response to a successful match, based on the position information of the optimal anchor point and the matching virtual point in the search space, obtain the position of the mobile terminal.

[0024] In summary, the purpose of this application is to provide an indoor positioning system applied to a mobile terminal. Without changing the satellite signal system, by analyzing the locally simulated GNSS signal sent by the pseudolite, obtain the signal feature information of the signal received by the mobile terminal, and match the signal feature information of the signal received by the mobile terminal with the signal feature information at all virtual points in the search space, obtain the point in the search space with the highest similarity to the signal feature information of the signal received by the mobile terminal, and combine the point with the highest similarity of the above signal feature information and the center point (i.e., the first anchor point) of the search space to obtain the current position information of the mobile terminal, so as to provide high-precision positioning services for users in the indoor environment.

[0025] Further, the positioning unit 26 uses the particle swarm optimization position estimation algorithm to complete position acquisition according to the second feature parameter information and the first signal feature parameter information library.

[0026] Further, the range of the search space is positively correlated with the positioning period of the system.

[0027] Further, the positioning frequency of the system is 5 Hz.

[0028] Further, the system further includes: a mode setting unit 27. The mode setting unit 27 is configured to set a first mode. In the first mode, the horizontal movement speed of the mobile terminal is less than or equal to 2.8 m / s, and, the horizontal dimension search radius of the search space is 0 m < R ≤ 0.56 m, and the vertical dimension search radius is 0.6 m ≤ H ≤ 1.6 m;

[0029] Further, the mode setting unit 27 is further configured to set a second mode. In the second mode, the horizontal movement speed of the mobile terminal is greater than 2.8 m / s and less than or equal to 10 m / s, and, in the second mode, the horizontal dimension search radius of the search space is 0 m < R ≤ 2 m, and the vertical dimension search radius is 0.4 m ≤ H ≤ 0.6 m, or, the vertical dimension search radius is 0.8 m ≤ H ≤ 1.2 m. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of an indoor positioning system applied to a GNSS micro base station provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of signal characteristics in an indoor positioning system provided in an embodiment of the present application;

[0032] Figure 3 A partial structural diagram of an indoor positioning system applied to a mobile terminal provided in an embodiment of the present application;

[0033] Figure 4 A schematic diagram of the interaction between a mobile terminal and a pseudo-satellite in an indoor positioning system provided by an embodiment of the present application;

[0034] Figure 5 Another partial structural diagram of an indoor positioning system provided in an embodiment of the present application applied to a mobile terminal. DETAILED DESCRIPTION

[0035] The present application will be described in detail below in conjunction with the specific implementation modes shown in the accompanying drawings, but these implementation modes do not limit the present application. Structural, methodological, or functional changes made by ordinary technicians in the field based on these implementation modes are included in the protection scope of the present application.

[0036] In order to address the deficiencies in the prior art, the purpose of the present application is to provide an indoor positioning system, which is applied to a GNSS micro base station. Without changing the satellite system, a pseudo-satellite sends a local simulated GNSS signal to a mobile terminal, marks the indoor space with anchor points, records the signal characteristics of any anchor point position, and constructs a first signal characteristic parameter information library, which provides a data basis for subsequent mobile terminals to receive signals for matching and positioning, and lays the foundation for providing users with accurate positioning services in indoor environments.

[0037] First, as Figure 1 As shown, the present application provides an indoor positioning system, which is applied to a GNSS micro base station, and the system includes:

[0038] A plurality of pseudo-satellites 11, any of which broadcasts at least two signals with different frequencies;

[0039] The virtual grid construction unit 12 is used to divide the garage space into virtual grid segments, set the anchor points of each virtual grid segment, and record the position information of the anchor points to establish a virtual grid anchor point position feature library;

[0040] An anchor point position characteristic spectrum construction unit 13, used to construct an anchor point position characteristic spectrum of a corresponding anchor point for any anchor point;

[0041] Among them, the anchor point position characteristic spectrum is used to deduce the first signal characteristic parameter information at all virtual points in the search space to construct a first signal characteristic parameter information library. The search space is centered on the first anchor point, and in response to the second characteristic parameter information of the signal received by the mobile terminal matching the first signal characteristic parameter information, the position of the mobile terminal is obtained based on the position information of the first anchor point and the matching virtual points in the search space.

[0042] As an optional implementation, the anchor point setting positions include at least the following positions: garage entrance, garage exit, entrance corner, lane intersection, and lane ten-meter dividing point.

[0043] Specifically, in the indoor positioning system of the embodiment of the present application, according to the current ephemeris and the deployment position of the GNSS micro base station, the pseudo-satellite locally simulates the GNSS signal, and then the pseudo-satellite broadcasts at least two signals of different frequencies to the garage space. Furthermore, there is a phase difference quantization change interval between the signals of different frequencies broadcast by the same pseudo-satellite. Based on the phase difference quantization change interval characteristics of the signals of different frequencies, the indoor space can be segmented according to the above characteristics in the subsequent system operation; and there is also a fixed point phase difference characteristic between the signals of the same frequency broadcast by different pseudo-satellites. The fixed phase difference characteristic of the same frequency signals broadcast by different pseudo-satellites at fixed points provides a basis for the subsequent system to construct the anchor position characteristic spectrum.

[0044] The virtual grid construction unit 12 divides the garage or indoor space into virtual grid segments, sets key anchor points in each virtual grid, records the location information of the anchor points, and constructs a virtual grid anchor point location feature library, thereby providing a refined management framework for indoor positioning.

[0045] For example, the above virtual grid anchor point location feature library can be expressed as the following expression:

[0046] ;

[0047] The virtual grid anchor point identifier is set as AP, n is the number of anchor points, ap is the anchor point identifier, and each anchor point feature includes an X-axis coordinate, a Y-axis coordinate, and a Z-axis coordinate, which respectively represent the horizontal position, vertical position, and vertical height of the anchor point in space.

[0048] The construction of the virtual grid divides the indoor space into multiple virtual areas according to preset rules, and each area is provided with one or more anchor points. As an optional implementation method, the setting positions of the anchor points include at least the garage entrance, garage exit, entrance corner, lane intersection, and the lane ten-meter division point. In actual applications, the setting of anchor points in the area can be increased according to different indoor environments. The virtual grid construction unit 12 refines the large-scale indoor space into manageable units, and combined with the anchor point position feature library, it helps the system to quickly locate a specific area, thereby improving the efficiency of positioning.

[0049] The anchor point position characteristic spectrum construction unit 13 constructs the corresponding anchor point position characteristic spectrum for each anchor point in the virtual grid. Specifically, the system can deploy a signal receiver at the anchor point position only during deployment testing, or can deploy a signal receiver at a fixed point for a long time to statically collect the characteristics of the signal sent by the pseudo-satellite at a certain rate, such as Figure 2 As shown, the signal characteristics may include the carrier phase, Doppler value and carrier-to-noise ratio value of the signal. By comprehensively calculating the above signal data, the anchor point position characteristic spectrum is formed. Specifically, when there are m pseudo-satellites in the indoor space, the anchor point position characteristic spectrum of any anchor point position can be expressed as:

[0050] ;

[0051] Specifically, in the formula of the above anchor point position characteristic spectrum, Carr diff represents the anchor point position characteristic spectrum, a carr represents the carrier of the pseudolite, a dopler represents the Doppler value of the pseudo-satellite, a cn0 Indicates the carrier-to-noise ratio of the pseudolite.

[0052] Furthermore, the corresponding parameters of the above anchor point position characteristic spectrum are obtained by WKNN weighted cumulative summation, and the corresponding parameters of the anchor point position characteristic spectrum are expressed by the following formula:

[0053] ;

[0054] In the formula, , , are the carrier phase, Doppler and carrier-to-noise ratio data sets collected at the anchor point positions, d i is the difference with the mean as the center point, k is the amount of data collected in 10 minutes, is the amount of random noise, is the weight coefficient.

[0055] The above-mentioned anchor point position characteristic spectrum can be used to deduce and calculate the signal characteristic information within the preset range of any anchor point position. For example, when the system provides positioning services for mobile terminals, the system selects an anchor point as the first anchor point, sets the search space within the preset range centered on the first anchor point position, and marks virtual points at preset intervals in the search space. In combination with the anchor point position characteristic library, the system can accurately deduce the signal characteristic information at the virtual points in the search space. Furthermore, the signal characteristic information of all virtual points in the above-mentioned search space can be recorded as the first signal characteristic parameter information, and the above-mentioned first signal characteristic parameter information can be used to construct the first signal characteristic parameter information library. The first signal characteristic parameter information library can be used to match the signal characteristic information of the signal received by the mobile terminal, find the point with the highest matching degree, and combine the position of the above-mentioned first anchor point to obtain the current position of the mobile terminal, thereby providing accurate positioning services to users.

[0056] According to the above description, the indoor positioning system applied to the GNSS micro base station, under the premise of not changing the satellite system, the pseudo-satellite sends a local simulated GNSS signal to the mobile terminal. At the same time, the system marks the anchor points of the indoor space, records the signal characteristics of any anchor point position, builds a virtual grid anchor point position feature library, and calculates and deduces the first signal characteristic parameter information at the virtual point in the search space based on the anchor point position characteristic spectrum of the anchor point position, thereby building a first signal characteristic parameter information library, which provides a data basis for the subsequent mobile terminal to receive the signal for matching and positioning, and lays the foundation for providing users with accurate positioning services in indoor environments.

[0057] Second, as Figure 3 As shown, the present application provides an indoor positioning system, which is applied to a mobile terminal and is characterized in that the system includes:

[0058] A signal acquisition unit 21 is used to receive signals broadcast by pseudo-satellites, where any pseudo-satellite broadcasts at least two signals with different frequencies;

[0059] The epoch position acquisition unit 22 is used to acquire the position of the first anchor point that is closest to the mobile terminal in the previous positioning cycle, and take the first anchor point as the optimal anchor point;

[0060] A search space construction unit 23, used to set the search space with the optimal anchor point as the center;

[0061] A characteristic parameter deduction unit 24 is used to deduce the first signal characteristic parameter information at all virtual points in the search space to construct a first signal characteristic parameter information library, and the search space is centered on the optimal anchor point;

[0062] The signal analyzing unit 25 is used to analyze the pseudo-satellite signal received by the signal acquiring unit 21 to obtain the second characteristic parameter information;

[0063] The positioning unit 26 is used to match the second characteristic parameter information with the first signal characteristic parameter information library, and in response to a successful match, obtain the position of the mobile terminal based on the position information of the optimal anchor point and the matching virtual point position in the search space.

[0064] As an optional implementation, the positioning unit 26 acquires the position using a particle swarm optimal position estimation algorithm according to the second characteristic parameter information and the first signal characteristic parameter information library.

[0065] Specifically, in the indoor positioning system of the embodiment of the present application, the signal acquisition unit 21 is responsible for receiving the signal broadcast by any pseudo-satellite, and any pseudo-satellite broadcasts at least two signals with different frequencies. Furthermore, there is a phase difference quantization change interval between the signals of different frequencies broadcast by the same pseudo-satellite. Based on the phase difference quantization change interval characteristics of the signals of different frequencies, the system performs regional segmentation processing on the indoor space according to the above characteristics; and there is also a characteristic of fixed phase difference at fixed points between the signals of the same frequency broadcast by different pseudo-satellites. The characteristic of fixed phase difference at fixed points of the same-frequency signals broadcast by different pseudo-satellites provides a basis for the system to construct an anchor point position characteristic spectrum.

[0066] The epoch position acquisition unit 22 calculates the distance between the mobile terminal and the anchor point in the search space in the previous positioning cycle based on the data in the previous positioning cycle, and takes the anchor point closest to the mobile terminal as the first anchor point, and the first anchor point is the optimal anchor point. The selection of the optimal anchor point helps the system to construct the search space in the next positioning cycle and improve the efficiency of system positioning.

[0067] The search space construction unit 23 sets a search space of a preset range size centered on the first anchor point based on the position information of the first anchor point. Specifically, the system reasonably constructs the search space based on the position information of the first anchor point and the preset search space range size. It should be noted that in practical applications, the search space can be a part of the indoor space or the entire indoor space. The setting of the search space ensures that the system performs subsequent positioning processing within a limited range, avoids the waste of the system's computing power, and improves the efficiency of the system in providing positioning services to users.

[0068] The characteristic parameter deduction unit 24 calculates and deduces the signal characteristic information of all virtual points in the search space based on the search space centered on the optimal anchor point and the signal characteristic information of the first anchor point, records the signal characteristic information of the virtual points as the first signal characteristic parameter information, and constructs a first signal characteristic parameter information library with the first signal characteristic parameter information of all virtual points in the search space. Specifically, the signal characteristic information may include one or more of carrier-to-noise ratio difference characteristics, Doppler difference characteristics, and carrier characteristics. The constructed first signal characteristic parameter information library provides comprehensive and accurate data support for the subsequent positioning matching of the system.

[0069] Based on the signal broadcast by the pseudo-satellite received in real time by the signal acquisition unit 21, the signal analysis unit 25 analyzes and processes the pseudo-satellite signal, extracts the signal characteristic information of the signal received by the mobile terminal, and records it as the second signal characteristic parameter information. The second signal characteristic parameter signal is an important basis for the subsequent system to realize the positioning of the mobile terminal.

[0070] When the signal analysis unit 25 completes the extraction of the second signal characteristic parameter information, Figure 4 As shown, the positioning unit 26 can perform similarity matching between the second signal characteristic parameter information and the first signal characteristic parameter library of the virtual point in the search space, select the virtual point with the highest similarity matching, and based on the position information of the optimal anchor point and the above-mentioned virtual point with the highest similarity matching, the positioning unit 26 can obtain the current position of the mobile terminal, thereby realizing that the system provides positioning services for the mobile terminal in the indoor space; in addition, the positioning unit 26 can also realize accurate acquisition of the mobile terminal position by comparing the second signal characteristic parameter information with the first signal characteristic parameter information library, and adopting the particle swarm optimal position estimation algorithm. This calculation method effectively reduces the complexity of calculation and positioning error while taking into account the diversity and complexity of the signal, thereby improving the accuracy of the indoor positioning system.

[0071] According to the above description, the indoor positioning system realizes efficient and accurate positioning of mobile terminals in indoor environments through the coordinated work of the above-mentioned units and the fine processing of indoor pseudo-satellite signals without changing the satellite signal system, providing an efficient and reliable solution for achieving accurate positioning of mobile terminals in indoor spaces.

[0072] As an optional implementation, the positioning frequency of the system is 5 Hz.

[0073] Specifically, in the indoor positioning system according to the embodiments of the present application, the positioning function of the system can be set to be updated at a frequency of 5 Hz, that is, the system can acquire and update the position information of the mobile terminal five times per second, ensuring the timeliness and accuracy of positioning, and helping the system to provide more accurate position services for the mobile terminal in situations that require real-time monitoring or in a dynamically changing indoor environment.

[0074] As an alternative implementation, the range of the search space is positively correlated with the positioning period of the system.

[0075] Specifically, in the indoor positioning system according to the embodiments of the present application, the preset range size of the search space can be flexibly adjusted according to actual applications to adapt to different application scenarios and requirements. It should be noted that there is a positive correlation between the range setting of the search space and the positioning period of the indoor positioning system. Specifically, the positioning period refers to the time required for the system to complete an update of the indoor space position. As the possible position changes in the indoor space occur, correspondingly, the system needs to expand the range of the search space to cope with potential position changes, and the positioning period of the system also extends accordingly, so as to ensure the accuracy of the system's positioning of the mobile terminal.

[0076] As an alternative implementation, as Figure 5 shown, the system further includes: a mode setting unit 27. The mode setting unit 27 is used to set a first mode. In the first mode, the horizontal movement speed of the mobile terminal is less than or equal to 2.8 m / s, and the horizontal dimension search radius of the search space is 0 m < R ≤ 0.56 m, and the vertical dimension search radius is 0.6 m ≤ H ≤ 1.6 m.

[0077] Specifically, in the indoor positioning system according to the embodiments of the present application, the mode setting unit 27 dynamically adjusts the positioning parameters according to the current motion state of the mobile terminal. For example, when the horizontal movement speed of the mobile terminal is less than or equal to 2.8 m / s, the mode setting unit 27 can recognize that the current mobile terminal is in a pedestrian movement state. Based on the recognition of the motion state of the mobile terminal, the mode setting unit 27 sets a first mode for the motion state of the mobile terminal. Specifically, in the first mode, the mode setting unit adjusts the dimensions of the search space. In the horizontal dimension, the horizontal dimension search radius of the search space is set to 0 m < R ≤ 0.56 m; in the vertical dimension, the vertical dimension search radius of the search space is set to 0.6 m ≤ H ≤ 1.6 m. The setting of the first mode by the mode setting unit 27 ensures that within the pedestrian speed range, the search and positioning of the mobile terminal position by the system are more refined, improving the positioning accuracy.

[0078] As an alternative implementation, the mode setting unit 27 is further configured to set a second mode. In the second mode, the horizontal movement speed of the mobile terminal is greater than 2.8 m / s and less than or equal to 10 m / s. And in the second mode, the horizontal dimension search radius of the search space is 0 m < R ≤ 2 m, and the vertical dimension search radius is 0.4 m ≤ H ≤ 0.6 m, or the vertical dimension search radius is 0.8 m ≤ H ≤ 1.2 m.

[0079] Specifically, in the indoor positioning system according to the embodiment of the present application, to meet the needs of different scenarios, for example, when providing positioning services for vehicles such as private cars and urban buses, the mode setting unit 27 can also set the second mode according to the current motion state of the mobile terminal. For example, when the horizontal movement speed of the mobile terminal is greater than 2.8 m / s and less than or equal to 10 m / s, the mode setting unit 27 can identify that the current mobile terminal is in a vehicle motion state. Based on the recognition of the motion state of the mobile terminal, the mode setting unit 27 sets the second mode for the motion state of the mobile terminal. Specifically, in the second mode, the mode setting unit 27 adjusts the dimensions of the search space. In the horizontal dimension, the horizontal dimension search radius of the search space is 0 m < R ≤ 2 m; in the vertical dimension, according to the different vehicle heights, the vertical dimension search radius of the search space can be 0.4 m ≤ H ≤ 0.6 m, or the vertical dimension search radius can be 0.8 m ≤ H ≤ 1.2 m. The setting of the second mode by the mode setting unit 27 improves the flexibility of the system to provide positioning services for the mobile terminal when the mobile terminal is in a vehicle motion state.

[0080] According to the above description, the mode setting unit 27 improves the accuracy of the positioning system by intelligently judging the motion state of the mobile terminal and adjusting the search space parameters accordingly, meets the requirement of providing location positioning services for users in different scenarios, and avoids the waste of system computing power by flexibly adjusting the range of the search space of the positioning system, thereby improving the efficiency of the system to provide positioning services for users.

[0081] In summary, an indoor positioning system applied to a mobile terminal, without changing the satellite signal system, obtains the signal feature information of the received signal of the mobile terminal by analyzing the locally simulated GNSS signal sent by the pseudolite, matches the signal feature information of the received signal of the mobile terminal with the signal feature information at all virtual points in the search space, obtains the point in the search space with the highest similarity to the signal feature information of the received signal of the mobile terminal, combines the point with the highest similarity of the above signal feature information and the center point (i.e., the first anchor point) of the search space, obtains the current position information of the mobile terminal, realizes providing high-precision positioning services for users in an indoor environment, and improves the accuracy and reliability of the positioning through fine signal processing technology.

[0082] It will be appreciated that the word "exemplary" as used herein means "serving as an example, instance, or illustration". Any embodiment described as "exemplary" is not necessarily preferred or superior to other embodiments and / or does not exclude the combination of features of other embodiments. It will be appreciated that certain features of the present application described in the context of separate embodiments for the sake of clarity may also be provided in a single embodiment by combination. Conversely, various features of the present application described in the context of a single embodiment for the sake of clarity may also be provided individually or in any suitable combination or as any other described embodiment of the present application.

[0083] The above disclosure is only the preferred embodiment of the present application, but it is not intended to limit the scope of rights of the present application. A person of ordinary skill in the art can understand that without departing from the spirit and scope of the present application and the appended claims, changes, modifications, substitutions, combinations, and simplifications should all be equivalent replacement methods and still fall within the scope of the invention.

Claims

1. An indoor positioning system, applied to a GNSS micro base station, characterized in that: The system comprises: A plurality of pseudo-satellites, any of which broadcasts at least two signals with different frequencies; A virtual grid construction unit is used to segment the garage space into virtual grids, set anchor points for each segment of the virtual grid, and record the position information of the anchor points to establish a virtual grid anchor point position feature library; An anchor point position characteristic spectrum construction unit, used for constructing an anchor point position characteristic spectrum corresponding to any anchor point; Among them, the anchor point position characteristic spectrum is used to deduce the first signal characteristic parameter information at all virtual points in the search space to construct a first signal characteristic parameter information library. The search space is centered on the first anchor point, and in response to the second characteristic parameter information of the signal received by the mobile terminal matching the first signal characteristic parameter information, the position of the mobile terminal is obtained based on the position information of the first anchor point and the matching virtual points in the search space.

2. The indoor positioning system according to claim 1, characterized in that: The anchor point position characteristic spectrum is expressed by the following formula: ； In the formula, , , represents the carrier, Doppler, and carrier-to-noise ratio values ​​of the mth pseudo-satellite signal received at the anchor point.

3. The indoor positioning system according to claim 2, characterized in that: The corresponding parameters of the anchor point position characteristic spectrum are obtained by WKNN weighted cumulative summation, and the corresponding parameters of the anchor point position characteristic spectrum are expressed by the following formula: ； In the formula, , , are the carrier phase, Doppler and carrier-to-noise ratio data sets collected at the anchor point positions, d i is the difference with the mean as the center point, k is the amount of data collected in 10 minutes, is the amount of random noise, is the weight coefficient.

4. The indoor positioning system according to claim 1, characterized in that: The anchor point settings include at least the following locations: garage entrance, garage exit, entrance corner, lane intersection, and lane ten-meter dividing point.

5. An indoor positioning system, applied to a mobile terminal, characterized in that: The system comprises: A signal acquisition unit, configured to receive signals broadcast by pseudo-satellites, wherein any of the pseudo-satellites broadcasts at least two satellite signals with different frequencies; an epoch position acquisition unit, configured to acquire the position of a first anchor point that is closest to the mobile terminal during the last positioning cycle, and take the first anchor point as the optimal anchor point; A search space construction unit, used to set the search space with the optimal anchor point as the center; A characteristic parameter deduction unit, used to deduce the first signal characteristic parameter information at all virtual points in a search space to construct a first signal characteristic parameter information library, wherein the search space is centered on the optimal anchor point; A signal analysis unit, used for analyzing the pseudo-satellite signal received by the signal acquisition unit to obtain second characteristic parameter information; A positioning unit is used to match the second characteristic parameter information with the first signal characteristic parameter information library, and in response to a successful match, obtain the position of the mobile terminal based on the position information of the optimal anchor point and the matching virtual point position of the search space.

6. The system according to claim 5, characterized in that The positioning unit completes position acquisition by using a particle swarm optimal position estimation algorithm according to the second characteristic parameter information and the first signal characteristic parameter information library.

7. The system according to claim 5, characterized in that The range of the search space is positively correlated with the positioning period of the system.

8. The system according to claim 7, characterized in that The positioning frequency of the system is 5 Hz.

9. The system according to claim 7, characterized in that The system further comprises: A mode setting unit, which is used to set a first mode. In the first mode, the horizontal moving speed of the mobile terminal is less than or equal to 2.8 m / s, and the horizontal dimension search radius of the search space is 0 m < R ≤ 0.56 m, and the vertical dimension search radius is 0.6 m ≤ H ≤ 1.6 m.

10. The system according to claim 9, wherein the mode setting unit is further used to set a second mode. In the second mode, the horizontal moving speed of the mobile terminal is greater than 2.8 m / s and less than or equal to 10 m / s, and in the second mode, the horizontal dimension search radius of the search space is 0 m < R ≤ 2 m, and the vertical dimension search radius is 0.4 m ≤ H ≤ 0.6 m, or the vertical dimension search radius is 0.8 m ≤ H ≤ 1.2 m.

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